sound: tegra: Add a sound driver

Add a sound driver for tegra devices. This connects the audio hub, I2S
controller and audio codec to allow sound output.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/drivers/sound/tegra_sound.c b/drivers/sound/tegra_sound.c
new file mode 100644
index 0000000..7c2ed53
--- /dev/null
+++ b/drivers/sound/tegra_sound.c
@@ -0,0 +1,100 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2018 Google, LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#define LOG_CATEGORY UCLASS_I2S
+
+#include <common.h>
+#include <audio_codec.h>
+#include <dm.h>
+#include <i2s.h>
+#include <misc.h>
+#include <sound.h>
+#include <asm/gpio.h>
+#include "tegra_i2s_priv.h"
+
+static int tegra_sound_setup(struct udevice *dev)
+{
+	struct sound_uc_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct i2s_uc_priv *i2c_priv = dev_get_uclass_priv(uc_priv->i2s);
+	int ret;
+
+	if (uc_priv->setup_done)
+		return -EALREADY;
+	ret = audio_codec_set_params(uc_priv->codec, i2c_priv->id,
+				     i2c_priv->samplingrate,
+				     i2c_priv->samplingrate * i2c_priv->rfs,
+				     i2c_priv->bitspersample,
+				     i2c_priv->channels);
+	if (ret)
+		return ret;
+	uc_priv->setup_done = true;
+
+	return 0;
+}
+
+static int tegra_sound_play(struct udevice *dev, void *data, uint data_size)
+{
+	struct sound_uc_priv *uc_priv = dev_get_uclass_priv(dev);
+
+	return i2s_tx_data(uc_priv->i2s, data, data_size);
+}
+
+static int tegra_sound_probe(struct udevice *dev)
+{
+	struct sound_uc_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct gpio_desc en_gpio;
+	struct udevice *ahub;
+	int ret;
+
+	ret = gpio_request_by_name(dev, "codec-enable-gpio", 0, &en_gpio,
+				   GPIOD_IS_OUT | GPIOD_IS_OUT_ACTIVE);
+
+	ret = uclass_get_device_by_phandle(UCLASS_AUDIO_CODEC, dev,
+					   "nvidia,audio-codec",
+					   &uc_priv->codec);
+	if (ret) {
+		log_debug("Failed to probe audio codec\n");
+		return ret;
+	}
+	ret = uclass_get_device_by_phandle(UCLASS_I2S, dev,
+					   "nvidia,i2s-controller",
+					   &uc_priv->i2s);
+	if (ret) {
+		log_debug("Cannot find i2s: %d\n", ret);
+		return ret;
+	}
+
+	/* Set up the audio hub, telling it the currect i2s to use */
+	ahub = dev_get_parent(uc_priv->i2s);
+	ret = misc_ioctl(ahub, AHUB_MISCOP_SET_I2S, &uc_priv->i2s);
+	if (ret) {
+		log_debug("Cannot set i2c: %d\n", ret);
+		return ret;
+	}
+
+	log_debug("Probed sound '%s' with codec '%s' and i2s '%s'\n", dev->name,
+		  uc_priv->codec->name, uc_priv->i2s->name);
+
+	return 0;
+}
+
+static const struct sound_ops tegra_sound_ops = {
+	.setup	= tegra_sound_setup,
+	.play	= tegra_sound_play,
+};
+
+static const struct udevice_id tegra_sound_ids[] = {
+	{ .compatible = "nvidia,tegra-audio-max98090-nyan-big" },
+	{ }
+};
+
+U_BOOT_DRIVER(tegra_sound) = {
+	.name		= "tegra_sound",
+	.id		= UCLASS_SOUND,
+	.of_match	= tegra_sound_ids,
+	.probe		= tegra_sound_probe,
+	.ops		= &tegra_sound_ops,
+};