Input: synaptics - fix touchpad not working after S2R on Vostro V13
Synaptics touchpads on several Dell laptops, particularly Vostro V13
systems, may not respond properly to PS/2 commands and queries immediately
after resuming from suspend to RAM. This leads to unresponsive touchpad
after suspend/resume cycle.
Adding a 1-second delay after resetting the device allows touchpad to
finish initializing (calibrating?) and start reacting properly.
Reported-by: Daniel Manrique <daniel.manrique@canonical.com>
Tested-by: Daniel Manrique <daniel.manrique@canonical.com>
Cc: stable@kernel.org
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c
index c080b82..a6dcd18 100644
--- a/drivers/input/mouse/synaptics.c
+++ b/drivers/input/mouse/synaptics.c
@@ -24,6 +24,7 @@
*/
#include <linux/module.h>
+#include <linux/delay.h>
#include <linux/dmi.h>
#include <linux/input/mt.h>
#include <linux/serio.h>
@@ -1220,6 +1221,16 @@
do {
psmouse_reset(psmouse);
+ if (retry) {
+ /*
+ * On some boxes, right after resuming, the touchpad
+ * needs some time to finish initializing (I assume
+ * it needs time to calibrate) and start responding
+ * to Synaptics-specific queries, so let's wait a
+ * bit.
+ */
+ ssleep(1);
+ }
error = synaptics_detect(psmouse, 0);
} while (error && ++retry < 3);