iio: adc: ad7192: convert to device-managed functions

With the devm_ad_sd_setup_buffer_and_trigger() helper, it's a bit easier
now to convert the probe of the AD7192 driver to use device-managed
functions.

The regulators and the mclk requires devm_add_action_or_reset() callbacks
though.
Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Link: https://lore.kernel.org/r/20210513120752.90074-11-aardelean@deviqon.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/adc/ad7192.c

@@ -908,6 +908,16 @@ static int ad7192_channels_config(struct iio_dev *indio_dev)
 	return 0;
 }
 
+static void ad7192_reg_disable(void *reg)
+{
+	regulator_disable(reg);
+}
+
+static void ad7192_clk_disable(void *clk)
+{
+	clk_disable_unprepare(clk);
+}
+
 static int ad7192_probe(struct spi_device *spi)
 {
 	struct ad7192_state *st;
@@ -937,33 +947,38 @@ static int ad7192_probe(struct spi_device *spi)
 		return ret;
 	}
 
+	ret = devm_add_action_or_reset(&spi->dev, ad7192_reg_disable, st->avdd);
+	if (ret)
+		return ret;
+
 	st->dvdd = devm_regulator_get(&spi->dev, "dvdd");
-	if (IS_ERR(st->dvdd)) {
-		ret = PTR_ERR(st->dvdd);
-		goto error_disable_avdd;
-	}
+	if (IS_ERR(st->dvdd))
+		return PTR_ERR(st->dvdd);
 
 	ret = regulator_enable(st->dvdd);
 	if (ret) {
 		dev_err(&spi->dev, "Failed to enable specified DVdd supply\n");
-		goto error_disable_avdd;
+		return ret;
 	}
 
+	ret = devm_add_action_or_reset(&spi->dev, ad7192_reg_disable, st->dvdd);
+	if (ret)
+		return ret;
+
 	ret = regulator_get_voltage(st->avdd);
 	if (ret < 0) {
 		dev_err(&spi->dev, "Device tree error, reference voltage undefined\n");
-		goto error_disable_avdd;
+		return ret;
 	}
 	st->int_vref_mv = ret / 1000;
 
-	spi_set_drvdata(spi, indio_dev);
 	st->chip_info = of_device_get_match_data(&spi->dev);
 	indio_dev->name = st->chip_info->name;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
 	ret = ad7192_channels_config(indio_dev);
 	if (ret < 0)
-		goto error_disable_dvdd;
+		return ret;
 
 	if (st->chip_info->chip_id == CHIPID_AD7195)
 		indio_dev->info = &ad7195_info;
@@ -972,17 +987,15 @@ static int ad7192_probe(struct spi_device *spi)
 
 	ad_sd_init(&st->sd, indio_dev, spi, &ad7192_sigma_delta_info);
 
-	ret = ad_sd_setup_buffer_and_trigger(indio_dev);
+	ret = devm_ad_sd_setup_buffer_and_trigger(&spi->dev, indio_dev);
 	if (ret)
-		goto error_disable_dvdd;
+		return ret;
 
 	st->fclk = AD7192_INT_FREQ_MHZ;
 
 	st->mclk = devm_clk_get_optional(&spi->dev, "mclk");
-	if (IS_ERR(st->mclk)) {
-		ret = PTR_ERR(st->mclk);
-		goto error_remove_trigger;
-	}
+	if (IS_ERR(st->mclk))
+		return PTR_ERR(st->mclk);
 
 	st->clock_sel = ad7192_of_clock_select(st);
 
@@ -990,55 +1003,26 @@ static int ad7192_probe(struct spi_device *spi)
 	    st->clock_sel == AD7192_CLK_EXT_MCLK2) {
 		ret = clk_prepare_enable(st->mclk);
 		if (ret < 0)
-			goto error_remove_trigger;
+			return ret;
+
+		ret = devm_add_action_or_reset(&spi->dev, ad7192_clk_disable,
+					       st->mclk);
+		if (ret)
+			return ret;
 
 		st->fclk = clk_get_rate(st->mclk);
 		if (!ad7192_valid_external_frequency(st->fclk)) {
-			ret = -EINVAL;
 			dev_err(&spi->dev,
 				"External clock frequency out of bounds\n");
-			goto error_disable_clk;
+			return -EINVAL;
 		}
 	}
 
 	ret = ad7192_setup(st, spi->dev.of_node);
 	if (ret)
-		goto error_disable_clk;
-
-	ret = iio_device_register(indio_dev);
-	if (ret < 0)
-		goto error_disable_clk;
-	return 0;
-
-error_disable_clk:
-	if (st->clock_sel == AD7192_CLK_EXT_MCLK1_2 ||
-	    st->clock_sel == AD7192_CLK_EXT_MCLK2)
-		clk_disable_unprepare(st->mclk);
-error_remove_trigger:
-	ad_sd_cleanup_buffer_and_trigger(indio_dev);
-error_disable_dvdd:
-	regulator_disable(st->dvdd);
-error_disable_avdd:
-	regulator_disable(st->avdd);
-
 		return ret;
-}
-
-static int ad7192_remove(struct spi_device *spi)
-{
-	struct iio_dev *indio_dev = spi_get_drvdata(spi);
-	struct ad7192_state *st = iio_priv(indio_dev);
 
-	iio_device_unregister(indio_dev);
-	if (st->clock_sel == AD7192_CLK_EXT_MCLK1_2 ||
-	    st->clock_sel == AD7192_CLK_EXT_MCLK2)
-		clk_disable_unprepare(st->mclk);
-	ad_sd_cleanup_buffer_and_trigger(indio_dev);
-
-	regulator_disable(st->dvdd);
-	regulator_disable(st->avdd);
-
-	return 0;
+	return devm_iio_device_register(&spi->dev, indio_dev);
 }
 
 static const struct of_device_id ad7192_of_match[] = {
@@ -1056,7 +1040,6 @@ static struct spi_driver ad7192_driver = {
 		.of_match_table = ad7192_of_match,
 	},
 	.probe		= ad7192_probe,
-	.remove		= ad7192_remove,
 };
 module_spi_driver(ad7192_driver);