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