ASoC: hdmi-codec: Add hdmi-codec for external HDMI-encoders

The hdmi-codec is a platform device driver to be registered from
drivers of external HDMI encoders with I2S and/or spdif interface. The
driver in turn registers an ASoC codec for the HDMI encoder's audio
functionality.

The structures and definitions in the API header are mostly redundant
copies of similar structures in ASoC headers. This is on purpose to
avoid direct dependencies to ASoC structures in video side driver.
Signed-off-by: Jyri Sarha <jsarha@ti.com>
Acked-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Acked-by: PC Liao <pc.liao@mediatek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

include/sound/hdmi-codec.h

+/*
+ * hdmi-codec.h - HDMI Codec driver API
+ *
+ * Copyright (C) 2014 Texas Instruments Incorporated - http://www.ti.com
+ *
+ * Author: Jyri Sarha <jsarha@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+#ifndef __HDMI_CODEC_H__
+#define __HDMI_CODEC_H__
+
+#include <linux/hdmi.h>
+#include <drm/drm_edid.h>
+#include <sound/asoundef.h>
+#include <uapi/sound/asound.h>
+
+/*
+ * Protocol between ASoC cpu-dai and HDMI-encoder
+ */
+struct hdmi_codec_daifmt {
+	enum {
+		HDMI_I2S,
+		HDMI_RIGHT_J,
+		HDMI_LEFT_J,
+		HDMI_DSP_A,
+		HDMI_DSP_B,
+		HDMI_AC97,
+		HDMI_SPDIF,
+	} fmt;
+	int bit_clk_inv:1;
+	int frame_clk_inv:1;
+	int bit_clk_master:1;
+	int frame_clk_master:1;
+};
+
+/*
+ * HDMI audio parameters
+ */
+struct hdmi_codec_params {
+	struct hdmi_audio_infoframe cea;
+	struct snd_aes_iec958 iec;
+	int sample_rate;
+	int sample_width;
+	int channels;
+};
+
+struct hdmi_codec_ops {
+	/*
+	 * Called when ASoC starts an audio stream setup.
+	 * Optional
+	 */
+	int (*audio_startup)(struct device *dev);
+
+	/*
+	 * Configures HDMI-encoder for audio stream.
+	 * Mandatory
+	 */
+	int (*hw_params)(struct device *dev,
+			 struct hdmi_codec_daifmt *fmt,
+			 struct hdmi_codec_params *hparms);
+
+	/*
+	 * Shuts down the audio stream.
+	 * Mandatory
+	 */
+	void (*audio_shutdown)(struct device *dev);
+
+	/*
+	 * Mute/unmute HDMI audio stream.
+	 * Optional
+	 */
+	int (*digital_mute)(struct device *dev, bool enable);
+
+	/*
+	 * Provides EDID-Like-Data from connected HDMI device.
+	 * Optional
+	 */
+	int (*get_eld)(struct device *dev, uint8_t *buf, size_t len);
+};
+
+/* HDMI codec initalization data */
+struct hdmi_codec_pdata {
+	const struct hdmi_codec_ops *ops;
+	uint i2s:1;
+	uint spdif:1;
+	int max_i2s_channels;
+};
+
+#define HDMI_CODEC_DRV_NAME "hdmi-audio-codec"
+
+#endif /* __HDMI_CODEC_H__ */

sound/soc/codecs/Kconfig

@@ -88,6 +88,7 @@ config SND_SOC_ALL_CODECS
 	select SND_SOC_MC13783 if MFD_MC13XXX
 	select SND_SOC_ML26124 if I2C
 	select SND_SOC_NAU8825 if I2C
+	select SND_SOC_HDMI_CODEC
 	select SND_SOC_PCM1681 if I2C
 	select SND_SOC_PCM179X_I2C if I2C
 	select SND_SOC_PCM179X_SPI if SPI_MASTER
@@ -477,6 +478,11 @@ config SND_SOC_BT_SCO
 config SND_SOC_DMIC
 	tristate
 
+config SND_SOC_HDMI_CODEC
+       tristate
+       select SND_PCM_ELD
+       select SND_PCM_IEC958
+
 config SND_SOC_ES8328
 	tristate "Everest Semi ES8328 CODEC"
 

sound/soc/codecs/Makefile

@@ -81,6 +81,7 @@ snd-soc-max9850-objs := max9850.o
 snd-soc-mc13783-objs := mc13783.o
 snd-soc-ml26124-objs := ml26124.o
 snd-soc-nau8825-objs := nau8825.o
+snd-soc-hdmi-codec-objs := hdmi-codec.o
 snd-soc-pcm1681-objs := pcm1681.o
 snd-soc-pcm179x-codec-objs := pcm179x.o
 snd-soc-pcm179x-i2c-objs := pcm179x-i2c.o
@@ -290,6 +291,7 @@ obj-$(CONFIG_SND_SOC_MAX9850)	+= snd-soc-max9850.o
 obj-$(CONFIG_SND_SOC_MC13783)	+= snd-soc-mc13783.o
 obj-$(CONFIG_SND_SOC_ML26124)	+= snd-soc-ml26124.o
 obj-$(CONFIG_SND_SOC_NAU8825)   += snd-soc-nau8825.o
+obj-$(CONFIG_SND_SOC_HDMI_CODEC)	+= snd-soc-hdmi-codec.o
 obj-$(CONFIG_SND_SOC_PCM1681)	+= snd-soc-pcm1681.o
 obj-$(CONFIG_SND_SOC_PCM179X)	+= snd-soc-pcm179x-codec.o
 obj-$(CONFIG_SND_SOC_PCM179X_I2C)	+= snd-soc-pcm179x-i2c.o