xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

tty: Remove chars_in_buffer() line discipline method

Browse Source 
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>
This commit is contained in:
Peter Hurley
2016-01-10 22:40:54 -08:00
committed by Greg Kroah-Hartman
parent 582e20a03b
commit fdfb719e93
8 changed files with 13 additions and 68 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
Documentation/serial/tty.txt
View File

@@ -72,9 +72,6 @@ flush_buffer() - (optional) May be called at any point between
open and close, and instructs the line discipline
to empty its input buffer.
chars_in_buffer() - (optional) Report the number of bytes in the input
buffer.
set_termios() - (optional) Called on termios structure changes.
The caller passes the old termios data and the
current data is in the tty. Called under the