ASoC: Tegra+WM8903 machine: Add device tree binding

This driver is parameterized in two ways:

a) Platform data, which supplies the set of GPIOs used by the driver.
   These GPIOs can now be parsed out of device tree.

b) Machine-specific DAPM route arrays embedded into the ASoC machine
   driver itself. Historically, the driver picks the appropriate array
   to use using machine_is_*(). The driver now requires this array to
   be parsed from device tree when instantiated through device tree,
   using the core ASoC support for this parsing.

Based on work by John Bonesio, but significantly reworked since then.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 103 insertions, 25 deletions

diff --git a/sound/soc/tegra/tegra_wm8903.c b/sound/soc/tegra/tegra_wm8903.c
index ba2d23ea6424..4677f2666300 100644
--- a/sound/soc/tegra/tegra_wm8903.c
+++ b/sound/soc/tegra/tegra_wm8903.c
@@ -34,6 +34,7 @@
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/gpio.h>
+#include <linux/of_gpio.h>
 
 #include <mach/tegra_wm8903_pdata.h>
 
@@ -59,8 +60,9 @@
 #define GPIO_HP_DET     BIT(4)
 
 struct tegra_wm8903 {
+	struct tegra_wm8903_platform_data pdata;
+	struct platform_device *pcm_dev;
 	struct tegra_asoc_utils_data util_data;
-	struct tegra_wm8903_platform_data *pdata;
 	int gpio_requested;
 };
 
@@ -160,7 +162,7 @@ static int tegra_wm8903_event_int_spk(struct snd_soc_dapm_widget *w,
 	struct snd_soc_dapm_context *dapm = w->dapm;
 	struct snd_soc_card *card = dapm->card;
 	struct tegra_wm8903 *machine = snd_soc_card_get_drvdata(card);
-	struct tegra_wm8903_platform_data *pdata = machine->pdata;
+	struct tegra_wm8903_platform_data *pdata = &machine->pdata;
 
 	if (!(machine->gpio_requested & GPIO_SPKR_EN))
 		return 0;
@@ -177,7 +179,7 @@ static int tegra_wm8903_event_hp(struct snd_soc_dapm_widget *w,
 	struct snd_soc_dapm_context *dapm = w->dapm;
 	struct snd_soc_card *card = dapm->card;
 	struct tegra_wm8903 *machine = snd_soc_card_get_drvdata(card);
-	struct tegra_wm8903_platform_data *pdata = machine->pdata;
+	struct tegra_wm8903_platform_data *pdata = &machine->pdata;
 
 	if (!(machine->gpio_requested & GPIO_HP_MUTE))
 		return 0;
@@ -246,9 +248,36 @@ static int tegra_wm8903_init(struct snd_soc_pcm_runtime *rtd)
 	struct snd_soc_dapm_context *dapm = &codec->dapm;
 	struct snd_soc_card *card = codec->card;
 	struct tegra_wm8903 *machine = snd_soc_card_get_drvdata(card);
-	struct tegra_wm8903_platform_data *pdata = machine->pdata;
+	struct tegra_wm8903_platform_data *pdata = &machine->pdata;
+	struct device_node *np = card->dev->of_node;
 	int ret;
 
+	if (card->dev->platform_data) {
+		memcpy(pdata, card->dev->platform_data, sizeof(*pdata));
+	} else if (np) {
+		/*
+		 * This part must be in init() rather than probe() in order to
+		 * guarantee that the WM8903 has been probed, and hence its
+		 * GPIO controller registered, which is a pre-condition for
+		 * of_get_named_gpio() to be able to map the phandles in the
+		 * properties to the controller node. Given this, all
+		 * pdata handling is in init() for consistency.
+		 */
+		pdata->gpio_spkr_en = of_get_named_gpio(np,
+						"nvidia,spkr-en-gpios", 0);
+		pdata->gpio_hp_mute = of_get_named_gpio(np,
+						"nvidia,hp-mute-gpios", 0);
+		pdata->gpio_hp_det = of_get_named_gpio(np,
+						"nvidia,hp-det-gpios", 0);
+		pdata->gpio_int_mic_en = of_get_named_gpio(np,
+						"nvidia,int-mic-en-gpios", 0);
+		pdata->gpio_ext_mic_en = of_get_named_gpio(np,
+						"nvidia,ext-mic-en-gpios", 0);
+	} else {
+		dev_err(card->dev, "No platform data supplied\n");
+		return -EINVAL;
+	}
+
 	if (gpio_is_valid(pdata->gpio_spkr_en)) {
 		ret = gpio_request(pdata->gpio_spkr_en, "spkr_en");
 		if (ret) {
@@ -348,11 +377,9 @@ static __devinit int tegra_wm8903_driver_probe(struct platform_device *pdev)
 {
 	struct snd_soc_card *card = &snd_soc_tegra_wm8903;
 	struct tegra_wm8903 *machine;
-	struct tegra_wm8903_platform_data *pdata;
 	int ret;
 
-	pdata = pdev->dev.platform_data;
-	if (!pdata) {
+	if (!pdev->dev.platform_data && !pdev->dev.of_node) {
 		dev_err(&pdev->dev, "No platform data supplied\n");
 		return -EINVAL;
 	}
@@ -364,31 +391,70 @@ static __devinit int tegra_wm8903_driver_probe(struct platform_device *pdev)
 		ret = -ENOMEM;
 		goto err;
 	}
-
-	machine->pdata = pdata;
-
-	ret = tegra_asoc_utils_init(&machine->util_data, &pdev->dev);
-	if (ret)
-		goto err;
+	machine->pcm_dev = ERR_PTR(-EINVAL);
 
 	card->dev = &pdev->dev;
 	platform_set_drvdata(pdev, card);
 	snd_soc_card_set_drvdata(card, machine);
 
-	if (machine_is_harmony()) {
-		card->dapm_routes = harmony_audio_map;
-		card->num_dapm_routes = ARRAY_SIZE(harmony_audio_map);
-	} else if (machine_is_seaboard()) {
-		card->dapm_routes = seaboard_audio_map;
-		card->num_dapm_routes = ARRAY_SIZE(seaboard_audio_map);
-	} else if (machine_is_kaen()) {
-		card->dapm_routes = kaen_audio_map;
-		card->num_dapm_routes = ARRAY_SIZE(kaen_audio_map);
+	if (pdev->dev.of_node) {
+		ret = snd_soc_of_parse_card_name(card, "nvidia,model");
+		if (ret)
+			goto err;
+
+		ret = snd_soc_of_parse_audio_routing(card,
+						     "nvidia,audio-routing");
+		if (ret)
+			goto err;
+
+		tegra_wm8903_dai.codec_name = NULL;
+		tegra_wm8903_dai.codec_of_node = of_parse_phandle(
+				pdev->dev.of_node, "nvidia,audio-codec", 0);
+		if (!tegra_wm8903_dai.codec_of_node) {
+			dev_err(&pdev->dev,
+				"Property 'nvidia,audio-codec' missing or invalid\n");
+			ret = -EINVAL;
+			goto err;
+		}
+
+		tegra_wm8903_dai.cpu_dai_name = NULL;
+		tegra_wm8903_dai.cpu_dai_of_node = of_parse_phandle(
+				pdev->dev.of_node, "nvidia,i2s-controller", 0);
+		if (!tegra_wm8903_dai.cpu_dai_of_node) {
+			dev_err(&pdev->dev,
+				"Property 'nvidia,i2s-controller' missing or invalid\n");
+			ret = -EINVAL;
+			goto err;
+		}
+
+		machine->pcm_dev = platform_device_register_simple(
+					"tegra-pcm-audio", -1, NULL, 0);
+		if (IS_ERR(machine->pcm_dev)) {
+			dev_err(&pdev->dev,
+				"Can't instantiate tegra-pcm-audio\n");
+			ret = PTR_ERR(machine->pcm_dev);
+			goto err;
+		}
 	} else {
-		card->dapm_routes = aebl_audio_map;
-		card->num_dapm_routes = ARRAY_SIZE(aebl_audio_map);
+		if (machine_is_harmony()) {
+			card->dapm_routes = harmony_audio_map;
+			card->num_dapm_routes = ARRAY_SIZE(harmony_audio_map);
+		} else if (machine_is_seaboard()) {
+			card->dapm_routes = seaboard_audio_map;
+			card->num_dapm_routes = ARRAY_SIZE(seaboard_audio_map);
+		} else if (machine_is_kaen()) {
+			card->dapm_routes = kaen_audio_map;
+			card->num_dapm_routes = ARRAY_SIZE(kaen_audio_map);
+		} else {
+			card->dapm_routes = aebl_audio_map;
+			card->num_dapm_routes = ARRAY_SIZE(aebl_audio_map);
+		}
 	}
 
+	ret = tegra_asoc_utils_init(&machine->util_data, &pdev->dev);
+	if (ret)
+		goto err_unregister;
+
 	ret = snd_soc_register_card(card);
 	if (ret) {
 		dev_err(&pdev->dev, "snd_soc_register_card failed (%d)\n",
@@ -400,6 +466,9 @@ static __devinit int tegra_wm8903_driver_probe(struct platform_device *pdev)
 
 err_fini_utils:
 	tegra_asoc_utils_fini(&machine->util_data);
+err_unregister:
+	if (!IS_ERR(machine->pcm_dev))
+		platform_device_unregister(machine->pcm_dev);
 err:
 	return ret;
 }
@@ -408,7 +477,7 @@ static int __devexit tegra_wm8903_driver_remove(struct platform_device *pdev)
 {
 	struct snd_soc_card *card = platform_get_drvdata(pdev);
 	struct tegra_wm8903 *machine = snd_soc_card_get_drvdata(card);
-	struct tegra_wm8903_platform_data *pdata = machine->pdata;
+	struct tegra_wm8903_platform_data *pdata = &machine->pdata;
 
 	if (machine->gpio_requested & GPIO_HP_DET)
 		snd_soc_jack_free_gpios(&tegra_wm8903_hp_jack,
@@ -427,15 +496,23 @@ static int __devexit tegra_wm8903_driver_remove(struct platform_device *pdev)
 	snd_soc_unregister_card(card);
 
 	tegra_asoc_utils_fini(&machine->util_data);
+	if (!IS_ERR(machine->pcm_dev))
+		platform_device_unregister(machine->pcm_dev);
 
 	return 0;
 }
 
+static const struct of_device_id tegra_wm8903_of_match[] __devinitconst = {
+	{ .compatible = "nvidia,tegra-audio-wm8903", },
+	{},
+};
+
 static struct platform_driver tegra_wm8903_driver = {
 	.driver = {
 		.name = DRV_NAME,
 		.owner = THIS_MODULE,
 		.pm = &snd_soc_pm_ops,
+		.of_match_table = tegra_wm8903_of_match,
 	},
 	.probe = tegra_wm8903_driver_probe,
 	.remove = __devexit_p(tegra_wm8903_driver_remove),
@@ -446,3 +523,4 @@ MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");
 MODULE_DESCRIPTION("Tegra+WM8903 machine ASoC driver");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:" DRV_NAME);
+MODULE_DEVICE_TABLE(of, tegra_wm8903_of_match);