diff options
Diffstat (limited to 'drivers/acpi/device_pm.c')
| -rw-r--r-- | drivers/acpi/device_pm.c | 1517 |
1 files changed, 1517 insertions, 0 deletions
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c new file mode 100644 index 000000000..f007116a8 --- /dev/null +++ b/drivers/acpi/device_pm.c @@ -0,0 +1,1517 @@ +// 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> + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + */ + +#define pr_fmt(fmt) "PM: " fmt + +#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 "fan.h" +#include "internal.h" + +/** + * 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; + struct acpi_device *parent; + int error; + + if (!device || !state) + return -EINVAL; + + parent = acpi_dev_parent(device); + + if (!device->flags.power_manageable) { + /* TBD: Non-recursive algorithm for walking up hierarchy. */ + *state = parent ? 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 && parent && + parent->power.state == ACPI_STATE_UNKNOWN && + result == ACPI_STATE_D0) + parent->power.state = ACPI_STATE_D0; + + *state = result; + + out: + acpi_handle_debug(device->handle, "Power state: %s\n", + 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) + goto no_change; + + 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 D3cold is not supported, 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) { + acpi_handle_debug(device->handle, "Power state %s not supported\n", + acpi_power_state_string(state)); + return -ENODEV; + } + + if (!device->power.flags.ignore_parent) { + struct acpi_device *parent; + + parent = acpi_dev_parent(device); + if (parent && state < parent->power.state) { + acpi_handle_debug(device->handle, + "Cannot transition to %s for parent in %s\n", + acpi_power_state_string(state), + acpi_power_state_string(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) { + acpi_handle_debug(device->handle, + "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) + goto no_change; + + /* + * 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) + goto no_change; + } + + result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0); + } + +end: + if (result) { + acpi_handle_debug(device->handle, + "Failed to change power state to %s\n", + acpi_power_state_string(target_state)); + } else { + device->power.state = target_state; + acpi_handle_debug(device->handle, "Power state changed to %s\n", + acpi_power_state_string(target_state)); + } + + return result; + +no_change: + acpi_handle_debug(device->handle, "Already in %s\n", + acpi_power_state_string(state)); + return 0; +} +EXPORT_SYMBOL(acpi_device_set_power); + +int acpi_bus_set_power(acpi_handle handle, int state) +{ + struct acpi_device *device = acpi_fetch_acpi_dev(handle); + + if (device) + return acpi_device_set_power(device, state); + + return -ENODEV; +} +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); + +static int fix_up_power_if_applicable(struct acpi_device *adev, void *not_used) +{ + if (adev->status.present && adev->status.enabled) + acpi_device_fix_up_power(adev); + + return 0; +} + +/** + * acpi_device_fix_up_power_extended - Force device and its children into D0. + * @adev: Parent device object whose power state is to be fixed up. + * + * Call acpi_device_fix_up_power() for @adev and its children so long as they + * are reported as present and enabled. + */ +void acpi_device_fix_up_power_extended(struct acpi_device *adev) +{ + acpi_device_fix_up_power(adev); + acpi_dev_for_each_child(adev, fix_up_power_if_applicable, NULL); +} +EXPORT_SYMBOL_GPL(acpi_device_fix_up_power_extended); + +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 = acpi_fetch_acpi_dev(handle); + + if (device) + return acpi_device_update_power(device, state_p); + + return -ENODEV; +} +EXPORT_SYMBOL_GPL(acpi_bus_update_power); + +bool acpi_bus_power_manageable(acpi_handle handle) +{ + struct acpi_device *device = acpi_fetch_acpi_dev(handle); + + return device && device->flags.power_manageable; +} +EXPORT_SYMBOL(acpi_bus_power_manageable); + +static int acpi_power_up_if_adr_present(struct acpi_device *adev, void *not_used) +{ + if (!(adev->flags.power_manageable && adev->pnp.type.bus_address)) + return 0; + + acpi_handle_debug(adev->handle, "Power state: %s\n", + acpi_power_state_string(adev->power.state)); + + if (adev->power.state == ACPI_STATE_D3_COLD) + return acpi_device_set_power(adev, ACPI_STATE_D0); + + return 0; +} + +/** + * acpi_dev_power_up_children_with_adr - Power up childres with valid _ADR + * @adev: Parent ACPI device object. + * + * Change the power states of the direct children of @adev that are in D3cold + * and hold valid _ADR objects to D0 in order to allow bus (e.g. PCI) + * enumeration code to access them. + */ +void acpi_dev_power_up_children_with_adr(struct acpi_device *adev) +{ + acpi_dev_for_each_child(adev, acpi_power_up_if_adr_present, NULL); +} + +/** + * acpi_dev_power_state_for_wake - Deepest power state for wakeup signaling + * @adev: ACPI companion of the target device. + * + * Evaluate _S0W for @adev and return the value produced by it or return + * ACPI_STATE_UNKNOWN on errors (including _S0W not present). + */ +u8 acpi_dev_power_state_for_wake(struct acpi_device *adev) +{ + unsigned long long state; + acpi_status status; + + status = acpi_evaluate_integer(adev->handle, "_S0W", NULL, &state); + if (ACPI_FAILURE(status)) + return ACPI_STATE_UNKNOWN; + + return state; +} + +#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_get_acpi_dev(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_put_acpi_dev(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 = acpi_fetch_acpi_dev(handle); + + return device && 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 if (device_may_wakeup(dev) && dev->power.wakeirq) { + /* + * The ACPI subsystem doesn't manage the wake bit for IRQs + * defined with ExclusiveAndWake and SharedAndWake. Instead we + * expect them to be managed via the PM subsystem. Drivers + * should call dev_pm_set_wake_irq to register an IRQ as a wake + * source. + * + * If a device has a wake IRQ attached we need to check the + * _S0W method to get the correct wake D-state. Otherwise we + * end up putting the device into D3Cold which will more than + * likely disable wake functionality. + */ + wakeup = true; + } else { + /* ACPI GPE is specified in _PRW. */ + 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) +{ + struct acpi_device_wakeup *wakeup = &adev->wakeup; + acpi_status status; + int error = 0; + + mutex_lock(&acpi_wakeup_lock); + + /* + * If the device wakeup power is already enabled, disable it and enable + * it again in case it depends on the configuration of subordinate + * devices and the conditions have changed since it was enabled last + * time. + */ + if (wakeup->enable_count > 0) + acpi_disable_wakeup_device_power(adev); + + error = acpi_enable_wakeup_device_power(adev, target_state); + if (error) { + if (wakeup->enable_count > 0) { + acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number); + wakeup->enable_count = 0; + } + goto out; + } + + if (wakeup->enable_count > 0) + goto inc; + + 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: + if (wakeup->enable_count < INT_MAX) + wakeup->enable_count++; + else + acpi_handle_info(adev->handle, "Wakeup enable count out of bounds!\n"); + +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); +} + +/** + * 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); +} + +/** + * 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) +{ + 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()); + if (!error) + dev_dbg(dev, "Wakeup enabled by ACPI\n"); + + return error; +} +EXPORT_SYMBOL_GPL(acpi_pm_set_device_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_skip_suspend(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_skip_suspend(dev)) + 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. + */ + if (device_can_wakeup(dev) && !device_may_wakeup(dev)) + dev->power.may_skip_resume = false; + + 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_skip_resume(dev)) + return 0; + + 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, but only do that if device either defines early resume + * handler, or does not define power operations at all. Otherwise powering up + * of the device is postponed to the normal resume phase. + */ +static int acpi_subsys_resume_early(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int ret; + + if (dev_pm_skip_resume(dev)) + return 0; + + if (pm && !pm->resume_early) { + dev_dbg(dev, "postponing D0 transition to normal resume stage\n"); + return 0; + } + + ret = acpi_dev_resume(dev); + return ret ? ret : pm_generic_resume_early(dev); +} + +/** + * acpi_subsys_resume - Resume device using ACPI. + * @dev: Device to Resume. + * + * Use ACPI to put the given device into the full-power state if it has not been + * powered up during early resume phase, and carry out the generic resume + * procedure for it during system transition into the working state. + */ +static int acpi_subsys_resume(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int ret = 0; + + if (!dev_pm_skip_resume(dev) && pm && !pm->resume_early) { + dev_dbg(dev, "executing postponed D0 transition\n"); + ret = acpi_dev_resume(dev); + } + + return ret ? ret : pm_generic_resume(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_skip_suspend(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_skip_suspend(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, + .resume = acpi_subsys_resume, + .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) +{ + /* + * Skip devices whose ACPI companions match the device IDs below, + * because they require special power management handling incompatible + * with the generic ACPI PM domain. + */ + static const struct acpi_device_id special_pm_ids[] = { + ACPI_FAN_DEVICE_IDS, + {} + }; + struct acpi_device *adev = ACPI_COMPANION(dev); + + if (!adev || !acpi_match_device_ids(adev, special_pm_ids)) + 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); + +/** + * acpi_storage_d3 - Check if D3 should be used in the suspend path + * @dev: Device to check + * + * Return %true if the platform firmware wants @dev to be programmed + * into D3hot or D3cold (if supported) in the suspend path, or %false + * when there is no specific preference. On some platforms, if this + * hint is ignored, @dev may remain unresponsive after suspending the + * platform as a whole. + * + * Although the property has storage in the name it actually is + * applied to the PCIe slot and plugging in a non-storage device the + * same platform restrictions will likely apply. + */ +bool acpi_storage_d3(struct device *dev) +{ + struct acpi_device *adev = ACPI_COMPANION(dev); + u8 val; + + if (force_storage_d3()) + return true; + + if (!adev) + return false; + if (fwnode_property_read_u8(acpi_fwnode_handle(adev), "StorageD3Enable", + &val)) + return false; + return val == 1; +} +EXPORT_SYMBOL_GPL(acpi_storage_d3); + +/** + * acpi_dev_state_d0 - Tell if the device is in D0 power state + * @dev: Physical device the ACPI power state of which to check + * + * On a system without ACPI, return true. On a system with ACPI, return true if + * the current ACPI power state of the device is D0, or false otherwise. + * + * Note that the power state of a device is not well-defined after it has been + * passed to acpi_device_set_power() and before that function returns, so it is + * not valid to ask for the ACPI power state of the device in that time frame. + * + * This function is intended to be used in a driver's probe or remove + * function. See Documentation/firmware-guide/acpi/non-d0-probe.rst for + * more information. + */ +bool acpi_dev_state_d0(struct device *dev) +{ + struct acpi_device *adev = ACPI_COMPANION(dev); + + if (!adev) + return true; + + return adev->power.state == ACPI_STATE_D0; +} +EXPORT_SYMBOL_GPL(acpi_dev_state_d0); + +#endif /* CONFIG_PM */ |