[PATCH v1 5/5] drm: bridge: dw_hdmi: Audio: Add General Parallel Audio (GPA) driver

[Sandor.yu@nxp.com]

From: Sandor Yu <Sandor.yu@nxp.com>

General Parallel Audio (GPA) interface is one of the supported
audio interface for synopsys HDMI module, which has verified for
i.MX8MP platform.
This is initial version for GPA.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Signed-off-by: Sandor Yu <Sandor.yu@nxp.com>
---
 drivers/gpu/drm/bridge/synopsys/Kconfig       |  11 +
 drivers/gpu/drm/bridge/synopsys/Makefile      |   1 +
 .../drm/bridge/synopsys/dw-hdmi-gp-audio.c    | 199 ++++++++++++++++++
 drivers/gpu/drm/bridge/synopsys/dw-hdmi.c     | 128 ++++++++++-
 drivers/gpu/drm/bridge/synopsys/dw-hdmi.h     |  13 +-
 include/drm/bridge/dw_hdmi.h                  |   5 +
 6 files changed, 354 insertions(+), 3 deletions(-)
 create mode 100644 drivers/gpu/drm/bridge/synopsys/dw-hdmi-gp-audio.c

diff --git a/drivers/gpu/drm/bridge/synopsys/Kconfig b/drivers/gpu/drm/bridge/synopsys/Kconfig
index 21a1be3ced0f..e398b58c996d 100644
--- a/drivers/gpu/drm/bridge/synopsys/Kconfig
+++ b/drivers/gpu/drm/bridge/synopsys/Kconfig
@@ -25,6 +25,17 @@ config DRM_DW_HDMI_I2S_AUDIO
 	  Support the I2S Audio interface which is part of the Synopsys
 	  Designware HDMI block.
 
+config DRM_DW_HDMI_GP_AUDIO
+	tristate "Synopsys Designware GP Audio interface"
+	depends on DRM_DW_HDMI && SND
+	select SND_PCM
+	select SND_PCM_ELD
+	select SND_PCM_IEC958
+	help
+	  Support the GP Audio interface which is part of the Synopsys
+	  Designware HDMI block.  This is used in conjunction with
+	  the i.MX865 HDMI driver.
+
 config DRM_DW_HDMI_CEC
 	tristate "Synopsis Designware CEC interface"
 	depends on DRM_DW_HDMI
diff --git a/drivers/gpu/drm/bridge/synopsys/Makefile b/drivers/gpu/drm/bridge/synopsys/Makefile
index 91d746ad5de1..ce715562e9e5 100644
--- a/drivers/gpu/drm/bridge/synopsys/Makefile
+++ b/drivers/gpu/drm/bridge/synopsys/Makefile
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_DRM_DW_HDMI) += dw-hdmi.o
 obj-$(CONFIG_DRM_DW_HDMI_AHB_AUDIO) += dw-hdmi-ahb-audio.o
+obj-$(CONFIG_DRM_DW_HDMI_GP_AUDIO) += dw-hdmi-gp-audio.o
 obj-$(CONFIG_DRM_DW_HDMI_I2S_AUDIO) += dw-hdmi-i2s-audio.o
 obj-$(CONFIG_DRM_DW_HDMI_CEC) += dw-hdmi-cec.o
 
diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-gp-audio.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-gp-audio.c
new file mode 100644
index 000000000000..10a957c85a83
--- /dev/null
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-gp-audio.c
@@ -0,0 +1,199 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * dw-hdmi-gp-audio.c
+ *
+ * Copyright 2020-2022 NXP
+ */
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <drm/bridge/dw_hdmi.h>
+#include <drm/drm_edid.h>
+#include <drm/drm_connector.h>
+
+#include <sound/hdmi-codec.h>
+#include <sound/asoundef.h>
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/pcm.h>
+#include <sound/pcm_drm_eld.h>
+#include <sound/pcm_iec958.h>
+#include <sound/dmaengine_pcm.h>
+
+#include "dw-hdmi-audio.h"
+
+#define DRIVER_NAME "dw-hdmi-gp-audio"
+#define DRV_NAME    "hdmi-gp-audio"
+
+struct snd_dw_hdmi {
+	struct dw_hdmi_audio_data data;
+	struct platform_device  *audio_pdev;
+	unsigned int pos;
+};
+
+struct dw_hdmi_channel_conf {
+	u8 conf1;
+	u8 ca;
+};
+
+/*
+ * The default mapping of ALSA channels to HDMI channels and speaker
+ * allocation bits.  Note that we can't do channel remapping here -
+ * channels must be in the same order.
+ *
+ * Mappings for alsa-lib pcm/surround*.conf files:
+ *
+ *		Front	Sur4.0	Sur4.1	Sur5.0	Sur5.1	Sur7.1
+ * Channels	2	4	6	6	6	8
+ *
+ * Our mapping from ALSA channel to CEA686D speaker name and HDMI channel:
+ *
+ *				Number of ALSA channels
+ * ALSA Channel	2	3	4	5	6	7	8
+ * 0		FL:0	=	=	=	=	=	=
+ * 1		FR:1	=	=	=	=	=	=
+ * 2			FC:3	RL:4	LFE:2	=	=	=
+ * 3				RR:5	RL:4	FC:3	=	=
+ * 4					RR:5	RL:4	=	=
+ * 5						RR:5	=	=
+ * 6							RC:6	=
+ * 7							RLC/FRC	RLC/FRC
+ */
+static struct dw_hdmi_channel_conf default_hdmi_channel_config[7] = {
+	{ 0x03, 0x00 },	/* FL,FR */
+	{ 0x0b, 0x02 },	/* FL,FR,FC */
+	{ 0x33, 0x08 },	/* FL,FR,RL,RR */
+	{ 0x37, 0x09 },	/* FL,FR,LFE,RL,RR */
+	{ 0x3f, 0x0b },	/* FL,FR,LFE,FC,RL,RR */
+	{ 0x7f, 0x0f },	/* FL,FR,LFE,FC,RL,RR,RC */
+	{ 0xff, 0x13 },	/* FL,FR,LFE,FC,RL,RR,[FR]RC,[FR]LC */
+};
+
+static int audio_hw_params(struct device *dev,  void *data,
+			   struct hdmi_codec_daifmt *daifmt,
+			   struct hdmi_codec_params *params)
+{
+	struct snd_dw_hdmi *dw = dev_get_drvdata(dev);
+	int ret = 0;
+	u8 ca;
+
+	dw_hdmi_set_sample_rate(dw->data.hdmi, params->sample_rate);
+
+	ca = default_hdmi_channel_config[params->channels - 2].ca;
+
+	dw_hdmi_set_channel_count(dw->data.hdmi, params->channels);
+	dw_hdmi_set_channel_allocation(dw->data.hdmi, ca);
+
+	dw_hdmi_set_sample_non_pcm(dw->data.hdmi,
+				   params->iec.status[0] & IEC958_AES0_NONAUDIO);
+	dw_hdmi_set_sample_width(dw->data.hdmi, params->sample_width);
+
+	return ret;
+}
+
+static void audio_shutdown(struct device *dev, void *data)
+{
+}
+
+static int audio_mute_stream(struct device *dev, void *data,
+			      bool enable, int direction)
+{
+	struct snd_dw_hdmi *dw = dev_get_drvdata(dev);
+	int ret = 0;
+
+	if (!enable)
+		dw_hdmi_audio_enable(dw->data.hdmi);
+	else
+		dw_hdmi_audio_disable(dw->data.hdmi);
+
+	return ret;
+}
+
+static int audio_get_eld(struct device *dev, void *data,
+			 u8 *buf, size_t len)
+{
+	struct dw_hdmi_audio_data *audio = data;
+	u8 *eld;
+
+	eld = audio->get_eld(audio->hdmi);
+	if (eld)
+		memcpy(buf, eld, min_t(size_t, MAX_ELD_BYTES, len));
+	else
+		/* Pass en empty ELD if connector not available */
+		memset(buf, 0, len);
+
+	return 0;
+}
+
+static int audio_hook_plugged_cb(struct device *dev, void *data,
+				 hdmi_codec_plugged_cb fn,
+				 struct device *codec_dev)
+{
+	struct snd_dw_hdmi *dw = dev_get_drvdata(dev);
+
+	return dw_hdmi_set_plugged_cb(dw->data.hdmi, fn, codec_dev);
+}
+
+static const struct hdmi_codec_ops audio_codec_ops = {
+	.hw_params = audio_hw_params,
+	.audio_shutdown = audio_shutdown,
+	.mute_stream = audio_mute_stream,
+	.get_eld = audio_get_eld,
+	.hook_plugged_cb = audio_hook_plugged_cb,
+};
+
+static int snd_dw_hdmi_probe(struct platform_device *pdev)
+{
+	struct dw_hdmi_audio_data *data = pdev->dev.platform_data;
+	struct snd_dw_hdmi *dw;
+
+	const struct hdmi_codec_pdata codec_data = {
+		.i2s = 1,
+		.spdif = 0,
+		.ops = &audio_codec_ops,
+		.max_i2s_channels = 8,
+		.data = data,
+	};
+
+	dw = devm_kzalloc(&pdev->dev, sizeof(*dw), GFP_KERNEL);
+	if (!dw)
+		return -ENOMEM;
+
+	dw->data = *data;
+
+	platform_set_drvdata(pdev, dw);
+
+	dw->audio_pdev = platform_device_register_data(&pdev->dev,
+						       HDMI_CODEC_DRV_NAME, 1,
+						       &codec_data,
+						       sizeof(codec_data));
+
+	return PTR_ERR_OR_ZERO(dw->audio_pdev);
+}
+
+static int snd_dw_hdmi_remove(struct platform_device *pdev)
+{
+	struct snd_dw_hdmi *dw = platform_get_drvdata(pdev);
+
+	platform_device_unregister(dw->audio_pdev);
+
+	return 0;
+}
+
+static struct platform_driver snd_dw_hdmi_driver = {
+	.probe	= snd_dw_hdmi_probe,
+	.remove	= snd_dw_hdmi_remove,
+	.driver	= {
+		.name = DRIVER_NAME,
+	},
+};
+
+module_platform_driver(snd_dw_hdmi_driver);
+
+MODULE_AUTHOR("Shengjiu Wang <shengjiu.wang@nxp.com>");
+MODULE_DESCRIPTION("Synopsis Designware HDMI GPA ALSA interface");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRIVER_NAME);
diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
index c6e701acd416..1385d8f7870e 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
@@ -191,7 +191,10 @@ struct dw_hdmi {
 
 	spinlock_t audio_lock;
 	struct mutex audio_mutex;
+	unsigned int sample_non_pcm;
+	unsigned int sample_width;
 	unsigned int sample_rate;
+	unsigned int channels;
 	unsigned int audio_cts;
 	unsigned int audio_n;
 	bool audio_enable;
@@ -589,6 +592,8 @@ static unsigned int hdmi_compute_n(unsigned int freq, unsigned long pixel_clk)
 			n = 4096;
 		else if (pixel_clk == 74176000 || pixel_clk == 148352000)
 			n = 11648;
+		else if (pixel_clk == 297000000)
+			n = 3072;
 		else
 			n = 4096;
 		n *= mult;
@@ -601,6 +606,8 @@ static unsigned int hdmi_compute_n(unsigned int freq, unsigned long pixel_clk)
 			n = 17836;
 		else if (pixel_clk == 148352000)
 			n = 8918;
+		else if (pixel_clk == 297000000)
+			n = 4704;
 		else
 			n = 6272;
 		n *= mult;
@@ -615,6 +622,8 @@ static unsigned int hdmi_compute_n(unsigned int freq, unsigned long pixel_clk)
 			n = 11648;
 		else if (pixel_clk == 148352000)
 			n = 5824;
+		else if (pixel_clk == 297000000)
+			n = 5120;
 		else
 			n = 6144;
 		n *= mult;
@@ -660,7 +669,7 @@ static void hdmi_set_clk_regenerator(struct dw_hdmi *hdmi,
 	config3 = hdmi_readb(hdmi, HDMI_CONFIG3_ID);
 
 	/* Only compute CTS when using internal AHB audio */
-	if (config3 & HDMI_CONFIG3_AHBAUDDMA) {
+	if ((config3 & HDMI_CONFIG3_AHBAUDDMA) || (config3 & HDMI_CONFIG3_GPAUD)) {
 		/*
 		 * Compute the CTS value from the N value.  Note that CTS and N
 		 * can be up to 20 bits in total, so we need 64-bit math.  Also
@@ -702,6 +711,22 @@ static void hdmi_clk_regenerator_update_pixel_clock(struct dw_hdmi *hdmi)
 	mutex_unlock(&hdmi->audio_mutex);
 }
 
+void dw_hdmi_set_sample_width(struct dw_hdmi *hdmi, unsigned int width)
+{
+	mutex_lock(&hdmi->audio_mutex);
+	hdmi->sample_width = width;
+	mutex_unlock(&hdmi->audio_mutex);
+}
+EXPORT_SYMBOL_GPL(dw_hdmi_set_sample_width);
+
+void dw_hdmi_set_sample_non_pcm(struct dw_hdmi *hdmi, unsigned int non_pcm)
+{
+	mutex_lock(&hdmi->audio_mutex);
+	hdmi->sample_non_pcm = non_pcm;
+	mutex_unlock(&hdmi->audio_mutex);
+}
+EXPORT_SYMBOL_GPL(dw_hdmi_set_sample_non_pcm);
+
 void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate)
 {
 	mutex_lock(&hdmi->audio_mutex);
@@ -717,6 +742,7 @@ void dw_hdmi_set_channel_count(struct dw_hdmi *hdmi, unsigned int cnt)
 	u8 layout;
 
 	mutex_lock(&hdmi->audio_mutex);
+	hdmi->channels = cnt;
 
 	/*
 	 * For >2 channel PCM audio, we need to select layout 1
@@ -765,6 +791,87 @@ static u8 *hdmi_audio_get_eld(struct dw_hdmi *hdmi)
 	return hdmi->curr_conn->eld;
 }
 
+static void dw_hdmi_gp_audio_enable(struct dw_hdmi *hdmi)
+{
+	int sample_freq = 0x2, org_sample_freq = 0xD;
+	int ch_mask = BIT(hdmi->channels) - 1;
+
+	switch (hdmi->sample_rate) {
+	case 32000:
+		sample_freq = 0x03;
+		org_sample_freq = 0x0C;
+		break;
+	case 44100:
+		sample_freq = 0x00;
+		org_sample_freq = 0x0F;
+		break;
+	case 48000:
+		sample_freq = 0x02;
+		org_sample_freq = 0x0D;
+		break;
+	case 88200:
+		sample_freq = 0x08;
+		org_sample_freq = 0x07;
+		break;
+	case 96000:
+		sample_freq = 0x0A;
+		org_sample_freq = 0x05;
+		break;
+	case 176400:
+		sample_freq = 0x0C;
+		org_sample_freq = 0x03;
+		break;
+	case 192000:
+		sample_freq = 0x0E;
+		org_sample_freq = 0x01;
+		break;
+	default:
+		break;
+	}
+
+	hdmi_set_cts_n(hdmi, hdmi->audio_cts, hdmi->audio_n);
+	hdmi_enable_audio_clk(hdmi, true);
+
+	hdmi_writeb(hdmi, 0x1, HDMI_FC_AUDSCHNLS0);
+	hdmi_writeb(hdmi, hdmi->channels, HDMI_FC_AUDSCHNLS2);
+	hdmi_writeb(hdmi, 0x22, HDMI_FC_AUDSCHNLS3);
+	hdmi_writeb(hdmi, 0x22, HDMI_FC_AUDSCHNLS4);
+	hdmi_writeb(hdmi, 0x11, HDMI_FC_AUDSCHNLS5);
+	hdmi_writeb(hdmi, 0x11, HDMI_FC_AUDSCHNLS6);
+	hdmi_writeb(hdmi, (0x3 << 4) | sample_freq, HDMI_FC_AUDSCHNLS7);
+	hdmi_writeb(hdmi, (org_sample_freq << 4) | 0xb, HDMI_FC_AUDSCHNLS8);
+
+	hdmi_writeb(hdmi, ch_mask, HDMI_GP_CONF1);
+	hdmi_writeb(hdmi, 0x02, HDMI_GP_CONF2);
+	hdmi_writeb(hdmi, 0x01, HDMI_GP_CONF0);
+
+	hdmi_modb(hdmi,  0x3, 0x3, HDMI_FC_DATAUTO3);
+
+	/* hbr */
+	if (hdmi->sample_rate == 192000 && hdmi->channels == 8 &&
+	    hdmi->sample_width == 32 && hdmi->sample_non_pcm) {
+		hdmi_modb(hdmi, 0x01, 0x01, HDMI_GP_CONF2);
+	}
+
+	if (hdmi->phy.ops->enable_audio)
+		hdmi->phy.ops->enable_audio(hdmi, hdmi->phy.data,
+					    hdmi->channels,
+					    hdmi->sample_width,
+					    hdmi->sample_rate,
+					    hdmi->sample_non_pcm);
+}
+
+static void dw_hdmi_gp_audio_disable(struct dw_hdmi *hdmi)
+{
+	hdmi_set_cts_n(hdmi, hdmi->audio_cts, 0);
+
+	hdmi_modb(hdmi,  0, 0x3, HDMI_FC_DATAUTO3);
+	if (hdmi->phy.ops->disable_audio)
+		hdmi->phy.ops->disable_audio(hdmi, hdmi->phy.data);
+
+	hdmi_enable_audio_clk(hdmi, false);
+}
+
 static void dw_hdmi_ahb_audio_enable(struct dw_hdmi *hdmi)
 {
 	hdmi_set_cts_n(hdmi, hdmi->audio_cts, hdmi->audio_n);
@@ -3259,6 +3366,7 @@ struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
 	hdmi->plat_data = plat_data;
 	hdmi->dev = dev;
 	hdmi->sample_rate = 48000;
+	hdmi->channels = 2;
 	hdmi->disabled = true;
 	hdmi->rxsense = true;
 	hdmi->phy_mask = (u8)~(HDMI_PHY_HPD | HDMI_PHY_RX_SENSE);
@@ -3482,6 +3590,24 @@ struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
 		pdevinfo.size_data = sizeof(audio);
 		pdevinfo.dma_mask = DMA_BIT_MASK(32);
 		hdmi->audio = platform_device_register_full(&pdevinfo);
+	} else if (iores && config3 & HDMI_CONFIG3_GPAUD) {
+		struct dw_hdmi_audio_data audio;
+
+		audio.phys = iores->start;
+		audio.base = hdmi->regs;
+		audio.irq = irq;
+		audio.hdmi = hdmi;
+		audio.get_eld = hdmi_audio_get_eld;
+
+		hdmi->enable_audio = dw_hdmi_gp_audio_enable;
+		hdmi->disable_audio = dw_hdmi_gp_audio_disable;
+
+		pdevinfo.name = "dw-hdmi-gp-audio";
+		pdevinfo.id = PLATFORM_DEVID_NONE;
+		pdevinfo.data = &audio;
+		pdevinfo.size_data = sizeof(audio);
+		pdevinfo.dma_mask = DMA_BIT_MASK(32);
+		hdmi->audio = platform_device_register_full(&pdevinfo);
 	}
 
 	if (!plat_data->disable_cec && (config0 & HDMI_CONFIG0_CEC)) {
diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.h b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.h
index 1999db05bc3b..99aa1c03343b 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.h
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.h
@@ -158,8 +158,17 @@
 #define HDMI_FC_SPDDEVICEINF                    0x1062
 #define HDMI_FC_AUDSCONF                        0x1063
 #define HDMI_FC_AUDSSTAT                        0x1064
-#define HDMI_FC_AUDSCHNLS7                      0x106e
-#define HDMI_FC_AUDSCHNLS8                      0x106f
+#define HDMI_FC_AUDSV                           0x1065
+#define HDMI_FC_AUDSU                           0x1066
+#define HDMI_FC_AUDSCHNLS0                       0x1067
+#define HDMI_FC_AUDSCHNLS1                       0x1068
+#define HDMI_FC_AUDSCHNLS2                       0x1069
+#define HDMI_FC_AUDSCHNLS3                       0x106A
+#define HDMI_FC_AUDSCHNLS4                       0x106B
+#define HDMI_FC_AUDSCHNLS5                       0x106C
+#define HDMI_FC_AUDSCHNLS6                       0x106D
+#define HDMI_FC_AUDSCHNLS7                       0x106E
+#define HDMI_FC_AUDSCHNLS8                       0x106F
 #define HDMI_FC_DATACH0FILL                     0x1070
 #define HDMI_FC_DATACH1FILL                     0x1071
 #define HDMI_FC_DATACH2FILL                     0x1072
diff --git a/include/drm/bridge/dw_hdmi.h b/include/drm/bridge/dw_hdmi.h
index 70082f80a8c8..7f73c3398a54 100644
--- a/include/drm/bridge/dw_hdmi.h
+++ b/include/drm/bridge/dw_hdmi.h
@@ -121,6 +121,9 @@ struct dw_hdmi_phy_ops {
 	void (*update_hpd)(struct dw_hdmi *hdmi, void *data,
 			   bool force, bool disabled, bool rxsense);
 	void (*setup_hpd)(struct dw_hdmi *hdmi, void *data);
+	void (*enable_audio)(struct dw_hdmi *hdmi, void *data, int channel,
+			     int width, int rate, int non_pcm);
+	void (*disable_audio)(struct dw_hdmi *hdmi, void *data);
 };
 
 struct dw_hdmi_plat_data {
@@ -173,6 +176,8 @@ void dw_hdmi_setup_rx_sense(struct dw_hdmi *hdmi, bool hpd, bool rx_sense);
 
 int dw_hdmi_set_plugged_cb(struct dw_hdmi *hdmi, hdmi_codec_plugged_cb fn,
 			   struct device *codec_dev);
+void dw_hdmi_set_sample_non_pcm(struct dw_hdmi *hdmi, unsigned int non_pcm);
+void dw_hdmi_set_sample_width(struct dw_hdmi *hdmi, unsigned int width);
 void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate);
 void dw_hdmi_set_channel_count(struct dw_hdmi *hdmi, unsigned int cnt);
 void dw_hdmi_set_channel_status(struct dw_hdmi *hdmi, u8 *channel_status);
-- 
2.25.1