Re: [PATCH] ASoC: SDCA: support Q7.8 volume format

[Charles Keepax <ckeepax@opensource.cirrus.com>]

On Wed, Nov 05, 2025 at 05:11:22PM +0800, shumingf@realtek.com wrote:
> From: Shuming Fan <shumingf@realtek.com>
> 
> The SDCA specification uses Q7.8 volume format.
> This patch adds a field to indicate whether it is SDCA volume control
> and supports the volume settings.
> 
> Signed-off-by: Shuming Fan <shumingf@realtek.com>
> ---
>  include/sound/soc.h        |  1 +
>  sound/soc/sdca/sdca_asoc.c | 34 ++++++---------------
>  sound/soc/soc-ops.c        | 62 +++++++++++++++++++++++++++++++-------

Mark, how do you feel about putting this in soc-ops? I think I
am good with putting it here, the code is definitely a little
smaller than open coding helpers in the SDCA code. However, I
do have a slight doubt that this doesn't have great reusability
outside of SDCA.

> +static int sdca_soc_q78_reg_to_ctl(struct soc_mixer_control *mc, unsigned int reg_val,
> +				unsigned int mask, unsigned int shift, int max)
> +{
> +	int val = reg_val;
> +
> +	if (WARN_ON(!mc->shift))

We should use the function argument for shift in these functions.

>  static int soc_mixer_reg_to_ctl(struct soc_mixer_control *mc, unsigned int reg_val,
>  				unsigned int mask, unsigned int shift, int max)
>  {
> @@ -202,14 +232,22 @@ static int soc_put_volsw(struct snd_kcontrol *kcontrol,
>  	unsigned int val2 = 0;
>  	bool double_r = false;
>  	int ret;
> +	unsigned int (*ctl_to_reg)(struct soc_mixer_control *, int, unsigned int, unsigned int, int);

Would be nice to put this at the top of the variable list, given
the length.

Thanks,
Charles