> Currently MCLK remains enabled during bias STANDBY state, and this
> is not necessary. This patch updates the code to handle enabling
> and disabling of MCLK, if provided, when moving between STANDBY
> and PREPARE states, therefore saving power when no active streams
> present.
>
> Signed-off-by: Adam Thomson <adam.thomson.opensou...@diasemi.com>
Tested-by: Peter Meerwald-Stadler <pme...@pmeerw.net>
> ---
> sound/soc/codecs/da7213.c | 20 +++++++++++---------
> 1 file changed, 11 insertions(+), 9 deletions(-)
>
> diff --git a/sound/soc/codecs/da7213.c b/sound/soc/codecs/da7213.c
> index bcf1834..7701f4e 100644
> --- a/sound/soc/codecs/da7213.c
> +++ b/sound/soc/codecs/da7213.c
> @@ -1454,11 +1454,10 @@ static int da7213_set_bias_level(struct snd_soc_codec
> *codec,
>
> switch (level) {
> case SND_SOC_BIAS_ON:
> - case SND_SOC_BIAS_PREPARE:
> break;
> - case SND_SOC_BIAS_STANDBY:
> - if (snd_soc_codec_get_bias_level(codec) == SND_SOC_BIAS_OFF) {
> - /* MCLK */
> + case SND_SOC_BIAS_PREPARE:
> + /* Enable MCLK for transition to ON state */
> + if (snd_soc_codec_get_bias_level(codec) ==
> SND_SOC_BIAS_STANDBY) {
> if (da7213->mclk) {
> ret = clk_prepare_enable(da7213->mclk);
> if (ret) {
> @@ -1467,21 +1466,24 @@ static int da7213_set_bias_level(struct snd_soc_codec
> *codec,
> return ret;
> }
> }
> -
> + }
> + break;
> + case SND_SOC_BIAS_STANDBY:
> + if (snd_soc_codec_get_bias_level(codec) == SND_SOC_BIAS_OFF) {
> /* Enable VMID reference & master bias */
> snd_soc_update_bits(codec, DA7213_REFERENCES,
> DA7213_VMID_EN | DA7213_BIAS_EN,
> DA7213_VMID_EN | DA7213_BIAS_EN);
> + } else {
> + /* Remove MCLK */
> + if (da7213->mclk)
> + clk_disable_unprepare(da7213->mclk);
> }
> break;
> case SND_SOC_BIAS_OFF:
> /* Disable VMID reference & master bias */
> snd_soc_update_bits(codec, DA7213_REFERENCES,
> DA7213_VMID_EN | DA7213_BIAS_EN, 0);
> -
> - /* MCLK */
> - if (da7213->mclk)
> - clk_disable_unprepare(da7213->mclk);
> break;
> }
> return 0;
>
--
Peter Meerwald-Stadler
+43-664-2444418 (mobile)
