Re: [PATCH v6 6/6] iio: filter: admv8818: Support frequencies >= 2^32

[Jonathan Cameron <jic23@kernel.org>]

On Fri,  7 Mar 2025 10:02:16 -0500
Sam Winchenbach <sam.winchenbach@framepointer.org> wrote:

> From: Brian Pellegrino <bpellegrino@arka.org>
> 
> This patch allows writing u64 values to the ADMV8818's high and low-pass
> filter frequencies. It includes the following changes:
> 
> - Rejects negative frequencies in admv8818_write_raw.
> - Adds a write_raw_get_fmt function to admv8818's iio_info, returning
>   IIO_VAL_INT_64 for the high and low-pass filter 3dB frequency channels.
> 
> Fixes: f34fe888ad05 ("iio:filter:admv8818: add support for ADMV8818")
> Signed-off-by: Brian Pellegrino <bpellegrino@arka.org>
> Signed-off-by: Sam Winchenbach <sam.winchenbach@framepointer.org>
I only have that minor comment on patch 5.  If nothing else comes up
and the dt binding ack comes in I may just tidy that up whilst applying.

> ---
>  drivers/iio/filter/admv8818.c | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
> 
> diff --git a/drivers/iio/filter/admv8818.c b/drivers/iio/filter/admv8818.c
> index e9602bfd4af7..9785533d0cdd 100644
> --- a/drivers/iio/filter/admv8818.c
> +++ b/drivers/iio/filter/admv8818.c
> @@ -402,6 +402,19 @@ static int admv8818_read_lpf_freq(struct admv8818_state *st, u64 *lpf_freq)
>  	return ret;
>  }
>  
> +static int admv8818_write_raw_get_fmt(struct iio_dev *indio_dev,
> +								struct iio_chan_spec const *chan,
> +								long mask)
> +{
> +	switch (mask) {
> +	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
> +	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
> +		return IIO_VAL_INT_64;
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
>  static int admv8818_write_raw(struct iio_dev *indio_dev,
>  			      struct iio_chan_spec const *chan,
>  			      int val, int val2, long info)
> @@ -410,6 +423,9 @@ static int admv8818_write_raw(struct iio_dev *indio_dev,
>  
>  	u64 freq = ((u64)val2 << 32 | (u32)val);
>  
> +	if ((s64)freq < 0)
> +		return -EINVAL;
> +
>  	switch (info) {
>  	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
>  		return admv8818_lpf_select(st, freq);
> @@ -571,6 +587,7 @@ static int admv8818_set_mode(struct iio_dev *indio_dev,
>  
>  static const struct iio_info admv8818_info = {
>  	.write_raw = admv8818_write_raw,
> +	.write_raw_get_fmt = admv8818_write_raw_get_fmt,
>  	.read_raw = admv8818_read_raw,
>  	.debugfs_reg_access = &admv8818_reg_access,
>  };