From be1898c25d776060d74483696feb8b4638e2655a Mon Sep 17 00:00:00 2001 From: Eugen Hristev Date: Mon, 24 Sep 2018 10:51:43 +0300 Subject: iio: adc: at91: fix acking DRDY irq on simple conversions commit bc1b45326223e7e890053cf6266357adfa61942d upstream. When doing simple conversions, the driver did not acknowledge the DRDY irq. If this irq status is not acked, it will be left pending, and as soon as a trigger is enabled, the irq handler will be called, it doesn't know why this status has occurred because no channel is pending, and then it will go int a irq loop and board will hang. To avoid this situation, read the LCDR after a raw conversion is done. Fixes: 0e589d5fb ("ARM: AT91: IIO: Add AT91 ADC driver.") Cc: Maxime Ripard Signed-off-by: Eugen Hristev Acked-by: Ludovic Desroches Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- drivers/iio/adc/at91_adc.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/iio') diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c index bbdac07f4aaa..5b8d6b60d45a 100644 --- a/drivers/iio/adc/at91_adc.c +++ b/drivers/iio/adc/at91_adc.c @@ -278,6 +278,8 @@ static void handle_adc_eoc_trigger(int irq, struct iio_dev *idev) iio_trigger_poll(idev->trig); } else { st->last_value = at91_adc_readl(st, AT91_ADC_CHAN(st, st->chnb)); + /* Needed to ACK the DRDY interruption */ + at91_adc_readl(st, AT91_ADC_LCDR); st->done = true; wake_up_interruptible(&st->wq_data_avail); } -- cgit v1.2.3