ASoC: max98090: Add master clock handling

If master clock is provided through device tree, then update
the master clock frequency during set_sysclk.

Documentation has been updated to reflect the change.

Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

diff --git a/Documentation/devicetree/bindings/sound/max98090.txt b/Documentation/devicetree/bindings/sound/max98090.txt
index e4c8b36..a5e63fa 100644 (file)
--- a/Documentation/devicetree/bindings/sound/max98090.txt
+++ b/Documentation/devicetree/bindings/sound/max98090.txt
@@ -10,6 +10,12 @@ Required properties:
 
 - interrupts : The CODEC's interrupt output.
 
+Optional properties:
+
+- clocks: The phandle of the master clock to the CODEC
+
+- clock-names: Should be "mclk"
+
 Pins on the device (for linking into audio routes):
 
   * MIC1

diff --git a/sound/soc/codecs/max98090.c b/sound/soc/codecs/max98090.c
index 4ee1f88..8857be7 100644 (file)
--- a/sound/soc/codecs/max98090.c
+++ b/sound/soc/codecs/max98090.c
@@ -16,6 +16,7 @@
 #include <linux/regmap.h>
 #include <linux/slab.h>
 #include <linux/acpi.h>
+#include <linux/clk.h>
 #include <sound/jack.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
@@ -1798,6 +1799,19 @@ static int max98090_set_bias_level(struct snd_soc_codec *codec,
                break;
 
        case SND_SOC_BIAS_PREPARE:
+               /*
+                * SND_SOC_BIAS_PREPARE is called while preparing for a
+                * transition to ON or away from ON. If current bias_level
+                * is SND_SOC_BIAS_ON, then it is preparing for a transition
+                * away from ON. Disable the clock in that case, otherwise
+                * enable it.
+                */
+               if (!IS_ERR(max98090->mclk)) {
+                       if (codec->dapm.bias_level == SND_SOC_BIAS_ON)
+                               clk_disable_unprepare(max98090->mclk);
+                       else
+                               clk_prepare_enable(max98090->mclk);
+               }
                break;
 
        case SND_SOC_BIAS_STANDBY:
@@ -1927,6 +1941,11 @@ static int max98090_dai_set_sysclk(struct snd_soc_dai *dai,
        if (freq == max98090->sysclk)
                return 0;
 
+       if (!IS_ERR(max98090->mclk)) {
+               freq = clk_round_rate(max98090->mclk, freq);
+               clk_set_rate(max98090->mclk, freq);
+       }
+
        /* Setup clocks for slave mode, and using the PLL
         * PSCLK = 0x01 (when master clk is 10MHz to 20MHz)
         *               0x02 (when master clk is 20MHz to 40MHz)..
@@ -2211,6 +2230,10 @@ static int max98090_probe(struct snd_soc_codec *codec)
 
        dev_dbg(codec->dev, "max98090_probe\n");
 
+       max98090->mclk = devm_clk_get(codec->dev, "mclk");
+       if (PTR_ERR(max98090->mclk) == -EPROBE_DEFER)
+               return -EPROBE_DEFER;
+
        max98090->codec = codec;
 
        /* Reset the codec, the DSP core, and disable all interrupts */

diff --git a/sound/soc/codecs/max98090.h b/sound/soc/codecs/max98090.h
index 5a3c8d0..cf1b606 100644 (file)
--- a/sound/soc/codecs/max98090.h
+++ b/sound/soc/codecs/max98090.h
@@ -1524,6 +1524,7 @@ struct max98090_priv {
        struct snd_soc_codec *codec;
        enum max98090_type devtype;
        struct max98090_pdata *pdata;
+       struct clk *mclk;
        unsigned int sysclk;
        unsigned int bclk;
        unsigned int lrclk;