From: Jiri Slaby <jsl...@suse.cz>
commit 97293de977365fe672daec2523e66ef457104921 upstream.
* allow NULL consw->con_scrolldelta (some consoles define an empty
hook)
* => remove empty hooks now
* return value of consw->con_scrolldelta is never checked => make the
function void
* document consw->con_scrolldelta a bit
Signed-off-by: Jiri Slaby <jsl...@suse.cz>
Cc: Thomas Winischhofer <tho...@winischhofer.net>
Cc: linux-...@vger.kernel.org
Cc: Jean-Christophe Plagniol-Villard <plagn...@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkei...@ti.com>
Cc: "James E.J. Bottomley" <j...@parisc-linux.org>
Cc: Helge Deller <del...@gmx.de>
Cc: linux-fb...@vger.kernel.org
Cc: linux-par...@vger.kernel.org
Cc: Ajay Kaher <aka...@vmware.com>
[ for 4.4.y backport, only do the first change above, to prevent
.con_scrolldelta from being called if not present - gregkh]
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
drivers/tty/vt/vt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -2484,7 +2484,7 @@ static void console_callback(struct work
if (scrollback_delta) {
struct vc_data *vc = vc_cons[fg_console].d;
clear_selection();
- if (vc->vc_mode == KD_TEXT)
+ if (vc->vc_mode == KD_TEXT && vc->vc_sw->con_scrolldelta)
vc->vc_sw->con_scrolldelta(vc, scrollback_delta);
scrollback_delta = 0;
}
