ASoC: Clean up WM8731 bias level configuration

The WM8731 bias level configuration function was written slightly
obscurely - streamline the code a little and refresh the comments.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

diff --git a/sound/soc/codecs/wm8731.c b/sound/soc/codecs/wm8731.c
index 816e5bf..c6db677 100644 (file)
--- a/sound/soc/codecs/wm8731.c
+++ b/sound/soc/codecs/wm8731.c
@@ -396,21 +396,19 @@ static int wm8731_set_dai_fmt(struct snd_soc_dai *codec_dai,
 static int wm8731_set_bias_level(struct snd_soc_codec *codec,
                                 enum snd_soc_bias_level level)
 {
-       u16 reg = wm8731_read_reg_cache(codec, WM8731_PWR) & 0xff7f;
+       u16 reg;
 
        switch (level) {
        case SND_SOC_BIAS_ON:
-               /* vref/mid, osc on, dac unmute */
-               wm8731_write(codec, WM8731_PWR, reg);
                break;
        case SND_SOC_BIAS_PREPARE:
                break;
        case SND_SOC_BIAS_STANDBY:
-               /* everything off except vref/vmid, */
+               /* Clear PWROFF, gate CLKOUT, everything else as-is */
+               reg = wm8731_read_reg_cache(codec, WM8731_PWR) & 0xff7f;
                wm8731_write(codec, WM8731_PWR, reg | 0x0040);
                break;
        case SND_SOC_BIAS_OFF:
-               /* everything off, dac mute, inactive */
                wm8731_write(codec, WM8731_ACTIVE, 0x0);
                wm8731_write(codec, WM8731_PWR, 0xffff);
                break;