Input: serio - do not touch bus's rwsem

The subsystem rwsem is not used by the driver core at all, so there is
no point in trying to access it.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 15 insertions, 26 deletions

diff --git a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c
index a15e531ec755..5895202b972c 100644
--- a/drivers/input/serio/serio.c
+++ b/drivers/input/serio/serio.c
@@ -115,18 +115,18 @@ static int serio_match_port(const struct serio_device_id *ids, struct serio *ser
  * Basic serio -> driver core mappings
  */
 
-static void serio_bind_driver(struct serio *serio, struct serio_driver *drv)
+static int serio_bind_driver(struct serio *serio, struct serio_driver *drv)
 {
         int error;
 
-        down_write(&serio_bus.subsys.rwsem);
-
         if (serio_match_port(drv->id_table, serio)) {
+
                 serio->dev.driver = &drv->driver;
                 if (serio_connect_driver(serio, drv)) {
                         serio->dev.driver = NULL;
-                        goto out;
+                        return -ENODEV;
                 }
+
                 error = device_bind_driver(&serio->dev);
                 if (error) {
                         printk(KERN_WARNING
@@ -136,31 +136,21 @@ static void serio_bind_driver(struct serio *serio, struct serio_driver *drv)
                                 drv->description, error);
                         serio_disconnect_driver(serio);
                         serio->dev.driver = NULL;
-                        goto out;
+                        return error;
                 }
         }
- out:
-        up_write(&serio_bus.subsys.rwsem);
-}
-
-static void serio_release_driver(struct serio *serio)
-{
-        down_write(&serio_bus.subsys.rwsem);
-        device_release_driver(&serio->dev);
-        up_write(&serio_bus.subsys.rwsem);
+        return 0;
 }
 
 static void serio_find_driver(struct serio *serio)
 {
         int error;
 
-        down_write(&serio_bus.subsys.rwsem);
         error = device_attach(&serio->dev);
         if (error < 0)
                 printk(KERN_WARNING
                         "serio: device_attach() failed for %s (%s), error: %d\n",
                         serio->phys, serio->name, error);
-        up_write(&serio_bus.subsys.rwsem);
 }
 
 
@@ -470,13 +460,12 @@ static ssize_t serio_rebind_driver(struct device *dev, struct device_attribute *
 {
         struct serio *serio = to_serio_port(dev);
         struct device_driver *drv;
-        int retval;
+        int error;
 
-        retval = mutex_lock_interruptible(&serio_mutex);
-        if (retval)
-                return retval;
+        error = mutex_lock_interruptible(&serio_mutex);
+        if (error)
+                return error;
 
-        retval = count;
         if (!strncmp(buf, "none", count)) {
                 serio_disconnect_port(serio);
         } else if (!strncmp(buf, "reconnect", count)) {
@@ -486,15 +475,15 @@ static ssize_t serio_rebind_driver(struct device *dev, struct device_attribute *
                 serio_find_driver(serio);
         } else if ((drv = driver_find(buf, &serio_bus)) != NULL) {
                 serio_disconnect_port(serio);
-                serio_bind_driver(serio, to_serio_driver(drv));
+                error = serio_bind_driver(serio, to_serio_driver(drv));
                 put_driver(drv);
         } else {
-                retval = -EINVAL;
+                error = -EINVAL;
         }
 
         mutex_unlock(&serio_mutex);
 
-        return retval;
+        return error ? error : count;
 }
 
 static ssize_t serio_show_bind_mode(struct device *dev, struct device_attribute *attr, char *buf)
@@ -665,7 +654,7 @@ static void serio_disconnect_port(struct serio *serio)
                 do {
                         parent = s->parent;
 
-                        serio_release_driver(s);
+                        device_release_driver(&s->dev);
                         serio_destroy_port(s);
                 } while ((s = parent) != serio);
         }
@@ -673,7 +662,7 @@ static void serio_disconnect_port(struct serio *serio)
         /*
          * Ok, no children left, now disconnect this port
          */
-        serio_release_driver(serio);
+        device_release_driver(&serio->dev);
 }
 
 void serio_rescan(struct serio *serio)