The threshold event handler is being called before the FIFO has actually reached the threshold. The current code receives a FIFO threshold event, masks the interrupt, clears the event, and schedules a workqueue. The workqueue is run, it empties the FIFO, and unmasks the interrupt. In the above sequence, after the event is cleared, it immediately retriggers since the FIFO remains beyond the threshold. When the IRQ is unmasked, this triggered event generates another IRQ. However, as the FIFO has just been emptied, it is likely to not contain enough samples. The waits to clear the event until the FIFO has actually been emptied, in the workqueue. The unmasking and masking of the interrupt remains unchanged. Signed-off-by: Russ Dill <Russ.Dill@xxxxxx> Signed-off-by: Zubair Lutfullah <zubair.lutfullah@xxxxxxxxx> --- drivers/iio/adc/ti_am335x_adc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c index e510da7..fcd414d 100644 --- a/drivers/iio/adc/ti_am335x_adc.c +++ b/drivers/iio/adc/ti_am335x_adc.c @@ -193,8 +193,7 @@ static irqreturn_t tiadc_irq(int irq, void *private) } else { wake_up_interruptible(&adc_dev->wq_data_avail); } - tiadc_writel(adc_dev, REG_IRQSTATUS, - IRQENB_FIFO1THRES); + return IRQ_HANDLED; } else { return IRQ_NONE; @@ -230,6 +229,8 @@ static void tiadc_poll_handler(struct work_struct *work_s) } buffer->access->store_to(buffer, (u8 *) iBuf); + tiadc_writel(adc_dev, REG_IRQSTATUS, + IRQENB_FIFO1THRES); tiadc_writel(adc_dev, REG_IRQENABLE, IRQENB_FIFO1THRES); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html