On Thu, Jul 23, 2015 at 05:01:31PM +0200, Bernhard Bender wrote:
> From: Bernhard Bender <[email protected]>
> 
> This patch fixes a problem in the usbtouchscreen driver for DMC TSC-30 touch 
> screen.
> Due to a missing delay between the RESET and SET_RATE commands, the touch 
> screen may
> become unresponsive during system startup or driver loading.
> 
> According to the DMC documentation, a delay is needed after the RESET command 
> to allow
> the chip to complete its internal initialization. As this delay is not 
> guaranteed, we
> had a system where the touch screen occasionally did not send any touch data. 
> There was
> no other indication of the problem.
> 
> The patch fixes the problem by adding a 150ms delay between the RESET and 
> SET_RATE commands.
> 
>         Signed-off-by: Bernhard Bender <[email protected]>
>         Suggested-by: Jakob Mustafa <[email protected]>

Applied, thank you.

> 
> ---
> Bernhard Bender
> Entwicklung
> 
> Bytec Medizintechnik GmbH
> Hermann-Hollerith-Str. 11
> 52249 Eschweiler, Germany
> Tel. +49 (2403) 7829-943
> www.bytecmed.com
> 
> Handelsregister Aachen: HRB 11222
> Ust-ID: DE 121732719
> Geschäftsführer: Dipl.-Ing. Paul Willi Coenen
> 
> 
> diff --git a/drivers/input/touchscreen/usbtouchscreen.c 
> b/drivers/input/touchscreen/usbtouchscreen.c
> old mode 100644
> new mode 100755
> index a096633..4ebff01
> --- a/drivers/input/touchscreen/usbtouchscreen.c
> +++ b/drivers/input/touchscreen/usbtouchscreen.c
> @@ -625,6 +625,9 @@ static int dmc_tsc10_init(struct usbtouch_usb *usbtouch)
>                 goto err_out;
>         }
> 
> +    /* TSC-25 data sheet specifies a delay after the RESET command */
> +    msleep(150);
> +
>         /* set coordinate output rate */
>         buf[0] = buf[1] = 0xFF;
>         ret = usb_control_msg(dev, usb_rcvctrlpipe (dev, 0),
> 
> 
> 
> Diese E-Mail enthält vertrauliche und/oder rechtlich geschützte 
> Informationen. Wenn Sie nicht der richtige Adressat sind oder diese E-Mail 
> irrtümlich erhalten haben, informieren Sie bitte sofort den Absender unter 
> [email protected] und löschen Sie diese Mail. Das unerlaubte Kopieren sowie 
> die unbefugte Weitergabe dieser Mail ist nicht gestattet.
> 
> This message may contain privileged and confidential information intended 
> only for the use of the addressee named above. If you are not the intended 
> recipient of this message you are hereby notified that any use, 
> dissemination, distribution of reproduction of this message is prohibited. If 
> you have received this message in error please notify [email protected]  
> immediately.

-- 
Dmitry
--
To unsubscribe from this list: send the line "unsubscribe linux-input" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to