staging: iio: ad9832: use clock framework for clock reference

Previously external clock were set through platform_data struct.
Now device uses clk struct defined in include/linux/clk.h to handle
external clock source.
It also removes mclk from platform_data struct.
Signed-off-by: Marcelo Schmitt <marcelo.schmitt1@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/staging/iio/frequency/ad9832.c

@@ -7,6 +7,7 @@
 
 #include <asm/div64.h>
 
+#include <linux/clk.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/kernel.h>
@@ -95,7 +96,7 @@ struct ad9832_state {
 	struct spi_device		*spi;
 	struct regulator		*avdd;
 	struct regulator		*dvdd;
-	unsigned long			mclk;
+	struct clk			*mclk;
 	unsigned short			ctrl_fp;
 	unsigned short			ctrl_ss;
 	unsigned short			ctrl_src;
@@ -130,10 +131,10 @@ static int ad9832_write_frequency(struct ad9832_state *st,
 {
 	unsigned long regval;
 
-	if (fout > (st->mclk / 2))
+	if (fout > (clk_get_rate(st->mclk) / 2))
 		return -EINVAL;
 
-	regval = ad9832_calc_freqreg(st->mclk, fout);
+	regval = ad9832_calc_freqreg(clk_get_rate(st->mclk), fout);
 
 	st->freq_data[0] = cpu_to_be16((AD9832_CMD_FRE8BITSW << CMD_SHIFT) |
 					(addr << ADD_SHIFT) |
@@ -334,7 +335,16 @@ static int ad9832_probe(struct spi_device *spi)
 		goto error_disable_avdd;
 	}
 
-	st->mclk = pdata->mclk;
+	st->mclk = devm_clk_get(&spi->dev, "mclk");
+	if (IS_ERR(st->mclk)) {
+		ret = PTR_ERR(st->mclk);
+		goto error_disable_dvdd;
+	}
+
+	ret = clk_prepare_enable(st->mclk);
+	if (ret < 0)
+		goto error_disable_dvdd;
+
 	st->spi = spi;
 	mutex_init(&st->lock);
 
@@ -385,39 +395,41 @@ static int ad9832_probe(struct spi_device *spi)
 	ret = spi_sync(st->spi, &st->msg);
 	if (ret) {
 		dev_err(&spi->dev, "device init failed\n");
-		goto error_disable_dvdd;
+		goto error_unprepare_mclk;
 	}
 
 	ret = ad9832_write_frequency(st, AD9832_FREQ0HM, pdata->freq0);
 	if (ret)
-		goto error_disable_dvdd;
+		goto error_unprepare_mclk;
 
 	ret = ad9832_write_frequency(st, AD9832_FREQ1HM, pdata->freq1);
 	if (ret)
-		goto error_disable_dvdd;
+		goto error_unprepare_mclk;
 
 	ret = ad9832_write_phase(st, AD9832_PHASE0H, pdata->phase0);
 	if (ret)
-		goto error_disable_dvdd;
+		goto error_unprepare_mclk;
 
 	ret = ad9832_write_phase(st, AD9832_PHASE1H, pdata->phase1);
 	if (ret)
-		goto error_disable_dvdd;
+		goto error_unprepare_mclk;
 
 	ret = ad9832_write_phase(st, AD9832_PHASE2H, pdata->phase2);
 	if (ret)
-		goto error_disable_dvdd;
+		goto error_unprepare_mclk;
 
 	ret = ad9832_write_phase(st, AD9832_PHASE3H, pdata->phase3);
 	if (ret)
-		goto error_disable_dvdd;
+		goto error_unprepare_mclk;
 
 	ret = iio_device_register(indio_dev);
 	if (ret)
-		goto error_disable_dvdd;
+		goto error_unprepare_mclk;
 
 	return 0;
 
+error_unprepare_mclk:
+	clk_disable_unprepare(st->mclk);
 error_disable_dvdd:
 	regulator_disable(st->dvdd);
 error_disable_avdd:
@@ -432,6 +444,7 @@ static int ad9832_remove(struct spi_device *spi)
 	struct ad9832_state *st = iio_priv(indio_dev);
 
 	iio_device_unregister(indio_dev);
+	clk_disable_unprepare(st->mclk);
 	regulator_disable(st->dvdd);
 	regulator_disable(st->avdd);
 

drivers/staging/iio/frequency/ad9832.h

@@ -23,7 +23,6 @@
  */
 
 struct ad9832_platform_data {
-	unsigned long		mclk;
 	unsigned long		freq0;
 	unsigned long		freq1;
 	unsigned short		phase0;