diff options
| -rw-r--r-- | drivers/input/input.c | 33 | ||||
| -rw-r--r-- | include/linux/input.h | 4 |
2 files changed, 32 insertions, 5 deletions
diff --git a/drivers/input/input.c b/drivers/input/input.c index 3385dd03abfc..1885f369e3e2 100644 --- a/drivers/input/input.c +++ b/drivers/input/input.c @@ -219,10 +219,24 @@ void input_release_device(struct input_handle *handle) int input_open_device(struct input_handle *handle) { + struct input_dev *dev = handle->dev; + int err; + + err = down_interruptible(&dev->sem); + if (err) + return err; + handle->open++; - if (handle->dev->open) - return handle->dev->open(handle->dev); - return 0; + + if (!dev->users++ && dev->open) + err = dev->open(dev); + + if (err) + handle->open--; + + up(&dev->sem); + + return err; } int input_flush_device(struct input_handle* handle, struct file* file) @@ -235,10 +249,17 @@ int input_flush_device(struct input_handle* handle, struct file* file) void input_close_device(struct input_handle *handle) { + struct input_dev *dev = handle->dev; + input_release_device(handle); - if (handle->dev->close) - handle->dev->close(handle->dev); + + down(&dev->sem); + + if (!--dev->users && dev->close) + dev->close(dev); handle->open--; + + up(&dev->sem); } static void input_link_handle(struct input_handle *handle) @@ -415,6 +436,8 @@ void input_register_device(struct input_dev *dev) set_bit(EV_SYN, dev->evbit); + init_MUTEX(&dev->sem); + /* * If delay and period are pre-set by the driver, then autorepeating * is handled by the driver itself and we don't do it in input.c. diff --git a/include/linux/input.h b/include/linux/input.h index 72731d7d189e..43e8ecec602b 100644 --- a/include/linux/input.h +++ b/include/linux/input.h @@ -859,6 +859,10 @@ struct input_dev { int (*erase_effect)(struct input_dev *dev, int effect_id); struct input_handle *grab; + + struct semaphore sem; /* serializes open and close operations */ + unsigned int users; + struct device *dev; struct list_head h_list; |