diff options
| -rw-r--r-- | drivers/tty/n_gsm.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 39359274096d..9a3d7db33394 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -2859,11 +2859,24 @@ static ssize_t gsmld_read(struct tty_struct *tty, struct file *file, static ssize_t gsmld_write(struct tty_struct *tty, struct file *file, const unsigned char *buf, size_t nr) { - int space = tty_write_room(tty); + struct gsm_mux *gsm = tty->disc_data; + unsigned long flags; + int space; + int ret; + + if (!gsm) + return -ENODEV; + + ret = -ENOBUFS; + spin_lock_irqsave(&gsm->tx_lock, flags); + space = tty_write_room(tty); if (space >= nr) - return tty->ops->write(tty, buf, nr); - set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); - return -ENOBUFS; + ret = tty->ops->write(tty, buf, nr); + else + set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + spin_unlock_irqrestore(&gsm->tx_lock, flags); + + return ret; } /** |