int
acpi_power_transition (
struct acpi_device *device,
int state)
{
int result = 0;
struct acpi_handle_list *cl = NULL; /* Current Resources */
struct acpi_handle_list *tl = NULL; /* Target Resources */
int i = 0;
ACPI_FUNCTION_TRACE("acpi_power_transition");
if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
return_VALUE(-EINVAL);
if ((device->power.state < ACPI_STATE_D0) || (device->power.state > ACPI_STATE_D3))
return_VALUE(-ENODEV);
cl = &device->power.states[device->power.state].resources;
tl = &device->power.states[state].resources;
device->power.state = ACPI_STATE_UNKNOWN;
if (!cl->count && !tl->count) {
result = -ENODEV;
goto end;
}
/* TBD: Resources must be ordered. */
/*
* First we reference all power resources required in the target list
* (e.g. so the device doesn't loose power while transitioning).
*/
for (i=0; i<tl->count; i++) {
result = acpi_power_on(tl->handles[i]);
if (result)
goto end;
}
/*
* Then we dereference all power resources used in the current list.
*/
for (i=0; i<cl->count; i++) {
result = acpi_power_off_device(cl->handles[i]);
if (result)
goto end;
}
/* We shouldn't change the state till all above operations succeed */
device->power.state = state;
end:
if (result)
ACPI_DEBUG_PRINT((ACPI_DB_WARN,
"Error transitioning device [%s] to D%d\n",
device->pnp.bus_id, state));
return_VALUE(result);
}
int acpi_power_transition(struct acpi_device *device, int state)
{
int result = 0;
struct acpi_handle_list *cl = NULL; /* Current Resources */
struct acpi_handle_list *tl = NULL; /* Target Resources */
int i = 0;
if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
return -EINVAL;
if (device->power.state == state)
return 0;
if ((device->power.state < ACPI_STATE_D0)
|| (device->power.state > ACPI_STATE_D3))
return -ENODEV;
cl = &device->power.states[device->power.state].resources;
tl = &device->power.states[state].resources;
/* TBD: Resources must be ordered. */
/*
* First we reference all power resources required in the target list
* (e.g. so the device doesn't lose power while transitioning).
*/
for (i = 0; i < tl->count; i++) {
result = acpi_power_on(tl->handles[i]);
if (result)
goto end;
}
/*
* Then we dereference all power resources used in the current list.
*/
for (i = 0; i < cl->count; i++) {
result = acpi_power_off_device(cl->handles[i]);
if (result)
goto end;
}
end:
if (result)
device->power.state = ACPI_STATE_UNKNOWN;
else {
/* We shouldn't change the state till all above operations succeed */
device->power.state = state;
}
return result;
}
/*
* Shutdown a wakeup device, counterpart of above method
* 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
* State Wake) for the device, if present
* 2. Shutdown down the power resources
*/
int acpi_disable_wakeup_device_power(struct acpi_device *dev)
{
int i, err = 0;
if (!dev || !dev->wakeup.flags.valid)
return -EINVAL;
mutex_lock(&acpi_device_lock);
if (--dev->wakeup.prepare_count > 0)
goto out;
/*
* Executing the code below even if prepare_count is already zero when
* the function is called may be useful, for example for initialisation.
*/
if (dev->wakeup.prepare_count < 0)
dev->wakeup.prepare_count = 0;
err = acpi_device_sleep_wake(dev, 0, 0, 0);
if (err)
goto out;
/* Close power resource */
for (i = 0; i < dev->wakeup.resources.count; i++) {
int ret = acpi_power_off_device(
dev->wakeup.resources.handles[i]);
if (ret) {
printk(KERN_ERR PREFIX "Transition power state\n");
dev->wakeup.flags.valid = 0;
err = -ENODEV;
goto out;
}
}
out:
mutex_unlock(&acpi_device_lock);
return err;
}