ASoC: Manage VMID mode for WM8990

A small additional power saving can be achieved for the WM8990 by
maintaining VMID using a 2*250k divider when in standby mode.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Mark Brown 2008-11-17 17:11:14 +00:00
parent be1b87c70a
commit 2adb9833d1

View File

@ -1222,8 +1222,14 @@ static int wm8990_set_bias_level(struct snd_soc_codec *codec,
switch (level) {
case SND_SOC_BIAS_ON:
break;
case SND_SOC_BIAS_PREPARE:
/* VMID=2*50k */
val = wm8990_read_reg_cache(codec, WM8990_POWER_MANAGEMENT_1) &
~WM8990_VMID_MODE_MASK;
wm8990_write(codec, WM8990_POWER_MANAGEMENT_1, val | 0x2);
break;
case SND_SOC_BIAS_STANDBY:
if (codec->bias_level == SND_SOC_BIAS_OFF) {
/* Enable all output discharge bits */
@ -1278,6 +1284,11 @@ static int wm8990_set_bias_level(struct snd_soc_codec *codec,
wm8990_write(codec, WM8990_EXT_CTL1, 0xa003);
wm8990_write(codec, WM8990_EXT_ACCESS_ENA, 0);
}
/* VMID=2*250k */
val = wm8990_read_reg_cache(codec, WM8990_POWER_MANAGEMENT_1) &
~WM8990_VMID_MODE_MASK;
wm8990_write(codec, WM8990_POWER_MANAGEMENT_1, val | 0x4);
break;
case SND_SOC_BIAS_OFF: