Power Management: use mutexes instead of semaphores
The Power Management code uses semaphores as mutexes. Use the mutex API
instead of the (binary) semaphores.
Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/base/power/suspend.c b/drivers/base/power/suspend.c
index 42d2b86..9d6701c 100644
--- a/drivers/base/power/suspend.c
+++ b/drivers/base/power/suspend.c
@@ -108,7 +108,7 @@
/*
* This is called with interrupts off, only a single CPU
- * running. We can't do down() on a semaphore (and we don't
+ * running. We can't acquire a mutex or semaphore (and we don't
* need the protection)
*/
static int suspend_device_late(struct device *dev, pm_message_t state)
@@ -153,18 +153,18 @@
int error = 0;
might_sleep();
- down(&dpm_sem);
- down(&dpm_list_sem);
+ mutex_lock(&dpm_mtx);
+ mutex_lock(&dpm_list_mtx);
while (!list_empty(&dpm_active) && error == 0) {
struct list_head * entry = dpm_active.prev;
struct device * dev = to_device(entry);
get_device(dev);
- up(&dpm_list_sem);
+ mutex_unlock(&dpm_list_mtx);
error = suspend_device(dev, state);
- down(&dpm_list_sem);
+ mutex_lock(&dpm_list_mtx);
/* Check if the device got removed */
if (!list_empty(&dev->power.entry)) {
@@ -179,11 +179,11 @@
error == -EAGAIN ? " (please convert to suspend_late)" : "");
put_device(dev);
}
- up(&dpm_list_sem);
+ mutex_unlock(&dpm_list_mtx);
if (error)
dpm_resume();
- up(&dpm_sem);
+ mutex_unlock(&dpm_mtx);
return error;
}