1 files changed, 105 insertions, 86 deletions

diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 1b1a786b7dec..e0dc4071e088 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -21,6 +21,7 @@
 #include <linux/kallsyms.h>
 #include <linux/mutex.h>
 #include <linux/pm.h>
+#include <linux/pm_runtime.h>
 #include <linux/resume-trace.h>
 #include <linux/rwsem.h>
 #include <linux/interrupt.h>
@@ -49,7 +50,17 @@ static DEFINE_MUTEX(dpm_list_mtx);
 static bool transition_started;
 
 /**
- *      device_pm_lock - lock the list of active devices used by the PM core
+ * device_pm_init - Initialize the PM-related part of a device object.
+ * @dev: Device object being initialized.
+ */
+void device_pm_init(struct device *dev)
+{
+        dev->power.status = DPM_ON;
+        pm_runtime_init(dev);
+}
+
+/**
+ * device_pm_lock - Lock the list of active devices used by the PM core.
  */
 void device_pm_lock(void)
 {
@@ -57,7 +68,7 @@ void device_pm_lock(void)
 }
 
 /**
- *      device_pm_unlock - unlock the list of active devices used by the PM core
+ * device_pm_unlock - Unlock the list of active devices used by the PM core.
  */
 void device_pm_unlock(void)
 {
@@ -65,8 +76,8 @@ void device_pm_unlock(void)
 }
 
 /**
- *      device_pm_add - add a device to the list of active devices
- *      @dev:   Device to be added to the list
+ * device_pm_add - Add a device to the PM core's list of active devices.
+ * @dev: Device to add to the list.
  */
 void device_pm_add(struct device *dev)
 {
@@ -92,10 +103,8 @@ void device_pm_add(struct device *dev)
 }
 
 /**
- *      device_pm_remove - remove a device from the list of active devices
- *      @dev:   Device to be removed from the list
- *
- *      This function also removes the device's PM-related sysfs attributes.
+ * device_pm_remove - Remove a device from the PM core's list of active devices.
+ * @dev: Device to be removed from the list.
  */
 void device_pm_remove(struct device *dev)
 {
@@ -105,12 +114,13 @@ void device_pm_remove(struct device *dev)
         mutex_lock(&dpm_list_mtx);
         list_del_init(&dev->power.entry);
         mutex_unlock(&dpm_list_mtx);
+        pm_runtime_remove(dev);
 }
 
 /**
- *      device_pm_move_before - move device in dpm_list
- *      @deva:  Device to move in dpm_list
- *      @devb:  Device @deva should come before
+ * device_pm_move_before - Move device in the PM core's list of active devices.
+ * @deva: Device to move in dpm_list.
+ * @devb: Device @deva should come before.
  */
 void device_pm_move_before(struct device *deva, struct device *devb)
 {
@@ -124,9 +134,9 @@ void device_pm_move_before(struct device *deva, struct device *devb)
 }
 
 /**
- *      device_pm_move_after - move device in dpm_list
- *      @deva:  Device to move in dpm_list
- *      @devb:  Device @deva should come after
+ * device_pm_move_after - Move device in the PM core's list of active devices.
+ * @deva: Device to move in dpm_list.
+ * @devb: Device @deva should come after.
  */
 void device_pm_move_after(struct device *deva, struct device *devb)
 {
@@ -140,8 +150,8 @@ void device_pm_move_after(struct device *deva, struct device *devb)
 }
 
 /**
- *      device_pm_move_last - move device to end of dpm_list
- *      @dev:   Device to move in dpm_list
+ * device_pm_move_last - Move device to end of the PM core's list of devices.
+ * @dev: Device to move in dpm_list.
  */
 void device_pm_move_last(struct device *dev)
 {
@@ -152,10 +162,10 @@ void device_pm_move_last(struct device *dev)
 }
 
 /**
- *      pm_op - execute the PM operation appropiate for given PM event
- *      @dev:   Device.
- *      @ops:   PM operations to choose from.
- *      @state: PM transition of the system being carried out.
+ * pm_op - Execute the PM operation appropriate for given PM event.
+ * @dev: Device to handle.
+ * @ops: PM operations to choose from.
+ * @state: PM transition of the system being carried out.
  */
 static int pm_op(struct device *dev,
                  const struct dev_pm_ops *ops,
@@ -213,13 +223,13 @@ static int pm_op(struct device *dev,
 }
 
 /**
- *      pm_noirq_op - execute the PM operation appropiate for given PM event
- *      @dev:   Device.
- *      @ops:   PM operations to choose from.
- *      @state: PM transition of the system being carried out.
+ * pm_noirq_op - Execute the PM operation appropriate for given PM event.
+ * @dev: Device to handle.
+ * @ops: PM operations to choose from.
+ * @state: PM transition of the system being carried out.
  *
- *      The operation is executed with interrupts disabled by the only remaining
- *      functional CPU in the system.
+ * The driver of @dev will not receive interrupts while this function is being
+ * executed.
  */
 static int pm_noirq_op(struct device *dev,
                         const struct dev_pm_ops *ops,
@@ -317,11 +327,12 @@ static void pm_dev_err(struct device *dev, pm_message_t state, char *info,
 /*------------------------- Resume routines -------------------------*/
 
 /**
- *      device_resume_noirq - Power on one device (early resume).
- *      @dev:   Device.
- *      @state: PM transition of the system being carried out.
+ * device_resume_noirq - Execute an "early resume" callback for given device.
+ * @dev: Device to handle.
+ * @state: PM transition of the system being carried out.
  *
- *      Must be called with interrupts disabled.
+ * The driver of @dev will not receive interrupts while this function is being
+ * executed.
  */
 static int device_resume_noirq(struct device *dev, pm_message_t state)
 {
@@ -343,20 +354,18 @@ static int device_resume_noirq(struct device *dev, pm_message_t state)
 }
 
 /**
- *      dpm_resume_noirq - Power on all regular (non-sysdev) devices.
- *      @state: PM transition of the system being carried out.
- *
- *      Call the "noirq" resume handlers for all devices marked as
- *      DPM_OFF_IRQ and enable device drivers to receive interrupts.
+ * dpm_resume_noirq - Execute "early resume" callbacks for non-sysdev devices.
+ * @state: PM transition of the system being carried out.
  *
- *      Must be called under dpm_list_mtx.  Device drivers should not receive
- *      interrupts while it's being executed.
+ * Call the "noirq" resume handlers for all devices marked as DPM_OFF_IRQ and
+ * enable device drivers to receive interrupts.
  */
 void dpm_resume_noirq(pm_message_t state)
 {
         struct device *dev;
 
         mutex_lock(&dpm_list_mtx);
+        transition_started = false;
         list_for_each_entry(dev, &dpm_list, power.entry)
                 if (dev->power.status > DPM_OFF) {
                         int error;
@@ -372,9 +381,9 @@ void dpm_resume_noirq(pm_message_t state)
 EXPORT_SYMBOL_GPL(dpm_resume_noirq);
 
 /**
- *      device_resume - Restore state for one device.
- *      @dev:   Device.
- *      @state: PM transition of the system being carried out.
+ * device_resume - Execute "resume" callbacks for given device.
+ * @dev: Device to handle.
+ * @state: PM transition of the system being carried out.
  */
 static int device_resume(struct device *dev, pm_message_t state)
 {
@@ -423,11 +432,11 @@ static int device_resume(struct device *dev, pm_message_t state)
 }
 
 /**
- *      dpm_resume - Resume every device.
- *      @state: PM transition of the system being carried out.
+ * dpm_resume - Execute "resume" callbacks for non-sysdev devices.
+ * @state: PM transition of the system being carried out.
  *
- *      Execute the appropriate "resume" callback for all devices the status of
- *      which indicates that they are inactive.
+ * Execute the appropriate "resume" callback for all devices whose status
+ * indicates that they are suspended.
  */
 static void dpm_resume(pm_message_t state)
 {
@@ -435,7 +444,6 @@ static void dpm_resume(pm_message_t state)
 
         INIT_LIST_HEAD(&list);
         mutex_lock(&dpm_list_mtx);
-        transition_started = false;
         while (!list_empty(&dpm_list)) {
                 struct device *dev = to_device(dpm_list.next);
 
@@ -464,9 +472,9 @@ static void dpm_resume(pm_message_t state)
 }
 
 /**
- *      device_complete - Complete a PM transition for given device
- *      @dev:   Device.
- *      @state: PM transition of the system being carried out.
+ * device_complete - Complete a PM transition for given device.
+ * @dev: Device to handle.
+ * @state: PM transition of the system being carried out.
  */
 static void device_complete(struct device *dev, pm_message_t state)
 {
@@ -491,11 +499,11 @@ static void device_complete(struct device *dev, pm_message_t state)
 }
 
 /**
- *      dpm_complete - Complete a PM transition for all devices.
- *      @state: PM transition of the system being carried out.
+ * dpm_complete - Complete a PM transition for all non-sysdev devices.
+ * @state: PM transition of the system being carried out.
  *
- *      Execute the ->complete() callbacks for all devices that are not marked
- *      as DPM_ON.
+ * Execute the ->complete() callbacks for all devices whose PM status is not
+ * DPM_ON (this allows new devices to be registered).
  */
 static void dpm_complete(pm_message_t state)
 {
@@ -512,6 +520,7 @@ static void dpm_complete(pm_message_t state)
                         mutex_unlock(&dpm_list_mtx);
 
                         device_complete(dev, state);
+                        pm_runtime_put_noidle(dev);
 
                         mutex_lock(&dpm_list_mtx);
                 }
@@ -524,11 +533,11 @@ static void dpm_complete(pm_message_t state)
 }
 
 /**
- *      dpm_resume_end - Restore state of each device in system.
- *      @state: PM transition of the system being carried out.
+ * dpm_resume_end - Execute "resume" callbacks and complete system transition.
+ * @state: PM transition of the system being carried out.
  *
- *      Resume all the devices, unlock them all, and allow new
- *      devices to be registered once again.
+ * Execute "resume" callbacks for all devices and complete the PM transition of
+ * the system.
  */
 void dpm_resume_end(pm_message_t state)
 {
@@ -542,9 +551,11 @@ EXPORT_SYMBOL_GPL(dpm_resume_end);
 /*------------------------- Suspend routines -------------------------*/
 
 /**
- *      resume_event - return a PM message representing the resume event
- *                     corresponding to given sleep state.
- *      @sleep_state: PM message representing a sleep state.
+ * resume_event - Return a "resume" message for given "suspend" sleep state.
+ * @sleep_state: PM message representing a sleep state.
+ *
+ * Return a PM message representing the resume event corresponding to given
+ * sleep state.
  */
 static pm_message_t resume_event(pm_message_t sleep_state)
 {
@@ -561,11 +572,12 @@ static pm_message_t resume_event(pm_message_t sleep_state)
 }
 
 /**
- *      device_suspend_noirq - Shut down one device (late suspend).
- *      @dev:   Device.
- *      @state: PM transition of the system being carried out.
+ * device_suspend_noirq - Execute a "late suspend" callback for given device.
+ * @dev: Device to handle.
+ * @state: PM transition of the system being carried out.
  *
- *      This is called with interrupts off and only a single CPU running.
+ * The driver of @dev will not receive interrupts while this function is being
+ * executed.
  */
 static int device_suspend_noirq(struct device *dev, pm_message_t state)
 {
@@ -582,13 +594,11 @@ static int device_suspend_noirq(struct device *dev, pm_message_t state)
 }
 
 /**
- *      dpm_suspend_noirq - Power down all regular (non-sysdev) devices.
- *      @state: PM transition of the system being carried out.
- *
- *      Prevent device drivers from receiving interrupts and call the "noirq"
- *      suspend handlers.
+ * dpm_suspend_noirq - Execute "late suspend" callbacks for non-sysdev devices.
+ * @state: PM transition of the system being carried out.
  *
- *      Must be called under dpm_list_mtx.
+ * Prevent device drivers from receiving interrupts and call the "noirq" suspend
+ * handlers for all non-sysdev devices.
  */
 int dpm_suspend_noirq(pm_message_t state)
 {
@@ -613,9 +623,9 @@ int dpm_suspend_noirq(pm_message_t state)
 EXPORT_SYMBOL_GPL(dpm_suspend_noirq);
 
 /**
- *      device_suspend - Save state of one device.
- *      @dev:   Device.
- *      @state: PM transition of the system being carried out.
+ * device_suspend - Execute "suspend" callbacks for given device.
+ * @dev: Device to handle.
+ * @state: PM transition of the system being carried out.
  */
 static int device_suspend(struct device *dev, pm_message_t state)
 {
@@ -662,10 +672,8 @@ static int device_suspend(struct device *dev, pm_message_t state)
 }
 
 /**
- *      dpm_suspend - Suspend every device.
- *      @state: PM transition of the system being carried out.
- *
- *      Execute the appropriate "suspend" callbacks for all devices.
+ * dpm_suspend - Execute "suspend" callbacks for all non-sysdev devices.
+ * @state: PM transition of the system being carried out.
  */
 static int dpm_suspend(pm_message_t state)
 {
@@ -699,9 +707,12 @@ static int dpm_suspend(pm_message_t state)
 }
 
 /**
- *      device_prepare - Execute the ->prepare() callback(s) for given device.
- *      @dev:   Device.
- *      @state: PM transition of the system being carried out.
+ * device_prepare - Prepare a device for system power transition.
+ * @dev: Device to handle.
+ * @state: PM transition of the system being carried out.
+ *
+ * Execute the ->prepare() callback(s) for given device.  No new children of the
+ * device may be registered after this function has returned.
  */
 static int device_prepare(struct device *dev, pm_message_t state)
 {
@@ -737,10 +748,10 @@ static int device_prepare(struct device *dev, pm_message_t state)
 }
 
 /**
- *      dpm_prepare - Prepare all devices for a PM transition.
- *      @state: PM transition of the system being carried out.
+ * dpm_prepare - Prepare all non-sysdev devices for a system PM transition.
+ * @state: PM transition of the system being carried out.
  *
- *      Execute the ->prepare() callback for all devices.
+ * Execute the ->prepare() callback(s) for all devices.
  */
 static int dpm_prepare(pm_message_t state)
 {
@@ -757,7 +768,14 @@ static int dpm_prepare(pm_message_t state)
                 dev->power.status = DPM_PREPARING;
                 mutex_unlock(&dpm_list_mtx);
 
-                error = device_prepare(dev, state);
+                pm_runtime_get_noresume(dev);
+                if (pm_runtime_barrier(dev) && device_may_wakeup(dev)) {
+                        /* Wake-up requested during system sleep transition. */
+                        pm_runtime_put_noidle(dev);
+                        error = -EBUSY;
+                } else {
+                        error = device_prepare(dev, state);
+                }
 
                 mutex_lock(&dpm_list_mtx);
                 if (error) {
@@ -784,10 +802,11 @@ static int dpm_prepare(pm_message_t state)
 }
 
 /**
- *      dpm_suspend_start - Save state and stop all devices in system.
- *      @state: PM transition of the system being carried out.
+ * dpm_suspend_start - Prepare devices for PM transition and suspend them.
+ * @state: PM transition of the system being carried out.
  *
- *      Prepare and suspend all devices.
+ * Prepare all non-sysdev devices for system PM transition and execute "suspend"
+ * callbacks for them.
  */
 int dpm_suspend_start(pm_message_t state)
 {