FAQ Search Today's Posts Mark Forums Read
» Video Reviews

» Linux Archive

Linux-archive is a website aiming to archive linux email lists and to make them easily accessible for linux users/developers.


» Sponsor

» Partners

» Sponsor

Go Back   Linux Archive > Ubuntu > Ubuntu Kernel Team

 
 
LinkBack Thread Tools
 
Old 10-04-2012, 02:07 PM
Tim Gardner
 
Default ACK: UBUNTU: SAUCE: input: fix weird issue of synaptics psmouse sync lost after resume

On 10/03/2012 04:20 PM, James M Leddy wrote:
> 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.
>
> BugLink: https://bugs.launchpad.net/bugs/717970
> http://thread.gmane.org/gmane.linux.kernel.input/25599
> Signed-off-by: James M Leddy <james.leddy@canonical.com>
> ---
> drivers/input/mouse/synaptics.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c
> index ab6d145..44690b0 100644
> --- a/drivers/input/mouse/synaptics.c
> +++ b/drivers/input/mouse/synaptics.c
> @@ -1324,6 +1324,7 @@ 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;
>
> @@ -1339,6 +1340,7 @@ 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);
>
>

Seems harmless.
--
Tim Gardner tim.gardner@canonical.com

--
kernel-team mailing list
kernel-team@lists.ubuntu.com
https://lists.ubuntu.com/mailman/listinfo/kernel-team
 
Old 10-04-2012, 02:19 PM
Seth Forshee
 
Default ACK: UBUNTU: SAUCE: input: fix weird issue of synaptics psmouse sync lost after resume

--
kernel-team mailing list
kernel-team@lists.ubuntu.com
https://lists.ubuntu.com/mailman/listinfo/kernel-team
 

Thread Tools




All times are GMT. The time now is 02:06 PM.

VBulletin, Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.
Copyright 2007 - 2008, www.linux-archive.org