ASoC: da7213: Add checking of SRM lock status before enabling DAI
authorAdam Thomson <Adam.Thomson.Opensource@diasemi.com>
Tue, 10 May 2016 15:11:05 +0000 (16:11 +0100)
committerMark Brown <broonie@kernel.org>
Tue, 10 May 2016 18:24:19 +0000 (19:24 +0100)
When the codec is DAI clk slave, and the SRM feature of the PLL
is being used, the enabling of the DAI should occur only after
the PLL has locked to the incoming WCLK. This update adds checking
to the the DAI widget event, so it waits for SRM to lock. There is
also a timeout if that lock doesn't occur within a given time.

Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
sound/soc/codecs/da7213.c
sound/soc/codecs/da7213.h

index 701bd620474709dcf500687cef0eb0292862c1a7..680d11116ccfa249d98f1dd9da309b256ecb24c5 100644 (file)
@@ -734,6 +734,9 @@ static int da7213_dai_event(struct snd_soc_dapm_widget *w,
 {
        struct snd_soc_codec *codec = snd_soc_dapm_to_codec(w->dapm);
        struct da7213_priv *da7213 = snd_soc_codec_get_drvdata(codec);
+       u8 pll_ctrl, pll_status;
+       int i = 0;
+       bool srm_lock = false;
 
        switch (event) {
        case SND_SOC_DAPM_PRE_PMU:
@@ -742,6 +745,26 @@ static int da7213_dai_event(struct snd_soc_dapm_widget *w,
                        snd_soc_update_bits(codec, DA7213_DAI_CLK_MODE,
                                            DA7213_DAI_CLK_EN_MASK,
                                            DA7213_DAI_CLK_EN_MASK);
+
+               /* Slave mode, if SRM not enabled no need for status checks */
+               pll_ctrl = snd_soc_read(codec, DA7213_PLL_CTRL);
+               if (!(pll_ctrl & DA7213_PLL_SRM_EN))
+                       return 0;
+
+               /* Check SRM has locked */
+               do {
+                       pll_status = snd_soc_read(codec, DA7213_PLL_STATUS);
+                       if (pll_status & DA7219_PLL_SRM_LOCK) {
+                               srm_lock = true;
+                       } else {
+                               ++i;
+                               msleep(50);
+                       }
+               } while ((i < DA7213_SRM_CHECK_RETRIES) & (!srm_lock));
+
+               if (!srm_lock)
+                       dev_warn(codec->dev, "SRM failed to lock\n");
+
                return 0;
        case SND_SOC_DAPM_POST_PMD:
                /* Disable DAI clks if in master mode */
index 5de5c2997e0c38a786ec75381e7b040e670852fb..af75340dea63e7bced8899df91735c82eead1d1a 100644 (file)
  * Bit fields
  */
 
+/* DA7213_PLL_STATUS = 0x03 */
+#define DA7219_PLL_SRM_LOCK                                    (0x1 << 1)
+
 /* DA7213_SR = 0x22 */
 #define DA7213_SR_8000                                         (0x1 << 0)
 #define DA7213_SR_11025                                                (0x2 << 0)
 #define DA7213_PLL_INDIV_10_20_MHZ_VAL 4
 #define DA7213_PLL_INDIV_20_40_MHZ_VAL 8
 #define DA7213_PLL_INDIV_40_54_MHZ_VAL 16
+#define DA7213_SRM_CHECK_RETRIES       8
 
 enum da7213_clk_src {
        DA7213_CLKSRC_MCLK = 0,