Commit 368c1e32 authored Dec 16, 2008 by Hendrik Brueckner Committed by Paul Mackerras Dec 21, 2008

hvc_console: Escape magic sysrq key



The ctrl-o (^O) is a common control key used by several applications,
such as vim, but hvc_console uses ^O as the magic-sysrq key.  This
commit allows users to send ^O to applications by pressing ^O twice
in succession.

To implement this, this commit introduces a check if ^O is pressed
again if the sysrq_pressed variable is already set.  In this case,
clear sysrq_pressed state and flip the ^O character to the tty.  (The
old behavior has always set "sysrq_pressed" if ^O has been entered,
and it has not flipped the ^O character to the tty.)

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

parent 532774ec

drivers/char/hvc_console.c

+5 −2

Original line number	Diff line number	Diff line
		@@ -642,7 +642,10 @@ int hvc_poll(struct hvc_struct *hp)
		/* Handle the SysRq Hack */
		/* XXX should support a sequence */
		if (buf[i] == '\x0f') { /* ^O */
		sysrq_pressed = 1;
		/* if ^O is pressed again, reset
		* sysrq_pressed and flip ^O char */
		sysrq_pressed = !sysrq_pressed;
		if (sysrq_pressed)
		continue;
		} else if (sysrq_pressed) {
		handle_sysrq(buf[i], tty);