diff options
| -rw-r--r-- | drivers/staging/greybus/raw.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/drivers/staging/greybus/raw.c b/drivers/staging/greybus/raw.c index 47a984554681..459aed0f1240 100644 --- a/drivers/staging/greybus/raw.c +++ b/drivers/staging/greybus/raw.c @@ -21,6 +21,8 @@ struct gb_raw { struct list_head list; int list_data; struct mutex list_lock; + struct rw_semaphore disconnect_lock; + bool disconnected; struct cdev cdev; struct device dev; }; @@ -200,6 +202,7 @@ static int gb_raw_probe(struct gb_bundle *bundle, INIT_LIST_HEAD(&raw->list); mutex_init(&raw->list_lock); + init_rwsem(&raw->disconnect_lock); raw->connection = connection; greybus_set_drvdata(bundle, raw); @@ -235,6 +238,11 @@ static void gb_raw_disconnect(struct gb_bundle *bundle) struct raw_data *temp; cdev_device_del(&raw->cdev, &raw->dev); + + down_write(&raw->disconnect_lock); + raw->disconnected = true; + up_write(&raw->disconnect_lock); + gb_connection_disable(connection); gb_connection_destroy(connection); @@ -277,11 +285,22 @@ static ssize_t raw_write(struct file *file, const char __user *buf, if (count > MAX_PACKET_SIZE) return -E2BIG; + down_read(&raw->disconnect_lock); + + if (raw->disconnected) { + retval = -ENODEV; + goto exit; + } + retval = gb_raw_send(raw, count, buf); if (retval) - return retval; + goto exit; - return count; + retval = count; +exit: + up_read(&raw->disconnect_lock); + + return retval; } static ssize_t raw_read(struct file *file, char __user *buf, size_t count, |