diff options
Diffstat (limited to 'drivers/acpi/device_pm.c')
| -rw-r--r-- | drivers/acpi/device_pm.c | 30 |
1 files changed, 26 insertions, 4 deletions
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index bc493aa3af19..31c217a42839 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -278,16 +278,38 @@ 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; } +/** + * acpi_device_fix_up_power - Force device with missing _PSC into D0. + * @device: Device object whose power state is to be fixed up. + * + * Devices without power resources and _PSC, but having _PS0 and _PS3 defined, + * are assumed to be put into D0 by the BIOS. However, in some cases that may + * not be the case and this function should be used then. + */ +int acpi_device_fix_up_power(struct acpi_device *device) +{ + int ret = 0; + + if (!device->power.flags.power_resources + && !device->power.flags.explicit_get + && device->power.state == ACPI_STATE_D0) + ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0); + + return ret; +} + int acpi_bus_update_power(acpi_handle handle, int *state_p) { struct acpi_device *device; |