On 08/08/2016 at 14:42:16 +0200, Anders Darander wrote :
> 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 <and...@chargestorm.se>
Acked-by: Alexandre Belloni <alexandre.bell...@free-electrons.com>
> ---
> drivers/iio/adc/at91_adc.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
> index 52430ba..0438c68 100644
> --- 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(int irq, void
> *private)
> 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
> --
> 2.8.1
>
--
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
