| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Rafael J. Wysocki | 5283 | 65.47% | 80 | 49.69% |
| Chuansheng Liu | 590 | 7.31% | 5 | 3.11% |
| Todd E Brandt | 296 | 3.67% | 3 | 1.86% |
| Alan Stern | 258 | 3.20% | 8 | 4.97% |
| Benoit Goby | 235 | 2.91% | 1 | 0.62% |
| Tomeu Vizoso | 199 | 2.47% | 1 | 0.62% |
| Cornelia Huck | 181 | 2.24% | 1 | 0.62% |
| Ulf Hansson | 157 | 1.95% | 7 | 4.35% |
| Patrick Mochel | 97 | 1.20% | 2 | 1.24% |
| Liu ShuoX | 92 | 1.14% | 1 | 0.62% |
| Dominik Brodowski | 84 | 1.04% | 1 | 0.62% |
| Shuah Khan | 79 | 0.98% | 1 | 0.62% |
| Yangtao Li | 67 | 0.83% | 3 | 1.86% |
| Ming Lei | 61 | 0.76% | 1 | 0.62% |
| Bart Van Assche | 43 | 0.53% | 1 | 0.62% |
| Björn Helgaas | 40 | 0.50% | 3 | 1.86% |
| Colin Cross | 28 | 0.35% | 2 | 1.24% |
| Fu Zhonghui | 26 | 0.32% | 1 | 0.62% |
| Arjan van de Ven | 17 | 0.21% | 1 | 0.62% |
| Sudeep Holla | 17 | 0.21% | 1 | 0.62% |
| Kees Cook | 17 | 0.21% | 1 | 0.62% |
| Madhuparna Bhowmik | 16 | 0.20% | 1 | 0.62% |
| Youngjin Jang | 14 | 0.17% | 1 | 0.62% |
| Joe Perches | 12 | 0.15% | 1 | 0.62% |
| Krzysztof Kozlowski | 12 | 0.15% | 2 | 1.24% |
| Grygorii Strashko | 12 | 0.15% | 1 | 0.62% |
| Matthias Kaehlcke | 11 | 0.14% | 1 | 0.62% |
| Dmitry Eremin-Solenikov | 10 | 0.12% | 1 | 0.62% |
| Lukasz Luba | 9 | 0.11% | 1 | 0.62% |
| Imre Deak | 9 | 0.11% | 1 | 0.62% |
| Viresh Kumar | 9 | 0.11% | 1 | 0.62% |
| Sahitya Tummala | 8 | 0.10% | 1 | 0.62% |
| Mandeep Singh Baines | 8 | 0.10% | 1 | 0.62% |
| Chen Yu | 7 | 0.09% | 1 | 0.62% |
| Prasad Sodagudi | 7 | 0.09% | 1 | 0.62% |
| Mark-PK Tsai | 6 | 0.07% | 1 | 0.62% |
| Patrice Chotard | 6 | 0.07% | 1 | 0.62% |
| Greg Kroah-Hartman | 5 | 0.06% | 2 | 1.24% |
| Dmitry Torokhov | 5 | 0.06% | 2 | 1.24% |
| Andrew Morton | 4 | 0.05% | 1 | 0.62% |
| Sachin Kamat | 4 | 0.05% | 1 | 0.62% |
| Tony Lindgren | 3 | 0.04% | 1 | 0.62% |
| Ingo Molnar | 3 | 0.04% | 1 | 0.62% |
| Feng Hong | 3 | 0.04% | 1 | 0.62% |
| Kay Sievers | 3 | 0.04% | 1 | 0.62% |
| Sakari Ailus | 3 | 0.04% | 1 | 0.62% |
| Paul Gortmaker | 3 | 0.04% | 1 | 0.62% |
| Jean Pihet | 3 | 0.04% | 1 | 0.62% |
| Dmitry Safonov | 3 | 0.04% | 2 | 1.24% |
| Kai-Heng Feng | 1 | 0.01% | 1 | 0.62% |
| Adrian Bunk | 1 | 0.01% | 1 | 0.62% |
| Kevin Cernekee | 1 | 0.01% | 1 | 0.62% |
| Randy Dunlap | 1 | 0.01% | 1 | 0.62% |
| Total | 8069 | 161 |
// 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 #define dev_fmt pr_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/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; if (!pm_print_times_enabled) return; rettime = ktime_get(); dev_info(dev, "%pS returned %d after %Ld usecs\n", cb, error, (unsigned long long)ktime_us_delta(rettime, calltime)); } /** * 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; 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 driver flags: %x\n", info, pm_verb(state.event), ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ? ", may wakeup" : "", dev->power.driver_flags); } static void pm_dev_err(struct device *dev, pm_message_t state, const char *info, int error) { dev_err(dev, "failed to %s%s: error %d\n", 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(dev, 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); } } put_device(dev); mutex_lock(&dpm_list_mtx); } 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(); } /** * 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); } } put_device(dev); mutex_lock(&dpm_list_mtx); } 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); mutex_unlock(&dpm_list_mtx); put_device(dev); mutex_lock(&dpm_list_mtx); } 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) goto out; 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); out: 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); put_device(dev); mutex_lock(&dpm_list_mtx); } 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)); } else if (!list_empty(&dev->power.entry)) { list_move(&dev->power.entry, &dpm_noirq_list); } mutex_unlock(&dpm_list_mtx); put_device(dev); mutex_lock(&dpm_list_mtx); if (error || 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; 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 (device_wakeup_path(dev) && !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); wake_up_all_idle_cpus(); 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)); } mutex_unlock(&dpm_list_mtx); put_device(dev); mutex_lock(&dpm_list_mtx); if (error || 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(dev, 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; } /* * Wait for possible runtime PM transitions of the device in progress * to complete and if there's a runtime resume request pending for it, * resume it before proceeding with invoking the system-wide suspend * callbacks for it. * * If the system-wide suspend callbacks below change the configuration * of the device, they must disable runtime PM for it or otherwise * ensure that its runtime-resume callbacks will not be confused by that * change in case they are invoked going forward. */ pm_runtime_barrier(dev); 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) || device_wakeup_path(dev)) 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 = !dev_pm_test_driver_flags(dev, DPM_FLAG_MAY_SKIP_RESUME); 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)); } else if (!list_empty(&dev->power.entry)) { list_move(&dev->power.entry, &dpm_suspended_list); } mutex_unlock(&dpm_list_mtx); put_device(dev); mutex_lock(&dpm_list_mtx); if (error || 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 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); if (dev->power.syscore) return 0; 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(dev, 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) && !error) { 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) { dev->power.is_prepared = true; if (!list_empty(&dev->power.entry)) list_move_tail(&dev->power.entry, &dpm_prepared_list); } else if (error == -EAGAIN) { error = 0; } else { dev_info(dev, "not prepared for power transition: code %d\n", error); } mutex_unlock(&dpm_list_mtx); put_device(dev); mutex_lock(&dpm_list_mtx); } 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, struct device *dev, void *fn, int ret) { if (ret) dev_err(dev, "%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) { unsigned long flags; spin_lock_irqsave(&dev->power.lock, flags); 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_irqrestore(&dev->power.lock, flags); } bool dev_pm_skip_suspend(struct device *dev) { return dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) && pm_runtime_status_suspended(dev); }
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with Cregit http://github.com/cregit/cregit
Version 2.0-RC1