regulator: event: Add regulator netlink event support
authorNaresh Solanki <naresh.solanki@9elements.com>
Tue, 5 Dec 2023 10:52:04 +0000 (16:22 +0530)
committerMark Brown <broonie@kernel.org>
Wed, 6 Dec 2023 13:14:54 +0000 (13:14 +0000)
This commit introduces netlink event support to the regulator subsystem.

Changes:
- Introduce event.c and regnl.h for netlink event handling.
- Implement reg_generate_netlink_event to broadcast regulator events.
- Update Makefile to include the new event.c file.

Signed-off-by: Naresh Solanki <naresh.solanki@9elements.com>
Link: https://lore.kernel.org/r/20231205105207.1262928-1-naresh.solanki@9elements.com
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/regulator/Kconfig
drivers/regulator/Makefile
drivers/regulator/core.c
drivers/regulator/event.c [new file with mode: 0644]
drivers/regulator/regnl.h [new file with mode: 0644]
include/linux/regulator/consumer.h
include/uapi/regulator/regulator.h [new file with mode: 0644]

index f3ec246913784643b1f435122b95bde598113ff1..550145f82726e95dd856d12a4f7d660f61a14500 100644 (file)
@@ -56,6 +56,16 @@ config REGULATOR_USERSPACE_CONSUMER
 
          If unsure, say no.
 
+config REGULATOR_NETLINK_EVENTS
+       bool "Enable support for receiving regulator events via netlink"
+       depends on NET
+       help
+         Enabling this option allows the kernel to broadcast regulator events using
+         the netlink mechanism. User-space applications can subscribe to these events
+         for real-time updates on various regulator events.
+
+         If unsure, say no.
+
 config REGULATOR_88PG86X
        tristate "Marvell 88PG86X voltage regulators"
        depends on I2C
index b2b059b5ee565a31ba5c3bd27aa51cc4b77523e1..46fb569e6be88c09439d1fbcd79869fa070caa0c 100644 (file)
@@ -5,6 +5,7 @@
 
 
 obj-$(CONFIG_REGULATOR) += core.o dummy.o fixed-helper.o helpers.o devres.o irq_helpers.o
+obj-$(CONFIG_REGULATOR_NETLINK_EVENTS) += event.o
 obj-$(CONFIG_OF) += of_regulator.o
 obj-$(CONFIG_REGULATOR_FIXED_VOLTAGE) += fixed.o
 obj-$(CONFIG_REGULATOR_VIRTUAL_CONSUMER) += virtual.o
index 4aa9ec8c22f38d711889385966b196cdfd4f11ef..a968dabb48f55742beed11dd14c90a3668e2c7b3 100644 (file)
@@ -33,6 +33,7 @@
 
 #include "dummy.h"
 #include "internal.h"
+#include "regnl.h"
 
 static DEFINE_WW_CLASS(regulator_ww_class);
 static DEFINE_MUTEX(regulator_nesting_mutex);
@@ -4854,7 +4855,23 @@ static int _notifier_call_chain(struct regulator_dev *rdev,
                                  unsigned long event, void *data)
 {
        /* call rdev chain first */
-       return blocking_notifier_call_chain(&rdev->notifier, event, data);
+       int ret =  blocking_notifier_call_chain(&rdev->notifier, event, data);
+
+       if (IS_REACHABLE(CONFIG_REGULATOR_NETLINK_EVENTS)) {
+               struct device *parent = rdev->dev.parent;
+               const char *rname = rdev_get_name(rdev);
+               char name[32];
+
+               /* Avoid duplicate debugfs directory names */
+               if (parent && rname == rdev->desc->name) {
+                       snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
+                                rname);
+                       rname = name;
+               }
+               reg_generate_netlink_event(rname, event);
+       }
+
+       return ret;
 }
 
 int _regulator_bulk_get(struct device *dev, int num_consumers,
diff --git a/drivers/regulator/event.c b/drivers/regulator/event.c
new file mode 100644 (file)
index 0000000..0ec58f3
--- /dev/null
@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Regulator event over netlink
+ *
+ * Author: Naresh Solanki <Naresh.Solanki@9elements.com>
+ */
+
+#include <regulator/regulator.h>
+#include <net/netlink.h>
+#include <net/genetlink.h>
+
+#include "regnl.h"
+
+static unsigned int reg_event_seqnum;
+
+static const struct genl_multicast_group reg_event_mcgrps[] = {
+       { .name = REG_GENL_MCAST_GROUP_NAME, },
+};
+
+static struct genl_family reg_event_genl_family __ro_after_init = {
+       .module = THIS_MODULE,
+       .name = REG_GENL_FAMILY_NAME,
+       .version = REG_GENL_VERSION,
+       .maxattr = REG_GENL_ATTR_MAX,
+       .mcgrps = reg_event_mcgrps,
+       .n_mcgrps = ARRAY_SIZE(reg_event_mcgrps),
+};
+
+int reg_generate_netlink_event(const char *reg_name, u64 event)
+{
+       struct sk_buff *skb;
+       struct nlattr *attr;
+       struct reg_genl_event *edata;
+       void *msg_header;
+       int size;
+
+       /* allocate memory */
+       size = nla_total_size(sizeof(struct reg_genl_event)) +
+           nla_total_size(0);
+
+       skb = genlmsg_new(size, GFP_ATOMIC);
+       if (!skb)
+               return -ENOMEM;
+
+       /* add the genetlink message header */
+       msg_header = genlmsg_put(skb, 0, reg_event_seqnum++,
+                                &reg_event_genl_family, 0,
+                                REG_GENL_CMD_EVENT);
+       if (!msg_header) {
+               nlmsg_free(skb);
+               return -ENOMEM;
+       }
+
+       /* fill the data */
+       attr = nla_reserve(skb, REG_GENL_ATTR_EVENT, sizeof(struct reg_genl_event));
+       if (!attr) {
+               nlmsg_free(skb);
+               return -EINVAL;
+       }
+
+       edata = nla_data(attr);
+       memset(edata, 0, sizeof(struct reg_genl_event));
+
+       strscpy(edata->reg_name, reg_name, sizeof(edata->reg_name));
+       edata->event = event;
+
+       /* send multicast genetlink message */
+       genlmsg_end(skb, msg_header);
+       size = genlmsg_multicast(&reg_event_genl_family, skb, 0, 0, GFP_ATOMIC);
+
+       return size;
+}
+
+static int __init reg_event_genetlink_init(void)
+{
+       return genl_register_family(&reg_event_genl_family);
+}
+
+static int __init reg_event_init(void)
+{
+       int error;
+
+       /* create genetlink for acpi event */
+       error = reg_event_genetlink_init();
+       if (error)
+               pr_warn("Failed to create genetlink family for reg event\n");
+
+       return 0;
+}
+
+fs_initcall(reg_event_init);
diff --git a/drivers/regulator/regnl.h b/drivers/regulator/regnl.h
new file mode 100644 (file)
index 0000000..bcba16c
--- /dev/null
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Regulator event over netlink
+ *
+ * Author: Naresh Solanki <Naresh.Solanki@9elements.com>
+ */
+
+#ifndef __REGULATOR_EVENT_H
+#define __REGULATOR_EVENT_H
+
+int reg_generate_netlink_event(const char *reg_name, u64 event);
+
+#endif
index 39b666b40ea61ea6aed4ac1025d74bdf67528a95..4660582a33022fc15946a811105318199ccaca42 100644 (file)
@@ -33,6 +33,7 @@
 
 #include <linux/err.h>
 #include <linux/suspend.h>
+#include <regulator/regulator.h>
 
 struct device;
 struct notifier_block;
@@ -84,52 +85,6 @@ struct regulator_dev;
 #define REGULATOR_MODE_IDLE                    0x4
 #define REGULATOR_MODE_STANDBY                 0x8
 
-/*
- * Regulator notifier events.
- *
- * UNDER_VOLTAGE  Regulator output is under voltage.
- * OVER_CURRENT   Regulator output current is too high.
- * REGULATION_OUT Regulator output is out of regulation.
- * FAIL           Regulator output has failed.
- * OVER_TEMP      Regulator over temp.
- * FORCE_DISABLE  Regulator forcibly shut down by software.
- * VOLTAGE_CHANGE Regulator voltage changed.
- *                Data passed is old voltage cast to (void *).
- * DISABLE        Regulator was disabled.
- * PRE_VOLTAGE_CHANGE   Regulator is about to have voltage changed.
- *                      Data passed is "struct pre_voltage_change_data"
- * ABORT_VOLTAGE_CHANGE Regulator voltage change failed for some reason.
- *                      Data passed is old voltage cast to (void *).
- * PRE_DISABLE    Regulator is about to be disabled
- * ABORT_DISABLE  Regulator disable failed for some reason
- *
- * NOTE: These events can be OR'ed together when passed into handler.
- */
-
-#define REGULATOR_EVENT_UNDER_VOLTAGE          0x01
-#define REGULATOR_EVENT_OVER_CURRENT           0x02
-#define REGULATOR_EVENT_REGULATION_OUT         0x04
-#define REGULATOR_EVENT_FAIL                   0x08
-#define REGULATOR_EVENT_OVER_TEMP              0x10
-#define REGULATOR_EVENT_FORCE_DISABLE          0x20
-#define REGULATOR_EVENT_VOLTAGE_CHANGE         0x40
-#define REGULATOR_EVENT_DISABLE                        0x80
-#define REGULATOR_EVENT_PRE_VOLTAGE_CHANGE     0x100
-#define REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE   0x200
-#define REGULATOR_EVENT_PRE_DISABLE            0x400
-#define REGULATOR_EVENT_ABORT_DISABLE          0x800
-#define REGULATOR_EVENT_ENABLE                 0x1000
-/*
- * Following notifications should be emitted only if detected condition
- * is such that the HW is likely to still be working but consumers should
- * take a recovery action to prevent problems esacalating into errors.
- */
-#define REGULATOR_EVENT_UNDER_VOLTAGE_WARN     0x2000
-#define REGULATOR_EVENT_OVER_CURRENT_WARN      0x4000
-#define REGULATOR_EVENT_OVER_VOLTAGE_WARN      0x8000
-#define REGULATOR_EVENT_OVER_TEMP_WARN         0x10000
-#define REGULATOR_EVENT_WARN_MASK              0x1E000
-
 /*
  * Regulator errors that can be queried using regulator_get_error_flags
  *
diff --git a/include/uapi/regulator/regulator.h b/include/uapi/regulator/regulator.h
new file mode 100644 (file)
index 0000000..d2b5612
--- /dev/null
@@ -0,0 +1,90 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Regulator uapi header
+ *
+ * Author: Naresh Solanki <Naresh.Solanki@9elements.com>
+ */
+
+#ifndef _UAPI_REGULATOR_H
+#define _UAPI_REGULATOR_H
+
+#ifdef __KERNEL__
+#include <linux/types.h>
+#else
+#include <stdint.h>
+#endif
+
+/*
+ * Regulator notifier events.
+ *
+ * UNDER_VOLTAGE  Regulator output is under voltage.
+ * OVER_CURRENT   Regulator output current is too high.
+ * REGULATION_OUT Regulator output is out of regulation.
+ * FAIL           Regulator output has failed.
+ * OVER_TEMP      Regulator over temp.
+ * FORCE_DISABLE  Regulator forcibly shut down by software.
+ * VOLTAGE_CHANGE Regulator voltage changed.
+ *                Data passed is old voltage cast to (void *).
+ * DISABLE        Regulator was disabled.
+ * PRE_VOLTAGE_CHANGE   Regulator is about to have voltage changed.
+ *                      Data passed is "struct pre_voltage_change_data"
+ * ABORT_VOLTAGE_CHANGE Regulator voltage change failed for some reason.
+ *                      Data passed is old voltage cast to (void *).
+ * PRE_DISABLE    Regulator is about to be disabled
+ * ABORT_DISABLE  Regulator disable failed for some reason
+ *
+ * NOTE: These events can be OR'ed together when passed into handler.
+ */
+
+#define REGULATOR_EVENT_UNDER_VOLTAGE          0x01
+#define REGULATOR_EVENT_OVER_CURRENT           0x02
+#define REGULATOR_EVENT_REGULATION_OUT         0x04
+#define REGULATOR_EVENT_FAIL                   0x08
+#define REGULATOR_EVENT_OVER_TEMP              0x10
+#define REGULATOR_EVENT_FORCE_DISABLE          0x20
+#define REGULATOR_EVENT_VOLTAGE_CHANGE         0x40
+#define REGULATOR_EVENT_DISABLE                        0x80
+#define REGULATOR_EVENT_PRE_VOLTAGE_CHANGE     0x100
+#define REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE   0x200
+#define REGULATOR_EVENT_PRE_DISABLE            0x400
+#define REGULATOR_EVENT_ABORT_DISABLE          0x800
+#define REGULATOR_EVENT_ENABLE                 0x1000
+/*
+ * Following notifications should be emitted only if detected condition
+ * is such that the HW is likely to still be working but consumers should
+ * take a recovery action to prevent problems esacalating into errors.
+ */
+#define REGULATOR_EVENT_UNDER_VOLTAGE_WARN     0x2000
+#define REGULATOR_EVENT_OVER_CURRENT_WARN      0x4000
+#define REGULATOR_EVENT_OVER_VOLTAGE_WARN      0x8000
+#define REGULATOR_EVENT_OVER_TEMP_WARN         0x10000
+#define REGULATOR_EVENT_WARN_MASK              0x1E000
+
+struct reg_genl_event {
+       char reg_name[32];
+       uint64_t event;
+};
+
+/* attributes of reg_genl_family */
+enum {
+       REG_GENL_ATTR_UNSPEC,
+       REG_GENL_ATTR_EVENT,    /* reg event info needed by user space */
+       __REG_GENL_ATTR_MAX,
+};
+
+#define REG_GENL_ATTR_MAX (__REG_GENL_ATTR_MAX - 1)
+
+/* commands supported by the reg_genl_family */
+enum {
+       REG_GENL_CMD_UNSPEC,
+       REG_GENL_CMD_EVENT,     /* kernel->user notifications for reg events */
+       __REG_GENL_CMD_MAX,
+};
+
+#define REG_GENL_CMD_MAX (__REG_GENL_CMD_MAX - 1)
+
+#define REG_GENL_FAMILY_NAME           "reg_event"
+#define REG_GENL_VERSION               0x01
+#define REG_GENL_MCAST_GROUP_NAME      "reg_mc_group"
+
+#endif /* _UAPI_REGULATOR_H */