- 根目录:
- drivers
- acpi
- device_pm.c
/*
* drivers/acpi/device_pm.c - ACPI device power management routines.
*
* Copyright (C) 2012, Intel Corp.
* Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#include <linux/acpi.h>
#include <linux/export.h>
#include <linux/mutex.h>
#include <linux/pm_qos.h>
#include <linux/pm_runtime.h>
#include "internal.h"
#define _COMPONENT ACPI_POWER_COMPONENT
ACPI_MODULE_NAME("device_pm");
/**
* acpi_power_state_string - String representation of ACPI device power state.
* @state: ACPI device power state to return the string representation of.
*/
const char *acpi_power_state_string(int state)
{
switch (state) {
case ACPI_STATE_D0:
return "D0";
case ACPI_STATE_D1:
return "D1";
case ACPI_STATE_D2:
return "D2";
case ACPI_STATE_D3_HOT:
return "D3hot";
case ACPI_STATE_D3_COLD:
return "D3cold";
default:
return "(unknown)";
}
}
/**
* acpi_device_get_power - Get power state of an ACPI device.
* @device: Device to get the power state of.
* @state: Place to store the power state of the device.
*
* This function does not update the device's power.state field, but it may
* update its parent's power.state field (when the parent's power state is
* unknown and the device's power state turns out to be D0).
*/
int acpi_device_get_power(struct acpi_device *device, int *state)
{
int result = ACPI_STATE_UNKNOWN;
if (!device || !state)
return -EINVAL;
if (!device->flags.power_manageable) {
/* TBD: Non-recursive algorithm for walking up hierarchy. */
*state = device->parent ?
device->parent->power.state : ACPI_STATE_D0;
goto out;
}
/*
* Get the device's power state from power resources settings and _PSC,
* if available.
*/
if (device->power.flags.power_resources) {
int error = acpi_power_get_inferred_state(device, &result);
if (error)
return error;
}
if (device->power.flags.explicit_get) {
acpi_handle handle = device->handle;
unsigned long long psc;
acpi_status status;
status = acpi_evaluate_integer(handle, "_PSC", NULL, &psc);
if (ACPI_FAILURE(status))
return -ENODEV;
/*
* The power resources settings may indicate a power state
* shallower than the actual power state of the device.
*
* Moreover, on systems predating ACPI 4.0, if the device
* doesn't depend on any power resources and _PSC returns 3,
* that means "power off". We need to maintain compatibility
* with those systems.
*/
if (psc > result && psc < ACPI_STATE_D3_COLD)
result = psc;
else if (result == ACPI_STATE_UNKNOWN)
result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_COLD : psc;
}
/*
* If we were unsure about the device parent's power state up to this
* point, the fact that the device is in D0 implies that the parent has
* to be in D0 too, except if ignore_parent is set.
*/
if (!device->power.flags.ignore_parent && device->parent
&& device->parent->power.state == ACPI_STATE_UNKNOWN
&& result == ACPI_STATE_D0)
device->parent->power.state = ACPI_STATE_D0;
*state = result;
out:
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
device->pnp.bus_id, acpi_power_state_string(*state)));
return 0;
}
static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)
{
if (adev->power.states[state].flags.explicit_set) {
char method[5] = { '_', 'P', 'S', '0' + state, '\0' };
acpi_status status;
status = acpi_evaluate_object(adev->handle, method, NULL, NULL);
if (ACPI_FAILURE(status))
return -ENODEV;
}
return 0;
}
/**
* acpi_device_set_power - Set power state of an ACPI device.
* @device: Device to set the power state of.
* @state: New power state to set.
*
* Callers must ensure that the device is power manageable before using this
* function.
*/
int acpi_device_set_power(struct acpi_device *device, int state)
{
int result = 0;
bool cut_power = false;
if (!device || !device->flags.power_manageable
|| (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
return -EINVAL;
/* Make sure this is a valid target state */
if (state == device->power.state) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n",
device->pnp.bus_id,
acpi_power_state_string(state)));
return 0;
}
if (!device->power.states[state].flags.valid) {
dev_warn(&device->dev, "Power state %s not supported\n",
acpi_power_state_string(state));
return -ENODEV;
}
if (!device->power.flags.ignore_parent &&
device->parent && (state < device->parent->power.state)) {
dev_warn(&device->dev,
"Cannot transition to power state %s for parent in %s\n",
acpi_power_state_string(state),
acpi_power_state_string(device->parent->power.state));
return -ENODEV;
}
/* For D3cold we should first transition into D3hot. */
if (state == ACPI_STATE_D3_COLD
&& device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible) {
state = ACPI_STATE_D3_HOT;
cut_power = true;
}
if (state < device->power.state && state != ACPI_STATE_D0
&& device->power.state >= ACPI_STATE_D3_HOT) {
dev_warn(&device->dev,
"Cannot transition to non-D0 state from D3\n");
return -ENODEV;
}
/*
* Transition Power
* ----------------
* In accordance with the ACPI specification first apply power (via
* power resources) and then evalute _PSx.
*/
if (device->power.flags.power_resources) {
result = acpi_power_transition(device, state);
if (result)
goto end;
}
result = acpi_dev_pm_explicit_set(device, state);
if (result)
goto end;
if (cut_power) {
device->power.state = state;
state = ACPI_STATE_D3_COLD;
result = acpi_power_transition(device, state);
}
end:
if (result) {
dev_warn(&device->dev, "Failed to change power state to %s\n",
acpi_power_state_string(state));
} else {
device->power.state = state;
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Device [%s] transitioned to %s\n",
device->pnp.bus_id,
acpi_power_state_string(state)));
}
return result;
}
EXPORT_SYMBOL(acpi_device_set_power);
int acpi_bus_set_power(acpi_handle handle, int state)
{
struct acpi_device *device;
int result;
result = acpi_bus_get_device(handle, &device);
if (result)
return result;
return acpi_device_set_power(device, 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;
if (!acpi_device_is_present(device))
return 0;
result = acpi_device_get_power(device, &state);
if (result)
return result;
if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
result = acpi_power_on_resources(device, state);
if (result)
return result;
result = acpi_dev_pm_explicit_set(device, state);
if (result)
return result;
} else if (state == ACPI_STATE_UNKNOWN) {
/*
* 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;
}
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_device_update_power(struct acpi_device *device, int *state_p)
{
int state;
int result;
if (device->power.state == ACPI_STATE_UNKNOWN) {
result = acpi_bus_init_power(device);
if (!result && state_p)
*state_p = device->power.state;
return result;
}
result = acpi_device_get_power(device, &state);
if (result)
return result;
if (state == ACPI_STATE_UNKNOWN) {
state = ACPI_STATE_D0;
result = acpi_device_set_power(device, state);
if (result)
return result;
} else {
if (device->power.flags.power_resources) {
/*
* We don't need to really switch the state, bu we need
* to update the power resources' reference counters.
*/
result = acpi_power_transition(device, state);
if (result)
return result;
}
device->power.state = state;
}
if (state_p)
*state_p = state;
return 0;
}
int acpi_bus_update_power(acpi_handle handle, int *state_p)
{
struct acpi_device *device;
int result;
result = acpi_bus_get_device(handle, &device);
return result ? result : acpi_device_update_power(device, state_p);
}
EXPORT_SYMBOL_GPL(acpi_bus_update_power);
bool acpi_bus_power_manageable(acpi_handle handle)
{
struct acpi_device *device;
int result;
result = acpi_bus_get_device(handle, &device);
return result ? false : device->flags.power_manageable;
}
EXPORT_SYMBOL(acpi_bus_power_manageable);
#ifdef CONFIG_PM
static DEFINE_MUTEX(acpi_pm_notifier_lock);
/**
* acpi_add_pm_notifier - Register PM notifier for given ACPI device.
* @adev: ACPI device to add the notifier for.
* @context: Context information to pass to the notifier routine.
*
* NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
* PM wakeup events. For example, wakeup events may be generated for bridges
* if one of the devices below the bridge is signaling wakeup, even if the
* bridge itself doesn't have a wakeup GPE associated with it.
*/
acpi_status acpi_add_pm_notifier(struct acpi_device *adev,
acpi_notify_handler handler, void *context)
{
acpi_status status = AE_ALREADY_EXISTS;
mutex_lock(&acpi_pm_notifier_lock);
if (adev->wakeup.flags.notifier_present)
goto out;
status = acpi_install_notify_handler(adev->handle,
ACPI_SYSTEM_NOTIFY,
handler, context);
if (ACPI_FAILURE(status))
goto out;
adev->wakeup.flags.notifier_present = true;
out:
mutex_unlock(&acpi_pm_notifier_lock);
return status;
}
/**
* acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
* @adev: ACPI device to remove the notifier from.
*/
acpi_status acpi_remove_pm_notifier(struct acpi_device *adev,
acpi_notify_handler handler)
{
acpi_status status = AE_BAD_PARAMETER;
mutex_lock(&acpi_pm_notifier_lock);
if (!adev->wakeup.flags.notifier_present)
goto out;
status = acpi_remove_notify_handler(adev->handle,
ACPI_SYSTEM_NOTIFY,
handler);
if (ACPI_FAILURE(status))
goto out;
adev->wakeup.flags.notifier_present = false;
out:
mutex_unlock(&acpi_pm_notifier_lock);
return status;
}
bool acpi_bus_can_wakeup(acpi_handle handle)
{
struct acpi_device *device;
int result;
result = acpi_bus_get_device(handle, &device);
return result ? false : device->wakeup.flags.valid;
}
EXPORT_SYMBOL(acpi_bus_can_wakeup);
/**
* acpi_dev_pm_get_state - Get preferred power state of ACPI device.
* @dev: Device whose preferred target power state to return.
* @adev: ACPI device node corresponding to @dev.
* @target_state: System state to match the resultant device state.
* @d_min_p: Location to store the highest power state available to the device.
* @d_max_p: Location to store the lowest power state available to the device.
*
* Find the lowest power (highest number) and highest power (lowest number) ACPI
* device power states that the device can be in while the system is in the
* state represented by @target_state. Store the integer numbers representing
* those stats in the memory locations pointed to by @d_max_p and @d_min_p,
* respectively.
*
* Callers must ensure that @dev and @adev are valid pointers and that @adev
* actually corresponds to @dev before using this function.
*
* Returns 0 on success or -ENODATA when one of the ACPI methods fails or
* returns a value that doesn't make sense. The memory locations pointed to by
* @d_max_p and @d_min_p are only modified on success.
*/
static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
u32 target_state, int *d_min_p, int *d_max_p)
{
char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };
acpi_handle handle = adev->handle;
unsigned long long ret;
int d_min, d_max;
bool wakeup = false;
acpi_status status;
/*
* If the system state is S0, the lowest power state the device can be
* in is D3cold, unless the device has _S0W and is supposed to signal
* wakeup, in which case the return value of _S0W has to be used as the
* lowest power state available to the device.
*/
d_min = ACPI_STATE_D0;
d_max = ACPI_STATE_D3_COLD;
/*
* If present, _SxD methods return the minimum D-state (highest power
* state) we can use for the corresponding S-states. Otherwise, the
* minimum D-state is D0 (ACPI 3.x).
*/
if (target_state > ACPI_STATE_S0) {
/*
* We rely on acpi_evaluate_integer() not clobbering the integer
* provided if AE_NOT_FOUND is returned.
*/
ret = d_min;
status = acpi_evaluate_integer(handle, method, NULL, &ret);
if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND)
|| ret > ACPI_STATE_D3_COLD)
return -ENODATA;
/*
* We need to handle legacy systems where D3hot and D3cold are
* the same and 3 is returned in both cases, so fall back to
* D3cold if D3hot is not a valid state.
*/
if (!adev->power.states[ret].flags.valid) {
if (ret == ACPI_STATE_D3_HOT)
ret = ACPI_STATE_D3_COLD;
else
return -ENODATA;
}
d_min = ret;
wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
&& adev->wakeup.sleep_state >= target_state;
} else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) !=
PM_QOS_FLAGS_NONE) {
wakeup = adev->wakeup.flags.valid;
}
/*
* If _PRW says we can wake up the system from the target sleep state,
* the D-state returned by _SxD is sufficient for that (we assume a
* wakeup-aware driver if wake is set). Still, if _SxW exists
* (ACPI 3.x), it should return the maximum (lowest power) D-state that
* can wake the system. _S0W may be valid, too.
*/
if (wakeup) {
method[3] = 'W';
status = acpi_evaluate_integer(handle, method, NULL, &ret);
if (status == AE_NOT_FOUND) {
if (target_state > ACPI_STATE_S0)
d_max = d_min;
} else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) {
/* Fall back to D3cold if ret is not a valid state. */
if (!adev->power.states[ret].flags.valid)
ret = ACPI_STATE_D3_COLD;
d_max = ret > d_min ? ret : d_min;
} else {
return -ENODATA;
}
}
if (d_min_p)
*d_min_p = d_min;
if (d_max_p)
*d_max_p = d_max;
return 0;
}
/**
* 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;
}
EXPORT_SYMBOL(acpi_pm_device_sleep_state);
#ifdef CONFIG_PM_RUNTIME
/**
* acpi_wakeup_device - Wakeup notification handler for ACPI devices.
* @handle: ACPI handle of the device the notification is for.
* @event: Type of the signaled event.
* @context: Device corresponding to @handle.
*/
static void acpi_wakeup_device(acpi_handle handle, u32 event, void *context)
{
struct device *dev = context;
if (event == ACPI_NOTIFY_DEVICE_WAKE && dev) {
pm_wakeup_event(dev, 0);
pm_runtime_resume(dev);
}
}
/**
* __acpi_device_run_wake - Enable/disable runtime remote wakeup for device.
* @adev: ACPI device to enable/disable the remote wakeup for.
* @enable: Whether to enable or disable the wakeup functionality.
*
* Enable/disable the GPE associated with @adev so that it can generate
* wakeup signals for the device in response to external (remote) events and
* enable/disable device wakeup power.
*
* Callers must ensure that @adev is a valid ACPI device node before executing
* this function.
*/
int __acpi_device_run_wake(struct acpi_device *adev, bool enable)
{
struct acpi_device_wakeup *wakeup = &adev->wakeup;
if (enable) {
acpi_status res;
int error;
error = acpi_enable_wakeup_device_power(adev, ACPI_STATE_S0);
if (error)
return error;
res = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
if (ACPI_FAILURE(res)) {
acpi_disable_wakeup_device_power(adev);
return -EIO;
}
} else {
acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
acpi_disable_wakeup_device_power(adev);
}
return 0;
}
/**
* acpi_pm_device_run_wake - Enable/disable remote wakeup for given device.
* @dev: Device to enable/disable the platform to wake up.
* @enable: Whether to enable or disable the wakeup functionality.
*/
int acpi_pm_device_run_wake(struct device *phys_dev, bool enable)
{
struct acpi_device *adev;
acpi_handle handle;
if (!device_run_wake(phys_dev))
return -EINVAL;
handle = ACPI_HANDLE(phys_dev);
if (!handle || acpi_bus_get_device(handle, &adev)) {
dev_dbg(phys_dev, "ACPI handle without context in %s!\n",
__func__);
return -ENODEV;
}
return __acpi_device_run_wake(adev, enable);
}
EXPORT_SYMBOL(acpi_pm_device_run_wake);
#else
static inline void acpi_wakeup_device(acpi_handle handle, u32 event,
void *context) {}
#endif /* CONFIG_PM_RUNTIME */
#ifdef CONFIG_PM_SLEEP
/**
* __acpi_device_sleep_wake - Enable or disable device to wake up the system.
* @dev: Device to enable/desible to wake up the system.
* @target_state: System state the device is supposed to wake up from.
* @enable: Whether to enable or disable @dev to wake up the system.
*/
int __acpi_device_sleep_wake(struct acpi_device *adev, u32 target_state,
bool enable)
{
return enable ?
acpi_enable_wakeup_device_power(adev, target_state) :
acpi_disable_wakeup_device_power(adev);
}
/**
* acpi_pm_device_sleep_wake - Enable or disable device to wake up the system.
* @dev: Device to enable/desible to wake up the system from sleep states.
* @enable: Whether to enable or disable @dev to wake up the system.
*/
int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
{
acpi_handle handle;
struct acpi_device *adev;
int error;
if (!device_can_wakeup(dev))
return -EINVAL;
handle = ACPI_HANDLE(dev);
if (!handle || acpi_bus_get_device(handle, &adev)) {
dev_dbg(dev, "ACPI handle without context in %s!\n", __func__);
return -ENODEV;
}
error = __acpi_device_sleep_wake(adev, acpi_target_system_state(),
enable);
if (!error)
dev_info(dev, "System wakeup %s by ACPI\n",
enable ? "enabled" : "disabled");
return error;
}
#endif /* CONFIG_PM_SLEEP */
/**
* 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_dev_pm_full_power - Put ACPI device into the full-power state.
* @adev: ACPI device node to put into the full-power state.
*/
static int acpi_dev_pm_full_power(struct acpi_device *adev)
{
return acpi_device_power_manageable(adev) ?
acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
}
#ifdef CONFIG_PM_RUNTIME
/**
* acpi_dev_runtime_suspend - Put device into a low-power state using ACPI.
* @dev: Device to put into a low-power state.
*
* Put the given device into a runtime low-power state using the standard ACPI
* mechanism. Set up remote wakeup if desired, choose the state to put the
* device into (this checks if remote wakeup is expected to work too), and set
* the power state of the device.
*/
int acpi_dev_runtime_suspend(struct device *dev)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
bool remote_wakeup;
int error;
if (!adev)
return 0;
remote_wakeup = dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) >
PM_QOS_FLAGS_NONE;
error = __acpi_device_run_wake(adev, remote_wakeup);
if (remote_wakeup && error)
return -EAGAIN;
error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
if (error)
__acpi_device_run_wake(adev, false);
return error;
}
EXPORT_SYMBOL_GPL(acpi_dev_runtime_suspend);
/**
* acpi_dev_runtime_resume - Put device into the full-power state using ACPI.
* @dev: Device to put into the full-power state.
*
* Put the given device into the full-power state using the standard ACPI
* mechanism at run time. Set the power state of the device to ACPI D0 and
* disable remote wakeup.
*/
int acpi_dev_runtime_resume(struct device *dev)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
int error;
if (!adev)
return 0;
error = acpi_dev_pm_full_power(adev);
__acpi_device_run_wake(adev, false);
return error;
}
EXPORT_SYMBOL_GPL(acpi_dev_runtime_resume);
/**
* acpi_subsys_runtime_suspend - Suspend device using ACPI.
* @dev: Device to suspend.
*
* Carry out the generic runtime suspend procedure for @dev and use ACPI to put
* it into a runtime low-power state.
*/
int acpi_subsys_runtime_suspend(struct device *dev)
{
int ret = pm_generic_runtime_suspend(dev);
return ret ? ret : acpi_dev_runtime_suspend(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
/**
* acpi_subsys_runtime_resume - Resume device using ACPI.
* @dev: Device to Resume.
*
* Use ACPI to put the given device into the full-power state and carry out the
* generic runtime resume procedure for it.
*/
int acpi_subsys_runtime_resume(struct device *dev)
{
int ret = acpi_dev_runtime_resume(dev);
return ret ? ret : pm_generic_runtime_resume(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
#endif /* CONFIG_PM_RUNTIME */
#ifdef CONFIG_PM_SLEEP
/**
* acpi_dev_suspend_late - Put device into a low-power state using ACPI.
* @dev: Device to put into a low-power state.
*
* Put the given device into a low-power state during system transition to a
* sleep state using the standard ACPI mechanism. Set up system wakeup if
* desired, choose the state to put the device into (this checks if system
* wakeup is expected to work too), and set the power state of the device.
*/
int acpi_dev_suspend_late(struct device *dev)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
u32 target_state;
bool wakeup;
int error;
if (!adev)
return 0;
target_state = acpi_target_system_state();
wakeup = device_may_wakeup(dev);
error = __acpi_device_sleep_wake(adev, target_state, wakeup);
if (wakeup && error)
return error;
error = acpi_dev_pm_low_power(dev, adev, target_state);
if (error)
__acpi_device_sleep_wake(adev, ACPI_STATE_UNKNOWN, false);
return error;
}
EXPORT_SYMBOL_GPL(acpi_dev_suspend_late);
/**
* acpi_dev_resume_early - Put device into the full-power state using ACPI.
* @dev: Device to put into the full-power state.
*
* Put the given device into the full-power state using the standard ACPI
* mechanism during system transition to the working state. Set the power
* state of the device to ACPI D0 and disable remote wakeup.
*/
int acpi_dev_resume_early(struct device *dev)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
int error;
if (!adev)
return 0;
error = acpi_dev_pm_full_power(adev);
__acpi_device_sleep_wake(adev, ACPI_STATE_UNKNOWN, false);
return error;
}
EXPORT_SYMBOL_GPL(acpi_dev_resume_early);
/**
* acpi_subsys_prepare - Prepare device for system transition to a sleep state.
* @dev: Device to prepare.
*/
int acpi_subsys_prepare(struct device *dev)
{
/*
* Follow PCI and resume devices suspended at run time before running
* their system suspend callbacks.
*/
pm_runtime_resume(dev);
return pm_generic_prepare(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
/**
* acpi_subsys_suspend_late - Suspend device using ACPI.
* @dev: Device to suspend.
*
* Carry out the generic late suspend procedure for @dev and use ACPI to put
* it into a low-power state during system transition into a sleep state.
*/
int acpi_subsys_suspend_late(struct device *dev)
{
int ret = pm_generic_suspend_late(dev);
return ret ? ret : acpi_dev_suspend_late(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
/**
* acpi_subsys_resume_early - Resume device using ACPI.
* @dev: Device to Resume.
*
* Use ACPI to put the given device into the full-power state and carry out the
* generic early resume procedure for it during system transition into the
* working state.
*/
int acpi_subsys_resume_early(struct device *dev)
{
int ret = acpi_dev_resume_early(dev);
return ret ? ret : pm_generic_resume_early(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_resume_early);
#endif /* CONFIG_PM_SLEEP */
static struct dev_pm_domain acpi_general_pm_domain = {
.ops = {
#ifdef CONFIG_PM_RUNTIME
.runtime_suspend = acpi_subsys_runtime_suspend,
.runtime_resume = acpi_subsys_runtime_resume,
#endif
#ifdef CONFIG_PM_SLEEP
.prepare = acpi_subsys_prepare,
.suspend_late = acpi_subsys_suspend_late,
.resume_early = acpi_subsys_resume_early,
.poweroff_late = acpi_subsys_suspend_late,
.restore_early = acpi_subsys_resume_early,
#endif
},
};
/**
* acpi_dev_pm_attach - Prepare device for ACPI power management.
* @dev: Device to prepare.
* @power_on: Whether or not to power on the device.
*
* If @dev has a valid ACPI handle that has a valid struct acpi_device object
* attached to it, install a wakeup notification handler for the device and
* add it to the general ACPI PM domain. If @power_on is set, the device will
* be put into the ACPI D0 state before the function returns.
*
* This assumes that the @dev's bus type uses generic power management callbacks
* (or doesn't use any power management callbacks at all).
*
* Callers must ensure proper synchronization of this function with power
* management callbacks.
*/
int acpi_dev_pm_attach(struct device *dev, bool power_on)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
if (!adev)
return -ENODEV;
if (dev->pm_domain)
return -EEXIST;
acpi_add_pm_notifier(adev, acpi_wakeup_device, dev);
dev->pm_domain = &acpi_general_pm_domain;
if (power_on) {
acpi_dev_pm_full_power(adev);
__acpi_device_run_wake(adev, false);
}
return 0;
}
EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
/**
* acpi_dev_pm_detach - Remove ACPI power management from the device.
* @dev: Device to take care of.
* @power_off: Whether or not to try to remove power from the device.
*
* Remove the device from the general ACPI PM domain and remove its wakeup
* notifier. If @power_off is set, additionally remove power from the device if
* possible.
*
* Callers must ensure proper synchronization of this function with power
* management callbacks.
*/
void acpi_dev_pm_detach(struct device *dev, bool power_off)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
if (adev && dev->pm_domain == &acpi_general_pm_domain) {
dev->pm_domain = NULL;
acpi_remove_pm_notifier(adev, acpi_wakeup_device);
if (power_off) {
/*
* If the device's PM QoS resume latency limit or flags
* have been exposed to user space, they have to be
* hidden at this point, so that they don't affect the
* choice of the low-power state to put the device into.
*/
dev_pm_qos_hide_latency_limit(dev);
dev_pm_qos_hide_flags(dev);
__acpi_device_run_wake(adev, false);
acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
}
}
}
EXPORT_SYMBOL_GPL(acpi_dev_pm_detach);
#endif /* CONFIG_PM */