Commit 7cd8407d authored Jun 05, 2013 by Rafael J. Wysocki

ACPI / PM: Do not execute _PS0 for devices without _PSC during initialization

Commit b3785492 (ACPI / PM: Do not power manage devices in unknown
initial states) added code to force devices without _PSC, but having
_PS0 defined in the ACPI namespace, into ACPI power state D0 by
executing _PS0 for them.  That turned out to break Toshiba P870-303,
however, so revert that code.

References: https://bugzilla.kernel.org/show_bug.cgi?id=58201


Reported-and-tested-by: Jerome Cantenot <jerome.cantenot@gmail.com>
Tracked-down-by: Lan Tianyu <tianyu.lan@intel.com>
Cc: 3.9+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

parent 9f29ab11

drivers/acpi/device_pm.c

+6 −4

Original line number	Diff line number	Diff line
		@@ -278,11 +278,13 @@ int acpi_bus_init_power(struct acpi_device *device)
		if (result)
		return result;
		} else if (state == ACPI_STATE_UNKNOWN) {
		/* No power resources and missing _PSC? Try to force D0. */
		/*
		* No power resources and missing _PSC? Cross fingers and make
		* it D0 in hope that this is what the BIOS put the device into.
		* [We tried to force D0 here by executing _PS0, but that broke
		* Toshiba P870-303 in a nasty way.]
		*/
		state = ACPI_STATE_D0;
		result = acpi_dev_pm_explicit_set(device, state);
		if (result)
		return result;
		}
		device->power.state = state;
		return 0;