Input: serio/gameport - check whether driver core calls succeeded

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 49 insertions, 17 deletions

diff --git a/drivers/input/gameport/gameport.c b/drivers/input/gameport/gameport.c
index 36644bff379d..3f47ae55c6f3 100644
--- a/drivers/input/gameport/gameport.c
+++ b/drivers/input/gameport/gameport.c
@@ -53,6 +53,7 @@ static LIST_HEAD(gameport_list);
 
 static struct bus_type gameport_bus;
 
+static void gameport_add_driver(struct gameport_driver *drv);
 static void gameport_add_port(struct gameport *gameport);
 static void gameport_destroy_port(struct gameport *gameport);
 static void gameport_reconnect_port(struct gameport *gameport);
@@ -211,8 +212,14 @@ static void gameport_release_driver(struct gameport *gameport)
 
 static void gameport_find_driver(struct gameport *gameport)
 {
+        int error;
+
         down_write(&gameport_bus.subsys.rwsem);
-        device_attach(&gameport->dev);
+        error = device_attach(&gameport->dev);
+        if (error < 0)
+                printk(KERN_WARNING
+                        "gameport: device_attach() failed for %s (%s), error: %d\n",
+                        gameport->phys, gameport->name, error);
         up_write(&gameport_bus.subsys.rwsem);
 }
 
@@ -316,7 +323,6 @@ static void gameport_remove_duplicate_events(struct gameport_event *event)
         spin_unlock_irqrestore(&gameport_event_lock, flags);
 }
 
-
 static struct gameport_event *gameport_get_event(void)
 {
         struct gameport_event *event;
@@ -342,7 +348,6 @@ static struct gameport_event *gameport_get_event(void)
 static void gameport_handle_event(void)
 {
         struct gameport_event *event;
-        struct gameport_driver *gameport_drv;
 
         mutex_lock(&gameport_mutex);
 
@@ -369,8 +374,7 @@ static void gameport_handle_event(void)
                                 break;
 
                         case GAMEPORT_REGISTER_DRIVER:
-                                gameport_drv = event->object;
-                                driver_register(&gameport_drv->driver);
+                                gameport_add_driver(event->object);
                                 break;
 
                         default:
@@ -532,6 +536,7 @@ static void gameport_init_port(struct gameport *gameport)
         if (gameport->parent)
                 gameport->dev.parent = &gameport->parent->dev;
 
+        INIT_LIST_HEAD(&gameport->node);
         spin_lock_init(&gameport->timer_lock);
         init_timer(&gameport->poll_timer);
         gameport->poll_timer.function = gameport_run_poll_handler;
@@ -544,6 +549,8 @@ static void gameport_init_port(struct gameport *gameport)
  */
 static void gameport_add_port(struct gameport *gameport)
 {
+        int error;
+
         if (gameport->parent)
                 gameport->parent->child = gameport;
 
@@ -558,8 +565,13 @@ static void gameport_add_port(struct gameport *gameport)
                 printk(KERN_INFO "gameport: %s is %s, speed %dkHz\n",
                         gameport->name, gameport->phys, gameport->speed);
 
-        device_add(&gameport->dev);
-        gameport->registered = 1;
+        error = device_add(&gameport->dev);
+        if (error)
+                printk(KERN_ERR
+                        "gameport: device_add() failed for %s (%s), error: %d\n",
+                        gameport->phys, gameport->name, error);
+        else
+                gameport->registered = 1;
 }
 
 /*
@@ -583,10 +595,11 @@ static void gameport_destroy_port(struct gameport *gameport)
 
         if (gameport->registered) {
                 device_del(&gameport->dev);
-                list_del_init(&gameport->node);
                 gameport->registered = 0;
         }
 
+        list_del_init(&gameport->node);
+
         gameport_remove_pending_events(gameport);
         put_device(&gameport->dev);
 }
@@ -704,11 +717,22 @@ static int gameport_driver_remove(struct device *dev)
 }
 
 static struct bus_type gameport_bus = {
-        .name = "gameport",
-        .probe = gameport_driver_probe,
-        .remove = gameport_driver_remove,
+        .name   = "gameport",
+        .probe  = gameport_driver_probe,
+        .remove = gameport_driver_remove,
 };
 
+static void gameport_add_driver(struct gameport_driver *drv)
+{
+        int error;
+
+        error = driver_register(&drv->driver);
+        if (error)
+                printk(KERN_ERR
+                        "gameport: driver_register() failed for %s, error: %d\n",
+                        drv->driver.name, error);
+}
+
 void __gameport_register_driver(struct gameport_driver *drv, struct module *owner)
 {
         drv->driver.bus = &gameport_bus;
@@ -778,16 +802,24 @@ void gameport_close(struct gameport *gameport)
 
 static int __init gameport_init(void)
 {
-        gameport_task = kthread_run(gameport_thread, NULL, "kgameportd");
-        if (IS_ERR(gameport_task)) {
-                printk(KERN_ERR "gameport: Failed to start kgameportd\n");
-                return PTR_ERR(gameport_task);
-        }
+        int error;
 
         gameport_bus.dev_attrs = gameport_device_attrs;
         gameport_bus.drv_attrs = gameport_driver_attrs;
         gameport_bus.match = gameport_bus_match;
-        bus_register(&gameport_bus);
+        error = bus_register(&gameport_bus);
+        if (error) {
+                printk(KERN_ERR "gameport: failed to register gameport bus, error: %d\n", error);
+                return error;
+        }
+
+        gameport_task = kthread_run(gameport_thread, NULL, "kgameportd");
+        if (IS_ERR(gameport_task)) {
+                bus_unregister(&gameport_bus);
+                error = PTR_ERR(gameport_task);
+                printk(KERN_ERR "gameport: Failed to start kgameportd, error: %d\n", error);
+                return error;
+        }
 
         return 0;
 }