[PATCH v2 1/2] ASoC: codecs: nau8824: Add master clock handling

[Maxim Kochetkov <fido_max@xxxxxxxx>]

Use master clock "mclk" if provided through device tree.

Signed-off-by: Maxim Kochetkov <fido_max@xxxxxxxx>
---
 sound/soc/codecs/nau8824.c | 21 +++++++++++++++++++--
 sound/soc/codecs/nau8824.h |  1 +
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/sound/soc/codecs/nau8824.c b/sound/soc/codecs/nau8824.c
index f92b95b21cae..7153b746f4b1 100644
--- a/sound/soc/codecs/nau8824.c
+++ b/sound/soc/codecs/nau8824.c
@@ -520,8 +520,15 @@ static int system_clock_control(struct snd_soc_dapm_widget *w,
 		} else {
 			nau8824_config_sysclk(nau8824, NAU8824_CLK_DIS, 0);
 		}
+
+		if (!IS_ERR(nau8824->mclk))
+			clk_disable_unprepare(nau8824->mclk);
 	} else {
 		dev_dbg(nau8824->dev, "system clock control : POWER ON\n");
+
+		if (!IS_ERR(nau8824->mclk))
+			clk_prepare_enable(nau8824->mclk);
+
 		/* Check the clock source setting is proper or not
 		 * no matter the source is from FLL or MCLK.
 		 */
@@ -563,16 +570,22 @@ static int dmic_clock_control(struct snd_soc_dapm_widget *w,
 	struct snd_soc_component *component = snd_soc_dapm_to_component(w->dapm);
 	struct nau8824 *nau8824 = snd_soc_component_get_drvdata(component);
 	int src;
+	unsigned int freq;
+
+	if (!IS_ERR(nau8824->mclk))
+		freq = clk_get_rate(nau8824->mclk);
+	else
+		freq = nau8824->fs * 256;
 
 	/* The DMIC clock is gotten from system clock (256fs) divided by
 	 * DMIC_SRC (1, 2, 4, 8, 16, 32). The clock has to be equal or
 	 * less than 3.072 MHz.
 	 */
 	for (src = 0; src < 5; src++) {
-		if ((0x1 << (8 - src)) * nau8824->fs <= DMIC_CLK)
+		if (freq / (0x1 << src) <= DMIC_CLK)
 			break;
 	}
-	dev_dbg(nau8824->dev, "dmic src %d for mclk %d\n", src, nau8824->fs * 256);
+	dev_dbg(nau8824->dev, "dmic src %d for mclk %d\n", src, freq);
 	regmap_update_bits(nau8824->regmap, NAU8824_REG_CLK_DIVIDER,
 		NAU8824_CLK_DMIC_SRC_MASK, (src << NAU8824_CLK_DMIC_SRC_SFT));
 
@@ -1871,6 +1884,10 @@ static int nau8824_read_device_properties(struct device *dev,
 	if (ret)
 		nau8824->jack_eject_debounce = 1;
 
+	nau8824->mclk = devm_clk_get(dev, "mclk");
+	if (PTR_ERR(nau8824->mclk) == -EPROBE_DEFER)
+		return -EPROBE_DEFER;
+
 	return 0;
 }
 
diff --git a/sound/soc/codecs/nau8824.h b/sound/soc/codecs/nau8824.h
index 5fcfc43dfc85..d8e19515133c 100644
--- a/sound/soc/codecs/nau8824.h
+++ b/sound/soc/codecs/nau8824.h
@@ -434,6 +434,7 @@ struct nau8824 {
 	struct snd_soc_jack *jack;
 	struct work_struct jdet_work;
 	struct semaphore jd_sem;
+	struct clk *mclk;
 	int fs;
 	int irq;
 	int resume_lock;
-- 
2.45.2