Re: [PATCH v8 v8 10/11] iio: adc: hx711: pass iio_chan_spec to hx711_reset_read

[Jonathan Cameron <jic23@kernel.org>]

On Mon, 11 May 2026 23:13:35 +0530
Piyush Patle <piyushpatle228@gmail.com> wrote:

> Change hx711_reset_read() to accept the channel descriptor directly and
> update its callers accordingly.
> 
> Split the existing HX711 channel-selection work into a small helper so a
> later variant-specific change can add a matching helper without growing
> hx711_reset_read() further.
> 
> No functional change.
> 
> Signed-off-by: Piyush Patle <piyushpatle228@gmail.com>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>

Again mostly for my reference (maybe put these under the --- in a patch if we've
discussed it before) the sashiko warning on v7 is a false positive because
we never set the active_scan_mask bit for the timestamp channel.

One day I'll tidy up that index so it doesn't mislead analysis tools and to save
a tiny bit off computation checking a bitmap bit that is never set.
Entirely reasonable that sashiko didn't pick up on that oddity!

Jonathan

> ---
>  drivers/iio/adc/hx711.c | 27 +++++++++++++++++++++------
>  1 file changed, 21 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/iio/adc/hx711.c b/drivers/iio/adc/hx711.c
> index 0db2d2db9242..183568196d52 100644
> --- a/drivers/iio/adc/hx711.c
> +++ b/drivers/iio/adc/hx711.c
> @@ -269,7 +269,23 @@ static int hx711_set_gain_for_channel(struct hx711_data *hx711_data, int chan)
>  	return 0;
>  }
>  
> -static int hx711_reset_read(struct hx711_data *hx711_data, int chan)
> +static int hx711_set_hx711_channel(struct hx711_data *hx711_data,
> +				   const struct iio_chan_spec *chan,
> +				   int *trailing_pulses)
> +{
> +	int ret;
> +
> +	ret = hx711_set_gain_for_channel(hx711_data, chan->channel);
> +	if (ret < 0)
> +		return ret;
> +
> +	*trailing_pulses = hx711_get_gain_to_pulse(hx711_data->gain_set);
> +
> +	return 0;
> +}
> +
> +static int hx711_reset_read(struct hx711_data *hx711_data,
> +			    const struct iio_chan_spec *chan)
>  {
>  	int trailing_pulses;
>  	int ret;
> @@ -283,11 +299,10 @@ static int hx711_reset_read(struct hx711_data *hx711_data, int chan)
>  		return -EIO;
>  	}
>  
> -	ret = hx711_set_gain_for_channel(hx711_data, chan);
> +	ret = hx711_set_hx711_channel(hx711_data, chan, &trailing_pulses);
>  	if (ret < 0)
>  		return ret;
>  
> -	trailing_pulses = hx711_get_gain_to_pulse(hx711_data->gain_set);
>  	return hx711_read(hx711_data, trailing_pulses);
>  }
>  
> @@ -301,7 +316,7 @@ static int hx711_read_raw(struct iio_dev *indio_dev,
>  	case IIO_CHAN_INFO_RAW:
>  		mutex_lock(&hx711_data->lock);
>  
> -		*val = hx711_reset_read(hx711_data, chan->channel);
> +		*val = hx711_reset_read(hx711_data, chan);
>  
>  		mutex_unlock(&hx711_data->lock);
>  
> @@ -391,8 +406,8 @@ static irqreturn_t hx711_trigger(int irq, void *p)
>  	memset(&hx711_data->buffer, 0, sizeof(hx711_data->buffer));
>  
>  	iio_for_each_active_channel(indio_dev, i) {
> -		hx711_data->buffer.channel[j] = hx711_reset_read(hx711_data,
> -					indio_dev->channels[i].channel);
> +		hx711_data->buffer.channel[j] =
> +			hx711_reset_read(hx711_data, &indio_dev->channels[i]);
>  		j++;
>  	}
>