ACPI: s2idle: Add a new ->check() callback for platform_s2idle_ops

On some platforms it is found that Linux more aggressively enters s2idle
than Windows enters Modern Standby and this uncovers some synchronization
issues for the platform.  To aid in debugging this class of problems in
the future, add support for an extra optional callback intended for
drivers to emit extra debugging.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20220829162953.5947-2-mario.limonciello@amd.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

diff --git a/drivers/acpi/sleep.h b/drivers/acpi/sleep.h
index 7fe41ee489d6123c2fec04a6672ef25f1c04cbce..d960a238be4e51de7f7fdb34906e1835360ccc22 100644 (file)
--- a/drivers/acpi/sleep.h
+++ b/drivers/acpi/sleep.h
@@ -18,6 +18,7 @@ static inline acpi_status acpi_set_waking_vector(u32 wakeup_address)
 extern int acpi_s2idle_begin(void);
 extern int acpi_s2idle_prepare(void);
 extern int acpi_s2idle_prepare_late(void);
+extern void acpi_s2idle_check(void);
 extern bool acpi_s2idle_wake(void);
 extern void acpi_s2idle_restore_early(void);
 extern void acpi_s2idle_restore(void);

diff --git a/drivers/acpi/x86/s2idle.c b/drivers/acpi/x86/s2idle.c
index f9ac12b778e6a311183fd1ec7068e2bc61f608d9..474aa46f82f6065f16dc2bb8bcccae02339aa9dd 100644 (file)
--- a/drivers/acpi/x86/s2idle.c
+++ b/drivers/acpi/x86/s2idle.c
@@ -486,6 +486,19 @@ int acpi_s2idle_prepare_late(void)
        return 0;
 }
 
+void acpi_s2idle_check(void)
+{
+       struct acpi_s2idle_dev_ops *handler;
+
+       if (!lps0_device_handle || sleep_no_lps0)
+               return;
+
+       list_for_each_entry(handler, &lps0_s2idle_devops_head, list_node) {
+               if (handler->check)
+                       handler->check();
+       }
+}
+
 void acpi_s2idle_restore_early(void)
 {
        struct acpi_s2idle_dev_ops *handler;
@@ -527,6 +540,7 @@ static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = {
        .begin = acpi_s2idle_begin,
        .prepare = acpi_s2idle_prepare,
        .prepare_late = acpi_s2idle_prepare_late,
+       .check = acpi_s2idle_check,
        .wake = acpi_s2idle_wake,
        .restore_early = acpi_s2idle_restore_early,
        .restore = acpi_s2idle_restore,

diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 6f64b2f3dc547951b2635beb1e6a11dbd033cbee..acaa2ddc067d3616df8f9fc9cc0f42728362c71f 100644 (file)
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1075,6 +1075,7 @@ acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state,
 struct acpi_s2idle_dev_ops {
        struct list_head list_node;
        void (*prepare)(void);
+       void (*check)(void);
        void (*restore)(void);
 };
 int acpi_register_lps0_dev(struct acpi_s2idle_dev_ops *arg);

diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 70f2921e2e703248944bda50a2e2b5951d743ef7..03ed42ed2c7f62608cd9853cdb207ac086d49cd3 100644 (file)
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -191,6 +191,7 @@ struct platform_s2idle_ops {
        int (*begin)(void);
        int (*prepare)(void);
        int (*prepare_late)(void);
+       void (*check)(void);
        bool (*wake)(void);
        void (*restore_early)(void);
        void (*restore)(void);

diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 827075944d28357950b3bf55ec22d53987bbd920..c6272d466e58e37ad54a14c44b7a5d6387ca1cff 100644 (file)
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -136,6 +136,9 @@ static void s2idle_loop(void)
                        break;
                }
 
+               if (s2idle_ops && s2idle_ops->check)
+                       s2idle_ops->check();
+
                s2idle_enter();
        }