[PATCH] Fix ALPS sync loss

[PATCH] Fix ALPS sync loss

[Dmitry Torokhov]

Hi,

Here is the promised patch. It turns out protocol validation code was
a bit (or rather a byte ;) ) off.

Please let me know if it fixes your touchpad and I believe it would be
nice to have it in 2.6.11.

-- 
Dmitry


===================================================================


ChangeSet@1.2147, 2005-02-08 18:12:06-05:00, dtor_core@ameritech.net
  Input: alps - fix protocol validation rules causing touchpad
         to lose sync if an absolute packet is received after
         a relative packet with negative Y displacement.
  
  Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
  


 alps.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)


===================================================================



diff -Nru a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c
--- a/drivers/input/mouse/alps.c	2005-02-08 18:16:27 -05:00
+++ b/drivers/input/mouse/alps.c	2005-02-08 18:16:27 -05:00
@@ -198,8 +198,8 @@
 		return PSMOUSE_BAD_DATA;
 
 	/* Bytes 2 - 6 should have 0 in the highest bit */
-	if (psmouse->pktcnt > 1 && psmouse->pktcnt <= 6 &&
-	    (psmouse->packet[psmouse->pktcnt] & 0x80))
+	if (psmouse->pktcnt >= 2 && psmouse->pktcnt <= 6 &&
+	    (psmouse->packet[psmouse->pktcnt - 1] & 0x80))
 		return PSMOUSE_BAD_DATA;
 
 	if (psmouse->pktcnt == 6) {

Re: [PATCH] Fix ALPS sync loss

[Vojtech Pavlik]

On Tue, Feb 08, 2005 at 06:40:12PM -0500, Dmitry Torokhov wrote:
> Hi,
> 
> Here is the promised patch. It turns out protocol validation code was
> a bit (or rather a byte ;) ) off.
> 
> Please let me know if it fixes your touchpad and I believe it would be
> nice to have it in 2.6.11.

Yes, I can't reproduce sync losses that were possible to create with
simultaneous use of the pad anf the touchpoint. Patch applied.

> 
> ===================================================================
> 
> 
> ChangeSet@1.2147, 2005-02-08 18:12:06-05:00, dtor_core@ameritech.net
>   Input: alps - fix protocol validation rules causing touchpad
>          to lose sync if an absolute packet is received after
>          a relative packet with negative Y displacement.
>   
>   Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
>   
> 
> 
>  alps.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> 
> ===================================================================
> 
> 
> 
> diff -Nru a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c
> --- a/drivers/input/mouse/alps.c	2005-02-08 18:16:27 -05:00
> +++ b/drivers/input/mouse/alps.c	2005-02-08 18:16:27 -05:00
> @@ -198,8 +198,8 @@
>  		return PSMOUSE_BAD_DATA;
>  
>  	/* Bytes 2 - 6 should have 0 in the highest bit */
> -	if (psmouse->pktcnt > 1 && psmouse->pktcnt <= 6 &&
> -	    (psmouse->packet[psmouse->pktcnt] & 0x80))
> +	if (psmouse->pktcnt >= 2 && psmouse->pktcnt <= 6 &&
> +	    (psmouse->packet[psmouse->pktcnt - 1] & 0x80))
>  		return PSMOUSE_BAD_DATA;
>  
>  	if (psmouse->pktcnt == 6) {
> 

-- 
Vojtech Pavlik
SuSE Labs, SuSE CR

Re: [PATCH] Fix ALPS sync loss

[Joseph Pingenot]

>From Dmitry Torokhov on Tuesday, 08 February, 2005:
>Hi,
>Here is the promised patch. It turns out protocol validation code was
>a bit (or rather a byte ;) ) off.
>Please let me know if it fixes your touchpad and I believe it would be
>nice to have it in 2.6.11.

This patch seems to be working for me too.  Thanks a million, Dmitry!
  I owe you a beer some time.  :)

-Joseph

>===================================================================
>ChangeSet@1.2147, 2005-02-08 18:12:06-05:00, dtor_core@ameritech.net
>  Input: alps - fix protocol validation rules causing touchpad
>         to lose sync if an absolute packet is received after
>         a relative packet with negative Y displacement.
>  
>  Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
> alps.c |    4 ++--
> 1 files changed, 2 insertions(+), 2 deletions(-)
>===================================================================
>diff -Nru a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c
>--- a/drivers/input/mouse/alps.c	2005-02-08 18:16:27 -05:00
>+++ b/drivers/input/mouse/alps.c	2005-02-08 18:16:27 -05:00
>@@ -198,8 +198,8 @@
> 		return PSMOUSE_BAD_DATA;
> 
> 	/* Bytes 2 - 6 should have 0 in the highest bit */
>-	if (psmouse->pktcnt > 1 && psmouse->pktcnt <= 6 &&
>-	    (psmouse->packet[psmouse->pktcnt] & 0x80))
>+	if (psmouse->pktcnt >= 2 && psmouse->pktcnt <= 6 &&
>+	    (psmouse->packet[psmouse->pktcnt - 1] & 0x80))
> 		return PSMOUSE_BAD_DATA;
> 
> 	if (psmouse->pktcnt == 6) {

-- 
Joseph===============================================trelane@digitasaru.net
      Graduate Student in Physics, Freelance Free Software Developer

Re: [PATCH] Fix ALPS sync loss

[Dmitry Torokhov]

On Wed, 9 Feb 2005 11:35:34 -0600, Joseph Pingenot
<trelane@digitasaru.net> wrote:
> From Dmitry Torokhov on Tuesday, 08 February, 2005:
> >Hi,
> >Here is the promised patch. It turns out protocol validation code was
> >a bit (or rather a byte ;) ) off.
> >Please let me know if it fixes your touchpad and I believe it would be
> >nice to have it in 2.6.11.
> 
> This patch seems to be working for me too.  Thanks a million, Dmitry!
>  I owe you a beer some time.  :)
> 

You are welcome. I am glad we got your touchpad going.

-- 
Dmitry

Re: [PATCH] Fix ALPS sync loss

[Pete Zaitcev]

On Tue, 8 Feb 2005 18:40:12 -0500, Dmitry Torokhov <dtor_core@ameritech.net> wrote:

> Here is the promised patch. It turns out protocol validation code was
> a bit (or rather a byte ;) ) off.

> +++ b/drivers/input/mouse/alps.c	2005-02-08 18:16:27 -05:00
> @@ -198,8 +198,8 @@
>  		return PSMOUSE_BAD_DATA;
>  
>  	/* Bytes 2 - 6 should have 0 in the highest bit */
> -	if (psmouse->pktcnt > 1 && psmouse->pktcnt <= 6 &&
> -	    (psmouse->packet[psmouse->pktcnt] & 0x80))
> +	if (psmouse->pktcnt >= 2 && psmouse->pktcnt <= 6 &&
> +	    (psmouse->packet[psmouse->pktcnt - 1] & 0x80))
>  		return PSMOUSE_BAD_DATA;

This seems to work here, no more dead pad.

-- Pete