diff options
Diffstat (limited to 'drivers/accessibility/speakup/spk_ttyio.c')
| -rw-r--r-- | drivers/accessibility/speakup/spk_ttyio.c | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/drivers/accessibility/speakup/spk_ttyio.c b/drivers/accessibility/speakup/spk_ttyio.c index a831ff64f8ba..669392f31d4e 100644 --- a/drivers/accessibility/speakup/spk_ttyio.c +++ b/drivers/accessibility/speakup/spk_ttyio.c @@ -49,15 +49,25 @@ static int spk_ttyio_ldisc_open(struct tty_struct *tty) if (!tty->ops->write) return -EOPNOTSUPP; + + mutex_lock(&speakup_tty_mutex); + if (speakup_tty) { + mutex_unlock(&speakup_tty_mutex); + return -EBUSY; + } speakup_tty = tty; ldisc_data = kmalloc(sizeof(*ldisc_data), GFP_KERNEL); - if (!ldisc_data) + if (!ldisc_data) { + speakup_tty = NULL; + mutex_unlock(&speakup_tty_mutex); return -ENOMEM; + } init_completion(&ldisc_data->completion); ldisc_data->buf_free = true; speakup_tty->disc_data = ldisc_data; + mutex_unlock(&speakup_tty_mutex); return 0; } @@ -298,11 +308,13 @@ static unsigned char ttyio_in(int timeout) struct spk_ldisc_data *ldisc_data = speakup_tty->disc_data; char rv; - if (wait_for_completion_timeout(&ldisc_data->completion, + if (!timeout) { + if (!try_wait_for_completion(&ldisc_data->completion)) + return 0xff; + } else if (wait_for_completion_timeout(&ldisc_data->completion, usecs_to_jiffies(timeout)) == 0) { - if (timeout) - pr_warn("spk_ttyio: timeout (%d) while waiting for input\n", - timeout); + pr_warn("spk_ttyio: timeout (%d) while waiting for input\n", + timeout); return 0xff; } |