| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * drivers/base/power/main.c - Where the driver meets power management. |
| * |
| * Copyright (c) 2003 Patrick Mochel |
| * Copyright (c) 2003 Open Source Development Lab |
| * |
| * The driver model core calls device_pm_add() when a device is registered. |
| * This will initialize the embedded device_pm_info object in the device |
| * and add it to the list of power-controlled devices. sysfs entries for |
| * controlling device power management will also be added. |
| * |
| * A separate list is used for keeping track of power info, because the power |
| * domain dependencies may differ from the ancestral dependencies that the |
| * subsystem list maintains. |
| */ |
| |
| #define pr_fmt(fmt) "PM: " fmt |
| |
| #include <linux/device.h> |
| #include <linux/export.h> |
| #include <linux/mutex.h> |
| #include <linux/pm.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/pm-trace.h> |
| #include <linux/pm_wakeirq.h> |
| #include <linux/interrupt.h> |
| #include <linux/sched.h> |
| #include <linux/sched/debug.h> |
| #include <linux/async.h> |
| #include <linux/suspend.h> |
| #include <trace/events/power.h> |
| #include <linux/cpufreq.h> |
| #include <linux/cpuidle.h> |
| #include <linux/devfreq.h> |
| #include <linux/timer.h> |
| |
| #include "../base.h" |
| #include "power.h" |
| |
| typedef int (*pm_callback_t)(struct device *); |
| |
| #define list_for_each_entry_rcu_locked(pos, head, member) \ |
| list_for_each_entry_rcu(pos, head, member, \ |
| device_links_read_lock_held()) |
| |
| /* |
| * The entries in the dpm_list list are in a depth first order, simply |
| * because children are guaranteed to be discovered after parents, and |
| * are inserted at the back of the list on discovery. |
| * |
| * Since device_pm_add() may be called with a device lock held, |
| * we must never try to acquire a device lock while holding |
| * dpm_list_mutex. |
| */ |
| |
| LIST_HEAD(dpm_list); |
| static LIST_HEAD(dpm_prepared_list); |
| static LIST_HEAD(dpm_suspended_list); |
| static LIST_HEAD(dpm_late_early_list); |
| static LIST_HEAD(dpm_noirq_list); |
| |
| struct suspend_stats suspend_stats; |
| static DEFINE_MUTEX(dpm_list_mtx); |
| static pm_message_t pm_transition; |
| |
| static int async_error; |
| |
| static const char *pm_verb(int event) |
| { |
| switch (event) { |
| case PM_EVENT_SUSPEND: |
| return "suspend"; |
| case PM_EVENT_RESUME: |
| return "resume"; |
| case PM_EVENT_FREEZE: |
| return "freeze"; |
| case PM_EVENT_QUIESCE: |
| return "quiesce"; |
| case PM_EVENT_HIBERNATE: |
| return "hibernate"; |
| case PM_EVENT_THAW: |
| return "thaw"; |
| case PM_EVENT_RESTORE: |
| return "restore"; |
| case PM_EVENT_RECOVER: |
| return "recover"; |
| default: |
| return "(unknown PM event)"; |
| } |
| } |
| |
| /** |
| * device_pm_sleep_init - Initialize system suspend-related device fields. |
| * @dev: Device object being initialized. |
| */ |
| void device_pm_sleep_init(struct device *dev) |
| { |
| dev->power.is_prepared = false; |
| dev->power.is_suspended = false; |
| dev->power.is_noirq_suspended = false; |
| dev->power.is_late_suspended = false; |
| init_completion(&dev->power.completion); |
| complete_all(&dev->power.completion); |
| dev->power.wakeup = NULL; |
| INIT_LIST_HEAD(&dev->power.entry); |
| } |
| |
| /** |
| * device_pm_lock - Lock the list of active devices used by the PM core. |
| */ |
| void device_pm_lock(void) |
| { |
| mutex_lock(&dpm_list_mtx); |
| } |
| |
| /** |
| * device_pm_unlock - Unlock the list of active devices used by the PM core. |
| */ |
| void device_pm_unlock(void) |
| { |
| mutex_unlock(&dpm_list_mtx); |
| } |
| |
| /** |
| * device_pm_add - Add a device to the PM core's list of active devices. |
| * @dev: Device to add to the list. |
| */ |
| void device_pm_add(struct device *dev) |
| { |
| /* Skip PM setup/initialization. */ |
| if (device_pm_not_required(dev)) |
| return; |
| |
| pr_debug("Adding info for %s:%s\n", |
| dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); |
| device_pm_check_callbacks(dev); |
| mutex_lock(&dpm_list_mtx); |
| if (dev->parent && dev->parent->power.is_prepared) |
| dev_warn(dev, "parent %s should not be sleeping\n", |
| dev_name(dev->parent)); |
| list_add_tail(&dev->power.entry, &dpm_list); |
| dev->power.in_dpm_list = true; |
| mutex_unlock(&dpm_list_mtx); |
| } |
| |
| /** |
| * device_pm_remove - Remove a device from the PM core's list of active devices. |
| * @dev: Device to be removed from the list. |
| */ |
| void device_pm_remove(struct device *dev) |
| { |
| if (device_pm_not_required(dev)) |
| return; |
| |
| pr_debug("Removing info for %s:%s\n", |
| dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); |
| complete_all(&dev->power.completion); |
| mutex_lock(&dpm_list_mtx); |
| list_del_init(&dev->power.entry); |
| dev->power.in_dpm_list = false; |
| mutex_unlock(&dpm_list_mtx); |
| device_wakeup_disable(dev); |
| pm_runtime_remove(dev); |
| device_pm_check_callbacks(dev); |
| } |
| |
| /** |
| * device_pm_move_before - Move device in the PM core's list of active devices. |
| * @deva: Device to move in dpm_list. |
| * @devb: Device @deva should come before. |
| */ |
| void device_pm_move_before(struct device *deva, struct device *devb) |
| { |
| pr_debug("Moving %s:%s before %s:%s\n", |
| deva->bus ? deva->bus->name : "No Bus", dev_name(deva), |
| devb->bus ? devb->bus->name : "No Bus", dev_name(devb)); |
| /* Delete deva from dpm_list and reinsert before devb. */ |
| list_move_tail(&deva->power.entry, &devb->power.entry); |
| } |
| |
| /** |
| * device_pm_move_after - Move device in the PM core's list of active devices. |
| * @deva: Device to move in dpm_list. |
| * @devb: Device @deva should come after. |
| */ |
| void device_pm_move_after(struct device *deva, struct device *devb) |
| { |
| pr_debug("Moving %s:%s after %s:%s\n", |
| deva->bus ? deva->bus->name : "No Bus", dev_name(deva), |
| devb->bus ? devb->bus->name : "No Bus", dev_name(devb)); |
| /* Delete deva from dpm_list and reinsert after devb. */ |
| list_move(&deva->power.entry, &devb->power.entry); |
| } |
| |
| /** |
| * device_pm_move_last - Move device to end of the PM core's list of devices. |
| * @dev: Device to move in dpm_list. |
| */ |
| void device_pm_move_last(struct device *dev) |
| { |
| pr_debug("Moving %s:%s to end of list\n", |
| dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); |
| list_move_tail(&dev->power.entry, &dpm_list); |
| } |
| |
| static ktime_t initcall_debug_start(struct device *dev, void *cb) |
| { |
| if (!pm_print_times_enabled) |
| return 0; |
| |
| dev_info(dev, "calling %pS @ %i, parent: %s\n", cb, |
| task_pid_nr(current), |
| dev->parent ? dev_name(dev->parent) : "none"); |
| return ktime_get(); |
| } |
| |
| static void initcall_debug_report(struct device *dev, ktime_t calltime, |
| void *cb, int error) |
| { |
| ktime_t rettime; |
| s64 nsecs; |
| |
| if (!pm_print_times_enabled) |
| return; |
| |
| rettime = ktime_get(); |
| nsecs = (s64) ktime_to_ns(ktime_sub(rettime, calltime)); |
| |
| dev_info(dev, "%pS returned %d after %Ld usecs\n", cb, error, |
| (unsigned long long)nsecs >> 10); |
| } |
| |
| /** |
| * dpm_wait - Wait for a PM operation to complete. |
| * @dev: Device to wait for. |
| * @async: If unset, wait only if the device's power.async_suspend flag is set. |
| */ |
| static void dpm_wait(struct device *dev, bool async) |
| { |
| if (!dev) |
| return; |
| |
| if (async || (pm_async_enabled && dev->power.async_suspend)) |
| wait_for_completion(&dev->power.completion); |
| } |
| |
| static int dpm_wait_fn(struct device *dev, void *async_ptr) |
| { |
| dpm_wait(dev, *((bool *)async_ptr)); |
| return 0; |
| } |
| |
| static void dpm_wait_for_children(struct device *dev, bool async) |
| { |
| device_for_each_child(dev, &async, dpm_wait_fn); |
| } |
| |
| static void dpm_wait_for_suppliers(struct device *dev, bool async) |
| { |
| struct device_link *link; |
| int idx; |
| |
| idx = device_links_read_lock(); |
| |
| /* |
| * If the supplier goes away right after we've checked the link to it, |
| * we'll wait for its completion to change the state, but that's fine, |
| * because the only things that will block as a result are the SRCU |
| * callbacks freeing the link objects for the links in the list we're |
| * walking. |
| */ |
| list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) |
| if (READ_ONCE(link->status) != DL_STATE_DORMANT) |
| dpm_wait(link->supplier, async); |
| |
| device_links_read_unlock(idx); |
| } |
| |
| static bool dpm_wait_for_superior(struct device *dev, bool async) |
| { |
| struct device *parent; |
| |
| /* |
| * If the device is resumed asynchronously and the parent's callback |
| * deletes both the device and the parent itself, the parent object may |
| * be freed while this function is running, so avoid that by reference |
| * counting the parent once more unless the device has been deleted |
| * already (in which case return right away). |
| */ |
| mutex_lock(&dpm_list_mtx); |
| |
| if (!device_pm_initialized(dev)) { |
| mutex_unlock(&dpm_list_mtx); |
| return false; |
| } |
| |
| parent = get_device(dev->parent); |
| |
| mutex_unlock(&dpm_list_mtx); |
| |
| dpm_wait(parent, async); |
| put_device(parent); |
| |
| dpm_wait_for_suppliers(dev, async); |
| |
| /* |
| * If the parent's callback has deleted the device, attempting to resume |
| * it would be invalid, so avoid doing that then. |
| */ |
| return device_pm_initialized(dev); |
| } |
| |
| static void dpm_wait_for_consumers(struct device *dev, bool async) |
| { |
| struct device_link *link; |
| int idx; |
| |
| idx = device_links_read_lock(); |
| |
| /* |
| * The status of a device link can only be changed from "dormant" by a |
| * probe, but that cannot happen during system suspend/resume. In |
| * theory it can change to "dormant" at that time, but then it is |
| * reasonable to wait for the target device anyway (eg. if it goes |
| * away, it's better to wait for it to go away completely and then |
| * continue instead of trying to continue in parallel with its |
| * unregistration). |
| */ |
| list_for_each_entry_rcu_locked(link, &dev->links.consumers, s_node) |
| if (READ_ONCE(link->status) != DL_STATE_DORMANT) |
| dpm_wait(link->consumer, async); |
| |
| device_links_read_unlock(idx); |
| } |
| |
| static void dpm_wait_for_subordinate(struct device *dev, bool async) |
| { |
| dpm_wait_for_children(dev, async); |
| dpm_wait_for_consumers(dev, async); |
| } |
| |
| /** |
| * pm_op - Return the PM operation appropriate for given PM event. |
| * @ops: PM operations to choose from. |
| * @state: PM transition of the system being carried out. |
| */ |
| static pm_callback_t pm_op(const struct dev_pm_ops *ops, pm_message_t state) |
| { |
| switch (state.event) { |
| #ifdef CONFIG_SUSPEND |
| case PM_EVENT_SUSPEND: |
| return ops->suspend; |
| case PM_EVENT_RESUME: |
| return ops->resume; |
| #endif /* CONFIG_SUSPEND */ |
| #ifdef CONFIG_HIBERNATE_CALLBACKS |
| case PM_EVENT_FREEZE: |
| case PM_EVENT_QUIESCE: |
| return ops->freeze; |
| case PM_EVENT_HIBERNATE: |
| return ops->poweroff; |
| case PM_EVENT_THAW: |
| case PM_EVENT_RECOVER: |
| return ops->thaw; |
| break; |
| case PM_EVENT_RESTORE: |
| return ops->restore; |
| #endif /* CONFIG_HIBERNATE_CALLBACKS */ |
| } |
| |
| return NULL; |
| } |
| |
| /** |
| * pm_late_early_op - Return the PM operation appropriate for given PM event. |
| * @ops: PM operations to choose from. |
| * @state: PM transition of the system being carried out. |
| * |
| * Runtime PM is disabled for @dev while this function is being executed. |
| */ |
| static pm_callback_t pm_late_early_op(const struct dev_pm_ops *ops, |
| pm_message_t state) |
| { |
| switch (state.event) { |
| #ifdef CONFIG_SUSPEND |
| case PM_EVENT_SUSPEND: |
| return ops->suspend_late; |
| case PM_EVENT_RESUME: |
| return ops->resume_early; |
| #endif /* CONFIG_SUSPEND */ |
| #ifdef CONFIG_HIBERNATE_CALLBACKS |
| case PM_EVENT_FREEZE: |
| case PM_EVENT_QUIESCE: |
| return ops->freeze_late; |
| case PM_EVENT_HIBERNATE: |
| return ops->poweroff_late; |
| case PM_EVENT_THAW: |
| case PM_EVENT_RECOVER: |
| return ops->thaw_early; |
| case PM_EVENT_RESTORE: |
| return ops->restore_early; |
| #endif /* CONFIG_HIBERNATE_CALLBACKS */ |
| } |
| |
| return NULL; |
| } |
| |
| /** |
| * pm_noirq_op - Return the PM operation appropriate for given PM event. |
| * @ops: PM operations to choose from. |
| * @state: PM transition of the system being carried out. |
| * |
| * The driver of @dev will not receive interrupts while this function is being |
| * executed. |
| */ |
| static pm_callback_t pm_noirq_op(const struct dev_pm_ops *ops, pm_message_t state) |
| { |
| switch (state.event) { |
| #ifdef CONFIG_SUSPEND |
| case PM_EVENT_SUSPEND: |
| return ops->suspend_noirq; |
| case PM_EVENT_RESUME: |
| return ops->resume_noirq; |
| #endif /* CONFIG_SUSPEND */ |
| #ifdef CONFIG_HIBERNATE_CALLBACKS |
| case PM_EVENT_FREEZE: |
| case PM_EVENT_QUIESCE: |
| return ops->freeze_noirq; |
| case PM_EVENT_HIBERNATE: |
| return ops->poweroff_noirq; |
| case PM_EVENT_THAW: |
| case PM_EVENT_RECOVER: |
| return ops->thaw_noirq; |
| case PM_EVENT_RESTORE: |
| return ops->restore_noirq; |
| #endif /* CONFIG_HIBERNATE_CALLBACKS */ |
| } |
| |
| return NULL; |
| } |
| |
| static void pm_dev_dbg(struct device *dev, pm_message_t state, const char *info) |
| { |
| dev_dbg(dev, "%s%s%s\n", info, pm_verb(state.event), |
| ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ? |
| ", may wakeup" : ""); |
| } |
| |
| static void pm_dev_err(struct device *dev, pm_message_t state, const char *info, |
| int error) |
| { |
| pr_err("Device %s failed to %s%s: error %d\n", |
| dev_name(dev), pm_verb(state.event), info, error); |
| } |
| |
| static void dpm_show_time(ktime_t starttime, pm_message_t state, int error, |
| const char *info) |
| { |
| ktime_t calltime; |
| u64 usecs64; |
| int usecs; |
| |
| calltime = ktime_get(); |
| usecs64 = ktime_to_ns(ktime_sub(calltime, starttime)); |
| do_div(usecs64, NSEC_PER_USEC); |
| usecs = usecs64; |
| if (usecs == 0) |
| usecs = 1; |
| |
| pm_pr_dbg("%s%s%s of devices %s after %ld.%03ld msecs\n", |
| info ?: "", info ? " " : "", pm_verb(state.event), |
| error ? "aborted" : "complete", |
| usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC); |
| } |
| |
| static int dpm_run_callback(pm_callback_t cb, struct device *dev, |
| pm_message_t state, const char *info) |
| { |
| ktime_t calltime; |
| int error; |
| |
| if (!cb) |
| return 0; |
| |
| calltime = initcall_debug_start(dev, cb); |
| |
| pm_dev_dbg(dev, state, info); |
| trace_device_pm_callback_start(dev, info, state.event); |
| error = cb(dev); |
| trace_device_pm_callback_end(dev, error); |
| suspend_report_result(cb, error); |
| |
| initcall_debug_report(dev, calltime, cb, error); |
| |
| return error; |
| } |
| |
| #ifdef CONFIG_DPM_WATCHDOG |
| struct dpm_watchdog { |
| struct device *dev; |
| struct task_struct *tsk; |
| struct timer_list timer; |
| }; |
| |
| #define DECLARE_DPM_WATCHDOG_ON_STACK(wd) \ |
| struct dpm_watchdog wd |
| |
| /** |
| * dpm_watchdog_handler - Driver suspend / resume watchdog handler. |
| * @t: The timer that PM watchdog depends on. |
| * |
| * Called when a driver has timed out suspending or resuming. |
| * There's not much we can do here to recover so panic() to |
| * capture a crash-dump in pstore. |
| */ |
| static void dpm_watchdog_handler(struct timer_list *t) |
| { |
| struct dpm_watchdog *wd = from_timer(wd, t, timer); |
| |
| dev_emerg(wd->dev, "**** DPM device timeout ****\n"); |
| show_stack(wd->tsk, NULL, KERN_EMERG); |
| panic("%s %s: unrecoverable failure\n", |
| dev_driver_string(wd->dev), dev_name(wd->dev)); |
| } |
| |
| /** |
| * dpm_watchdog_set - Enable pm watchdog for given device. |
| * @wd: Watchdog. Must be allocated on the stack. |
| * @dev: Device to handle. |
| */ |
| static void dpm_watchdog_set(struct dpm_watchdog *wd, struct device *dev) |
| { |
| struct timer_list *timer = &wd->timer; |
| |
| wd->dev = dev; |
| wd->tsk = current; |
| |
| timer_setup_on_stack(timer, dpm_watchdog_handler, 0); |
| /* use same timeout value for both suspend and resume */ |
| timer->expires = jiffies + HZ * CONFIG_DPM_WATCHDOG_TIMEOUT; |
| add_timer(timer); |
| } |
| |
| /** |
| * dpm_watchdog_clear - Disable suspend/resume watchdog. |
| * @wd: Watchdog to disable. |
| */ |
| static void dpm_watchdog_clear(struct dpm_watchdog *wd) |
| { |
| struct timer_list *timer = &wd->timer; |
| |
| del_timer_sync(timer); |
| destroy_timer_on_stack(timer); |
| } |
| #else |
| #define DECLARE_DPM_WATCHDOG_ON_STACK(wd) |
| #define dpm_watchdog_set(x, y) |
| #define dpm_watchdog_clear(x) |
| #endif |
| |
| /*------------------------- Resume routines -------------------------*/ |
| |
| /** |
| * dev_pm_skip_resume - System-wide device resume optimization check. |
| * @dev: Target device. |
| * |
| * Return: |
| * - %false if the transition under way is RESTORE. |
| * - Return value of dev_pm_skip_suspend() if the transition under way is THAW. |
| * - The logical negation of %power.must_resume otherwise (that is, when the |
| * transition under way is RESUME). |
| */ |
| bool dev_pm_skip_resume(struct device *dev) |
| { |
| if (pm_transition.event == PM_EVENT_RESTORE) |
| return false; |
| |
| if (pm_transition.event == PM_EVENT_THAW) |
| return dev_pm_skip_suspend(dev); |
| |
| return !dev->power.must_resume; |
| } |
| |
| /** |
| * device_resume_noirq - Execute a "noirq resume" callback for given device. |
| * @dev: Device to handle. |
| * @state: PM transition of the system being carried out. |
| * @async: If true, the device is being resumed asynchronously. |
| * |
| * The driver of @dev will not receive interrupts while this function is being |
| * executed. |
| */ |
| static int device_resume_noirq(struct device *dev, pm_message_t state, bool async) |
| { |
| pm_callback_t callback = NULL; |
| const char *info = NULL; |
| bool skip_resume; |
| int error = 0; |
| |
| TRACE_DEVICE(dev); |
| TRACE_RESUME(0); |
| |
| if (dev->power.syscore || dev->power.direct_complete) |
| goto Out; |
| |
| if (!dev->power.is_noirq_suspended) |
| goto Out; |
| |
| if (!dpm_wait_for_superior(dev, async)) |
| goto Out; |
| |
| skip_resume = dev_pm_skip_resume(dev); |
| /* |
| * If the driver callback is skipped below or by the middle layer |
| * callback and device_resume_early() also skips the driver callback for |
| * this device later, it needs to appear as "suspended" to PM-runtime, |
| * so change its status accordingly. |
| * |
| * Otherwise, the device is going to be resumed, so set its PM-runtime |
| * status to "active", but do that only if DPM_FLAG_SMART_SUSPEND is set |
| * to avoid confusing drivers that don't use it. |
| */ |
| if (skip_resume) |
| pm_runtime_set_suspended(dev); |
| else if (dev_pm_skip_suspend(dev)) |
| pm_runtime_set_active(dev); |
| |
| if (dev->pm_domain) { |
| info = "noirq power domain "; |
| callback = pm_noirq_op(&dev->pm_domain->ops, state); |
| } else if (dev->type && dev->type->pm) { |
| info = "noirq type "; |
| callback = pm_noirq_op(dev->type->pm, state); |
| } else if (dev->class && dev->class->pm) { |
| info = "noirq class "; |
| callback = pm_noirq_op(dev->class->pm, state); |
| } else if (dev->bus && dev->bus->pm) { |
| info = "noirq bus "; |
| callback = pm_noirq_op(dev->bus->pm, state); |
| } |
| if (callback) |
| goto Run; |
| |
| if (skip_resume) |
| goto Skip; |
| |
| if (dev->driver && dev->driver->pm) { |
| info = "noirq driver "; |
| callback = pm_noirq_op(dev->driver->pm, state); |
| } |
| |
| Run: |
| error = dpm_run_callback(callback, dev, state, info); |
| |
| Skip: |
| dev->power.is_noirq_suspended = false; |
| |
| Out: |
| complete_all(&dev->power.completion); |
| TRACE_RESUME(error); |
| return error; |
| } |
| |
| static bool is_async(struct device *dev) |
| { |
| return dev->power.async_suspend && pm_async_enabled |
| && !pm_trace_is_enabled(); |
| } |
| |
| static bool dpm_async_fn(struct device *dev, async_func_t func) |
| { |
| reinit_completion(&dev->power.completion); |
| |
| if (is_async(dev)) { |
| get_device(dev); |
| async_schedule_dev(func, dev); |
| return true; |
| } |
| |
| return false; |
| } |
| |
| static void async_resume_noirq(void *data, async_cookie_t cookie) |
| { |
| struct device *dev = (struct device *)data; |
| int error; |
| |
| error = device_resume_noirq(dev, pm_transition, true); |
| if (error) |
| pm_dev_err(dev, pm_transition, " async", error); |
| |
| put_device(dev); |
| } |
| |
| static void dpm_noirq_resume_devices(pm_message_t state) |
| { |
| struct device *dev; |
| ktime_t starttime = ktime_get(); |
| |
| trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, true); |
| mutex_lock(&dpm_list_mtx); |
| pm_transition = state; |
| |
| /* |
| * Advanced the async threads upfront, |
| * in case the starting of async threads is |
| * delayed by non-async resuming devices. |
| */ |
| list_for_each_entry(dev, &dpm_noirq_list, power.entry) |
| dpm_async_fn(dev, async_resume_noirq); |
| |
| while (!list_empty(&dpm_noirq_list)) { |
| dev = to_device(dpm_noirq_list.next); |
| get_device(dev); |
| list_move_tail(&dev->power.entry, &dpm_late_early_list); |
| mutex_unlock(&dpm_list_mtx); |
| |
| if (!is_async(dev)) { |
| int error; |
| |
| error = device_resume_noirq(dev, state, false); |
| if (error) { |
| suspend_stats.failed_resume_noirq++; |
| dpm_save_failed_step(SUSPEND_RESUME_NOIRQ); |
| dpm_save_failed_dev(dev_name(dev)); |
| pm_dev_err(dev, state, " noirq", error); |
| } |
| } |
| |
| mutex_lock(&dpm_list_mtx); |
| put_device(dev); |
| } |
| mutex_unlock(&dpm_list_mtx); |
| async_synchronize_full(); |
| dpm_show_time(starttime, state, 0, "noirq"); |
| trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, false); |
| } |
| |
| /** |
| * dpm_resume_noirq - Execute "noirq resume" callbacks for all devices. |
| * @state: PM transition of the system being carried out. |
| * |
| * Invoke the "noirq" resume callbacks for all devices in dpm_noirq_list and |
| * allow device drivers' interrupt handlers to be called. |
| */ |
| void dpm_resume_noirq(pm_message_t state) |
| { |
| dpm_noirq_resume_devices(state); |
| |
| resume_device_irqs(); |
| device_wakeup_disarm_wake_irqs(); |
| |
| cpuidle_resume(); |
| } |
| |
| /** |
| * device_resume_early - Execute an "early resume" callback for given device. |
| * @dev: Device to handle. |
| * @state: PM transition of the system being carried out. |
| * @async: If true, the device is being resumed asynchronously. |
| * |
| * Runtime PM is disabled for @dev while this function is being executed. |
| */ |
| static int device_resume_early(struct device *dev, pm_message_t state, bool async) |
| { |
| pm_callback_t callback = NULL; |
| const char *info = NULL; |
| int error = 0; |
| |
| TRACE_DEVICE(dev); |
| TRACE_RESUME(0); |
| |
| if (dev->power.syscore || dev->power.direct_complete) |
| goto Out; |
| |
| if (!dev->power.is_late_suspended) |
| goto Out; |
| |
| if (!dpm_wait_for_superior(dev, async)) |
| goto Out; |
| |
| if (dev->pm_domain) { |
| info = "early power domain "; |
| callback = pm_late_early_op(&dev->pm_domain->ops, state); |
| } else if (dev->type && dev->type->pm) { |
| info = "early type "; |
| callback = pm_late_early_op(dev->type->pm, state); |
| } else if (dev->class && dev->class->pm) { |
| info = "early class "; |
| callback = pm_late_early_op(dev->class->pm, state); |
| } else if (dev->bus && dev->bus->pm) { |
| info = "early bus "; |
| callback = pm_late_early_op(dev->bus->pm, state); |
| } |
| if (callback) |
| goto Run; |
| |
| if (dev_pm_skip_resume(dev)) |
| goto Skip; |
| |
| if (dev->driver && dev->driver->pm) { |
| info = "early driver "; |
| callback = pm_late_early_op(dev->driver->pm, state); |
| } |
| |
| Run: |
| error = dpm_run_callback(callback, dev, state, info); |
| |
| Skip: |
| dev->power.is_late_suspended = false; |
| |
| Out: |
| TRACE_RESUME(error); |
| |
| pm_runtime_enable(dev); |
| complete_all(&dev->power.completion); |
| return error; |
| } |
| |
| static void async_resume_early(void *data, async_cookie_t cookie) |
| { |
| struct device *dev = (struct device *)data; |
| int error; |
| |
| error = device_resume_early(dev, pm_transition, true); |
| if (error) |
| pm_dev_err(dev, pm_transition, " async", error); |
| |
| put_device(dev); |
| } |
| |
| /** |
| * dpm_resume_early - Execute "early resume" callbacks for all devices. |
| * @state: PM transition of the system being carried out. |
| */ |
| void dpm_resume_early(pm_message_t state) |
| { |
| struct device *dev; |
| ktime_t starttime = ktime_get(); |
| |
| trace_suspend_resume(TPS("dpm_resume_early"), state.event, true); |
| mutex_lock(&dpm_list_mtx); |
| pm_transition = state; |
| |
| /* |
| * Advanced the async threads upfront, |
| * in case the starting of async threads is |
| * delayed by non-async resuming devices. |
| */ |
| list_for_each_entry(dev, &dpm_late_early_list, power.entry) |
| dpm_async_fn(dev, async_resume_early); |
| |
| while (!list_empty(&dpm_late_early_list)) { |
| dev = to_device(dpm_late_early_list.next); |
| get_device(dev); |
| list_move_tail(&dev->power.entry, &dpm_suspended_list); |
| mutex_unlock(&dpm_list_mtx); |
| |
| if (!is_async(dev)) { |
| int error; |
| |
| error = device_resume_early(dev, state, false); |
| if (error) { |
| suspend_stats.failed_resume_early++; |
| dpm_save_failed_step(SUSPEND_RESUME_EARLY); |
| dpm_save_failed_dev(dev_name(dev)); |
| pm_dev_err(dev, state, " early", error); |
| } |
| } |
| mutex_lock(&dpm_list_mtx); |
| put_device(dev); |
| } |
| mutex_unlock(&dpm_list_mtx); |
| async_synchronize_full(); |
| dpm_show_time(starttime, state, 0, "early"); |
| trace_suspend_resume(TPS("dpm_resume_early"), state.event, false); |
| } |
| |
| /** |
| * dpm_resume_start - Execute "noirq" and "early" device callbacks. |
| * @state: PM transition of the system being carried out. |
| */ |
| void dpm_resume_start(pm_message_t state) |
| { |
| dpm_resume_noirq(state); |
| dpm_resume_early(state); |
| } |
| EXPORT_SYMBOL_GPL(dpm_resume_start); |
| |
| /** |
| * device_resume - Execute "resume" callbacks for given device. |
| * @dev: Device to handle. |
| * @state: PM transition of the system being carried out. |
| * @async: If true, the device is being resumed asynchronously. |
| */ |
| static int device_resume(struct device *dev, pm_message_t state, bool async) |
| { |
| pm_callback_t callback = NULL; |
| const char *info = NULL; |
| int error = 0; |
| DECLARE_DPM_WATCHDOG_ON_STACK(wd); |
| |
| TRACE_DEVICE(dev); |
| TRACE_RESUME(0); |
| |
| if (dev->power.syscore) |
| goto Complete; |
| |
| if (dev->power.direct_complete) { |
| /* Match the pm_runtime_disable() in __device_suspend(). */ |
| pm_runtime_enable(dev); |
| goto Complete; |
| } |
| |
| if (!dpm_wait_for_superior(dev, async)) |
| goto Complete; |
| |
| dpm_watchdog_set(&wd, dev); |
| device_lock(dev); |
| |
| /* |
| * This is a fib. But we'll allow new children to be added below |
| * a resumed device, even if the device hasn't been completed yet. |
| */ |
| dev->power.is_prepared = false; |
| |
| if (!dev->power.is_suspended) |
| goto Unlock; |
| |
| if (dev->pm_domain) { |
| info = "power domain "; |
| callback = pm_op(&dev->pm_domain->ops, state); |
| goto Driver; |
| } |
| |
| if (dev->type && dev->type->pm) { |
| info = "type "; |
| callback = pm_op(dev->type->pm, state); |
| goto Driver; |
| } |
| |
| if (dev->class && dev->class->pm) { |
| info = "class "; |
| callback = pm_op(dev->class->pm, state); |
| goto Driver; |
| } |
| |
| if (dev->bus) { |
| if (dev->bus->pm) { |
| info = "bus "; |
| callback = pm_op(dev->bus->pm, state); |
| } else if (dev->bus->resume) { |
| info = "legacy bus "; |
| callback = dev->bus->resume; |
| goto End; |
| } |
| } |
| |
| Driver: |
| if (!callback && dev->driver && dev->driver->pm) { |
| info = "driver "; |
| callback = pm_op(dev->driver->pm, state); |
| } |
| |
| End: |
| error = dpm_run_callback(callback, dev, state, info); |
| dev->power.is_suspended = false; |
| |
| Unlock: |
| device_unlock(dev); |
| dpm_watchdog_clear(&wd); |
| |
| Complete: |
| complete_all(&dev->power.completion); |
| |
| TRACE_RESUME(error); |
| |
| return error; |
| } |
| |
| static void async_resume(void *data, async_cookie_t cookie) |
| { |
| struct device *dev = (struct device *)data; |
| int error; |
| |
| error = device_resume(dev, pm_transition, true); |
| if (error) |
| pm_dev_err(dev, pm_transition, " async", error); |
| put_device(dev); |
| } |
| |
| /** |
| * dpm_resume - Execute "resume" callbacks for non-sysdev devices. |
| * @state: PM transition of the system being carried out. |
| * |
| * Execute the appropriate "resume" callback for all devices whose status |
| * indicates that they are suspended. |
| */ |
| void dpm_resume(pm_message_t state) |
| { |
| struct device *dev; |
| ktime_t starttime = ktime_get(); |
| |
| trace_suspend_resume(TPS("dpm_resume"), state.event, true); |
| might_sleep(); |
| |
| mutex_lock(&dpm_list_mtx); |
| pm_transition = state; |
| async_error = 0; |
| |
| list_for_each_entry(dev, &dpm_suspended_list, power.entry) |
| dpm_async_fn(dev, async_resume); |
| |
| while (!list_empty(&dpm_suspended_list)) { |
| dev = to_device(dpm_suspended_list.next); |
| get_device(dev); |
| if (!is_async(dev)) { |
| int error; |
| |
| mutex_unlock(&dpm_list_mtx); |
| |
| error = device_resume(dev, state, false); |
| if (error) { |
| suspend_stats.failed_resume++; |
| dpm_save_failed_step(SUSPEND_RESUME); |
| dpm_save_failed_dev(dev_name(dev)); |
| pm_dev_err(dev, state, "", error); |
| } |
| |
| mutex_lock(&dpm_list_mtx); |
| } |
| if (!list_empty(&dev->power.entry)) |
| list_move_tail(&dev->power.entry, &dpm_prepared_list); |
| put_device(dev); |
| } |
| mutex_unlock(&dpm_list_mtx); |
| async_synchronize_full(); |
| dpm_show_time(starttime, state, 0, NULL); |
| |
| cpufreq_resume(); |
| devfreq_resume(); |
| trace_suspend_resume(TPS("dpm_resume"), state.event, false); |
| } |
| |
| /** |
| * device_complete - Complete a PM transition for given device. |
| * @dev: Device to handle. |
| * @state: PM transition of the system being carried out. |
| */ |
| static void device_complete(struct device *dev, pm_message_t state) |
| { |
| void (*callback)(struct device *) = NULL; |
| const char *info = NULL; |
| |
| if (dev->power.syscore) |
| return; |
| |
| device_lock(dev); |
| |
| if (dev->pm_domain) { |
| info = "completing power domain "; |
| callback = dev->pm_domain->ops.complete; |
| } else if (dev->type && dev->type->pm) { |
| info = "completing type "; |
| callback = dev->type->pm->complete; |
| } else if (dev->class && dev->class->pm) { |
| info = "completing class "; |
| callback = dev->class->pm->complete; |
| } else if (dev->bus && dev->bus->pm) { |
| info = "completing bus "; |
| callback = dev->bus->pm->complete; |
| } |
| |
| if (!callback && dev->driver && dev->driver->pm) { |
| info = "completing driver "; |
| callback = dev->driver->pm->complete; |
| } |
| |
| if (callback) { |
| pm_dev_dbg(dev, state, info); |
| callback(dev); |
| } |
| |
| device_unlock(dev); |
| |
| pm_runtime_put(dev); |
| } |
| |
| /** |
| * dpm_complete - Complete a PM transition for all non-sysdev devices. |
| * @state: PM transition of the system being carried out. |
| * |
| * Execute the ->complete() callbacks for all devices whose PM status is not |
| * DPM_ON (this allows new devices to be registered). |
| */ |
| void dpm_complete(pm_message_t state) |
| { |
| struct list_head list; |
| |
| trace_suspend_resume(TPS("dpm_complete"), state.event, true); |
| might_sleep(); |
| |
| INIT_LIST_HEAD(&list); |
| mutex_lock(&dpm_list_mtx); |
| while (!list_empty(&dpm_prepared_list)) { |
| struct device *dev = to_device(dpm_prepared_list.prev); |
| |
| get_device(dev); |
| dev->power.is_prepared = false; |
| list_move(&dev->power.entry, &list); |
| mutex_unlock(&dpm_list_mtx); |
| |
| trace_device_pm_callback_start(dev, "", state.event); |
| device_complete(dev, state); |
| trace_device_pm_callback_end(dev, 0); |
| |
| mutex_lock(&dpm_list_mtx); |
| put_device(dev); |
| } |
| list_splice(&list, &dpm_list); |
| mutex_unlock(&dpm_list_mtx); |
| |
| /* Allow device probing and trigger re-probing of deferred devices */ |
| device_unblock_probing(); |
| trace_suspend_resume(TPS("dpm_complete"), state.event, false); |
| } |
| |
| /** |
| * dpm_resume_end - Execute "resume" callbacks and complete system transition. |
| * @state: PM transition of the system being carried out. |
| * |
| * Execute "resume" callbacks for all devices and complete the PM transition of |
| * the system. |
| */ |
| void dpm_resume_end(pm_message_t state) |
| { |
| dpm_resume(state); |
| dpm_complete(state); |
| } |
| EXPORT_SYMBOL_GPL(dpm_resume_end); |
| |
| |
| /*------------------------- Suspend routines -------------------------*/ |
| |
| /** |
| * resume_event - Return a "resume" message for given "suspend" sleep state. |
| * @sleep_state: PM message representing a sleep state. |
| * |
| * Return a PM message representing the resume event corresponding to given |
| * sleep state. |
| */ |
| static pm_message_t resume_event(pm_message_t sleep_state) |
| { |
| switch (sleep_state.event) { |
| case PM_EVENT_SUSPEND: |
| return PMSG_RESUME; |
| case PM_EVENT_FREEZE: |
| case PM_EVENT_QUIESCE: |
| return PMSG_RECOVER; |
| case PM_EVENT_HIBERNATE: |
| return PMSG_RESTORE; |
| } |
| return PMSG_ON; |
| } |
| |
| static void dpm_superior_set_must_resume(struct device *dev) |
| { |
| struct device_link *link; |
| int idx; |
| |
| if (dev->parent) |
| dev->parent->power.must_resume = true; |
| |
| idx = device_links_read_lock(); |
| |
| list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) |
| link->supplier->power.must_resume = true; |
| |
| device_links_read_unlock(idx); |
| } |
| |
| /** |
| * __device_suspend_noirq - Execute a "noirq suspend" callback for given device. |
| * @dev: Device to handle. |
| * @state: PM transition of the system being carried out. |
| * @async: If true, the device is being suspended asynchronously. |
| * |
| * The driver of @dev will not receive interrupts while this function is being |
| * executed. |
| */ |
| static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool async) |
| { |
| pm_callback_t callback = NULL; |
| const char *info = NULL; |
| int error = 0; |
| |
| TRACE_DEVICE(dev); |
| TRACE_SUSPEND(0); |
| |
| dpm_wait_for_subordinate(dev, async); |
| |
| if (async_error) |
| goto Complete; |
| |
| if (dev->power.syscore || dev->power.direct_complete) |
| goto Complete; |
| |
| if (dev->pm_domain) { |
| info = "noirq power domain "; |
| callback = pm_noirq_op(&dev->pm_domain->ops, state); |
| } else if (dev->type && dev->type->pm) { |
| info = "noirq type "; |
| callback = pm_noirq_op(dev->type->pm, state); |
| } else if (dev->class && dev->class->pm) { |
| info = "noirq class "; |
| callback = pm_noirq_op(dev->class->pm, state); |
| } else if (dev->bus && dev->bus->pm) { |
| info = "noirq bus "; |
| callback = pm_noirq_op(dev->bus->pm, state); |
| } |
| if (callback) |
| goto Run; |
| |
| if (dev_pm_skip_suspend(dev)) |
| goto Skip; |
| |
| if (dev->driver && dev->driver->pm) { |
| info = "noirq driver "; |
| callback = pm_noirq_op(dev->driver->pm, state); |
| } |
| |
| Run: |
| error = dpm_run_callback(callback, dev, state, info); |
| if (error) { |
| async_error = error; |
| goto Complete; |
| } |
| |
| Skip: |
| dev->power.is_noirq_suspended = true; |
| |
| /* |
| * Skipping the resume of devices that were in use right before the |
| * system suspend (as indicated by their PM-runtime usage counters) |
| * would be suboptimal. Also resume them if doing that is not allowed |
| * to be skipped. |
| */ |
| if (atomic_read(&dev->power.usage_count) > 1 || |
| !(dev_pm_test_driver_flags(dev, DPM_FLAG_MAY_SKIP_RESUME) && |
| dev->power.may_skip_resume)) |
| dev->power.must_resume = true; |
| |
| if (dev->power.must_resume) |
| dpm_superior_set_must_resume(dev); |
| |
| Complete: |
| complete_all(&dev->power.completion); |
| TRACE_SUSPEND(error); |
| return error; |
| } |
| |
| static void async_suspend_noirq(void *data, async_cookie_t cookie) |
| { |
| struct device *dev = (struct device *)data; |
| int error; |
| |
| error = __device_suspend_noirq(dev, pm_transition, true); |
| if (error) { |
| dpm_save_failed_dev(dev_name(dev)); |
| pm_dev_err(dev, pm_transition, " async", error); |
| } |
| |
| put_device(dev); |
| } |
| |
| static int device_suspend_noirq(struct device *dev) |
| { |
| if (dpm_async_fn(dev, async_suspend_noirq)) |
| return 0; |
| |
| return __device_suspend_noirq(dev, pm_transition, false); |
| } |
| |
| static int dpm_noirq_suspend_devices(pm_message_t state) |
| { |
| ktime_t starttime = ktime_get(); |
| int error = 0; |
| |
| trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, true); |
| mutex_lock(&dpm_list_mtx); |
| pm_transition = state; |
| async_error = 0; |
| |
| while (!list_empty(&dpm_late_early_list)) { |
| struct device *dev = to_device(dpm_late_early_list.prev); |
| |
| get_device(dev); |
| mutex_unlock(&dpm_list_mtx); |
| |
| error = device_suspend_noirq(dev); |
| |
| mutex_lock(&dpm_list_mtx); |
| if (error) { |
| pm_dev_err(dev, state, " noirq", error); |
| dpm_save_failed_dev(dev_name(dev)); |
| put_device(dev); |
| break; |
| } |
| if (!list_empty(&dev->power.entry)) |
| list_move(&dev->power.entry, &dpm_noirq_list); |
| put_device(dev); |
| |
| if (async_error) |
| break; |
| } |
| mutex_unlock(&dpm_list_mtx); |
| async_synchronize_full(); |
| if (!error) |
| error = async_error; |
| |
| if (error) { |
| suspend_stats.failed_suspend_noirq++; |
| dpm_save_failed_step(SUSPEND_SUSPEND_NOIRQ); |
| } |
| dpm_show_time(starttime, state, error, "noirq"); |
| trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, false); |
| return error; |
| } |
| |
| /** |
| * dpm_suspend_noirq - Execute "noirq suspend" callbacks for all devices. |
| * @state: PM transition of the system being carried out. |
| * |
| * Prevent device drivers' interrupt handlers from being called and invoke |
| * "noirq" suspend callbacks for all non-sysdev devices. |
| */ |
| int dpm_suspend_noirq(pm_message_t state) |
| { |
| int ret; |
| |
| cpuidle_pause(); |
| |
| device_wakeup_arm_wake_irqs(); |
| suspend_device_irqs(); |
| |
| ret = dpm_noirq_suspend_devices(state); |
| if (ret) |
| dpm_resume_noirq(resume_event(state)); |
| |
| return ret; |
| } |
| |
| static void dpm_propagate_wakeup_to_parent(struct device *dev) |
| { |
| struct device *parent = dev->parent; |
| |
| if (!parent) |
| return; |
| |
| spin_lock_irq(&parent->power.lock); |
| |
| if (dev->power.wakeup_path && !parent->power.ignore_children) |
| parent->power.wakeup_path = true; |
| |
| spin_unlock_irq(&parent->power.lock); |
| } |
| |
| /** |
| * __device_suspend_late - Execute a "late suspend" callback for given device. |
| * @dev: Device to handle. |
| * @state: PM transition of the system being carried out. |
| * @async: If true, the device is being suspended asynchronously. |
| * |
| * Runtime PM is disabled for @dev while this function is being executed. |
| */ |
| static int __device_suspend_late(struct device *dev, pm_message_t state, bool async) |
| { |
| pm_callback_t callback = NULL; |
| const char *info = NULL; |
| int error = 0; |
| |
| TRACE_DEVICE(dev); |
| TRACE_SUSPEND(0); |
| |
| __pm_runtime_disable(dev, false); |
| |
| dpm_wait_for_subordinate(dev, async); |
| |
| if (async_error) |
| goto Complete; |
| |
| if (pm_wakeup_pending()) { |
| async_error = -EBUSY; |
| goto Complete; |
| } |
| |
| if (dev->power.syscore || dev->power.direct_complete) |
| goto Complete; |
| |
| if (dev->pm_domain) { |
| info = "late power domain "; |
| callback = pm_late_early_op(&dev->pm_domain->ops, state); |
| } else if (dev->type && dev->type->pm) { |
| info = "late type "; |
| callback = pm_late_early_op(dev->type->pm, state); |
| } else if (dev->class && dev->class->pm) { |
| info = "late class "; |
| callback = pm_late_early_op(dev->class->pm, state); |
| } else if (dev->bus && dev->bus->pm) { |
| info = "late bus "; |
| callback = pm_late_early_op(dev->bus->pm, state); |
| } |
| if (callback) |
| goto Run; |
| |
| if (dev_pm_skip_suspend(dev)) |
| goto Skip; |
| |
| if (dev->driver && dev->driver->pm) { |
| info = "late driver "; |
| callback = pm_late_early_op(dev->driver->pm, state); |
| } |
| |
| Run: |
| error = dpm_run_callback(callback, dev, state, info); |
| if (error) { |
| async_error = error; |
| goto Complete; |
| } |
| dpm_propagate_wakeup_to_parent(dev); |
| |
| Skip: |
| dev->power.is_late_suspended = true; |
| |
| Complete: |
| TRACE_SUSPEND(error); |
| complete_all(&dev->power.completion); |
| return error; |
| } |
| |
| static void async_suspend_late(void *data, async_cookie_t cookie) |
| { |
| struct device *dev = (struct device *)data; |
| int error; |
| |
| error = __device_suspend_late(dev, pm_transition, true); |
| if (error) { |
| dpm_save_failed_dev(dev_name(dev)); |
| pm_dev_err(dev, pm_transition, " async", error); |
| } |
| put_device(dev); |
| } |
| |
| static int device_suspend_late(struct device *dev) |
| { |
| if (dpm_async_fn(dev, async_suspend_late)) |
| return 0; |
| |
| return __device_suspend_late(dev, pm_transition, false); |
| } |
| |
| /** |
| * dpm_suspend_late - Execute "late suspend" callbacks for all devices. |
| * @state: PM transition of the system being carried out. |
| */ |
| int dpm_suspend_late(pm_message_t state) |
| { |
| ktime_t starttime = ktime_get(); |
| int error = 0; |
| |
| trace_suspend_resume(TPS("dpm_suspend_late"), state.event, true); |
| mutex_lock(&dpm_list_mtx); |
| pm_transition = state; |
| async_error = 0; |
| |
| while (!list_empty(&dpm_suspended_list)) { |
| struct device *dev = to_device(dpm_suspended_list.prev); |
| |
| get_device(dev); |
| mutex_unlock(&dpm_list_mtx); |
| |
| error = device_suspend_late(dev); |
| |
| mutex_lock(&dpm_list_mtx); |
| if (!list_empty(&dev->power.entry)) |
| list_move(&dev->power.entry, &dpm_late_early_list); |
| |
| if (error) { |
| pm_dev_err(dev, state, " late", error); |
| dpm_save_failed_dev(dev_name(dev)); |
| put_device(dev); |
| break; |
| } |
| put_device(dev); |
| |
| if (async_error) |
| break; |
| } |
| mutex_unlock(&dpm_list_mtx); |
| async_synchronize_full(); |
| if (!error) |
| error = async_error; |
| if (error) { |
| suspend_stats.failed_suspend_late++; |
| dpm_save_failed_step(SUSPEND_SUSPEND_LATE); |
| dpm_resume_early(resume_event(state)); |
| } |
| dpm_show_time(starttime, state, error, "late"); |
| trace_suspend_resume(TPS("dpm_suspend_late"), state.event, false); |
| return error; |
| } |
| |
| /** |
| * dpm_suspend_end - Execute "late" and "noirq" device suspend callbacks. |
| * @state: PM transition of the system being carried out. |
| */ |
| int dpm_suspend_end(pm_message_t state) |
| { |
| ktime_t starttime = ktime_get(); |
| int error; |
| |
| error = dpm_suspend_late(state); |
| if (error) |
| goto out; |
| |
| error = dpm_suspend_noirq(state); |
| if (error) |
| dpm_resume_early(resume_event(state)); |
| |
| out: |
| dpm_show_time(starttime, state, error, "end"); |
| return error; |
| } |
| EXPORT_SYMBOL_GPL(dpm_suspend_end); |
| |
| /** |
| * legacy_suspend - Execute a legacy (bus or class) suspend callback for device. |
| * @dev: Device to suspend. |
| * @state: PM transition of the system being carried out. |
| * @cb: Suspend callback to execute. |
| * @info: string description of caller. |
| */ |
| static int legacy_suspend(struct device *dev, pm_message_t state, |
| int (*cb)(struct device *dev, pm_message_t state), |
| const char *info) |
| { |
| int error; |
| ktime_t calltime; |
| |
| calltime = initcall_debug_start(dev, cb); |
| |
| trace_device_pm_callback_start(dev, info, state.event); |
| error = cb(dev, state); |
| trace_device_pm_callback_end(dev, error); |
| suspend_report_result(cb, error); |
| |
| initcall_debug_report(dev, calltime, cb, error); |
| |
| return error; |
| } |
| |
| static void dpm_clear_superiors_direct_complete(struct device *dev) |
| { |
| struct device_link *link; |
| int idx; |
| |
| if (dev->parent) { |
| spin_lock_irq(&dev->parent->power.lock); |
| dev->parent->power.direct_complete = false; |
| spin_unlock_irq(&dev->parent->power.lock); |
| } |
| |
| idx = device_links_read_lock(); |
| |
| list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) { |
| spin_lock_irq(&link->supplier->power.lock); |
| link->supplier->power.direct_complete = false; |
| spin_unlock_irq(&link->supplier->power.lock); |
| } |
| |
| device_links_read_unlock(idx); |
| } |
| |
| /** |
| * __device_suspend - Execute "suspend" callbacks for given device. |
| * @dev: Device to handle. |
| * @state: PM transition of the system being carried out. |
| * @async: If true, the device is being suspended asynchronously. |
| */ |
| static int __device_suspend(struct device *dev, pm_message_t state, bool async) |
| { |
| pm_callback_t callback = NULL; |
| const char *info = NULL; |
| int error = 0; |
| DECLARE_DPM_WATCHDOG_ON_STACK(wd); |
| |
| TRACE_DEVICE(dev); |
| TRACE_SUSPEND(0); |
| |
| dpm_wait_for_subordinate(dev, async); |
| |
| if (async_error) { |
| dev->power.direct_complete = false; |
| goto Complete; |
| } |
| |
| /* |
| * If a device configured to wake up the system from sleep states |
| * has been suspended at run time and there's a resume request pending |
| * for it, this is equivalent to the device signaling wakeup, so the |
| * system suspend operation should be aborted. |
| */ |
| if (pm_runtime_barrier(dev) && device_may_wakeup(dev)) |
| pm_wakeup_event(dev, 0); |
| |
| if (pm_wakeup_pending()) { |
| dev->power.direct_complete = false; |
| async_error = -EBUSY; |
| goto Complete; |
| } |
| |
| if (dev->power.syscore) |
| goto Complete; |
| |
| /* Avoid direct_complete to let wakeup_path propagate. */ |
| if (device_may_wakeup(dev) || dev->power.wakeup_path) |
| dev->power.direct_complete = false; |
| |
| if (dev->power.direct_complete) { |
| if (pm_runtime_status_suspended(dev)) { |
| pm_runtime_disable(dev); |
| if (pm_runtime_status_suspended(dev)) { |
| pm_dev_dbg(dev, state, "direct-complete "); |
| goto Complete; |
| } |
| |
| pm_runtime_enable(dev); |
| } |
| dev->power.direct_complete = false; |
| } |
| |
| dev->power.may_skip_resume = true; |
| dev->power.must_resume = false; |
| |
| dpm_watchdog_set(&wd, dev); |
| device_lock(dev); |
| |
| if (dev->pm_domain) { |
| info = "power domain "; |
| callback = pm_op(&dev->pm_domain->ops, state); |
| goto Run; |
| } |
| |
| if (dev->type && dev->type->pm) { |
| info = "type "; |
| callback = pm_op(dev->type->pm, state); |
| goto Run; |
| } |
| |
| if (dev->class && dev->class->pm) { |
| info = "class "; |
| callback = pm_op(dev->class->pm, state); |
| goto Run; |
| } |
| |
| if (dev->bus) { |
| if (dev->bus->pm) { |
| info = "bus "; |
| callback = pm_op(dev->bus->pm, state); |
| } else if (dev->bus->suspend) { |
| pm_dev_dbg(dev, state, "legacy bus "); |
| error = legacy_suspend(dev, state, dev->bus->suspend, |
| "legacy bus "); |
| goto End; |
| } |
| } |
| |
| Run: |
| if (!callback && dev->driver && dev->driver->pm) { |
| info = "driver "; |
| callback = pm_op(dev->driver->pm, state); |
| } |
| |
| error = dpm_run_callback(callback, dev, state, info); |
| |
| End: |
| if (!error) { |
| dev->power.is_suspended = true; |
| if (device_may_wakeup(dev)) |
| dev->power.wakeup_path = true; |
| |
| dpm_propagate_wakeup_to_parent(dev); |
| dpm_clear_superiors_direct_complete(dev); |
| } |
| |
| device_unlock(dev); |
| dpm_watchdog_clear(&wd); |
| |
| Complete: |
| if (error) |
| async_error = error; |
| |
| complete_all(&dev->power.completion); |
| TRACE_SUSPEND(error); |
| return error; |
| } |
| |
| static void async_suspend(void *data, async_cookie_t cookie) |
| { |
| struct device *dev = (struct device *)data; |
| int error; |
| |
| error = __device_suspend(dev, pm_transition, true); |
| if (error) { |
| dpm_save_failed_dev(dev_name(dev)); |
| pm_dev_err(dev, pm_transition, " async", error); |
| } |
| |
| put_device(dev); |
| } |
| |
| static int device_suspend(struct device *dev) |
| { |
| if (dpm_async_fn(dev, async_suspend)) |
| return 0; |
| |
| return __device_suspend(dev, pm_transition, false); |
| } |
| |
| /** |
| * dpm_suspend - Execute "suspend" callbacks for all non-sysdev devices. |
| * @state: PM transition of the system being carried out. |
| */ |
| int dpm_suspend(pm_message_t state) |
| { |
| ktime_t starttime = ktime_get(); |
| int error = 0; |
| |
| trace_suspend_resume(TPS("dpm_suspend"), state.event, true); |
| might_sleep(); |
| |
| devfreq_suspend(); |
| cpufreq_suspend(); |
| |
| mutex_lock(&dpm_list_mtx); |
| pm_transition = state; |
| async_error = 0; |
| while (!list_empty(&dpm_prepared_list)) { |
| struct device *dev = to_device(dpm_prepared_list.prev); |
| |
| get_device(dev); |
| mutex_unlock(&dpm_list_mtx); |
| |
| error = device_suspend(dev); |
| |
| mutex_lock(&dpm_list_mtx); |
| if (error) { |
| pm_dev_err(dev, state, "", error); |
| dpm_save_failed_dev(dev_name(dev)); |
| put_device(dev); |
| break; |
| } |
| if (!list_empty(&dev->power.entry)) |
| list_move(&dev->power.entry, &dpm_suspended_list); |
| put_device(dev); |
| if (async_error) |
| break; |
| } |
| mutex_unlock(&dpm_list_mtx); |
| async_synchronize_full(); |
| if (!error) |
| error = async_error; |
| if (error) { |
| suspend_stats.failed_suspend++; |
| dpm_save_failed_step(SUSPEND_SUSPEND); |
| } |
| dpm_show_time(starttime, state, error, NULL); |
| trace_suspend_resume(TPS("dpm_suspend"), state.event, false); |
| return error; |
| } |
| |
| /** |
| * device_prepare - Prepare a device for system power transition. |
| * @dev: Device to handle. |
| * @state: PM transition of the system being carried out. |
| * |
| * Execute the ->prepare() callback(s) for given device. No new children of the |
| * device may be registered after this function has returned. |
| */ |
| static int device_prepare(struct device *dev, pm_message_t state) |
| { |
| int (*callback)(struct device *) = NULL; |
| int ret = 0; |
| |
| if (dev->power.syscore) |
| return 0; |
| |
| /* |
| * If a device's parent goes into runtime suspend at the wrong time, |
| * it won't be possible to resume the device. To prevent this we |
| * block runtime suspend here, during the prepare phase, and allow |
| * it again during the complete phase. |
| */ |
| pm_runtime_get_noresume(dev); |
| |
| device_lock(dev); |
| |
| dev->power.wakeup_path = false; |
| |
| if (dev->power.no_pm_callbacks) |
| goto unlock; |
| |
| if (dev->pm_domain) |
| callback = dev->pm_domain->ops.prepare; |
| else if (dev->type && dev->type->pm) |
| callback = dev->type->pm->prepare; |
| else if (dev->class && dev->class->pm) |
| callback = dev->class->pm->prepare; |
| else if (dev->bus && dev->bus->pm) |
| callback = dev->bus->pm->prepare; |
| |
| if (!callback && dev->driver && dev->driver->pm) |
| callback = dev->driver->pm->prepare; |
| |
| if (callback) |
| ret = callback(dev); |
| |
| unlock: |
| device_unlock(dev); |
| |
| if (ret < 0) { |
| suspend_report_result(callback, ret); |
| pm_runtime_put(dev); |
| return ret; |
| } |
| /* |
| * A positive return value from ->prepare() means "this device appears |
| * to be runtime-suspended and its state is fine, so if it really is |
| * runtime-suspended, you can leave it in that state provided that you |
| * will do the same thing with all of its descendants". This only |
| * applies to suspend transitions, however. |
| */ |
| spin_lock_irq(&dev->power.lock); |
| dev->power.direct_complete = state.event == PM_EVENT_SUSPEND && |
| (ret > 0 || dev->power.no_pm_callbacks) && |
| !dev_pm_test_driver_flags(dev, DPM_FLAG_NO_DIRECT_COMPLETE); |
| spin_unlock_irq(&dev->power.lock); |
| return 0; |
| } |
| |
| /** |
| * dpm_prepare - Prepare all non-sysdev devices for a system PM transition. |
| * @state: PM transition of the system being carried out. |
| * |
| * Execute the ->prepare() callback(s) for all devices. |
| */ |
| int dpm_prepare(pm_message_t state) |
| { |
| int error = 0; |
| |
| trace_suspend_resume(TPS("dpm_prepare"), state.event, true); |
| might_sleep(); |
| |
| /* |
| * Give a chance for the known devices to complete their probes, before |
| * disable probing of devices. This sync point is important at least |
| * at boot time + hibernation restore. |
| */ |
| wait_for_device_probe(); |
| /* |
| * It is unsafe if probing of devices will happen during suspend or |
| * hibernation and system behavior will be unpredictable in this case. |
| * So, let's prohibit device's probing here and defer their probes |
| * instead. The normal behavior will be restored in dpm_complete(). |
| */ |
| device_block_probing(); |
| |
| mutex_lock(&dpm_list_mtx); |
| while (!list_empty(&dpm_list)) { |
| struct device *dev = to_device(dpm_list.next); |
| |
| get_device(dev); |
| mutex_unlock(&dpm_list_mtx); |
| |
| trace_device_pm_callback_start(dev, "", state.event); |
| error = device_prepare(dev, state); |
| trace_device_pm_callback_end(dev, error); |
| |
| mutex_lock(&dpm_list_mtx); |
| if (error) { |
| if (error == -EAGAIN) { |
| put_device(dev); |
| error = 0; |
| continue; |
| } |
| pr_info("Device %s not prepared for power transition: code %d\n", |
| dev_name(dev), error); |
| put_device(dev); |
| break; |
| } |
| dev->power.is_prepared = true; |
| if (!list_empty(&dev->power.entry)) |
| list_move_tail(&dev->power.entry, &dpm_prepared_list); |
| put_device(dev); |
| } |
| mutex_unlock(&dpm_list_mtx); |
| trace_suspend_resume(TPS("dpm_prepare"), state.event, false); |
| return error; |
| } |
| |
| /** |
| * dpm_suspend_start - Prepare devices for PM transition and suspend them. |
| * @state: PM transition of the system being carried out. |
| * |
| * Prepare all non-sysdev devices for system PM transition and execute "suspend" |
| * callbacks for them. |
| */ |
| int dpm_suspend_start(pm_message_t state) |
| { |
| ktime_t starttime = ktime_get(); |
| int error; |
| |
| error = dpm_prepare(state); |
| if (error) { |
| suspend_stats.failed_prepare++; |
| dpm_save_failed_step(SUSPEND_PREPARE); |
| } else |
| error = dpm_suspend(state); |
| dpm_show_time(starttime, state, error, "start"); |
| return error; |
| } |
| EXPORT_SYMBOL_GPL(dpm_suspend_start); |
| |
| void __suspend_report_result(const char *function, void *fn, int ret) |
| { |
| if (ret) |
| pr_err("%s(): %pS returns %d\n", function, fn, ret); |
| } |
| EXPORT_SYMBOL_GPL(__suspend_report_result); |
| |
| /** |
| * device_pm_wait_for_dev - Wait for suspend/resume of a device to complete. |
| * @subordinate: Device that needs to wait for @dev. |
| * @dev: Device to wait for. |
| */ |
| int device_pm_wait_for_dev(struct device *subordinate, struct device *dev) |
| { |
| dpm_wait(dev, subordinate->power.async_suspend); |
| return async_error; |
| } |
| EXPORT_SYMBOL_GPL(device_pm_wait_for_dev); |
| |
| /** |
| * dpm_for_each_dev - device iterator. |
| * @data: data for the callback. |
| * @fn: function to be called for each device. |
| * |
| * Iterate over devices in dpm_list, and call @fn for each device, |
| * passing it @data. |
| */ |
| void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *)) |
| { |
| struct device *dev; |
| |
| if (!fn) |
| return; |
| |
| device_pm_lock(); |
| list_for_each_entry(dev, &dpm_list, power.entry) |
| fn(dev, data); |
| device_pm_unlock(); |
| } |
| EXPORT_SYMBOL_GPL(dpm_for_each_dev); |
| |
| static bool pm_ops_is_empty(const struct dev_pm_ops *ops) |
| { |
| if (!ops) |
| return true; |
| |
| return !ops->prepare && |
| !ops->suspend && |
| !ops->suspend_late && |
| !ops->suspend_noirq && |
| !ops->resume_noirq && |
| !ops->resume_early && |
| !ops->resume && |
| !ops->complete; |
| } |
| |
| void device_pm_check_callbacks(struct device *dev) |
| { |
| spin_lock_irq(&dev->power.lock); |
| dev->power.no_pm_callbacks = |
| (!dev->bus || (pm_ops_is_empty(dev->bus->pm) && |
| !dev->bus->suspend && !dev->bus->resume)) && |
| (!dev->class || pm_ops_is_empty(dev->class->pm)) && |
| (!dev->type || pm_ops_is_empty(dev->type->pm)) && |
| (!dev->pm_domain || pm_ops_is_empty(&dev->pm_domain->ops)) && |
| (!dev->driver || (pm_ops_is_empty(dev->driver->pm) && |
| !dev->driver->suspend && !dev->driver->resume)); |
| spin_unlock_irq(&dev->power.lock); |
| } |
| |
| bool dev_pm_skip_suspend(struct device *dev) |
| { |
| return dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) && |
| pm_runtime_status_suspended(dev); |
| } |