drm/tegra: hdmi: Register audio CODEC on Tegra20

Tegra20 SoC supports only S/PDIF source for HDMI audio. Register ASoC HDMI
S/PDIF CODEC for Tegra20, it will be linked with the S/PDIF CPU DAI.
Signed-off-by: NDmitry Osipenko <digetx@gmail.com>
Signed-off-by: NThierry Reding <treding@nvidia.com>

drivers/gpu/drm/tegra/Kconfig

@@ -12,6 +12,9 @@ config DRM_TEGRA
 	select INTERCONNECT
 	select IOMMU_IOVA
 	select CEC_CORE if CEC_NOTIFIER
+	select SND_SIMPLE_CARD if SND_SOC_TEGRA20_SPDIF
+	select SND_SOC_HDMI_CODEC if SND_SOC_TEGRA20_SPDIF
+	select SND_AUDIO_GRAPH_CARD if SND_SOC_TEGRA20_SPDIF
 	help
 	  Choose this option if you have an NVIDIA Tegra SoC.
 

drivers/gpu/drm/tegra/hdmi.c

@@ -15,6 +15,8 @@
 #include <linux/regulator/consumer.h>
 #include <linux/reset.h>
 
+#include <sound/hdmi-codec.h>
+
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_crtc.h>
 #include <drm/drm_debugfs.h>
@@ -78,6 +80,9 @@ struct tegra_hdmi {
 	bool dvi;
 
 	struct drm_info_list *debugfs_files;
+
+	struct platform_device *audio_pdev;
+	struct mutex audio_lock;
 };
 
 static inline struct tegra_hdmi *
@@ -360,6 +365,18 @@ static const struct tmds_config tegra124_tmds_config[] = {
 	},
 };
 
+static void tegra_hdmi_audio_lock(struct tegra_hdmi *hdmi)
+{
+	mutex_lock(&hdmi->audio_lock);
+	disable_irq(hdmi->irq);
+}
+
+static void tegra_hdmi_audio_unlock(struct tegra_hdmi *hdmi)
+{
+	enable_irq(hdmi->irq);
+	mutex_unlock(&hdmi->audio_lock);
+}
+
 static int
 tegra_hdmi_get_audio_config(unsigned int audio_freq, unsigned int pix_clock,
 			    struct tegra_hdmi_audio_config *config)
@@ -829,6 +846,23 @@ static void tegra_hdmi_setup_tmds(struct tegra_hdmi *hdmi,
 				  HDMI_NV_PDISP_SOR_IO_PEAK_CURRENT);
 }
 
+static int tegra_hdmi_reconfigure_audio(struct tegra_hdmi *hdmi)
+{
+	int err;
+
+	err = tegra_hdmi_setup_audio(hdmi);
+	if (err < 0) {
+		tegra_hdmi_disable_audio_infoframe(hdmi);
+		tegra_hdmi_disable_audio(hdmi);
+	} else {
+		tegra_hdmi_setup_audio_infoframe(hdmi);
+		tegra_hdmi_enable_audio_infoframe(hdmi);
+		tegra_hdmi_enable_audio(hdmi);
+	}
+
+	return err;
+}
+
 static bool tegra_output_is_hdmi(struct tegra_output *output)
 {
 	struct edid *edid;
@@ -1135,6 +1169,8 @@ static void tegra_hdmi_encoder_disable(struct drm_encoder *encoder)
 	u32 value;
 	int err;
 
+	tegra_hdmi_audio_lock(hdmi);
+
 	/*
 	 * The following accesses registers of the display controller, so make
 	 * sure it's only executed when the output is attached to one.
@@ -1159,6 +1195,10 @@ static void tegra_hdmi_encoder_disable(struct drm_encoder *encoder)
 	tegra_hdmi_writel(hdmi, 0, HDMI_NV_PDISP_INT_ENABLE);
 	tegra_hdmi_writel(hdmi, 0, HDMI_NV_PDISP_INT_MASK);
 
+	hdmi->pixel_clock = 0;
+
+	tegra_hdmi_audio_unlock(hdmi);
+
 	err = host1x_client_suspend(&hdmi->client);
 	if (err < 0)
 		dev_err(hdmi->dev, "failed to suspend: %d\n", err);
@@ -1182,6 +1222,8 @@ static void tegra_hdmi_encoder_enable(struct drm_encoder *encoder)
 		return;
 	}
 
+	tegra_hdmi_audio_lock(hdmi);
+
 	/*
 	 * Enable and unmask the HDA codec SCRATCH0 register interrupt. This
 	 * is used for interoperability between the HDA codec driver and the
@@ -1387,6 +1429,8 @@ static void tegra_hdmi_encoder_enable(struct drm_encoder *encoder)
 	}
 
 	/* TODO: add HDCP support */
+
+	tegra_hdmi_audio_unlock(hdmi);
 }
 
 static int
@@ -1416,6 +1460,91 @@ static const struct drm_encoder_helper_funcs tegra_hdmi_encoder_helper_funcs = {
 	.atomic_check = tegra_hdmi_encoder_atomic_check,
 };
 
+static int tegra_hdmi_hw_params(struct device *dev, void *data,
+				struct hdmi_codec_daifmt *fmt,
+				struct hdmi_codec_params *hparms)
+{
+	struct tegra_hdmi *hdmi = data;
+	int ret = 0;
+
+	tegra_hdmi_audio_lock(hdmi);
+
+	hdmi->format.sample_rate = hparms->sample_rate;
+	hdmi->format.channels = hparms->channels;
+
+	if (hdmi->pixel_clock && !hdmi->dvi)
+		ret = tegra_hdmi_reconfigure_audio(hdmi);
+
+	tegra_hdmi_audio_unlock(hdmi);
+
+	return ret;
+}
+
+static int tegra_hdmi_audio_startup(struct device *dev, void *data)
+{
+	struct tegra_hdmi *hdmi = data;
+	int ret;
+
+	ret = host1x_client_resume(&hdmi->client);
+	if (ret < 0)
+		dev_err(hdmi->dev, "failed to resume: %d\n", ret);
+
+	return ret;
+}
+
+static void tegra_hdmi_audio_shutdown(struct device *dev, void *data)
+{
+	struct tegra_hdmi *hdmi = data;
+	int ret;
+
+	tegra_hdmi_audio_lock(hdmi);
+
+	hdmi->format.sample_rate = 0;
+	hdmi->format.channels = 0;
+
+	tegra_hdmi_audio_unlock(hdmi);
+
+	ret = host1x_client_suspend(&hdmi->client);
+	if (ret < 0)
+		dev_err(hdmi->dev, "failed to suspend: %d\n", ret);
+}
+
+static const struct hdmi_codec_ops tegra_hdmi_codec_ops = {
+	.hw_params = tegra_hdmi_hw_params,
+	.audio_startup = tegra_hdmi_audio_startup,
+	.audio_shutdown = tegra_hdmi_audio_shutdown,
+};
+
+static int tegra_hdmi_codec_register(struct tegra_hdmi *hdmi)
+{
+	struct hdmi_codec_pdata codec_data = {};
+
+	if (hdmi->config->has_hda)
+		return 0;
+
+	codec_data.ops = &tegra_hdmi_codec_ops;
+	codec_data.data = hdmi;
+	codec_data.spdif = 1;
+
+	hdmi->audio_pdev = platform_device_register_data(hdmi->dev,
+							 HDMI_CODEC_DRV_NAME,
+							 PLATFORM_DEVID_AUTO,
+							 &codec_data,
+							 sizeof(codec_data));
+	if (IS_ERR(hdmi->audio_pdev))
+		return PTR_ERR(hdmi->audio_pdev);
+
+	hdmi->format.channels = 2;
+
+	return 0;
+}
+
+static void tegra_hdmi_codec_unregister(struct tegra_hdmi *hdmi)
+{
+	if (hdmi->audio_pdev)
+		platform_device_unregister(hdmi->audio_pdev);
+}
+
 static int tegra_hdmi_init(struct host1x_client *client)
 {
 	struct tegra_hdmi *hdmi = host1x_client_to_hdmi(client);
@@ -1468,8 +1597,16 @@ static int tegra_hdmi_init(struct host1x_client *client)
 		goto disable_pll;
 	}
 
+	err = tegra_hdmi_codec_register(hdmi);
+	if (err < 0) {
+		dev_err(hdmi->dev, "failed to register audio codec: %d\n", err);
+		goto disable_vdd;
+	}
+
 	return 0;
 
+disable_vdd:
+	regulator_disable(hdmi->vdd);
 disable_pll:
 	regulator_disable(hdmi->pll);
 disable_hdmi:
@@ -1484,6 +1621,8 @@ static int tegra_hdmi_exit(struct host1x_client *client)
 {
 	struct tegra_hdmi *hdmi = host1x_client_to_hdmi(client);
 
+	tegra_hdmi_codec_unregister(hdmi);
+
 	tegra_output_exit(&hdmi->output);
 
 	regulator_disable(hdmi->vdd);
@@ -1608,7 +1747,6 @@ static irqreturn_t tegra_hdmi_irq(int irq, void *data)
 {
 	struct tegra_hdmi *hdmi = data;
 	u32 value;
-	int err;
 
 	value = tegra_hdmi_readl(hdmi, HDMI_NV_PDISP_INT_STATUS);
 	tegra_hdmi_writel(hdmi, value, HDMI_NV_PDISP_INT_STATUS);
@@ -1623,16 +1761,7 @@ static irqreturn_t tegra_hdmi_irq(int irq, void *data)
 			format = value & SOR_AUDIO_HDA_CODEC_SCRATCH0_FMT_MASK;
 
 			tegra_hda_parse_format(format, &hdmi->format);
-
-			err = tegra_hdmi_setup_audio(hdmi);
-			if (err < 0) {
-				tegra_hdmi_disable_audio_infoframe(hdmi);
-				tegra_hdmi_disable_audio(hdmi);
-			} else {
-				tegra_hdmi_setup_audio_infoframe(hdmi);
-				tegra_hdmi_enable_audio_infoframe(hdmi);
-				tegra_hdmi_enable_audio(hdmi);
-			}
+			tegra_hdmi_reconfigure_audio(hdmi);
 		} else {
 			tegra_hdmi_disable_audio_infoframe(hdmi);
 			tegra_hdmi_disable_audio(hdmi);
@@ -1660,6 +1789,8 @@ static int tegra_hdmi_probe(struct platform_device *pdev)
 	hdmi->stereo = false;
 	hdmi->dvi = false;
 
+	mutex_init(&hdmi->audio_lock);
+
 	hdmi->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(hdmi->clk)) {
 		dev_err(&pdev->dev, "failed to get clock\n");