From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934559AbcKNDQs (ORCPT ); Sun, 13 Nov 2016 22:16:48 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:45294 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754025AbcKNCFm (ORCPT ); Sun, 13 Nov 2016 21:05:42 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Anders Darander" , "Alexandre Belloni" , "Jonathan Cameron" Date: Mon, 14 Nov 2016 00:14:20 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 186/346] iio: adc: at91: unbreak channel adc channel 3 In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.39-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Anders Darander 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 Acked-by: Alexandre Belloni Signed-off-by: Jonathan Cameron Signed-off-by: Ben Hutchings --- 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