4 files changed, 77 insertions, 36 deletions

diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 15e6a8f951f1..0d2e101e4f15 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -30,23 +30,6 @@ LIST_HEAD(dpm_off_irq);
 DECLARE_MUTEX(dpm_sem);
 DECLARE_MUTEX(dpm_list_sem);
 
-/*
- * PM Reference Counting.
- */
-
-static inline void device_pm_hold(struct device * dev)
-{
-        if (dev)
-                atomic_inc(&dev->power.pm_users);
-}
-
-static inline void device_pm_release(struct device * dev)
-{
-        if (dev)
-                atomic_dec(&dev->power.pm_users);
-}
-
-
 /**
  *      device_pm_set_parent - Specify power dependency.
  *      @dev:           Device who needs power.
@@ -62,10 +45,8 @@ static inline void device_pm_release(struct device * dev)
 
 void device_pm_set_parent(struct device * dev, struct device * parent)
 {
-        struct device * old_parent = dev->power.pm_parent;
-        device_pm_release(old_parent);
-        dev->power.pm_parent = parent;
-        device_pm_hold(parent);
+        put_device(dev->power.pm_parent);
+        dev->power.pm_parent = get_device(parent);
 }
 EXPORT_SYMBOL_GPL(device_pm_set_parent);
 
@@ -75,7 +56,6 @@ int device_pm_add(struct device * dev)
 
         pr_debug("PM: Adding info for %s:%s\n",
                  dev->bus ? dev->bus->name : "No Bus", dev->kobj.name);
-        atomic_set(&dev->power.pm_users, 0);
         down(&dpm_list_sem);
         list_add_tail(&dev->power.entry, &dpm_active);
         device_pm_set_parent(dev, dev->parent);
@@ -91,7 +71,7 @@ void device_pm_remove(struct device * dev)
                  dev->bus ? dev->bus->name : "No Bus", dev->kobj.name);
         down(&dpm_list_sem);
         dpm_sysfs_remove(dev);
-        device_pm_release(dev->power.pm_parent);
+        put_device(dev->power.pm_parent);
         list_del_init(&dev->power.entry);
         up(&dpm_list_sem);
 }
diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h
index 2e700d795cf1..fb3d35a9e101 100644
--- a/drivers/base/power/power.h
+++ b/drivers/base/power/power.h
@@ -67,9 +67,6 @@ extern int suspend_device(struct device *, pm_message_t);
  * runtime.c
  */
 
-extern int dpm_runtime_suspend(struct device *, pm_message_t);
-extern void dpm_runtime_resume(struct device *);
-
 #else /* CONFIG_PM */
 
 
@@ -82,14 +79,4 @@ static inline void device_pm_remove(struct device * dev)
 
 }
 
-static inline int dpm_runtime_suspend(struct device * dev, pm_message_t state)
-{
-        return 0;
-}
-
-static inline void dpm_runtime_resume(struct device * dev)
-{
-
-}
-
 #endif
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index e8f0519f5dfa..adbc3148c039 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -36,6 +36,7 @@ void dpm_runtime_resume(struct device * dev)
         runtime_resume(dev);
         up(&dpm_sem);
 }
+EXPORT_SYMBOL(dpm_runtime_resume);
 
 
 /**
diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
index 8d04fb435c17..89c57875f3e5 100644
--- a/drivers/base/power/sysfs.c
+++ b/drivers/base/power/sysfs.c
@@ -48,8 +48,81 @@ static ssize_t state_store(struct device * dev, struct device_attribute *attr, c
 static DEVICE_ATTR(state, 0644, state_show, state_store);
 
 
+/*
+ *      wakeup - Report/change current wakeup option for device
+ *
+ *      Some devices support "wakeup" events, which are hardware signals
+ *      used to activate devices from suspended or low power states.  Such
+ *      devices have one of three values for the sysfs power/wakeup file:
+ *
+ *       + "enabled\n" to issue the events;
+ *       + "disabled\n" not to do so; or
+ *       + "\n" for temporary or permanent inability to issue wakeup.
+ *
+ *      (For example, unconfigured USB devices can't issue wakeups.)
+ *
+ *      Familiar examples of devices that can issue wakeup events include
+ *      keyboards and mice (both PS2 and USB styles), power buttons, modems,
+ *      "Wake-On-LAN" Ethernet links, GPIO lines, and more.  Some events
+ *      will wake the entire system from a suspend state; others may just
+ *      wake up the device (if the system as a whole is already active).
+ *      Some wakeup events use normal IRQ lines; other use special out
+ *      of band signaling.
+ *
+ *      It is the responsibility of device drivers to enable (or disable)
+ *      wakeup signaling as part of changing device power states, respecting
+ *      the policy choices provided through the driver model.
+ *
+ *      Devices may not be able to generate wakeup events from all power
+ *      states.  Also, the events may be ignored in some configurations;
+ *      for example, they might need help from other devices that aren't
+ *      active, or which may have wakeup disabled.  Some drivers rely on
+ *      wakeup events internally (unless they are disabled), keeping
+ *      their hardware in low power modes whenever they're unused.  This
+ *      saves runtime power, without requiring system-wide sleep states.
+ */
+
+static const char enabled[] = "enabled";
+static const char disabled[] = "disabled";
+
+static ssize_t
+wake_show(struct device * dev, struct device_attribute *attr, char * buf)
+{
+        return sprintf(buf, "%s\n", device_can_wakeup(dev)
+                ? (device_may_wakeup(dev) ? enabled : disabled)
+                : "");
+}
+
+static ssize_t
+wake_store(struct device * dev, struct device_attribute *attr,
+        const char * buf, size_t n)
+{
+        char *cp;
+        int len = n;
+
+        if (!device_can_wakeup(dev))
+                return -EINVAL;
+
+        cp = memchr(buf, '\n', n);
+        if (cp)
+                len = cp - buf;
+        if (len == sizeof enabled - 1
+                        && strncmp(buf, enabled, sizeof enabled - 1) == 0)
+                device_set_wakeup_enable(dev, 1);
+        else if (len == sizeof disabled - 1
+                        && strncmp(buf, disabled, sizeof disabled - 1) == 0)
+                device_set_wakeup_enable(dev, 0);
+        else
+                return -EINVAL;
+        return n;
+}
+
+static DEVICE_ATTR(wakeup, 0644, wake_show, wake_store);
+
+
 static struct attribute * power_attrs[] = {
         &dev_attr_state.attr,
+        &dev_attr_wakeup.attr,
         NULL,
 };
 static struct attribute_group pm_attr_group = {