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[PATCH 3.14 15/29] Input: usbtouchscreen - avoid unresponsive TSC-30 touch screen

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3.14-stable review patch.  If anyone has any objections, please let me know.

------------------

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
@@ -625,6 +625,9 @@ 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),


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[PATCH 3.14 00/29] 3.14.50-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 11/29] mmc: sdhci-esdhc: Make 8BIT bus work Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 04/29] ARC: make sure instruction_pointer() returns unsigned value Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 26/29] avr32: handle NULL as a valid clock object Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 07/29] ALSA: usb-audio: add dB range mapping for some devices Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 15/29] Input: usbtouchscreen - avoid unresponsive TSC-30 touch screen Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 16/29] blkcg: fix gendisk reference leak in blkg_conf_prep() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 17/29] ata: pmp: add quirk for Marvell 4140 SATA PMP Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 24/29] rds: rds_ib_device.refcount overflow Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 23/29] x86/efi: Use all 64 bit of efi_memmap in setup_e820() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 20/29] xhci: report U3 when link is in resume state Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 10/29] mac80211: clear subdir_stations when removing debugfs Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 19/29] xhci: Calculate old endpoints correctly on device reset Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 03/29] s390/sclp: clear upper register halves in _sclp_print_early Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 27/29] iscsi-target: Fix use-after-free during TPG session shutdown Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 02/29] freeing unlinked file indefinitely delayed Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  [PATCH 3.14 01/29] mm: avoid setting up anonymous pages into file mapping Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-09 00:50 +0200
  Re: [PATCH 3.14 00/29] 3.14.50-stable review Guenter Roeck <linux@roeck-us.net> - 2015-08-09 05:20 +0200
    Re: [PATCH 3.14 00/29] 3.14.50-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-08-10 21:20 +0200
  Re: [PATCH 3.14 00/29] 3.14.50-stable review Sudip Mukherjee <sudipm.mukherjee@gmail.com> - 2015-08-10 07:10 +0200

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