ASoC: wm8994: Only enable extra BCLK cycles when required

Rather than always assuming the maximum possible BCLK rate will be
required generate BCLKs for stereo if either one or two channels is
enabled. In order to support this we also need to ensure that only
the relevant channels are enabled.

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

diff --git a/sound/soc/codecs/wm8994.c b/sound/soc/codecs/wm8994.c
index 2b2dadc54dac5cfe729ddc2fd402e748195a6882..3fddc7ad1127eb9408bc6d2cddd7499e7b03ec39 100644 (file)
--- a/sound/soc/codecs/wm8994.c
+++ b/sound/soc/codecs/wm8994.c
@@ -1045,6 +1045,7 @@ static int aif1clk_ev(struct snd_soc_dapm_widget *w,
                      struct snd_kcontrol *kcontrol, int event)
 {
        struct snd_soc_codec *codec = w->codec;
+       struct wm8994_priv *wm8994 = snd_soc_codec_get_drvdata(codec);
        struct wm8994 *control = codec->control_data;
        int mask = WM8994_AIF1DAC1L_ENA | WM8994_AIF1DAC1R_ENA;
        int i;
@@ -1063,6 +1064,10 @@ static int aif1clk_ev(struct snd_soc_dapm_widget *w,
 
        switch (event) {
        case SND_SOC_DAPM_PRE_PMU:
+               /* Don't enable timeslot 2 if not in use */
+               if (wm8994->channels[0] <= 2)
+                       mask &= ~(WM8994_AIF1DAC2L_ENA | WM8994_AIF1DAC2R_ENA);
+
                val = snd_soc_read(codec, WM8994_AIF1_CONTROL_1);
                if ((val & WM8994_AIF1ADCL_SRC) &&
                    (val & WM8994_AIF1ADCR_SRC))
@@ -2687,7 +2692,7 @@ static int wm8994_hw_params(struct snd_pcm_substream *substream,
                return -EINVAL;
        }
 
-       bclk_rate = params_rate(params) * 4;
+       bclk_rate = params_rate(params);
        switch (params_format(params)) {
        case SNDRV_PCM_FORMAT_S16_LE:
                bclk_rate *= 16;
@@ -2708,6 +2713,17 @@ static int wm8994_hw_params(struct snd_pcm_substream *substream,
                return -EINVAL;
        }
 
+       wm8994->channels[id] = params_channels(params);
+       switch (params_channels(params)) {
+       case 1:
+       case 2:
+               bclk_rate *= 2;
+               break;
+       default:
+               bclk_rate *= 4;
+               break;
+       }
+
        /* Try to find an appropriate sample rate; look for an exact match. */
        for (i = 0; i < ARRAY_SIZE(srs); i++)
                if (srs[i].rate == params_rate(params))

diff --git a/sound/soc/codecs/wm8994.h b/sound/soc/codecs/wm8994.h
index f142ec198db3dabfcfc5d1e20a51cdfd5e42874b..ccbce5791e95829b5d98ce472ac50d922e6e4703 100644 (file)
--- a/sound/soc/codecs/wm8994.h
+++ b/sound/soc/codecs/wm8994.h
@@ -77,6 +77,7 @@ struct wm8994_priv {
        int sysclk_rate[2];
        int mclk[2];
        int aifclk[2];
+       int channels[2];
        struct wm8994_fll_config fll[2], fll_suspend[2];
        struct completion fll_locked[2];
        bool fll_locked_irq;