PM: domains: Move genpd and its governor to the pmdomain subsystem
authorUlf Hansson <ulf.hansson@linaro.org>
Wed, 13 Dec 2023 11:33:05 +0000 (12:33 +0100)
committerUlf Hansson <ulf.hansson@linaro.org>
Mon, 18 Dec 2023 11:49:48 +0000 (12:49 +0100)
It seems reasonable to collect the core parts for the generic PM domain,
along with its corresponding provider drivers. Therefore let's move the
files from drivers/base/power/ to drivers/pmdomain/ and while at it, let's
also rename the files accordingly.

Moreover, let's also update MAINTAINERS to reflect the update.

Cc: Kevin Hilman <khilman@kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20231213113305.29098-1-ulf.hansson@linaro.org
MAINTAINERS
drivers/base/power/Makefile
drivers/base/power/domain.c [deleted file]
drivers/base/power/domain_governor.c [deleted file]
drivers/pmdomain/Makefile
drivers/pmdomain/core.c [new file with mode: 0644]
drivers/pmdomain/governor.c [new file with mode: 0644]

index ea790149af795155003eaacca87289e05d55454b..ab4b0aed34f933a0da8a0310e936bef3d17cb208 100644 (file)
@@ -8878,21 +8878,13 @@ F:      Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.yaml
 F:     drivers/i2c/muxes/i2c-demux-pinctrl.c
 
 GENERIC PM DOMAINS
-M:     "Rafael J. Wysocki" <rafael@kernel.org>
-M:     Kevin Hilman <khilman@kernel.org>
 M:     Ulf Hansson <ulf.hansson@linaro.org>
 L:     linux-pm@vger.kernel.org
 S:     Supported
 F:     Documentation/devicetree/bindings/power/power?domain*
-F:     drivers/base/power/domain*.c
-F:     include/linux/pm_domain.h
-
-GENERIC PM DOMAIN PROVIDERS
-M:     Ulf Hansson <ulf.hansson@linaro.org>
-L:     linux-pm@vger.kernel.org
-S:     Supported
 T:     git git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/linux-pm.git
 F:     drivers/pmdomain/
+F:     include/linux/pm_domain.h
 
 GENERIC RADIX TREE
 M:     Kent Overstreet <kent.overstreet@linux.dev>
index 8fdd0073eeebce6bdf24a113c6ddd00d61a4b8b9..01f11629d241cd3f7b75843e154474eb160a8bd1 100644 (file)
@@ -2,7 +2,6 @@
 obj-$(CONFIG_PM)       += sysfs.o generic_ops.o common.o qos.o runtime.o wakeirq.o
 obj-$(CONFIG_PM_SLEEP) += main.o wakeup.o wakeup_stats.o
 obj-$(CONFIG_PM_TRACE_RTC)     += trace.o
-obj-$(CONFIG_PM_GENERIC_DOMAINS)       +=  domain.o domain_governor.o
 obj-$(CONFIG_HAVE_CLK) += clock_ops.o
 obj-$(CONFIG_PM_QOS_KUNIT_TEST) += qos-test.o
 
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
deleted file mode 100644 (file)
index 9ee1bf2..0000000
+++ /dev/null
@@ -1,3399 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * drivers/base/power/domain.c - Common code related to device power domains.
- *
- * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
- */
-#define pr_fmt(fmt) "PM: " fmt
-
-#include <linux/delay.h>
-#include <linux/kernel.h>
-#include <linux/io.h>
-#include <linux/platform_device.h>
-#include <linux/pm_opp.h>
-#include <linux/pm_runtime.h>
-#include <linux/pm_domain.h>
-#include <linux/pm_qos.h>
-#include <linux/pm_clock.h>
-#include <linux/slab.h>
-#include <linux/err.h>
-#include <linux/sched.h>
-#include <linux/suspend.h>
-#include <linux/export.h>
-#include <linux/cpu.h>
-#include <linux/debugfs.h>
-
-#define GENPD_RETRY_MAX_MS     250             /* Approximate */
-
-#define GENPD_DEV_CALLBACK(genpd, type, callback, dev)         \
-({                                                             \
-       type (*__routine)(struct device *__d);                  \
-       type __ret = (type)0;                                   \
-                                                               \
-       __routine = genpd->dev_ops.callback;                    \
-       if (__routine) {                                        \
-               __ret = __routine(dev);                         \
-       }                                                       \
-       __ret;                                                  \
-})
-
-static LIST_HEAD(gpd_list);
-static DEFINE_MUTEX(gpd_list_lock);
-
-struct genpd_lock_ops {
-       void (*lock)(struct generic_pm_domain *genpd);
-       void (*lock_nested)(struct generic_pm_domain *genpd, int depth);
-       int (*lock_interruptible)(struct generic_pm_domain *genpd);
-       void (*unlock)(struct generic_pm_domain *genpd);
-};
-
-static void genpd_lock_mtx(struct generic_pm_domain *genpd)
-{
-       mutex_lock(&genpd->mlock);
-}
-
-static void genpd_lock_nested_mtx(struct generic_pm_domain *genpd,
-                                       int depth)
-{
-       mutex_lock_nested(&genpd->mlock, depth);
-}
-
-static int genpd_lock_interruptible_mtx(struct generic_pm_domain *genpd)
-{
-       return mutex_lock_interruptible(&genpd->mlock);
-}
-
-static void genpd_unlock_mtx(struct generic_pm_domain *genpd)
-{
-       return mutex_unlock(&genpd->mlock);
-}
-
-static const struct genpd_lock_ops genpd_mtx_ops = {
-       .lock = genpd_lock_mtx,
-       .lock_nested = genpd_lock_nested_mtx,
-       .lock_interruptible = genpd_lock_interruptible_mtx,
-       .unlock = genpd_unlock_mtx,
-};
-
-static void genpd_lock_spin(struct generic_pm_domain *genpd)
-       __acquires(&genpd->slock)
-{
-       unsigned long flags;
-
-       spin_lock_irqsave(&genpd->slock, flags);
-       genpd->lock_flags = flags;
-}
-
-static void genpd_lock_nested_spin(struct generic_pm_domain *genpd,
-                                       int depth)
-       __acquires(&genpd->slock)
-{
-       unsigned long flags;
-
-       spin_lock_irqsave_nested(&genpd->slock, flags, depth);
-       genpd->lock_flags = flags;
-}
-
-static int genpd_lock_interruptible_spin(struct generic_pm_domain *genpd)
-       __acquires(&genpd->slock)
-{
-       unsigned long flags;
-
-       spin_lock_irqsave(&genpd->slock, flags);
-       genpd->lock_flags = flags;
-       return 0;
-}
-
-static void genpd_unlock_spin(struct generic_pm_domain *genpd)
-       __releases(&genpd->slock)
-{
-       spin_unlock_irqrestore(&genpd->slock, genpd->lock_flags);
-}
-
-static const struct genpd_lock_ops genpd_spin_ops = {
-       .lock = genpd_lock_spin,
-       .lock_nested = genpd_lock_nested_spin,
-       .lock_interruptible = genpd_lock_interruptible_spin,
-       .unlock = genpd_unlock_spin,
-};
-
-#define genpd_lock(p)                  p->lock_ops->lock(p)
-#define genpd_lock_nested(p, d)                p->lock_ops->lock_nested(p, d)
-#define genpd_lock_interruptible(p)    p->lock_ops->lock_interruptible(p)
-#define genpd_unlock(p)                        p->lock_ops->unlock(p)
-
-#define genpd_status_on(genpd)         (genpd->status == GENPD_STATE_ON)
-#define genpd_is_irq_safe(genpd)       (genpd->flags & GENPD_FLAG_IRQ_SAFE)
-#define genpd_is_always_on(genpd)      (genpd->flags & GENPD_FLAG_ALWAYS_ON)
-#define genpd_is_active_wakeup(genpd)  (genpd->flags & GENPD_FLAG_ACTIVE_WAKEUP)
-#define genpd_is_cpu_domain(genpd)     (genpd->flags & GENPD_FLAG_CPU_DOMAIN)
-#define genpd_is_rpm_always_on(genpd)  (genpd->flags & GENPD_FLAG_RPM_ALWAYS_ON)
-#define genpd_is_opp_table_fw(genpd)   (genpd->flags & GENPD_FLAG_OPP_TABLE_FW)
-
-static inline bool irq_safe_dev_in_sleep_domain(struct device *dev,
-               const struct generic_pm_domain *genpd)
-{
-       bool ret;
-
-       ret = pm_runtime_is_irq_safe(dev) && !genpd_is_irq_safe(genpd);
-
-       /*
-        * Warn once if an IRQ safe device is attached to a domain, which
-        * callbacks are allowed to sleep. This indicates a suboptimal
-        * configuration for PM, but it doesn't matter for an always on domain.
-        */
-       if (genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd))
-               return ret;
-
-       if (ret)
-               dev_warn_once(dev, "PM domain %s will not be powered off\n",
-                               genpd->name);
-
-       return ret;
-}
-
-static int genpd_runtime_suspend(struct device *dev);
-
-/*
- * Get the generic PM domain for a particular struct device.
- * This validates the struct device pointer, the PM domain pointer,
- * and checks that the PM domain pointer is a real generic PM domain.
- * Any failure results in NULL being returned.
- */
-static struct generic_pm_domain *dev_to_genpd_safe(struct device *dev)
-{
-       if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain))
-               return NULL;
-
-       /* A genpd's always have its ->runtime_suspend() callback assigned. */
-       if (dev->pm_domain->ops.runtime_suspend == genpd_runtime_suspend)
-               return pd_to_genpd(dev->pm_domain);
-
-       return NULL;
-}
-
-/*
- * This should only be used where we are certain that the pm_domain
- * attached to the device is a genpd domain.
- */
-static struct generic_pm_domain *dev_to_genpd(struct device *dev)
-{
-       if (IS_ERR_OR_NULL(dev->pm_domain))
-               return ERR_PTR(-EINVAL);
-
-       return pd_to_genpd(dev->pm_domain);
-}
-
-static int genpd_stop_dev(const struct generic_pm_domain *genpd,
-                         struct device *dev)
-{
-       return GENPD_DEV_CALLBACK(genpd, int, stop, dev);
-}
-
-static int genpd_start_dev(const struct generic_pm_domain *genpd,
-                          struct device *dev)
-{
-       return GENPD_DEV_CALLBACK(genpd, int, start, dev);
-}
-
-static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
-{
-       bool ret = false;
-
-       if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
-               ret = !!atomic_dec_and_test(&genpd->sd_count);
-
-       return ret;
-}
-
-static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
-{
-       atomic_inc(&genpd->sd_count);
-       smp_mb__after_atomic();
-}
-
-#ifdef CONFIG_DEBUG_FS
-static struct dentry *genpd_debugfs_dir;
-
-static void genpd_debug_add(struct generic_pm_domain *genpd);
-
-static void genpd_debug_remove(struct generic_pm_domain *genpd)
-{
-       if (!genpd_debugfs_dir)
-               return;
-
-       debugfs_lookup_and_remove(genpd->name, genpd_debugfs_dir);
-}
-
-static void genpd_update_accounting(struct generic_pm_domain *genpd)
-{
-       u64 delta, now;
-
-       now = ktime_get_mono_fast_ns();
-       if (now <= genpd->accounting_time)
-               return;
-
-       delta = now - genpd->accounting_time;
-
-       /*
-        * If genpd->status is active, it means we are just
-        * out of off and so update the idle time and vice
-        * versa.
-        */
-       if (genpd->status == GENPD_STATE_ON)
-               genpd->states[genpd->state_idx].idle_time += delta;
-       else
-               genpd->on_time += delta;
-
-       genpd->accounting_time = now;
-}
-#else
-static inline void genpd_debug_add(struct generic_pm_domain *genpd) {}
-static inline void genpd_debug_remove(struct generic_pm_domain *genpd) {}
-static inline void genpd_update_accounting(struct generic_pm_domain *genpd) {}
-#endif
-
-static int _genpd_reeval_performance_state(struct generic_pm_domain *genpd,
-                                          unsigned int state)
-{
-       struct generic_pm_domain_data *pd_data;
-       struct pm_domain_data *pdd;
-       struct gpd_link *link;
-
-       /* New requested state is same as Max requested state */
-       if (state == genpd->performance_state)
-               return state;
-
-       /* New requested state is higher than Max requested state */
-       if (state > genpd->performance_state)
-               return state;
-
-       /* Traverse all devices within the domain */
-       list_for_each_entry(pdd, &genpd->dev_list, list_node) {
-               pd_data = to_gpd_data(pdd);
-
-               if (pd_data->performance_state > state)
-                       state = pd_data->performance_state;
-       }
-
-       /*
-        * Traverse all sub-domains within the domain. This can be
-        * done without any additional locking as the link->performance_state
-        * field is protected by the parent genpd->lock, which is already taken.
-        *
-        * Also note that link->performance_state (subdomain's performance state
-        * requirement to parent domain) is different from
-        * link->child->performance_state (current performance state requirement
-        * of the devices/sub-domains of the subdomain) and so can have a
-        * different value.
-        *
-        * Note that we also take vote from powered-off sub-domains into account
-        * as the same is done for devices right now.
-        */
-       list_for_each_entry(link, &genpd->parent_links, parent_node) {
-               if (link->performance_state > state)
-                       state = link->performance_state;
-       }
-
-       return state;
-}
-
-static int genpd_xlate_performance_state(struct generic_pm_domain *genpd,
-                                        struct generic_pm_domain *parent,
-                                        unsigned int pstate)
-{
-       if (!parent->set_performance_state)
-               return pstate;
-
-       return dev_pm_opp_xlate_performance_state(genpd->opp_table,
-                                                 parent->opp_table,
-                                                 pstate);
-}
-
-static int _genpd_set_performance_state(struct generic_pm_domain *genpd,
-                                       unsigned int state, int depth)
-{
-       struct generic_pm_domain *parent;
-       struct gpd_link *link;
-       int parent_state, ret;
-
-       if (state == genpd->performance_state)
-               return 0;
-
-       /* Propagate to parents of genpd */
-       list_for_each_entry(link, &genpd->child_links, child_node) {
-               parent = link->parent;
-
-               /* Find parent's performance state */
-               ret = genpd_xlate_performance_state(genpd, parent, state);
-               if (unlikely(ret < 0))
-                       goto err;
-
-               parent_state = ret;
-
-               genpd_lock_nested(parent, depth + 1);
-
-               link->prev_performance_state = link->performance_state;
-               link->performance_state = parent_state;
-               parent_state = _genpd_reeval_performance_state(parent,
-                                               parent_state);
-               ret = _genpd_set_performance_state(parent, parent_state, depth + 1);
-               if (ret)
-                       link->performance_state = link->prev_performance_state;
-
-               genpd_unlock(parent);
-
-               if (ret)
-                       goto err;
-       }
-
-       if (genpd->set_performance_state) {
-               ret = genpd->set_performance_state(genpd, state);
-               if (ret)
-                       goto err;
-       }
-
-       genpd->performance_state = state;
-       return 0;
-
-err:
-       /* Encountered an error, lets rollback */
-       list_for_each_entry_continue_reverse(link, &genpd->child_links,
-                                            child_node) {
-               parent = link->parent;
-
-               genpd_lock_nested(parent, depth + 1);
-
-               parent_state = link->prev_performance_state;
-               link->performance_state = parent_state;
-
-               parent_state = _genpd_reeval_performance_state(parent,
-                                               parent_state);
-               if (_genpd_set_performance_state(parent, parent_state, depth + 1)) {
-                       pr_err("%s: Failed to roll back to %d performance state\n",
-                              parent->name, parent_state);
-               }
-
-               genpd_unlock(parent);
-       }
-
-       return ret;
-}
-
-static int genpd_set_performance_state(struct device *dev, unsigned int state)
-{
-       struct generic_pm_domain *genpd = dev_to_genpd(dev);
-       struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
-       unsigned int prev_state;
-       int ret;
-
-       prev_state = gpd_data->performance_state;
-       if (prev_state == state)
-               return 0;
-
-       gpd_data->performance_state = state;
-       state = _genpd_reeval_performance_state(genpd, state);
-
-       ret = _genpd_set_performance_state(genpd, state, 0);
-       if (ret)
-               gpd_data->performance_state = prev_state;
-
-       return ret;
-}
-
-static int genpd_drop_performance_state(struct device *dev)
-{
-       unsigned int prev_state = dev_gpd_data(dev)->performance_state;
-
-       if (!genpd_set_performance_state(dev, 0))
-               return prev_state;
-
-       return 0;
-}
-
-static void genpd_restore_performance_state(struct device *dev,
-                                           unsigned int state)
-{
-       if (state)
-               genpd_set_performance_state(dev, state);
-}
-
-static int genpd_dev_pm_set_performance_state(struct device *dev,
-                                             unsigned int state)
-{
-       struct generic_pm_domain *genpd = dev_to_genpd(dev);
-       int ret = 0;
-
-       genpd_lock(genpd);
-       if (pm_runtime_suspended(dev)) {
-               dev_gpd_data(dev)->rpm_pstate = state;
-       } else {
-               ret = genpd_set_performance_state(dev, state);
-               if (!ret)
-                       dev_gpd_data(dev)->rpm_pstate = 0;
-       }
-       genpd_unlock(genpd);
-
-       return ret;
-}
-
-/**
- * dev_pm_genpd_set_performance_state- Set performance state of device's power
- * domain.
- *
- * @dev: Device for which the performance-state needs to be set.
- * @state: Target performance state of the device. This can be set as 0 when the
- *        device doesn't have any performance state constraints left (And so
- *        the device wouldn't participate anymore to find the target
- *        performance state of the genpd).
- *
- * It is assumed that the users guarantee that the genpd wouldn't be detached
- * while this routine is getting called.
- *
- * Returns 0 on success and negative error values on failures.
- */
-int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state)
-{
-       struct generic_pm_domain *genpd;
-
-       genpd = dev_to_genpd_safe(dev);
-       if (!genpd)
-               return -ENODEV;
-
-       if (WARN_ON(!dev->power.subsys_data ||
-                    !dev->power.subsys_data->domain_data))
-               return -EINVAL;
-
-       return genpd_dev_pm_set_performance_state(dev, state);
-}
-EXPORT_SYMBOL_GPL(dev_pm_genpd_set_performance_state);
-
-/**
- * dev_pm_genpd_set_next_wakeup - Notify PM framework of an impending wakeup.
- *
- * @dev: Device to handle
- * @next: impending interrupt/wakeup for the device
- *
- *
- * Allow devices to inform of the next wakeup. It's assumed that the users
- * guarantee that the genpd wouldn't be detached while this routine is getting
- * called. Additionally, it's also assumed that @dev isn't runtime suspended
- * (RPM_SUSPENDED)."
- * Although devices are expected to update the next_wakeup after the end of
- * their usecase as well, it is possible the devices themselves may not know
- * about that, so stale @next will be ignored when powering off the domain.
- */
-void dev_pm_genpd_set_next_wakeup(struct device *dev, ktime_t next)
-{
-       struct generic_pm_domain *genpd;
-       struct gpd_timing_data *td;
-
-       genpd = dev_to_genpd_safe(dev);
-       if (!genpd)
-               return;
-
-       td = to_gpd_data(dev->power.subsys_data->domain_data)->td;
-       if (td)
-               td->next_wakeup = next;
-}
-EXPORT_SYMBOL_GPL(dev_pm_genpd_set_next_wakeup);
-
-/**
- * dev_pm_genpd_get_next_hrtimer - Return the next_hrtimer for the genpd
- * @dev: A device that is attached to the genpd.
- *
- * This routine should typically be called for a device, at the point of when a
- * GENPD_NOTIFY_PRE_OFF notification has been sent for it.
- *
- * Returns the aggregated value of the genpd's next hrtimer or KTIME_MAX if no
- * valid value have been set.
- */
-ktime_t dev_pm_genpd_get_next_hrtimer(struct device *dev)
-{
-       struct generic_pm_domain *genpd;
-
-       genpd = dev_to_genpd_safe(dev);
-       if (!genpd)
-               return KTIME_MAX;
-
-       if (genpd->gd)
-               return genpd->gd->next_hrtimer;
-
-       return KTIME_MAX;
-}
-EXPORT_SYMBOL_GPL(dev_pm_genpd_get_next_hrtimer);
-
-/*
- * dev_pm_genpd_synced_poweroff - Next power off should be synchronous
- *
- * @dev: A device that is attached to the genpd.
- *
- * Allows a consumer of the genpd to notify the provider that the next power off
- * should be synchronous.
- *
- * It is assumed that the users guarantee that the genpd wouldn't be detached
- * while this routine is getting called.
- */
-void dev_pm_genpd_synced_poweroff(struct device *dev)
-{
-       struct generic_pm_domain *genpd;
-
-       genpd = dev_to_genpd_safe(dev);
-       if (!genpd)
-               return;
-
-       genpd_lock(genpd);
-       genpd->synced_poweroff = true;
-       genpd_unlock(genpd);
-}
-EXPORT_SYMBOL_GPL(dev_pm_genpd_synced_poweroff);
-
-static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed)
-{
-       unsigned int state_idx = genpd->state_idx;
-       ktime_t time_start;
-       s64 elapsed_ns;
-       int ret;
-
-       /* Notify consumers that we are about to power on. */
-       ret = raw_notifier_call_chain_robust(&genpd->power_notifiers,
-                                            GENPD_NOTIFY_PRE_ON,
-                                            GENPD_NOTIFY_OFF, NULL);
-       ret = notifier_to_errno(ret);
-       if (ret)
-               return ret;
-
-       if (!genpd->power_on)
-               goto out;
-
-       timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
-       if (!timed) {
-               ret = genpd->power_on(genpd);
-               if (ret)
-                       goto err;
-
-               goto out;
-       }
-
-       time_start = ktime_get();
-       ret = genpd->power_on(genpd);
-       if (ret)
-               goto err;
-
-       elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
-       if (elapsed_ns <= genpd->states[state_idx].power_on_latency_ns)
-               goto out;
-
-       genpd->states[state_idx].power_on_latency_ns = elapsed_ns;
-       genpd->gd->max_off_time_changed = true;
-       pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
-                genpd->name, "on", elapsed_ns);
-
-out:
-       raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL);
-       genpd->synced_poweroff = false;
-       return 0;
-err:
-       raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF,
-                               NULL);
-       return ret;
-}
-
-static int _genpd_power_off(struct generic_pm_domain *genpd, bool timed)
-{
-       unsigned int state_idx = genpd->state_idx;
-       ktime_t time_start;
-       s64 elapsed_ns;
-       int ret;
-
-       /* Notify consumers that we are about to power off. */
-       ret = raw_notifier_call_chain_robust(&genpd->power_notifiers,
-                                            GENPD_NOTIFY_PRE_OFF,
-                                            GENPD_NOTIFY_ON, NULL);
-       ret = notifier_to_errno(ret);
-       if (ret)
-               return ret;
-
-       if (!genpd->power_off)
-               goto out;
-
-       timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
-       if (!timed) {
-               ret = genpd->power_off(genpd);
-               if (ret)
-                       goto busy;
-
-               goto out;
-       }
-
-       time_start = ktime_get();
-       ret = genpd->power_off(genpd);
-       if (ret)
-               goto busy;
-
-       elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
-       if (elapsed_ns <= genpd->states[state_idx].power_off_latency_ns)
-               goto out;
-
-       genpd->states[state_idx].power_off_latency_ns = elapsed_ns;
-       genpd->gd->max_off_time_changed = true;
-       pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
-                genpd->name, "off", elapsed_ns);
-
-out:
-       raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF,
-                               NULL);
-       return 0;
-busy:
-       raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL);
-       return ret;
-}
-
-/**
- * genpd_queue_power_off_work - Queue up the execution of genpd_power_off().
- * @genpd: PM domain to power off.
- *
- * Queue up the execution of genpd_power_off() unless it's already been done
- * before.
- */
-static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
-{
-       queue_work(pm_wq, &genpd->power_off_work);
-}
-
-/**
- * genpd_power_off - Remove power from a given PM domain.
- * @genpd: PM domain to power down.
- * @one_dev_on: If invoked from genpd's ->runtime_suspend|resume() callback, the
- * RPM status of the releated device is in an intermediate state, not yet turned
- * into RPM_SUSPENDED. This means genpd_power_off() must allow one device to not
- * be RPM_SUSPENDED, while it tries to power off the PM domain.
- * @depth: nesting count for lockdep.
- *
- * If all of the @genpd's devices have been suspended and all of its subdomains
- * have been powered down, remove power from @genpd.
- */
-static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on,
-                          unsigned int depth)
-{
-       struct pm_domain_data *pdd;
-       struct gpd_link *link;
-       unsigned int not_suspended = 0;
-       int ret;
-
-       /*
-        * Do not try to power off the domain in the following situations:
-        * (1) The domain is already in the "power off" state.
-        * (2) System suspend is in progress.
-        */
-       if (!genpd_status_on(genpd) || genpd->prepared_count > 0)
-               return 0;
-
-       /*
-        * Abort power off for the PM domain in the following situations:
-        * (1) The domain is configured as always on.
-        * (2) When the domain has a subdomain being powered on.
-        */
-       if (genpd_is_always_on(genpd) ||
-                       genpd_is_rpm_always_on(genpd) ||
-                       atomic_read(&genpd->sd_count) > 0)
-               return -EBUSY;
-
-       /*
-        * The children must be in their deepest (powered-off) states to allow
-        * the parent to be powered off. Note that, there's no need for
-        * additional locking, as powering on a child, requires the parent's
-        * lock to be acquired first.
-        */
-       list_for_each_entry(link, &genpd->parent_links, parent_node) {
-               struct generic_pm_domain *child = link->child;
-               if (child->state_idx < child->state_count - 1)
-                       return -EBUSY;
-       }
-
-       list_for_each_entry(pdd, &genpd->dev_list, list_node) {
-               /*
-                * Do not allow PM domain to be powered off, when an IRQ safe
-                * device is part of a non-IRQ safe domain.
-                */
-               if (!pm_runtime_suspended(pdd->dev) ||
-                       irq_safe_dev_in_sleep_domain(pdd->dev, genpd))
-                       not_suspended++;
-       }
-
-       if (not_suspended > 1 || (not_suspended == 1 && !one_dev_on))
-               return -EBUSY;
-
-       if (genpd->gov && genpd->gov->power_down_ok) {
-               if (!genpd->gov->power_down_ok(&genpd->domain))
-                       return -EAGAIN;
-       }
-
-       /* Default to shallowest state. */
-       if (!genpd->gov)
-               genpd->state_idx = 0;
-
-       /* Don't power off, if a child domain is waiting to power on. */
-       if (atomic_read(&genpd->sd_count) > 0)
-               return -EBUSY;
-
-       ret = _genpd_power_off(genpd, true);
-       if (ret) {
-               genpd->states[genpd->state_idx].rejected++;
-               return ret;
-       }
-
-       genpd->status = GENPD_STATE_OFF;
-       genpd_update_accounting(genpd);
-       genpd->states[genpd->state_idx].usage++;
-
-       list_for_each_entry(link, &genpd->child_links, child_node) {
-               genpd_sd_counter_dec(link->parent);
-               genpd_lock_nested(link->parent, depth + 1);
-               genpd_power_off(link->parent, false, depth + 1);
-               genpd_unlock(link->parent);
-       }
-
-       return 0;
-}
-
-/**
- * genpd_power_on - Restore power to a given PM domain and its parents.
- * @genpd: PM domain to power up.
- * @depth: nesting count for lockdep.
- *
- * Restore power to @genpd and all of its parents so that it is possible to
- * resume a device belonging to it.
- */
-static int genpd_power_on(struct generic_pm_domain *genpd, unsigned int depth)
-{
-       struct gpd_link *link;
-       int ret = 0;
-
-       if (genpd_status_on(genpd))
-               return 0;
-
-       /*
-        * The list is guaranteed not to change while the loop below is being
-        * executed, unless one of the parents' .power_on() callbacks fiddles
-        * with it.
-        */
-       list_for_each_entry(link, &genpd->child_links, child_node) {
-               struct generic_pm_domain *parent = link->parent;
-
-               genpd_sd_counter_inc(parent);
-
-               genpd_lock_nested(parent, depth + 1);
-               ret = genpd_power_on(parent, depth + 1);
-               genpd_unlock(parent);
-
-               if (ret) {
-                       genpd_sd_counter_dec(parent);
-                       goto err;
-               }
-       }
-
-       ret = _genpd_power_on(genpd, true);
-       if (ret)
-               goto err;
-
-       genpd->status = GENPD_STATE_ON;
-       genpd_update_accounting(genpd);
-
-       return 0;
-
- err:
-       list_for_each_entry_continue_reverse(link,
-                                       &genpd->child_links,
-                                       child_node) {
-               genpd_sd_counter_dec(link->parent);
-               genpd_lock_nested(link->parent, depth + 1);
-               genpd_power_off(link->parent, false, depth + 1);
-               genpd_unlock(link->parent);
-       }
-
-       return ret;
-}
-
-static int genpd_dev_pm_start(struct device *dev)
-{
-       struct generic_pm_domain *genpd = dev_to_genpd(dev);
-
-       return genpd_start_dev(genpd, dev);
-}
-
-static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
-                                    unsigned long val, void *ptr)
-{
-       struct generic_pm_domain_data *gpd_data;
-       struct device *dev;
-
-       gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
-       dev = gpd_data->base.dev;
-
-       for (;;) {
-               struct generic_pm_domain *genpd = ERR_PTR(-ENODATA);
-               struct pm_domain_data *pdd;
-               struct gpd_timing_data *td;
-
-               spin_lock_irq(&dev->power.lock);
-
-               pdd = dev->power.subsys_data ?
-                               dev->power.subsys_data->domain_data : NULL;
-               if (pdd) {
-                       td = to_gpd_data(pdd)->td;
-                       if (td) {
-                               td->constraint_changed = true;
-                               genpd = dev_to_genpd(dev);
-                       }
-               }
-
-               spin_unlock_irq(&dev->power.lock);
-
-               if (!IS_ERR(genpd)) {
-                       genpd_lock(genpd);
-                       genpd->gd->max_off_time_changed = true;
-                       genpd_unlock(genpd);
-               }
-
-               dev = dev->parent;
-               if (!dev || dev->power.ignore_children)
-                       break;
-       }
-
-       return NOTIFY_DONE;
-}
-
-/**
- * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
- * @work: Work structure used for scheduling the execution of this function.
- */
-static void genpd_power_off_work_fn(struct work_struct *work)
-{
-       struct generic_pm_domain *genpd;
-
-       genpd = container_of(work, struct generic_pm_domain, power_off_work);
-
-       genpd_lock(genpd);
-       genpd_power_off(genpd, false, 0);
-       genpd_unlock(genpd);
-}
-
-/**
- * __genpd_runtime_suspend - walk the hierarchy of ->runtime_suspend() callbacks
- * @dev: Device to handle.
- */
-static int __genpd_runtime_suspend(struct device *dev)
-{
-       int (*cb)(struct device *__dev);
-
-       if (dev->type && dev->type->pm)
-               cb = dev->type->pm->runtime_suspend;
-       else if (dev->class && dev->class->pm)
-               cb = dev->class->pm->runtime_suspend;
-       else if (dev->bus && dev->bus->pm)
-               cb = dev->bus->pm->runtime_suspend;
-       else
-               cb = NULL;
-
-       if (!cb && dev->driver && dev->driver->pm)
-               cb = dev->driver->pm->runtime_suspend;
-
-       return cb ? cb(dev) : 0;
-}
-
-/**
- * __genpd_runtime_resume - walk the hierarchy of ->runtime_resume() callbacks
- * @dev: Device to handle.
- */
-static int __genpd_runtime_resume(struct device *dev)
-{
-       int (*cb)(struct device *__dev);
-
-       if (dev->type && dev->type->pm)
-               cb = dev->type->pm->runtime_resume;
-       else if (dev->class && dev->class->pm)
-               cb = dev->class->pm->runtime_resume;
-       else if (dev->bus && dev->bus->pm)
-               cb = dev->bus->pm->runtime_resume;
-       else
-               cb = NULL;
-
-       if (!cb && dev->driver && dev->driver->pm)
-               cb = dev->driver->pm->runtime_resume;
-
-       return cb ? cb(dev) : 0;
-}
-
-/**
- * genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
- * @dev: Device to suspend.
- *
- * Carry out a runtime suspend of a device under the assumption that its
- * pm_domain field points to the domain member of an object of type
- * struct generic_pm_domain representing a PM domain consisting of I/O devices.
- */
-static int genpd_runtime_suspend(struct device *dev)
-{
-       struct generic_pm_domain *genpd;
-       bool (*suspend_ok)(struct device *__dev);
-       struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
-       struct gpd_timing_data *td = gpd_data->td;
-       bool runtime_pm = pm_runtime_enabled(dev);
-       ktime_t time_start = 0;
-       s64 elapsed_ns;
-       int ret;
-
-       dev_dbg(dev, "%s()\n", __func__);
-
-       genpd = dev_to_genpd(dev);
-       if (IS_ERR(genpd))
-               return -EINVAL;
-
-       /*
-        * A runtime PM centric subsystem/driver may re-use the runtime PM
-        * callbacks for other purposes than runtime PM. In those scenarios
-        * runtime PM is disabled. Under these circumstances, we shall skip
-        * validating/measuring the PM QoS latency.
-        */
-       suspend_ok = genpd->gov ? genpd->gov->suspend_ok : NULL;
-       if (runtime_pm && suspend_ok && !suspend_ok(dev))
-               return -EBUSY;
-
-       /* Measure suspend latency. */
-       if (td && runtime_pm)
-               time_start = ktime_get();
-
-       ret = __genpd_runtime_suspend(dev);
-       if (ret)
-               return ret;
-
-       ret = genpd_stop_dev(genpd, dev);
-       if (ret) {
-               __genpd_runtime_resume(dev);
-               return ret;
-       }
-
-       /* Update suspend latency value if the measured time exceeds it. */
-       if (td && runtime_pm) {
-               elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
-               if (elapsed_ns > td->suspend_latency_ns) {
-                       td->suspend_latency_ns = elapsed_ns;
-                       dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
-                               elapsed_ns);
-                       genpd->gd->max_off_time_changed = true;
-                       td->constraint_changed = true;
-               }
-       }
-
-       /*
-        * If power.irq_safe is set, this routine may be run with
-        * IRQs disabled, so suspend only if the PM domain also is irq_safe.
-        */
-       if (irq_safe_dev_in_sleep_domain(dev, genpd))
-               return 0;
-
-       genpd_lock(genpd);
-       genpd_power_off(genpd, true, 0);
-       gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
-       genpd_unlock(genpd);
-
-       return 0;
-}
-
-/**
- * genpd_runtime_resume - Resume a device belonging to I/O PM domain.
- * @dev: Device to resume.
- *
- * Carry out a runtime resume of a device under the assumption that its
- * pm_domain field points to the domain member of an object of type
- * struct generic_pm_domain representing a PM domain consisting of I/O devices.
- */
-static int genpd_runtime_resume(struct device *dev)
-{
-       struct generic_pm_domain *genpd;
-       struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
-       struct gpd_timing_data *td = gpd_data->td;
-       bool timed = td && pm_runtime_enabled(dev);
-       ktime_t time_start = 0;
-       s64 elapsed_ns;
-       int ret;
-
-       dev_dbg(dev, "%s()\n", __func__);
-
-       genpd = dev_to_genpd(dev);
-       if (IS_ERR(genpd))
-               return -EINVAL;
-
-       /*
-        * As we don't power off a non IRQ safe domain, which holds
-        * an IRQ safe device, we don't need to restore power to it.
-        */
-       if (irq_safe_dev_in_sleep_domain(dev, genpd))
-               goto out;
-
-       genpd_lock(genpd);
-       genpd_restore_performance_state(dev, gpd_data->rpm_pstate);
-       ret = genpd_power_on(genpd, 0);
-       genpd_unlock(genpd);
-
-       if (ret)
-               return ret;
-
- out:
-       /* Measure resume latency. */
-       if (timed)
-               time_start = ktime_get();
-
-       ret = genpd_start_dev(genpd, dev);
-       if (ret)
-               goto err_poweroff;
-
-       ret = __genpd_runtime_resume(dev);
-       if (ret)
-               goto err_stop;
-
-       /* Update resume latency value if the measured time exceeds it. */
-       if (timed) {
-               elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
-               if (elapsed_ns > td->resume_latency_ns) {
-                       td->resume_latency_ns = elapsed_ns;
-                       dev_dbg(dev, "resume latency exceeded, %lld ns\n",
-                               elapsed_ns);
-                       genpd->gd->max_off_time_changed = true;
-                       td->constraint_changed = true;
-               }
-       }
-
-       return 0;
-
-err_stop:
-       genpd_stop_dev(genpd, dev);
-err_poweroff:
-       if (!pm_runtime_is_irq_safe(dev) || genpd_is_irq_safe(genpd)) {
-               genpd_lock(genpd);
-               genpd_power_off(genpd, true, 0);
-               gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
-               genpd_unlock(genpd);
-       }
-
-       return ret;
-}
-
-static bool pd_ignore_unused;
-static int __init pd_ignore_unused_setup(char *__unused)
-{
-       pd_ignore_unused = true;
-       return 1;
-}
-__setup("pd_ignore_unused", pd_ignore_unused_setup);
-
-/**
- * genpd_power_off_unused - Power off all PM domains with no devices in use.
- */
-static int __init genpd_power_off_unused(void)
-{
-       struct generic_pm_domain *genpd;
-
-       if (pd_ignore_unused) {
-               pr_warn("genpd: Not disabling unused power domains\n");
-               return 0;
-       }
-
-       mutex_lock(&gpd_list_lock);
-
-       list_for_each_entry(genpd, &gpd_list, gpd_list_node)
-               genpd_queue_power_off_work(genpd);
-
-       mutex_unlock(&gpd_list_lock);
-
-       return 0;
-}
-late_initcall(genpd_power_off_unused);
-
-#ifdef CONFIG_PM_SLEEP
-
-/**
- * genpd_sync_power_off - Synchronously power off a PM domain and its parents.
- * @genpd: PM domain to power off, if possible.
- * @use_lock: use the lock.
- * @depth: nesting count for lockdep.
- *
- * Check if the given PM domain can be powered off (during system suspend or
- * hibernation) and do that if so.  Also, in that case propagate to its parents.
- *
- * This function is only called in "noirq" and "syscore" stages of system power
- * transitions. The "noirq" callbacks may be executed asynchronously, thus in
- * these cases the lock must be held.
- */
-static void genpd_sync_power_off(struct generic_pm_domain *genpd, bool use_lock,
-                                unsigned int depth)
-{
-       struct gpd_link *link;
-
-       if (!genpd_status_on(genpd) || genpd_is_always_on(genpd))
-               return;
-
-       if (genpd->suspended_count != genpd->device_count
-           || atomic_read(&genpd->sd_count) > 0)
-               return;
-
-       /* Check that the children are in their deepest (powered-off) state. */
-       list_for_each_entry(link, &genpd->parent_links, parent_node) {
-               struct generic_pm_domain *child = link->child;
-               if (child->state_idx < child->state_count - 1)
-                       return;
-       }
-
-       /* Choose the deepest state when suspending */
-       genpd->state_idx = genpd->state_count - 1;
-       if (_genpd_power_off(genpd, false))
-               return;
-
-       genpd->status = GENPD_STATE_OFF;
-
-       list_for_each_entry(link, &genpd->child_links, child_node) {
-               genpd_sd_counter_dec(link->parent);
-
-               if (use_lock)
-                       genpd_lock_nested(link->parent, depth + 1);
-
-               genpd_sync_power_off(link->parent, use_lock, depth + 1);
-
-               if (use_lock)
-                       genpd_unlock(link->parent);
-       }
-}
-
-/**
- * genpd_sync_power_on - Synchronously power on a PM domain and its parents.
- * @genpd: PM domain to power on.
- * @use_lock: use the lock.
- * @depth: nesting count for lockdep.
- *
- * This function is only called in "noirq" and "syscore" stages of system power
- * transitions. The "noirq" callbacks may be executed asynchronously, thus in
- * these cases the lock must be held.
- */
-static void genpd_sync_power_on(struct generic_pm_domain *genpd, bool use_lock,
-                               unsigned int depth)
-{
-       struct gpd_link *link;
-
-       if (genpd_status_on(genpd))
-               return;
-
-       list_for_each_entry(link, &genpd->child_links, child_node) {
-               genpd_sd_counter_inc(link->parent);
-
-               if (use_lock)
-                       genpd_lock_nested(link->parent, depth + 1);
-
-               genpd_sync_power_on(link->parent, use_lock, depth + 1);
-
-               if (use_lock)
-                       genpd_unlock(link->parent);
-       }
-
-       _genpd_power_on(genpd, false);
-       genpd->status = GENPD_STATE_ON;
-}
-
-/**
- * genpd_prepare - Start power transition of a device in a PM domain.
- * @dev: Device to start the transition of.
- *
- * Start a power transition of a device (during a system-wide power transition)
- * under the assumption that its pm_domain field points to the domain member of
- * an object of type struct generic_pm_domain representing a PM domain
- * consisting of I/O devices.
- */
-static int genpd_prepare(struct device *dev)
-{
-       struct generic_pm_domain *genpd;
-       int ret;
-
-       dev_dbg(dev, "%s()\n", __func__);
-
-       genpd = dev_to_genpd(dev);
-       if (IS_ERR(genpd))
-               return -EINVAL;
-
-       genpd_lock(genpd);
-
-       if (genpd->prepared_count++ == 0)
-               genpd->suspended_count = 0;
-
-       genpd_unlock(genpd);
-
-       ret = pm_generic_prepare(dev);
-       if (ret < 0) {
-               genpd_lock(genpd);
-
-               genpd->prepared_count--;
-
-               genpd_unlock(genpd);
-       }
-
-       /* Never return 1, as genpd don't cope with the direct_complete path. */
-       return ret >= 0 ? 0 : ret;
-}
-
-/**
- * genpd_finish_suspend - Completion of suspend or hibernation of device in an
- *   I/O pm domain.
- * @dev: Device to suspend.
- * @suspend_noirq: Generic suspend_noirq callback.
- * @resume_noirq: Generic resume_noirq callback.
- *
- * Stop the device and remove power from the domain if all devices in it have
- * been stopped.
- */
-static int genpd_finish_suspend(struct device *dev,
-                               int (*suspend_noirq)(struct device *dev),
-                               int (*resume_noirq)(struct device *dev))
-{
-       struct generic_pm_domain *genpd;
-       int ret = 0;
-
-       genpd = dev_to_genpd(dev);
-       if (IS_ERR(genpd))
-               return -EINVAL;
-
-       ret = suspend_noirq(dev);
-       if (ret)
-               return ret;
-
-       if (device_wakeup_path(dev) && genpd_is_active_wakeup(genpd))
-               return 0;
-
-       if (genpd->dev_ops.stop && genpd->dev_ops.start &&
-           !pm_runtime_status_suspended(dev)) {
-               ret = genpd_stop_dev(genpd, dev);
-               if (ret) {
-                       resume_noirq(dev);
-                       return ret;
-               }
-       }
-
-       genpd_lock(genpd);
-       genpd->suspended_count++;
-       genpd_sync_power_off(genpd, true, 0);
-       genpd_unlock(genpd);
-
-       return 0;
-}
-
-/**
- * genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
- * @dev: Device to suspend.
- *
- * Stop the device and remove power from the domain if all devices in it have
- * been stopped.
- */
-static int genpd_suspend_noirq(struct device *dev)
-{
-       dev_dbg(dev, "%s()\n", __func__);
-
-       return genpd_finish_suspend(dev,
-                                   pm_generic_suspend_noirq,
-                                   pm_generic_resume_noirq);
-}
-
-/**
- * genpd_finish_resume - Completion of resume of device in an I/O PM domain.
- * @dev: Device to resume.
- * @resume_noirq: Generic resume_noirq callback.
- *
- * Restore power to the device's PM domain, if necessary, and start the device.
- */
-static int genpd_finish_resume(struct device *dev,
-                              int (*resume_noirq)(struct device *dev))
-{
-       struct generic_pm_domain *genpd;
-       int ret;
-
-       dev_dbg(dev, "%s()\n", __func__);
-
-       genpd = dev_to_genpd(dev);
-       if (IS_ERR(genpd))
-               return -EINVAL;
-
-       if (device_wakeup_path(dev) && genpd_is_active_wakeup(genpd))
-               return resume_noirq(dev);
-
-       genpd_lock(genpd);
-       genpd_sync_power_on(genpd, true, 0);
-       genpd->suspended_count--;
-       genpd_unlock(genpd);
-
-       if (genpd->dev_ops.stop && genpd->dev_ops.start &&
-           !pm_runtime_status_suspended(dev)) {
-               ret = genpd_start_dev(genpd, dev);
-               if (ret)
-                       return ret;
-       }
-
-       return pm_generic_resume_noirq(dev);
-}
-
-/**
- * genpd_resume_noirq - Start of resume of device in an I/O PM domain.
- * @dev: Device to resume.
- *
- * Restore power to the device's PM domain, if necessary, and start the device.
- */
-static int genpd_resume_noirq(struct device *dev)
-{
-       dev_dbg(dev, "%s()\n", __func__);
-
-       return genpd_finish_resume(dev, pm_generic_resume_noirq);
-}
-
-/**
- * genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
- * @dev: Device to freeze.
- *
- * Carry out a late freeze of a device under the assumption that its
- * pm_domain field points to the domain member of an object of type
- * struct generic_pm_domain representing a power domain consisting of I/O
- * devices.
- */
-static int genpd_freeze_noirq(struct device *dev)
-{
-       dev_dbg(dev, "%s()\n", __func__);
-
-       return genpd_finish_suspend(dev,
-                                   pm_generic_freeze_noirq,
-                                   pm_generic_thaw_noirq);
-}
-
-/**
- * genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
- * @dev: Device to thaw.
- *
- * Start the device, unless power has been removed from the domain already
- * before the system transition.
- */
-static int genpd_thaw_noirq(struct device *dev)
-{
-       dev_dbg(dev, "%s()\n", __func__);
-
-       return genpd_finish_resume(dev, pm_generic_thaw_noirq);
-}
-
-/**
- * genpd_poweroff_noirq - Completion of hibernation of device in an
- *   I/O PM domain.
- * @dev: Device to poweroff.
- *
- * Stop the device and remove power from the domain if all devices in it have
- * been stopped.
- */
-static int genpd_poweroff_noirq(struct device *dev)
-{
-       dev_dbg(dev, "%s()\n", __func__);
-
-       return genpd_finish_suspend(dev,
-                                   pm_generic_poweroff_noirq,
-                                   pm_generic_restore_noirq);
-}
-
-/**
- * genpd_restore_noirq - Start of restore of device in an I/O PM domain.
- * @dev: Device to resume.
- *
- * Make sure the domain will be in the same power state as before the
- * hibernation the system is resuming from and start the device if necessary.
- */
-static int genpd_restore_noirq(struct device *dev)
-{
-       dev_dbg(dev, "%s()\n", __func__);
-
-       return genpd_finish_resume(dev, pm_generic_restore_noirq);
-}
-
-/**
- * genpd_complete - Complete power transition of a device in a power domain.
- * @dev: Device to complete the transition of.
- *
- * Complete a power transition of a device (during a system-wide power
- * transition) under the assumption that its pm_domain field points to the
- * domain member of an object of type struct generic_pm_domain representing
- * a power domain consisting of I/O devices.
- */
-static void genpd_complete(struct device *dev)
-{
-       struct generic_pm_domain *genpd;
-
-       dev_dbg(dev, "%s()\n", __func__);
-
-       genpd = dev_to_genpd(dev);
-       if (IS_ERR(genpd))
-               return;
-
-       pm_generic_complete(dev);
-
-       genpd_lock(genpd);
-
-       genpd->prepared_count--;
-       if (!genpd->prepared_count)
-               genpd_queue_power_off_work(genpd);
-
-       genpd_unlock(genpd);
-}
-
-static void genpd_switch_state(struct device *dev, bool suspend)
-{
-       struct generic_pm_domain *genpd;
-       bool use_lock;
-
-       genpd = dev_to_genpd_safe(dev);
-       if (!genpd)
-               return;
-
-       use_lock = genpd_is_irq_safe(genpd);
-
-       if (use_lock)
-               genpd_lock(genpd);
-
-       if (suspend) {
-               genpd->suspended_count++;
-               genpd_sync_power_off(genpd, use_lock, 0);
-       } else {
-               genpd_sync_power_on(genpd, use_lock, 0);
-               genpd->suspended_count--;
-       }
-
-       if (use_lock)
-               genpd_unlock(genpd);
-}
-
-/**
- * dev_pm_genpd_suspend - Synchronously try to suspend the genpd for @dev
- * @dev: The device that is attached to the genpd, that can be suspended.
- *
- * This routine should typically be called for a device that needs to be
- * suspended during the syscore suspend phase. It may also be called during
- * suspend-to-idle to suspend a corresponding CPU device that is attached to a
- * genpd.
- */
-void dev_pm_genpd_suspend(struct device *dev)
-{
-       genpd_switch_state(dev, true);
-}
-EXPORT_SYMBOL_GPL(dev_pm_genpd_suspend);
-
-/**
- * dev_pm_genpd_resume - Synchronously try to resume the genpd for @dev
- * @dev: The device that is attached to the genpd, which needs to be resumed.
- *
- * This routine should typically be called for a device that needs to be resumed
- * during the syscore resume phase. It may also be called during suspend-to-idle
- * to resume a corresponding CPU device that is attached to a genpd.
- */
-void dev_pm_genpd_resume(struct device *dev)
-{
-       genpd_switch_state(dev, false);
-}
-EXPORT_SYMBOL_GPL(dev_pm_genpd_resume);
-
-#else /* !CONFIG_PM_SLEEP */
-
-#define genpd_prepare          NULL
-#define genpd_suspend_noirq    NULL
-#define genpd_resume_noirq     NULL
-#define genpd_freeze_noirq     NULL
-#define genpd_thaw_noirq       NULL
-#define genpd_poweroff_noirq   NULL
-#define genpd_restore_noirq    NULL
-#define genpd_complete         NULL
-
-#endif /* CONFIG_PM_SLEEP */
-
-static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
-                                                          bool has_governor)
-{
-       struct generic_pm_domain_data *gpd_data;
-       struct gpd_timing_data *td;
-       int ret;
-
-       ret = dev_pm_get_subsys_data(dev);
-       if (ret)
-               return ERR_PTR(ret);
-
-       gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
-       if (!gpd_data) {
-               ret = -ENOMEM;
-               goto err_put;
-       }
-
-       gpd_data->base.dev = dev;
-       gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
-
-       /* Allocate data used by a governor. */
-       if (has_governor) {
-               td = kzalloc(sizeof(*td), GFP_KERNEL);
-               if (!td) {
-                       ret = -ENOMEM;
-                       goto err_free;
-               }
-
-               td->constraint_changed = true;
-               td->effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
-               td->next_wakeup = KTIME_MAX;
-               gpd_data->td = td;
-       }
-
-       spin_lock_irq(&dev->power.lock);
-
-       if (dev->power.subsys_data->domain_data)
-               ret = -EINVAL;
-       else
-               dev->power.subsys_data->domain_data = &gpd_data->base;
-
-       spin_unlock_irq(&dev->power.lock);
-
-       if (ret)
-               goto err_free;
-
-       return gpd_data;
-
- err_free:
-       kfree(gpd_data->td);
-       kfree(gpd_data);
- err_put:
-       dev_pm_put_subsys_data(dev);
-       return ERR_PTR(ret);
-}
-
-static void genpd_free_dev_data(struct device *dev,
-                               struct generic_pm_domain_data *gpd_data)
-{
-       spin_lock_irq(&dev->power.lock);
-
-       dev->power.subsys_data->domain_data = NULL;
-
-       spin_unlock_irq(&dev->power.lock);
-
-       kfree(gpd_data->td);
-       kfree(gpd_data);
-       dev_pm_put_subsys_data(dev);
-}
-
-static void genpd_update_cpumask(struct generic_pm_domain *genpd,
-                                int cpu, bool set, unsigned int depth)
-{
-       struct gpd_link *link;
-
-       if (!genpd_is_cpu_domain(genpd))
-               return;
-
-       list_for_each_entry(link, &genpd->child_links, child_node) {
-               struct generic_pm_domain *parent = link->parent;
-
-               genpd_lock_nested(parent, depth + 1);
-               genpd_update_cpumask(parent, cpu, set, depth + 1);
-               genpd_unlock(parent);
-       }
-
-       if (set)
-               cpumask_set_cpu(cpu, genpd->cpus);
-       else
-               cpumask_clear_cpu(cpu, genpd->cpus);
-}
-
-static void genpd_set_cpumask(struct generic_pm_domain *genpd, int cpu)
-{
-       if (cpu >= 0)
-               genpd_update_cpumask(genpd, cpu, true, 0);
-}
-
-static void genpd_clear_cpumask(struct generic_pm_domain *genpd, int cpu)
-{
-       if (cpu >= 0)
-               genpd_update_cpumask(genpd, cpu, false, 0);
-}
-
-static int genpd_get_cpu(struct generic_pm_domain *genpd, struct device *dev)
-{
-       int cpu;
-
-       if (!genpd_is_cpu_domain(genpd))
-               return -1;
-
-       for_each_possible_cpu(cpu) {
-               if (get_cpu_device(cpu) == dev)
-                       return cpu;
-       }
-
-       return -1;
-}
-
-static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
-                           struct device *base_dev)
-{
-       struct genpd_governor_data *gd = genpd->gd;
-       struct generic_pm_domain_data *gpd_data;
-       int ret;
-
-       dev_dbg(dev, "%s()\n", __func__);
-
-       gpd_data = genpd_alloc_dev_data(dev, gd);
-       if (IS_ERR(gpd_data))
-               return PTR_ERR(gpd_data);
-
-       gpd_data->cpu = genpd_get_cpu(genpd, base_dev);
-
-       ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
-       if (ret)
-               goto out;
-
-       genpd_lock(genpd);
-
-       genpd_set_cpumask(genpd, gpd_data->cpu);
-       dev_pm_domain_set(dev, &genpd->domain);
-
-       genpd->device_count++;
-       if (gd)
-               gd->max_off_time_changed = true;
-
-       list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
-
-       genpd_unlock(genpd);
- out:
-       if (ret)
-               genpd_free_dev_data(dev, gpd_data);
-       else
-               dev_pm_qos_add_notifier(dev, &gpd_data->nb,
-                                       DEV_PM_QOS_RESUME_LATENCY);
-
-       return ret;
-}
-
-/**
- * pm_genpd_add_device - Add a device to an I/O PM domain.
- * @genpd: PM domain to add the device to.
- * @dev: Device to be added.
- */
-int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev)
-{
-       int ret;
-
-       if (!genpd || !dev)
-               return -EINVAL;
-
-       mutex_lock(&gpd_list_lock);
-       ret = genpd_add_device(genpd, dev, dev);
-       mutex_unlock(&gpd_list_lock);
-
-       return ret;
-}
-EXPORT_SYMBOL_GPL(pm_genpd_add_device);
-
-static int genpd_remove_device(struct generic_pm_domain *genpd,
-                              struct device *dev)
-{
-       struct generic_pm_domain_data *gpd_data;
-       struct pm_domain_data *pdd;
-       int ret = 0;
-
-       dev_dbg(dev, "%s()\n", __func__);
-
-       pdd = dev->power.subsys_data->domain_data;
-       gpd_data = to_gpd_data(pdd);
-       dev_pm_qos_remove_notifier(dev, &gpd_data->nb,
-                                  DEV_PM_QOS_RESUME_LATENCY);
-
-       genpd_lock(genpd);
-
-       if (genpd->prepared_count > 0) {
-               ret = -EAGAIN;
-               goto out;
-       }
-
-       genpd->device_count--;
-       if (genpd->gd)
-               genpd->gd->max_off_time_changed = true;
-
-       genpd_clear_cpumask(genpd, gpd_data->cpu);
-       dev_pm_domain_set(dev, NULL);
-
-       list_del_init(&pdd->list_node);
-
-       genpd_unlock(genpd);
-
-       if (genpd->detach_dev)
-               genpd->detach_dev(genpd, dev);
-
-       genpd_free_dev_data(dev, gpd_data);
-
-       return 0;
-
- out:
-       genpd_unlock(genpd);
-       dev_pm_qos_add_notifier(dev, &gpd_data->nb, DEV_PM_QOS_RESUME_LATENCY);
-
-       return ret;
-}
-
-/**
- * pm_genpd_remove_device - Remove a device from an I/O PM domain.
- * @dev: Device to be removed.
- */
-int pm_genpd_remove_device(struct device *dev)
-{
-       struct generic_pm_domain *genpd = dev_to_genpd_safe(dev);
-
-       if (!genpd)
-               return -EINVAL;
-
-       return genpd_remove_device(genpd, dev);
-}
-EXPORT_SYMBOL_GPL(pm_genpd_remove_device);
-
-/**
- * dev_pm_genpd_add_notifier - Add a genpd power on/off notifier for @dev
- *
- * @dev: Device that should be associated with the notifier
- * @nb: The notifier block to register
- *
- * Users may call this function to add a genpd power on/off notifier for an
- * attached @dev. Only one notifier per device is allowed. The notifier is
- * sent when genpd is powering on/off the PM domain.
- *
- * It is assumed that the user guarantee that the genpd wouldn't be detached
- * while this routine is getting called.
- *
- * Returns 0 on success and negative error values on failures.
- */
-int dev_pm_genpd_add_notifier(struct device *dev, struct notifier_block *nb)
-{
-       struct generic_pm_domain *genpd;
-       struct generic_pm_domain_data *gpd_data;
-       int ret;
-
-       genpd = dev_to_genpd_safe(dev);
-       if (!genpd)
-               return -ENODEV;
-
-       if (WARN_ON(!dev->power.subsys_data ||
-                    !dev->power.subsys_data->domain_data))
-               return -EINVAL;
-
-       gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
-       if (gpd_data->power_nb)
-               return -EEXIST;
-
-       genpd_lock(genpd);
-       ret = raw_notifier_chain_register(&genpd->power_notifiers, nb);
-       genpd_unlock(genpd);
-
-       if (ret) {
-               dev_warn(dev, "failed to add notifier for PM domain %s\n",
-                        genpd->name);
-               return ret;
-       }
-
-       gpd_data->power_nb = nb;
-       return 0;
-}
-EXPORT_SYMBOL_GPL(dev_pm_genpd_add_notifier);
-
-/**
- * dev_pm_genpd_remove_notifier - Remove a genpd power on/off notifier for @dev
- *
- * @dev: Device that is associated with the notifier
- *
- * Users may call this function to remove a genpd power on/off notifier for an
- * attached @dev.
- *
- * It is assumed that the user guarantee that the genpd wouldn't be detached
- * while this routine is getting called.
- *
- * Returns 0 on success and negative error values on failures.
- */
-int dev_pm_genpd_remove_notifier(struct device *dev)
-{
-       struct generic_pm_domain *genpd;
-       struct generic_pm_domain_data *gpd_data;
-       int ret;
-
-       genpd = dev_to_genpd_safe(dev);
-       if (!genpd)
-               return -ENODEV;
-
-       if (WARN_ON(!dev->power.subsys_data ||
-                    !dev->power.subsys_data->domain_data))
-               return -EINVAL;
-
-       gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
-       if (!gpd_data->power_nb)
-               return -ENODEV;
-
-       genpd_lock(genpd);
-       ret = raw_notifier_chain_unregister(&genpd->power_notifiers,
-                                           gpd_data->power_nb);
-       genpd_unlock(genpd);
-
-       if (ret) {
-               dev_warn(dev, "failed to remove notifier for PM domain %s\n",
-                        genpd->name);
-               return ret;
-       }
-
-       gpd_data->power_nb = NULL;
-       return 0;
-}
-EXPORT_SYMBOL_GPL(dev_pm_genpd_remove_notifier);
-
-static int genpd_add_subdomain(struct generic_pm_domain *genpd,
-                              struct generic_pm_domain *subdomain)
-{
-       struct gpd_link *link, *itr;
-       int ret = 0;
-
-       if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
-           || genpd == subdomain)
-               return -EINVAL;
-
-       /*
-        * If the domain can be powered on/off in an IRQ safe
-        * context, ensure that the subdomain can also be
-        * powered on/off in that context.
-        */
-       if (!genpd_is_irq_safe(genpd) && genpd_is_irq_safe(subdomain)) {
-               WARN(1, "Parent %s of subdomain %s must be IRQ safe\n",
-                               genpd->name, subdomain->name);
-               return -EINVAL;
-       }
-
-       link = kzalloc(sizeof(*link), GFP_KERNEL);
-       if (!link)
-               return -ENOMEM;
-
-       genpd_lock(subdomain);
-       genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
-
-       if (!genpd_status_on(genpd) && genpd_status_on(subdomain)) {
-               ret = -EINVAL;
-               goto out;
-       }
-
-       list_for_each_entry(itr, &genpd->parent_links, parent_node) {
-               if (itr->child == subdomain && itr->parent == genpd) {
-                       ret = -EINVAL;
-                       goto out;
-               }
-       }
-
-       link->parent = genpd;
-       list_add_tail(&link->parent_node, &genpd->parent_links);
-       link->child = subdomain;
-       list_add_tail(&link->child_node, &subdomain->child_links);
-       if (genpd_status_on(subdomain))
-               genpd_sd_counter_inc(genpd);
-
- out:
-       genpd_unlock(genpd);
-       genpd_unlock(subdomain);
-       if (ret)
-               kfree(link);
-       return ret;
-}
-
-/**
- * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
- * @genpd: Leader PM domain to add the subdomain to.
- * @subdomain: Subdomain to be added.
- */
-int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
-                          struct generic_pm_domain *subdomain)
-{
-       int ret;
-
-       mutex_lock(&gpd_list_lock);
-       ret = genpd_add_subdomain(genpd, subdomain);
-       mutex_unlock(&gpd_list_lock);
-
-       return ret;
-}
-EXPORT_SYMBOL_GPL(pm_genpd_add_subdomain);
-
-/**
- * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
- * @genpd: Leader PM domain to remove the subdomain from.
- * @subdomain: Subdomain to be removed.
- */
-int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
-                             struct generic_pm_domain *subdomain)
-{
-       struct gpd_link *l, *link;
-       int ret = -EINVAL;
-
-       if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
-               return -EINVAL;
-
-       genpd_lock(subdomain);
-       genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
-
-       if (!list_empty(&subdomain->parent_links) || subdomain->device_count) {
-               pr_warn("%s: unable to remove subdomain %s\n",
-                       genpd->name, subdomain->name);
-               ret = -EBUSY;
-               goto out;
-       }
-
-       list_for_each_entry_safe(link, l, &genpd->parent_links, parent_node) {
-               if (link->child != subdomain)
-                       continue;
-
-               list_del(&link->parent_node);
-               list_del(&link->child_node);
-               kfree(link);
-               if (genpd_status_on(subdomain))
-                       genpd_sd_counter_dec(genpd);
-
-               ret = 0;
-               break;
-       }
-
-out:
-       genpd_unlock(genpd);
-       genpd_unlock(subdomain);
-
-       return ret;
-}
-EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain);
-
-static void genpd_free_default_power_state(struct genpd_power_state *states,
-                                          unsigned int state_count)
-{
-       kfree(states);
-}
-
-static int genpd_set_default_power_state(struct generic_pm_domain *genpd)
-{
-       struct genpd_power_state *state;
-
-       state = kzalloc(sizeof(*state), GFP_KERNEL);
-       if (!state)
-               return -ENOMEM;
-
-       genpd->states = state;
-       genpd->state_count = 1;
-       genpd->free_states = genpd_free_default_power_state;
-
-       return 0;
-}
-
-static int genpd_alloc_data(struct generic_pm_domain *genpd)
-{
-       struct genpd_governor_data *gd = NULL;
-       int ret;
-
-       if (genpd_is_cpu_domain(genpd) &&
-           !zalloc_cpumask_var(&genpd->cpus, GFP_KERNEL))
-               return -ENOMEM;
-
-       if (genpd->gov) {
-               gd = kzalloc(sizeof(*gd), GFP_KERNEL);
-               if (!gd) {
-                       ret = -ENOMEM;
-                       goto free;
-               }
-
-               gd->max_off_time_ns = -1;
-               gd->max_off_time_changed = true;
-               gd->next_wakeup = KTIME_MAX;
-               gd->next_hrtimer = KTIME_MAX;
-       }
-
-       /* Use only one "off" state if there were no states declared */
-       if (genpd->state_count == 0) {
-               ret = genpd_set_default_power_state(genpd);
-               if (ret)
-                       goto free;
-       }
-
-       genpd->gd = gd;
-       return 0;
-
-free:
-       if (genpd_is_cpu_domain(genpd))
-               free_cpumask_var(genpd->cpus);
-       kfree(gd);
-       return ret;
-}
-
-static void genpd_free_data(struct generic_pm_domain *genpd)
-{
-       if (genpd_is_cpu_domain(genpd))
-               free_cpumask_var(genpd->cpus);
-       if (genpd->free_states)
-               genpd->free_states(genpd->states, genpd->state_count);
-       kfree(genpd->gd);
-}
-
-static void genpd_lock_init(struct generic_pm_domain *genpd)
-{
-       if (genpd->flags & GENPD_FLAG_IRQ_SAFE) {
-               spin_lock_init(&genpd->slock);
-               genpd->lock_ops = &genpd_spin_ops;
-       } else {
-               mutex_init(&genpd->mlock);
-               genpd->lock_ops = &genpd_mtx_ops;
-       }
-}
-
-/**
- * pm_genpd_init - Initialize a generic I/O PM domain object.
- * @genpd: PM domain object to initialize.
- * @gov: PM domain governor to associate with the domain (may be NULL).
- * @is_off: Initial value of the domain's power_is_off field.
- *
- * Returns 0 on successful initialization, else a negative error code.
- */
-int pm_genpd_init(struct generic_pm_domain *genpd,
-                 struct dev_power_governor *gov, bool is_off)
-{
-       int ret;
-
-       if (IS_ERR_OR_NULL(genpd))
-               return -EINVAL;
-
-       INIT_LIST_HEAD(&genpd->parent_links);
-       INIT_LIST_HEAD(&genpd->child_links);
-       INIT_LIST_HEAD(&genpd->dev_list);
-       RAW_INIT_NOTIFIER_HEAD(&genpd->power_notifiers);
-       genpd_lock_init(genpd);
-       genpd->gov = gov;
-       INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
-       atomic_set(&genpd->sd_count, 0);
-       genpd->status = is_off ? GENPD_STATE_OFF : GENPD_STATE_ON;
-       genpd->device_count = 0;
-       genpd->provider = NULL;
-       genpd->has_provider = false;
-       genpd->accounting_time = ktime_get_mono_fast_ns();
-       genpd->domain.ops.runtime_suspend = genpd_runtime_suspend;
-       genpd->domain.ops.runtime_resume = genpd_runtime_resume;
-       genpd->domain.ops.prepare = genpd_prepare;
-       genpd->domain.ops.suspend_noirq = genpd_suspend_noirq;
-       genpd->domain.ops.resume_noirq = genpd_resume_noirq;
-       genpd->domain.ops.freeze_noirq = genpd_freeze_noirq;
-       genpd->domain.ops.thaw_noirq = genpd_thaw_noirq;
-       genpd->domain.ops.poweroff_noirq = genpd_poweroff_noirq;
-       genpd->domain.ops.restore_noirq = genpd_restore_noirq;
-       genpd->domain.ops.complete = genpd_complete;
-       genpd->domain.start = genpd_dev_pm_start;
-       genpd->domain.set_performance_state = genpd_dev_pm_set_performance_state;
-
-       if (genpd->flags & GENPD_FLAG_PM_CLK) {
-               genpd->dev_ops.stop = pm_clk_suspend;
-               genpd->dev_ops.start = pm_clk_resume;
-       }
-
-       /* The always-on governor works better with the corresponding flag. */
-       if (gov == &pm_domain_always_on_gov)
-               genpd->flags |= GENPD_FLAG_RPM_ALWAYS_ON;
-
-       /* Always-on domains must be powered on at initialization. */
-       if ((genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd)) &&
-                       !genpd_status_on(genpd)) {
-               pr_err("always-on PM domain %s is not on\n", genpd->name);
-               return -EINVAL;
-       }
-
-       /* Multiple states but no governor doesn't make sense. */
-       if (!gov && genpd->state_count > 1)
-               pr_warn("%s: no governor for states\n", genpd->name);
-
-       ret = genpd_alloc_data(genpd);
-       if (ret)
-               return ret;
-
-       device_initialize(&genpd->dev);
-       dev_set_name(&genpd->dev, "%s", genpd->name);
-
-       mutex_lock(&gpd_list_lock);
-       list_add(&genpd->gpd_list_node, &gpd_list);
-       mutex_unlock(&gpd_list_lock);
-       genpd_debug_add(genpd);
-
-       return 0;
-}
-EXPORT_SYMBOL_GPL(pm_genpd_init);
-
-static int genpd_remove(struct generic_pm_domain *genpd)
-{
-       struct gpd_link *l, *link;
-
-       if (IS_ERR_OR_NULL(genpd))
-               return -EINVAL;
-
-       genpd_lock(genpd);
-
-       if (genpd->has_provider) {
-               genpd_unlock(genpd);
-               pr_err("Provider present, unable to remove %s\n", genpd->name);
-               return -EBUSY;
-       }
-
-       if (!list_empty(&genpd->parent_links) || genpd->device_count) {
-               genpd_unlock(genpd);
-               pr_err("%s: unable to remove %s\n", __func__, genpd->name);
-               return -EBUSY;
-       }
-
-       list_for_each_entry_safe(link, l, &genpd->child_links, child_node) {
-               list_del(&link->parent_node);
-               list_del(&link->child_node);
-               kfree(link);
-       }
-
-       list_del(&genpd->gpd_list_node);
-       genpd_unlock(genpd);
-       genpd_debug_remove(genpd);
-       cancel_work_sync(&genpd->power_off_work);
-       genpd_free_data(genpd);
-
-       pr_debug("%s: removed %s\n", __func__, genpd->name);
-
-       return 0;
-}
-
-/**
- * pm_genpd_remove - Remove a generic I/O PM domain
- * @genpd: Pointer to PM domain that is to be removed.
- *
- * To remove the PM domain, this function:
- *  - Removes the PM domain as a subdomain to any parent domains,
- *    if it was added.
- *  - Removes the PM domain from the list of registered PM domains.
- *
- * The PM domain will only be removed, if the associated provider has
- * been removed, it is not a parent to any other PM domain and has no
- * devices associated with it.
- */
-int pm_genpd_remove(struct generic_pm_domain *genpd)
-{
-       int ret;
-
-       mutex_lock(&gpd_list_lock);
-       ret = genpd_remove(genpd);
-       mutex_unlock(&gpd_list_lock);
-
-       return ret;
-}
-EXPORT_SYMBOL_GPL(pm_genpd_remove);
-
-#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
-
-/*
- * Device Tree based PM domain providers.
- *
- * The code below implements generic device tree based PM domain providers that
- * bind device tree nodes with generic PM domains registered in the system.
- *
- * Any driver that registers generic PM domains and needs to support binding of
- * devices to these domains is supposed to register a PM domain provider, which
- * maps a PM domain specifier retrieved from the device tree to a PM domain.
- *
- * Two simple mapping functions have been provided for convenience:
- *  - genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
- *  - genpd_xlate_onecell() for mapping of multiple PM domains per node by
- *    index.
- */
-
-/**
- * struct of_genpd_provider - PM domain provider registration structure
- * @link: Entry in global list of PM domain providers
- * @node: Pointer to device tree node of PM domain provider
- * @xlate: Provider-specific xlate callback mapping a set of specifier cells
- *         into a PM domain.
- * @data: context pointer to be passed into @xlate callback
- */
-struct of_genpd_provider {
-       struct list_head link;
-       struct device_node *node;
-       genpd_xlate_t xlate;
-       void *data;
-};
-
-/* List of registered PM domain providers. */
-static LIST_HEAD(of_genpd_providers);
-/* Mutex to protect the list above. */
-static DEFINE_MUTEX(of_genpd_mutex);
-
-/**
- * genpd_xlate_simple() - Xlate function for direct node-domain mapping
- * @genpdspec: OF phandle args to map into a PM domain
- * @data: xlate function private data - pointer to struct generic_pm_domain
- *
- * This is a generic xlate function that can be used to model PM domains that
- * have their own device tree nodes. The private data of xlate function needs
- * to be a valid pointer to struct generic_pm_domain.
- */
-static struct generic_pm_domain *genpd_xlate_simple(
-                                       struct of_phandle_args *genpdspec,
-                                       void *data)
-{
-       return data;
-}
-
-/**
- * genpd_xlate_onecell() - Xlate function using a single index.
- * @genpdspec: OF phandle args to map into a PM domain
- * @data: xlate function private data - pointer to struct genpd_onecell_data
- *
- * This is a generic xlate function that can be used to model simple PM domain
- * controllers that have one device tree node and provide multiple PM domains.
- * A single cell is used as an index into an array of PM domains specified in
- * the genpd_onecell_data struct when registering the provider.
- */
-static struct generic_pm_domain *genpd_xlate_onecell(
-                                       struct of_phandle_args *genpdspec,
-                                       void *data)
-{
-       struct genpd_onecell_data *genpd_data = data;
-       unsigned int idx = genpdspec->args[0];
-
-       if (genpdspec->args_count != 1)
-               return ERR_PTR(-EINVAL);
-
-       if (idx >= genpd_data->num_domains) {
-               pr_err("%s: invalid domain index %u\n", __func__, idx);
-               return ERR_PTR(-EINVAL);
-       }
-
-       if (!genpd_data->domains[idx])
-               return ERR_PTR(-ENOENT);
-
-       return genpd_data->domains[idx];
-}
-
-/**
- * genpd_add_provider() - Register a PM domain provider for a node
- * @np: Device node pointer associated with the PM domain provider.
- * @xlate: Callback for decoding PM domain from phandle arguments.
- * @data: Context pointer for @xlate callback.
- */
-static int genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
-                             void *data)
-{
-       struct of_genpd_provider *cp;
-
-       cp = kzalloc(sizeof(*cp), GFP_KERNEL);
-       if (!cp)
-               return -ENOMEM;
-
-       cp->node = of_node_get(np);
-       cp->data = data;
-       cp->xlate = xlate;
-       fwnode_dev_initialized(&np->fwnode, true);
-
-       mutex_lock(&of_genpd_mutex);
-       list_add(&cp->link, &of_genpd_providers);
-       mutex_unlock(&of_genpd_mutex);
-       pr_debug("Added domain provider from %pOF\n", np);
-
-       return 0;
-}
-
-static bool genpd_present(const struct generic_pm_domain *genpd)
-{
-       bool ret = false;
-       const struct generic_pm_domain *gpd;
-
-       mutex_lock(&gpd_list_lock);
-       list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
-               if (gpd == genpd) {
-                       ret = true;
-                       break;
-               }
-       }
-       mutex_unlock(&gpd_list_lock);
-
-       return ret;
-}
-
-/**
- * of_genpd_add_provider_simple() - Register a simple PM domain provider
- * @np: Device node pointer associated with the PM domain provider.
- * @genpd: Pointer to PM domain associated with the PM domain provider.
- */
-int of_genpd_add_provider_simple(struct device_node *np,
-                                struct generic_pm_domain *genpd)
-{
-       int ret;
-
-       if (!np || !genpd)
-               return -EINVAL;
-
-       if (!genpd_present(genpd))
-               return -EINVAL;
-
-       genpd->dev.of_node = np;
-
-       /* Parse genpd OPP table */
-       if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
-               ret = dev_pm_opp_of_add_table(&genpd->dev);
-               if (ret)
-                       return dev_err_probe(&genpd->dev, ret, "Failed to add OPP table\n");
-
-               /*
-                * Save table for faster processing while setting performance
-                * state.
-                */
-               genpd->opp_table = dev_pm_opp_get_opp_table(&genpd->dev);
-               WARN_ON(IS_ERR(genpd->opp_table));
-       }
-
-       ret = genpd_add_provider(np, genpd_xlate_simple, genpd);
-       if (ret) {
-               if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
-                       dev_pm_opp_put_opp_table(genpd->opp_table);
-                       dev_pm_opp_of_remove_table(&genpd->dev);
-               }
-
-               return ret;
-       }
-
-       genpd->provider = &np->fwnode;
-       genpd->has_provider = true;
-
-       return 0;
-}
-EXPORT_SYMBOL_GPL(of_genpd_add_provider_simple);
-
-/**
- * of_genpd_add_provider_onecell() - Register a onecell PM domain provider
- * @np: Device node pointer associated with the PM domain provider.
- * @data: Pointer to the data associated with the PM domain provider.
- */
-int of_genpd_add_provider_onecell(struct device_node *np,
-                                 struct genpd_onecell_data *data)
-{
-       struct generic_pm_domain *genpd;
-       unsigned int i;
-       int ret = -EINVAL;
-
-       if (!np || !data)
-               return -EINVAL;
-
-       if (!data->xlate)
-               data->xlate = genpd_xlate_onecell;
-
-       for (i = 0; i < data->num_domains; i++) {
-               genpd = data->domains[i];
-
-               if (!genpd)
-                       continue;
-               if (!genpd_present(genpd))
-                       goto error;
-
-               genpd->dev.of_node = np;
-
-               /* Parse genpd OPP table */
-               if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
-                       ret = dev_pm_opp_of_add_table_indexed(&genpd->dev, i);
-                       if (ret) {
-                               dev_err_probe(&genpd->dev, ret,
-                                             "Failed to add OPP table for index %d\n", i);
-                               goto error;
-                       }
-
-                       /*
-                        * Save table for faster processing while setting
-                        * performance state.
-                        */
-                       genpd->opp_table = dev_pm_opp_get_opp_table(&genpd->dev);
-                       WARN_ON(IS_ERR(genpd->opp_table));
-               }
-
-               genpd->provider = &np->fwnode;
-               genpd->has_provider = true;
-       }
-
-       ret = genpd_add_provider(np, data->xlate, data);
-       if (ret < 0)
-               goto error;
-
-       return 0;
-
-error:
-       while (i--) {
-               genpd = data->domains[i];
-
-               if (!genpd)
-                       continue;
-
-               genpd->provider = NULL;
-               genpd->has_provider = false;
-
-               if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
-                       dev_pm_opp_put_opp_table(genpd->opp_table);
-                       dev_pm_opp_of_remove_table(&genpd->dev);
-               }
-       }
-
-       return ret;
-}
-EXPORT_SYMBOL_GPL(of_genpd_add_provider_onecell);
-
-/**
- * of_genpd_del_provider() - Remove a previously registered PM domain provider
- * @np: Device node pointer associated with the PM domain provider
- */
-void of_genpd_del_provider(struct device_node *np)
-{
-       struct of_genpd_provider *cp, *tmp;
-       struct generic_pm_domain *gpd;
-
-       mutex_lock(&gpd_list_lock);
-       mutex_lock(&of_genpd_mutex);
-       list_for_each_entry_safe(cp, tmp, &of_genpd_providers, link) {
-               if (cp->node == np) {
-                       /*
-                        * For each PM domain associated with the
-                        * provider, set the 'has_provider' to false
-                        * so that the PM domain can be safely removed.
-                        */
-                       list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
-                               if (gpd->provider == &np->fwnode) {
-                                       gpd->has_provider = false;
-
-                                       if (genpd_is_opp_table_fw(gpd) || !gpd->set_performance_state)
-                                               continue;
-
-                                       dev_pm_opp_put_opp_table(gpd->opp_table);
-                                       dev_pm_opp_of_remove_table(&gpd->dev);
-                               }
-                       }
-
-                       fwnode_dev_initialized(&cp->node->fwnode, false);
-                       list_del(&cp->link);
-                       of_node_put(cp->node);
-                       kfree(cp);
-                       break;
-               }
-       }
-       mutex_unlock(&of_genpd_mutex);
-       mutex_unlock(&gpd_list_lock);
-}
-EXPORT_SYMBOL_GPL(of_genpd_del_provider);
-
-/**
- * genpd_get_from_provider() - Look-up PM domain
- * @genpdspec: OF phandle args to use for look-up
- *
- * Looks for a PM domain provider under the node specified by @genpdspec and if
- * found, uses xlate function of the provider to map phandle args to a PM
- * domain.
- *
- * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
- * on failure.
- */
-static struct generic_pm_domain *genpd_get_from_provider(
-                                       struct of_phandle_args *genpdspec)
-{
-       struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
-       struct of_genpd_provider *provider;
-
-       if (!genpdspec)
-               return ERR_PTR(-EINVAL);
-
-       mutex_lock(&of_genpd_mutex);
-
-       /* Check if we have such a provider in our array */
-       list_for_each_entry(provider, &of_genpd_providers, link) {
-               if (provider->node == genpdspec->np)
-                       genpd = provider->xlate(genpdspec, provider->data);
-               if (!IS_ERR(genpd))
-                       break;
-       }
-
-       mutex_unlock(&of_genpd_mutex);
-
-       return genpd;
-}
-
-/**
- * of_genpd_add_device() - Add a device to an I/O PM domain
- * @genpdspec: OF phandle args to use for look-up PM domain
- * @dev: Device to be added.
- *
- * Looks-up an I/O PM domain based upon phandle args provided and adds
- * the device to the PM domain. Returns a negative error code on failure.
- */
-int of_genpd_add_device(struct of_phandle_args *genpdspec, struct device *dev)
-{
-       struct generic_pm_domain *genpd;
-       int ret;
-
-       if (!dev)
-               return -EINVAL;
-
-       mutex_lock(&gpd_list_lock);
-
-       genpd = genpd_get_from_provider(genpdspec);
-       if (IS_ERR(genpd)) {
-               ret = PTR_ERR(genpd);
-               goto out;
-       }
-
-       ret = genpd_add_device(genpd, dev, dev);
-
-out:
-       mutex_unlock(&gpd_list_lock);
-
-       return ret;
-}
-EXPORT_SYMBOL_GPL(of_genpd_add_device);
-
-/**
- * of_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
- * @parent_spec: OF phandle args to use for parent PM domain look-up
- * @subdomain_spec: OF phandle args to use for subdomain look-up
- *
- * Looks-up a parent PM domain and subdomain based upon phandle args
- * provided and adds the subdomain to the parent PM domain. Returns a
- * negative error code on failure.
- */
-int of_genpd_add_subdomain(struct of_phandle_args *parent_spec,
-                          struct of_phandle_args *subdomain_spec)
-{
-       struct generic_pm_domain *parent, *subdomain;
-       int ret;
-
-       mutex_lock(&gpd_list_lock);
-
-       parent = genpd_get_from_provider(parent_spec);
-       if (IS_ERR(parent)) {
-               ret = PTR_ERR(parent);
-               goto out;
-       }
-
-       subdomain = genpd_get_from_provider(subdomain_spec);
-       if (IS_ERR(subdomain)) {
-               ret = PTR_ERR(subdomain);
-               goto out;
-       }
-
-       ret = genpd_add_subdomain(parent, subdomain);
-
-out:
-       mutex_unlock(&gpd_list_lock);
-
-       return ret == -ENOENT ? -EPROBE_DEFER : ret;
-}
-EXPORT_SYMBOL_GPL(of_genpd_add_subdomain);
-
-/**
- * of_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
- * @parent_spec: OF phandle args to use for parent PM domain look-up
- * @subdomain_spec: OF phandle args to use for subdomain look-up
- *
- * Looks-up a parent PM domain and subdomain based upon phandle args
- * provided and removes the subdomain from the parent PM domain. Returns a
- * negative error code on failure.
- */
-int of_genpd_remove_subdomain(struct of_phandle_args *parent_spec,
-                             struct of_phandle_args *subdomain_spec)
-{
-       struct generic_pm_domain *parent, *subdomain;
-       int ret;
-
-       mutex_lock(&gpd_list_lock);
-
-       parent = genpd_get_from_provider(parent_spec);
-       if (IS_ERR(parent)) {
-               ret = PTR_ERR(parent);
-               goto out;
-       }
-
-       subdomain = genpd_get_from_provider(subdomain_spec);
-       if (IS_ERR(subdomain)) {
-               ret = PTR_ERR(subdomain);
-               goto out;
-       }
-
-       ret = pm_genpd_remove_subdomain(parent, subdomain);
-
-out:
-       mutex_unlock(&gpd_list_lock);
-
-       return ret;
-}
-EXPORT_SYMBOL_GPL(of_genpd_remove_subdomain);
-
-/**
- * of_genpd_remove_last - Remove the last PM domain registered for a provider
- * @np: Pointer to device node associated with provider
- *
- * Find the last PM domain that was added by a particular provider and
- * remove this PM domain from the list of PM domains. The provider is
- * identified by the 'provider' device structure that is passed. The PM
- * domain will only be removed, if the provider associated with domain
- * has been removed.
- *
- * Returns a valid pointer to struct generic_pm_domain on success or
- * ERR_PTR() on failure.
- */
-struct generic_pm_domain *of_genpd_remove_last(struct device_node *np)
-{
-       struct generic_pm_domain *gpd, *tmp, *genpd = ERR_PTR(-ENOENT);
-       int ret;
-
-       if (IS_ERR_OR_NULL(np))
-               return ERR_PTR(-EINVAL);
-
-       mutex_lock(&gpd_list_lock);
-       list_for_each_entry_safe(gpd, tmp, &gpd_list, gpd_list_node) {
-               if (gpd->provider == &np->fwnode) {
-                       ret = genpd_remove(gpd);
-                       genpd = ret ? ERR_PTR(ret) : gpd;
-                       break;
-               }
-       }
-       mutex_unlock(&gpd_list_lock);
-
-       return genpd;
-}
-EXPORT_SYMBOL_GPL(of_genpd_remove_last);
-
-static void genpd_release_dev(struct device *dev)
-{
-       of_node_put(dev->of_node);
-       kfree(dev);
-}
-
-static struct bus_type genpd_bus_type = {
-       .name           = "genpd",
-};
-
-/**
- * genpd_dev_pm_detach - Detach a device from its PM domain.
- * @dev: Device to detach.
- * @power_off: Currently not used
- *
- * Try to locate a corresponding generic PM domain, which the device was
- * attached to previously. If such is found, the device is detached from it.
- */
-static void genpd_dev_pm_detach(struct device *dev, bool power_off)
-{
-       struct generic_pm_domain *pd;
-       unsigned int i;
-       int ret = 0;
-
-       pd = dev_to_genpd(dev);
-       if (IS_ERR(pd))
-               return;
-
-       dev_dbg(dev, "removing from PM domain %s\n", pd->name);
-
-       /* Drop the default performance state */
-       if (dev_gpd_data(dev)->default_pstate) {
-               dev_pm_genpd_set_performance_state(dev, 0);
-               dev_gpd_data(dev)->default_pstate = 0;
-       }
-
-       for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
-               ret = genpd_remove_device(pd, dev);
-               if (ret != -EAGAIN)
-                       break;
-
-               mdelay(i);
-               cond_resched();
-       }
-
-       if (ret < 0) {
-               dev_err(dev, "failed to remove from PM domain %s: %d",
-                       pd->name, ret);
-               return;
-       }
-
-       /* Check if PM domain can be powered off after removing this device. */
-       genpd_queue_power_off_work(pd);
-
-       /* Unregister the device if it was created by genpd. */
-       if (dev->bus == &genpd_bus_type)
-               device_unregister(dev);
-}
-
-static void genpd_dev_pm_sync(struct device *dev)
-{
-       struct generic_pm_domain *pd;
-
-       pd = dev_to_genpd(dev);
-       if (IS_ERR(pd))
-               return;
-
-       genpd_queue_power_off_work(pd);
-}
-
-static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
-                                unsigned int index, bool power_on)
-{
-       struct of_phandle_args pd_args;
-       struct generic_pm_domain *pd;
-       int pstate;
-       int ret;
-
-       ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
-                               "#power-domain-cells", index, &pd_args);
-       if (ret < 0)
-               return ret;
-
-       mutex_lock(&gpd_list_lock);
-       pd = genpd_get_from_provider(&pd_args);
-       of_node_put(pd_args.np);
-       if (IS_ERR(pd)) {
-               mutex_unlock(&gpd_list_lock);
-               dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
-                       __func__, PTR_ERR(pd));
-               return driver_deferred_probe_check_state(base_dev);
-       }
-
-       dev_dbg(dev, "adding to PM domain %s\n", pd->name);
-
-       ret = genpd_add_device(pd, dev, base_dev);
-       mutex_unlock(&gpd_list_lock);
-
-       if (ret < 0)
-               return dev_err_probe(dev, ret, "failed to add to PM domain %s\n", pd->name);
-
-       dev->pm_domain->detach = genpd_dev_pm_detach;
-       dev->pm_domain->sync = genpd_dev_pm_sync;
-
-       /* Set the default performance state */
-       pstate = of_get_required_opp_performance_state(dev->of_node, index);
-       if (pstate < 0 && pstate != -ENODEV && pstate != -EOPNOTSUPP) {
-               ret = pstate;
-               goto err;
-       } else if (pstate > 0) {
-               ret = dev_pm_genpd_set_performance_state(dev, pstate);
-               if (ret)
-                       goto err;
-               dev_gpd_data(dev)->default_pstate = pstate;
-       }
-
-       if (power_on) {
-               genpd_lock(pd);
-               ret = genpd_power_on(pd, 0);
-               genpd_unlock(pd);
-       }
-
-       if (ret) {
-               /* Drop the default performance state */
-               if (dev_gpd_data(dev)->default_pstate) {
-                       dev_pm_genpd_set_performance_state(dev, 0);
-                       dev_gpd_data(dev)->default_pstate = 0;
-               }
-
-               genpd_remove_device(pd, dev);
-               return -EPROBE_DEFER;
-       }
-
-       return 1;
-
-err:
-       dev_err(dev, "failed to set required performance state for power-domain %s: %d\n",
-               pd->name, ret);
-       genpd_remove_device(pd, dev);
-       return ret;
-}
-
-/**
- * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
- * @dev: Device to attach.
- *
- * Parse device's OF node to find a PM domain specifier. If such is found,
- * attaches the device to retrieved pm_domain ops.
- *
- * Returns 1 on successfully attached PM domain, 0 when the device don't need a
- * PM domain or when multiple power-domains exists for it, else a negative error
- * code. Note that if a power-domain exists for the device, but it cannot be
- * found or turned on, then return -EPROBE_DEFER to ensure that the device is
- * not probed and to re-try again later.
- */
-int genpd_dev_pm_attach(struct device *dev)
-{
-       if (!dev->of_node)
-               return 0;
-
-       /*
-        * Devices with multiple PM domains must be attached separately, as we
-        * can only attach one PM domain per device.
-        */
-       if (of_count_phandle_with_args(dev->of_node, "power-domains",
-                                      "#power-domain-cells") != 1)
-               return 0;
-
-       return __genpd_dev_pm_attach(dev, dev, 0, true);
-}
-EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
-
-/**
- * genpd_dev_pm_attach_by_id - Associate a device with one of its PM domains.
- * @dev: The device used to lookup the PM domain.
- * @index: The index of the PM domain.
- *
- * Parse device's OF node to find a PM domain specifier at the provided @index.
- * If such is found, creates a virtual device and attaches it to the retrieved
- * pm_domain ops. To deal with detaching of the virtual device, the ->detach()
- * callback in the struct dev_pm_domain are assigned to genpd_dev_pm_detach().
- *
- * Returns the created virtual device if successfully attached PM domain, NULL
- * when the device don't need a PM domain, else an ERR_PTR() in case of
- * failures. If a power-domain exists for the device, but cannot be found or
- * turned on, then ERR_PTR(-EPROBE_DEFER) is returned to ensure that the device
- * is not probed and to re-try again later.
- */
-struct device *genpd_dev_pm_attach_by_id(struct device *dev,
-                                        unsigned int index)
-{
-       struct device *virt_dev;
-       int num_domains;
-       int ret;
-
-       if (!dev->of_node)
-               return NULL;
-
-       /* Verify that the index is within a valid range. */
-       num_domains = of_count_phandle_with_args(dev->of_node, "power-domains",
-                                                "#power-domain-cells");
-       if (index >= num_domains)
-               return NULL;
-
-       /* Allocate and register device on the genpd bus. */
-       virt_dev = kzalloc(sizeof(*virt_dev), GFP_KERNEL);
-       if (!virt_dev)
-               return ERR_PTR(-ENOMEM);
-
-       dev_set_name(virt_dev, "genpd:%u:%s", index, dev_name(dev));
-       virt_dev->bus = &genpd_bus_type;
-       virt_dev->release = genpd_release_dev;
-       virt_dev->of_node = of_node_get(dev->of_node);
-
-       ret = device_register(virt_dev);
-       if (ret) {
-               put_device(virt_dev);
-               return ERR_PTR(ret);
-       }
-
-       /* Try to attach the device to the PM domain at the specified index. */
-       ret = __genpd_dev_pm_attach(virt_dev, dev, index, false);
-       if (ret < 1) {
-               device_unregister(virt_dev);
-               return ret ? ERR_PTR(ret) : NULL;
-       }
-
-       pm_runtime_enable(virt_dev);
-       genpd_queue_power_off_work(dev_to_genpd(virt_dev));
-
-       return virt_dev;
-}
-EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id);
-
-/**
- * genpd_dev_pm_attach_by_name - Associate a device with one of its PM domains.
- * @dev: The device used to lookup the PM domain.
- * @name: The name of the PM domain.
- *
- * Parse device's OF node to find a PM domain specifier using the
- * power-domain-names DT property. For further description see
- * genpd_dev_pm_attach_by_id().
- */
-struct device *genpd_dev_pm_attach_by_name(struct device *dev, const char *name)
-{
-       int index;
-
-       if (!dev->of_node)
-               return NULL;
-
-       index = of_property_match_string(dev->of_node, "power-domain-names",
-                                        name);
-       if (index < 0)
-               return NULL;
-
-       return genpd_dev_pm_attach_by_id(dev, index);
-}
-
-static const struct of_device_id idle_state_match[] = {
-       { .compatible = "domain-idle-state", },
-       { }
-};
-
-static int genpd_parse_state(struct genpd_power_state *genpd_state,
-                                   struct device_node *state_node)
-{
-       int err;
-       u32 residency;
-       u32 entry_latency, exit_latency;
-
-       err = of_property_read_u32(state_node, "entry-latency-us",
-                                               &entry_latency);
-       if (err) {
-               pr_debug(" * %pOF missing entry-latency-us property\n",
-                        state_node);
-               return -EINVAL;
-       }
-
-       err = of_property_read_u32(state_node, "exit-latency-us",
-                                               &exit_latency);
-       if (err) {
-               pr_debug(" * %pOF missing exit-latency-us property\n",
-                        state_node);
-               return -EINVAL;
-       }
-
-       err = of_property_read_u32(state_node, "min-residency-us", &residency);
-       if (!err)
-               genpd_state->residency_ns = 1000LL * residency;
-
-       genpd_state->power_on_latency_ns = 1000LL * exit_latency;
-       genpd_state->power_off_latency_ns = 1000LL * entry_latency;
-       genpd_state->fwnode = &state_node->fwnode;
-
-       return 0;
-}
-
-static int genpd_iterate_idle_states(struct device_node *dn,
-                                    struct genpd_power_state *states)
-{
-       int ret;
-       struct of_phandle_iterator it;
-       struct device_node *np;
-       int i = 0;
-
-       ret = of_count_phandle_with_args(dn, "domain-idle-states", NULL);
-       if (ret <= 0)
-               return ret == -ENOENT ? 0 : ret;
-
-       /* Loop over the phandles until all the requested entry is found */
-       of_for_each_phandle(&it, ret, dn, "domain-idle-states", NULL, 0) {
-               np = it.node;
-               if (!of_match_node(idle_state_match, np))
-                       continue;
-
-               if (!of_device_is_available(np))
-                       continue;
-
-               if (states) {
-                       ret = genpd_parse_state(&states[i], np);
-                       if (ret) {
-                               pr_err("Parsing idle state node %pOF failed with err %d\n",
-                                      np, ret);
-                               of_node_put(np);
-                               return ret;
-                       }
-               }
-               i++;
-       }
-
-       return i;
-}
-
-/**
- * of_genpd_parse_idle_states: Return array of idle states for the genpd.
- *
- * @dn: The genpd device node
- * @states: The pointer to which the state array will be saved.
- * @n: The count of elements in the array returned from this function.
- *
- * Returns the device states parsed from the OF node. The memory for the states
- * is allocated by this function and is the responsibility of the caller to
- * free the memory after use. If any or zero compatible domain idle states is
- * found it returns 0 and in case of errors, a negative error code is returned.
- */
-int of_genpd_parse_idle_states(struct device_node *dn,
-                       struct genpd_power_state **states, int *n)
-{
-       struct genpd_power_state *st;
-       int ret;
-
-       ret = genpd_iterate_idle_states(dn, NULL);
-       if (ret < 0)
-               return ret;
-
-       if (!ret) {
-               *states = NULL;
-               *n = 0;
-               return 0;
-       }
-
-       st = kcalloc(ret, sizeof(*st), GFP_KERNEL);
-       if (!st)
-               return -ENOMEM;
-
-       ret = genpd_iterate_idle_states(dn, st);
-       if (ret <= 0) {
-               kfree(st);
-               return ret < 0 ? ret : -EINVAL;
-       }
-
-       *states = st;
-       *n = ret;
-
-       return 0;
-}
-EXPORT_SYMBOL_GPL(of_genpd_parse_idle_states);
-
-static int __init genpd_bus_init(void)
-{
-       return bus_register(&genpd_bus_type);
-}
-core_initcall(genpd_bus_init);
-
-#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
-
-
-/***        debugfs support        ***/
-
-#ifdef CONFIG_DEBUG_FS
-/*
- * TODO: This function is a slightly modified version of rtpm_status_show
- * from sysfs.c, so generalize it.
- */
-static void rtpm_status_str(struct seq_file *s, struct device *dev)
-{
-       static const char * const status_lookup[] = {
-               [RPM_ACTIVE] = "active",
-               [RPM_RESUMING] = "resuming",
-               [RPM_SUSPENDED] = "suspended",
-               [RPM_SUSPENDING] = "suspending"
-       };
-       const char *p = "";
-
-       if (dev->power.runtime_error)
-               p = "error";
-       else if (dev->power.disable_depth)
-               p = "unsupported";
-       else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup))
-               p = status_lookup[dev->power.runtime_status];
-       else
-               WARN_ON(1);
-
-       seq_printf(s, "%-25s  ", p);
-}
-
-static void perf_status_str(struct seq_file *s, struct device *dev)
-{
-       struct generic_pm_domain_data *gpd_data;
-
-       gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
-       seq_put_decimal_ull(s, "", gpd_data->performance_state);
-}
-
-static int genpd_summary_one(struct seq_file *s,
-                       struct generic_pm_domain *genpd)
-{
-       static const char * const status_lookup[] = {
-               [GENPD_STATE_ON] = "on",
-               [GENPD_STATE_OFF] = "off"
-       };
-       struct pm_domain_data *pm_data;
-       const char *kobj_path;
-       struct gpd_link *link;
-       char state[16];
-       int ret;
-
-       ret = genpd_lock_interruptible(genpd);
-       if (ret)
-               return -ERESTARTSYS;
-
-       if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
-               goto exit;
-       if (!genpd_status_on(genpd))
-               snprintf(state, sizeof(state), "%s-%u",
-                        status_lookup[genpd->status], genpd->state_idx);
-       else
-               snprintf(state, sizeof(state), "%s",
-                        status_lookup[genpd->status]);
-       seq_printf(s, "%-30s  %-50s %u", genpd->name, state, genpd->performance_state);
-
-       /*
-        * Modifications on the list require holding locks on both
-        * parent and child, so we are safe.
-        * Also genpd->name is immutable.
-        */
-       list_for_each_entry(link, &genpd->parent_links, parent_node) {
-               if (list_is_first(&link->parent_node, &genpd->parent_links))
-                       seq_printf(s, "\n%48s", " ");
-               seq_printf(s, "%s", link->child->name);
-               if (!list_is_last(&link->parent_node, &genpd->parent_links))
-                       seq_puts(s, ", ");
-       }
-
-       list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
-               kobj_path = kobject_get_path(&pm_data->dev->kobj,
-                               genpd_is_irq_safe(genpd) ?
-                               GFP_ATOMIC : GFP_KERNEL);
-               if (kobj_path == NULL)
-                       continue;
-
-               seq_printf(s, "\n    %-50s  ", kobj_path);
-               rtpm_status_str(s, pm_data->dev);
-               perf_status_str(s, pm_data->dev);
-               kfree(kobj_path);
-       }
-
-       seq_puts(s, "\n");
-exit:
-       genpd_unlock(genpd);
-
-       return 0;
-}
-
-static int summary_show(struct seq_file *s, void *data)
-{
-       struct generic_pm_domain *genpd;
-       int ret = 0;
-
-       seq_puts(s, "domain                          status          children                           performance\n");
-       seq_puts(s, "    /device                                             runtime status\n");
-       seq_puts(s, "----------------------------------------------------------------------------------------------\n");
-
-       ret = mutex_lock_interruptible(&gpd_list_lock);
-       if (ret)
-               return -ERESTARTSYS;
-
-       list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
-               ret = genpd_summary_one(s, genpd);
-               if (ret)
-                       break;
-       }
-       mutex_unlock(&gpd_list_lock);
-
-       return ret;
-}
-
-static int status_show(struct seq_file *s, void *data)
-{
-       static const char * const status_lookup[] = {
-               [GENPD_STATE_ON] = "on",
-               [GENPD_STATE_OFF] = "off"
-       };
-
-       struct generic_pm_domain *genpd = s->private;
-       int ret = 0;
-
-       ret = genpd_lock_interruptible(genpd);
-       if (ret)
-               return -ERESTARTSYS;
-
-       if (WARN_ON_ONCE(genpd->status >= ARRAY_SIZE(status_lookup)))
-               goto exit;
-
-       if (genpd->status == GENPD_STATE_OFF)
-               seq_printf(s, "%s-%u\n", status_lookup[genpd->status],
-                       genpd->state_idx);
-       else
-               seq_printf(s, "%s\n", status_lookup[genpd->status]);
-exit:
-       genpd_unlock(genpd);
-       return ret;
-}
-
-static int sub_domains_show(struct seq_file *s, void *data)
-{
-       struct generic_pm_domain *genpd = s->private;
-       struct gpd_link *link;
-       int ret = 0;
-
-       ret = genpd_lock_interruptible(genpd);
-       if (ret)
-               return -ERESTARTSYS;
-
-       list_for_each_entry(link, &genpd->parent_links, parent_node)
-               seq_printf(s, "%s\n", link->child->name);
-
-       genpd_unlock(genpd);
-       return ret;
-}
-
-static int idle_states_show(struct seq_file *s, void *data)
-{
-       struct generic_pm_domain *genpd = s->private;
-       u64 now, delta, idle_time = 0;
-       unsigned int i;
-       int ret = 0;
-
-       ret = genpd_lock_interruptible(genpd);
-       if (ret)
-               return -ERESTARTSYS;
-
-       seq_puts(s, "State          Time Spent(ms) Usage          Rejected\n");
-
-       for (i = 0; i < genpd->state_count; i++) {
-               idle_time += genpd->states[i].idle_time;
-
-               if (genpd->status == GENPD_STATE_OFF && genpd->state_idx == i) {
-                       now = ktime_get_mono_fast_ns();
-                       if (now > genpd->accounting_time) {
-                               delta = now - genpd->accounting_time;
-                               idle_time += delta;
-                       }
-               }
-
-               do_div(idle_time, NSEC_PER_MSEC);
-               seq_printf(s, "S%-13i %-14llu %-14llu %llu\n", i, idle_time,
-                          genpd->states[i].usage, genpd->states[i].rejected);
-       }
-
-       genpd_unlock(genpd);
-       return ret;
-}
-
-static int active_time_show(struct seq_file *s, void *data)
-{
-       struct generic_pm_domain *genpd = s->private;
-       u64 now, on_time, delta = 0;
-       int ret = 0;
-
-       ret = genpd_lock_interruptible(genpd);
-       if (ret)
-               return -ERESTARTSYS;
-
-       if (genpd->status == GENPD_STATE_ON) {
-               now = ktime_get_mono_fast_ns();
-               if (now > genpd->accounting_time)
-                       delta = now - genpd->accounting_time;
-       }
-
-       on_time = genpd->on_time + delta;
-       do_div(on_time, NSEC_PER_MSEC);
-       seq_printf(s, "%llu ms\n", on_time);
-
-       genpd_unlock(genpd);
-       return ret;
-}
-
-static int total_idle_time_show(struct seq_file *s, void *data)
-{
-       struct generic_pm_domain *genpd = s->private;
-       u64 now, delta, total = 0;
-       unsigned int i;
-       int ret = 0;
-
-       ret = genpd_lock_interruptible(genpd);
-       if (ret)
-               return -ERESTARTSYS;
-
-       for (i = 0; i < genpd->state_count; i++) {
-               total += genpd->states[i].idle_time;
-
-               if (genpd->status == GENPD_STATE_OFF && genpd->state_idx == i) {
-                       now = ktime_get_mono_fast_ns();
-                       if (now > genpd->accounting_time) {
-                               delta = now - genpd->accounting_time;
-                               total += delta;
-                       }
-               }
-       }
-
-       do_div(total, NSEC_PER_MSEC);
-       seq_printf(s, "%llu ms\n", total);
-
-       genpd_unlock(genpd);
-       return ret;
-}
-
-
-static int devices_show(struct seq_file *s, void *data)
-{
-       struct generic_pm_domain *genpd = s->private;
-       struct pm_domain_data *pm_data;
-       const char *kobj_path;
-       int ret = 0;
-
-       ret = genpd_lock_interruptible(genpd);
-       if (ret)
-               return -ERESTARTSYS;
-
-       list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
-               kobj_path = kobject_get_path(&pm_data->dev->kobj,
-                               genpd_is_irq_safe(genpd) ?
-                               GFP_ATOMIC : GFP_KERNEL);
-               if (kobj_path == NULL)
-                       continue;
-
-               seq_printf(s, "%s\n", kobj_path);
-               kfree(kobj_path);
-       }
-
-       genpd_unlock(genpd);
-       return ret;
-}
-
-static int perf_state_show(struct seq_file *s, void *data)
-{
-       struct generic_pm_domain *genpd = s->private;
-
-       if (genpd_lock_interruptible(genpd))
-               return -ERESTARTSYS;
-
-       seq_printf(s, "%u\n", genpd->performance_state);
-
-       genpd_unlock(genpd);
-       return 0;
-}
-
-DEFINE_SHOW_ATTRIBUTE(summary);
-DEFINE_SHOW_ATTRIBUTE(status);
-DEFINE_SHOW_ATTRIBUTE(sub_domains);
-DEFINE_SHOW_ATTRIBUTE(idle_states);
-DEFINE_SHOW_ATTRIBUTE(active_time);
-DEFINE_SHOW_ATTRIBUTE(total_idle_time);
-DEFINE_SHOW_ATTRIBUTE(devices);
-DEFINE_SHOW_ATTRIBUTE(perf_state);
-
-static void genpd_debug_add(struct generic_pm_domain *genpd)
-{
-       struct dentry *d;
-
-       if (!genpd_debugfs_dir)
-               return;
-
-       d = debugfs_create_dir(genpd->name, genpd_debugfs_dir);
-
-       debugfs_create_file("current_state", 0444,
-                           d, genpd, &status_fops);
-       debugfs_create_file("sub_domains", 0444,
-                           d, genpd, &sub_domains_fops);
-       debugfs_create_file("idle_states", 0444,
-                           d, genpd, &idle_states_fops);
-       debugfs_create_file("active_time", 0444,
-                           d, genpd, &active_time_fops);
-       debugfs_create_file("total_idle_time", 0444,
-                           d, genpd, &total_idle_time_fops);
-       debugfs_create_file("devices", 0444,
-                           d, genpd, &devices_fops);
-       if (genpd->set_performance_state)
-               debugfs_create_file("perf_state", 0444,
-                                   d, genpd, &perf_state_fops);
-}
-
-static int __init genpd_debug_init(void)
-{
-       struct generic_pm_domain *genpd;
-
-       genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
-
-       debugfs_create_file("pm_genpd_summary", S_IRUGO, genpd_debugfs_dir,
-                           NULL, &summary_fops);
-
-       list_for_each_entry(genpd, &gpd_list, gpd_list_node)
-               genpd_debug_add(genpd);
-
-       return 0;
-}
-late_initcall(genpd_debug_init);
-
-static void __exit genpd_debug_exit(void)
-{
-       debugfs_remove_recursive(genpd_debugfs_dir);
-}
-__exitcall(genpd_debug_exit);
-#endif /* CONFIG_DEBUG_FS */
diff --git a/drivers/base/power/domain_governor.c b/drivers/base/power/domain_governor.c
deleted file mode 100644 (file)
index d1a10ee..0000000
+++ /dev/null
@@ -1,418 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * drivers/base/power/domain_governor.c - Governors for device PM domains.
- *
- * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
- */
-#include <linux/kernel.h>
-#include <linux/pm_domain.h>
-#include <linux/pm_qos.h>
-#include <linux/hrtimer.h>
-#include <linux/cpuidle.h>
-#include <linux/cpumask.h>
-#include <linux/ktime.h>
-
-static int dev_update_qos_constraint(struct device *dev, void *data)
-{
-       s64 *constraint_ns_p = data;
-       s64 constraint_ns;
-
-       if (dev->power.subsys_data && dev->power.subsys_data->domain_data) {
-               struct gpd_timing_data *td = dev_gpd_data(dev)->td;
-
-               /*
-                * Only take suspend-time QoS constraints of devices into
-                * account, because constraints updated after the device has
-                * been suspended are not guaranteed to be taken into account
-                * anyway.  In order for them to take effect, the device has to
-                * be resumed and suspended again.
-                */
-               constraint_ns = td ? td->effective_constraint_ns :
-                               PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
-       } else {
-               /*
-                * The child is not in a domain and there's no info on its
-                * suspend/resume latencies, so assume them to be negligible and
-                * take its current PM QoS constraint (that's the only thing
-                * known at this point anyway).
-                */
-               constraint_ns = dev_pm_qos_read_value(dev, DEV_PM_QOS_RESUME_LATENCY);
-               constraint_ns *= NSEC_PER_USEC;
-       }
-
-       if (constraint_ns < *constraint_ns_p)
-               *constraint_ns_p = constraint_ns;
-
-       return 0;
-}
-
-/**
- * default_suspend_ok - Default PM domain governor routine to suspend devices.
- * @dev: Device to check.
- *
- * Returns: true if OK to suspend, false if not OK to suspend
- */
-static bool default_suspend_ok(struct device *dev)
-{
-       struct gpd_timing_data *td = dev_gpd_data(dev)->td;
-       unsigned long flags;
-       s64 constraint_ns;
-
-       dev_dbg(dev, "%s()\n", __func__);
-
-       spin_lock_irqsave(&dev->power.lock, flags);
-
-       if (!td->constraint_changed) {
-               bool ret = td->cached_suspend_ok;
-
-               spin_unlock_irqrestore(&dev->power.lock, flags);
-               return ret;
-       }
-       td->constraint_changed = false;
-       td->cached_suspend_ok = false;
-       td->effective_constraint_ns = 0;
-       constraint_ns = __dev_pm_qos_resume_latency(dev);
-
-       spin_unlock_irqrestore(&dev->power.lock, flags);
-
-       if (constraint_ns == 0)
-               return false;
-
-       constraint_ns *= NSEC_PER_USEC;
-       /*
-        * We can walk the children without any additional locking, because
-        * they all have been suspended at this point and their
-        * effective_constraint_ns fields won't be modified in parallel with us.
-        */
-       if (!dev->power.ignore_children)
-               device_for_each_child(dev, &constraint_ns,
-                                     dev_update_qos_constraint);
-
-       if (constraint_ns == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS) {
-               /* "No restriction", so the device is allowed to suspend. */
-               td->effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
-               td->cached_suspend_ok = true;
-       } else if (constraint_ns == 0) {
-               /*
-                * This triggers if one of the children that don't belong to a
-                * domain has a zero PM QoS constraint and it's better not to
-                * suspend then.  effective_constraint_ns is zero already and
-                * cached_suspend_ok is false, so bail out.
-                */
-               return false;
-       } else {
-               constraint_ns -= td->suspend_latency_ns +
-                               td->resume_latency_ns;
-               /*
-                * effective_constraint_ns is zero already and cached_suspend_ok
-                * is false, so if the computed value is not positive, return
-                * right away.
-                */
-               if (constraint_ns <= 0)
-                       return false;
-
-               td->effective_constraint_ns = constraint_ns;
-               td->cached_suspend_ok = true;
-       }
-
-       /*
-        * The children have been suspended already, so we don't need to take
-        * their suspend latencies into account here.
-        */
-       return td->cached_suspend_ok;
-}
-
-static void update_domain_next_wakeup(struct generic_pm_domain *genpd, ktime_t now)
-{
-       ktime_t domain_wakeup = KTIME_MAX;
-       ktime_t next_wakeup;
-       struct pm_domain_data *pdd;
-       struct gpd_link *link;
-
-       if (!(genpd->flags & GENPD_FLAG_MIN_RESIDENCY))
-               return;
-
-       /*
-        * Devices that have a predictable wakeup pattern, may specify
-        * their next wakeup. Let's find the next wakeup from all the
-        * devices attached to this domain and from all the sub-domains.
-        * It is possible that component's a next wakeup may have become
-        * stale when we read that here. We will ignore to ensure the domain
-        * is able to enter its optimal idle state.
-        */
-       list_for_each_entry(pdd, &genpd->dev_list, list_node) {
-               next_wakeup = to_gpd_data(pdd)->td->next_wakeup;
-               if (next_wakeup != KTIME_MAX && !ktime_before(next_wakeup, now))
-                       if (ktime_before(next_wakeup, domain_wakeup))
-                               domain_wakeup = next_wakeup;
-       }
-
-       list_for_each_entry(link, &genpd->parent_links, parent_node) {
-               struct genpd_governor_data *cgd = link->child->gd;
-
-               next_wakeup = cgd ? cgd->next_wakeup : KTIME_MAX;
-               if (next_wakeup != KTIME_MAX && !ktime_before(next_wakeup, now))
-                       if (ktime_before(next_wakeup, domain_wakeup))
-                               domain_wakeup = next_wakeup;
-       }
-
-       genpd->gd->next_wakeup = domain_wakeup;
-}
-
-static bool next_wakeup_allows_state(struct generic_pm_domain *genpd,
-                                    unsigned int state, ktime_t now)
-{
-       ktime_t domain_wakeup = genpd->gd->next_wakeup;
-       s64 idle_time_ns, min_sleep_ns;
-
-       min_sleep_ns = genpd->states[state].power_off_latency_ns +
-                      genpd->states[state].residency_ns;
-
-       idle_time_ns = ktime_to_ns(ktime_sub(domain_wakeup, now));
-
-       return idle_time_ns >= min_sleep_ns;
-}
-
-static bool __default_power_down_ok(struct dev_pm_domain *pd,
-                                    unsigned int state)
-{
-       struct generic_pm_domain *genpd = pd_to_genpd(pd);
-       struct gpd_link *link;
-       struct pm_domain_data *pdd;
-       s64 min_off_time_ns;
-       s64 off_on_time_ns;
-
-       off_on_time_ns = genpd->states[state].power_off_latency_ns +
-               genpd->states[state].power_on_latency_ns;
-
-       min_off_time_ns = -1;
-       /*
-        * Check if subdomains can be off for enough time.
-        *
-        * All subdomains have been powered off already at this point.
-        */
-       list_for_each_entry(link, &genpd->parent_links, parent_node) {
-               struct genpd_governor_data *cgd = link->child->gd;
-
-               s64 sd_max_off_ns = cgd ? cgd->max_off_time_ns : -1;
-
-               if (sd_max_off_ns < 0)
-                       continue;
-
-               /*
-                * Check if the subdomain is allowed to be off long enough for
-                * the current domain to turn off and on (that's how much time
-                * it will have to wait worst case).
-                */
-               if (sd_max_off_ns <= off_on_time_ns)
-                       return false;
-
-               if (min_off_time_ns > sd_max_off_ns || min_off_time_ns < 0)
-                       min_off_time_ns = sd_max_off_ns;
-       }
-
-       /*
-        * Check if the devices in the domain can be off enough time.
-        */
-       list_for_each_entry(pdd, &genpd->dev_list, list_node) {
-               struct gpd_timing_data *td;
-               s64 constraint_ns;
-
-               /*
-                * Check if the device is allowed to be off long enough for the
-                * domain to turn off and on (that's how much time it will
-                * have to wait worst case).
-                */
-               td = to_gpd_data(pdd)->td;
-               constraint_ns = td->effective_constraint_ns;
-               /*
-                * Zero means "no suspend at all" and this runs only when all
-                * devices in the domain are suspended, so it must be positive.
-                */
-               if (constraint_ns == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS)
-                       continue;
-
-               if (constraint_ns <= off_on_time_ns)
-                       return false;
-
-               if (min_off_time_ns > constraint_ns || min_off_time_ns < 0)
-                       min_off_time_ns = constraint_ns;
-       }
-
-       /*
-        * If the computed minimum device off time is negative, there are no
-        * latency constraints, so the domain can spend arbitrary time in the
-        * "off" state.
-        */
-       if (min_off_time_ns < 0)
-               return true;
-
-       /*
-        * The difference between the computed minimum subdomain or device off
-        * time and the time needed to turn the domain on is the maximum
-        * theoretical time this domain can spend in the "off" state.
-        */
-       genpd->gd->max_off_time_ns = min_off_time_ns -
-               genpd->states[state].power_on_latency_ns;
-       return true;
-}
-
-/**
- * _default_power_down_ok - Default generic PM domain power off governor routine.
- * @pd: PM domain to check.
- * @now: current ktime.
- *
- * This routine must be executed under the PM domain's lock.
- *
- * Returns: true if OK to power down, false if not OK to power down
- */
-static bool _default_power_down_ok(struct dev_pm_domain *pd, ktime_t now)
-{
-       struct generic_pm_domain *genpd = pd_to_genpd(pd);
-       struct genpd_governor_data *gd = genpd->gd;
-       int state_idx = genpd->state_count - 1;
-       struct gpd_link *link;
-
-       /*
-        * Find the next wakeup from devices that can determine their own wakeup
-        * to find when the domain would wakeup and do it for every device down
-        * the hierarchy. It is not worth while to sleep if the state's residency
-        * cannot be met.
-        */
-       update_domain_next_wakeup(genpd, now);
-       if ((genpd->flags & GENPD_FLAG_MIN_RESIDENCY) && (gd->next_wakeup != KTIME_MAX)) {
-               /* Let's find out the deepest domain idle state, the devices prefer */
-               while (state_idx >= 0) {
-                       if (next_wakeup_allows_state(genpd, state_idx, now)) {
-                               gd->max_off_time_changed = true;
-                               break;
-                       }
-                       state_idx--;
-               }
-
-               if (state_idx < 0) {
-                       state_idx = 0;
-                       gd->cached_power_down_ok = false;
-                       goto done;
-               }
-       }
-
-       if (!gd->max_off_time_changed) {
-               genpd->state_idx = gd->cached_power_down_state_idx;
-               return gd->cached_power_down_ok;
-       }
-
-       /*
-        * We have to invalidate the cached results for the parents, so
-        * use the observation that default_power_down_ok() is not
-        * going to be called for any parent until this instance
-        * returns.
-        */
-       list_for_each_entry(link, &genpd->child_links, child_node) {
-               struct genpd_governor_data *pgd = link->parent->gd;
-
-               if (pgd)
-                       pgd->max_off_time_changed = true;
-       }
-
-       gd->max_off_time_ns = -1;
-       gd->max_off_time_changed = false;
-       gd->cached_power_down_ok = true;
-
-       /*
-        * Find a state to power down to, starting from the state
-        * determined by the next wakeup.
-        */
-       while (!__default_power_down_ok(pd, state_idx)) {
-               if (state_idx == 0) {
-                       gd->cached_power_down_ok = false;
-                       break;
-               }
-               state_idx--;
-       }
-
-done:
-       genpd->state_idx = state_idx;
-       gd->cached_power_down_state_idx = genpd->state_idx;
-       return gd->cached_power_down_ok;
-}
-
-static bool default_power_down_ok(struct dev_pm_domain *pd)
-{
-       return _default_power_down_ok(pd, ktime_get());
-}
-
-#ifdef CONFIG_CPU_IDLE
-static bool cpu_power_down_ok(struct dev_pm_domain *pd)
-{
-       struct generic_pm_domain *genpd = pd_to_genpd(pd);
-       struct cpuidle_device *dev;
-       ktime_t domain_wakeup, next_hrtimer;
-       ktime_t now = ktime_get();
-       s64 idle_duration_ns;
-       int cpu, i;
-
-       /* Validate dev PM QoS constraints. */
-       if (!_default_power_down_ok(pd, now))
-               return false;
-
-       if (!(genpd->flags & GENPD_FLAG_CPU_DOMAIN))
-               return true;
-
-       /*
-        * Find the next wakeup for any of the online CPUs within the PM domain
-        * and its subdomains. Note, we only need the genpd->cpus, as it already
-        * contains a mask of all CPUs from subdomains.
-        */
-       domain_wakeup = ktime_set(KTIME_SEC_MAX, 0);
-       for_each_cpu_and(cpu, genpd->cpus, cpu_online_mask) {
-               dev = per_cpu(cpuidle_devices, cpu);
-               if (dev) {
-                       next_hrtimer = READ_ONCE(dev->next_hrtimer);
-                       if (ktime_before(next_hrtimer, domain_wakeup))
-                               domain_wakeup = next_hrtimer;
-               }
-       }
-
-       /* The minimum idle duration is from now - until the next wakeup. */
-       idle_duration_ns = ktime_to_ns(ktime_sub(domain_wakeup, now));
-       if (idle_duration_ns <= 0)
-               return false;
-
-       /* Store the next domain_wakeup to allow consumers to use it. */
-       genpd->gd->next_hrtimer = domain_wakeup;
-
-       /*
-        * Find the deepest idle state that has its residency value satisfied
-        * and by also taking into account the power off latency for the state.
-        * Start at the state picked by the dev PM QoS constraint validation.
-        */
-       i = genpd->state_idx;
-       do {
-               if (idle_duration_ns >= (genpd->states[i].residency_ns +
-                   genpd->states[i].power_off_latency_ns)) {
-                       genpd->state_idx = i;
-                       return true;
-               }
-       } while (--i >= 0);
-
-       return false;
-}
-
-struct dev_power_governor pm_domain_cpu_gov = {
-       .suspend_ok = default_suspend_ok,
-       .power_down_ok = cpu_power_down_ok,
-};
-#endif
-
-struct dev_power_governor simple_qos_governor = {
-       .suspend_ok = default_suspend_ok,
-       .power_down_ok = default_power_down_ok,
-};
-
-/*
- * pm_domain_always_on_gov - A governor implementing an always-on policy
- */
-struct dev_power_governor pm_domain_always_on_gov = {
-       .suspend_ok = default_suspend_ok,
-};
index f0326b27b30b2f2e5a0978d35a49353c9d362e15..a68ece2f4c68a28bfc5495a532336b369e8a4ff3 100644 (file)
@@ -16,3 +16,4 @@ obj-y                                 += sunxi/
 obj-y                                  += tegra/
 obj-y                                  += ti/
 obj-y                                  += xilinx/
+obj-y                                  += core.o governor.o
diff --git a/drivers/pmdomain/core.c b/drivers/pmdomain/core.c
new file mode 100644 (file)
index 0000000..9ee1bf2
--- /dev/null
@@ -0,0 +1,3399 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * drivers/base/power/domain.c - Common code related to device power domains.
+ *
+ * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
+ */
+#define pr_fmt(fmt) "PM: " fmt
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/pm_runtime.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_qos.h>
+#include <linux/pm_clock.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/sched.h>
+#include <linux/suspend.h>
+#include <linux/export.h>
+#include <linux/cpu.h>
+#include <linux/debugfs.h>
+
+#define GENPD_RETRY_MAX_MS     250             /* Approximate */
+
+#define GENPD_DEV_CALLBACK(genpd, type, callback, dev)         \
+({                                                             \
+       type (*__routine)(struct device *__d);                  \
+       type __ret = (type)0;                                   \
+                                                               \
+       __routine = genpd->dev_ops.callback;                    \
+       if (__routine) {                                        \
+               __ret = __routine(dev);                         \
+       }                                                       \
+       __ret;                                                  \
+})
+
+static LIST_HEAD(gpd_list);
+static DEFINE_MUTEX(gpd_list_lock);
+
+struct genpd_lock_ops {
+       void (*lock)(struct generic_pm_domain *genpd);
+       void (*lock_nested)(struct generic_pm_domain *genpd, int depth);
+       int (*lock_interruptible)(struct generic_pm_domain *genpd);
+       void (*unlock)(struct generic_pm_domain *genpd);
+};
+
+static void genpd_lock_mtx(struct generic_pm_domain *genpd)
+{
+       mutex_lock(&genpd->mlock);
+}
+
+static void genpd_lock_nested_mtx(struct generic_pm_domain *genpd,
+                                       int depth)
+{
+       mutex_lock_nested(&genpd->mlock, depth);
+}
+
+static int genpd_lock_interruptible_mtx(struct generic_pm_domain *genpd)
+{
+       return mutex_lock_interruptible(&genpd->mlock);
+}
+
+static void genpd_unlock_mtx(struct generic_pm_domain *genpd)
+{
+       return mutex_unlock(&genpd->mlock);
+}
+
+static const struct genpd_lock_ops genpd_mtx_ops = {
+       .lock = genpd_lock_mtx,
+       .lock_nested = genpd_lock_nested_mtx,
+       .lock_interruptible = genpd_lock_interruptible_mtx,
+       .unlock = genpd_unlock_mtx,
+};
+
+static void genpd_lock_spin(struct generic_pm_domain *genpd)
+       __acquires(&genpd->slock)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&genpd->slock, flags);
+       genpd->lock_flags = flags;
+}
+
+static void genpd_lock_nested_spin(struct generic_pm_domain *genpd,
+                                       int depth)
+       __acquires(&genpd->slock)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave_nested(&genpd->slock, flags, depth);
+       genpd->lock_flags = flags;
+}
+
+static int genpd_lock_interruptible_spin(struct generic_pm_domain *genpd)
+       __acquires(&genpd->slock)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&genpd->slock, flags);
+       genpd->lock_flags = flags;
+       return 0;
+}
+
+static void genpd_unlock_spin(struct generic_pm_domain *genpd)
+       __releases(&genpd->slock)
+{
+       spin_unlock_irqrestore(&genpd->slock, genpd->lock_flags);
+}
+
+static const struct genpd_lock_ops genpd_spin_ops = {
+       .lock = genpd_lock_spin,
+       .lock_nested = genpd_lock_nested_spin,
+       .lock_interruptible = genpd_lock_interruptible_spin,
+       .unlock = genpd_unlock_spin,
+};
+
+#define genpd_lock(p)                  p->lock_ops->lock(p)
+#define genpd_lock_nested(p, d)                p->lock_ops->lock_nested(p, d)
+#define genpd_lock_interruptible(p)    p->lock_ops->lock_interruptible(p)
+#define genpd_unlock(p)                        p->lock_ops->unlock(p)
+
+#define genpd_status_on(genpd)         (genpd->status == GENPD_STATE_ON)
+#define genpd_is_irq_safe(genpd)       (genpd->flags & GENPD_FLAG_IRQ_SAFE)
+#define genpd_is_always_on(genpd)      (genpd->flags & GENPD_FLAG_ALWAYS_ON)
+#define genpd_is_active_wakeup(genpd)  (genpd->flags & GENPD_FLAG_ACTIVE_WAKEUP)
+#define genpd_is_cpu_domain(genpd)     (genpd->flags & GENPD_FLAG_CPU_DOMAIN)
+#define genpd_is_rpm_always_on(genpd)  (genpd->flags & GENPD_FLAG_RPM_ALWAYS_ON)
+#define genpd_is_opp_table_fw(genpd)   (genpd->flags & GENPD_FLAG_OPP_TABLE_FW)
+
+static inline bool irq_safe_dev_in_sleep_domain(struct device *dev,
+               const struct generic_pm_domain *genpd)
+{
+       bool ret;
+
+       ret = pm_runtime_is_irq_safe(dev) && !genpd_is_irq_safe(genpd);
+
+       /*
+        * Warn once if an IRQ safe device is attached to a domain, which
+        * callbacks are allowed to sleep. This indicates a suboptimal
+        * configuration for PM, but it doesn't matter for an always on domain.
+        */
+       if (genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd))
+               return ret;
+
+       if (ret)
+               dev_warn_once(dev, "PM domain %s will not be powered off\n",
+                               genpd->name);
+
+       return ret;
+}
+
+static int genpd_runtime_suspend(struct device *dev);
+
+/*
+ * Get the generic PM domain for a particular struct device.
+ * This validates the struct device pointer, the PM domain pointer,
+ * and checks that the PM domain pointer is a real generic PM domain.
+ * Any failure results in NULL being returned.
+ */
+static struct generic_pm_domain *dev_to_genpd_safe(struct device *dev)
+{
+       if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain))
+               return NULL;
+
+       /* A genpd's always have its ->runtime_suspend() callback assigned. */
+       if (dev->pm_domain->ops.runtime_suspend == genpd_runtime_suspend)
+               return pd_to_genpd(dev->pm_domain);
+
+       return NULL;
+}
+
+/*
+ * This should only be used where we are certain that the pm_domain
+ * attached to the device is a genpd domain.
+ */
+static struct generic_pm_domain *dev_to_genpd(struct device *dev)
+{
+       if (IS_ERR_OR_NULL(dev->pm_domain))
+               return ERR_PTR(-EINVAL);
+
+       return pd_to_genpd(dev->pm_domain);
+}
+
+static int genpd_stop_dev(const struct generic_pm_domain *genpd,
+                         struct device *dev)
+{
+       return GENPD_DEV_CALLBACK(genpd, int, stop, dev);
+}
+
+static int genpd_start_dev(const struct generic_pm_domain *genpd,
+                          struct device *dev)
+{
+       return GENPD_DEV_CALLBACK(genpd, int, start, dev);
+}
+
+static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
+{
+       bool ret = false;
+
+       if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
+               ret = !!atomic_dec_and_test(&genpd->sd_count);
+
+       return ret;
+}
+
+static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
+{
+       atomic_inc(&genpd->sd_count);
+       smp_mb__after_atomic();
+}
+
+#ifdef CONFIG_DEBUG_FS
+static struct dentry *genpd_debugfs_dir;
+
+static void genpd_debug_add(struct generic_pm_domain *genpd);
+
+static void genpd_debug_remove(struct generic_pm_domain *genpd)
+{
+       if (!genpd_debugfs_dir)
+               return;
+
+       debugfs_lookup_and_remove(genpd->name, genpd_debugfs_dir);
+}
+
+static void genpd_update_accounting(struct generic_pm_domain *genpd)
+{
+       u64 delta, now;
+
+       now = ktime_get_mono_fast_ns();
+       if (now <= genpd->accounting_time)
+               return;
+
+       delta = now - genpd->accounting_time;
+
+       /*
+        * If genpd->status is active, it means we are just
+        * out of off and so update the idle time and vice
+        * versa.
+        */
+       if (genpd->status == GENPD_STATE_ON)
+               genpd->states[genpd->state_idx].idle_time += delta;
+       else
+               genpd->on_time += delta;
+
+       genpd->accounting_time = now;
+}
+#else
+static inline void genpd_debug_add(struct generic_pm_domain *genpd) {}
+static inline void genpd_debug_remove(struct generic_pm_domain *genpd) {}
+static inline void genpd_update_accounting(struct generic_pm_domain *genpd) {}
+#endif
+
+static int _genpd_reeval_performance_state(struct generic_pm_domain *genpd,
+                                          unsigned int state)
+{
+       struct generic_pm_domain_data *pd_data;
+       struct pm_domain_data *pdd;
+       struct gpd_link *link;
+
+       /* New requested state is same as Max requested state */
+       if (state == genpd->performance_state)
+               return state;
+
+       /* New requested state is higher than Max requested state */
+       if (state > genpd->performance_state)
+               return state;
+
+       /* Traverse all devices within the domain */
+       list_for_each_entry(pdd, &genpd->dev_list, list_node) {
+               pd_data = to_gpd_data(pdd);
+
+               if (pd_data->performance_state > state)
+                       state = pd_data->performance_state;
+       }
+
+       /*
+        * Traverse all sub-domains within the domain. This can be
+        * done without any additional locking as the link->performance_state
+        * field is protected by the parent genpd->lock, which is already taken.
+        *
+        * Also note that link->performance_state (subdomain's performance state
+        * requirement to parent domain) is different from
+        * link->child->performance_state (current performance state requirement
+        * of the devices/sub-domains of the subdomain) and so can have a
+        * different value.
+        *
+        * Note that we also take vote from powered-off sub-domains into account
+        * as the same is done for devices right now.
+        */
+       list_for_each_entry(link, &genpd->parent_links, parent_node) {
+               if (link->performance_state > state)
+                       state = link->performance_state;
+       }
+
+       return state;
+}
+
+static int genpd_xlate_performance_state(struct generic_pm_domain *genpd,
+                                        struct generic_pm_domain *parent,
+                                        unsigned int pstate)
+{
+       if (!parent->set_performance_state)
+               return pstate;
+
+       return dev_pm_opp_xlate_performance_state(genpd->opp_table,
+                                                 parent->opp_table,
+                                                 pstate);
+}
+
+static int _genpd_set_performance_state(struct generic_pm_domain *genpd,
+                                       unsigned int state, int depth)
+{
+       struct generic_pm_domain *parent;
+       struct gpd_link *link;
+       int parent_state, ret;
+
+       if (state == genpd->performance_state)
+               return 0;
+
+       /* Propagate to parents of genpd */
+       list_for_each_entry(link, &genpd->child_links, child_node) {
+               parent = link->parent;
+
+               /* Find parent's performance state */
+               ret = genpd_xlate_performance_state(genpd, parent, state);
+               if (unlikely(ret < 0))
+                       goto err;
+
+               parent_state = ret;
+
+               genpd_lock_nested(parent, depth + 1);
+
+               link->prev_performance_state = link->performance_state;
+               link->performance_state = parent_state;
+               parent_state = _genpd_reeval_performance_state(parent,
+                                               parent_state);
+               ret = _genpd_set_performance_state(parent, parent_state, depth + 1);
+               if (ret)
+                       link->performance_state = link->prev_performance_state;
+
+               genpd_unlock(parent);
+
+               if (ret)
+                       goto err;
+       }
+
+       if (genpd->set_performance_state) {
+               ret = genpd->set_performance_state(genpd, state);
+               if (ret)
+                       goto err;
+       }
+
+       genpd->performance_state = state;
+       return 0;
+
+err:
+       /* Encountered an error, lets rollback */
+       list_for_each_entry_continue_reverse(link, &genpd->child_links,
+                                            child_node) {
+               parent = link->parent;
+
+               genpd_lock_nested(parent, depth + 1);
+
+               parent_state = link->prev_performance_state;
+               link->performance_state = parent_state;
+
+               parent_state = _genpd_reeval_performance_state(parent,
+                                               parent_state);
+               if (_genpd_set_performance_state(parent, parent_state, depth + 1)) {
+                       pr_err("%s: Failed to roll back to %d performance state\n",
+                              parent->name, parent_state);
+               }
+
+               genpd_unlock(parent);
+       }
+
+       return ret;
+}
+
+static int genpd_set_performance_state(struct device *dev, unsigned int state)
+{
+       struct generic_pm_domain *genpd = dev_to_genpd(dev);
+       struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
+       unsigned int prev_state;
+       int ret;
+
+       prev_state = gpd_data->performance_state;
+       if (prev_state == state)
+               return 0;
+
+       gpd_data->performance_state = state;
+       state = _genpd_reeval_performance_state(genpd, state);
+
+       ret = _genpd_set_performance_state(genpd, state, 0);
+       if (ret)
+               gpd_data->performance_state = prev_state;
+
+       return ret;
+}
+
+static int genpd_drop_performance_state(struct device *dev)
+{
+       unsigned int prev_state = dev_gpd_data(dev)->performance_state;
+
+       if (!genpd_set_performance_state(dev, 0))
+               return prev_state;
+
+       return 0;
+}
+
+static void genpd_restore_performance_state(struct device *dev,
+                                           unsigned int state)
+{
+       if (state)
+               genpd_set_performance_state(dev, state);
+}
+
+static int genpd_dev_pm_set_performance_state(struct device *dev,
+                                             unsigned int state)
+{
+       struct generic_pm_domain *genpd = dev_to_genpd(dev);
+       int ret = 0;
+
+       genpd_lock(genpd);
+       if (pm_runtime_suspended(dev)) {
+               dev_gpd_data(dev)->rpm_pstate = state;
+       } else {
+               ret = genpd_set_performance_state(dev, state);
+               if (!ret)
+                       dev_gpd_data(dev)->rpm_pstate = 0;
+       }
+       genpd_unlock(genpd);
+
+       return ret;
+}
+
+/**
+ * dev_pm_genpd_set_performance_state- Set performance state of device's power
+ * domain.
+ *
+ * @dev: Device for which the performance-state needs to be set.
+ * @state: Target performance state of the device. This can be set as 0 when the
+ *        device doesn't have any performance state constraints left (And so
+ *        the device wouldn't participate anymore to find the target
+ *        performance state of the genpd).
+ *
+ * It is assumed that the users guarantee that the genpd wouldn't be detached
+ * while this routine is getting called.
+ *
+ * Returns 0 on success and negative error values on failures.
+ */
+int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state)
+{
+       struct generic_pm_domain *genpd;
+
+       genpd = dev_to_genpd_safe(dev);
+       if (!genpd)
+               return -ENODEV;
+
+       if (WARN_ON(!dev->power.subsys_data ||
+                    !dev->power.subsys_data->domain_data))
+               return -EINVAL;
+
+       return genpd_dev_pm_set_performance_state(dev, state);
+}
+EXPORT_SYMBOL_GPL(dev_pm_genpd_set_performance_state);
+
+/**
+ * dev_pm_genpd_set_next_wakeup - Notify PM framework of an impending wakeup.
+ *
+ * @dev: Device to handle
+ * @next: impending interrupt/wakeup for the device
+ *
+ *
+ * Allow devices to inform of the next wakeup. It's assumed that the users
+ * guarantee that the genpd wouldn't be detached while this routine is getting
+ * called. Additionally, it's also assumed that @dev isn't runtime suspended
+ * (RPM_SUSPENDED)."
+ * Although devices are expected to update the next_wakeup after the end of
+ * their usecase as well, it is possible the devices themselves may not know
+ * about that, so stale @next will be ignored when powering off the domain.
+ */
+void dev_pm_genpd_set_next_wakeup(struct device *dev, ktime_t next)
+{
+       struct generic_pm_domain *genpd;
+       struct gpd_timing_data *td;
+
+       genpd = dev_to_genpd_safe(dev);
+       if (!genpd)
+               return;
+
+       td = to_gpd_data(dev->power.subsys_data->domain_data)->td;
+       if (td)
+               td->next_wakeup = next;
+}
+EXPORT_SYMBOL_GPL(dev_pm_genpd_set_next_wakeup);
+
+/**
+ * dev_pm_genpd_get_next_hrtimer - Return the next_hrtimer for the genpd
+ * @dev: A device that is attached to the genpd.
+ *
+ * This routine should typically be called for a device, at the point of when a
+ * GENPD_NOTIFY_PRE_OFF notification has been sent for it.
+ *
+ * Returns the aggregated value of the genpd's next hrtimer or KTIME_MAX if no
+ * valid value have been set.
+ */
+ktime_t dev_pm_genpd_get_next_hrtimer(struct device *dev)
+{
+       struct generic_pm_domain *genpd;
+
+       genpd = dev_to_genpd_safe(dev);
+       if (!genpd)
+               return KTIME_MAX;
+
+       if (genpd->gd)
+               return genpd->gd->next_hrtimer;
+
+       return KTIME_MAX;
+}
+EXPORT_SYMBOL_GPL(dev_pm_genpd_get_next_hrtimer);
+
+/*
+ * dev_pm_genpd_synced_poweroff - Next power off should be synchronous
+ *
+ * @dev: A device that is attached to the genpd.
+ *
+ * Allows a consumer of the genpd to notify the provider that the next power off
+ * should be synchronous.
+ *
+ * It is assumed that the users guarantee that the genpd wouldn't be detached
+ * while this routine is getting called.
+ */
+void dev_pm_genpd_synced_poweroff(struct device *dev)
+{
+       struct generic_pm_domain *genpd;
+
+       genpd = dev_to_genpd_safe(dev);
+       if (!genpd)
+               return;
+
+       genpd_lock(genpd);
+       genpd->synced_poweroff = true;
+       genpd_unlock(genpd);
+}
+EXPORT_SYMBOL_GPL(dev_pm_genpd_synced_poweroff);
+
+static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed)
+{
+       unsigned int state_idx = genpd->state_idx;
+       ktime_t time_start;
+       s64 elapsed_ns;
+       int ret;
+
+       /* Notify consumers that we are about to power on. */
+       ret = raw_notifier_call_chain_robust(&genpd->power_notifiers,
+                                            GENPD_NOTIFY_PRE_ON,
+                                            GENPD_NOTIFY_OFF, NULL);
+       ret = notifier_to_errno(ret);
+       if (ret)
+               return ret;
+
+       if (!genpd->power_on)
+               goto out;
+
+       timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
+       if (!timed) {
+               ret = genpd->power_on(genpd);
+               if (ret)
+                       goto err;
+
+               goto out;
+       }
+
+       time_start = ktime_get();
+       ret = genpd->power_on(genpd);
+       if (ret)
+               goto err;
+
+       elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
+       if (elapsed_ns <= genpd->states[state_idx].power_on_latency_ns)
+               goto out;
+
+       genpd->states[state_idx].power_on_latency_ns = elapsed_ns;
+       genpd->gd->max_off_time_changed = true;
+       pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
+                genpd->name, "on", elapsed_ns);
+
+out:
+       raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL);
+       genpd->synced_poweroff = false;
+       return 0;
+err:
+       raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF,
+                               NULL);
+       return ret;
+}
+
+static int _genpd_power_off(struct generic_pm_domain *genpd, bool timed)
+{
+       unsigned int state_idx = genpd->state_idx;
+       ktime_t time_start;
+       s64 elapsed_ns;
+       int ret;
+
+       /* Notify consumers that we are about to power off. */
+       ret = raw_notifier_call_chain_robust(&genpd->power_notifiers,
+                                            GENPD_NOTIFY_PRE_OFF,
+                                            GENPD_NOTIFY_ON, NULL);
+       ret = notifier_to_errno(ret);
+       if (ret)
+               return ret;
+
+       if (!genpd->power_off)
+               goto out;
+
+       timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
+       if (!timed) {
+               ret = genpd->power_off(genpd);
+               if (ret)
+                       goto busy;
+
+               goto out;
+       }
+
+       time_start = ktime_get();
+       ret = genpd->power_off(genpd);
+       if (ret)
+               goto busy;
+
+       elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
+       if (elapsed_ns <= genpd->states[state_idx].power_off_latency_ns)
+               goto out;
+
+       genpd->states[state_idx].power_off_latency_ns = elapsed_ns;
+       genpd->gd->max_off_time_changed = true;
+       pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
+                genpd->name, "off", elapsed_ns);
+
+out:
+       raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF,
+                               NULL);
+       return 0;
+busy:
+       raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL);
+       return ret;
+}
+
+/**
+ * genpd_queue_power_off_work - Queue up the execution of genpd_power_off().
+ * @genpd: PM domain to power off.
+ *
+ * Queue up the execution of genpd_power_off() unless it's already been done
+ * before.
+ */
+static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
+{
+       queue_work(pm_wq, &genpd->power_off_work);
+}
+
+/**
+ * genpd_power_off - Remove power from a given PM domain.
+ * @genpd: PM domain to power down.
+ * @one_dev_on: If invoked from genpd's ->runtime_suspend|resume() callback, the
+ * RPM status of the releated device is in an intermediate state, not yet turned
+ * into RPM_SUSPENDED. This means genpd_power_off() must allow one device to not
+ * be RPM_SUSPENDED, while it tries to power off the PM domain.
+ * @depth: nesting count for lockdep.
+ *
+ * If all of the @genpd's devices have been suspended and all of its subdomains
+ * have been powered down, remove power from @genpd.
+ */
+static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on,
+                          unsigned int depth)
+{
+       struct pm_domain_data *pdd;
+       struct gpd_link *link;
+       unsigned int not_suspended = 0;
+       int ret;
+
+       /*
+        * Do not try to power off the domain in the following situations:
+        * (1) The domain is already in the "power off" state.
+        * (2) System suspend is in progress.
+        */
+       if (!genpd_status_on(genpd) || genpd->prepared_count > 0)
+               return 0;
+
+       /*
+        * Abort power off for the PM domain in the following situations:
+        * (1) The domain is configured as always on.
+        * (2) When the domain has a subdomain being powered on.
+        */
+       if (genpd_is_always_on(genpd) ||
+                       genpd_is_rpm_always_on(genpd) ||
+                       atomic_read(&genpd->sd_count) > 0)
+               return -EBUSY;
+
+       /*
+        * The children must be in their deepest (powered-off) states to allow
+        * the parent to be powered off. Note that, there's no need for
+        * additional locking, as powering on a child, requires the parent's
+        * lock to be acquired first.
+        */
+       list_for_each_entry(link, &genpd->parent_links, parent_node) {
+               struct generic_pm_domain *child = link->child;
+               if (child->state_idx < child->state_count - 1)
+                       return -EBUSY;
+       }
+
+       list_for_each_entry(pdd, &genpd->dev_list, list_node) {
+               /*
+                * Do not allow PM domain to be powered off, when an IRQ safe
+                * device is part of a non-IRQ safe domain.
+                */
+               if (!pm_runtime_suspended(pdd->dev) ||
+                       irq_safe_dev_in_sleep_domain(pdd->dev, genpd))
+                       not_suspended++;
+       }
+
+       if (not_suspended > 1 || (not_suspended == 1 && !one_dev_on))
+               return -EBUSY;
+
+       if (genpd->gov && genpd->gov->power_down_ok) {
+               if (!genpd->gov->power_down_ok(&genpd->domain))
+                       return -EAGAIN;
+       }
+
+       /* Default to shallowest state. */
+       if (!genpd->gov)
+               genpd->state_idx = 0;
+
+       /* Don't power off, if a child domain is waiting to power on. */
+       if (atomic_read(&genpd->sd_count) > 0)
+               return -EBUSY;
+
+       ret = _genpd_power_off(genpd, true);
+       if (ret) {
+               genpd->states[genpd->state_idx].rejected++;
+               return ret;
+       }
+
+       genpd->status = GENPD_STATE_OFF;
+       genpd_update_accounting(genpd);
+       genpd->states[genpd->state_idx].usage++;
+
+       list_for_each_entry(link, &genpd->child_links, child_node) {
+               genpd_sd_counter_dec(link->parent);
+               genpd_lock_nested(link->parent, depth + 1);
+               genpd_power_off(link->parent, false, depth + 1);
+               genpd_unlock(link->parent);
+       }
+
+       return 0;
+}
+
+/**
+ * genpd_power_on - Restore power to a given PM domain and its parents.
+ * @genpd: PM domain to power up.
+ * @depth: nesting count for lockdep.
+ *
+ * Restore power to @genpd and all of its parents so that it is possible to
+ * resume a device belonging to it.
+ */
+static int genpd_power_on(struct generic_pm_domain *genpd, unsigned int depth)
+{
+       struct gpd_link *link;
+       int ret = 0;
+
+       if (genpd_status_on(genpd))
+               return 0;
+
+       /*
+        * The list is guaranteed not to change while the loop below is being
+        * executed, unless one of the parents' .power_on() callbacks fiddles
+        * with it.
+        */
+       list_for_each_entry(link, &genpd->child_links, child_node) {
+               struct generic_pm_domain *parent = link->parent;
+
+               genpd_sd_counter_inc(parent);
+
+               genpd_lock_nested(parent, depth + 1);
+               ret = genpd_power_on(parent, depth + 1);
+               genpd_unlock(parent);
+
+               if (ret) {
+                       genpd_sd_counter_dec(parent);
+                       goto err;
+               }
+       }
+
+       ret = _genpd_power_on(genpd, true);
+       if (ret)
+               goto err;
+
+       genpd->status = GENPD_STATE_ON;
+       genpd_update_accounting(genpd);
+
+       return 0;
+
+ err:
+       list_for_each_entry_continue_reverse(link,
+                                       &genpd->child_links,
+                                       child_node) {
+               genpd_sd_counter_dec(link->parent);
+               genpd_lock_nested(link->parent, depth + 1);
+               genpd_power_off(link->parent, false, depth + 1);
+               genpd_unlock(link->parent);
+       }
+
+       return ret;
+}
+
+static int genpd_dev_pm_start(struct device *dev)
+{
+       struct generic_pm_domain *genpd = dev_to_genpd(dev);
+
+       return genpd_start_dev(genpd, dev);
+}
+
+static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
+                                    unsigned long val, void *ptr)
+{
+       struct generic_pm_domain_data *gpd_data;
+       struct device *dev;
+
+       gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
+       dev = gpd_data->base.dev;
+
+       for (;;) {
+               struct generic_pm_domain *genpd = ERR_PTR(-ENODATA);
+               struct pm_domain_data *pdd;
+               struct gpd_timing_data *td;
+
+               spin_lock_irq(&dev->power.lock);
+
+               pdd = dev->power.subsys_data ?
+                               dev->power.subsys_data->domain_data : NULL;
+               if (pdd) {
+                       td = to_gpd_data(pdd)->td;
+                       if (td) {
+                               td->constraint_changed = true;
+                               genpd = dev_to_genpd(dev);
+                       }
+               }
+
+               spin_unlock_irq(&dev->power.lock);
+
+               if (!IS_ERR(genpd)) {
+                       genpd_lock(genpd);
+                       genpd->gd->max_off_time_changed = true;
+                       genpd_unlock(genpd);
+               }
+
+               dev = dev->parent;
+               if (!dev || dev->power.ignore_children)
+                       break;
+       }
+
+       return NOTIFY_DONE;
+}
+
+/**
+ * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
+ * @work: Work structure used for scheduling the execution of this function.
+ */
+static void genpd_power_off_work_fn(struct work_struct *work)
+{
+       struct generic_pm_domain *genpd;
+
+       genpd = container_of(work, struct generic_pm_domain, power_off_work);
+
+       genpd_lock(genpd);
+       genpd_power_off(genpd, false, 0);
+       genpd_unlock(genpd);
+}
+
+/**
+ * __genpd_runtime_suspend - walk the hierarchy of ->runtime_suspend() callbacks
+ * @dev: Device to handle.
+ */
+static int __genpd_runtime_suspend(struct device *dev)
+{
+       int (*cb)(struct device *__dev);
+
+       if (dev->type && dev->type->pm)
+               cb = dev->type->pm->runtime_suspend;
+       else if (dev->class && dev->class->pm)
+               cb = dev->class->pm->runtime_suspend;
+       else if (dev->bus && dev->bus->pm)
+               cb = dev->bus->pm->runtime_suspend;
+       else
+               cb = NULL;
+
+       if (!cb && dev->driver && dev->driver->pm)
+               cb = dev->driver->pm->runtime_suspend;
+
+       return cb ? cb(dev) : 0;
+}
+
+/**
+ * __genpd_runtime_resume - walk the hierarchy of ->runtime_resume() callbacks
+ * @dev: Device to handle.
+ */
+static int __genpd_runtime_resume(struct device *dev)
+{
+       int (*cb)(struct device *__dev);
+
+       if (dev->type && dev->type->pm)
+               cb = dev->type->pm->runtime_resume;
+       else if (dev->class && dev->class->pm)
+               cb = dev->class->pm->runtime_resume;
+       else if (dev->bus && dev->bus->pm)
+               cb = dev->bus->pm->runtime_resume;
+       else
+               cb = NULL;
+
+       if (!cb && dev->driver && dev->driver->pm)
+               cb = dev->driver->pm->runtime_resume;
+
+       return cb ? cb(dev) : 0;
+}
+
+/**
+ * genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
+ * @dev: Device to suspend.
+ *
+ * Carry out a runtime suspend of a device under the assumption that its
+ * pm_domain field points to the domain member of an object of type
+ * struct generic_pm_domain representing a PM domain consisting of I/O devices.
+ */
+static int genpd_runtime_suspend(struct device *dev)
+{
+       struct generic_pm_domain *genpd;
+       bool (*suspend_ok)(struct device *__dev);
+       struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
+       struct gpd_timing_data *td = gpd_data->td;
+       bool runtime_pm = pm_runtime_enabled(dev);
+       ktime_t time_start = 0;
+       s64 elapsed_ns;
+       int ret;
+
+       dev_dbg(dev, "%s()\n", __func__);
+
+       genpd = dev_to_genpd(dev);
+       if (IS_ERR(genpd))
+               return -EINVAL;
+
+       /*
+        * A runtime PM centric subsystem/driver may re-use the runtime PM
+        * callbacks for other purposes than runtime PM. In those scenarios
+        * runtime PM is disabled. Under these circumstances, we shall skip
+        * validating/measuring the PM QoS latency.
+        */
+       suspend_ok = genpd->gov ? genpd->gov->suspend_ok : NULL;
+       if (runtime_pm && suspend_ok && !suspend_ok(dev))
+               return -EBUSY;
+
+       /* Measure suspend latency. */
+       if (td && runtime_pm)
+               time_start = ktime_get();
+
+       ret = __genpd_runtime_suspend(dev);
+       if (ret)
+               return ret;
+
+       ret = genpd_stop_dev(genpd, dev);
+       if (ret) {
+               __genpd_runtime_resume(dev);
+               return ret;
+       }
+
+       /* Update suspend latency value if the measured time exceeds it. */
+       if (td && runtime_pm) {
+               elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
+               if (elapsed_ns > td->suspend_latency_ns) {
+                       td->suspend_latency_ns = elapsed_ns;
+                       dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
+                               elapsed_ns);
+                       genpd->gd->max_off_time_changed = true;
+                       td->constraint_changed = true;
+               }
+       }
+
+       /*
+        * If power.irq_safe is set, this routine may be run with
+        * IRQs disabled, so suspend only if the PM domain also is irq_safe.
+        */
+       if (irq_safe_dev_in_sleep_domain(dev, genpd))
+               return 0;
+
+       genpd_lock(genpd);
+       genpd_power_off(genpd, true, 0);
+       gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
+       genpd_unlock(genpd);
+
+       return 0;
+}
+
+/**
+ * genpd_runtime_resume - Resume a device belonging to I/O PM domain.
+ * @dev: Device to resume.
+ *
+ * Carry out a runtime resume of a device under the assumption that its
+ * pm_domain field points to the domain member of an object of type
+ * struct generic_pm_domain representing a PM domain consisting of I/O devices.
+ */
+static int genpd_runtime_resume(struct device *dev)
+{
+       struct generic_pm_domain *genpd;
+       struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
+       struct gpd_timing_data *td = gpd_data->td;
+       bool timed = td && pm_runtime_enabled(dev);
+       ktime_t time_start = 0;
+       s64 elapsed_ns;
+       int ret;
+
+       dev_dbg(dev, "%s()\n", __func__);
+
+       genpd = dev_to_genpd(dev);
+       if (IS_ERR(genpd))
+               return -EINVAL;
+
+       /*
+        * As we don't power off a non IRQ safe domain, which holds
+        * an IRQ safe device, we don't need to restore power to it.
+        */
+       if (irq_safe_dev_in_sleep_domain(dev, genpd))
+               goto out;
+
+       genpd_lock(genpd);
+       genpd_restore_performance_state(dev, gpd_data->rpm_pstate);
+       ret = genpd_power_on(genpd, 0);
+       genpd_unlock(genpd);
+
+       if (ret)
+               return ret;
+
+ out:
+       /* Measure resume latency. */
+       if (timed)
+               time_start = ktime_get();
+
+       ret = genpd_start_dev(genpd, dev);
+       if (ret)
+               goto err_poweroff;
+
+       ret = __genpd_runtime_resume(dev);
+       if (ret)
+               goto err_stop;
+
+       /* Update resume latency value if the measured time exceeds it. */
+       if (timed) {
+               elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
+               if (elapsed_ns > td->resume_latency_ns) {
+                       td->resume_latency_ns = elapsed_ns;
+                       dev_dbg(dev, "resume latency exceeded, %lld ns\n",
+                               elapsed_ns);
+                       genpd->gd->max_off_time_changed = true;
+                       td->constraint_changed = true;
+               }
+       }
+
+       return 0;
+
+err_stop:
+       genpd_stop_dev(genpd, dev);
+err_poweroff:
+       if (!pm_runtime_is_irq_safe(dev) || genpd_is_irq_safe(genpd)) {
+               genpd_lock(genpd);
+               genpd_power_off(genpd, true, 0);
+               gpd_data->rpm_pstate = genpd_drop_performance_state(dev);
+               genpd_unlock(genpd);
+       }
+
+       return ret;
+}
+
+static bool pd_ignore_unused;
+static int __init pd_ignore_unused_setup(char *__unused)
+{
+       pd_ignore_unused = true;
+       return 1;
+}
+__setup("pd_ignore_unused", pd_ignore_unused_setup);
+
+/**
+ * genpd_power_off_unused - Power off all PM domains with no devices in use.
+ */
+static int __init genpd_power_off_unused(void)
+{
+       struct generic_pm_domain *genpd;
+
+       if (pd_ignore_unused) {
+               pr_warn("genpd: Not disabling unused power domains\n");
+               return 0;
+       }
+
+       mutex_lock(&gpd_list_lock);
+
+       list_for_each_entry(genpd, &gpd_list, gpd_list_node)
+               genpd_queue_power_off_work(genpd);
+
+       mutex_unlock(&gpd_list_lock);
+
+       return 0;
+}
+late_initcall(genpd_power_off_unused);
+
+#ifdef CONFIG_PM_SLEEP
+
+/**
+ * genpd_sync_power_off - Synchronously power off a PM domain and its parents.
+ * @genpd: PM domain to power off, if possible.
+ * @use_lock: use the lock.
+ * @depth: nesting count for lockdep.
+ *
+ * Check if the given PM domain can be powered off (during system suspend or
+ * hibernation) and do that if so.  Also, in that case propagate to its parents.
+ *
+ * This function is only called in "noirq" and "syscore" stages of system power
+ * transitions. The "noirq" callbacks may be executed asynchronously, thus in
+ * these cases the lock must be held.
+ */
+static void genpd_sync_power_off(struct generic_pm_domain *genpd, bool use_lock,
+                                unsigned int depth)
+{
+       struct gpd_link *link;
+
+       if (!genpd_status_on(genpd) || genpd_is_always_on(genpd))
+               return;
+
+       if (genpd->suspended_count != genpd->device_count
+           || atomic_read(&genpd->sd_count) > 0)
+               return;
+
+       /* Check that the children are in their deepest (powered-off) state. */
+       list_for_each_entry(link, &genpd->parent_links, parent_node) {
+               struct generic_pm_domain *child = link->child;
+               if (child->state_idx < child->state_count - 1)
+                       return;
+       }
+
+       /* Choose the deepest state when suspending */
+       genpd->state_idx = genpd->state_count - 1;
+       if (_genpd_power_off(genpd, false))
+               return;
+
+       genpd->status = GENPD_STATE_OFF;
+
+       list_for_each_entry(link, &genpd->child_links, child_node) {
+               genpd_sd_counter_dec(link->parent);
+
+               if (use_lock)
+                       genpd_lock_nested(link->parent, depth + 1);
+
+               genpd_sync_power_off(link->parent, use_lock, depth + 1);
+
+               if (use_lock)
+                       genpd_unlock(link->parent);
+       }
+}
+
+/**
+ * genpd_sync_power_on - Synchronously power on a PM domain and its parents.
+ * @genpd: PM domain to power on.
+ * @use_lock: use the lock.
+ * @depth: nesting count for lockdep.
+ *
+ * This function is only called in "noirq" and "syscore" stages of system power
+ * transitions. The "noirq" callbacks may be executed asynchronously, thus in
+ * these cases the lock must be held.
+ */
+static void genpd_sync_power_on(struct generic_pm_domain *genpd, bool use_lock,
+                               unsigned int depth)
+{
+       struct gpd_link *link;
+
+       if (genpd_status_on(genpd))
+               return;
+
+       list_for_each_entry(link, &genpd->child_links, child_node) {
+               genpd_sd_counter_inc(link->parent);
+
+               if (use_lock)
+                       genpd_lock_nested(link->parent, depth + 1);
+
+               genpd_sync_power_on(link->parent, use_lock, depth + 1);
+
+               if (use_lock)
+                       genpd_unlock(link->parent);
+       }
+
+       _genpd_power_on(genpd, false);
+       genpd->status = GENPD_STATE_ON;
+}
+
+/**
+ * genpd_prepare - Start power transition of a device in a PM domain.
+ * @dev: Device to start the transition of.
+ *
+ * Start a power transition of a device (during a system-wide power transition)
+ * under the assumption that its pm_domain field points to the domain member of
+ * an object of type struct generic_pm_domain representing a PM domain
+ * consisting of I/O devices.
+ */
+static int genpd_prepare(struct device *dev)
+{
+       struct generic_pm_domain *genpd;
+       int ret;
+
+       dev_dbg(dev, "%s()\n", __func__);
+
+       genpd = dev_to_genpd(dev);
+       if (IS_ERR(genpd))
+               return -EINVAL;
+
+       genpd_lock(genpd);
+
+       if (genpd->prepared_count++ == 0)
+               genpd->suspended_count = 0;
+
+       genpd_unlock(genpd);
+
+       ret = pm_generic_prepare(dev);
+       if (ret < 0) {
+               genpd_lock(genpd);
+
+               genpd->prepared_count--;
+
+               genpd_unlock(genpd);
+       }
+
+       /* Never return 1, as genpd don't cope with the direct_complete path. */
+       return ret >= 0 ? 0 : ret;
+}
+
+/**
+ * genpd_finish_suspend - Completion of suspend or hibernation of device in an
+ *   I/O pm domain.
+ * @dev: Device to suspend.
+ * @suspend_noirq: Generic suspend_noirq callback.
+ * @resume_noirq: Generic resume_noirq callback.
+ *
+ * Stop the device and remove power from the domain if all devices in it have
+ * been stopped.
+ */
+static int genpd_finish_suspend(struct device *dev,
+                               int (*suspend_noirq)(struct device *dev),
+                               int (*resume_noirq)(struct device *dev))
+{
+       struct generic_pm_domain *genpd;
+       int ret = 0;
+
+       genpd = dev_to_genpd(dev);
+       if (IS_ERR(genpd))
+               return -EINVAL;
+
+       ret = suspend_noirq(dev);
+       if (ret)
+               return ret;
+
+       if (device_wakeup_path(dev) && genpd_is_active_wakeup(genpd))
+               return 0;
+
+       if (genpd->dev_ops.stop && genpd->dev_ops.start &&
+           !pm_runtime_status_suspended(dev)) {
+               ret = genpd_stop_dev(genpd, dev);
+               if (ret) {
+                       resume_noirq(dev);
+                       return ret;
+               }
+       }
+
+       genpd_lock(genpd);
+       genpd->suspended_count++;
+       genpd_sync_power_off(genpd, true, 0);
+       genpd_unlock(genpd);
+
+       return 0;
+}
+
+/**
+ * genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
+ * @dev: Device to suspend.
+ *
+ * Stop the device and remove power from the domain if all devices in it have
+ * been stopped.
+ */
+static int genpd_suspend_noirq(struct device *dev)
+{
+       dev_dbg(dev, "%s()\n", __func__);
+
+       return genpd_finish_suspend(dev,
+                                   pm_generic_suspend_noirq,
+                                   pm_generic_resume_noirq);
+}
+
+/**
+ * genpd_finish_resume - Completion of resume of device in an I/O PM domain.
+ * @dev: Device to resume.
+ * @resume_noirq: Generic resume_noirq callback.
+ *
+ * Restore power to the device's PM domain, if necessary, and start the device.
+ */
+static int genpd_finish_resume(struct device *dev,
+                              int (*resume_noirq)(struct device *dev))
+{
+       struct generic_pm_domain *genpd;
+       int ret;
+
+       dev_dbg(dev, "%s()\n", __func__);
+
+       genpd = dev_to_genpd(dev);
+       if (IS_ERR(genpd))
+               return -EINVAL;
+
+       if (device_wakeup_path(dev) && genpd_is_active_wakeup(genpd))
+               return resume_noirq(dev);
+
+       genpd_lock(genpd);
+       genpd_sync_power_on(genpd, true, 0);
+       genpd->suspended_count--;
+       genpd_unlock(genpd);
+
+       if (genpd->dev_ops.stop && genpd->dev_ops.start &&
+           !pm_runtime_status_suspended(dev)) {
+               ret = genpd_start_dev(genpd, dev);
+               if (ret)
+                       return ret;
+       }
+
+       return pm_generic_resume_noirq(dev);
+}
+
+/**
+ * genpd_resume_noirq - Start of resume of device in an I/O PM domain.
+ * @dev: Device to resume.
+ *
+ * Restore power to the device's PM domain, if necessary, and start the device.
+ */
+static int genpd_resume_noirq(struct device *dev)
+{
+       dev_dbg(dev, "%s()\n", __func__);
+
+       return genpd_finish_resume(dev, pm_generic_resume_noirq);
+}
+
+/**
+ * genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
+ * @dev: Device to freeze.
+ *
+ * Carry out a late freeze of a device under the assumption that its
+ * pm_domain field points to the domain member of an object of type
+ * struct generic_pm_domain representing a power domain consisting of I/O
+ * devices.
+ */
+static int genpd_freeze_noirq(struct device *dev)
+{
+       dev_dbg(dev, "%s()\n", __func__);
+
+       return genpd_finish_suspend(dev,
+                                   pm_generic_freeze_noirq,
+                                   pm_generic_thaw_noirq);
+}
+
+/**
+ * genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
+ * @dev: Device to thaw.
+ *
+ * Start the device, unless power has been removed from the domain already
+ * before the system transition.
+ */
+static int genpd_thaw_noirq(struct device *dev)
+{
+       dev_dbg(dev, "%s()\n", __func__);
+
+       return genpd_finish_resume(dev, pm_generic_thaw_noirq);
+}
+
+/**
+ * genpd_poweroff_noirq - Completion of hibernation of device in an
+ *   I/O PM domain.
+ * @dev: Device to poweroff.
+ *
+ * Stop the device and remove power from the domain if all devices in it have
+ * been stopped.
+ */
+static int genpd_poweroff_noirq(struct device *dev)
+{
+       dev_dbg(dev, "%s()\n", __func__);
+
+       return genpd_finish_suspend(dev,
+                                   pm_generic_poweroff_noirq,
+                                   pm_generic_restore_noirq);
+}
+
+/**
+ * genpd_restore_noirq - Start of restore of device in an I/O PM domain.
+ * @dev: Device to resume.
+ *
+ * Make sure the domain will be in the same power state as before the
+ * hibernation the system is resuming from and start the device if necessary.
+ */
+static int genpd_restore_noirq(struct device *dev)
+{
+       dev_dbg(dev, "%s()\n", __func__);
+
+       return genpd_finish_resume(dev, pm_generic_restore_noirq);
+}
+
+/**
+ * genpd_complete - Complete power transition of a device in a power domain.
+ * @dev: Device to complete the transition of.
+ *
+ * Complete a power transition of a device (during a system-wide power
+ * transition) under the assumption that its pm_domain field points to the
+ * domain member of an object of type struct generic_pm_domain representing
+ * a power domain consisting of I/O devices.
+ */
+static void genpd_complete(struct device *dev)
+{
+       struct generic_pm_domain *genpd;
+
+       dev_dbg(dev, "%s()\n", __func__);
+
+       genpd = dev_to_genpd(dev);
+       if (IS_ERR(genpd))
+               return;
+
+       pm_generic_complete(dev);
+
+       genpd_lock(genpd);
+
+       genpd->prepared_count--;
+       if (!genpd->prepared_count)
+               genpd_queue_power_off_work(genpd);
+
+       genpd_unlock(genpd);
+}
+
+static void genpd_switch_state(struct device *dev, bool suspend)
+{
+       struct generic_pm_domain *genpd;
+       bool use_lock;
+
+       genpd = dev_to_genpd_safe(dev);
+       if (!genpd)
+               return;
+
+       use_lock = genpd_is_irq_safe(genpd);
+
+       if (use_lock)
+               genpd_lock(genpd);
+
+       if (suspend) {
+               genpd->suspended_count++;
+               genpd_sync_power_off(genpd, use_lock, 0);
+       } else {
+               genpd_sync_power_on(genpd, use_lock, 0);
+               genpd->suspended_count--;
+       }
+
+       if (use_lock)
+               genpd_unlock(genpd);
+}
+
+/**
+ * dev_pm_genpd_suspend - Synchronously try to suspend the genpd for @dev
+ * @dev: The device that is attached to the genpd, that can be suspended.
+ *
+ * This routine should typically be called for a device that needs to be
+ * suspended during the syscore suspend phase. It may also be called during
+ * suspend-to-idle to suspend a corresponding CPU device that is attached to a
+ * genpd.
+ */
+void dev_pm_genpd_suspend(struct device *dev)
+{
+       genpd_switch_state(dev, true);
+}
+EXPORT_SYMBOL_GPL(dev_pm_genpd_suspend);
+
+/**
+ * dev_pm_genpd_resume - Synchronously try to resume the genpd for @dev
+ * @dev: The device that is attached to the genpd, which needs to be resumed.
+ *
+ * This routine should typically be called for a device that needs to be resumed
+ * during the syscore resume phase. It may also be called during suspend-to-idle
+ * to resume a corresponding CPU device that is attached to a genpd.
+ */
+void dev_pm_genpd_resume(struct device *dev)
+{
+       genpd_switch_state(dev, false);
+}
+EXPORT_SYMBOL_GPL(dev_pm_genpd_resume);
+
+#else /* !CONFIG_PM_SLEEP */
+
+#define genpd_prepare          NULL
+#define genpd_suspend_noirq    NULL
+#define genpd_resume_noirq     NULL
+#define genpd_freeze_noirq     NULL
+#define genpd_thaw_noirq       NULL
+#define genpd_poweroff_noirq   NULL
+#define genpd_restore_noirq    NULL
+#define genpd_complete         NULL
+
+#endif /* CONFIG_PM_SLEEP */
+
+static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
+                                                          bool has_governor)
+{
+       struct generic_pm_domain_data *gpd_data;
+       struct gpd_timing_data *td;
+       int ret;
+
+       ret = dev_pm_get_subsys_data(dev);
+       if (ret)
+               return ERR_PTR(ret);
+
+       gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
+       if (!gpd_data) {
+               ret = -ENOMEM;
+               goto err_put;
+       }
+
+       gpd_data->base.dev = dev;
+       gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
+
+       /* Allocate data used by a governor. */
+       if (has_governor) {
+               td = kzalloc(sizeof(*td), GFP_KERNEL);
+               if (!td) {
+                       ret = -ENOMEM;
+                       goto err_free;
+               }
+
+               td->constraint_changed = true;
+               td->effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
+               td->next_wakeup = KTIME_MAX;
+               gpd_data->td = td;
+       }
+
+       spin_lock_irq(&dev->power.lock);
+
+       if (dev->power.subsys_data->domain_data)
+               ret = -EINVAL;
+       else
+               dev->power.subsys_data->domain_data = &gpd_data->base;
+
+       spin_unlock_irq(&dev->power.lock);
+
+       if (ret)
+               goto err_free;
+
+       return gpd_data;
+
+ err_free:
+       kfree(gpd_data->td);
+       kfree(gpd_data);
+ err_put:
+       dev_pm_put_subsys_data(dev);
+       return ERR_PTR(ret);
+}
+
+static void genpd_free_dev_data(struct device *dev,
+                               struct generic_pm_domain_data *gpd_data)
+{
+       spin_lock_irq(&dev->power.lock);
+
+       dev->power.subsys_data->domain_data = NULL;
+
+       spin_unlock_irq(&dev->power.lock);
+
+       kfree(gpd_data->td);
+       kfree(gpd_data);
+       dev_pm_put_subsys_data(dev);
+}
+
+static void genpd_update_cpumask(struct generic_pm_domain *genpd,
+                                int cpu, bool set, unsigned int depth)
+{
+       struct gpd_link *link;
+
+       if (!genpd_is_cpu_domain(genpd))
+               return;
+
+       list_for_each_entry(link, &genpd->child_links, child_node) {
+               struct generic_pm_domain *parent = link->parent;
+
+               genpd_lock_nested(parent, depth + 1);
+               genpd_update_cpumask(parent, cpu, set, depth + 1);
+               genpd_unlock(parent);
+       }
+
+       if (set)
+               cpumask_set_cpu(cpu, genpd->cpus);
+       else
+               cpumask_clear_cpu(cpu, genpd->cpus);
+}
+
+static void genpd_set_cpumask(struct generic_pm_domain *genpd, int cpu)
+{
+       if (cpu >= 0)
+               genpd_update_cpumask(genpd, cpu, true, 0);
+}
+
+static void genpd_clear_cpumask(struct generic_pm_domain *genpd, int cpu)
+{
+       if (cpu >= 0)
+               genpd_update_cpumask(genpd, cpu, false, 0);
+}
+
+static int genpd_get_cpu(struct generic_pm_domain *genpd, struct device *dev)
+{
+       int cpu;
+
+       if (!genpd_is_cpu_domain(genpd))
+               return -1;
+
+       for_each_possible_cpu(cpu) {
+               if (get_cpu_device(cpu) == dev)
+                       return cpu;
+       }
+
+       return -1;
+}
+
+static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
+                           struct device *base_dev)
+{
+       struct genpd_governor_data *gd = genpd->gd;
+       struct generic_pm_domain_data *gpd_data;
+       int ret;
+
+       dev_dbg(dev, "%s()\n", __func__);
+
+       gpd_data = genpd_alloc_dev_data(dev, gd);
+       if (IS_ERR(gpd_data))
+               return PTR_ERR(gpd_data);
+
+       gpd_data->cpu = genpd_get_cpu(genpd, base_dev);
+
+       ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
+       if (ret)
+               goto out;
+
+       genpd_lock(genpd);
+
+       genpd_set_cpumask(genpd, gpd_data->cpu);
+       dev_pm_domain_set(dev, &genpd->domain);
+
+       genpd->device_count++;
+       if (gd)
+               gd->max_off_time_changed = true;
+
+       list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
+
+       genpd_unlock(genpd);
+ out:
+       if (ret)
+               genpd_free_dev_data(dev, gpd_data);
+       else
+               dev_pm_qos_add_notifier(dev, &gpd_data->nb,
+                                       DEV_PM_QOS_RESUME_LATENCY);
+
+       return ret;
+}
+
+/**
+ * pm_genpd_add_device - Add a device to an I/O PM domain.
+ * @genpd: PM domain to add the device to.
+ * @dev: Device to be added.
+ */
+int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev)
+{
+       int ret;
+
+       if (!genpd || !dev)
+               return -EINVAL;
+
+       mutex_lock(&gpd_list_lock);
+       ret = genpd_add_device(genpd, dev, dev);
+       mutex_unlock(&gpd_list_lock);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(pm_genpd_add_device);
+
+static int genpd_remove_device(struct generic_pm_domain *genpd,
+                              struct device *dev)
+{
+       struct generic_pm_domain_data *gpd_data;
+       struct pm_domain_data *pdd;
+       int ret = 0;
+
+       dev_dbg(dev, "%s()\n", __func__);
+
+       pdd = dev->power.subsys_data->domain_data;
+       gpd_data = to_gpd_data(pdd);
+       dev_pm_qos_remove_notifier(dev, &gpd_data->nb,
+                                  DEV_PM_QOS_RESUME_LATENCY);
+
+       genpd_lock(genpd);
+
+       if (genpd->prepared_count > 0) {
+               ret = -EAGAIN;
+               goto out;
+       }
+
+       genpd->device_count--;
+       if (genpd->gd)
+               genpd->gd->max_off_time_changed = true;
+
+       genpd_clear_cpumask(genpd, gpd_data->cpu);
+       dev_pm_domain_set(dev, NULL);
+
+       list_del_init(&pdd->list_node);
+
+       genpd_unlock(genpd);
+
+       if (genpd->detach_dev)
+               genpd->detach_dev(genpd, dev);
+
+       genpd_free_dev_data(dev, gpd_data);
+
+       return 0;
+
+ out:
+       genpd_unlock(genpd);
+       dev_pm_qos_add_notifier(dev, &gpd_data->nb, DEV_PM_QOS_RESUME_LATENCY);
+
+       return ret;
+}
+
+/**
+ * pm_genpd_remove_device - Remove a device from an I/O PM domain.
+ * @dev: Device to be removed.
+ */
+int pm_genpd_remove_device(struct device *dev)
+{
+       struct generic_pm_domain *genpd = dev_to_genpd_safe(dev);
+
+       if (!genpd)
+               return -EINVAL;
+
+       return genpd_remove_device(genpd, dev);
+}
+EXPORT_SYMBOL_GPL(pm_genpd_remove_device);
+
+/**
+ * dev_pm_genpd_add_notifier - Add a genpd power on/off notifier for @dev
+ *
+ * @dev: Device that should be associated with the notifier
+ * @nb: The notifier block to register
+ *
+ * Users may call this function to add a genpd power on/off notifier for an
+ * attached @dev. Only one notifier per device is allowed. The notifier is
+ * sent when genpd is powering on/off the PM domain.
+ *
+ * It is assumed that the user guarantee that the genpd wouldn't be detached
+ * while this routine is getting called.
+ *
+ * Returns 0 on success and negative error values on failures.
+ */
+int dev_pm_genpd_add_notifier(struct device *dev, struct notifier_block *nb)
+{
+       struct generic_pm_domain *genpd;
+       struct generic_pm_domain_data *gpd_data;
+       int ret;
+
+       genpd = dev_to_genpd_safe(dev);
+       if (!genpd)
+               return -ENODEV;
+
+       if (WARN_ON(!dev->power.subsys_data ||
+                    !dev->power.subsys_data->domain_data))
+               return -EINVAL;
+
+       gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
+       if (gpd_data->power_nb)
+               return -EEXIST;
+
+       genpd_lock(genpd);
+       ret = raw_notifier_chain_register(&genpd->power_notifiers, nb);
+       genpd_unlock(genpd);
+
+       if (ret) {
+               dev_warn(dev, "failed to add notifier for PM domain %s\n",
+                        genpd->name);
+               return ret;
+       }
+
+       gpd_data->power_nb = nb;
+       return 0;
+}
+EXPORT_SYMBOL_GPL(dev_pm_genpd_add_notifier);
+
+/**
+ * dev_pm_genpd_remove_notifier - Remove a genpd power on/off notifier for @dev
+ *
+ * @dev: Device that is associated with the notifier
+ *
+ * Users may call this function to remove a genpd power on/off notifier for an
+ * attached @dev.
+ *
+ * It is assumed that the user guarantee that the genpd wouldn't be detached
+ * while this routine is getting called.
+ *
+ * Returns 0 on success and negative error values on failures.
+ */
+int dev_pm_genpd_remove_notifier(struct device *dev)
+{
+       struct generic_pm_domain *genpd;
+       struct generic_pm_domain_data *gpd_data;
+       int ret;
+
+       genpd = dev_to_genpd_safe(dev);
+       if (!genpd)
+               return -ENODEV;
+
+       if (WARN_ON(!dev->power.subsys_data ||
+                    !dev->power.subsys_data->domain_data))
+               return -EINVAL;
+
+       gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
+       if (!gpd_data->power_nb)
+               return -ENODEV;
+
+       genpd_lock(genpd);
+       ret = raw_notifier_chain_unregister(&genpd->power_notifiers,
+                                           gpd_data->power_nb);
+       genpd_unlock(genpd);
+
+       if (ret) {
+               dev_warn(dev, "failed to remove notifier for PM domain %s\n",
+                        genpd->name);
+               return ret;
+       }
+
+       gpd_data->power_nb = NULL;
+       return 0;
+}
+EXPORT_SYMBOL_GPL(dev_pm_genpd_remove_notifier);
+
+static int genpd_add_subdomain(struct generic_pm_domain *genpd,
+                              struct generic_pm_domain *subdomain)
+{
+       struct gpd_link *link, *itr;
+       int ret = 0;
+
+       if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
+           || genpd == subdomain)
+               return -EINVAL;
+
+       /*
+        * If the domain can be powered on/off in an IRQ safe
+        * context, ensure that the subdomain can also be
+        * powered on/off in that context.
+        */
+       if (!genpd_is_irq_safe(genpd) && genpd_is_irq_safe(subdomain)) {
+               WARN(1, "Parent %s of subdomain %s must be IRQ safe\n",
+                               genpd->name, subdomain->name);
+               return -EINVAL;
+       }
+
+       link = kzalloc(sizeof(*link), GFP_KERNEL);
+       if (!link)
+               return -ENOMEM;
+
+       genpd_lock(subdomain);
+       genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
+
+       if (!genpd_status_on(genpd) && genpd_status_on(subdomain)) {
+               ret = -EINVAL;
+               goto out;
+       }
+
+       list_for_each_entry(itr, &genpd->parent_links, parent_node) {
+               if (itr->child == subdomain && itr->parent == genpd) {
+                       ret = -EINVAL;
+                       goto out;
+               }
+       }
+
+       link->parent = genpd;
+       list_add_tail(&link->parent_node, &genpd->parent_links);
+       link->child = subdomain;
+       list_add_tail(&link->child_node, &subdomain->child_links);
+       if (genpd_status_on(subdomain))
+               genpd_sd_counter_inc(genpd);
+
+ out:
+       genpd_unlock(genpd);
+       genpd_unlock(subdomain);
+       if (ret)
+               kfree(link);
+       return ret;
+}
+
+/**
+ * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
+ * @genpd: Leader PM domain to add the subdomain to.
+ * @subdomain: Subdomain to be added.
+ */
+int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
+                          struct generic_pm_domain *subdomain)
+{
+       int ret;
+
+       mutex_lock(&gpd_list_lock);
+       ret = genpd_add_subdomain(genpd, subdomain);
+       mutex_unlock(&gpd_list_lock);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(pm_genpd_add_subdomain);
+
+/**
+ * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
+ * @genpd: Leader PM domain to remove the subdomain from.
+ * @subdomain: Subdomain to be removed.
+ */
+int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
+                             struct generic_pm_domain *subdomain)
+{
+       struct gpd_link *l, *link;
+       int ret = -EINVAL;
+
+       if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
+               return -EINVAL;
+
+       genpd_lock(subdomain);
+       genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
+
+       if (!list_empty(&subdomain->parent_links) || subdomain->device_count) {
+               pr_warn("%s: unable to remove subdomain %s\n",
+                       genpd->name, subdomain->name);
+               ret = -EBUSY;
+               goto out;
+       }
+
+       list_for_each_entry_safe(link, l, &genpd->parent_links, parent_node) {
+               if (link->child != subdomain)
+                       continue;
+
+               list_del(&link->parent_node);
+               list_del(&link->child_node);
+               kfree(link);
+               if (genpd_status_on(subdomain))
+                       genpd_sd_counter_dec(genpd);
+
+               ret = 0;
+               break;
+       }
+
+out:
+       genpd_unlock(genpd);
+       genpd_unlock(subdomain);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain);
+
+static void genpd_free_default_power_state(struct genpd_power_state *states,
+                                          unsigned int state_count)
+{
+       kfree(states);
+}
+
+static int genpd_set_default_power_state(struct generic_pm_domain *genpd)
+{
+       struct genpd_power_state *state;
+
+       state = kzalloc(sizeof(*state), GFP_KERNEL);
+       if (!state)
+               return -ENOMEM;
+
+       genpd->states = state;
+       genpd->state_count = 1;
+       genpd->free_states = genpd_free_default_power_state;
+
+       return 0;
+}
+
+static int genpd_alloc_data(struct generic_pm_domain *genpd)
+{
+       struct genpd_governor_data *gd = NULL;
+       int ret;
+
+       if (genpd_is_cpu_domain(genpd) &&
+           !zalloc_cpumask_var(&genpd->cpus, GFP_KERNEL))
+               return -ENOMEM;
+
+       if (genpd->gov) {
+               gd = kzalloc(sizeof(*gd), GFP_KERNEL);
+               if (!gd) {
+                       ret = -ENOMEM;
+                       goto free;
+               }
+
+               gd->max_off_time_ns = -1;
+               gd->max_off_time_changed = true;
+               gd->next_wakeup = KTIME_MAX;
+               gd->next_hrtimer = KTIME_MAX;
+       }
+
+       /* Use only one "off" state if there were no states declared */
+       if (genpd->state_count == 0) {
+               ret = genpd_set_default_power_state(genpd);
+               if (ret)
+                       goto free;
+       }
+
+       genpd->gd = gd;
+       return 0;
+
+free:
+       if (genpd_is_cpu_domain(genpd))
+               free_cpumask_var(genpd->cpus);
+       kfree(gd);
+       return ret;
+}
+
+static void genpd_free_data(struct generic_pm_domain *genpd)
+{
+       if (genpd_is_cpu_domain(genpd))
+               free_cpumask_var(genpd->cpus);
+       if (genpd->free_states)
+               genpd->free_states(genpd->states, genpd->state_count);
+       kfree(genpd->gd);
+}
+
+static void genpd_lock_init(struct generic_pm_domain *genpd)
+{
+       if (genpd->flags & GENPD_FLAG_IRQ_SAFE) {
+               spin_lock_init(&genpd->slock);
+               genpd->lock_ops = &genpd_spin_ops;
+       } else {
+               mutex_init(&genpd->mlock);
+               genpd->lock_ops = &genpd_mtx_ops;
+       }
+}
+
+/**
+ * pm_genpd_init - Initialize a generic I/O PM domain object.
+ * @genpd: PM domain object to initialize.
+ * @gov: PM domain governor to associate with the domain (may be NULL).
+ * @is_off: Initial value of the domain's power_is_off field.
+ *
+ * Returns 0 on successful initialization, else a negative error code.
+ */
+int pm_genpd_init(struct generic_pm_domain *genpd,
+                 struct dev_power_governor *gov, bool is_off)
+{
+       int ret;
+
+       if (IS_ERR_OR_NULL(genpd))
+               return -EINVAL;
+
+       INIT_LIST_HEAD(&genpd->parent_links);
+       INIT_LIST_HEAD(&genpd->child_links);
+       INIT_LIST_HEAD(&genpd->dev_list);
+       RAW_INIT_NOTIFIER_HEAD(&genpd->power_notifiers);
+       genpd_lock_init(genpd);
+       genpd->gov = gov;
+       INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
+       atomic_set(&genpd->sd_count, 0);
+       genpd->status = is_off ? GENPD_STATE_OFF : GENPD_STATE_ON;
+       genpd->device_count = 0;
+       genpd->provider = NULL;
+       genpd->has_provider = false;
+       genpd->accounting_time = ktime_get_mono_fast_ns();
+       genpd->domain.ops.runtime_suspend = genpd_runtime_suspend;
+       genpd->domain.ops.runtime_resume = genpd_runtime_resume;
+       genpd->domain.ops.prepare = genpd_prepare;
+       genpd->domain.ops.suspend_noirq = genpd_suspend_noirq;
+       genpd->domain.ops.resume_noirq = genpd_resume_noirq;
+       genpd->domain.ops.freeze_noirq = genpd_freeze_noirq;
+       genpd->domain.ops.thaw_noirq = genpd_thaw_noirq;
+       genpd->domain.ops.poweroff_noirq = genpd_poweroff_noirq;
+       genpd->domain.ops.restore_noirq = genpd_restore_noirq;
+       genpd->domain.ops.complete = genpd_complete;
+       genpd->domain.start = genpd_dev_pm_start;
+       genpd->domain.set_performance_state = genpd_dev_pm_set_performance_state;
+
+       if (genpd->flags & GENPD_FLAG_PM_CLK) {
+               genpd->dev_ops.stop = pm_clk_suspend;
+               genpd->dev_ops.start = pm_clk_resume;
+       }
+
+       /* The always-on governor works better with the corresponding flag. */
+       if (gov == &pm_domain_always_on_gov)
+               genpd->flags |= GENPD_FLAG_RPM_ALWAYS_ON;
+
+       /* Always-on domains must be powered on at initialization. */
+       if ((genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd)) &&
+                       !genpd_status_on(genpd)) {
+               pr_err("always-on PM domain %s is not on\n", genpd->name);
+               return -EINVAL;
+       }
+
+       /* Multiple states but no governor doesn't make sense. */
+       if (!gov && genpd->state_count > 1)
+               pr_warn("%s: no governor for states\n", genpd->name);
+
+       ret = genpd_alloc_data(genpd);
+       if (ret)
+               return ret;
+
+       device_initialize(&genpd->dev);
+       dev_set_name(&genpd->dev, "%s", genpd->name);
+
+       mutex_lock(&gpd_list_lock);
+       list_add(&genpd->gpd_list_node, &gpd_list);
+       mutex_unlock(&gpd_list_lock);
+       genpd_debug_add(genpd);
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(pm_genpd_init);
+
+static int genpd_remove(struct generic_pm_domain *genpd)
+{
+       struct gpd_link *l, *link;
+
+       if (IS_ERR_OR_NULL(genpd))
+               return -EINVAL;
+
+       genpd_lock(genpd);
+
+       if (genpd->has_provider) {
+               genpd_unlock(genpd);
+               pr_err("Provider present, unable to remove %s\n", genpd->name);
+               return -EBUSY;
+       }
+
+       if (!list_empty(&genpd->parent_links) || genpd->device_count) {
+               genpd_unlock(genpd);
+               pr_err("%s: unable to remove %s\n", __func__, genpd->name);
+               return -EBUSY;
+       }
+
+       list_for_each_entry_safe(link, l, &genpd->child_links, child_node) {
+               list_del(&link->parent_node);
+               list_del(&link->child_node);
+               kfree(link);
+       }
+
+       list_del(&genpd->gpd_list_node);
+       genpd_unlock(genpd);
+       genpd_debug_remove(genpd);
+       cancel_work_sync(&genpd->power_off_work);
+       genpd_free_data(genpd);
+
+       pr_debug("%s: removed %s\n", __func__, genpd->name);
+
+       return 0;
+}
+
+/**
+ * pm_genpd_remove - Remove a generic I/O PM domain
+ * @genpd: Pointer to PM domain that is to be removed.
+ *
+ * To remove the PM domain, this function:
+ *  - Removes the PM domain as a subdomain to any parent domains,
+ *    if it was added.
+ *  - Removes the PM domain from the list of registered PM domains.
+ *
+ * The PM domain will only be removed, if the associated provider has
+ * been removed, it is not a parent to any other PM domain and has no
+ * devices associated with it.
+ */
+int pm_genpd_remove(struct generic_pm_domain *genpd)
+{
+       int ret;
+
+       mutex_lock(&gpd_list_lock);
+       ret = genpd_remove(genpd);
+       mutex_unlock(&gpd_list_lock);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(pm_genpd_remove);
+
+#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
+
+/*
+ * Device Tree based PM domain providers.
+ *
+ * The code below implements generic device tree based PM domain providers that
+ * bind device tree nodes with generic PM domains registered in the system.
+ *
+ * Any driver that registers generic PM domains and needs to support binding of
+ * devices to these domains is supposed to register a PM domain provider, which
+ * maps a PM domain specifier retrieved from the device tree to a PM domain.
+ *
+ * Two simple mapping functions have been provided for convenience:
+ *  - genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
+ *  - genpd_xlate_onecell() for mapping of multiple PM domains per node by
+ *    index.
+ */
+
+/**
+ * struct of_genpd_provider - PM domain provider registration structure
+ * @link: Entry in global list of PM domain providers
+ * @node: Pointer to device tree node of PM domain provider
+ * @xlate: Provider-specific xlate callback mapping a set of specifier cells
+ *         into a PM domain.
+ * @data: context pointer to be passed into @xlate callback
+ */
+struct of_genpd_provider {
+       struct list_head link;
+       struct device_node *node;
+       genpd_xlate_t xlate;
+       void *data;
+};
+
+/* List of registered PM domain providers. */
+static LIST_HEAD(of_genpd_providers);
+/* Mutex to protect the list above. */
+static DEFINE_MUTEX(of_genpd_mutex);
+
+/**
+ * genpd_xlate_simple() - Xlate function for direct node-domain mapping
+ * @genpdspec: OF phandle args to map into a PM domain
+ * @data: xlate function private data - pointer to struct generic_pm_domain
+ *
+ * This is a generic xlate function that can be used to model PM domains that
+ * have their own device tree nodes. The private data of xlate function needs
+ * to be a valid pointer to struct generic_pm_domain.
+ */
+static struct generic_pm_domain *genpd_xlate_simple(
+                                       struct of_phandle_args *genpdspec,
+                                       void *data)
+{
+       return data;
+}
+
+/**
+ * genpd_xlate_onecell() - Xlate function using a single index.
+ * @genpdspec: OF phandle args to map into a PM domain
+ * @data: xlate function private data - pointer to struct genpd_onecell_data
+ *
+ * This is a generic xlate function that can be used to model simple PM domain
+ * controllers that have one device tree node and provide multiple PM domains.
+ * A single cell is used as an index into an array of PM domains specified in
+ * the genpd_onecell_data struct when registering the provider.
+ */
+static struct generic_pm_domain *genpd_xlate_onecell(
+                                       struct of_phandle_args *genpdspec,
+                                       void *data)
+{
+       struct genpd_onecell_data *genpd_data = data;
+       unsigned int idx = genpdspec->args[0];
+
+       if (genpdspec->args_count != 1)
+               return ERR_PTR(-EINVAL);
+
+       if (idx >= genpd_data->num_domains) {
+               pr_err("%s: invalid domain index %u\n", __func__, idx);
+               return ERR_PTR(-EINVAL);
+       }
+
+       if (!genpd_data->domains[idx])
+               return ERR_PTR(-ENOENT);
+
+       return genpd_data->domains[idx];
+}
+
+/**
+ * genpd_add_provider() - Register a PM domain provider for a node
+ * @np: Device node pointer associated with the PM domain provider.
+ * @xlate: Callback for decoding PM domain from phandle arguments.
+ * @data: Context pointer for @xlate callback.
+ */
+static int genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
+                             void *data)
+{
+       struct of_genpd_provider *cp;
+
+       cp = kzalloc(sizeof(*cp), GFP_KERNEL);
+       if (!cp)
+               return -ENOMEM;
+
+       cp->node = of_node_get(np);
+       cp->data = data;
+       cp->xlate = xlate;
+       fwnode_dev_initialized(&np->fwnode, true);
+
+       mutex_lock(&of_genpd_mutex);
+       list_add(&cp->link, &of_genpd_providers);
+       mutex_unlock(&of_genpd_mutex);
+       pr_debug("Added domain provider from %pOF\n", np);
+
+       return 0;
+}
+
+static bool genpd_present(const struct generic_pm_domain *genpd)
+{
+       bool ret = false;
+       const struct generic_pm_domain *gpd;
+
+       mutex_lock(&gpd_list_lock);
+       list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
+               if (gpd == genpd) {
+                       ret = true;
+                       break;
+               }
+       }
+       mutex_unlock(&gpd_list_lock);
+
+       return ret;
+}
+
+/**
+ * of_genpd_add_provider_simple() - Register a simple PM domain provider
+ * @np: Device node pointer associated with the PM domain provider.
+ * @genpd: Pointer to PM domain associated with the PM domain provider.
+ */
+int of_genpd_add_provider_simple(struct device_node *np,
+                                struct generic_pm_domain *genpd)
+{
+       int ret;
+
+       if (!np || !genpd)
+               return -EINVAL;
+
+       if (!genpd_present(genpd))
+               return -EINVAL;
+
+       genpd->dev.of_node = np;
+
+       /* Parse genpd OPP table */
+       if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
+               ret = dev_pm_opp_of_add_table(&genpd->dev);
+               if (ret)
+                       return dev_err_probe(&genpd->dev, ret, "Failed to add OPP table\n");
+
+               /*
+                * Save table for faster processing while setting performance
+                * state.
+                */
+               genpd->opp_table = dev_pm_opp_get_opp_table(&genpd->dev);
+               WARN_ON(IS_ERR(genpd->opp_table));
+       }
+
+       ret = genpd_add_provider(np, genpd_xlate_simple, genpd);
+       if (ret) {
+               if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
+                       dev_pm_opp_put_opp_table(genpd->opp_table);
+                       dev_pm_opp_of_remove_table(&genpd->dev);
+               }
+
+               return ret;
+       }
+
+       genpd->provider = &np->fwnode;
+       genpd->has_provider = true;
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(of_genpd_add_provider_simple);
+
+/**
+ * of_genpd_add_provider_onecell() - Register a onecell PM domain provider
+ * @np: Device node pointer associated with the PM domain provider.
+ * @data: Pointer to the data associated with the PM domain provider.
+ */
+int of_genpd_add_provider_onecell(struct device_node *np,
+                                 struct genpd_onecell_data *data)
+{
+       struct generic_pm_domain *genpd;
+       unsigned int i;
+       int ret = -EINVAL;
+
+       if (!np || !data)
+               return -EINVAL;
+
+       if (!data->xlate)
+               data->xlate = genpd_xlate_onecell;
+
+       for (i = 0; i < data->num_domains; i++) {
+               genpd = data->domains[i];
+
+               if (!genpd)
+                       continue;
+               if (!genpd_present(genpd))
+                       goto error;
+
+               genpd->dev.of_node = np;
+
+               /* Parse genpd OPP table */
+               if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
+                       ret = dev_pm_opp_of_add_table_indexed(&genpd->dev, i);
+                       if (ret) {
+                               dev_err_probe(&genpd->dev, ret,
+                                             "Failed to add OPP table for index %d\n", i);
+                               goto error;
+                       }
+
+                       /*
+                        * Save table for faster processing while setting
+                        * performance state.
+                        */
+                       genpd->opp_table = dev_pm_opp_get_opp_table(&genpd->dev);
+                       WARN_ON(IS_ERR(genpd->opp_table));
+               }
+
+               genpd->provider = &np->fwnode;
+               genpd->has_provider = true;
+       }
+
+       ret = genpd_add_provider(np, data->xlate, data);
+       if (ret < 0)
+               goto error;
+
+       return 0;
+
+error:
+       while (i--) {
+               genpd = data->domains[i];
+
+               if (!genpd)
+                       continue;
+
+               genpd->provider = NULL;
+               genpd->has_provider = false;
+
+               if (!genpd_is_opp_table_fw(genpd) && genpd->set_performance_state) {
+                       dev_pm_opp_put_opp_table(genpd->opp_table);
+                       dev_pm_opp_of_remove_table(&genpd->dev);
+               }
+       }
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(of_genpd_add_provider_onecell);
+
+/**
+ * of_genpd_del_provider() - Remove a previously registered PM domain provider
+ * @np: Device node pointer associated with the PM domain provider
+ */
+void of_genpd_del_provider(struct device_node *np)
+{
+       struct of_genpd_provider *cp, *tmp;
+       struct generic_pm_domain *gpd;
+
+       mutex_lock(&gpd_list_lock);
+       mutex_lock(&of_genpd_mutex);
+       list_for_each_entry_safe(cp, tmp, &of_genpd_providers, link) {
+               if (cp->node == np) {
+                       /*
+                        * For each PM domain associated with the
+                        * provider, set the 'has_provider' to false
+                        * so that the PM domain can be safely removed.
+                        */
+                       list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
+                               if (gpd->provider == &np->fwnode) {
+                                       gpd->has_provider = false;
+
+                                       if (genpd_is_opp_table_fw(gpd) || !gpd->set_performance_state)
+                                               continue;
+
+                                       dev_pm_opp_put_opp_table(gpd->opp_table);
+                                       dev_pm_opp_of_remove_table(&gpd->dev);
+                               }
+                       }
+
+                       fwnode_dev_initialized(&cp->node->fwnode, false);
+                       list_del(&cp->link);
+                       of_node_put(cp->node);
+                       kfree(cp);
+                       break;
+               }
+       }
+       mutex_unlock(&of_genpd_mutex);
+       mutex_unlock(&gpd_list_lock);
+}
+EXPORT_SYMBOL_GPL(of_genpd_del_provider);
+
+/**
+ * genpd_get_from_provider() - Look-up PM domain
+ * @genpdspec: OF phandle args to use for look-up
+ *
+ * Looks for a PM domain provider under the node specified by @genpdspec and if
+ * found, uses xlate function of the provider to map phandle args to a PM
+ * domain.
+ *
+ * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
+ * on failure.
+ */
+static struct generic_pm_domain *genpd_get_from_provider(
+                                       struct of_phandle_args *genpdspec)
+{
+       struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
+       struct of_genpd_provider *provider;
+
+       if (!genpdspec)
+               return ERR_PTR(-EINVAL);
+
+       mutex_lock(&of_genpd_mutex);
+
+       /* Check if we have such a provider in our array */
+       list_for_each_entry(provider, &of_genpd_providers, link) {
+               if (provider->node == genpdspec->np)
+                       genpd = provider->xlate(genpdspec, provider->data);
+               if (!IS_ERR(genpd))
+                       break;
+       }
+
+       mutex_unlock(&of_genpd_mutex);
+
+       return genpd;
+}
+
+/**
+ * of_genpd_add_device() - Add a device to an I/O PM domain
+ * @genpdspec: OF phandle args to use for look-up PM domain
+ * @dev: Device to be added.
+ *
+ * Looks-up an I/O PM domain based upon phandle args provided and adds
+ * the device to the PM domain. Returns a negative error code on failure.
+ */
+int of_genpd_add_device(struct of_phandle_args *genpdspec, struct device *dev)
+{
+       struct generic_pm_domain *genpd;
+       int ret;
+
+       if (!dev)
+               return -EINVAL;
+
+       mutex_lock(&gpd_list_lock);
+
+       genpd = genpd_get_from_provider(genpdspec);
+       if (IS_ERR(genpd)) {
+               ret = PTR_ERR(genpd);
+               goto out;
+       }
+
+       ret = genpd_add_device(genpd, dev, dev);
+
+out:
+       mutex_unlock(&gpd_list_lock);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(of_genpd_add_device);
+
+/**
+ * of_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
+ * @parent_spec: OF phandle args to use for parent PM domain look-up
+ * @subdomain_spec: OF phandle args to use for subdomain look-up
+ *
+ * Looks-up a parent PM domain and subdomain based upon phandle args
+ * provided and adds the subdomain to the parent PM domain. Returns a
+ * negative error code on failure.
+ */
+int of_genpd_add_subdomain(struct of_phandle_args *parent_spec,
+                          struct of_phandle_args *subdomain_spec)
+{
+       struct generic_pm_domain *parent, *subdomain;
+       int ret;
+
+       mutex_lock(&gpd_list_lock);
+
+       parent = genpd_get_from_provider(parent_spec);
+       if (IS_ERR(parent)) {
+               ret = PTR_ERR(parent);
+               goto out;
+       }
+
+       subdomain = genpd_get_from_provider(subdomain_spec);
+       if (IS_ERR(subdomain)) {
+               ret = PTR_ERR(subdomain);
+               goto out;
+       }
+
+       ret = genpd_add_subdomain(parent, subdomain);
+
+out:
+       mutex_unlock(&gpd_list_lock);
+
+       return ret == -ENOENT ? -EPROBE_DEFER : ret;
+}
+EXPORT_SYMBOL_GPL(of_genpd_add_subdomain);
+
+/**
+ * of_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
+ * @parent_spec: OF phandle args to use for parent PM domain look-up
+ * @subdomain_spec: OF phandle args to use for subdomain look-up
+ *
+ * Looks-up a parent PM domain and subdomain based upon phandle args
+ * provided and removes the subdomain from the parent PM domain. Returns a
+ * negative error code on failure.
+ */
+int of_genpd_remove_subdomain(struct of_phandle_args *parent_spec,
+                             struct of_phandle_args *subdomain_spec)
+{
+       struct generic_pm_domain *parent, *subdomain;
+       int ret;
+
+       mutex_lock(&gpd_list_lock);
+
+       parent = genpd_get_from_provider(parent_spec);
+       if (IS_ERR(parent)) {
+               ret = PTR_ERR(parent);
+               goto out;
+       }
+
+       subdomain = genpd_get_from_provider(subdomain_spec);
+       if (IS_ERR(subdomain)) {
+               ret = PTR_ERR(subdomain);
+               goto out;
+       }
+
+       ret = pm_genpd_remove_subdomain(parent, subdomain);
+
+out:
+       mutex_unlock(&gpd_list_lock);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(of_genpd_remove_subdomain);
+
+/**
+ * of_genpd_remove_last - Remove the last PM domain registered for a provider
+ * @np: Pointer to device node associated with provider
+ *
+ * Find the last PM domain that was added by a particular provider and
+ * remove this PM domain from the list of PM domains. The provider is
+ * identified by the 'provider' device structure that is passed. The PM
+ * domain will only be removed, if the provider associated with domain
+ * has been removed.
+ *
+ * Returns a valid pointer to struct generic_pm_domain on success or
+ * ERR_PTR() on failure.
+ */
+struct generic_pm_domain *of_genpd_remove_last(struct device_node *np)
+{
+       struct generic_pm_domain *gpd, *tmp, *genpd = ERR_PTR(-ENOENT);
+       int ret;
+
+       if (IS_ERR_OR_NULL(np))
+               return ERR_PTR(-EINVAL);
+
+       mutex_lock(&gpd_list_lock);
+       list_for_each_entry_safe(gpd, tmp, &gpd_list, gpd_list_node) {
+               if (gpd->provider == &np->fwnode) {
+                       ret = genpd_remove(gpd);
+                       genpd = ret ? ERR_PTR(ret) : gpd;
+                       break;
+               }
+       }
+       mutex_unlock(&gpd_list_lock);
+
+       return genpd;
+}
+EXPORT_SYMBOL_GPL(of_genpd_remove_last);
+
+static void genpd_release_dev(struct device *dev)
+{
+       of_node_put(dev->of_node);
+       kfree(dev);
+}
+
+static struct bus_type genpd_bus_type = {
+       .name           = "genpd",
+};
+
+/**
+ * genpd_dev_pm_detach - Detach a device from its PM domain.
+ * @dev: Device to detach.
+ * @power_off: Currently not used
+ *
+ * Try to locate a corresponding generic PM domain, which the device was
+ * attached to previously. If such is found, the device is detached from it.
+ */
+static void genpd_dev_pm_detach(struct device *dev, bool power_off)
+{
+       struct generic_pm_domain *pd;
+       unsigned int i;
+       int ret = 0;
+
+       pd = dev_to_genpd(dev);
+       if (IS_ERR(pd))
+               return;
+
+       dev_dbg(dev, "removing from PM domain %s\n", pd->name);
+
+       /* Drop the default performance state */
+       if (dev_gpd_data(dev)->default_pstate) {
+               dev_pm_genpd_set_performance_state(dev, 0);
+               dev_gpd_data(dev)->default_pstate = 0;
+       }
+
+       for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
+               ret = genpd_remove_device(pd, dev);
+               if (ret != -EAGAIN)
+                       break;
+
+               mdelay(i);
+               cond_resched();
+       }
+
+       if (ret < 0) {
+               dev_err(dev, "failed to remove from PM domain %s: %d",
+                       pd->name, ret);
+               return;
+       }
+
+       /* Check if PM domain can be powered off after removing this device. */
+       genpd_queue_power_off_work(pd);
+
+       /* Unregister the device if it was created by genpd. */
+       if (dev->bus == &genpd_bus_type)
+               device_unregister(dev);
+}
+
+static void genpd_dev_pm_sync(struct device *dev)
+{
+       struct generic_pm_domain *pd;
+
+       pd = dev_to_genpd(dev);
+       if (IS_ERR(pd))
+               return;
+
+       genpd_queue_power_off_work(pd);
+}
+
+static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
+                                unsigned int index, bool power_on)
+{
+       struct of_phandle_args pd_args;
+       struct generic_pm_domain *pd;
+       int pstate;
+       int ret;
+
+       ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
+                               "#power-domain-cells", index, &pd_args);
+       if (ret < 0)
+               return ret;
+
+       mutex_lock(&gpd_list_lock);
+       pd = genpd_get_from_provider(&pd_args);
+       of_node_put(pd_args.np);
+       if (IS_ERR(pd)) {
+               mutex_unlock(&gpd_list_lock);
+               dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
+                       __func__, PTR_ERR(pd));
+               return driver_deferred_probe_check_state(base_dev);
+       }
+
+       dev_dbg(dev, "adding to PM domain %s\n", pd->name);
+
+       ret = genpd_add_device(pd, dev, base_dev);
+       mutex_unlock(&gpd_list_lock);
+
+       if (ret < 0)
+               return dev_err_probe(dev, ret, "failed to add to PM domain %s\n", pd->name);
+
+       dev->pm_domain->detach = genpd_dev_pm_detach;
+       dev->pm_domain->sync = genpd_dev_pm_sync;
+
+       /* Set the default performance state */
+       pstate = of_get_required_opp_performance_state(dev->of_node, index);
+       if (pstate < 0 && pstate != -ENODEV && pstate != -EOPNOTSUPP) {
+               ret = pstate;
+               goto err;
+       } else if (pstate > 0) {
+               ret = dev_pm_genpd_set_performance_state(dev, pstate);
+               if (ret)
+                       goto err;
+               dev_gpd_data(dev)->default_pstate = pstate;
+       }
+
+       if (power_on) {
+               genpd_lock(pd);
+               ret = genpd_power_on(pd, 0);
+               genpd_unlock(pd);
+       }
+
+       if (ret) {
+               /* Drop the default performance state */
+               if (dev_gpd_data(dev)->default_pstate) {
+                       dev_pm_genpd_set_performance_state(dev, 0);
+                       dev_gpd_data(dev)->default_pstate = 0;
+               }
+
+               genpd_remove_device(pd, dev);
+               return -EPROBE_DEFER;
+       }
+
+       return 1;
+
+err:
+       dev_err(dev, "failed to set required performance state for power-domain %s: %d\n",
+               pd->name, ret);
+       genpd_remove_device(pd, dev);
+       return ret;
+}
+
+/**
+ * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
+ * @dev: Device to attach.
+ *
+ * Parse device's OF node to find a PM domain specifier. If such is found,
+ * attaches the device to retrieved pm_domain ops.
+ *
+ * Returns 1 on successfully attached PM domain, 0 when the device don't need a
+ * PM domain or when multiple power-domains exists for it, else a negative error
+ * code. Note that if a power-domain exists for the device, but it cannot be
+ * found or turned on, then return -EPROBE_DEFER to ensure that the device is
+ * not probed and to re-try again later.
+ */
+int genpd_dev_pm_attach(struct device *dev)
+{
+       if (!dev->of_node)
+               return 0;
+
+       /*
+        * Devices with multiple PM domains must be attached separately, as we
+        * can only attach one PM domain per device.
+        */
+       if (of_count_phandle_with_args(dev->of_node, "power-domains",
+                                      "#power-domain-cells") != 1)
+               return 0;
+
+       return __genpd_dev_pm_attach(dev, dev, 0, true);
+}
+EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
+
+/**
+ * genpd_dev_pm_attach_by_id - Associate a device with one of its PM domains.
+ * @dev: The device used to lookup the PM domain.
+ * @index: The index of the PM domain.
+ *
+ * Parse device's OF node to find a PM domain specifier at the provided @index.
+ * If such is found, creates a virtual device and attaches it to the retrieved
+ * pm_domain ops. To deal with detaching of the virtual device, the ->detach()
+ * callback in the struct dev_pm_domain are assigned to genpd_dev_pm_detach().
+ *
+ * Returns the created virtual device if successfully attached PM domain, NULL
+ * when the device don't need a PM domain, else an ERR_PTR() in case of
+ * failures. If a power-domain exists for the device, but cannot be found or
+ * turned on, then ERR_PTR(-EPROBE_DEFER) is returned to ensure that the device
+ * is not probed and to re-try again later.
+ */
+struct device *genpd_dev_pm_attach_by_id(struct device *dev,
+                                        unsigned int index)
+{
+       struct device *virt_dev;
+       int num_domains;
+       int ret;
+
+       if (!dev->of_node)
+               return NULL;
+
+       /* Verify that the index is within a valid range. */
+       num_domains = of_count_phandle_with_args(dev->of_node, "power-domains",
+                                                "#power-domain-cells");
+       if (index >= num_domains)
+               return NULL;
+
+       /* Allocate and register device on the genpd bus. */
+       virt_dev = kzalloc(sizeof(*virt_dev), GFP_KERNEL);
+       if (!virt_dev)
+               return ERR_PTR(-ENOMEM);
+
+       dev_set_name(virt_dev, "genpd:%u:%s", index, dev_name(dev));
+       virt_dev->bus = &genpd_bus_type;
+       virt_dev->release = genpd_release_dev;
+       virt_dev->of_node = of_node_get(dev->of_node);
+
+       ret = device_register(virt_dev);
+       if (ret) {
+               put_device(virt_dev);
+               return ERR_PTR(ret);
+       }
+
+       /* Try to attach the device to the PM domain at the specified index. */
+       ret = __genpd_dev_pm_attach(virt_dev, dev, index, false);
+       if (ret < 1) {
+               device_unregister(virt_dev);
+               return ret ? ERR_PTR(ret) : NULL;
+       }
+
+       pm_runtime_enable(virt_dev);
+       genpd_queue_power_off_work(dev_to_genpd(virt_dev));
+
+       return virt_dev;
+}
+EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id);
+
+/**
+ * genpd_dev_pm_attach_by_name - Associate a device with one of its PM domains.
+ * @dev: The device used to lookup the PM domain.
+ * @name: The name of the PM domain.
+ *
+ * Parse device's OF node to find a PM domain specifier using the
+ * power-domain-names DT property. For further description see
+ * genpd_dev_pm_attach_by_id().
+ */
+struct device *genpd_dev_pm_attach_by_name(struct device *dev, const char *name)
+{
+       int index;
+
+       if (!dev->of_node)
+               return NULL;
+
+       index = of_property_match_string(dev->of_node, "power-domain-names",
+                                        name);
+       if (index < 0)
+               return NULL;
+
+       return genpd_dev_pm_attach_by_id(dev, index);
+}
+
+static const struct of_device_id idle_state_match[] = {
+       { .compatible = "domain-idle-state", },
+       { }
+};
+
+static int genpd_parse_state(struct genpd_power_state *genpd_state,
+                                   struct device_node *state_node)
+{
+       int err;
+       u32 residency;
+       u32 entry_latency, exit_latency;
+
+       err = of_property_read_u32(state_node, "entry-latency-us",
+                                               &entry_latency);
+       if (err) {
+               pr_debug(" * %pOF missing entry-latency-us property\n",
+                        state_node);
+               return -EINVAL;
+       }
+
+       err = of_property_read_u32(state_node, "exit-latency-us",
+                                               &exit_latency);
+       if (err) {
+               pr_debug(" * %pOF missing exit-latency-us property\n",
+                        state_node);
+               return -EINVAL;
+       }
+
+       err = of_property_read_u32(state_node, "min-residency-us", &residency);
+       if (!err)
+               genpd_state->residency_ns = 1000LL * residency;
+
+       genpd_state->power_on_latency_ns = 1000LL * exit_latency;
+       genpd_state->power_off_latency_ns = 1000LL * entry_latency;
+       genpd_state->fwnode = &state_node->fwnode;
+
+       return 0;
+}
+
+static int genpd_iterate_idle_states(struct device_node *dn,
+                                    struct genpd_power_state *states)
+{
+       int ret;
+       struct of_phandle_iterator it;
+       struct device_node *np;
+       int i = 0;
+
+       ret = of_count_phandle_with_args(dn, "domain-idle-states", NULL);
+       if (ret <= 0)
+               return ret == -ENOENT ? 0 : ret;
+
+       /* Loop over the phandles until all the requested entry is found */
+       of_for_each_phandle(&it, ret, dn, "domain-idle-states", NULL, 0) {
+               np = it.node;
+               if (!of_match_node(idle_state_match, np))
+                       continue;
+
+               if (!of_device_is_available(np))
+                       continue;
+
+               if (states) {
+                       ret = genpd_parse_state(&states[i], np);
+                       if (ret) {
+                               pr_err("Parsing idle state node %pOF failed with err %d\n",
+                                      np, ret);
+                               of_node_put(np);
+                               return ret;
+                       }
+               }
+               i++;
+       }
+
+       return i;
+}
+
+/**
+ * of_genpd_parse_idle_states: Return array of idle states for the genpd.
+ *
+ * @dn: The genpd device node
+ * @states: The pointer to which the state array will be saved.
+ * @n: The count of elements in the array returned from this function.
+ *
+ * Returns the device states parsed from the OF node. The memory for the states
+ * is allocated by this function and is the responsibility of the caller to
+ * free the memory after use. If any or zero compatible domain idle states is
+ * found it returns 0 and in case of errors, a negative error code is returned.
+ */
+int of_genpd_parse_idle_states(struct device_node *dn,
+                       struct genpd_power_state **states, int *n)
+{
+       struct genpd_power_state *st;
+       int ret;
+
+       ret = genpd_iterate_idle_states(dn, NULL);
+       if (ret < 0)
+               return ret;
+
+       if (!ret) {
+               *states = NULL;
+               *n = 0;
+               return 0;
+       }
+
+       st = kcalloc(ret, sizeof(*st), GFP_KERNEL);
+       if (!st)
+               return -ENOMEM;
+
+       ret = genpd_iterate_idle_states(dn, st);
+       if (ret <= 0) {
+               kfree(st);
+               return ret < 0 ? ret : -EINVAL;
+       }
+
+       *states = st;
+       *n = ret;
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(of_genpd_parse_idle_states);
+
+static int __init genpd_bus_init(void)
+{
+       return bus_register(&genpd_bus_type);
+}
+core_initcall(genpd_bus_init);
+
+#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
+
+
+/***        debugfs support        ***/
+
+#ifdef CONFIG_DEBUG_FS
+/*
+ * TODO: This function is a slightly modified version of rtpm_status_show
+ * from sysfs.c, so generalize it.
+ */
+static void rtpm_status_str(struct seq_file *s, struct device *dev)
+{
+       static const char * const status_lookup[] = {
+               [RPM_ACTIVE] = "active",
+               [RPM_RESUMING] = "resuming",
+               [RPM_SUSPENDED] = "suspended",
+               [RPM_SUSPENDING] = "suspending"
+       };
+       const char *p = "";
+
+       if (dev->power.runtime_error)
+               p = "error";
+       else if (dev->power.disable_depth)
+               p = "unsupported";
+       else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup))
+               p = status_lookup[dev->power.runtime_status];
+       else
+               WARN_ON(1);
+
+       seq_printf(s, "%-25s  ", p);
+}
+
+static void perf_status_str(struct seq_file *s, struct device *dev)
+{
+       struct generic_pm_domain_data *gpd_data;
+
+       gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
+       seq_put_decimal_ull(s, "", gpd_data->performance_state);
+}
+
+static int genpd_summary_one(struct seq_file *s,
+                       struct generic_pm_domain *genpd)
+{
+       static const char * const status_lookup[] = {
+               [GENPD_STATE_ON] = "on",
+               [GENPD_STATE_OFF] = "off"
+       };
+       struct pm_domain_data *pm_data;
+       const char *kobj_path;
+       struct gpd_link *link;
+       char state[16];
+       int ret;
+
+       ret = genpd_lock_interruptible(genpd);
+       if (ret)
+               return -ERESTARTSYS;
+
+       if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
+               goto exit;
+       if (!genpd_status_on(genpd))
+               snprintf(state, sizeof(state), "%s-%u",
+                        status_lookup[genpd->status], genpd->state_idx);
+       else
+               snprintf(state, sizeof(state), "%s",
+                        status_lookup[genpd->status]);
+       seq_printf(s, "%-30s  %-50s %u", genpd->name, state, genpd->performance_state);
+
+       /*
+        * Modifications on the list require holding locks on both
+        * parent and child, so we are safe.
+        * Also genpd->name is immutable.
+        */
+       list_for_each_entry(link, &genpd->parent_links, parent_node) {
+               if (list_is_first(&link->parent_node, &genpd->parent_links))
+                       seq_printf(s, "\n%48s", " ");
+               seq_printf(s, "%s", link->child->name);
+               if (!list_is_last(&link->parent_node, &genpd->parent_links))
+                       seq_puts(s, ", ");
+       }
+
+       list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
+               kobj_path = kobject_get_path(&pm_data->dev->kobj,
+                               genpd_is_irq_safe(genpd) ?
+                               GFP_ATOMIC : GFP_KERNEL);
+               if (kobj_path == NULL)
+                       continue;
+
+               seq_printf(s, "\n    %-50s  ", kobj_path);
+               rtpm_status_str(s, pm_data->dev);
+               perf_status_str(s, pm_data->dev);
+               kfree(kobj_path);
+       }
+
+       seq_puts(s, "\n");
+exit:
+       genpd_unlock(genpd);
+
+       return 0;
+}
+
+static int summary_show(struct seq_file *s, void *data)
+{
+       struct generic_pm_domain *genpd;
+       int ret = 0;
+
+       seq_puts(s, "domain                          status          children                           performance\n");
+       seq_puts(s, "    /device                                             runtime status\n");
+       seq_puts(s, "----------------------------------------------------------------------------------------------\n");
+
+       ret = mutex_lock_interruptible(&gpd_list_lock);
+       if (ret)
+               return -ERESTARTSYS;
+
+       list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
+               ret = genpd_summary_one(s, genpd);
+               if (ret)
+                       break;
+       }
+       mutex_unlock(&gpd_list_lock);
+
+       return ret;
+}
+
+static int status_show(struct seq_file *s, void *data)
+{
+       static const char * const status_lookup[] = {
+               [GENPD_STATE_ON] = "on",
+               [GENPD_STATE_OFF] = "off"
+       };
+
+       struct generic_pm_domain *genpd = s->private;
+       int ret = 0;
+
+       ret = genpd_lock_interruptible(genpd);
+       if (ret)
+               return -ERESTARTSYS;
+
+       if (WARN_ON_ONCE(genpd->status >= ARRAY_SIZE(status_lookup)))
+               goto exit;
+
+       if (genpd->status == GENPD_STATE_OFF)
+               seq_printf(s, "%s-%u\n", status_lookup[genpd->status],
+                       genpd->state_idx);
+       else
+               seq_printf(s, "%s\n", status_lookup[genpd->status]);
+exit:
+       genpd_unlock(genpd);
+       return ret;
+}
+
+static int sub_domains_show(struct seq_file *s, void *data)
+{
+       struct generic_pm_domain *genpd = s->private;
+       struct gpd_link *link;
+       int ret = 0;
+
+       ret = genpd_lock_interruptible(genpd);
+       if (ret)
+               return -ERESTARTSYS;
+
+       list_for_each_entry(link, &genpd->parent_links, parent_node)
+               seq_printf(s, "%s\n", link->child->name);
+
+       genpd_unlock(genpd);
+       return ret;
+}
+
+static int idle_states_show(struct seq_file *s, void *data)
+{
+       struct generic_pm_domain *genpd = s->private;
+       u64 now, delta, idle_time = 0;
+       unsigned int i;
+       int ret = 0;
+
+       ret = genpd_lock_interruptible(genpd);
+       if (ret)
+               return -ERESTARTSYS;
+
+       seq_puts(s, "State          Time Spent(ms) Usage          Rejected\n");
+
+       for (i = 0; i < genpd->state_count; i++) {
+               idle_time += genpd->states[i].idle_time;
+
+               if (genpd->status == GENPD_STATE_OFF && genpd->state_idx == i) {
+                       now = ktime_get_mono_fast_ns();
+                       if (now > genpd->accounting_time) {
+                               delta = now - genpd->accounting_time;
+                               idle_time += delta;
+                       }
+               }
+
+               do_div(idle_time, NSEC_PER_MSEC);
+               seq_printf(s, "S%-13i %-14llu %-14llu %llu\n", i, idle_time,
+                          genpd->states[i].usage, genpd->states[i].rejected);
+       }
+
+       genpd_unlock(genpd);
+       return ret;
+}
+
+static int active_time_show(struct seq_file *s, void *data)
+{
+       struct generic_pm_domain *genpd = s->private;
+       u64 now, on_time, delta = 0;
+       int ret = 0;
+
+       ret = genpd_lock_interruptible(genpd);
+       if (ret)
+               return -ERESTARTSYS;
+
+       if (genpd->status == GENPD_STATE_ON) {
+               now = ktime_get_mono_fast_ns();
+               if (now > genpd->accounting_time)
+                       delta = now - genpd->accounting_time;
+       }
+
+       on_time = genpd->on_time + delta;
+       do_div(on_time, NSEC_PER_MSEC);
+       seq_printf(s, "%llu ms\n", on_time);
+
+       genpd_unlock(genpd);
+       return ret;
+}
+
+static int total_idle_time_show(struct seq_file *s, void *data)
+{
+       struct generic_pm_domain *genpd = s->private;
+       u64 now, delta, total = 0;
+       unsigned int i;
+       int ret = 0;
+
+       ret = genpd_lock_interruptible(genpd);
+       if (ret)
+               return -ERESTARTSYS;
+
+       for (i = 0; i < genpd->state_count; i++) {
+               total += genpd->states[i].idle_time;
+
+               if (genpd->status == GENPD_STATE_OFF && genpd->state_idx == i) {
+                       now = ktime_get_mono_fast_ns();
+                       if (now > genpd->accounting_time) {
+                               delta = now - genpd->accounting_time;
+                               total += delta;
+                       }
+               }
+       }
+
+       do_div(total, NSEC_PER_MSEC);
+       seq_printf(s, "%llu ms\n", total);
+
+       genpd_unlock(genpd);
+       return ret;
+}
+
+
+static int devices_show(struct seq_file *s, void *data)
+{
+       struct generic_pm_domain *genpd = s->private;
+       struct pm_domain_data *pm_data;
+       const char *kobj_path;
+       int ret = 0;
+
+       ret = genpd_lock_interruptible(genpd);
+       if (ret)
+               return -ERESTARTSYS;
+
+       list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
+               kobj_path = kobject_get_path(&pm_data->dev->kobj,
+                               genpd_is_irq_safe(genpd) ?
+                               GFP_ATOMIC : GFP_KERNEL);
+               if (kobj_path == NULL)
+                       continue;
+
+               seq_printf(s, "%s\n", kobj_path);
+               kfree(kobj_path);
+       }
+
+       genpd_unlock(genpd);
+       return ret;
+}
+
+static int perf_state_show(struct seq_file *s, void *data)
+{
+       struct generic_pm_domain *genpd = s->private;
+
+       if (genpd_lock_interruptible(genpd))
+               return -ERESTARTSYS;
+
+       seq_printf(s, "%u\n", genpd->performance_state);
+
+       genpd_unlock(genpd);
+       return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(summary);
+DEFINE_SHOW_ATTRIBUTE(status);
+DEFINE_SHOW_ATTRIBUTE(sub_domains);
+DEFINE_SHOW_ATTRIBUTE(idle_states);
+DEFINE_SHOW_ATTRIBUTE(active_time);
+DEFINE_SHOW_ATTRIBUTE(total_idle_time);
+DEFINE_SHOW_ATTRIBUTE(devices);
+DEFINE_SHOW_ATTRIBUTE(perf_state);
+
+static void genpd_debug_add(struct generic_pm_domain *genpd)
+{
+       struct dentry *d;
+
+       if (!genpd_debugfs_dir)
+               return;
+
+       d = debugfs_create_dir(genpd->name, genpd_debugfs_dir);
+
+       debugfs_create_file("current_state", 0444,
+                           d, genpd, &status_fops);
+       debugfs_create_file("sub_domains", 0444,
+                           d, genpd, &sub_domains_fops);
+       debugfs_create_file("idle_states", 0444,
+                           d, genpd, &idle_states_fops);
+       debugfs_create_file("active_time", 0444,
+                           d, genpd, &active_time_fops);
+       debugfs_create_file("total_idle_time", 0444,
+                           d, genpd, &total_idle_time_fops);
+       debugfs_create_file("devices", 0444,
+                           d, genpd, &devices_fops);
+       if (genpd->set_performance_state)
+               debugfs_create_file("perf_state", 0444,
+                                   d, genpd, &perf_state_fops);
+}
+
+static int __init genpd_debug_init(void)
+{
+       struct generic_pm_domain *genpd;
+
+       genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
+
+       debugfs_create_file("pm_genpd_summary", S_IRUGO, genpd_debugfs_dir,
+                           NULL, &summary_fops);
+
+       list_for_each_entry(genpd, &gpd_list, gpd_list_node)
+               genpd_debug_add(genpd);
+
+       return 0;
+}
+late_initcall(genpd_debug_init);
+
+static void __exit genpd_debug_exit(void)
+{
+       debugfs_remove_recursive(genpd_debugfs_dir);
+}
+__exitcall(genpd_debug_exit);
+#endif /* CONFIG_DEBUG_FS */
diff --git a/drivers/pmdomain/governor.c b/drivers/pmdomain/governor.c
new file mode 100644 (file)
index 0000000..d1a10ee
--- /dev/null
@@ -0,0 +1,418 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * drivers/base/power/domain_governor.c - Governors for device PM domains.
+ *
+ * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
+ */
+#include <linux/kernel.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_qos.h>
+#include <linux/hrtimer.h>
+#include <linux/cpuidle.h>
+#include <linux/cpumask.h>
+#include <linux/ktime.h>
+
+static int dev_update_qos_constraint(struct device *dev, void *data)
+{
+       s64 *constraint_ns_p = data;
+       s64 constraint_ns;
+
+       if (dev->power.subsys_data && dev->power.subsys_data->domain_data) {
+               struct gpd_timing_data *td = dev_gpd_data(dev)->td;
+
+               /*
+                * Only take suspend-time QoS constraints of devices into
+                * account, because constraints updated after the device has
+                * been suspended are not guaranteed to be taken into account
+                * anyway.  In order for them to take effect, the device has to
+                * be resumed and suspended again.
+                */
+               constraint_ns = td ? td->effective_constraint_ns :
+                               PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
+       } else {
+               /*
+                * The child is not in a domain and there's no info on its
+                * suspend/resume latencies, so assume them to be negligible and
+                * take its current PM QoS constraint (that's the only thing
+                * known at this point anyway).
+                */
+               constraint_ns = dev_pm_qos_read_value(dev, DEV_PM_QOS_RESUME_LATENCY);
+               constraint_ns *= NSEC_PER_USEC;
+       }
+
+       if (constraint_ns < *constraint_ns_p)
+               *constraint_ns_p = constraint_ns;
+
+       return 0;
+}
+
+/**
+ * default_suspend_ok - Default PM domain governor routine to suspend devices.
+ * @dev: Device to check.
+ *
+ * Returns: true if OK to suspend, false if not OK to suspend
+ */
+static bool default_suspend_ok(struct device *dev)
+{
+       struct gpd_timing_data *td = dev_gpd_data(dev)->td;
+       unsigned long flags;
+       s64 constraint_ns;
+
+       dev_dbg(dev, "%s()\n", __func__);
+
+       spin_lock_irqsave(&dev->power.lock, flags);
+
+       if (!td->constraint_changed) {
+               bool ret = td->cached_suspend_ok;
+
+               spin_unlock_irqrestore(&dev->power.lock, flags);
+               return ret;
+       }
+       td->constraint_changed = false;
+       td->cached_suspend_ok = false;
+       td->effective_constraint_ns = 0;
+       constraint_ns = __dev_pm_qos_resume_latency(dev);
+
+       spin_unlock_irqrestore(&dev->power.lock, flags);
+
+       if (constraint_ns == 0)
+               return false;
+
+       constraint_ns *= NSEC_PER_USEC;
+       /*
+        * We can walk the children without any additional locking, because
+        * they all have been suspended at this point and their
+        * effective_constraint_ns fields won't be modified in parallel with us.
+        */
+       if (!dev->power.ignore_children)
+               device_for_each_child(dev, &constraint_ns,
+                                     dev_update_qos_constraint);
+
+       if (constraint_ns == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS) {
+               /* "No restriction", so the device is allowed to suspend. */
+               td->effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
+               td->cached_suspend_ok = true;
+       } else if (constraint_ns == 0) {
+               /*
+                * This triggers if one of the children that don't belong to a
+                * domain has a zero PM QoS constraint and it's better not to
+                * suspend then.  effective_constraint_ns is zero already and
+                * cached_suspend_ok is false, so bail out.
+                */
+               return false;
+       } else {
+               constraint_ns -= td->suspend_latency_ns +
+                               td->resume_latency_ns;
+               /*
+                * effective_constraint_ns is zero already and cached_suspend_ok
+                * is false, so if the computed value is not positive, return
+                * right away.
+                */
+               if (constraint_ns <= 0)
+                       return false;
+
+               td->effective_constraint_ns = constraint_ns;
+               td->cached_suspend_ok = true;
+       }
+
+       /*
+        * The children have been suspended already, so we don't need to take
+        * their suspend latencies into account here.
+        */
+       return td->cached_suspend_ok;
+}
+
+static void update_domain_next_wakeup(struct generic_pm_domain *genpd, ktime_t now)
+{
+       ktime_t domain_wakeup = KTIME_MAX;
+       ktime_t next_wakeup;
+       struct pm_domain_data *pdd;
+       struct gpd_link *link;
+
+       if (!(genpd->flags & GENPD_FLAG_MIN_RESIDENCY))
+               return;
+
+       /*
+        * Devices that have a predictable wakeup pattern, may specify
+        * their next wakeup. Let's find the next wakeup from all the
+        * devices attached to this domain and from all the sub-domains.
+        * It is possible that component's a next wakeup may have become
+        * stale when we read that here. We will ignore to ensure the domain
+        * is able to enter its optimal idle state.
+        */
+       list_for_each_entry(pdd, &genpd->dev_list, list_node) {
+               next_wakeup = to_gpd_data(pdd)->td->next_wakeup;
+               if (next_wakeup != KTIME_MAX && !ktime_before(next_wakeup, now))
+                       if (ktime_before(next_wakeup, domain_wakeup))
+                               domain_wakeup = next_wakeup;
+       }
+
+       list_for_each_entry(link, &genpd->parent_links, parent_node) {
+               struct genpd_governor_data *cgd = link->child->gd;
+
+               next_wakeup = cgd ? cgd->next_wakeup : KTIME_MAX;
+               if (next_wakeup != KTIME_MAX && !ktime_before(next_wakeup, now))
+                       if (ktime_before(next_wakeup, domain_wakeup))
+                               domain_wakeup = next_wakeup;
+       }
+
+       genpd->gd->next_wakeup = domain_wakeup;
+}
+
+static bool next_wakeup_allows_state(struct generic_pm_domain *genpd,
+                                    unsigned int state, ktime_t now)
+{
+       ktime_t domain_wakeup = genpd->gd->next_wakeup;
+       s64 idle_time_ns, min_sleep_ns;
+
+       min_sleep_ns = genpd->states[state].power_off_latency_ns +
+                      genpd->states[state].residency_ns;
+
+       idle_time_ns = ktime_to_ns(ktime_sub(domain_wakeup, now));
+
+       return idle_time_ns >= min_sleep_ns;
+}
+
+static bool __default_power_down_ok(struct dev_pm_domain *pd,
+                                    unsigned int state)
+{
+       struct generic_pm_domain *genpd = pd_to_genpd(pd);
+       struct gpd_link *link;
+       struct pm_domain_data *pdd;
+       s64 min_off_time_ns;
+       s64 off_on_time_ns;
+
+       off_on_time_ns = genpd->states[state].power_off_latency_ns +
+               genpd->states[state].power_on_latency_ns;
+
+       min_off_time_ns = -1;
+       /*
+        * Check if subdomains can be off for enough time.
+        *
+        * All subdomains have been powered off already at this point.
+        */
+       list_for_each_entry(link, &genpd->parent_links, parent_node) {
+               struct genpd_governor_data *cgd = link->child->gd;
+
+               s64 sd_max_off_ns = cgd ? cgd->max_off_time_ns : -1;
+
+               if (sd_max_off_ns < 0)
+                       continue;
+
+               /*
+                * Check if the subdomain is allowed to be off long enough for
+                * the current domain to turn off and on (that's how much time
+                * it will have to wait worst case).
+                */
+               if (sd_max_off_ns <= off_on_time_ns)
+                       return false;
+
+               if (min_off_time_ns > sd_max_off_ns || min_off_time_ns < 0)
+                       min_off_time_ns = sd_max_off_ns;
+       }
+
+       /*
+        * Check if the devices in the domain can be off enough time.
+        */
+       list_for_each_entry(pdd, &genpd->dev_list, list_node) {
+               struct gpd_timing_data *td;
+               s64 constraint_ns;
+
+               /*
+                * Check if the device is allowed to be off long enough for the
+                * domain to turn off and on (that's how much time it will
+                * have to wait worst case).
+                */
+               td = to_gpd_data(pdd)->td;
+               constraint_ns = td->effective_constraint_ns;
+               /*
+                * Zero means "no suspend at all" and this runs only when all
+                * devices in the domain are suspended, so it must be positive.
+                */
+               if (constraint_ns == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS)
+                       continue;
+
+               if (constraint_ns <= off_on_time_ns)
+                       return false;
+
+               if (min_off_time_ns > constraint_ns || min_off_time_ns < 0)
+                       min_off_time_ns = constraint_ns;
+       }
+
+       /*
+        * If the computed minimum device off time is negative, there are no
+        * latency constraints, so the domain can spend arbitrary time in the
+        * "off" state.
+        */
+       if (min_off_time_ns < 0)
+               return true;
+
+       /*
+        * The difference between the computed minimum subdomain or device off
+        * time and the time needed to turn the domain on is the maximum
+        * theoretical time this domain can spend in the "off" state.
+        */
+       genpd->gd->max_off_time_ns = min_off_time_ns -
+               genpd->states[state].power_on_latency_ns;
+       return true;
+}
+
+/**
+ * _default_power_down_ok - Default generic PM domain power off governor routine.
+ * @pd: PM domain to check.
+ * @now: current ktime.
+ *
+ * This routine must be executed under the PM domain's lock.
+ *
+ * Returns: true if OK to power down, false if not OK to power down
+ */
+static bool _default_power_down_ok(struct dev_pm_domain *pd, ktime_t now)
+{
+       struct generic_pm_domain *genpd = pd_to_genpd(pd);
+       struct genpd_governor_data *gd = genpd->gd;
+       int state_idx = genpd->state_count - 1;
+       struct gpd_link *link;
+
+       /*
+        * Find the next wakeup from devices that can determine their own wakeup
+        * to find when the domain would wakeup and do it for every device down
+        * the hierarchy. It is not worth while to sleep if the state's residency
+        * cannot be met.
+        */
+       update_domain_next_wakeup(genpd, now);
+       if ((genpd->flags & GENPD_FLAG_MIN_RESIDENCY) && (gd->next_wakeup != KTIME_MAX)) {
+               /* Let's find out the deepest domain idle state, the devices prefer */
+               while (state_idx >= 0) {
+                       if (next_wakeup_allows_state(genpd, state_idx, now)) {
+                               gd->max_off_time_changed = true;
+                               break;
+                       }
+                       state_idx--;
+               }
+
+               if (state_idx < 0) {
+                       state_idx = 0;
+                       gd->cached_power_down_ok = false;
+                       goto done;
+               }
+       }
+
+       if (!gd->max_off_time_changed) {
+               genpd->state_idx = gd->cached_power_down_state_idx;
+               return gd->cached_power_down_ok;
+       }
+
+       /*
+        * We have to invalidate the cached results for the parents, so
+        * use the observation that default_power_down_ok() is not
+        * going to be called for any parent until this instance
+        * returns.
+        */
+       list_for_each_entry(link, &genpd->child_links, child_node) {
+               struct genpd_governor_data *pgd = link->parent->gd;
+
+               if (pgd)
+                       pgd->max_off_time_changed = true;
+       }
+
+       gd->max_off_time_ns = -1;
+       gd->max_off_time_changed = false;
+       gd->cached_power_down_ok = true;
+
+       /*
+        * Find a state to power down to, starting from the state
+        * determined by the next wakeup.
+        */
+       while (!__default_power_down_ok(pd, state_idx)) {
+               if (state_idx == 0) {
+                       gd->cached_power_down_ok = false;
+                       break;
+               }
+               state_idx--;
+       }
+
+done:
+       genpd->state_idx = state_idx;
+       gd->cached_power_down_state_idx = genpd->state_idx;
+       return gd->cached_power_down_ok;
+}
+
+static bool default_power_down_ok(struct dev_pm_domain *pd)
+{
+       return _default_power_down_ok(pd, ktime_get());
+}
+
+#ifdef CONFIG_CPU_IDLE
+static bool cpu_power_down_ok(struct dev_pm_domain *pd)
+{
+       struct generic_pm_domain *genpd = pd_to_genpd(pd);
+       struct cpuidle_device *dev;
+       ktime_t domain_wakeup, next_hrtimer;
+       ktime_t now = ktime_get();
+       s64 idle_duration_ns;
+       int cpu, i;
+
+       /* Validate dev PM QoS constraints. */
+       if (!_default_power_down_ok(pd, now))
+               return false;
+
+       if (!(genpd->flags & GENPD_FLAG_CPU_DOMAIN))
+               return true;
+
+       /*
+        * Find the next wakeup for any of the online CPUs within the PM domain
+        * and its subdomains. Note, we only need the genpd->cpus, as it already
+        * contains a mask of all CPUs from subdomains.
+        */
+       domain_wakeup = ktime_set(KTIME_SEC_MAX, 0);
+       for_each_cpu_and(cpu, genpd->cpus, cpu_online_mask) {
+               dev = per_cpu(cpuidle_devices, cpu);
+               if (dev) {
+                       next_hrtimer = READ_ONCE(dev->next_hrtimer);
+                       if (ktime_before(next_hrtimer, domain_wakeup))
+                               domain_wakeup = next_hrtimer;
+               }
+       }
+
+       /* The minimum idle duration is from now - until the next wakeup. */
+       idle_duration_ns = ktime_to_ns(ktime_sub(domain_wakeup, now));
+       if (idle_duration_ns <= 0)
+               return false;
+
+       /* Store the next domain_wakeup to allow consumers to use it. */
+       genpd->gd->next_hrtimer = domain_wakeup;
+
+       /*
+        * Find the deepest idle state that has its residency value satisfied
+        * and by also taking into account the power off latency for the state.
+        * Start at the state picked by the dev PM QoS constraint validation.
+        */
+       i = genpd->state_idx;
+       do {
+               if (idle_duration_ns >= (genpd->states[i].residency_ns +
+                   genpd->states[i].power_off_latency_ns)) {
+                       genpd->state_idx = i;
+                       return true;
+               }
+       } while (--i >= 0);
+
+       return false;
+}
+
+struct dev_power_governor pm_domain_cpu_gov = {
+       .suspend_ok = default_suspend_ok,
+       .power_down_ok = cpu_power_down_ok,
+};
+#endif
+
+struct dev_power_governor simple_qos_governor = {
+       .suspend_ok = default_suspend_ok,
+       .power_down_ok = default_power_down_ok,
+};
+
+/*
+ * pm_domain_always_on_gov - A governor implementing an always-on policy
+ */
+struct dev_power_governor pm_domain_always_on_gov = {
+       .suspend_ok = default_suspend_ok,
+};