WM8990_DAC_MUTE
val = snd_soc_component_read(component, WM8990_DAC_CTRL) & ~WM8990_DAC_MUTE;
snd_soc_component_write(component, WM8990_DAC_CTRL, val | WM8990_DAC_MUTE);
WM8990_DAC_MUTE, WM8990_DAC_MUTE);