Revert "ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle"

Revert commit eed4d47efe95 (ACPI / sleep: Ignore spurious SCI wakeups
from suspend-to-idle) as it turned out to be premature and triggered
a number of different issues on various systems.

That includes, but is not limited to, premature suspend-to-RAM aborts
on Dell XPS 13 (9343) reported by Dominik.

The issue the commit in question attempted to address is real and
will need to be taken care of going forward, but evidently more work
is needed for this purpose.

Reported-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/battery.c

@@ -776,7 +776,7 @@ static int acpi_battery_update(struct acpi_battery *battery, bool resume)
 	if ((battery->state & ACPI_BATTERY_STATE_CRITICAL) ||
 	    (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
             (battery->capacity_now <= battery->alarm)))
-		pm_wakeup_hard_event(&battery->device->dev);
+		pm_wakeup_event(&battery->device->dev, 0);
 
 	return result;
 }

drivers/acpi/button.c

@@ -216,7 +216,7 @@ static int acpi_lid_notify_state(struct acpi_device *device, int state)
 	}
 
 	if (state)
-		pm_wakeup_hard_event(&device->dev);
+		pm_wakeup_event(&device->dev, 0);
 
 	ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, device);
 	if (ret == NOTIFY_DONE)
@@ -398,7 +398,7 @@ static void acpi_button_notify(struct acpi_device *device, u32 event)
 		} else {
 			int keycode;
 
-			pm_wakeup_hard_event(&device->dev);
+			pm_wakeup_event(&device->dev, 0);
 			if (button->suspended)
 				break;
 
@@ -530,7 +530,6 @@ static int acpi_button_add(struct acpi_device *device)
 		lid_device = device;
 	}
 
-	device_init_wakeup(&device->dev, true);
 	printk(KERN_INFO PREFIX "%s [%s]\n", name, acpi_device_bid(device));
 	return 0;
 

drivers/acpi/device_pm.c

@@ -24,7 +24,6 @@
 #include <linux/pm_qos.h>
 #include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
-#include <linux/suspend.h>
 
 #include "internal.h"
 
@@ -400,7 +399,7 @@ static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)
 	mutex_lock(&acpi_pm_notifier_lock);
 
 	if (adev->wakeup.flags.notifier_present) {
-		pm_wakeup_ws_event(adev->wakeup.ws, 0, true);
+		__pm_wakeup_event(adev->wakeup.ws, 0);
 		if (adev->wakeup.context.work.func)
 			queue_pm_work(&adev->wakeup.context.work);
 	}

drivers/acpi/sleep.c

@@ -662,40 +662,14 @@ static int acpi_freeze_prepare(void)
 	acpi_os_wait_events_complete();
 	if (acpi_sci_irq_valid())
 		enable_irq_wake(acpi_sci_irq);
-
 	return 0;
 }
 
-static void acpi_freeze_wake(void)
-{
-	/*
-	 * If IRQD_WAKEUP_ARMED is not set for the SCI at this point, it means
-	 * that the SCI has triggered while suspended, so cancel the wakeup in
-	 * case it has not been a wakeup event (the GPEs will be checked later).
-	 */
-	if (acpi_sci_irq_valid() &&
-	    !irqd_is_wakeup_armed(irq_get_irq_data(acpi_sci_irq)))
-		pm_system_cancel_wakeup();
-}
-
-static void acpi_freeze_sync(void)
-{
-	/*
-	 * Process all pending events in case there are any wakeup ones.
-	 *
-	 * The EC driver uses the system workqueue, so that one needs to be
-	 * flushed too.
-	 */
-	acpi_os_wait_events_complete();
-	flush_scheduled_work();
-}
-
 static void acpi_freeze_restore(void)
 {
 	acpi_disable_wakeup_devices(ACPI_STATE_S0);
 	if (acpi_sci_irq_valid())
 		disable_irq_wake(acpi_sci_irq);
-
 	acpi_enable_all_runtime_gpes();
 }
 
@@ -707,8 +681,6 @@ static void acpi_freeze_end(void)
 static const struct platform_freeze_ops acpi_freeze_ops = {
 	.begin = acpi_freeze_begin,
 	.prepare = acpi_freeze_prepare,
-	.wake = acpi_freeze_wake,
-	.sync = acpi_freeze_sync,
 	.restore = acpi_freeze_restore,
 	.end = acpi_freeze_end,
 };

drivers/base/power/main.c

@@ -1091,6 +1091,11 @@ static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool a
 	if (async_error)
 		goto Complete;
 
+	if (pm_wakeup_pending()) {
+		async_error = -EBUSY;
+		goto Complete;
+	}
+
 	if (dev->power.syscore || dev->power.direct_complete)
 		goto Complete;
 

drivers/base/power/wakeup.c

@@ -28,8 +28,8 @@ bool events_check_enabled __read_mostly;
 /* First wakeup IRQ seen by the kernel in the last cycle. */
 unsigned int pm_wakeup_irq __read_mostly;
 
-/* If greater than 0 and the system is suspending, terminate the suspend. */
-static atomic_t pm_abort_suspend __read_mostly;
+/* If set and the system is suspending, terminate the suspend. */
+static bool pm_abort_suspend __read_mostly;
 
 /*
  * Combined counters of registered wakeup events and wakeup events in progress.
@@ -855,26 +855,20 @@ bool pm_wakeup_pending(void)
 		pm_print_active_wakeup_sources();
 	}
 
-	return ret || atomic_read(&pm_abort_suspend) > 0;
+	return ret || pm_abort_suspend;
 }
 
 void pm_system_wakeup(void)
 {
-	atomic_inc(&pm_abort_suspend);
+	pm_abort_suspend = true;
 	freeze_wake();
 }
 EXPORT_SYMBOL_GPL(pm_system_wakeup);
 
-void pm_system_cancel_wakeup(void)
-{
-	atomic_dec(&pm_abort_suspend);
-}
-
-void pm_wakeup_clear(bool reset)
+void pm_wakeup_clear(void)
 {
+	pm_abort_suspend = false;
 	pm_wakeup_irq = 0;
-	if (reset)
-		atomic_set(&pm_abort_suspend, 0);
 }
 
 void pm_system_irq_wakeup(unsigned int irq_number)

include/linux/suspend.h

@@ -189,8 +189,6 @@ struct platform_suspend_ops {
 struct platform_freeze_ops {
 	int (*begin)(void);
 	int (*prepare)(void);
-	void (*wake)(void);
-	void (*sync)(void);
 	void (*restore)(void);
 	void (*end)(void);
 };
@@ -430,8 +428,7 @@ extern unsigned int pm_wakeup_irq;
 
 extern bool pm_wakeup_pending(void);
 extern void pm_system_wakeup(void);
-extern void pm_system_cancel_wakeup(void);
-extern void pm_wakeup_clear(bool reset);
+extern void pm_wakeup_clear(void);
 extern void pm_system_irq_wakeup(unsigned int irq_number);
 extern bool pm_get_wakeup_count(unsigned int *count, bool block);
 extern bool pm_save_wakeup_count(unsigned int count);
@@ -481,7 +478,7 @@ static inline int unregister_pm_notifier(struct notifier_block *nb)
 
 static inline bool pm_wakeup_pending(void) { return false; }
 static inline void pm_system_wakeup(void) {}
-static inline void pm_wakeup_clear(bool reset) {}
+static inline void pm_wakeup_clear(void) {}
 static inline void pm_system_irq_wakeup(unsigned int irq_number) {}
 
 static inline void lock_system_sleep(void) {}

kernel/power/process.c

@@ -132,7 +132,7 @@ int freeze_processes(void)
 	if (!pm_freezing)
 		atomic_inc(&system_freezing_cnt);
 
-	pm_wakeup_clear(true);
+	pm_wakeup_clear();
 	pr_info("Freezing user space processes ... ");
 	pm_freezing = true;
 	error = try_to_freeze_tasks(true);

kernel/power/suspend.c

@@ -72,8 +72,6 @@ static void freeze_begin(void)
 
 static void freeze_enter(void)
 {
-	trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_FREEZE, true);
-
 	spin_lock_irq(&suspend_freeze_lock);
 	if (pm_wakeup_pending())
 		goto out;
@@ -100,27 +98,6 @@ static void freeze_enter(void)
  out:
 	suspend_freeze_state = FREEZE_STATE_NONE;
 	spin_unlock_irq(&suspend_freeze_lock);
-
-	trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_FREEZE, false);
-}
-
-static void s2idle_loop(void)
-{
-	do {
-		freeze_enter();
-
-		if (freeze_ops && freeze_ops->wake)
-			freeze_ops->wake();
-
-		dpm_resume_noirq(PMSG_RESUME);
-		if (freeze_ops && freeze_ops->sync)
-			freeze_ops->sync();
-
-		if (pm_wakeup_pending())
-			break;
-
-		pm_wakeup_clear(false);
-	} while (!dpm_suspend_noirq(PMSG_SUSPEND));
 }
 
 void freeze_wake(void)
@@ -394,8 +371,10 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
 	 * all the devices are suspended.
 	 */
 	if (state == PM_SUSPEND_FREEZE) {
-		s2idle_loop();
-		goto Platform_early_resume;
+		trace_suspend_resume(TPS("machine_suspend"), state, true);
+		freeze_enter();
+		trace_suspend_resume(TPS("machine_suspend"), state, false);
+		goto Platform_wake;
 	}
 
 	error = disable_nonboot_cpus();