/**
* acpi_dev_pm_low_power - Put ACPI device into a low-power state.
* @dev: Device to put into a low-power state.
* @adev: ACPI device node corresponding to @dev.
* @system_state: System state to choose the device state for.
*/
static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
u32 system_state)
{
int ret, state;
if (!acpi_device_power_manageable(adev))
return 0;
ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state);
return ret ? ret : acpi_device_set_power(adev, state);
}
/**
* acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
* @dev: Device whose preferred target power state to return.
* @d_min_p: Location to store the upper limit of the allowed states range.
* @d_max_in: Deepest low-power state to take into consideration.
* Return value: Preferred power state of the device on success, -ENODEV
* if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
* incorrect, or -ENODATA on ACPI method failure.
*
* The caller must ensure that @dev is valid before using this function.
*/
int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
{
struct acpi_device *adev;
int ret, d_min, d_max;
if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
return -EINVAL;
if (d_max_in > ACPI_STATE_D3_HOT) {
enum pm_qos_flags_status stat;
stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
if (stat == PM_QOS_FLAGS_ALL)
d_max_in = ACPI_STATE_D3_HOT;
}
adev = ACPI_COMPANION(dev);
if (!adev) {
dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
return -ENODEV;
}
ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(),
&d_min, &d_max);
if (ret)
return ret;
if (d_max_in < d_min)
return -EINVAL;
if (d_max > d_max_in) {
for (d_max = d_max_in; d_max > d_min; d_max--) {
if (adev->power.states[d_max].flags.valid)
break;
}
}
if (d_min_p)
*d_min_p = d_min;
return d_max;
}
/**
* acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
* @dev: Device whose preferred target power state to return.
* @d_min_p: Location to store the upper limit of the allowed states range.
* @d_max_in: Deepest low-power state to take into consideration.
* Return value: Preferred power state of the device on success, -ENODEV
* if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
* incorrect, or -ENODATA on ACPI method failure.
*
* The caller must ensure that @dev is valid before using this function.
*/
int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
{
acpi_handle handle = ACPI_HANDLE(dev);
struct acpi_device *adev;
int ret, d_min, d_max;
if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
return -EINVAL;
if (d_max_in > ACPI_STATE_D3_HOT) {
enum pm_qos_flags_status stat;
stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
if (stat == PM_QOS_FLAGS_ALL)
d_max_in = ACPI_STATE_D3_HOT;
}
if (!handle || acpi_bus_get_device(handle, &adev)) {
dev_dbg(dev, "ACPI handle without context in %s!\n", __func__);
return -ENODEV;
}
ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(),
&d_min, &d_max);
if (ret)
return ret;
if (d_max_in < d_min)
return -EINVAL;
if (d_max > d_max_in) {
for (d_max = d_max_in; d_max > d_min; d_max--) {
if (adev->power.states[d_max].flags.valid)
break;
}
}
if (d_min_p)
*d_min_p = d_min;
return d_max;
}
/**
* acpi_subsys_prepare - Prepare device for system transition to a sleep state.
* @dev: Device to prepare.
*/
int acpi_subsys_prepare(struct device *dev)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
u32 sys_target;
int ret, state;
ret = pm_generic_prepare(dev);
if (ret < 0)
return ret;
if (!adev || !pm_runtime_suspended(dev)
|| device_may_wakeup(dev) != !!adev->wakeup.prepare_count)
return 0;
sys_target = acpi_target_system_state();
if (sys_target == ACPI_STATE_S0)
return 1;
if (adev->power.flags.dsw_present)
return 0;
ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
return !ret && state == adev->power.state;
}
