diff options
author | James M Leddy <james.leddy@canonical.com> | 2012-10-03 18:20:56 -0400 |
---|---|---|
committer | John Rigby <john.rigby@linaro.org> | 2012-11-14 18:19:42 -0700 |
commit | 723dccc0ecde0544ae573aab94a5eb0d1ccf3a0e (patch) | |
tree | 5b0a4c69daf13c5328c924062cd88b21e1b60647 | |
parent | 357c2b052f333c8eba8b6f7b6c9070c65f28633f (diff) |
UBUNTU: SAUCE: input: fix weird issue of synaptics psmouse sync lost after resume
BugLink: http://bugs.launchpad.net/bugs/717970
From: Eric Miao <eric.miao@canonical.com>
This patch has already been sent upstream by Eric. Unfortunately,
after a little back and forth between Eric and Dmitry Torokhov, the
patch did get included, and there is still an open question to Dmitry.
However, this is a known issue on at least 4 systems, and it causes
them to lose their mouse device on suspend. So I was hoping we could
get it in to quantal. Original email follows:
So in summary, the symptom is intermittent key events lost after resume
on some machines with synaptics touchpad (seems this is synaptics _only_),
and key events loss is due to serio port reconnect after psmouse sync lost.
Removing psmouse and inserting it back during the suspend/resume process
is able to work around the issue, so the difference between psmouse_connect()
and psmouse_reconnect() is the key to the root cause of this problem.
After comparing the two different paths, synaptics driver has its own
implementation of synaptics_reconnect(), and the missing psmouse_probe()
seems significant, the patch below added psmouse_probe() to the reconnect
process, and has been verified many times that the issue could not be reliably
reproduced.
There are two PS/2 commands in psmouse_probe():
1. PSMOUSE_CMD_GETID
2. PSMOUSE_CMD_RESET_DIS
The weird thing is, the PSMOUSE_CMD_GETID seems to be significant, and the
PSMOUSE_CMD_RESET_DIS is irrelevant to this issue after trying several times.
Now it's rather difficult to form a sane theory. So this patch is
really for RFC.
Note it does fix a real problem though.
http://thread.gmane.org/gmane.linux.kernel.input/25599
Signed-off-by: James M Leddy <james.leddy@canonical.com>
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
-rw-r--r-- | drivers/input/mouse/synaptics.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c index 48ec7da014d..e8cf85d36ad 100644 --- a/drivers/input/mouse/synaptics.c +++ b/drivers/input/mouse/synaptics.c @@ -1357,6 +1357,7 @@ static int synaptics_reconnect(struct psmouse *psmouse) { struct synaptics_data *priv = psmouse->private; struct synaptics_data old_priv = *priv; + unsigned char param[2]; int retry = 0; int error; @@ -1372,6 +1373,7 @@ static int synaptics_reconnect(struct psmouse *psmouse) */ ssleep(1); } + ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_GETID); error = synaptics_detect(psmouse, 0); } while (error && ++retry < 3); |