[PATCH] chardev: GPIO for SCx200 & PC-8736x: dispatch via vtable

[firefly-linux-kernel-4.4.55.git] / drivers / char / tty_io.c

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 8b2a5996986819b62eccb4ffdb436d1d3903521a..bd74e82d8a72a443b8ca4579898e3dcf11e876f3 100644 (file)
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -2621,10 +2621,9 @@ int tty_ioctl(struct inode * inode, struct file * file,
                        tty->driver->break_ctl(tty, 0);
                        return 0;
                case TCSBRK:   /* SVID version: non-zero arg --> no break */
-                       /*
-                        * XXX is the above comment correct, or the
-                        * code below correct?  Is this ioctl used at
-                        * all by anyone?
+                       /* non-zero arg means wait for all output data
+                        * to be sent (performed above) but don't send break.
+                        * This is used by the tcdrain() termios function.
                         */
                        if (!arg)
                                return send_break(tty, 250);