2 files changed, 116 insertions, 34 deletions

diff --git a/drivers/base/power/resume.c b/drivers/base/power/resume.c
index 826093ef4c7..48e3d49d7b6 100644
--- a/drivers/base/power/resume.c
+++ b/drivers/base/power/resume.c
@@ -38,13 +38,35 @@ int resume_device(struct device * dev)
 		dev_dbg(dev,"resuming\n");
 		error = dev->bus->resume(dev);
 	}
+	if (dev->class && dev->class->resume) {
+		dev_dbg(dev,"class resume\n");
+		error = dev->class->resume(dev);
+	}
 	up(&dev->sem);
 	TRACE_RESUME(error);
 	return error;
 }
 
 
+static int resume_device_early(struct device * dev)
+{
+	int error = 0;
 
+	TRACE_DEVICE(dev);
+	TRACE_RESUME(0);
+	if (dev->bus && dev->bus->resume_early) {
+		dev_dbg(dev,"EARLY resume\n");
+		error = dev->bus->resume_early(dev);
+	}
+	TRACE_RESUME(error);
+	return error;
+}
+
+/*
+ * Resume the devices that have either not gone through
+ * the late suspend, or that did go through it but also
+ * went through the early resume
+ */
 void dpm_resume(void)
 {
 	down(&dpm_list_sem);
@@ -99,10 +121,8 @@ void dpm_power_up(void)
 		struct list_head * entry = dpm_off_irq.next;
 		struct device * dev = to_device(entry);
 
-		get_device(dev);
-		list_move_tail(entry, &dpm_active);
-		resume_device(dev);
-		put_device(dev);
+		list_move_tail(entry, &dpm_off);
+		resume_device_early(dev);
 	}
 }
 
diff --git a/drivers/base/power/suspend.c b/drivers/base/power/suspend.c
index 69509e02f70..10e8032aee1 100644
--- a/drivers/base/power/suspend.c
+++ b/drivers/base/power/suspend.c
@@ -65,7 +65,19 @@ int suspend_device(struct device * dev, pm_message_t state)
 
 	dev->power.prev_state = dev->power.power_state;
 
-	if (dev->bus && dev->bus->suspend && !dev->power.power_state.event) {
+	if (dev->class && dev->class->suspend && !dev->power.power_state.event) {
+		dev_dbg(dev, "class %s%s\n",
+			suspend_verb(state.event),
+			((state.event == PM_EVENT_SUSPEND)
+					&& device_may_wakeup(dev))
+				? ", may wakeup"
+				: ""
+			);
+		error = dev->class->suspend(dev, state);
+		suspend_report_result(dev->class->suspend, error);
+	}
+
+	if (!error && dev->bus && dev->bus->suspend && !dev->power.power_state.event) {
 		dev_dbg(dev, "%s%s\n",
 			suspend_verb(state.event),
 			((state.event == PM_EVENT_SUSPEND)
@@ -81,15 +93,74 @@ int suspend_device(struct device * dev, pm_message_t state)
 }
 
 
+/*
+ * This is called with interrupts off, only a single CPU
+ * running. We can't do down() on a semaphore (and we don't
+ * need the protection)
+ */
+static int suspend_device_late(struct device *dev, pm_message_t state)
+{
+	int error = 0;
+
+	if (dev->power.power_state.event) {
+		dev_dbg(dev, "PM: suspend_late %d-->%d\n",
+			dev->power.power_state.event, state.event);
+	}
+
+	if (dev->bus && dev->bus->suspend_late && !dev->power.power_state.event) {
+		dev_dbg(dev, "LATE %s%s\n",
+			suspend_verb(state.event),
+			((state.event == PM_EVENT_SUSPEND)
+					&& device_may_wakeup(dev))
+				? ", may wakeup"
+				: ""
+			);
+		error = dev->bus->suspend_late(dev, state);
+		suspend_report_result(dev->bus->suspend_late, error);
+	}
+	return error;
+}
+
+/**
+ *	device_prepare_suspend - save state and prepare to suspend
+ *
+ *	NOTE! Devices cannot detach at this point - not only do we
+ *	hold the device list semaphores over the whole prepare, but
+ *	the whole point is to do non-invasive preparatory work, not
+ *	the actual suspend.
+ */
+int device_prepare_suspend(pm_message_t state)
+{
+	int error = 0;
+	struct device * dev;
+
+	down(&dpm_sem);
+	down(&dpm_list_sem);
+	list_for_each_entry_reverse(dev, &dpm_active, power.entry) {
+		if (!dev->bus || !dev->bus->suspend_prepare)
+			continue;
+		error = dev->bus->suspend_prepare(dev, state);
+		if (error)
+			break;
+	}
+	up(&dpm_list_sem);
+	up(&dpm_sem);
+	return error;
+}
+
 /**
  *	device_suspend - Save state and stop all devices in system.
  *	@state:		Power state to put each device in.
  *
  *	Walk the dpm_active list, call ->suspend() for each device, and move
- *	it to dpm_off.
- *	Check the return value for each. If it returns 0, then we move the
- *	the device to the dpm_off list. If it returns -EAGAIN, we move it to
- *	the dpm_off_irq list. If we get a different error, try and back out.
+ *	it to the dpm_off list.
+ *
+ *	(For historical reasons, if it returns -EAGAIN, that used to mean
+ *	that the device would be called again with interrupts disabled.
+ *	These days, we use the "suspend_late()" callback for that, so we
+ *	print a warning and consider it an error).
+ *
+ *	If we get a different error, try and back out.
  *
  *	If we hit a failure with any of the devices, call device_resume()
  *	above to bring the suspended devices back to life.
@@ -115,39 +186,27 @@ int device_suspend(pm_message_t state)
 
 		/* Check if the device got removed */
 		if (!list_empty(&dev->power.entry)) {
-			/* Move it to the dpm_off or dpm_off_irq list */
+			/* Move it to the dpm_off list */
 			if (!error)
 				list_move(&dev->power.entry, &dpm_off);
-			else if (error == -EAGAIN) {
-				list_move(&dev->power.entry, &dpm_off_irq);
-				error = 0;
-			}
 		}
 		if (error)
 			printk(KERN_ERR "Could not suspend device %s: "
-				"error %d\n", kobject_name(&dev->kobj), error);
+				"error %d%s\n",
+				kobject_name(&dev->kobj), error,
+				error == -EAGAIN ? " (please convert to suspend_late)" : "");
 		put_device(dev);
 	}
 	up(&dpm_list_sem);
-	if (error) {
-		/* we failed... before resuming, bring back devices from
-		 * dpm_off_irq list back to main dpm_off list, we do want
-		 * to call resume() on them, in case they partially suspended
-		 * despite returning -EAGAIN
-		 */
-		while (!list_empty(&dpm_off_irq)) {
-			struct list_head * entry = dpm_off_irq.next;
-			list_move(entry, &dpm_off);
-		}
+	if (error)
 		dpm_resume();
-	}
+
 	up(&dpm_sem);
 	return error;
 }
 
 EXPORT_SYMBOL_GPL(device_suspend);
 
-
 /**
  *	device_power_down - Shut down special devices.
  *	@state:		Power state to enter.
@@ -162,14 +221,17 @@ int device_power_down(pm_message_t state)
 	int error = 0;
 	struct device * dev;
 
-	list_for_each_entry_reverse(dev, &dpm_off_irq, power.entry) {
-		if ((error = suspend_device(dev, state)))
-			break;
+	while (!list_empty(&dpm_off)) {
+		struct list_head * entry = dpm_off.prev;
+
+		dev = to_device(entry);
+		error = suspend_device_late(dev, state);
+		if (error)
+			goto Error;
+		list_move(&dev->power.entry, &dpm_off_irq);
 	}
-	if (error)
-		goto Error;
-	if ((error = sysdev_suspend(state)))
-		goto Error;
+
+	error = sysdev_suspend(state);
  Done:
 	return error;
  Error: