diff options
Diffstat (limited to 'drivers/base')
| -rw-r--r-- | drivers/base/power/main.c | 242 | ||||
| -rw-r--r-- | drivers/base/power/power.h | 6 | ||||
| -rw-r--r-- | drivers/base/power/sysfs.c | 47 |
3 files changed, 266 insertions, 29 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 1a216c114a0f..2869a4865369 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -25,6 +25,7 @@ #include <linux/resume-trace.h> #include <linux/interrupt.h> #include <linux/sched.h> +#include <linux/async.h> #include "../base.h" #include "power.h" @@ -42,6 +43,7 @@ LIST_HEAD(dpm_list); static DEFINE_MUTEX(dpm_list_mtx); +static pm_message_t pm_transition; /* * Set once the preparation of devices for a PM transition has started, reset @@ -56,6 +58,7 @@ static bool transition_started; void device_pm_init(struct device *dev) { dev->power.status = DPM_ON; + init_completion(&dev->power.completion); pm_runtime_init(dev); } @@ -111,6 +114,7 @@ void device_pm_remove(struct device *dev) pr_debug("PM: Removing info for %s:%s\n", dev->bus ? dev->bus->name : "No Bus", kobject_name(&dev->kobj)); + complete_all(&dev->power.completion); mutex_lock(&dpm_list_mtx); list_del_init(&dev->power.entry); mutex_unlock(&dpm_list_mtx); @@ -161,6 +165,57 @@ void device_pm_move_last(struct device *dev) list_move_tail(&dev->power.entry, &dpm_list); } +static ktime_t initcall_debug_start(struct device *dev) +{ + ktime_t calltime = ktime_set(0, 0); + + if (initcall_debug) { + pr_info("calling %s+ @ %i\n", + dev_name(dev), task_pid_nr(current)); + calltime = ktime_get(); + } + + return calltime; +} + +static void initcall_debug_report(struct device *dev, ktime_t calltime, + int error) +{ + ktime_t delta, rettime; + + if (initcall_debug) { + rettime = ktime_get(); + delta = ktime_sub(rettime, calltime); + pr_info("call %s+ returned %d after %Ld usecs\n", dev_name(dev), + error, (unsigned long long)ktime_to_ns(delta) >> 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); +} + /** * pm_op - Execute the PM operation appropriate for given PM event. * @dev: Device to handle. @@ -172,13 +227,9 @@ static int pm_op(struct device *dev, pm_message_t state) { int error = 0; - ktime_t calltime, delta, rettime; + ktime_t calltime; - if (initcall_debug) { - pr_info("calling %s+ @ %i\n", - dev_name(dev), task_pid_nr(current)); - calltime = ktime_get(); - } + calltime = initcall_debug_start(dev); switch (state.event) { #ifdef CONFIG_SUSPEND @@ -227,12 +278,7 @@ static int pm_op(struct device *dev, error = -EINVAL; } - if (initcall_debug) { - rettime = ktime_get(); - delta = ktime_sub(rettime, calltime); - pr_info("call %s+ returned %d after %Ld usecs\n", dev_name(dev), - error, (unsigned long long)ktime_to_ns(delta) >> 10); - } + initcall_debug_report(dev, calltime, error); return error; } @@ -309,8 +355,9 @@ static int pm_noirq_op(struct device *dev, if (initcall_debug) { rettime = ktime_get(); delta = ktime_sub(rettime, calltime); - printk("initcall %s_i+ returned %d after %Ld usecs\n", dev_name(dev), - error, (unsigned long long)ktime_to_ns(delta) >> 10); + printk("initcall %s_i+ returned %d after %Ld usecs\n", + dev_name(dev), error, + (unsigned long long)ktime_to_ns(delta) >> 10); } return error; @@ -354,6 +401,23 @@ static void pm_dev_err(struct device *dev, pm_message_t state, char *info, kobject_name(&dev->kobj), pm_verb(state.event), info, error); } +static void dpm_show_time(ktime_t starttime, pm_message_t state, char *info) +{ + ktime_t calltime; + s64 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; + pr_info("PM: %s%s%s of devices complete after %ld.%03ld msecs\n", + info ?: "", info ? " " : "", pm_verb(state.event), + usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC); +} + /*------------------------- Resume routines -------------------------*/ /** @@ -390,6 +454,7 @@ static int device_resume_noirq(struct device *dev, pm_message_t state) void dpm_resume_noirq(pm_message_t state) { struct device *dev; + ktime_t starttime = ktime_get(); mutex_lock(&dpm_list_mtx); transition_started = false; @@ -403,22 +468,45 @@ void dpm_resume_noirq(pm_message_t state) pm_dev_err(dev, state, " early", error); } mutex_unlock(&dpm_list_mtx); + dpm_show_time(starttime, state, "early"); resume_device_irqs(); } EXPORT_SYMBOL_GPL(dpm_resume_noirq); /** - * device_resume - Execute "resume" callbacks for given device. + * legacy_resume - Execute a legacy (bus or class) resume callback for device. + * dev: Device to resume. + * cb: Resume callback to execute. + */ +static int legacy_resume(struct device *dev, int (*cb)(struct device *dev)) +{ + int error; + ktime_t calltime; + + calltime = initcall_debug_start(dev); + + error = cb(dev); + suspend_report_result(cb, error); + + initcall_debug_report(dev, calltime, error); + + return error; +} + +/** + * __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) +static int __device_resume(struct device *dev, pm_message_t state, bool async) { int error = 0; TRACE_DEVICE(dev); TRACE_RESUME(0); + dpm_wait(dev->parent, async); down(&dev->sem); if (dev->bus) { @@ -427,7 +515,7 @@ static int device_resume(struct device *dev, pm_message_t state) error = pm_op(dev, dev->bus->pm, state); } else if (dev->bus->resume) { pm_dev_dbg(dev, state, "legacy "); - error = dev->bus->resume(dev); + error = legacy_resume(dev, dev->bus->resume); } if (error) goto End; @@ -448,16 +536,43 @@ static int device_resume(struct device *dev, pm_message_t state) error = pm_op(dev, dev->class->pm, state); } else if (dev->class->resume) { pm_dev_dbg(dev, state, "legacy class "); - error = dev->class->resume(dev); + error = legacy_resume(dev, dev->class->resume); } } End: up(&dev->sem); + 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; + + pm_dev_dbg(dev, pm_transition, "async "); + error = __device_resume(dev, pm_transition, true); + if (error) + pm_dev_err(dev, pm_transition, " async", error); + put_device(dev); +} + +static int device_resume(struct device *dev) +{ + INIT_COMPLETION(dev->power.completion); + + if (pm_async_enabled && dev->power.async_suspend + && !pm_trace_is_enabled()) { + get_device(dev); + async_schedule(async_resume, dev); + return 0; + } + + return __device_resume(dev, pm_transition, false); +} + /** * dpm_resume - Execute "resume" callbacks for non-sysdev devices. * @state: PM transition of the system being carried out. @@ -468,9 +583,11 @@ static int device_resume(struct device *dev, pm_message_t state) static void dpm_resume(pm_message_t state) { struct list_head list; + ktime_t starttime = ktime_get(); INIT_LIST_HEAD(&list); mutex_lock(&dpm_list_mtx); + pm_transition = state; while (!list_empty(&dpm_list)) { struct device *dev = to_device(dpm_list.next); @@ -481,7 +598,7 @@ static void dpm_resume(pm_message_t state) dev->power.status = DPM_RESUMING; mutex_unlock(&dpm_list_mtx); - error = device_resume(dev, state); + error = device_resume(dev); mutex_lock(&dpm_list_mtx); if (error) @@ -496,6 +613,8 @@ static void dpm_resume(pm_message_t state) } list_splice(&list, &dpm_list); mutex_unlock(&dpm_list_mtx); + async_synchronize_full(); + dpm_show_time(starttime, state, NULL); } /** @@ -628,6 +747,7 @@ static int device_suspend_noirq(struct device *dev, pm_message_t state) int dpm_suspend_noirq(pm_message_t state) { struct device *dev; + ktime_t starttime = ktime_get(); int error = 0; suspend_device_irqs(); @@ -643,29 +763,58 @@ int dpm_suspend_noirq(pm_message_t state) mutex_unlock(&dpm_list_mtx); if (error) dpm_resume_noirq(resume_event(state)); + else + dpm_show_time(starttime, state, "late"); return error; } EXPORT_SYMBOL_GPL(dpm_suspend_noirq); /** + * legacy_suspend - Execute a legacy (bus or class) suspend callback for device. + * dev: Device to suspend. + * cb: Suspend callback to execute. + */ +static int legacy_suspend(struct device *dev, pm_message_t state, + int (*cb)(struct device *dev, pm_message_t state)) +{ + int error; + ktime_t calltime; + + calltime = initcall_debug_start(dev); + + error = cb(dev, state); + suspend_report_result(cb, error); + + initcall_debug_report(dev, calltime, error); + + return error; +} + +static int async_error; + +/** * 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) +static int __device_suspend(struct device *dev, pm_message_t state, bool async) { int error = 0; + dpm_wait_for_children(dev, async); down(&dev->sem); + if (async_error) + goto End; + if (dev->class) { if (dev->class->pm) { pm_dev_dbg(dev, state, "class "); error = pm_op(dev, dev->class->pm, state); } else if (dev->class->suspend) { pm_dev_dbg(dev, state, "legacy class "); - error = dev->class->suspend(dev, state); - suspend_report_result(dev->class->suspend, error); + error = legacy_suspend(dev, state, dev->class->suspend); } if (error) goto End; @@ -686,16 +835,48 @@ static int device_suspend(struct device *dev, pm_message_t state) error = pm_op(dev, dev->bus->pm, state); } else if (dev->bus->suspend) { pm_dev_dbg(dev, state, "legacy "); - error = dev->bus->suspend(dev, state); - suspend_report_result(dev->bus->suspend, error); + error = legacy_suspend(dev, state, dev->bus->suspend); } } + + if (!error) + dev->power.status = DPM_OFF; + End: up(&dev->sem); + complete_all(&dev->power.completion); return error; } +static void async_suspend(void *data, async_cookie_t cookie) +{ + struct device *dev = (struct device *)data; + int error; + + pm_dev_dbg(dev, pm_transition, "async "); + error = __device_suspend(dev, pm_transition, true); + if (error) { + pm_dev_err(dev, pm_transition, " async", error); + async_error = error; + } + + put_device(dev); +} + +static int device_suspend(struct device *dev) +{ + INIT_COMPLETION(dev->power.completion); + + if (pm_async_enabled && dev->power.async_suspend) { + get_device(dev); + async_schedule(async_suspend, dev); + 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. @@ -703,17 +884,20 @@ static int device_suspend(struct device *dev, pm_message_t state) static int dpm_suspend(pm_message_t state) { struct list_head list; + ktime_t starttime = ktime_get(); int error = 0; INIT_LIST_HEAD(&list); mutex_lock(&dpm_list_mtx); + pm_transition = state; + async_error = 0; while (!list_empty(&dpm_list)) { struct device *dev = to_device(dpm_list.prev); get_device(dev); mutex_unlock(&dpm_list_mtx); - error = device_suspend(dev, state); + error = device_suspend(dev); mutex_lock(&dpm_list_mtx); if (error) { @@ -721,13 +905,19 @@ static int dpm_suspend(pm_message_t state) put_device(dev); break; } - dev->power.status = DPM_OFF; if (!list_empty(&dev->power.entry)) list_move(&dev->power.entry, &list); put_device(dev); + if (async_error) + break; } list_splice(&list, dpm_list.prev); mutex_unlock(&dpm_list_mtx); + async_synchronize_full(); + if (!error) + error = async_error; + if (!error) + dpm_show_time(starttime, state, NULL); return error; } diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h index b8fa1aa5225a..c0bd03c83b9c 100644 --- a/drivers/base/power/power.h +++ b/drivers/base/power/power.h @@ -12,10 +12,10 @@ static inline void pm_runtime_remove(struct device *dev) {} #ifdef CONFIG_PM_SLEEP -/* - * main.c - */ +/* kernel/power/main.c */ +extern int pm_async_enabled; +/* drivers/base/power/main.c */ extern struct list_head dpm_list; /* The active device list */ static inline struct device *to_device(struct list_head *entry) diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c index 596aeecfdffe..0f75ebb83a79 100644 --- a/drivers/base/power/sysfs.c +++ b/drivers/base/power/sysfs.c @@ -38,6 +38,22 @@ * wakeup events internally (unless they are disabled), keeping * their hardware in low power modes whenever they're unused. This * saves runtime power, without requiring system-wide sleep states. + * + * async - Report/change current async suspend setting for the device + * + * If set, the PM core will attempt to suspend and resume the device during + * system power transitions (e.g. suspend to RAM, hibernation) in parallel + * with other devices it doesn't appear to depend on (to the PM core's + * knowledge). + * + * + "enabled\n" to permit the asynchronous suspend/resume of the device + * + "disabled\n" to forbid it + * + * NOTE: It generally is unsafe to permit the asynchronous suspend/resume + * of a device unless it is certain that all of the PM dependencies of the + * device are known to the PM core. However, for some devices this + * attribute is set to "enabled" by bus type code or device drivers and in + * that cases it should be safe to leave the default value. */ static const char enabled[] = "enabled"; @@ -77,9 +93,40 @@ wake_store(struct device * dev, struct device_attribute *attr, static DEVICE_ATTR(wakeup, 0644, wake_show, wake_store); +#ifdef CONFIG_PM_SLEEP_ADVANCED_DEBUG +static ssize_t async_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%s\n", + device_async_suspend_enabled(dev) ? enabled : disabled); +} + +static ssize_t async_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t n) +{ + char *cp; + int len = n; + + cp = memchr(buf, '\n', n); + if (cp) + len = cp - buf; + if (len == sizeof enabled - 1 && strncmp(buf, enabled, len) == 0) + device_enable_async_suspend(dev, true); + else if (len == sizeof disabled - 1 && strncmp(buf, disabled, len) == 0) + device_enable_async_suspend(dev, false); + else + return -EINVAL; + return n; +} + +static DEVICE_ATTR(async, 0644, async_show, async_store); +#endif /* CONFIG_PM_SLEEP_ADVANCED_DEBUG */ static struct attribute * power_attrs[] = { &dev_attr_wakeup.attr, +#ifdef CONFIG_PM_SLEEP_ADVANCED_DEBUG + &dev_attr_async.attr, +#endif NULL, }; static struct attribute_group pm_attr_group = { |