ASoC: littlemill: Use a widget to keep track of AIF2 clocking

Since we only need to clock AIF2 when it's actively in use start up the
FLL for it using a supply widget which supplies AIF2CLK. This both makes
the sequencing more robust and ensures we minimise power consumption.

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

diff --git a/sound/soc/samsung/littlemill.c b/sound/soc/samsung/littlemill.c
index fd5ac47..c82c646 100644 (file)
--- a/sound/soc/samsung/littlemill.c
+++ b/sound/soc/samsung/littlemill.c
@@ -67,7 +67,6 @@ static int littlemill_set_bias_level_post(struct snd_soc_card *card,
                                               enum snd_soc_bias_level level)
 {
        struct snd_soc_dai *aif1_dai = card->rtd[0].codec_dai;
-       struct snd_soc_dai *aif2_dai = card->rtd[1].cpu_dai;
        int ret;
 
        if (dapm->dev != aif1_dai->dev)
@@ -75,20 +74,6 @@ static int littlemill_set_bias_level_post(struct snd_soc_card *card,
 
        switch (level) {
        case SND_SOC_BIAS_STANDBY:
-               ret = snd_soc_dai_set_sysclk(aif2_dai, WM8994_SYSCLK_MCLK2,
-                                            32768, SND_SOC_CLOCK_IN);
-               if (ret < 0) {
-                       pr_err("Failed to switch away from FLL2: %d\n", ret);
-                       return ret;
-               }
-
-               ret = snd_soc_dai_set_pll(aif2_dai, WM8994_FLL2,
-                                         0, 0, 0);
-               if (ret < 0) {
-                       pr_err("Failed to stop FLL2: %d\n", ret);
-                       return ret;
-               }
-
                ret = snd_soc_dai_set_sysclk(aif1_dai, WM8994_SYSCLK_MCLK2,
                                             32768, SND_SOC_CLOCK_IN);
                if (ret < 0) {
@@ -104,24 +89,6 @@ static int littlemill_set_bias_level_post(struct snd_soc_card *card,
                }
                break;
 
-       case SND_SOC_BIAS_PREPARE:
-               ret = snd_soc_dai_set_pll(aif2_dai, WM8994_FLL2,
-                                         WM8994_FLL_SRC_BCLK, 64 * 8000,
-                                         8000 * 256);
-               if (ret < 0) {
-                       pr_err("Failed to start FLL: %d\n", ret);
-                       return ret;
-               }
-
-               ret = snd_soc_dai_set_sysclk(aif2_dai, WM8994_SYSCLK_FLL2,
-                                            8000 * 256,
-                                            SND_SOC_CLOCK_IN);
-               if (ret < 0) {
-                       pr_err("Failed to set SYSCLK: %d\n", ret);
-                       return ret;
-               }
-               break;
-
        default:
                break;
        }
@@ -197,11 +164,62 @@ static struct snd_soc_dai_link littlemill_dai[] = {
        },
 };
 
+static int bbclk_ev(struct snd_soc_dapm_widget *w,
+                   struct snd_kcontrol *kcontrol, int event)
+{
+       struct snd_soc_card *card = w->dapm->card;
+       struct snd_soc_dai *aif2_dai = card->rtd[1].cpu_dai;
+       int ret;
+
+       switch (event) {
+       case SND_SOC_DAPM_PRE_PMU:
+               ret = snd_soc_dai_set_pll(aif2_dai, WM8994_FLL2,
+                                         WM8994_FLL_SRC_BCLK, 64 * 8000,
+                                         8000 * 256);
+               if (ret < 0) {
+                       pr_err("Failed to start FLL: %d\n", ret);
+                       return ret;
+               }
+
+               ret = snd_soc_dai_set_sysclk(aif2_dai, WM8994_SYSCLK_FLL2,
+                                            8000 * 256,
+                                            SND_SOC_CLOCK_IN);
+               if (ret < 0) {
+                       pr_err("Failed to set SYSCLK: %d\n", ret);
+                       return ret;
+               }
+               break;
+       case SND_SOC_DAPM_POST_PMD:
+               ret = snd_soc_dai_set_sysclk(aif2_dai, WM8994_SYSCLK_MCLK2,
+                                            32768, SND_SOC_CLOCK_IN);
+               if (ret < 0) {
+                       pr_err("Failed to switch away from FLL2: %d\n", ret);
+                       return ret;
+               }
+
+               ret = snd_soc_dai_set_pll(aif2_dai, WM8994_FLL2,
+                                         0, 0, 0);
+               if (ret < 0) {
+                       pr_err("Failed to stop FLL2: %d\n", ret);
+                       return ret;
+               }
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
 static struct snd_soc_dapm_widget widgets[] = {
        SND_SOC_DAPM_HP("Headphone", NULL),
 
        SND_SOC_DAPM_MIC("AMIC", NULL),
        SND_SOC_DAPM_MIC("DMIC", NULL),
+
+       SND_SOC_DAPM_SUPPLY_S("Baseband Clock", -1, SND_SOC_NOPM, 0, 0,
+                             bbclk_ev,
+                             SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMD),
 };
 
 static struct snd_soc_dapm_route audio_paths[] = {
@@ -214,6 +232,8 @@ static struct snd_soc_dapm_route audio_paths[] = {
        { "DMIC", NULL, "MICBIAS2" },   /* Default for DMICBIAS jumper */
        { "DMIC1DAT", NULL, "DMIC" },
        { "DMIC2DAT", NULL, "DMIC" },
+
+       { "AIF2CLK", NULL, "Baseband Clock" },
 };
 
 static struct snd_soc_jack littlemill_headset;