diff options
Diffstat (limited to 'drivers/base')
| -rw-r--r-- | drivers/base/power/runtime.c | 47 |
1 files changed, 38 insertions, 9 deletions
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 02c652b..656493a 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -250,13 +250,16 @@ static int rpm_callback(int (*cb)(struct device *), struct device *dev) if (!cb) return -ENOSYS; - spin_unlock_irq(&dev->power.lock); + if (dev->power.irq_safe) { + retval = cb(dev); + } else { + spin_unlock_irq(&dev->power.lock); - retval = cb(dev); + retval = cb(dev); - spin_lock_irq(&dev->power.lock); + spin_lock_irq(&dev->power.lock); + } dev->power.runtime_error = retval; - return retval; } @@ -404,7 +407,7 @@ static int rpm_suspend(struct device *dev, int rpmflags) goto out; } - if (parent && !parent->power.ignore_children) { + if (parent && !parent->power.ignore_children && !dev->power.irq_safe) { spin_unlock_irq(&dev->power.lock); pm_request_idle(parent); @@ -527,10 +530,13 @@ static int rpm_resume(struct device *dev, int rpmflags) 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); @@ -553,6 +559,7 @@ static int rpm_resume(struct device *dev, int rpmflags) goto out; goto repeat; } + skip_parent: if (dev->power.no_callbacks) goto no_callback; /* Assume success. */ @@ -584,7 +591,7 @@ static int rpm_resume(struct device *dev, int rpmflags) rpm_idle(dev, RPM_ASYNC); out: - if (parent) { + if (parent && !dev->power.irq_safe) { spin_unlock_irq(&dev->power.lock); pm_runtime_put(parent); @@ -1065,7 +1072,6 @@ EXPORT_SYMBOL_GPL(pm_runtime_allow); * 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) { @@ -1078,6 +1084,27 @@ void pm_runtime_no_callbacks(struct device *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. @@ -1199,4 +1226,6 @@ void pm_runtime_remove(struct device *dev) /* 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); } |