From: Rafael J. Wysocki Date: Wed, 19 Nov 2014 00:44:11 +0000 (+0100) Subject: ACPI / PM: Ignore wakeup setting if the ACPI companion can't wake up X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=78579b7c7eb45f0e7ec5e9437087ed21749f9a9c;p=openwrt%2Fstaging%2Fblogic.git ACPI / PM: Ignore wakeup setting if the ACPI companion can't wake up As reported by Dmitry, on some Chromebooks there are devices with corresponding ACPI objects and with unusual system wakeup configuration. Namely, they technically are wakeup-capable, but the wakeup is handled via a platform-specific out-of-band mechanism and the ACPI PM layer has no information on the wakeup capability. As a result, device_may_wakeup(dev) called from acpi_dev_suspend_late() returns 'true' for those devices, but the wakeup.flags.valid flag is unset for the corresponding ACPI device objects, so acpi_device_wakeup() reproducibly fails for them causing acpi_dev_suspend_late() to return an error code. The entire system suspend is then aborted and the machines in question cannot suspend at all. Address the problem by ignoring the device_may_wakeup(dev) return value in acpi_dev_suspend_late() if the ACPI companion of the device being handled has wakeup.flags.valid unset (in which case it is clear that the wakeup is supposed to be handled by other means). This fixes a regression introduced by commit a76e9bd89ae7 (i2c: attach/detach I2C client device to the ACPI power domain) as the affected systems could suspend and resume successfully before that commit. Fixes: a76e9bd89ae7 (i2c: attach/detach I2C client device to the ACPI power domain) Reported-by: Dmitry Torokhov Reviewed-by: Dmitry Torokhov Cc: 3.13+ # 3.13+ Signed-off-by: Rafael J. Wysocki --- diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index 143ec6ea1468..7db193160766 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -878,7 +878,7 @@ int acpi_dev_suspend_late(struct device *dev) return 0; target_state = acpi_target_system_state(); - wakeup = device_may_wakeup(dev); + wakeup = device_may_wakeup(dev) && acpi_device_can_wakeup(adev); error = acpi_device_wakeup(adev, target_state, wakeup); if (wakeup && error) return error;