/* * 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. * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ #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 "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, 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; /* 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 (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; } 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 { if (device->power.flags.power_resources) { result = acpi_power_transition(device, ACPI_STATE_D0); if (result) goto end; } 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)) 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 void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used) { struct acpi_device *adev; if (val != ACPI_NOTIFY_DEVICE_WAKE) return; adev = acpi_bus_get_acpi_device(handle); if (!adev) return; mutex_lock(&acpi_pm_notifier_lock); if (adev->wakeup.flags.notifier_present) { __pm_wakeup_event(adev->wakeup.ws, 0); if (adev->wakeup.context.work.func) queue_pm_work(&adev->wakeup.context.work); } 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. * @work_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 (*work_func)(struct work_struct *work)) { acpi_status status = AE_ALREADY_EXISTS; if (!dev && !work_func) return AE_BAD_PARAMETER; mutex_lock(&acpi_pm_notifier_lock); if (adev->wakeup.flags.notifier_present) goto out; adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev)); adev->wakeup.context.dev = dev; if (work_func) INIT_WORK(&adev->wakeup.context.work, work_func); status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY, acpi_pm_notify_handler, NULL); 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_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, acpi_pm_notify_handler); if (ACPI_FAILURE(status)) goto out; if (adev->wakeup.context.work.func) { cancel_work_sync(&adev->wakeup.context.work); adev->wakeup.context.work.func = NULL; } adev->wakeup.context.dev = NULL; wakeup_source_unregister(adev->wakeup.ws); 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) { 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. * @work: Work item to handle. */ static void acpi_pm_notify_work_func(struct work_struct *work) { struct device *dev; dev = container_of(work, struct acpi_device_wakeup_context, work)->dev; if (dev) { pm_wakeup_event(dev, 0); pm_runtime_resume(dev); } } /** * acpi_device_wakeup - Enable/disable wakeup functionality for device. * @adev: ACPI device to enable/disable wakeup functionality for. * @target_state: State the system is transitioning into. * @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. */ static int acpi_device_wakeup(struct acpi_device *adev, u32 target_state, bool enable) { struct acpi_device_wakeup *wakeup = &adev->wakeup; if (enable) { acpi_status res; int error; error = acpi_enable_wakeup_device_power(adev, target_state); if (error) return error; if (adev->wakeup.flags.enabled) return 0; res = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number); if (ACPI_SUCCESS(res)) { adev->wakeup.flags.enabled = 1; } else { acpi_disable_wakeup_device_power(adev); return -EIO; } } else { if (adev->wakeup.flags.enabled) { acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number); adev->wakeup.flags.enabled = 0; } 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; if (!device_run_wake(phys_dev)) return -EINVAL; adev = ACPI_COMPANION(phys_dev); if (!adev) { dev_dbg(phys_dev, "ACPI companion missing in %s!\n", __func__); return -ENODEV; } return acpi_device_wakeup(adev, ACPI_STATE_S0, enable); } EXPORT_SYMBOL(acpi_pm_device_run_wake); #ifdef CONFIG_PM_SLEEP /** * 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) { struct acpi_device *adev; int error; if (!device_can_wakeup(dev)) return -EINVAL; adev = ACPI_COMPANION(dev); if (!adev) { dev_dbg(dev, "ACPI companion missing in %s!\n", __func__); return -ENODEV; } error = acpi_device_wakeup(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; } /** * 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_wakeup(adev, ACPI_STATE_S0, remote_wakeup); if (remote_wakeup && error) return -EAGAIN; error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0); if (error) acpi_device_wakeup(adev, ACPI_STATE_S0, 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_wakeup(adev, ACPI_STATE_S0, 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); #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) && acpi_device_can_wakeup(adev); error = acpi_device_wakeup(adev, target_state, wakeup); if (wakeup && error) return error; error = acpi_dev_pm_low_power(dev, adev, target_state); if (error) acpi_device_wakeup(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_wakeup(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) { 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; } EXPORT_SYMBOL_GPL(acpi_subsys_prepare); /** * acpi_subsys_suspend - Run the device driver's suspend callback. * @dev: Device to handle. * * Follow PCI and resume devices suspended at run time before running their * system suspend callbacks. */ int acpi_subsys_suspend(struct device *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 = 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); /** * acpi_subsys_freeze - Run the device driver's freeze callback. * @dev: Device to handle. */ int acpi_subsys_freeze(struct device *dev) { /* * This used to be done in acpi_subsys_prepare() for all devices and * some drivers may depend on it, so do it here. Ideally, however, * runtime-suspended devices should not be touched during freeze/thaw * transitions. */ pm_runtime_resume(dev); return pm_generic_freeze(dev); } EXPORT_SYMBOL_GPL(acpi_subsys_freeze); #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 = pm_complete_with_resume_check, .suspend = acpi_subsys_suspend, .suspend_late = acpi_subsys_suspend_late, .resume_early = acpi_subsys_resume_early, .freeze = acpi_subsys_freeze, .poweroff = acpi_subsys_suspend, .poweroff_late = acpi_subsys_suspend_late, .restore_early = acpi_subsys_resume_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(adev, ACPI_STATE_S0, false); 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 -ENODEV; if (dev->pm_domain) return -EEXIST; /* * 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 -EBUSY; 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(adev, ACPI_STATE_S0, false); } dev->pm_domain->detach = acpi_dev_pm_detach; return 0; } EXPORT_SYMBOL_GPL(acpi_dev_pm_attach); #endif /* CONFIG_PM */