From 452a3e723f75880757acf87b053935c43aa89f89 Mon Sep 17 00:00:00 2001

From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>

Date: Thu, 4 Nov 2021 22:54:17 +0100

Subject: [PATCH] ACPI: PM: Fix device wakeup power reference counting error

Git-commit: 452a3e723f75880757acf87b053935c43aa89f89

Patch-mainline: v5.16-rc1

References: git-fixes stable-5.14.19

Fix a device wakeup power reference counting error introduced by

commit a2d7b2e004af ("ACPI: PM: Fix sharing of wakeup power

resources") because of a coding mistake.

Fixes: a2d7b2e004af ("ACPI: PM: Fix sharing of wakeup power resources")

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Acked-by: Takashi Iwai <tiwai@suse.de>

---

 drivers/acpi/power.c | 8 +++-----

 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c

index 112256154880..5dcb02ededbc 100644

--- a/drivers/acpi/power.c

+++ b/drivers/acpi/power.c

@@ -757,13 +757,11 @@ int acpi_disable_wakeup_device_power(struct acpi_device *dev)

 	mutex_lock(&acpi_device_lock);

-	if (dev->wakeup.prepare_count > 1) {

-		dev->wakeup.prepare_count--;

+	/* Do nothing if wakeup power has not been enabled for this device. */

+	if (dev->wakeup.prepare_count <= 0)

 		goto out;

-	}

-	/* Do nothing if wakeup power has not been enabled for this device. */

-	if (!dev->wakeup.prepare_count)

+	if (--dev->wakeup.prepare_count > 0)

 		goto out;

 	err = acpi_device_sleep_wake(dev, 0, 0, 0);

-- 

2.26.2