[PATCH v1 3/5] ASoC: codec: pcm1681: Enable system clock before regmap access

[Mohammad Rafi Shaik]

The PCM1681 DAC requires the SCK (system clock) input to be
present for proper device operation. On platforms where SCK
is provided by a controllable clock source, register accesses
over I2C may fail when the clock is not enabled.

Add optional clock support to the PCM1681 driver by acquiring
the "sck" clock, enabling it during probe, and registering a
managed cleanup action to disable it during device removal or
probe failure.

This allows platforms to model the PCM1681 system clock through
the common clock framework and ensures the device is operational
before regmap initialization and register accesses occur.

Signed-off-by: Mohammad Rafi Shaik <mohammad.rafi.shaik@xxxxxxxxxxxxxxxx>
---
 sound/soc/codecs/pcm1681.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/sound/soc/codecs/pcm1681.c b/sound/soc/codecs/pcm1681.c
index 60fdbe5c4e05..cfe549176d14 100644
--- a/sound/soc/codecs/pcm1681.c
+++ b/sound/soc/codecs/pcm1681.c
@@ -12,6 +12,7 @@
 #include <linux/i2c.h>
 #include <linux/regmap.h>
 #include <linux/of.h>
+#include <linux/clk.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 #include <sound/soc.h>
@@ -74,6 +75,7 @@ struct pcm1681_private {
 	unsigned int deemph;
 	/* Current rate for deemphasis control */
 	unsigned int rate;
+	struct clk *sclk;
 };
 
 static const int pcm1681_deemph[] = { 44100, 48000, 32000 };
@@ -311,6 +313,22 @@ static int pcm1681_i2c_probe(struct i2c_client *client)
 	if (!priv)
 		return -ENOMEM;
 
+	priv->sclk = devm_clk_get_optional(&client->dev, "sck");
+	if (IS_ERR(priv->sclk))
+		return dev_err_probe(&client->dev, PTR_ERR(priv->sclk),
+				     "Failed to get sck\n");
+
+	ret = clk_prepare_enable(priv->sclk);
+	if (ret)
+		return dev_err_probe(&client->dev, ret,
+				     "Failed to enable sck\n");
+
+	ret = devm_add_action_or_reset(&client->dev,
+				       (void (*)(void *))clk_disable_unprepare,
+				       priv->sclk);
+	if (ret)
+		return ret;
+
 	priv->regmap = devm_regmap_init_i2c(client, &pcm1681_regmap);
 	if (IS_ERR(priv->regmap)) {
 		ret = PTR_ERR(priv->regmap);

-- 
2.34.1