Patch "iio: adc: at91: unbreak channel adc channel 3" has been added to the 4.4-stable tree

Patch "iio: adc: at91: unbreak channel adc channel 3" has been added to the 4.4-stable tree

[gregkh]

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

    iio: adc: at91: unbreak channel adc channel 3

to the 4.4-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:
     iio-adc-at91-unbreak-channel-adc-channel-3.patch
and it can be found in the queue-4.4 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 c2ab447454d498e709d9011c0f2d2945ee321f9b Mon Sep 17 00:00:00 2001
From: Anders Darander <anders@chargestorm.se>
Date: Mon, 8 Aug 2016 14:42:16 +0200
Subject: iio: adc: at91: unbreak channel adc channel 3

From: Anders Darander <anders@chargestorm.se>

commit c2ab447454d498e709d9011c0f2d2945ee321f9b upstream.

The driver always assumes that an input device has been created when
reading channel 3. This causes a kernel panic when dereferencing
st->ts_input.

The change was introduced in
commit 84882b060301 ("iio: adc: at91_adc: Add support for touchscreens
without TSMR"). Earlier versions only entered that part of the if-else
statement if only the following flags are set:

AT91_ADC_IER_XRDY | AT91_ADC_IER_YRDY | AT91_ADC_IER_PRDY

Signed-off-by: Anders Darander <anders@chargestorm.se>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/iio/adc/at91_adc.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -381,8 +381,8 @@ static irqreturn_t at91_adc_rl_interrupt
 		st->ts_bufferedmeasure = false;
 		input_report_key(st->ts_input, BTN_TOUCH, 0);
 		input_sync(st->ts_input);
-	} else if (status & AT91_ADC_EOC(3)) {
-		/* Conversion finished */
+	} else if (status & AT91_ADC_EOC(3) && st->ts_input) {
+		/* Conversion finished and we've a touchscreen */
 		if (st->ts_bufferedmeasure) {
 			/*
 			 * Last measurement is always discarded, since it can


Patches currently in stable-queue which might be from anders@chargestorm.se are

queue-4.4/iio-adc-at91-unbreak-channel-adc-channel-3.patch