4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Anders Darander <anders@xxxxxxxxxxxxxx> 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@xxxxxxxxxxxxxx> Acked-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx> Signed-off-by: Jonathan Cameron <jic23@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html