tty: Remove chars_in_buffer() line discipline method
The chars_in_buffer() line discipline method serves no functional
purpose, other than as a (dubious) debugging aid for mostly bit-rotting
drivers. Despite being documented as an optional method, every caller
is unconditionally executed (although conditionally compiled).
Furthermore, direct tty->ldisc access without an ldisc ref is unsafe.
Lastly, N_TTY's chars_in_buffer() has warned of removal since 3.12.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/rocket.c b/drivers/tty/rocket.c
index 802eac7..f624b93 100644
--- a/drivers/tty/rocket.c
+++ b/drivers/tty/rocket.c
@@ -1360,8 +1360,7 @@
struct r_port *info = tty->driver_data;
#ifdef ROCKET_DEBUG_THROTTLE
- printk(KERN_INFO "throttle %s: %d....\n", tty->name,
- tty->ldisc.chars_in_buffer(tty));
+ printk(KERN_INFO "throttle %s ....\n", tty->name);
#endif
if (rocket_paranoia_check(info, "rp_throttle"))
@@ -1377,8 +1376,7 @@
{
struct r_port *info = tty->driver_data;
#ifdef ROCKET_DEBUG_THROTTLE
- printk(KERN_INFO "unthrottle %s: %d....\n", tty->name,
- tty->ldisc.chars_in_buffer(tty));
+ printk(KERN_INFO "unthrottle %s ....\n", tty->name);
#endif
if (rocket_paranoia_check(info, "rp_unthrottle"))