Re: [PATCH 1/2] iio: adc: ad7124: Don't create more channels than the hardware is capable of

From: Nuno Sá
Date: Mon Nov 11 2024 - 05:33:36 EST


On Fri, 2024-11-08 at 19:18 +0100, Uwe Kleine-König wrote:
> The ad7124-4 and ad7124-8 both support 16 channel registers. Don't
> accept more (logical) channels from dt than that.
>
> Fixes: b3af341bbd96 ("iio: adc: Add ad7124 support")
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxx>
> ---
>  drivers/iio/adc/ad7124.c | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/drivers/iio/adc/ad7124.c b/drivers/iio/adc/ad7124.c
> index a5d91933f505..7473bcef7bc6 100644
> --- a/drivers/iio/adc/ad7124.c
> +++ b/drivers/iio/adc/ad7124.c
> @@ -18,6 +18,7 @@
>  #include <linux/property.h>
>  #include <linux/regulator/consumer.h>
>  #include <linux/spi/spi.h>
> +#include <linux/stringify.h>
>  
>  #include <linux/iio/iio.h>
>  #include <linux/iio/adc/ad_sigma_delta.h>
> @@ -821,6 +822,11 @@ static int ad7124_parse_channel_config(struct iio_dev
> *indio_dev,
>   if (!st->num_channels)
>   return dev_err_probe(dev, -ENODEV, "no channel children\n");
>  
> + if (st->num_channels > AD7124_MAX_CHANNELS) {
> + dev_warn(dev, "Limit number of channels to "
> __stringify(AD7124_MAX_CHANNELS) "\n");
> + st->num_channels = AD7124_MAX_CHANNELS;
> + }

Hmmm, I would treat it as an error...

- Nuno Sá