diff options
Diffstat (limited to 'drivers/base')
| -rw-r--r-- | drivers/base/power/Makefile | 1 | ||||
| -rw-r--r-- | drivers/base/power/generic_ops.c | 233 | ||||
| -rw-r--r-- | drivers/base/power/main.c | 143 | ||||
| -rw-r--r-- | drivers/base/power/power.h | 6 | ||||
| -rw-r--r-- | drivers/base/power/runtime.c | 45 | ||||
| -rw-r--r-- | drivers/base/power/sysfs.c | 100 |
6 files changed, 514 insertions, 14 deletions
diff --git a/drivers/base/power/Makefile b/drivers/base/power/Makefile index 3ce3519e8f30..89de75325cea 100644 --- a/drivers/base/power/Makefile +++ b/drivers/base/power/Makefile @@ -1,6 +1,7 @@ obj-$(CONFIG_PM) += sysfs.o obj-$(CONFIG_PM_SLEEP) += main.o obj-$(CONFIG_PM_RUNTIME) += runtime.o +obj-$(CONFIG_PM_OPS) += generic_ops.o obj-$(CONFIG_PM_TRACE_RTC) += trace.o ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG diff --git a/drivers/base/power/generic_ops.c b/drivers/base/power/generic_ops.c new file mode 100644 index 000000000000..4b29d4981253 --- /dev/null +++ b/drivers/base/power/generic_ops.c @@ -0,0 +1,233 @@ +/* + * drivers/base/power/generic_ops.c - Generic PM callbacks for subsystems + * + * Copyright (c) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + * + * This file is released under the GPLv2. + */ + +#include <linux/pm.h> +#include <linux/pm_runtime.h> + +#ifdef CONFIG_PM_RUNTIME +/** + * pm_generic_runtime_idle - Generic runtime idle callback for subsystems. + * @dev: Device to handle. + * + * If PM operations are defined for the @dev's driver and they include + * ->runtime_idle(), execute it and return its error code, if nonzero. + * Otherwise, execute pm_runtime_suspend() for the device and return 0. + */ +int pm_generic_runtime_idle(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + if (pm && pm->runtime_idle) { + int ret = pm->runtime_idle(dev); + if (ret) + return ret; + } + + pm_runtime_suspend(dev); + return 0; +} +EXPORT_SYMBOL_GPL(pm_generic_runtime_idle); + +/** + * pm_generic_runtime_suspend - Generic runtime suspend callback for subsystems. + * @dev: Device to suspend. + * + * If PM operations are defined for the @dev's driver and they include + * ->runtime_suspend(), execute it and return its error code. Otherwise, + * return -EINVAL. + */ +int pm_generic_runtime_suspend(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int ret; + + ret = pm && pm->runtime_suspend ? pm->runtime_suspend(dev) : -EINVAL; + + return ret; +} +EXPORT_SYMBOL_GPL(pm_generic_runtime_suspend); + +/** + * pm_generic_runtime_resume - Generic runtime resume callback for subsystems. + * @dev: Device to resume. + * + * If PM operations are defined for the @dev's driver and they include + * ->runtime_resume(), execute it and return its error code. Otherwise, + * return -EINVAL. + */ +int pm_generic_runtime_resume(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int ret; + + ret = pm && pm->runtime_resume ? pm->runtime_resume(dev) : -EINVAL; + + return ret; +} +EXPORT_SYMBOL_GPL(pm_generic_runtime_resume); +#endif /* CONFIG_PM_RUNTIME */ + +#ifdef CONFIG_PM_SLEEP +/** + * __pm_generic_call - Generic suspend/freeze/poweroff/thaw subsystem callback. + * @dev: Device to handle. + * @event: PM transition of the system under way. + * + * If the device has not been suspended at run time, execute the + * suspend/freeze/poweroff/thaw callback provided by its driver, if defined, and + * return its error code. Otherwise, return zero. + */ +static int __pm_generic_call(struct device *dev, int event) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int (*callback)(struct device *); + + if (!pm || pm_runtime_suspended(dev)) + return 0; + + switch (event) { + case PM_EVENT_SUSPEND: + callback = pm->suspend; + break; + case PM_EVENT_FREEZE: + callback = pm->freeze; + break; + case PM_EVENT_HIBERNATE: + callback = pm->poweroff; + break; + case PM_EVENT_THAW: + callback = pm->thaw; + break; + default: + callback = NULL; + break; + } + + return callback ? callback(dev) : 0; +} + +/** + * pm_generic_suspend - Generic suspend callback for subsystems. + * @dev: Device to suspend. + */ +int pm_generic_suspend(struct device *dev) +{ + return __pm_generic_call(dev, PM_EVENT_SUSPEND); +} +EXPORT_SYMBOL_GPL(pm_generic_suspend); + +/** + * pm_generic_freeze - Generic freeze callback for subsystems. + * @dev: Device to freeze. + */ +int pm_generic_freeze(struct device *dev) +{ + return __pm_generic_call(dev, PM_EVENT_FREEZE); +} +EXPORT_SYMBOL_GPL(pm_generic_freeze); + +/** + * pm_generic_poweroff - Generic poweroff callback for subsystems. + * @dev: Device to handle. + */ +int pm_generic_poweroff(struct device *dev) +{ + return __pm_generic_call(dev, PM_EVENT_HIBERNATE); +} +EXPORT_SYMBOL_GPL(pm_generic_poweroff); + +/** + * pm_generic_thaw - Generic thaw callback for subsystems. + * @dev: Device to thaw. + */ +int pm_generic_thaw(struct device *dev) +{ + return __pm_generic_call(dev, PM_EVENT_THAW); +} +EXPORT_SYMBOL_GPL(pm_generic_thaw); + +/** + * __pm_generic_resume - Generic resume/restore callback for subsystems. + * @dev: Device to handle. + * @event: PM transition of the system under way. + * + * Execute the resume/resotre callback provided by the @dev's driver, if + * defined. If it returns 0, change the device's runtime PM status to 'active'. + * Return the callback's error code. + */ +static int __pm_generic_resume(struct device *dev, int event) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int (*callback)(struct device *); + int ret; + + if (!pm) + return 0; + + switch (event) { + case PM_EVENT_RESUME: + callback = pm->resume; + break; + case PM_EVENT_RESTORE: + callback = pm->restore; + break; + default: + callback = NULL; + break; + } + + if (!callback) + return 0; + + ret = callback(dev); + if (!ret) { + pm_runtime_disable(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); + } + + return ret; +} + +/** + * pm_generic_resume - Generic resume callback for subsystems. + * @dev: Device to resume. + */ +int pm_generic_resume(struct device *dev) +{ + return __pm_generic_resume(dev, PM_EVENT_RESUME); +} +EXPORT_SYMBOL_GPL(pm_generic_resume); + +/** + * pm_generic_restore - Generic restore callback for subsystems. + * @dev: Device to restore. + */ +int pm_generic_restore(struct device *dev) +{ + return __pm_generic_resume(dev, PM_EVENT_RESTORE); +} +EXPORT_SYMBOL_GPL(pm_generic_restore); +#endif /* CONFIG_PM_SLEEP */ + +struct dev_pm_ops generic_subsys_pm_ops = { +#ifdef CONFIG_PM_SLEEP + .suspend = pm_generic_suspend, + .resume = pm_generic_resume, + .freeze = pm_generic_freeze, + .thaw = pm_generic_thaw, + .poweroff = pm_generic_poweroff, + .restore = pm_generic_restore, +#endif +#ifdef CONFIG_PM_RUNTIME + .runtime_suspend = pm_generic_runtime_suspend, + .runtime_resume = pm_generic_runtime_resume, + .runtime_idle = pm_generic_runtime_idle, +#endif +}; +EXPORT_SYMBOL_GPL(generic_subsys_pm_ops); diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index a5142bddef41..0e26a6f6fd48 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); @@ -188,6 +192,31 @@ static void initcall_debug_report(struct device *dev, ktime_t 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); +} + +/** * pm_op - Execute the PM operation appropriate for given PM event. * @dev: Device to handle. * @ops: PM operations to choose from. @@ -271,8 +300,9 @@ static int pm_noirq_op(struct device *dev, ktime_t calltime, delta, rettime; if (initcall_debug) { - pr_info("calling %s_i+ @ %i\n", - dev_name(dev), task_pid_nr(current)); + pr_info("calling %s+ @ %i, parent: %s\n", + dev_name(dev), task_pid_nr(current), + dev->parent ? dev_name(dev->parent) : "none"); calltime = ktime_get(); } @@ -468,16 +498,20 @@ static int legacy_resume(struct device *dev, int (*cb)(struct device *dev)) * 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); + dev->power.status = DPM_RESUMING; + if (dev->bus) { if (dev->bus->pm) { pm_dev_dbg(dev, state, ""); @@ -510,11 +544,29 @@ static int device_resume(struct device *dev, pm_message_t state) } 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; + + error = device_resume(dev, pm_transition, true); + if (error) + pm_dev_err(dev, pm_transition, " async", error); + put_device(dev); +} + +static bool is_async(struct device *dev) +{ + return dev->power.async_suspend && pm_async_enabled + && !pm_trace_is_enabled(); +} + /** * dpm_resume - Execute "resume" callbacks for non-sysdev devices. * @state: PM transition of the system being carried out. @@ -525,21 +577,33 @@ static int device_resume(struct device *dev, pm_message_t state) static void dpm_resume(pm_message_t state) { struct list_head list; + struct device *dev; ktime_t starttime = ktime_get(); INIT_LIST_HEAD(&list); mutex_lock(&dpm_list_mtx); - while (!list_empty(&dpm_list)) { - struct device *dev = to_device(dpm_list.next); + pm_transition = state; + + list_for_each_entry(dev, &dpm_list, power.entry) { + if (dev->power.status < DPM_OFF) + continue; + + INIT_COMPLETION(dev->power.completion); + if (is_async(dev)) { + get_device(dev); + async_schedule(async_resume, dev); + } + } + while (!list_empty(&dpm_list)) { + dev = to_device(dpm_list.next); get_device(dev); - if (dev->power.status >= DPM_OFF) { + if (dev->power.status >= DPM_OFF && !is_async(dev)) { int error; - dev->power.status = DPM_RESUMING; mutex_unlock(&dpm_list_mtx); - error = device_resume(dev, state); + error = device_resume(dev, state, false); mutex_lock(&dpm_list_mtx); if (error) @@ -554,6 +618,7 @@ 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); } @@ -731,17 +796,24 @@ static int legacy_suspend(struct device *dev, pm_message_t state, 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 "); @@ -772,12 +844,44 @@ static int device_suspend(struct device *dev, pm_message_t state) 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; + + 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. @@ -790,13 +894,15 @@ static int dpm_suspend(pm_message_t state) 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) { @@ -804,13 +910,17 @@ 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; @@ -936,3 +1046,14 @@ void __suspend_report_result(const char *function, void *fn, int ret) printk(KERN_ERR "%s(): %pF 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. + * @dev: Device to wait for. + * @subordinate: Device that needs to wait for @dev. + */ +void device_pm_wait_for_dev(struct device *subordinate, struct device *dev) +{ + dpm_wait(dev, subordinate->power.async_suspend); +} +EXPORT_SYMBOL_GPL(device_pm_wait_for_dev); 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/runtime.c b/drivers/base/power/runtime.c index f8b044e8aef7..626dd147b75f 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -1011,6 +1011,50 @@ void pm_runtime_enable(struct device *dev) EXPORT_SYMBOL_GPL(pm_runtime_enable); /** + * pm_runtime_forbid - Block run-time PM of a device. + * @dev: Device to handle. + * + * Increase the device's usage count and clear its power.runtime_auto flag, + * so that it cannot be suspended at run time until pm_runtime_allow() is called + * for it. + */ +void pm_runtime_forbid(struct device *dev) +{ + spin_lock_irq(&dev->power.lock); + if (!dev->power.runtime_auto) + goto out; + + dev->power.runtime_auto = false; + atomic_inc(&dev->power.usage_count); + __pm_runtime_resume(dev, false); + + out: + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(pm_runtime_forbid); + +/** + * pm_runtime_allow - Unblock run-time PM of a device. + * @dev: Device to handle. + * + * Decrease the device's usage count and set its power.runtime_auto flag. + */ +void pm_runtime_allow(struct device *dev) +{ + spin_lock_irq(&dev->power.lock); + if (dev->power.runtime_auto) + goto out; + + dev->power.runtime_auto = true; + if (atomic_dec_and_test(&dev->power.usage_count)) + __pm_runtime_idle(dev); + + out: + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(pm_runtime_allow); + +/** * pm_runtime_init - Initialize run-time PM fields in given device object. * @dev: Device object to initialize. */ @@ -1028,6 +1072,7 @@ void pm_runtime_init(struct device *dev) atomic_set(&dev->power.child_count, 0); pm_suspend_ignore_children(dev, false); + dev->power.runtime_auto = true; dev->power.request_pending = false; dev->power.request = RPM_REQ_NONE; diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c index 596aeecfdffe..86fd9373447e 100644 --- a/drivers/base/power/sysfs.c +++ b/drivers/base/power/sysfs.c @@ -4,9 +4,25 @@ #include <linux/device.h> #include <linux/string.h> +#include <linux/pm_runtime.h> #include "power.h" /* + * control - Report/change current runtime PM setting of the device + * + * Runtime power management of a device can be blocked with the help of + * this attribute. All devices have one of the following two values for + * the power/control file: + * + * + "auto\n" to allow the device to be power managed at run time; + * + "on\n" to prevent the device from being power managed at run time; + * + * The default for all devices is "auto", which means that devices may be + * subject to automatic power management, depending on their drivers. + * Changing this attribute to "on" prevents the driver from power managing + * the device at run time. Doing that while the device is suspended causes + * it to be woken up. + * * wakeup - Report/change current wakeup option for device * * Some devices support "wakeup" events, which are hardware signals @@ -38,11 +54,61 @@ * 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 + * + * Asynchronous suspend and resume of the device during system-wide power + * state transitions can be enabled by writing "enabled" to this file. + * Analogously, if "disabled" is written to this file, the device will be + * suspended and resumed synchronously. + * + * All devices have one of the following two values for power/async: + * + * + "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"; static const char disabled[] = "disabled"; +#ifdef CONFIG_PM_RUNTIME +static const char ctrl_auto[] = "auto"; +static const char ctrl_on[] = "on"; + +static ssize_t control_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%s\n", + dev->power.runtime_auto ? ctrl_auto : ctrl_on); +} + +static ssize_t control_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 ctrl_auto - 1 && strncmp(buf, ctrl_auto, len) == 0) + pm_runtime_allow(dev); + else if (len == sizeof ctrl_on - 1 && strncmp(buf, ctrl_on, len) == 0) + pm_runtime_forbid(dev); + else + return -EINVAL; + return n; +} + +static DEVICE_ATTR(control, 0644, control_show, control_store); +#endif + static ssize_t wake_show(struct device * dev, struct device_attribute *attr, char * buf) { @@ -77,9 +143,43 @@ 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); + else if (len == sizeof disabled - 1 && strncmp(buf, disabled, len) == 0) + device_disable_async_suspend(dev); + 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[] = { +#ifdef CONFIG_PM_RUNTIME + &dev_attr_control.attr, +#endif &dev_attr_wakeup.attr, +#ifdef CONFIG_PM_SLEEP_ADVANCED_DEBUG + &dev_attr_async.attr, +#endif NULL, }; static struct attribute_group pm_attr_group = { |