On Wed, Feb 19, 2020 at 05:16:25PM +0100, Jerome Brunet wrote:

> +	SOC_SINGLE("Playback Mute Switch", VOL_CTRL1, DAC_SOFT_MUTE, 1, 0),
> +	SOC_DOUBLE_TLV("Playback Volume", VOL_CTRL1, DACL_VC, DACR_VC,
> +		       0xff, 0, dac_vol_tlv),

Sorry, that should just be plain "Playback Switch" - this can be used by
applications to present a combined mute/volume control together with the
Volume control (though as in this case there's no per-channel control it
is possible some applications will struggle with that).