ASoC: tegra20: spdif: Improve driver's code

- Clean up whitespaces, defines and variables.

- Remove obsolete code.

- Adhere to upstream coding style.

- Don't override returned error code.

- Replace pr_err with dev_err.

No functional changes are made by this patch. This is a minor code's
refactoring that will ease further maintenance of the driver.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20211204143725.31646-9-digetx@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/tegra/tegra20_spdif.c

@@ -23,8 +23,6 @@
 
 #include "tegra20_spdif.h"
 
-#define DRV_NAME "tegra20-spdif"
-
 static __maybe_unused int tegra20_spdif_runtime_suspend(struct device *dev)
 {
 	struct tegra20_spdif *spdif = dev_get_drvdata(dev);
@@ -52,8 +50,7 @@ static int tegra20_spdif_hw_params(struct snd_pcm_substream *substream,
 				   struct snd_pcm_hw_params *params,
 				   struct snd_soc_dai *dai)
 {
-	struct device *dev = dai->dev;
-	struct tegra20_spdif *spdif = snd_soc_dai_get_drvdata(dai);
+	struct tegra20_spdif *spdif = dev_get_drvdata(dai->dev);
 	unsigned int mask = 0, val = 0;
 	int ret, spdifclock;
 
@@ -106,7 +103,7 @@ static int tegra20_spdif_hw_params(struct snd_pcm_substream *substream,
 
 	ret = clk_set_rate(spdif->clk_spdif_out, spdifclock);
 	if (ret) {
-		dev_err(dev, "Can't set SPDIF clock rate: %d\n", ret);
+		dev_err(dai->dev, "Can't set SPDIF clock rate: %d\n", ret);
 		return ret;
 	}
 
@@ -129,7 +126,7 @@ static void tegra20_spdif_stop_playback(struct tegra20_spdif *spdif)
 static int tegra20_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
 				 struct snd_soc_dai *dai)
 {
-	struct tegra20_spdif *spdif = snd_soc_dai_get_drvdata(dai);
+	struct tegra20_spdif *spdif = dev_get_drvdata(dai->dev);
 
 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_START:
@@ -151,7 +148,7 @@ static int tegra20_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
 
 static int tegra20_spdif_probe(struct snd_soc_dai *dai)
 {
-	struct tegra20_spdif *spdif = snd_soc_dai_get_drvdata(dai);
+	struct tegra20_spdif *spdif = dev_get_drvdata(dai->dev);
 
 	dai->capture_dma_data = NULL;
 	dai->playback_dma_data = &spdif->playback_dma_data;
@@ -165,7 +162,7 @@ static const struct snd_soc_dai_ops tegra20_spdif_dai_ops = {
 };
 
 static struct snd_soc_dai_driver tegra20_spdif_dai = {
-	.name = DRV_NAME,
+	.name = "tegra20-spdif",
 	.probe = tegra20_spdif_probe,
 	.playback = {
 		.stream_name = "Playback",
@@ -179,7 +176,7 @@ static struct snd_soc_dai_driver tegra20_spdif_dai = {
 };
 
 static const struct snd_soc_component_driver tegra20_spdif_component = {
-	.name		= DRV_NAME,
+	.name = "tegra20-spdif",
 };
 
 static bool tegra20_spdif_wr_rd_reg(struct device *dev, unsigned int reg)
@@ -260,7 +257,7 @@ static const struct regmap_config tegra20_spdif_regmap_config = {
 static int tegra20_spdif_platform_probe(struct platform_device *pdev)
 {
 	struct tegra20_spdif *spdif;
-	struct resource *mem, *dmareq;
+	struct resource *mem;
 	void __iomem *regs;
 	int ret;
 
@@ -273,27 +270,19 @@ static int tegra20_spdif_platform_probe(struct platform_device *pdev)
 
 	spdif->clk_spdif_out = devm_clk_get(&pdev->dev, "out");
 	if (IS_ERR(spdif->clk_spdif_out)) {
-		pr_err("Can't retrieve spdif clock\n");
-		ret = PTR_ERR(spdif->clk_spdif_out);
-		return ret;
+		dev_err(&pdev->dev, "Could not retrieve spdif clock\n");
+		return PTR_ERR(spdif->clk_spdif_out);
 	}
 
 	regs = devm_platform_get_and_ioremap_resource(pdev, 0, &mem);
 	if (IS_ERR(regs))
 		return PTR_ERR(regs);
 
-	dmareq = platform_get_resource(pdev, IORESOURCE_DMA, 0);
-	if (!dmareq) {
-		dev_err(&pdev->dev, "No DMA resource\n");
-		return -ENODEV;
-	}
-
 	spdif->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
 					      &tegra20_spdif_regmap_config);
 	if (IS_ERR(spdif->regmap)) {
 		dev_err(&pdev->dev, "regmap init failed\n");
-		ret = PTR_ERR(spdif->regmap);
-		return ret;
+		return PTR_ERR(spdif->regmap);
 	}
 
 	spdif->playback_dma_data.addr = mem->start + TEGRA20_SPDIF_DATA_OUT;
@@ -306,7 +295,6 @@ static int tegra20_spdif_platform_probe(struct platform_device *pdev)
 					 &tegra20_spdif_dai, 1);
 	if (ret) {
 		dev_err(&pdev->dev, "Could not register DAI: %d\n", ret);
-		ret = -ENOMEM;
 		goto err_pm_disable;
 	}
 
@@ -349,14 +337,13 @@ MODULE_DEVICE_TABLE(of, tegra20_spdif_of_match);
 
 static struct platform_driver tegra20_spdif_driver = {
 	.driver = {
-		.name = DRV_NAME,
+		.name = "tegra20-spdif",
 		.pm = &tegra20_spdif_pm_ops,
 		.of_match_table = tegra20_spdif_of_match,
 	},
 	.probe = tegra20_spdif_platform_probe,
 	.remove = tegra20_spdif_platform_remove,
 };
-
 module_platform_driver(tegra20_spdif_driver);
 
 MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");