Commit 2adb9833 authored by Mark Brown's avatar Mark Brown
Browse files

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: default avatarMark Brown <broonie@opensource.wolfsonmicro.com>
parent be1b87c7

sound/soc/codecs/wm8990.c

+11 −0
Original line number Diff line number Diff line
@@ -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:

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