tty: Fix comments for tty_ldisc_get()

tty_ldisc_get() returns ERR_PTR() values if unsuccessful, not NULL;
fix function header documentation.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 10 insertions, 3 deletions

diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index b2e8210639dd..4008f5f65345 100644
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -140,9 +140,16 @@ static void put_ldops(struct tty_ldisc_ops *ldops)
  *      @disc: ldisc number
  *
  *      Takes a reference to a line discipline. Deals with refcounts and
- *      module locking counts. Returns NULL if the discipline is not available.
- *      Returns a pointer to the discipline and bumps the ref count if it is
- *      available
+ *      module locking counts.
+ *
+ *      Returns: -EINVAL if the discipline index is not [N_TTY..NR_LDISCS] or
+ *                       if the discipline is not registered
+ *               -EAGAIN if request_module() failed to load or register the
+ *                       the discipline
+ *               -ENOMEM if allocation failure
+ *
+ *               Otherwise, returns a pointer to the discipline and bumps the
+ *               ref count
  *
  *      Locking:
  *              takes tty_ldiscs_lock to guard against ldisc races