diff options
Diffstat (limited to 'drivers/firewire/nosy.c')
| -rw-r--r-- | drivers/firewire/nosy.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/firewire/nosy.c b/drivers/firewire/nosy.c index 180f0a96528c..646dca0a8d73 100644 --- a/drivers/firewire/nosy.c +++ b/drivers/firewire/nosy.c @@ -359,6 +359,7 @@ nosy_ioctl(struct file *file, unsigned int cmd, unsigned long arg) struct client *client = file->private_data; spinlock_t *client_list_lock = &client->lynx->client_list_lock; struct nosy_stats stats; + int ret; switch (cmd) { case NOSY_IOC_GET_STATS: @@ -373,11 +374,15 @@ nosy_ioctl(struct file *file, unsigned int cmd, unsigned long arg) return 0; case NOSY_IOC_START: + ret = -EBUSY; spin_lock_irq(client_list_lock); - list_add_tail(&client->link, &client->lynx->client_list); + if (list_empty(&client->link)) { + list_add_tail(&client->link, &client->lynx->client_list); + ret = 0; + } spin_unlock_irq(client_list_lock); - return 0; + return ret; case NOSY_IOC_STOP: spin_lock_irq(client_list_lock); |