ACPI: dock: use mutex instead of spinlock

http://bugzilla.kernel.org/show_bug.cgi?id=7303

Use a mutex instead of a spinlock for locking the
hotplug list because we need to call into the ACPI
subsystem which might sleep.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 8 insertions, 8 deletions

diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c
index 578b99b71d9c..c7df2a1ea9d7 100644
--- a/drivers/acpi/dock.c
+++ b/drivers/acpi/dock.c
@@ -44,7 +44,7 @@ struct dock_station {
         unsigned long last_dock_time;
         u32 flags;
         spinlock_t dd_lock;
-        spinlock_t hp_lock;
+        struct mutex hp_lock;
         struct list_head dependent_devices;
         struct list_head hotplug_devices;
 };
@@ -114,9 +114,9 @@ static void
 dock_add_hotplug_device(struct dock_station *ds,
                         struct dock_dependent_device *dd)
 {
-        spin_lock(&ds->hp_lock);
+        mutex_lock(&ds->hp_lock);
         list_add_tail(&dd->hotplug_list, &ds->hotplug_devices);
-        spin_unlock(&ds->hp_lock);
+        mutex_unlock(&ds->hp_lock);
 }
 
 /**
@@ -130,9 +130,9 @@ static void
 dock_del_hotplug_device(struct dock_station *ds,
                         struct dock_dependent_device *dd)
 {
-        spin_lock(&ds->hp_lock);
+        mutex_lock(&ds->hp_lock);
         list_del(&dd->hotplug_list);
-        spin_unlock(&ds->hp_lock);
+        mutex_unlock(&ds->hp_lock);
 }
 
 /**
@@ -295,7 +295,7 @@ static void hotplug_dock_devices(struct dock_station *ds, u32 event)
 {
         struct dock_dependent_device *dd;
 
-        spin_lock(&ds->hp_lock);
+        mutex_lock(&ds->hp_lock);
 
         /*
          * First call driver specific hotplug functions
@@ -317,7 +317,7 @@ static void hotplug_dock_devices(struct dock_station *ds, u32 event)
                 else
                         dock_create_acpi_device(dd->handle);
         }
-        spin_unlock(&ds->hp_lock);
+        mutex_unlock(&ds->hp_lock);
 }
 
 static void dock_event(struct dock_station *ds, u32 event, int num)
@@ -625,7 +625,7 @@ static int dock_add(acpi_handle handle)
         INIT_LIST_HEAD(&dock_station->dependent_devices);
         INIT_LIST_HEAD(&dock_station->hotplug_devices);
         spin_lock_init(&dock_station->dd_lock);
-        spin_lock_init(&dock_station->hp_lock);
+        mutex_init(&dock_station->hp_lock);
         ATOMIC_INIT_NOTIFIER_HEAD(&dock_notifier_list);
 
         /* Find dependent devices */