/* * drivers/acpi/device_pm.c - ACPI device power management routines. * * Copyright (C) 2012, Intel Corp. * Author: Rafael J. Wysocki * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * 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 #include #include #include #include #include #include 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; } /** * acpi_device_power_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_max_in: Deepest low-power state to take into consideration. * @d_min_p: Location to store the upper limit of the allowed states range. * Return value: Preferred power state of the device on success, -ENODEV * (if there's no 'struct acpi_device' for @dev) or -EINVAL on failure * * Find the lowest power (highest number) ACPI device power state that the * device can be in while the system is in the state represented by * @target_state. If @d_min_p is set, the highest power (lowest number) device * power state that @dev can be in for the given system sleep state is stored * at the location pointed to by it. * * Callers must ensure that @dev and @adev are valid pointers and that @adev * actually corresponds to @dev before using this function. */ int acpi_device_power_state(struct device *dev, struct acpi_device *adev, u32 target_state, int d_max_in, int *d_min_p) { char acpi_method[] = "_SxD"; unsigned long long d_min, d_max; bool wakeup = false; if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3) 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; } acpi_method[2] = '0' + target_state; /* * If the sleep state is S0, the lowest limit from ACPI is D3, * but if the device has _S0W, we will use the value from _S0W * as the lowest limit from ACPI. Finally, we will constrain * the lowest limit with the specified one. */ d_min = ACPI_STATE_D0; d_max = ACPI_STATE_D3; /* * 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). * * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer * provided -- that's our fault recovery, we ignore retval. */ if (target_state > ACPI_STATE_S0) { acpi_evaluate_integer(adev->handle, acpi_method, NULL, &d_min); 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) { acpi_status status; acpi_method[3] = 'W'; status = acpi_evaluate_integer(adev->handle, acpi_method, NULL, &d_max); if (ACPI_FAILURE(status)) { if (target_state != ACPI_STATE_S0 || status != AE_NOT_FOUND) d_max = d_min; } else if (d_max < d_min) { /* Warn the user of the broken DSDT */ printk(KERN_WARNING "ACPI: Wrong value from %s\n", acpi_method); /* Sanitize it */ d_min = d_max; } } if (d_max_in < d_min) return -EINVAL; if (d_min_p) *d_min_p = d_min; /* constrain d_max with specified lowest limit (max number) */ 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; } } return d_max; } EXPORT_SYMBOL_GPL(acpi_device_power_state); /** * acpi_pm_device_sleep_state - Get preferred power state of ACPI device. * @dev: Device whose preferred target power state to return. * @d_min_p: Location to store the upper limit of the allowed states range. * @d_max_in: Deepest low-power state to take into consideration. * Return value: Preferred power state of the device on success, -ENODEV * (if there's no 'struct acpi_device' for @dev) or -EINVAL on 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 = DEVICE_ACPI_HANDLE(dev); struct acpi_device *adev; if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) { dev_dbg(dev, "ACPI handle without context in %s!\n", __func__); return -ENODEV; } return acpi_device_power_state(dev, adev, acpi_target_system_state(), d_max_in, d_min_p); } 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 = DEVICE_ACPI_HANDLE(phys_dev); if (!handle || ACPI_FAILURE(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 = DEVICE_ACPI_HANDLE(dev); if (!handle || ACPI_FAILURE(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_get_node - Get ACPI device node for the given physical device. * @dev: Device to get the ACPI node for. */ static struct acpi_device *acpi_dev_pm_get_node(struct device *dev) { acpi_handle handle = DEVICE_ACPI_HANDLE(dev); struct acpi_device *adev; return handle && !acpi_bus_get_device(handle, &adev) ? adev : NULL; } /** * 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 power_state; if (!acpi_device_power_manageable(adev)) return 0; power_state = acpi_device_power_state(dev, adev, system_state, ACPI_STATE_D3, NULL); if (power_state < ACPI_STATE_D0 || power_state > ACPI_STATE_D3) return -EIO; return acpi_device_set_power(adev, power_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_dev_pm_get_node(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_dev_pm_get_node(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_dev_pm_get_node(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_dev_pm_get_node(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, .runtime_idle = pm_generic_runtime_idle, #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_dev_pm_get_node(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_dev_pm_get_node(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);