[alsa-devel] [PATCH] ASoC: Add info callback for SX_TLV controls

[Brian Austin]

> SX_TLV controls are intended for situations where the register behind
> the control has some non-zero value indicating the minimum gain
> and then gains increasing from there and eventually overflowing through
> zero.
> 
> Currently every CODEC implementing these controls specifies the minimum
> as the non-zero value for the minimum and the maximum as the number of
> gain settings available.
> 
> This means when the info callback subtracts the minimum value from the
> maximum value to calculate the number of gain levels available it is
> actually under reporting the available levels. This patch fixes this
> issue by adding a new snd_soc_info_volsw_sx callback that does not
> subtract the minimum value.
> 
> Fixes: 1d99f2436d0d ("ASoC: core: Rework SOC_DOUBLE_R_SX_TLV add SOC_SINGLE_SX_TLV")
> Signed-off-by: Charles Keepax <ckeepax at opensource.wolfsonmicro.com>
> ---
Scales correctly on CS42L73 'Headphone Analog Playback Volume'
Tested-by: Brian Austin <brian.austin at cirrus.com>