1 files changed, 38 insertions, 47 deletions

diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 6ed8b9326629..7eea95d490e6 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -35,8 +35,6 @@
 #include <linux/timer.h>
 #include <linux/wakeup_reason.h>
 
-#include <asm/current.h>
-
 #include "../base.h"
 #include "power.h"
 
@@ -62,12 +60,6 @@ struct suspend_stats suspend_stats;
 static DEFINE_MUTEX(dpm_list_mtx);
 static pm_message_t pm_transition;
 
-static void dpm_drv_timeout(unsigned long data);
-struct dpm_drv_wd_data {
-	struct device *dev;
-	struct task_struct *tsk;
-};
-
 static int async_error;
 
 static char *pm_verb(int event)
@@ -134,6 +126,7 @@ void device_pm_add(struct device *dev)
 {
 	pr_debug("PM: Adding info for %s:%s\n",
 		 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
+	device_pm_check_callbacks(dev);
 	mutex_lock(&dpm_list_mtx);
 	if (dev->parent && dev->parent->power.is_prepared)
 		dev_warn(dev, "parent %s should not be sleeping\n",
@@ -156,6 +149,7 @@ void device_pm_remove(struct device *dev)
 	mutex_unlock(&dpm_list_mtx);
 	device_wakeup_disable(dev);
 	pm_runtime_remove(dev);
+	device_pm_check_callbacks(dev);
 }
 
 /**
@@ -839,30 +833,6 @@ static void async_resume(void *data, async_cookie_t cookie)
 }
 
 /**
- *	dpm_drv_timeout - Driver suspend / resume watchdog handler
- *	@data: struct device which timed out
- *
- * 	Called when a driver has timed out suspending or resuming.
- * 	There's not much we can do here to recover so
- * 	BUG() out for a crash-dump
- *
- */
-static void dpm_drv_timeout(unsigned long data)
-{
-	struct dpm_drv_wd_data *wd_data = (void *)data;
-	struct device *dev = wd_data->dev;
-	struct task_struct *tsk = wd_data->tsk;
-
-	printk(KERN_EMERG "**** DPM device timeout: %s (%s)\n", dev_name(dev),
-	       (dev->driver ? dev->driver->name : "no driver"));
-
-	printk(KERN_EMERG "dpm suspend stack:\n");
-	show_stack(tsk, NULL);
-
-	BUG();
-}
-
-/**
  * dpm_resume - Execute "resume" callbacks for non-sysdev devices.
  * @state: PM transition of the system being carried out.
  *
@@ -1295,14 +1265,15 @@ int dpm_suspend_late(pm_message_t state)
 		error = device_suspend_late(dev);
 
 		mutex_lock(&dpm_list_mtx);
+		if (!list_empty(&dev->power.entry))
+			list_move(&dev->power.entry, &dpm_late_early_list);
+
 		if (error) {
 			pm_dev_err(dev, state, " late", error);
 			dpm_save_failed_dev(dev_name(dev));
 			put_device(dev);
 			break;
 		}
-		if (!list_empty(&dev->power.entry))
-			list_move(&dev->power.entry, &dpm_late_early_list);
 		put_device(dev);
 
 		if (async_error)
@@ -1380,8 +1351,6 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
 	pm_callback_t callback = NULL;
 	char *info = NULL;
 	int error = 0;
-	struct timer_list timer;
-	struct dpm_drv_wd_data data;
 	char suspend_abort[MAX_SUSPEND_ABORT_LEN];
 	DECLARE_DPM_WATCHDOG_ON_STACK(wd);
 
@@ -1412,14 +1381,6 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
 
 	if (dev->power.syscore)
 		goto Complete;
-	
-	data.dev = dev;
-	data.tsk = current;
-	init_timer_on_stack(&timer);
-	timer.expires = jiffies + HZ * 12;
-	timer.function = dpm_drv_timeout;
-	timer.data = (unsigned long)&data;
-	add_timer(&timer);
 
 	if (dev->power.direct_complete) {
 		if (pm_runtime_status_suspended(dev)) {
@@ -1500,9 +1461,6 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
 	device_unlock(dev);
 	dpm_watchdog_clear(&wd);
 
-	del_timer_sync(&timer);
-	destroy_timer_on_stack(&timer);
-
  Complete:
 	complete_all(&dev->power.completion);
 	if (error)
@@ -1619,6 +1577,11 @@ static int device_prepare(struct device *dev, pm_message_t state)
 
 	dev->power.wakeup_path = device_may_wakeup(dev);
 
+	if (dev->power.no_pm_callbacks) {
+		ret = 1;	/* Let device go direct_complete */
+		goto unlock;
+	}
+
 	if (dev->pm_domain) {
 		info = "preparing power domain ";
 		callback = dev->pm_domain->ops.prepare;
@@ -1641,6 +1604,7 @@ static int device_prepare(struct device *dev, pm_message_t state)
 	if (callback)
 		ret = callback(dev);
 
+unlock:
 	device_unlock(dev);
 
 	if (ret < 0) {
@@ -1769,3 +1733,30 @@ void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
 	device_pm_unlock();
 }
 EXPORT_SYMBOL_GPL(dpm_for_each_dev);
+
+static bool pm_ops_is_empty(const struct dev_pm_ops *ops)
+{
+	if (!ops)
+		return true;
+
+	return !ops->prepare &&
+	       !ops->suspend &&
+	       !ops->suspend_late &&
+	       !ops->suspend_noirq &&
+	       !ops->resume_noirq &&
+	       !ops->resume_early &&
+	       !ops->resume &&
+	       !ops->complete;
+}
+
+void device_pm_check_callbacks(struct device *dev)
+{
+	spin_lock_irq(&dev->power.lock);
+	dev->power.no_pm_callbacks =
+		(!dev->bus || pm_ops_is_empty(dev->bus->pm)) &&
+		(!dev->class || pm_ops_is_empty(dev->class->pm)) &&
+		(!dev->type || pm_ops_is_empty(dev->type->pm)) &&
+		(!dev->pm_domain || pm_ops_is_empty(&dev->pm_domain->ops)) &&
+		(!dev->driver || pm_ops_is_empty(dev->driver->pm));
+	spin_unlock_irq(&dev->power.lock);
+}