ACPI / PM: Add function for device power state initialization

Add function acpi_bus_init_power() for getting the initial power
state of an ACPI device and reference counting its power resources
as appropriate.

Make acpi_bus_get_power_flags() use the new function instead of
acpi_bus_get_power() that updates device->power.state without
reference counting the device's power resources.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Rafael J. Wysocki 2010-11-25 00:08:36 +01:00 committed by Len Brown
parent 5e6d4fe429
commit ade3e7fef7
3 changed files with 27 additions and 4 deletions

View file

@ -364,6 +364,31 @@ int acpi_bus_set_power(acpi_handle handle, int state)
EXPORT_SYMBOL(acpi_bus_set_power);
int acpi_bus_init_power(struct acpi_device *device)
{
int state;
int result;
if (!device)
return -EINVAL;
device->power.state = ACPI_STATE_UNKNOWN;
result = __acpi_bus_get_power(device, &state);
if (result)
return result;
if (device->power.flags.power_resources)
result = acpi_power_on_resources(device, state);
if (!result)
device->power.state = state;
return result;
}
bool acpi_bus_power_manageable(acpi_handle handle)
{
struct acpi_device *device;

View file

@ -44,6 +44,7 @@ int acpi_device_sleep_wake(struct acpi_device *dev,
int acpi_power_get_inferred_state(struct acpi_device *device, int *state);
int acpi_power_on_resources(struct acpi_device *device, int state);
int acpi_power_transition(struct acpi_device *device, int state);
int acpi_bus_init_power(struct acpi_device *device);
extern int acpi_power_nocheck;
int acpi_wakeup_device_init(void);

View file

@ -901,10 +901,7 @@ static int acpi_bus_get_power_flags(struct acpi_device *device)
device->power.states[ACPI_STATE_D3].flags.valid = 1;
device->power.states[ACPI_STATE_D3].power = 0;
/* TBD: System wake support and resource requirements. */
device->power.state = ACPI_STATE_UNKNOWN;
acpi_bus_get_power(device->handle, &(device->power.state));
acpi_bus_init_power(device);
return 0;
}