device_pm.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* drivers/acpi/device_pm.c - ACPI device power management routines.
*
* Copyright (C) 2012, Intel Corp.
* Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#include <linux/acpi.h>
#include <linux/export.h>
#include <linux/mutex.h>
#include <linux/pm_qos.h>
#include <linux/pm_domain.h>
#include <linux/pm_runtime.h>
#include <linux/suspend.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)";
}
}
static int acpi_dev_pm_explicit_get(struct acpi_device *device, int *state)
{
unsigned long long psc;
acpi_status status;
status = acpi_evaluate_integer(device->handle, "_PSC", NULL, &psc);
if (ACPI_FAILURE(status))
return -ENODEV;
*state = psc;
return 0;
}
/**
* 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).
*
* Also, it does not update power resource reference counters to ensure that
* the power state returned by it will be persistent and it may return a power
* state shallower than previously set by acpi_device_set_power() for @device
* (if that power state depends on any power resources).
*/
int acpi_device_get_power(struct acpi_device *device, int *state)
{
int result = ACPI_STATE_UNKNOWN;
int error;
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) {
error = acpi_power_get_inferred_state(device, &result);
if (error)
return error;
}
if (device->power.flags.explicit_get) {
int psc;
error = acpi_dev_pm_explicit_get(device, &psc);
if (error)
return error;
/*
* The power resources settings may indicate a power state
* shallower than the actual power state of the device, because
* the same power resources may be referenced by other devices.
*
* For systems predating ACPI 4.0 we assume that D3hot is the
* deepest state that can be supported.
*/
if (psc > result && psc < ACPI_STATE_D3_COLD)
result = psc;
else if (result == ACPI_STATE_UNKNOWN)
result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : 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 target_state = state;
int result = 0;
if (!device || !device->flags.power_manageable
|| (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
return -EINVAL;
acpi_handle_debug(device->handle, "Power state change: %s -> %s\n",
acpi_power_state_string(device->power.state),
acpi_power_state_string(state));
/* Make sure this is a valid target state */
/* There is a special case for D0 addressed below. */
if (state > ACPI_STATE_D0 && 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 (state == ACPI_STATE_D3_COLD) {
/*
* For transitions to D3cold we need to execute _PS3 and then
* possibly drop references to the power resources in use.
*/
state = ACPI_STATE_D3_HOT;
/* If _PR3 is not available, use D3hot as the target state. */
if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid)
target_state = state;
} else 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;
}
/*
* Transition Power
* ----------------
* In accordance with ACPI 6, _PSx is executed before manipulating power
* resources, unless the target state is D0, in which case _PS0 is
* supposed to be executed after turning the power resources on.
*/
if (state > ACPI_STATE_D0) {
/*
* According to ACPI 6, devices cannot go from lower-power
* (deeper) states to higher-power (shallower) states.
*/
if (state < device->power.state) {
dev_warn(&device->dev, "Cannot transition from %s to %s\n",
acpi_power_state_string(device->power.state),
acpi_power_state_string(state));
return -ENODEV;
}
/*
* If the device goes from D3hot to D3cold, _PS3 has been
* evaluated for it already, so skip it in that case.
*/
if (device->power.state < ACPI_STATE_D3_HOT) {
result = acpi_dev_pm_explicit_set(device, state);
if (result)
goto end;
}
if (device->power.flags.power_resources)
result = acpi_power_transition(device, target_state);
} else {
int cur_state = device->power.state;
if (device->power.flags.power_resources) {
result = acpi_power_transition(device, ACPI_STATE_D0);
if (result)
goto end;
}
if (cur_state == ACPI_STATE_D0) {
int psc;
/* Nothing to do here if _PSC is not present. */
if (!device->power.flags.explicit_get)
return 0;
/*
* The power state of the device was set to D0 last
* time, but that might have happened before a
* system-wide transition involving the platform
* firmware, so it may be necessary to evaluate _PS0
* for the device here. However, use extra care here
* and evaluate _PSC to check the device's current power
* state, and only invoke _PS0 if the evaluation of _PSC
* is successful and it returns a power state different
* from D0.
*/
result = acpi_dev_pm_explicit_get(device, &psc);
if (result || psc == ACPI_STATE_D0)
return 0;
}
result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
}
end:
if (result) {
dev_warn(&device->dev, "Failed to change power state to %s\n",
acpi_power_state_string(state));
} else {
device->power.state = target_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)) {
device->flags.initialized = false;
return -ENXIO;
}
result = acpi_device_get_power(device, &state);
if (result)
return result;
if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
/* Reference count the power resources. */
result = acpi_power_on_resources(device, state);
if (result)
return result;
if (state == ACPI_STATE_D0) {
/*
* If _PSC is not present and the state inferred from
* power resources appears to be D0, it still may be
* necessary to execute _PS0 at this point, because
* another device using the same power resources may
* have been put into D0 previously and that's why we
* see D0 here.
*/
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;
}
EXPORT_SYMBOL_GPL(acpi_device_fix_up_power);
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;
}
EXPORT_SYMBOL_GPL(acpi_device_update_power);
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);
static DEFINE_MUTEX(acpi_pm_notifier_install_lock);
void acpi_pm_wakeup_event(struct device *dev)
{
pm_wakeup_dev_event(dev, 0, acpi_s2idle_wakeup());
}
EXPORT_SYMBOL_GPL(acpi_pm_wakeup_event);
static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)
{
struct acpi_device *adev;
if (val != ACPI_NOTIFY_DEVICE_WAKE)
return;
acpi_handle_debug(handle, "Wake notify\n");
adev = acpi_bus_get_acpi_device(handle);
if (!adev)
return;
mutex_lock(&acpi_pm_notifier_lock);
if (adev->wakeup.flags.notifier_present) {
pm_wakeup_ws_event(adev->wakeup.ws, 0, acpi_s2idle_wakeup());
if (adev->wakeup.context.func) {
acpi_handle_debug(handle, "Running %pS for %s\n",
adev->wakeup.context.func,
dev_name(adev->wakeup.context.dev));
adev->wakeup.context.func(&adev->wakeup.context);
}
}
mutex_unlock(&acpi_pm_notifier_lock);
acpi_bus_put_acpi_device(adev);
}
/**
* acpi_add_pm_notifier - Register PM notify handler for given ACPI device.
* @adev: ACPI device to add the notify handler for.
* @dev: Device to generate a wakeup event for while handling the notification.
* @func: Work function to execute when handling the notification.
*
* 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, struct device *dev,
void (*func)(struct acpi_device_wakeup_context *context))
{
acpi_status status = AE_ALREADY_EXISTS;
if (!dev && !func)
return AE_BAD_PARAMETER;
mutex_lock(&acpi_pm_notifier_install_lock);
if (adev->wakeup.flags.notifier_present)
goto out;
status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,
acpi_pm_notify_handler, NULL);
if (ACPI_FAILURE(status))
goto out;
mutex_lock(&acpi_pm_notifier_lock);
adev->wakeup.ws = wakeup_source_register(&adev->dev,
dev_name(&adev->dev));
adev->wakeup.context.dev = dev;
adev->wakeup.context.func = func;
adev->wakeup.flags.notifier_present = true;
mutex_unlock(&acpi_pm_notifier_lock);
out:
mutex_unlock(&acpi_pm_notifier_install_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_status status = AE_BAD_PARAMETER;
mutex_lock(&acpi_pm_notifier_install_lock);
if (!adev->wakeup.flags.notifier_present)
goto out;
status = acpi_remove_notify_handler(adev->handle,
ACPI_SYSTEM_NOTIFY,
acpi_pm_notify_handler);
if (ACPI_FAILURE(status))
goto out;
mutex_lock(&acpi_pm_notifier_lock);
adev->wakeup.context.func = NULL;
adev->wakeup.context.dev = NULL;
wakeup_source_unregister(adev->wakeup.ws);
adev->wakeup.flags.notifier_present = false;
mutex_unlock(&acpi_pm_notifier_lock);
out:
mutex_unlock(&acpi_pm_notifier_install_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);
bool acpi_pm_device_can_wakeup(struct device *dev)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
return adev ? acpi_device_can_wakeup(adev) : false;
}
/**
* 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;
bool has_sxd = 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;
}
if (status == AE_OK)
has_sxd = true;
d_min = ret;
wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
&& adev->wakeup.sleep_state >= target_state;
} else {
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) {
/* No _SxW. In this case, the ACPI spec says that we
* must not go into any power state deeper than the
* value returned from _SxD.
*/
if (has_sxd && 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)
{
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_D2) {
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_D2;
}
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;
}
EXPORT_SYMBOL(acpi_pm_device_sleep_state);
/**
* acpi_pm_notify_work_func - ACPI devices wakeup notification work function.
* @context: Device wakeup context.
*/
static void acpi_pm_notify_work_func(struct acpi_device_wakeup_context *context)
{
struct device *dev = context->dev;
if (dev) {
pm_wakeup_event(dev, 0);
pm_request_resume(dev);
}
}
static DEFINE_MUTEX(acpi_wakeup_lock);
static int __acpi_device_wakeup_enable(struct acpi_device *adev,
u32 target_state, int max_count)
{
struct acpi_device_wakeup *wakeup = &adev->wakeup;
acpi_status status;
int error = 0;
mutex_lock(&acpi_wakeup_lock);
if (wakeup->enable_count >= max_count)
goto out;
if (wakeup->enable_count > 0)
goto inc;
error = acpi_enable_wakeup_device_power(adev, target_state);
if (error)
goto out;
status = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
if (ACPI_FAILURE(status)) {
acpi_disable_wakeup_device_power(adev);
error = -EIO;
goto out;
}
acpi_handle_debug(adev->handle, "GPE%2X enabled for wakeup\n",
(unsigned int)wakeup->gpe_number);
inc:
wakeup->enable_count++;
out:
mutex_unlock(&acpi_wakeup_lock);
return error;
}
/**
* acpi_device_wakeup_enable - Enable wakeup functionality for device.
* @adev: ACPI device to enable wakeup functionality for.
* @target_state: State the system is transitioning into.
*
* Enable the GPE associated with @adev so that it can generate wakeup signals
* for the device in response to external (remote) events and enable wakeup
* power for it.
*
* Callers must ensure that @adev is a valid ACPI device node before executing
* this function.
*/
static int acpi_device_wakeup_enable(struct acpi_device *adev, u32 target_state)
{
return __acpi_device_wakeup_enable(adev, target_state, 1);
}
/**
* acpi_device_wakeup_disable - Disable wakeup functionality for device.
* @adev: ACPI device to disable wakeup functionality for.
*
* Disable the GPE associated with @adev and disable wakeup power for it.
*
* Callers must ensure that @adev is a valid ACPI device node before executing
* this function.
*/
static void acpi_device_wakeup_disable(struct acpi_device *adev)
{
struct acpi_device_wakeup *wakeup = &adev->wakeup;
mutex_lock(&acpi_wakeup_lock);
if (!wakeup->enable_count)
goto out;
acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
acpi_disable_wakeup_device_power(adev);
wakeup->enable_count--;
out:
mutex_unlock(&acpi_wakeup_lock);
}
static int __acpi_pm_set_device_wakeup(struct device *dev, bool enable,
int max_count)
{
struct acpi_device *adev;
int error;
adev = ACPI_COMPANION(dev);
if (!adev) {
dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
return -ENODEV;
}
if (!acpi_device_can_wakeup(adev))
return -EINVAL;
if (!enable) {
acpi_device_wakeup_disable(adev);
dev_dbg(dev, "Wakeup disabled by ACPI\n");
return 0;
}
error = __acpi_device_wakeup_enable(adev, acpi_target_system_state(),
max_count);
if (!error)
dev_dbg(dev, "Wakeup enabled by ACPI\n");
return error;
}
/**
* acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device.
* @dev: Device to enable/disable to generate wakeup events.
* @enable: Whether to enable or disable the wakeup functionality.
*/
int acpi_pm_set_device_wakeup(struct device *dev, bool enable)
{
return __acpi_pm_set_device_wakeup(dev, enable, 1);
}
EXPORT_SYMBOL_GPL(acpi_pm_set_device_wakeup);
/**
* acpi_pm_set_bridge_wakeup - Enable/disable remote wakeup for given bridge.
* @dev: Bridge device to enable/disable to generate wakeup events.
* @enable: Whether to enable or disable the wakeup functionality.
*/
int acpi_pm_set_bridge_wakeup(struct device *dev, bool enable)
{
return __acpi_pm_set_device_wakeup(dev, enable, INT_MAX);
}
EXPORT_SYMBOL_GPL(acpi_pm_set_bridge_wakeup);
/**
* 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;
}
/**
* acpi_dev_suspend - Put device into a low-power state using ACPI.
* @dev: Device to put into a low-power state.
* @wakeup: Whether or not to enable wakeup for the device.
*
* Put the given device into a 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_suspend(struct device *dev, bool wakeup)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
u32 target_state = acpi_target_system_state();
int error;
if (!adev)
return 0;
if (wakeup && acpi_device_can_wakeup(adev)) {
error = acpi_device_wakeup_enable(adev, target_state);
if (error)
return -EAGAIN;
} else {
wakeup = false;
}
error = acpi_dev_pm_low_power(dev, adev, target_state);
if (error && wakeup)
acpi_device_wakeup_disable(adev);
return error;
}
EXPORT_SYMBOL_GPL(acpi_dev_suspend);
/**
* acpi_dev_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. Set the power state of the device to ACPI D0 and disable wakeup.
*/
int acpi_dev_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_wakeup_disable(adev);
return error;
}
EXPORT_SYMBOL_GPL(acpi_dev_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_suspend(dev, true);
}
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_resume(dev);
return ret ? ret : pm_generic_runtime_resume(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
#ifdef CONFIG_PM_SLEEP
static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev)
{
u32 sys_target = acpi_target_system_state();
int ret, state;
if (!pm_runtime_suspended(dev) || !adev || (adev->wakeup.flags.valid &&
device_may_wakeup(dev) != !!adev->wakeup.prepare_count))
return true;
if (sys_target == ACPI_STATE_S0)
return false;
if (adev->power.flags.dsw_present)
return true;
ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
if (ret)
return true;
return state != adev->power.state;
}
/**
* 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);
if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) {
int ret = dev->driver->pm->prepare(dev);
if (ret < 0)
return ret;
if (!ret && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
return 0;
}
return !acpi_dev_needs_resume(dev, adev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
/**
* acpi_subsys_complete - Finalize device's resume during system resume.
* @dev: Device to handle.
*/
void acpi_subsys_complete(struct device *dev)
{
pm_generic_complete(dev);
/*
* If the device had been runtime-suspended before the system went into
* the sleep state it is going out of and it has never been resumed till
* now, resume it in case the firmware powered it up.
*/
if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
pm_request_resume(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_complete);
/**
* acpi_subsys_suspend - Run the device driver's suspend callback.
* @dev: Device to handle.
*
* Follow PCI and resume devices from runtime suspend before running their
* system suspend callbacks, unless the driver can cope with runtime-suspended
* devices during system suspend and there are no ACPI-specific reasons for
* resuming them.
*/
int acpi_subsys_suspend(struct device *dev)
{
if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
pm_runtime_resume(dev);
return pm_generic_suspend(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_suspend);
/**
* 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;
if (dev_pm_smart_suspend_and_suspended(dev))
return 0;
ret = pm_generic_suspend_late(dev);
return ret ? ret : acpi_dev_suspend(dev, device_may_wakeup(dev));
}
EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
/**
* acpi_subsys_suspend_noirq - Run the device driver's "noirq" suspend callback.
* @dev: Device to suspend.
*/
int acpi_subsys_suspend_noirq(struct device *dev)
{
int ret;
if (dev_pm_smart_suspend_and_suspended(dev)) {
dev->power.may_skip_resume = true;
return 0;
}
ret = pm_generic_suspend_noirq(dev);
if (ret)
return ret;
/*
* If the target system sleep state is suspend-to-idle, it is sufficient
* to check whether or not the device's wakeup settings are good for
* runtime PM. Otherwise, the pm_resume_via_firmware() check will cause
* acpi_subsys_complete() to take care of fixing up the device's state
* anyway, if need be.
*/
dev->power.may_skip_resume = device_may_wakeup(dev) ||
!device_can_wakeup(dev);
return 0;
}
EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq);
/**
* acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback.
* @dev: Device to handle.
*/
static int acpi_subsys_resume_noirq(struct device *dev)
{
if (dev_pm_may_skip_resume(dev))
return 0;
/*
* Devices with DPM_FLAG_SMART_SUSPEND may be left in runtime suspend
* during system suspend, so update their runtime PM status to "active"
* as they will be put into D0 going forward.
*/
if (dev_pm_smart_suspend_and_suspended(dev))
pm_runtime_set_active(dev);
return pm_generic_resume_noirq(dev);
}
/**
* 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.
*/
static int acpi_subsys_resume_early(struct device *dev)
{
int ret = acpi_dev_resume(dev);
return ret ? ret : pm_generic_resume_early(dev);
}
/**
* acpi_subsys_freeze - Run the device driver's freeze callback.
* @dev: Device to handle.
*/
int acpi_subsys_freeze(struct device *dev)
{
/*
* Resume all runtime-suspended devices before creating a snapshot
* image of system memory, because the restore kernel generally cannot
* be expected to always handle them consistently and they need to be
* put into the runtime-active metastate during system resume anyway,
* so it is better to ensure that the state saved in the image will be
* always consistent with that.
*/
pm_runtime_resume(dev);
return pm_generic_freeze(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
/**
* acpi_subsys_restore_early - Restore device using ACPI.
* @dev: Device to restore.
*/
int acpi_subsys_restore_early(struct device *dev)
{
int ret = acpi_dev_resume(dev);
return ret ? ret : pm_generic_restore_early(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_restore_early);
/**
* acpi_subsys_poweroff - Run the device driver's poweroff callback.
* @dev: Device to handle.
*
* Follow PCI and resume devices from runtime suspend before running their
* system poweroff callbacks, unless the driver can cope with runtime-suspended
* devices during system suspend and there are no ACPI-specific reasons for
* resuming them.
*/
int acpi_subsys_poweroff(struct device *dev)
{
if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
pm_runtime_resume(dev);
return pm_generic_poweroff(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_poweroff);
/**
* acpi_subsys_poweroff_late - Run the device driver's poweroff callback.
* @dev: Device to handle.
*
* Carry out the generic late poweroff procedure for @dev and use ACPI to put
* it into a low-power state during system transition into a sleep state.
*/
static int acpi_subsys_poweroff_late(struct device *dev)
{
int ret;
if (dev_pm_smart_suspend_and_suspended(dev))
return 0;
ret = pm_generic_poweroff_late(dev);
if (ret)
return ret;
return acpi_dev_suspend(dev, device_may_wakeup(dev));
}
/**
* acpi_subsys_poweroff_noirq - Run the driver's "noirq" poweroff callback.
* @dev: Device to suspend.
*/
static int acpi_subsys_poweroff_noirq(struct device *dev)
{
if (dev_pm_smart_suspend_and_suspended(dev))
return 0;
return pm_generic_poweroff_noirq(dev);
}
#endif /* CONFIG_PM_SLEEP */
static struct dev_pm_domain acpi_general_pm_domain = {
.ops = {
.runtime_suspend = acpi_subsys_runtime_suspend,
.runtime_resume = acpi_subsys_runtime_resume,
#ifdef CONFIG_PM_SLEEP
.prepare = acpi_subsys_prepare,
.complete = acpi_subsys_complete,
.suspend = acpi_subsys_suspend,
.suspend_late = acpi_subsys_suspend_late,
.suspend_noirq = acpi_subsys_suspend_noirq,
.resume_noirq = acpi_subsys_resume_noirq,
.resume_early = acpi_subsys_resume_early,
.freeze = acpi_subsys_freeze,
.poweroff = acpi_subsys_poweroff,
.poweroff_late = acpi_subsys_poweroff_late,
.poweroff_noirq = acpi_subsys_poweroff_noirq,
.restore_early = acpi_subsys_restore_early,
#endif
},
};
/**
* 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.
*/
static 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_set(dev, NULL);
acpi_remove_pm_notifier(adev);
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_wakeup_disable(adev);
acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
}
}
}
/**
* 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 0;
/*
* Only attach the power domain to the first device if the
* companion is shared by multiple. This is to prevent doing power
* management twice.
*/
if (!acpi_device_is_first_physical_node(adev, dev))
return 0;
acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
dev_pm_domain_set(dev, &acpi_general_pm_domain);
if (power_on) {
acpi_dev_pm_full_power(adev);
acpi_device_wakeup_disable(adev);
}
dev->pm_domain->detach = acpi_dev_pm_detach;
return 1;
}
EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
#endif /* CONFIG_PM */