Re: [PATCH] iio: adc: ad7791: fix IRQ flags

[Jonathan Cameron <jic23@kernel.org>]

On Fri, 20 Jan 2023 13:46:45 +0100
Nuno Sá <nuno.sa@analog.com> wrote:

> The interrupt is triggered on the falling edge rather than being a level
> low interrupt.
> 
> Fixes: da4d3d6bb9f6 ("iio: adc: ad-sigma-delta: Allow custom IRQ flags")
> Signed-off-by: Nuno Sá <nuno.sa@analog.com>

What are the symptoms of this?  Given the ad_sigma_delta.c irq handler
disables the interrupt until after the data read is done (at which point the
level is presumably high again), I don't immediately see why the change
here has any impact - either we trigger on the fall, or on the fact it
has become low..

Or is there a board other there that only does end interrupts that is causing
problems?

Jonathan

> ---
>  drivers/iio/adc/ad7791.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/adc/ad7791.c b/drivers/iio/adc/ad7791.c
> index fee8d129a5f0..86effe8501b4 100644
> --- a/drivers/iio/adc/ad7791.c
> +++ b/drivers/iio/adc/ad7791.c
> @@ -253,7 +253,7 @@ static const struct ad_sigma_delta_info ad7791_sigma_delta_info = {
>  	.has_registers = true,
>  	.addr_shift = 4,
>  	.read_mask = BIT(3),
> -	.irq_flags = IRQF_TRIGGER_LOW,
> +	.irq_flags = IRQF_TRIGGER_FALLING,
>  };
>  
>  static int ad7791_read_raw(struct iio_dev *indio_dev,