ENGR00172342-2 EDID parse audio data blocks

Add functionality to parse Audio Data Blocks from EDID data to
find out what modes of LPCM are suppored by the HDMI sink device.

The parsed settings are saved in the hdmi mfd.  The HDMI audio driver
will check the settings when the audio stream is opened and will
then apply appropriate constraints.

If we are unable to read from the EDID, then we default to supporting
Basic Audio as defined by the HDMI specification (stereo, 16 bit,
32KHz, 44.1KHz, 48KHz PCM).

Signed-off-by: Alan Tull <r80115@freescale.com>

7 files changed, 213 insertions, 44 deletions

diff --git a/drivers/mfd/mxc-hdmi-core.c b/drivers/mfd/mxc-hdmi-core.c
index 5f86788750a1..1aa92a01c40c 100644
--- a/drivers/mfd/mxc-hdmi-core.c
+++ b/drivers/mfd/mxc-hdmi-core.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2011 Freescale Semiconductor, Inc.
+ * Copyright (C) 2011-2012 Freescale Semiconductor, Inc.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -36,6 +36,7 @@
 #include <mach/clock.h>
 #include <mach/mxc_hdmi.h>
 #include <mach/ipu-v3.h>
+#include <mach/mxc_edid.h>
 #include "../mxc/ipu3/ipu_prv.h"
 #include <linux/mfd/mxc-hdmi-core.h>
 #include <linux/fsl_devices.h>
@@ -48,18 +49,20 @@ struct mxc_hdmi_data {
 };
 
 static unsigned long hdmi_base;
-struct clk *isfr_clk;
-struct clk *iahb_clk;
+static struct clk *isfr_clk;
+static struct clk *iahb_clk;
 static unsigned int irq_enable_cnt;
-spinlock_t irq_spinlock;
-bool irq_initialized;
-bool irq_enabled;
-unsigned int sample_rate;
-unsigned long pixel_clk_rate;
-struct clk *pixel_clk;
-int hdmi_ratio;
+static spinlock_t irq_spinlock;
+static spinlock_t edid_spinlock;
+static bool irq_initialized;
+static bool irq_enabled;
+static unsigned int sample_rate;
+static unsigned long pixel_clk_rate;
+static struct clk *pixel_clk;
+static int hdmi_ratio;
 int mxc_hdmi_ipu_id;
 int mxc_hdmi_disp_id;
+static struct mxc_edid_cfg hdmi_core_edid_cfg;
 
 u8 hdmi_readb(unsigned int reg)
 {
@@ -466,6 +469,24 @@ void hdmi_set_sample_rate(unsigned int rate)
 	hdmi_set_clk_regenerator();
 }
 
+void hdmi_set_edid_cfg(struct mxc_edid_cfg *cfg)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&edid_spinlock, flags);
+	memcpy(&hdmi_core_edid_cfg, cfg, sizeof(struct mxc_edid_cfg));
+	spin_unlock_irqrestore(&edid_spinlock, flags);
+}
+
+void hdmi_get_edid_cfg(struct mxc_edid_cfg *cfg)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&edid_spinlock, flags);
+	memcpy(cfg, &hdmi_core_edid_cfg, sizeof(struct mxc_edid_cfg));
+	spin_unlock_irqrestore(&edid_spinlock, flags);
+}
+
 static int mxc_hdmi_core_probe(struct platform_device *pdev)
 {
 	struct fsl_mxc_hdmi_core_platform_data *pdata = pdev->dev.platform_data;
@@ -497,6 +518,7 @@ static int mxc_hdmi_core_probe(struct platform_device *pdev)
 	irq_initialized = false;
 	irq_enabled = true;
 	spin_lock_init(&irq_spinlock);
+	spin_lock_init(&edid_spinlock);
 
 	isfr_clk = clk_get(&hdmi_data->pdev->dev, "hdmi_isfr_clk");
 	if (IS_ERR(isfr_clk)) {
diff --git a/drivers/video/mxc/mxc_edid.c b/drivers/video/mxc/mxc_edid.c
index 2fa655d345c5..e8a2b9761b65 100644
--- a/drivers/video/mxc/mxc_edid.c
+++ b/drivers/video/mxc/mxc_edid.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2009-2011 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2009-2012 Freescale Semiconductor, Inc. All Rights Reserved.
  */
 
 /*
@@ -313,6 +313,42 @@ int mxc_edid_parse_ext_blk(unsigned char *edid,
 					break;
 				}
 			case 0x1: /*Audio data block*/
+				{
+					u8 audio_format, max_ch, byte1, byte2, byte3;
+
+					i = 0;
+					cfg->max_channels = 0;
+					cfg->sample_rates = 0;
+					cfg->sample_sizes = 0;
+
+					while (i < blklen) {
+						byte1 = edid[index + 1];
+						byte2 = edid[index + 2];
+						byte3 = edid[index + 3];
+						index += 3;
+						i += 3;
+
+						audio_format = byte1 >> 3;
+						max_ch = (byte1 & 0x07) + 1;
+
+						DPRINTK("Audio Format Descriptor : %2d\n", audio_format);
+						DPRINTK("Max Number of Channels  : %2d\n", max_ch);
+						DPRINTK("Sample Rates            : %02x\n", byte2);
+
+						/* ALSA can't specify specific compressed
+						 * formats, so only care about PCM for now. */
+						if (audio_format == AUDIO_CODING_TYPE_LPCM) {
+							if (max_ch > cfg->max_channels)
+								cfg->max_channels = max_ch;
+
+							cfg->sample_rates |= byte2;
+							cfg->sample_sizes |= byte3 & 0x7;
+							DPRINTK("Sample Sizes            : %02x\n",
+								byte3 & 0x7);
+						}
+					}
+					break;
+				}
 			case 0x4: /*Speaker allocation block*/
 			case 0x7: /*User extended block*/
 			default:
diff --git a/drivers/video/mxc_hdmi.c b/drivers/video/mxc_hdmi.c
index 35df3d94deb6..0462f09a8fee 100644
--- a/drivers/video/mxc_hdmi.c
+++ b/drivers/video/mxc_hdmi.c
@@ -1364,6 +1364,9 @@ static int mxc_hdmi_read_edid(struct mxc_hdmi *hdmi)
 	if (ret < 0)
 		return HDMI_EDID_FAIL;
 
+	/* Save edid cfg for audio driver */
+	hdmi_set_edid_cfg(&hdmi->edid_cfg);
+
 	if (!memcmp(edid_old, hdmi->edid, HDMI_EDID_LEN)) {
 		dev_info(&hdmi->pdev->dev, "same edid\n");
 		return HDMI_EDID_SAME;
diff --git a/include/linux/mfd/mxc-hdmi-core.h b/include/linux/mfd/mxc-hdmi-core.h
index 8c6ce456ddad..b607feec147a 100644
--- a/include/linux/mfd/mxc-hdmi-core.h
+++ b/include/linux/mfd/mxc-hdmi-core.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright (C) 2011-2012 Freescale Semiconductor, Inc. All Rights Reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -19,6 +19,8 @@
 #ifndef __LINUX_MXC_HDMI_CORE_H_
 #define __LINUX_MXC_HDMI_CORE_H_
 
+#include <mach/mxc_edid.h>
+
 #define IRQ_DISABLE_SUCCEED	0
 #define IRQ_DISABLE_FAIL	1
 
@@ -38,6 +40,9 @@ void hdmi_set_sample_rate(unsigned int rate);
 void hdmi_init_clk_regenerator(void);
 void hdmi_clk_regenerator_update_pixel_clock(void);
 
+void hdmi_set_edid_cfg(struct mxc_edid_cfg *cfg);
+void hdmi_get_edid_cfg(struct mxc_edid_cfg *cfg);
+
 extern int mxc_hdmi_ipu_id;
 extern int mxc_hdmi_disp_id;
 
diff --git a/sound/soc/codecs/mxc_hdmi.c b/sound/soc/codecs/mxc_hdmi.c
index c6a6bcbdbfd9..70c9b8c9bfe0 100644
--- a/sound/soc/codecs/mxc_hdmi.c
+++ b/sound/soc/codecs/mxc_hdmi.c
@@ -1,7 +1,7 @@
 /*
  * MXC HDMI ALSA Soc Codec Driver
  *
- * Copyright (C) 2011 Freescale Semiconductor, Inc.
+ * Copyright (C) 2011-2012 Freescale Semiconductor, Inc.
  */
 
 /*
@@ -42,6 +42,7 @@
 #include <mach/hardware.h>
 
 #include <linux/mfd/mxc-hdmi-core.h>
+#include <mach/mxc_edid.h>
 #include <mach/mxc_hdmi.h>
 #include "../imx/imx-hdmi.h"
 
@@ -53,6 +54,16 @@ struct mxc_hdmi_priv {
 	struct clk *iahb_clk;
 };
 
+static struct mxc_edid_cfg edid_cfg;
+
+static unsigned int playback_rates[HDMI_MAX_RATES];
+static unsigned int playback_sample_size[HDMI_MAX_SAMPLE_SIZE];
+static unsigned int playback_channels[HDMI_MAX_CHANNEL_CONSTRAINTS];
+
+static struct snd_pcm_hw_constraint_list playback_constraint_rates;
+static struct snd_pcm_hw_constraint_list playback_constraint_bits;
+static struct snd_pcm_hw_constraint_list playback_constraint_channels;
+
 #ifdef DEBUG
 static void dumpregs(void)
 {
@@ -100,19 +111,126 @@ static void hdmi_set_audio_infoframe(void)
 	hdmi_writeb(0x00, HDMI_FC_AUDICONF2);
 }
 
-static unsigned int hdmi_playback_rates[] = { 32000, 44100, 48000, 88200, 96000 };
-
-static struct snd_pcm_hw_constraint_list playback_rate_constraints = {
-	.count = ARRAY_SIZE(hdmi_playback_rates),
-	.list = hdmi_playback_rates,
-	.mask = 0,
+static int cea_audio_rates[HDMI_MAX_RATES] = {
+	32000,
+	44100,
+	48000,
+	88200,
+	96000,
+	176400,
+	192000,
 };
 
+static void mxc_hdmi_get_playback_rates(void)
+{
+	int i, count = 0;
+	u8 rates;
+
+	/* always assume basic audio support */
+	rates = edid_cfg.sample_rates | 0x7;
+
+	for (i = 0 ; i < HDMI_MAX_RATES ; i++)
+		if ((rates & (1 << i)) != 0)
+			playback_rates[count++] = cea_audio_rates[i];
+
+	playback_constraint_rates.list = playback_rates;
+	playback_constraint_rates.count = count;
+
+#ifdef DEBUG
+	for (i = 0 ; i < playback_constraint_rates.count ; i++)
+		pr_debug("%s: constraint = %d Hz\n", __func__,
+			 playback_rates[i]);
+#endif
+}
+
+static void mxc_hdmi_get_playback_sample_size(void)
+{
+	int i = 0;
+
+	/* always assume basic audio support */
+	playback_sample_size[i++] = 16;
+
+	if (edid_cfg.sample_sizes & 0x2)
+		playback_sample_size[i++] = 20;
+
+	if (edid_cfg.sample_sizes & 0x4)
+		playback_sample_size[i++] = 24;
+
+	playback_constraint_bits.list = playback_sample_size;
+	playback_constraint_bits.count = i;
+
+#ifdef DEBUG
+	for (i = 0 ; i < playback_constraint_bits.count ; i++)
+		pr_debug("%s: constraint = %d bits\n", __func__,
+			 playback_sample_size[i]);
+#endif
+}
+
+static void mxc_hdmi_get_playback_channels(void)
+{
+	int channels = 2, i = 0;
+
+	/* always assume basic audio support */
+	playback_channels[i++] = channels;
+	channels += 2;
+
+	while ((i < HDMI_MAX_CHANNEL_CONSTRAINTS) &&
+		(channels <= edid_cfg.max_channels)) {
+		playback_channels[i++] = channels;
+		channels += 2;
+	}
+
+	playback_constraint_channels.list = playback_channels;
+	playback_constraint_channels.count = i;
+
+#ifdef DEBUG
+	for (i = 0 ; i < playback_constraint_channels.count ; i++)
+		pr_debug("%s: constraint = %d channels\n", __func__,
+			 playback_channels[i]);
+#endif
+}
+
+static int mxc_hdmi_update_constraints(struct mxc_hdmi_priv *priv,
+				       struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	int ret;
+
+	hdmi_get_edid_cfg(&edid_cfg);
+
+	mxc_hdmi_get_playback_rates();
+	ret = snd_pcm_hw_constraint_list(substream->runtime, 0,
+					SNDRV_PCM_HW_PARAM_RATE,
+					&playback_constraint_rates);
+	if (ret < 0)
+		return ret;
+
+	mxc_hdmi_get_playback_sample_size();
+	ret = snd_pcm_hw_constraint_list(substream->runtime, 0,
+					SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
+					&playback_constraint_bits);
+	if (ret < 0)
+		return ret;
+
+	mxc_hdmi_get_playback_channels();
+	ret = snd_pcm_hw_constraint_list(runtime, 0,
+					SNDRV_PCM_HW_PARAM_CHANNELS,
+					&playback_constraint_channels);
+	if (ret < 0)
+		return ret;
+
+	ret = snd_pcm_hw_constraint_integer(substream->runtime,
+			SNDRV_PCM_HW_PARAM_PERIODS);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
 static int mxc_hdmi_codec_startup(struct snd_pcm_substream *substream,
 				  struct snd_soc_dai *dai)
 {
 	struct mxc_hdmi_priv *hdmi_priv = snd_soc_dai_get_drvdata(dai);
-	struct snd_pcm_runtime *runtime = substream->runtime;
 	int ret;
 
 	clk_enable(hdmi_priv->isfr_clk);
@@ -122,14 +240,7 @@ static int mxc_hdmi_codec_startup(struct snd_pcm_substream *substream,
 		(int)clk_get_rate(hdmi_priv->isfr_clk),
 		(int)clk_get_rate(hdmi_priv->iahb_clk));
 
-	ret = snd_pcm_hw_constraint_list(runtime, 0,
-					 SNDRV_PCM_HW_PARAM_RATE,
-					 &playback_rate_constraints);
-	if (ret < 0)
-		return ret;
-
-	ret = snd_pcm_hw_constraint_integer(runtime,
-					SNDRV_PCM_HW_PARAM_PERIODS);
+	ret = mxc_hdmi_update_constraints(hdmi_priv, substream);
 	if (ret < 0)
 		return ret;
 
diff --git a/sound/soc/imx/imx-hdmi-dma.c b/sound/soc/imx/imx-hdmi-dma.c
index 9ce99efccc1b..d0c4d52e9c56 100644
--- a/sound/soc/imx/imx-hdmi-dma.c
+++ b/sound/soc/imx/imx-hdmi-dma.c
@@ -649,14 +649,6 @@ static struct snd_pcm_hardware snd_imx_hardware = {
 	.fifo_size = 0,
 };
 
-static unsigned int hw_channels[] = {2, 4, 6, 8};
-
-static struct snd_pcm_hw_constraint_list hw_constraint_channels = {
-	.count = ARRAY_SIZE(hw_channels),
-	.list = hw_channels,
-	.mask = 0,
-};
-
 static void hdmi_dma_irq_enable(struct imx_hdmi_dma_runtime_data *rtd)
 {
 	unsigned long flags;
@@ -712,12 +704,6 @@ static int hdmi_dma_open(struct snd_pcm_substream *substream)
 	if (ret < 0)
 		return ret;
 
-	ret = snd_pcm_hw_constraint_list(runtime, 0,
-					SNDRV_PCM_HW_PARAM_CHANNELS,
-					&hw_constraint_channels);
-	if (ret < 0)
-		return ret;
-
 	snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
 
 	hdmi_dma_irq_enable(hdmi_dma_priv);
diff --git a/sound/soc/imx/imx-hdmi.h b/sound/soc/imx/imx-hdmi.h
index 52c58dd516d5..11737579af31 100644
--- a/sound/soc/imx/imx-hdmi.h
+++ b/sound/soc/imx/imx-hdmi.h
@@ -1,7 +1,7 @@
 /*
  * MXC HDMI ALSA Soc Codec Driver
  *
- * Copyright (C) 2011 Freescale Semiconductor, Inc.
+ * Copyright (C) 2011-2012 Freescale Semiconductor, Inc.
  */
 
 /*
@@ -31,11 +31,17 @@ struct imx_hdmi {
 	struct platform_device *soc_platform_pdev;
 };
 
+#define HDMI_MAX_RATES 7
+#define HDMI_MAX_SAMPLE_SIZE 3
+#define HDMI_MAX_CHANNEL_CONSTRAINTS 4
+
 #define MXC_HDMI_RATES_PLAYBACK			(SNDRV_PCM_RATE_32000 | \
 						 SNDRV_PCM_RATE_44100 | \
 						 SNDRV_PCM_RATE_48000 | \
 						 SNDRV_PCM_RATE_88200 | \
-						 SNDRV_PCM_RATE_96000)
+						 SNDRV_PCM_RATE_96000 | \
+						 SNDRV_PCM_RATE_176400 | \
+						 SNDRV_PCM_RATE_192000)
 
 #define MXC_HDMI_FORMATS_PLAYBACK		(SNDRV_PCM_FMTBIT_S16_LE | \
 						 SNDRV_PCM_FMTBIT_S24_LE)