[PATCH 5.15 802/917] ACPI: PM: Fix device wakeup power reference counting error

Greg Kroah-Hartman
2021-11-16T00:36:33Z

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

[ Upstream commit 452a3e723f75880757acf87b053935c43aa89f89 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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 4b42debeed455..c95eedd58f5bf 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -755,13 +755,11 @@ 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);
--
2.33.0