* 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.
*/
#include <linux/sched.h>
#include <linux/pm_runtime.h>
-#include <linux/jiffies.h>
+#include "power.h"
-static int __pm_runtime_resume(struct device *dev, bool from_wq);
-static int __pm_request_idle(struct device *dev);
-static int __pm_request_resume(struct device *dev);
+static int rpm_resume(struct device *dev, int rpmflags);
+static int rpm_suspend(struct device *dev, int rpmflags);
+
+/**
+ * update_pm_runtime_accounting - Update the time accounting of power states
+ * @dev: Device to update the accounting for
+ *
+ * In order to be able to have time accounting of the various power states
+ * (as used by programs such as PowerTOP to show the effectiveness of runtime
+ * PM), we need to track the time spent in each state.
+ * update_pm_runtime_accounting must be called each time before the
+ * runtime_status field is updated, to account the time in the old state
+ * correctly.
+ */
+void update_pm_runtime_accounting(struct device *dev)
+{
+ unsigned long now = jiffies;
+ int delta;
+
+ delta = now - dev->power.accounting_timestamp;
+
+ if (delta < 0)
+ delta = 0;
+
+ dev->power.accounting_timestamp = now;
+
+ if (dev->power.disable_depth > 0)
+ return;
+
+ if (dev->power.runtime_status == RPM_SUSPENDED)
+ dev->power.suspended_jiffies += delta;
+ else
+ dev->power.active_jiffies += delta;
+}
+
+static void __update_runtime_status(struct device *dev, enum rpm_status status)
+{
+ update_pm_runtime_accounting(dev);
+ dev->power.runtime_status = status;
+}
/**
* pm_runtime_deactivate_timer - Deactivate given device's suspend timer.
dev->power.request = RPM_REQ_NONE;
}
-/**
- * __pm_runtime_idle - Notify device bus type if the device can be suspended.
- * @dev: Device to notify the bus type about.
+/*
+ * pm_runtime_autosuspend_expiration - Get a device's autosuspend-delay expiration time.
+ * @dev: Device to handle.
*
- * This function must be called under dev->power.lock with interrupts disabled.
+ * Compute the autosuspend-delay expiration time based on the device's
+ * power.last_busy time. If the delay has already expired or is disabled
+ * (negative) or the power.use_autosuspend flag isn't set, return 0.
+ * Otherwise return the expiration time in jiffies (adjusted to be nonzero).
+ *
+ * This function may be called either with or without dev->power.lock held.
+ * Either way it can be racy, since power.last_busy may be updated at any time.
*/
-static int __pm_runtime_idle(struct device *dev)
- __releases(&dev->power.lock) __acquires(&dev->power.lock)
+unsigned long pm_runtime_autosuspend_expiration(struct device *dev)
+{
+ int autosuspend_delay;
+ long elapsed;
+ unsigned long last_busy;
+ unsigned long expires = 0;
+
+ if (!dev->power.use_autosuspend)
+ goto out;
+
+ autosuspend_delay = ACCESS_ONCE(dev->power.autosuspend_delay);
+ if (autosuspend_delay < 0)
+ goto out;
+
+ last_busy = ACCESS_ONCE(dev->power.last_busy);
+ elapsed = jiffies - last_busy;
+ if (elapsed < 0)
+ goto out; /* jiffies has wrapped around. */
+
+ /*
+ * If the autosuspend_delay is >= 1 second, align the timer by rounding
+ * up to the nearest second.
+ */
+ expires = last_busy + msecs_to_jiffies(autosuspend_delay);
+ if (autosuspend_delay >= 1000)
+ expires = round_jiffies(expires);
+ expires += !expires;
+ if (elapsed >= expires - last_busy)
+ expires = 0; /* Already expired. */
+
+ out:
+ return expires;
+}
+EXPORT_SYMBOL_GPL(pm_runtime_autosuspend_expiration);
+
+/**
+ * rpm_check_suspend_allowed - Test whether a device may be suspended.
+ * @dev: Device to test.
+ */
+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.runtime_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;
+}
+
+/**
+ * rpm_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 rpm_idle(struct device *dev, int rpmflags)
+{
+ int (*callback)(struct device *);
+ 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;
+
+ if (dev->power.no_callbacks) {
+ /* Assume ->runtime_idle() callback would have suspended. */
+ retval = rpm_suspend(dev, rpmflags);
+ goto out;
+ }
+
+ /* 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;
- if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_idle) {
- spin_unlock_irq(&dev->power.lock);
-
- dev->bus->pm->runtime_idle(dev);
-
- spin_lock_irq(&dev->power.lock);
- } else if (dev->type && dev->type->pm && dev->type->pm->runtime_idle) {
- spin_unlock_irq(&dev->power.lock);
-
- dev->type->pm->runtime_idle(dev);
+ if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_idle)
+ callback = dev->bus->pm->runtime_idle;
+ else if (dev->type && dev->type->pm && dev->type->pm->runtime_idle)
+ callback = dev->type->pm->runtime_idle;
+ else if (dev->class && dev->class->pm)
+ callback = dev->class->pm->runtime_idle;
+ else
+ callback = NULL;
- spin_lock_irq(&dev->power.lock);
- } else if (dev->class && dev->class->pm
- && dev->class->pm->runtime_idle) {
+ if (callback) {
spin_unlock_irq(&dev->power.lock);
- dev->class->pm->runtime_idle(dev);
+ callback(dev);
spin_lock_irq(&dev->power.lock);
}
}
/**
- * pm_runtime_idle - Notify device bus type if the device can be suspended.
- * @dev: Device to notify the bus type about.
+ * rpm_callback - Run a given runtime PM callback for a given device.
+ * @cb: Runtime PM callback to run.
+ * @dev: Device to run the callback for.
*/
-int pm_runtime_idle(struct device *dev)
+static int rpm_callback(int (*cb)(struct device *), struct device *dev)
+ __releases(&dev->power.lock) __acquires(&dev->power.lock)
{
int retval;
- spin_lock_irq(&dev->power.lock);
- retval = __pm_runtime_idle(dev);
- spin_unlock_irq(&dev->power.lock);
-
- return retval;
-}
-EXPORT_SYMBOL_GPL(pm_runtime_idle);
-
-
-/**
- * update_pm_runtime_accounting - Update the time accounting of power states
- * @dev: Device to update the accounting for
- *
- * In order to be able to have time accounting of the various power states
- * (as used by programs such as PowerTOP to show the effectiveness of runtime
- * PM), we need to track the time spent in each state.
- * update_pm_runtime_accounting must be called each time before the
- * runtime_status field is updated, to account the time in the old state
- * correctly.
- */
-void update_pm_runtime_accounting(struct device *dev)
-{
- unsigned long now = jiffies;
- int delta;
-
- delta = now - dev->power.accounting_timestamp;
-
- if (delta < 0)
- delta = 0;
+ if (!cb)
+ return -ENOSYS;
- dev->power.accounting_timestamp = now;
-
- if (dev->power.disable_depth > 0)
- return;
+ if (dev->power.irq_safe) {
+ retval = cb(dev);
+ } else {
+ spin_unlock_irq(&dev->power.lock);
- if (dev->power.runtime_status == RPM_SUSPENDED)
- dev->power.suspended_jiffies += delta;
- else
- dev->power.active_jiffies += delta;
-}
+ retval = cb(dev);
-static void __update_runtime_status(struct device *dev, enum rpm_status status)
-{
- update_pm_runtime_accounting(dev);
- dev->power.runtime_status = status;
+ spin_lock_irq(&dev->power.lock);
+ }
+ dev->power.runtime_error = retval;
+ return retval;
}
/**
- * __pm_runtime_suspend - Carry out run-time suspend of given device.
+ * rpm_suspend - Carry out run-time suspend of given device.
* @dev: Device to suspend.
- * @from_wq: If set, the function has been called via pm_wq.
+ * @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, wait
- * for it to finish. 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.
*/
-int __pm_runtime_suspend(struct device *dev, bool from_wq)
+static int rpm_suspend(struct device *dev, int rpmflags)
__releases(&dev->power.lock) __acquires(&dev->power.lock)
{
+ int (*callback)(struct device *);
struct device *parent = NULL;
- bool notify = false;
- int retval = 0;
+ int retval;
- dev_dbg(dev, "__pm_runtime_suspend()%s!\n",
- from_wq ? " from workqueue" : "");
+ 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;
+
+ /* If the autosuspend_delay time hasn't expired yet, reschedule. */
+ if ((rpmflags & RPM_AUTO)
+ && dev->power.runtime_status != RPM_SUSPENDING) {
+ unsigned long expires = pm_runtime_autosuspend_expiration(dev);
+
+ if (expires != 0) {
+ /* Pending requests need to be canceled. */
+ dev->power.request = RPM_REQ_NONE;
+
+ /*
+ * Optimization: If the timer is already running and is
+ * set to expire at or before the autosuspend delay,
+ * avoid the overhead of resetting it. Just let it
+ * expire; pm_suspend_timer_fn() will take care of the
+ * rest.
+ */
+ if (!(dev->power.timer_expires && time_before_eq(
+ dev->power.timer_expires, expires))) {
+ dev->power.timer_expires = expires;
+ mod_timer(&dev->power.suspend_timer, expires);
+ }
+ dev->power.timer_autosuspends = 1;
+ 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 (from_wq) {
+ if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) {
retval = -EINPROGRESS;
goto out;
}
goto repeat;
}
- __update_runtime_status(dev, RPM_SUSPENDING);
dev->power.deferred_resume = false;
+ if (dev->power.no_callbacks)
+ goto no_callback; /* Assume success. */
+
+ /* Carry out an asynchronous or a synchronous suspend. */
+ if (rpmflags & RPM_ASYNC) {
+ dev->power.request = (rpmflags & RPM_AUTO) ?
+ RPM_REQ_AUTOSUSPEND : RPM_REQ_SUSPEND;
+ if (!dev->power.request_pending) {
+ dev->power.request_pending = true;
+ queue_work(pm_wq, &dev->power.work);
+ }
+ goto out;
+ }
- if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_suspend) {
- spin_unlock_irq(&dev->power.lock);
-
- retval = dev->bus->pm->runtime_suspend(dev);
-
- spin_lock_irq(&dev->power.lock);
- dev->power.runtime_error = retval;
- } else if (dev->type && dev->type->pm
- && dev->type->pm->runtime_suspend) {
- spin_unlock_irq(&dev->power.lock);
-
- retval = dev->type->pm->runtime_suspend(dev);
-
- spin_lock_irq(&dev->power.lock);
- dev->power.runtime_error = retval;
- } else if (dev->class && dev->class->pm
- && dev->class->pm->runtime_suspend) {
- spin_unlock_irq(&dev->power.lock);
-
- retval = dev->class->pm->runtime_suspend(dev);
+ __update_runtime_status(dev, RPM_SUSPENDING);
- spin_lock_irq(&dev->power.lock);
- dev->power.runtime_error = retval;
- } else {
- retval = -ENOSYS;
- }
+ if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_suspend)
+ callback = dev->bus->pm->runtime_suspend;
+ else if (dev->type && dev->type->pm && dev->type->pm->runtime_suspend)
+ callback = dev->type->pm->runtime_suspend;
+ else if (dev->class && dev->class->pm)
+ callback = dev->class->pm->runtime_suspend;
+ else
+ callback = NULL;
+ retval = rpm_callback(callback, dev);
if (retval) {
__update_runtime_status(dev, RPM_ACTIVE);
- if (retval == -EAGAIN || retval == -EBUSY) {
- if (dev->power.timer_expires == 0)
- notify = true;
+ dev->power.deferred_resume = 0;
+ if (retval == -EAGAIN || retval == -EBUSY)
dev->power.runtime_error = 0;
- } else {
+ else
pm_runtime_cancel_pending(dev);
- }
} else {
+ no_callback:
__update_runtime_status(dev, RPM_SUSPENDED);
pm_runtime_deactivate_timer(dev);
wake_up_all(&dev->power.wait_queue);
if (dev->power.deferred_resume) {
- __pm_runtime_resume(dev, false);
+ rpm_resume(dev, 0);
retval = -EAGAIN;
goto out;
}
- if (notify)
- __pm_runtime_idle(dev);
-
- if (parent && !parent->power.ignore_children) {
- spin_unlock_irq(&dev->power.lock);
+ /* Maybe the parent is now able to suspend. */
+ if (parent && !parent->power.ignore_children && !dev->power.irq_safe) {
+ spin_unlock(&dev->power.lock);
- pm_request_idle(parent);
+ spin_lock(&parent->power.lock);
+ rpm_idle(parent, RPM_ASYNC);
+ spin_unlock(&parent->power.lock);
- spin_lock_irq(&dev->power.lock);
+ spin_lock(&dev->power.lock);
}
out:
- dev_dbg(dev, "__pm_runtime_suspend() returns %d!\n", retval);
+ dev_dbg(dev, "%s returns %d\n", __func__, retval);
return retval;
}
/**
- * pm_runtime_suspend - Carry out run-time suspend of given device.
- * @dev: Device to suspend.
- */
-int pm_runtime_suspend(struct device *dev)
-{
- int retval;
-
- spin_lock_irq(&dev->power.lock);
- retval = __pm_runtime_suspend(dev, false);
- spin_unlock_irq(&dev->power.lock);
-
- return retval;
-}
-EXPORT_SYMBOL_GPL(pm_runtime_suspend);
-
-/**
- * __pm_runtime_resume - Carry out run-time resume of given device.
+ * rpm_resume - Carry out run-time resume of given device.
* @dev: Device to resume.
- * @from_wq: If set, the function has been called via pm_wq.
+ * @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, wait
- * for it to finish. If there's a suspend running in parallel with this
- * function, wait for it to finish and resume the device. 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.
*/
-int __pm_runtime_resume(struct device *dev, bool from_wq)
+static int rpm_resume(struct device *dev, int rpmflags)
__releases(&dev->power.lock) __acquires(&dev->power.lock)
{
+ int (*callback)(struct device *);
struct device *parent = NULL;
int retval = 0;
- dev_dbg(dev, "__pm_runtime_resume()%s!\n",
- from_wq ? " from workqueue" : "");
+ 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;
- }
- pm_runtime_cancel_pending(dev);
+ /*
+ * Other scheduled or pending requests need to be canceled. Small
+ * optimization: If an autosuspend timer is running, leave it running
+ * rather than cancelling it now only to restart it again in the near
+ * future.
+ */
+ dev->power.request = RPM_REQ_NONE;
+ if (!dev->power.timer_autosuspends)
+ pm_runtime_deactivate_timer(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 (from_wq) {
+ 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;
}
goto repeat;
}
+ /*
+ * See if we can skip waking up the parent. This is safe only if
+ * power.no_callbacks is set, because otherwise we don't know whether
+ * the resume will actually succeed.
+ */
+ if (dev->power.no_callbacks && !parent && dev->parent) {
+ spin_lock_nested(&dev->parent->power.lock, SINGLE_DEPTH_NESTING);
+ if (dev->parent->power.disable_depth > 0
+ || dev->parent->power.ignore_children
+ || dev->parent->power.runtime_status == RPM_ACTIVE) {
+ atomic_inc(&dev->parent->power.child_count);
+ spin_unlock(&dev->parent->power.lock);
+ goto no_callback; /* Assume success. */
+ }
+ spin_unlock(&dev->parent->power.lock);
+ }
+
+ /* 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
- * necessary.
+ * Increment the parent's usage counter and resume it if
+ * necessary. Not needed if dev is irq-safe; then the
+ * parent is permanently resumed.
*/
parent = dev->parent;
+ if (dev->power.irq_safe)
+ goto skip_parent;
spin_unlock(&dev->power.lock);
pm_runtime_get_noresume(parent);
*/
if (!parent->power.disable_depth
&& !parent->power.ignore_children) {
- __pm_runtime_resume(parent, false);
+ rpm_resume(parent, 0);
if (parent->power.runtime_status != RPM_ACTIVE)
retval = -EBUSY;
}
goto out;
goto repeat;
}
+ skip_parent:
- __update_runtime_status(dev, RPM_RESUMING);
-
- if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_resume) {
- spin_unlock_irq(&dev->power.lock);
-
- retval = dev->bus->pm->runtime_resume(dev);
-
- spin_lock_irq(&dev->power.lock);
- dev->power.runtime_error = retval;
- } else if (dev->type && dev->type->pm
- && dev->type->pm->runtime_resume) {
- spin_unlock_irq(&dev->power.lock);
-
- retval = dev->type->pm->runtime_resume(dev);
-
- spin_lock_irq(&dev->power.lock);
- dev->power.runtime_error = retval;
- } else if (dev->class && dev->class->pm
- && dev->class->pm->runtime_resume) {
- spin_unlock_irq(&dev->power.lock);
+ if (dev->power.no_callbacks)
+ goto no_callback; /* Assume success. */
- retval = dev->class->pm->runtime_resume(dev);
+ __update_runtime_status(dev, RPM_RESUMING);
- spin_lock_irq(&dev->power.lock);
- dev->power.runtime_error = retval;
- } else {
- retval = -ENOSYS;
- }
+ if (dev->bus && dev->bus->pm && dev->bus->pm->runtime_resume)
+ callback = dev->bus->pm->runtime_resume;
+ else if (dev->type && dev->type->pm && dev->type->pm->runtime_resume)
+ callback = dev->type->pm->runtime_resume;
+ else if (dev->class && dev->class->pm)
+ callback = dev->class->pm->runtime_resume;
+ else
+ callback = NULL;
+ retval = rpm_callback(callback, dev);
if (retval) {
__update_runtime_status(dev, RPM_SUSPENDED);
pm_runtime_cancel_pending(dev);
} else {
+ no_callback:
__update_runtime_status(dev, RPM_ACTIVE);
if (parent)
atomic_inc(&parent->power.child_count);
wake_up_all(&dev->power.wait_queue);
if (!retval)
- __pm_request_idle(dev);
+ rpm_idle(dev, RPM_ASYNC);
out:
- if (parent) {
+ if (parent && !dev->power.irq_safe) {
spin_unlock_irq(&dev->power.lock);
pm_runtime_put(parent);
spin_lock_irq(&dev->power.lock);
}
- dev_dbg(dev, "__pm_runtime_resume() returns %d!\n", retval);
+ dev_dbg(dev, "%s returns %d\n", __func__, retval);
return retval;
}
-/**
- * pm_runtime_resume - Carry out run-time resume of given device.
- * @dev: Device to suspend.
- */
-int pm_runtime_resume(struct device *dev)
-{
- int retval;
-
- spin_lock_irq(&dev->power.lock);
- retval = __pm_runtime_resume(dev, false);
- spin_unlock_irq(&dev->power.lock);
-
- return retval;
-}
-EXPORT_SYMBOL_GPL(pm_runtime_resume);
-
/**
* pm_runtime_work - Universal run-time PM work function.
* @work: Work structure used for scheduling the execution of this function.
case RPM_REQ_NONE:
break;
case RPM_REQ_IDLE:
- __pm_runtime_idle(dev);
+ rpm_idle(dev, RPM_NOWAIT);
break;
case RPM_REQ_SUSPEND:
- __pm_runtime_suspend(dev, true);
+ rpm_suspend(dev, RPM_NOWAIT);
+ break;
+ case RPM_REQ_AUTOSUSPEND:
+ rpm_suspend(dev, RPM_NOWAIT | RPM_AUTO);
break;
case RPM_REQ_RESUME:
- __pm_runtime_resume(dev, true);
+ rpm_resume(dev, RPM_NOWAIT);
break;
}
spin_unlock_irq(&dev->power.lock);
}
-/**
- * __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.
- */
-int pm_request_idle(struct device *dev)
-{
- unsigned long flags;
- int retval;
-
- spin_lock_irqsave(&dev->power.lock, flags);
- retval = __pm_request_idle(dev);
- spin_unlock_irqrestore(&dev->power.lock, flags);
-
- return retval;
-}
-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)
{
/* 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);
+ rpm_suspend(dev, dev->power.timer_autosuspends ?
+ (RPM_ASYNC | RPM_AUTO) : RPM_ASYNC);
}
spin_unlock_irqrestore(&dev->power.lock, flags);
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 = rpm_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;
+ dev->power.timer_autosuspends = 0;
mod_timer(&dev->power.suspend_timer, dev->power.timer_expires);
out:
EXPORT_SYMBOL_GPL(pm_schedule_suspend);
/**
- * pm_request_resume - Submit a resume request for given device.
- * @dev: Device to resume.
+ * __pm_runtime_idle - Entry point for run-time idle operations.
+ * @dev: Device to send idle notification for.
+ * @rpmflags: Flag bits.
*
- * This function must be called under dev->power.lock with interrupts disabled.
+ * If the RPM_GET_PUT flag is set, decrement the device's usage count and
+ * return immediately if it is larger than zero. Then carry out an idle
+ * notification, either synchronous or asynchronous.
+ *
+ * This routine may be called in atomic context if the RPM_ASYNC flag is set.
*/
-static int __pm_request_resume(struct device *dev)
+int __pm_runtime_idle(struct device *dev, int rpmflags)
{
- 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);
+ unsigned long flags;
+ int retval;
- 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 (rpmflags & RPM_GET_PUT) {
+ if (!atomic_dec_and_test(&dev->power.usage_count))
+ return 0;
}
- if (retval)
- return retval;
- dev->power.request = RPM_REQ_RESUME;
- dev->power.request_pending = true;
- queue_work(pm_wq, &dev->power.work);
+ spin_lock_irqsave(&dev->power.lock, flags);
+ retval = rpm_idle(dev, rpmflags);
+ spin_unlock_irqrestore(&dev->power.lock, flags);
return retval;
}
+EXPORT_SYMBOL_GPL(__pm_runtime_idle);
/**
- * pm_request_resume - Submit a resume request for given device.
- * @dev: Device to resume.
+ * __pm_runtime_suspend - Entry point for run-time put/suspend operations.
+ * @dev: Device to suspend.
+ * @rpmflags: Flag bits.
+ *
+ * If the RPM_GET_PUT flag is set, decrement the device's usage count and
+ * return immediately if it is larger than zero. Then carry out a suspend,
+ * either synchronous or asynchronous.
+ *
+ * This routine may be called in atomic context if the RPM_ASYNC flag is set.
*/
-int pm_request_resume(struct device *dev)
+int __pm_runtime_suspend(struct device *dev, int rpmflags)
{
unsigned long flags;
int retval;
+ if (rpmflags & RPM_GET_PUT) {
+ if (!atomic_dec_and_test(&dev->power.usage_count))
+ return 0;
+ }
+
spin_lock_irqsave(&dev->power.lock, flags);
- retval = __pm_request_resume(dev);
+ retval = rpm_suspend(dev, rpmflags);
spin_unlock_irqrestore(&dev->power.lock, flags);
return retval;
}
-EXPORT_SYMBOL_GPL(pm_request_resume);
+EXPORT_SYMBOL_GPL(__pm_runtime_suspend);
/**
- * __pm_runtime_get - Reference count a device and wake it up, if necessary.
- * @dev: Device to handle.
- * @sync: If set and the device is suspended, resume it synchronously.
+ * __pm_runtime_resume - Entry point for run-time resume operations.
+ * @dev: Device to resume.
+ * @rpmflags: Flag bits.
+ *
+ * If the RPM_GET_PUT flag is set, increment the device's usage count. Then
+ * carry out a resume, either synchronous or asynchronous.
*
- * Increment the usage count of the device and resume it or submit a resume
- * request for it, depending on the value of @sync.
+ * This routine may be called in atomic context if the RPM_ASYNC flag is set.
*/
-int __pm_runtime_get(struct device *dev, bool sync)
+int __pm_runtime_resume(struct device *dev, int rpmflags)
{
+ unsigned long flags;
int retval;
- atomic_inc(&dev->power.usage_count);
- retval = sync ? pm_runtime_resume(dev) : pm_request_resume(dev);
-
- return retval;
-}
-EXPORT_SYMBOL_GPL(__pm_runtime_get);
-
-/**
- * __pm_runtime_put - Decrement the device's usage counter and notify its bus.
- * @dev: Device to handle.
- * @sync: If the device's bus type is to be notified, do that synchronously.
- *
- * Decrement the usage count of the device and if it reaches zero, carry out a
- * synchronous idle notification or submit an idle notification request for it,
- * depending on the value of @sync.
- */
-int __pm_runtime_put(struct device *dev, bool sync)
-{
- int retval = 0;
+ if (rpmflags & RPM_GET_PUT)
+ atomic_inc(&dev->power.usage_count);
- if (atomic_dec_and_test(&dev->power.usage_count))
- retval = sync ? pm_runtime_idle(dev) : pm_request_idle(dev);
+ spin_lock_irqsave(&dev->power.lock, flags);
+ retval = rpm_resume(dev, rpmflags);
+ spin_unlock_irqrestore(&dev->power.lock, flags);
return retval;
}
-EXPORT_SYMBOL_GPL(__pm_runtime_put);
+EXPORT_SYMBOL_GPL(__pm_runtime_resume);
/**
* __pm_runtime_set_status - Set run-time PM status of a device.
if (dev->power.request_pending
&& dev->power.request == RPM_REQ_RESUME) {
- __pm_runtime_resume(dev, false);
+ rpm_resume(dev, 0);
retval = 1;
}
*/
pm_runtime_get_noresume(dev);
- __pm_runtime_resume(dev, false);
+ rpm_resume(dev, 0);
pm_runtime_put_noidle(dev);
}
dev->power.runtime_auto = false;
atomic_inc(&dev->power.usage_count);
- __pm_runtime_resume(dev, false);
+ rpm_resume(dev, 0);
out:
spin_unlock_irq(&dev->power.lock);
dev->power.runtime_auto = true;
if (atomic_dec_and_test(&dev->power.usage_count))
- __pm_runtime_idle(dev);
+ rpm_idle(dev, RPM_AUTO);
out:
spin_unlock_irq(&dev->power.lock);
}
EXPORT_SYMBOL_GPL(pm_runtime_allow);
+/**
+ * pm_runtime_no_callbacks - Ignore run-time PM callbacks for a device.
+ * @dev: Device to handle.
+ *
+ * Set the power.no_callbacks flag, which tells the PM core that this
+ * device is power-managed through its parent and has no run-time PM
+ * callbacks of its own. The run-time sysfs attributes will be removed.
+ */
+void pm_runtime_no_callbacks(struct device *dev)
+{
+ spin_lock_irq(&dev->power.lock);
+ dev->power.no_callbacks = 1;
+ spin_unlock_irq(&dev->power.lock);
+ if (device_is_registered(dev))
+ rpm_sysfs_remove(dev);
+}
+EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks);
+
+/**
+ * pm_runtime_irq_safe - Leave interrupts disabled during callbacks.
+ * @dev: Device to handle
+ *
+ * Set the power.irq_safe flag, which tells the PM core that the
+ * ->runtime_suspend() and ->runtime_resume() callbacks for this device should
+ * always be invoked with the spinlock held and interrupts disabled. It also
+ * causes the parent's usage counter to be permanently incremented, preventing
+ * the parent from runtime suspending -- otherwise an irq-safe child might have
+ * to wait for a non-irq-safe parent.
+ */
+void pm_runtime_irq_safe(struct device *dev)
+{
+ if (dev->parent)
+ pm_runtime_get_sync(dev->parent);
+ spin_lock_irq(&dev->power.lock);
+ dev->power.irq_safe = 1;
+ spin_unlock_irq(&dev->power.lock);
+}
+EXPORT_SYMBOL_GPL(pm_runtime_irq_safe);
+
+/**
+ * update_autosuspend - Handle a change to a device's autosuspend settings.
+ * @dev: Device to handle.
+ * @old_delay: The former autosuspend_delay value.
+ * @old_use: The former use_autosuspend value.
+ *
+ * Prevent runtime suspend if the new delay is negative and use_autosuspend is
+ * set; otherwise allow it. Send an idle notification if suspends are allowed.
+ *
+ * This function must be called under dev->power.lock with interrupts disabled.
+ */
+static void update_autosuspend(struct device *dev, int old_delay, int old_use)
+{
+ int delay = dev->power.autosuspend_delay;
+
+ /* Should runtime suspend be prevented now? */
+ if (dev->power.use_autosuspend && delay < 0) {
+
+ /* If it used to be allowed then prevent it. */
+ if (!old_use || old_delay >= 0) {
+ atomic_inc(&dev->power.usage_count);
+ rpm_resume(dev, 0);
+ }
+ }
+
+ /* Runtime suspend should be allowed now. */
+ else {
+
+ /* If it used to be prevented then allow it. */
+ if (old_use && old_delay < 0)
+ atomic_dec(&dev->power.usage_count);
+
+ /* Maybe we can autosuspend now. */
+ rpm_idle(dev, RPM_AUTO);
+ }
+}
+
+/**
+ * pm_runtime_set_autosuspend_delay - Set a device's autosuspend_delay value.
+ * @dev: Device to handle.
+ * @delay: Value of the new delay in milliseconds.
+ *
+ * Set the device's power.autosuspend_delay value. If it changes to negative
+ * and the power.use_autosuspend flag is set, prevent run-time suspends. If it
+ * changes the other way, allow run-time suspends.
+ */
+void pm_runtime_set_autosuspend_delay(struct device *dev, int delay)
+{
+ int old_delay, old_use;
+
+ spin_lock_irq(&dev->power.lock);
+ old_delay = dev->power.autosuspend_delay;
+ old_use = dev->power.use_autosuspend;
+ dev->power.autosuspend_delay = delay;
+ update_autosuspend(dev, old_delay, old_use);
+ spin_unlock_irq(&dev->power.lock);
+}
+EXPORT_SYMBOL_GPL(pm_runtime_set_autosuspend_delay);
+
+/**
+ * __pm_runtime_use_autosuspend - Set a device's use_autosuspend flag.
+ * @dev: Device to handle.
+ * @use: New value for use_autosuspend.
+ *
+ * Set the device's power.use_autosuspend flag, and allow or prevent run-time
+ * suspends as needed.
+ */
+void __pm_runtime_use_autosuspend(struct device *dev, bool use)
+{
+ int old_delay, old_use;
+
+ spin_lock_irq(&dev->power.lock);
+ old_delay = dev->power.autosuspend_delay;
+ old_use = dev->power.use_autosuspend;
+ dev->power.use_autosuspend = use;
+ update_autosuspend(dev, old_delay, old_use);
+ spin_unlock_irq(&dev->power.lock);
+}
+EXPORT_SYMBOL_GPL(__pm_runtime_use_autosuspend);
+
/**
* pm_runtime_init - Initialize run-time PM fields in given device object.
* @dev: Device object to initialize.
*/
void pm_runtime_init(struct device *dev)
{
- spin_lock_init(&dev->power.lock);
-
dev->power.runtime_status = RPM_SUSPENDED;
dev->power.idle_notification = false;
/* Change the status back to 'suspended' to match the initial status. */
if (dev->power.runtime_status == RPM_ACTIVE)
pm_runtime_set_suspended(dev);
+ if (dev->power.irq_safe && dev->parent)
+ pm_runtime_put_sync(dev->parent);
}
projects / mv-sheeva.git / blobdiff