From: Shawn Nematbakhsh <shawnn@google.com>
Date: Thu, 25 Apr 2013 21:30:04 +0000 (-0700)
Subject: CHROMIUM: input: mouse - Fix trackpoint re-probe on resume.
X-Git-Url: http://git.cascardo.eti.br/?a=commitdiff_plain;h=f097bc2d8174d4f5161d1e4741a0a5bd5f63d1a3;hp=3631d956e44fb78c5a6516180ce76a5a49904851;p=cascardo%2Flinux.git

CHROMIUM: input: mouse - Fix trackpoint re-probe on resume.

During suspend, power may be cut to the trackpoint. If so, the
trackpoint will automatically begin its power-on diagnostics upon being
re-powered. If trackpoint_reconnect is called before the diagnostics
complete, the probe ID command will be lost, and reconnect will fail.
This will lead to re-probe, which takes several seconds on Stout due to
the trackpoint / trackpad pass-through design.

The fix here is to make a second attempt if the initial commands on
reconnect fail, which should give the trackpoint enough time to come out
of power-on diagnostics.

TEST=suspend/resume test for 3000 iterations without re-enumeration.
BUG=chromium:220389

Change-Id: I1ff8d3accdde86184864915d540b870ed33feee4
Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/49228
Reviewed-by: Chung-yih Wang <cywang@chromium.org>
---

diff --git a/drivers/input/mouse/trackpoint.c b/drivers/input/mouse/trackpoint.c
index 4c16c5b335fb..62ad2564707b 100644
--- a/drivers/input/mouse/trackpoint.c
+++ b/drivers/input/mouse/trackpoint.c
@@ -334,8 +334,14 @@ static void trackpoint_disconnect(struct psmouse *psmouse)
 static int trackpoint_reconnect(struct psmouse *psmouse)
 {
 	int reset_fail;
+	int ret;
+	int tries = 2;
 
-	if (trackpoint_start_protocol(psmouse, NULL))
+	do {
+		ret = trackpoint_start_protocol(psmouse, NULL);
+	} while (ret != 0 && --tries > 0);
+
+	if (ret != 0)
 		return -1;
 
 	reset_fail = trackpoint_power_on_reset(&psmouse->ps2dev);