| From 7cd8407d53ef5fb0280fcbe34f42311472f90feb Mon Sep 17 00:00:00 2001 |
| From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> |
| Date: Wed, 5 Jun 2013 14:01:19 +0200 |
| Subject: ACPI / PM: Do not execute _PS0 for devices without _PSC during initialization |
| |
| From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> |
| |
| commit 7cd8407d53ef5fb0280fcbe34f42311472f90feb upstream. |
| |
| Commit b378549 (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> |
| Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/acpi/device_pm.c | 10 ++++++---- |
| 1 file changed, 6 insertions(+), 4 deletions(-) |
| |
| --- a/drivers/acpi/device_pm.c |
| +++ b/drivers/acpi/device_pm.c |
| @@ -269,11 +269,13 @@ int acpi_bus_init_power(struct acpi_devi |
| 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; |