diff options
| -rw-r--r-- | drivers/base/power/runtime.c | 375 |
1 files changed, 140 insertions, 235 deletions
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 0c1db879544..d7b5d84c235 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -2,6 +2,7 @@ * drivers/base/power/runtime.c - Helper functions for device run-time PM * * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + * Copyright (C) 2010 Alan Stern <stern@rowland.harvard.edu> * * This file is released under the GPLv2. */ @@ -11,8 +12,6 @@ #include <linux/jiffies.h> static int __pm_runtime_resume(struct device *dev, int rpmflags); -static int __pm_request_idle(struct device *dev); -static int __pm_request_resume(struct device *dev); /** * update_pm_runtime_accounting - Update the time accounting of power states @@ -79,40 +78,84 @@ static void pm_runtime_cancel_pending(struct device *dev) } /** - * __pm_runtime_idle - Notify device bus type if the device can be suspended. - * @dev: Device to notify the bus type about. - * - * This function must be called under dev->power.lock with interrupts disabled. + * rpm_check_suspend_allowed - Test whether a device may be suspended. + * @dev: Device to test. */ -static int __pm_runtime_idle(struct device *dev) - __releases(&dev->power.lock) __acquires(&dev->power.lock) +static int rpm_check_suspend_allowed(struct device *dev) { int retval = 0; if (dev->power.runtime_error) retval = -EINVAL; - else if (dev->power.idle_notification) - retval = -EINPROGRESS; else if (atomic_read(&dev->power.usage_count) > 0 - || dev->power.disable_depth > 0 - || dev->power.runtime_status != RPM_ACTIVE) + || dev->power.disable_depth > 0) retval = -EAGAIN; else if (!pm_children_suspended(dev)) retval = -EBUSY; + + /* Pending resume requests take precedence over suspends. */ + else if ((dev->power.deferred_resume + && dev->power.status == RPM_SUSPENDING) + || (dev->power.request_pending + && dev->power.request == RPM_REQ_RESUME)) + retval = -EAGAIN; + else if (dev->power.runtime_status == RPM_SUSPENDED) + retval = 1; + + return retval; +} + + +/** + * __pm_runtime_idle - Notify device bus type if the device can be suspended. + * @dev: Device to notify the bus type about. + * @rpmflags: Flag bits. + * + * Check if the device's run-time PM status allows it to be suspended. If + * another idle notification has been started earlier, return immediately. If + * the RPM_ASYNC flag is set then queue an idle-notification request; otherwise + * run the ->runtime_idle() callback directly. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static int __pm_runtime_idle(struct device *dev, int rpmflags) + __releases(&dev->power.lock) __acquires(&dev->power.lock) +{ + int retval; + + retval = rpm_check_suspend_allowed(dev); + if (retval < 0) + ; /* Conditions are wrong. */ + + /* Idle notifications are allowed only in the RPM_ACTIVE state. */ + else if (dev->power.runtime_status != RPM_ACTIVE) + retval = -EAGAIN; + + /* + * Any pending request other than an idle notification takes + * precedence over us, except that the timer may be running. + */ + else if (dev->power.request_pending && + dev->power.request > RPM_REQ_IDLE) + retval = -EAGAIN; + + /* Act as though RPM_NOWAIT is always set. */ + else if (dev->power.idle_notification) + retval = -EINPROGRESS; if (retval) goto out; - if (dev->power.request_pending) { - /* - * If an idle notification request is pending, cancel it. Any - * other pending request takes precedence over us. - */ - if (dev->power.request == RPM_REQ_IDLE) { - dev->power.request = RPM_REQ_NONE; - } else if (dev->power.request != RPM_REQ_NONE) { - retval = -EAGAIN; - goto out; + /* Pending requests need to be canceled. */ + dev->power.request = RPM_REQ_NONE; + + /* Carry out an asynchronous or a synchronous idle notification. */ + if (rpmflags & RPM_ASYNC) { + dev->power.request = RPM_REQ_IDLE; + if (!dev->power.request_pending) { + dev->power.request_pending = true; + queue_work(pm_wq, &dev->power.work); } + goto out; } dev->power.idle_notification = true; @@ -154,7 +197,7 @@ int pm_runtime_idle(struct device *dev) int retval; spin_lock_irq(&dev->power.lock); - retval = __pm_runtime_idle(dev); + retval = __pm_runtime_idle(dev, 0); spin_unlock_irq(&dev->power.lock); return retval; @@ -166,11 +209,14 @@ EXPORT_SYMBOL_GPL(pm_runtime_idle); * @dev: Device to suspend. * @rpmflags: Flag bits. * - * Check if the device can be suspended and run the ->runtime_suspend() callback - * provided by its bus type. If another suspend has been started earlier, - * either return immediately or wait for it to finish, depending on the - * RPM_NOWAIT flag. If an idle notification or suspend request is pending or - * scheduled, cancel it. + * Check if the device's run-time PM status allows it to be suspended. If + * another suspend has been started earlier, either return immediately or wait + * for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC flags. Cancel a + * pending idle notification. If the RPM_ASYNC flag is set then queue a + * suspend request; otherwise run the ->runtime_suspend() callback directly. + * If a deferred resume was requested while the callback was running then carry + * it out; otherwise send an idle notification for the device (if the suspend + * failed) or for its parent (if the suspend succeeded). * * This function must be called under dev->power.lock with interrupts disabled. */ @@ -179,41 +225,30 @@ static int __pm_runtime_suspend(struct device *dev, int rpmflags) { struct device *parent = NULL; bool notify = false; - int retval = 0; + int retval; dev_dbg(dev, "%s flags 0x%x\n", __func__, rpmflags); repeat: - if (dev->power.runtime_error) { - retval = -EINVAL; - goto out; - } + retval = rpm_check_suspend_allowed(dev); - /* Pending resume requests take precedence over us. */ - if (dev->power.request_pending - && dev->power.request == RPM_REQ_RESUME) { + if (retval < 0) + ; /* Conditions are wrong. */ + + /* Synchronous suspends are not allowed in the RPM_RESUMING state. */ + else if (dev->power.runtime_status == RPM_RESUMING && + !(rpmflags & RPM_ASYNC)) retval = -EAGAIN; + if (retval) goto out; - } /* Other scheduled or pending requests need to be canceled. */ pm_runtime_cancel_pending(dev); - if (dev->power.runtime_status == RPM_SUSPENDED) - retval = 1; - else if (dev->power.runtime_status == RPM_RESUMING - || dev->power.disable_depth > 0 - || atomic_read(&dev->power.usage_count) > 0) - retval = -EAGAIN; - else if (!pm_children_suspended(dev)) - retval = -EBUSY; - if (retval) - goto out; - if (dev->power.runtime_status == RPM_SUSPENDING) { DEFINE_WAIT(wait); - if (rpmflags & RPM_NOWAIT) { + if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { retval = -EINPROGRESS; goto out; } @@ -235,6 +270,16 @@ static int __pm_runtime_suspend(struct device *dev, int rpmflags) goto repeat; } + /* Carry out an asynchronous or a synchronous suspend. */ + if (rpmflags & RPM_ASYNC) { + dev->power.request = RPM_REQ_SUSPEND; + if (!dev->power.request_pending) { + dev->power.request_pending = true; + queue_work(pm_wq, &dev->power.work); + } + goto out; + } + __update_runtime_status(dev, RPM_SUSPENDING); dev->power.deferred_resume = false; @@ -267,6 +312,7 @@ static int __pm_runtime_suspend(struct device *dev, int rpmflags) if (retval) { __update_runtime_status(dev, RPM_ACTIVE); + dev->power.deferred_resume = 0; if (retval == -EAGAIN || retval == -EBUSY) { if (dev->power.timer_expires == 0) notify = true; @@ -292,7 +338,7 @@ static int __pm_runtime_suspend(struct device *dev, int rpmflags) } if (notify) - __pm_runtime_idle(dev); + __pm_runtime_idle(dev, 0); if (parent && !parent->power.ignore_children) { spin_unlock_irq(&dev->power.lock); @@ -329,13 +375,15 @@ EXPORT_SYMBOL_GPL(pm_runtime_suspend); * @dev: Device to resume. * @rpmflags: Flag bits. * - * Check if the device can be woken up and run the ->runtime_resume() callback - * provided by its bus type. If another resume has been started earlier, - * either return imediately or wait for it to finish, depending on the - * RPM_NOWAIT flag. If there's a suspend running in parallel with this - * function, either tell the other process to resume after suspending - * (deferred_resume) or wait for it to finish, depending on the RPM_NOWAIT - * flag. Cancel any scheduled or pending requests. + * Check if the device's run-time PM status allows it to be resumed. Cancel + * any scheduled or pending requests. If another resume has been started + * earlier, either return imediately or wait for it to finish, depending on the + * RPM_NOWAIT and RPM_ASYNC flags. Similarly, if there's a suspend running in + * parallel with this function, either tell the other process to resume after + * suspending (deferred_resume) or wait for it to finish. If the RPM_ASYNC + * flag is set then queue a resume request; otherwise run the + * ->runtime_resume() callback directly. Queue an idle notification for the + * device if the resume succeeded. * * This function must be called under dev->power.lock with interrupts disabled. */ @@ -348,28 +396,30 @@ static int __pm_runtime_resume(struct device *dev, int rpmflags) dev_dbg(dev, "%s flags 0x%x\n", __func__, rpmflags); repeat: - if (dev->power.runtime_error) { + if (dev->power.runtime_error) retval = -EINVAL; + else if (dev->power.disable_depth > 0) + retval = -EAGAIN; + if (retval) goto out; - } + /* Other scheduled or pending requests need to be canceled. */ pm_runtime_cancel_pending(dev); - if (dev->power.runtime_status == RPM_ACTIVE) + if (dev->power.runtime_status == RPM_ACTIVE) { retval = 1; - else if (dev->power.disable_depth > 0) - retval = -EAGAIN; - if (retval) goto out; + } if (dev->power.runtime_status == RPM_RESUMING || dev->power.runtime_status == RPM_SUSPENDING) { DEFINE_WAIT(wait); - if (rpmflags & RPM_NOWAIT) { + if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { if (dev->power.runtime_status == RPM_SUSPENDING) dev->power.deferred_resume = true; - retval = -EINPROGRESS; + else + retval = -EINPROGRESS; goto out; } @@ -391,6 +441,17 @@ static int __pm_runtime_resume(struct device *dev, int rpmflags) goto repeat; } + /* Carry out an asynchronous or a synchronous resume. */ + if (rpmflags & RPM_ASYNC) { + dev->power.request = RPM_REQ_RESUME; + if (!dev->power.request_pending) { + dev->power.request_pending = true; + queue_work(pm_wq, &dev->power.work); + } + retval = 0; + goto out; + } + if (!parent && dev->parent) { /* * Increment the parent's resume counter and resume it if @@ -460,7 +521,7 @@ static int __pm_runtime_resume(struct device *dev, int rpmflags) wake_up_all(&dev->power.wait_queue); if (!retval) - __pm_request_idle(dev); + __pm_runtime_idle(dev, RPM_ASYNC); out: if (parent) { @@ -517,7 +578,7 @@ static void pm_runtime_work(struct work_struct *work) case RPM_REQ_NONE: break; case RPM_REQ_IDLE: - __pm_runtime_idle(dev); + __pm_runtime_idle(dev, RPM_NOWAIT); break; case RPM_REQ_SUSPEND: __pm_runtime_suspend(dev, RPM_NOWAIT); @@ -532,47 +593,6 @@ static void pm_runtime_work(struct work_struct *work) } /** - * __pm_request_idle - Submit an idle notification request for given device. - * @dev: Device to handle. - * - * Check if the device's run-time PM status is correct for suspending the device - * and queue up a request to run __pm_runtime_idle() for it. - * - * This function must be called under dev->power.lock with interrupts disabled. - */ -static int __pm_request_idle(struct device *dev) -{ - int retval = 0; - - if (dev->power.runtime_error) - retval = -EINVAL; - else if (atomic_read(&dev->power.usage_count) > 0 - || dev->power.disable_depth > 0 - || dev->power.runtime_status == RPM_SUSPENDED - || dev->power.runtime_status == RPM_SUSPENDING) - retval = -EAGAIN; - else if (!pm_children_suspended(dev)) - retval = -EBUSY; - if (retval) - return retval; - - if (dev->power.request_pending) { - /* Any requests other then RPM_REQ_IDLE take precedence. */ - if (dev->power.request == RPM_REQ_NONE) - dev->power.request = RPM_REQ_IDLE; - else if (dev->power.request != RPM_REQ_IDLE) - retval = -EAGAIN; - return retval; - } - - dev->power.request = RPM_REQ_IDLE; - dev->power.request_pending = true; - queue_work(pm_wq, &dev->power.work); - - return retval; -} - -/** * pm_request_idle - Submit an idle notification request for given device. * @dev: Device to handle. */ @@ -582,7 +602,7 @@ int pm_request_idle(struct device *dev) int retval; spin_lock_irqsave(&dev->power.lock, flags); - retval = __pm_request_idle(dev); + retval = __pm_runtime_idle(dev, RPM_ASYNC); spin_unlock_irqrestore(&dev->power.lock, flags); return retval; @@ -590,59 +610,10 @@ int pm_request_idle(struct device *dev) EXPORT_SYMBOL_GPL(pm_request_idle); /** - * __pm_request_suspend - Submit a suspend request for given device. - * @dev: Device to suspend. - * - * This function must be called under dev->power.lock with interrupts disabled. - */ -static int __pm_request_suspend(struct device *dev) -{ - int retval = 0; - - if (dev->power.runtime_error) - return -EINVAL; - - if (dev->power.runtime_status == RPM_SUSPENDED) - retval = 1; - else if (atomic_read(&dev->power.usage_count) > 0 - || dev->power.disable_depth > 0) - retval = -EAGAIN; - else if (dev->power.runtime_status == RPM_SUSPENDING) - retval = -EINPROGRESS; - else if (!pm_children_suspended(dev)) - retval = -EBUSY; - if (retval < 0) - return retval; - - pm_runtime_deactivate_timer(dev); - - if (dev->power.request_pending) { - /* - * Pending resume requests take precedence over us, but we can - * overtake any other pending request. - */ - if (dev->power.request == RPM_REQ_RESUME) - retval = -EAGAIN; - else if (dev->power.request != RPM_REQ_SUSPEND) - dev->power.request = retval ? - RPM_REQ_NONE : RPM_REQ_SUSPEND; - return retval; - } else if (retval) { - return retval; - } - - dev->power.request = RPM_REQ_SUSPEND; - dev->power.request_pending = true; - queue_work(pm_wq, &dev->power.work); - - return 0; -} - -/** * pm_suspend_timer_fn - Timer function for pm_schedule_suspend(). * @data: Device pointer passed by pm_schedule_suspend(). * - * Check if the time is right and execute __pm_request_suspend() in that case. + * Check if the time is right and queue a suspend request. */ static void pm_suspend_timer_fn(unsigned long data) { @@ -656,7 +627,7 @@ static void pm_suspend_timer_fn(unsigned long data) /* If 'expire' is after 'jiffies' we've been called too early. */ if (expires > 0 && !time_after(expires, jiffies)) { dev->power.timer_expires = 0; - __pm_request_suspend(dev); + __pm_runtime_suspend(dev, RPM_ASYNC); } spin_unlock_irqrestore(&dev->power.lock, flags); @@ -670,47 +641,24 @@ static void pm_suspend_timer_fn(unsigned long data) int pm_schedule_suspend(struct device *dev, unsigned int delay) { unsigned long flags; - int retval = 0; + int retval; spin_lock_irqsave(&dev->power.lock, flags); - if (dev->power.runtime_error) { - retval = -EINVAL; - goto out; - } - if (!delay) { - retval = __pm_request_suspend(dev); + retval = __pm_runtime_suspend(dev, RPM_ASYNC); goto out; } - pm_runtime_deactivate_timer(dev); - - if (dev->power.request_pending) { - /* - * Pending resume requests take precedence over us, but any - * other pending requests have to be canceled. - */ - if (dev->power.request == RPM_REQ_RESUME) { - retval = -EAGAIN; - goto out; - } - dev->power.request = RPM_REQ_NONE; - } - - if (dev->power.runtime_status == RPM_SUSPENDED) - retval = 1; - else if (atomic_read(&dev->power.usage_count) > 0 - || dev->power.disable_depth > 0) - retval = -EAGAIN; - else if (!pm_children_suspended(dev)) - retval = -EBUSY; + retval = rpm_check_suspend_allowed(dev); if (retval) goto out; + /* Other scheduled or pending requests need to be canceled. */ + pm_runtime_cancel_pending(dev); + dev->power.timer_expires = jiffies + msecs_to_jiffies(delay); - if (!dev->power.timer_expires) - dev->power.timer_expires = 1; + dev->power.timer_expires += !dev->power.timer_expires; mod_timer(&dev->power.suspend_timer, dev->power.timer_expires); out: @@ -723,49 +671,6 @@ EXPORT_SYMBOL_GPL(pm_schedule_suspend); /** * pm_request_resume - Submit a resume request for given device. * @dev: Device to resume. - * - * This function must be called under dev->power.lock with interrupts disabled. - */ -static int __pm_request_resume(struct device *dev) -{ - int retval = 0; - - if (dev->power.runtime_error) - return -EINVAL; - - if (dev->power.runtime_status == RPM_ACTIVE) - retval = 1; - else if (dev->power.runtime_status == RPM_RESUMING) - retval = -EINPROGRESS; - else if (dev->power.disable_depth > 0) - retval = -EAGAIN; - if (retval < 0) - return retval; - - pm_runtime_deactivate_timer(dev); - - if (dev->power.runtime_status == RPM_SUSPENDING) { - dev->power.deferred_resume = true; - return retval; - } - if (dev->power.request_pending) { - /* If non-resume request is pending, we can overtake it. */ - dev->power.request = retval ? RPM_REQ_NONE : RPM_REQ_RESUME; - return retval; - } - if (retval) - return retval; - - dev->power.request = RPM_REQ_RESUME; - dev->power.request_pending = true; - queue_work(pm_wq, &dev->power.work); - - return retval; -} - -/** - * pm_request_resume - Submit a resume request for given device. - * @dev: Device to resume. */ int pm_request_resume(struct device *dev) { @@ -773,7 +678,7 @@ int pm_request_resume(struct device *dev) int retval; spin_lock_irqsave(&dev->power.lock, flags); - retval = __pm_request_resume(dev); + retval = __pm_runtime_resume(dev, RPM_ASYNC); spin_unlock_irqrestore(&dev->power.lock, flags); return retval; @@ -1088,7 +993,7 @@ void pm_runtime_allow(struct device *dev) dev->power.runtime_auto = true; if (atomic_dec_and_test(&dev->power.usage_count)) - __pm_runtime_idle(dev); + __pm_runtime_idle(dev, 0); out: spin_unlock_irq(&dev->power.lock); |