On Fri, Aug 08, 2025 at 11:52:13AM +0300, Matti Vaittinen wrote:
> The ad7476 driver supports ADCs which require a GPIO pin to be used to
> start conversion. The GPIO line status seems to be always toggled from
> a process context, either from the user-initiated "raw-read conversion",
> or from a threaded IRQ handler. Furthermore, these ICs are connected via
> SPI bus, which is usually implemented in a way that the access to the
> device can sleep. The GPIO here is toggled from the same context which
> is reading the results over SPI.
>
> Thus it seems very likely these GPIOs are toggled from a context which
> can sleep.
>
> Swap the gpiod_set_value() to gpiod_set_value_cansleep() accordinlgy.
>
> Suggested-by: Nuno Sá <noname.nuno@gmail.com>
> Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
>
> ---
> Revision history:
> v2 => v3:
> - New patch
> ---
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
> drivers/iio/adc/ad7476.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/adc/ad7476.c b/drivers/iio/adc/ad7476.c
> index fc701267358e..1445f0f599d9 100644
> --- a/drivers/iio/adc/ad7476.c
> +++ b/drivers/iio/adc/ad7476.c
> @@ -57,9 +57,9 @@ static void ad7091_convst(struct ad7476_state *st)
> if (!st->convst_gpio)
> return;
>
> - gpiod_set_value(st->convst_gpio, 0);
> + gpiod_set_value_cansleep(st->convst_gpio, 0);
> udelay(1); /* CONVST pulse width: 10 ns min */
> - gpiod_set_value(st->convst_gpio, 1);
> + gpiod_set_value_cansleep(st->convst_gpio, 1);
> udelay(1); /* Conversion time: 650 ns max */
> }
>
> --
> 2.50.1
>