Patch "Input: usbtouchscreen - avoid unresponsive TSC-30 touch screen" has been added to the 4.1-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    Input: usbtouchscreen - avoid unresponsive TSC-30 touch screen

to the 4.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     input-usbtouchscreen-avoid-unresponsive-tsc-30-touch-screen.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 968491709e5b1aaf429428814fff3d932fa90b60 Mon Sep 17 00:00:00 2001
From: Bernhard Bender <bernhard.bender@bytecmed.com>
Date: Thu, 23 Jul 2015 13:58:08 -0700
Subject: Input: usbtouchscreen - avoid unresponsive TSC-30 touch screen

From: Bernhard Bender <bernhard.bender@bytecmed.com>

commit 968491709e5b1aaf429428814fff3d932fa90b60 upstream.

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.

Suggested-by: Jakob Mustafa <jakob.mustafa@bytecmed.com>
Signed-off-by: Bernhard Bender <bernhard.bender@bytecmed.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/input/touchscreen/usbtouchscreen.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/input/touchscreen/usbtouchscreen.c
+++ b/drivers/input/touchscreen/usbtouchscreen.c
@@ -627,6 +627,9 @@ static int dmc_tsc10_init(struct usbtouc
 		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),


Patches currently in stable-queue which might be from bernhard.bender@bytecmed.com are

queue-4.1/input-usbtouchscreen-avoid-unresponsive-tsc-30-touch-screen.patch