Re: [alsa-devel] [PATCH v5 6/6] drm/bridge: sii902x: Implement HDMI audio support

On 12/04/2019 11:52, Andrzej Hajda wrote:

On 22.03.2019 09:06, Jyri Sarha wrote:

...

Implement HDMI audio support by using ASoC HDMI codec. The commit implements the necessary callbacks and configuration for the HDMI codec and registers a virtual platform device for the codec to attach.

Signed-off-by: Jyri Sarha jsarha@ti.com

drivers/gpu/drm/bridge/sii902x.c | 459 ++++++++++++++++++++++++++++++- 1 file changed, 453 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c index 358cf81c5ea4..cb12e264111d 100644 --- a/drivers/gpu/drm/bridge/sii902x.c +++ b/drivers/gpu/drm/bridge/sii902x.c @@ -27,12 +27,15 @@ #include <linux/i2c.h> #include <linux/module.h> #include <linux/regmap.h> +#include <linux/clk.h>

#include <drm/drmP.h> #include <drm/drm_atomic_helper.h> #include <drm/drm_crtc_helper.h> #include <drm/drm_edid.h>

+#include <sound/hdmi-codec.h>

#define SII902X_TPI_VIDEO_DATA 0x0

#define SII902X_TPI_PIXEL_REPETITION 0x8 @@ -74,6 +77,77 @@ #define SII902X_AVI_POWER_STATE_MSK GENMASK(1, 0) #define SII902X_AVI_POWER_STATE_D(l) ((l) & SII902X_AVI_POWER_STATE_MSK)

+/* Audio */ +#define SII902X_TPI_I2S_ENABLE_MAPPING_REG 0x1f +#define SII902X_TPI_I2S_CONFIG_FIFO0 (0 << 0) +#define SII902X_TPI_I2S_CONFIG_FIFO1 (1 << 0) +#define SII902X_TPI_I2S_CONFIG_FIFO2 (2 << 0) +#define SII902X_TPI_I2S_CONFIG_FIFO3 (3 << 0) +#define SII902X_TPI_I2S_LEFT_RIGHT_SWAP (1 << 2) +#define SII902X_TPI_I2S_AUTO_DOWNSAMPLE (1 << 3) +#define SII902X_TPI_I2S_SELECT_SD0 (0 << 4) +#define SII902X_TPI_I2S_SELECT_SD1 (1 << 4) +#define SII902X_TPI_I2S_SELECT_SD2 (2 << 4) +#define SII902X_TPI_I2S_SELECT_SD3 (3 << 4) +#define SII902X_TPI_I2S_FIFO_ENABLE (1 << 7)

+#define SII902X_TPI_I2S_INPUT_CONFIG_REG 0x20 +#define SII902X_TPI_I2S_FIRST_BIT_SHIFT_YES (0 << 0) +#define SII902X_TPI_I2S_FIRST_BIT_SHIFT_NO (1 << 0) +#define SII902X_TPI_I2S_SD_DIRECTION_MSB_FIRST (0 << 1) +#define SII902X_TPI_I2S_SD_DIRECTION_LSB_FIRST (1 << 1) +#define SII902X_TPI_I2S_SD_JUSTIFY_LEFT (0 << 2) +#define SII902X_TPI_I2S_SD_JUSTIFY_RIGHT (1 << 2) +#define SII902X_TPI_I2S_WS_POLARITY_LOW (0 << 3) +#define SII902X_TPI_I2S_WS_POLARITY_HIGH (1 << 3) +#define SII902X_TPI_I2S_MCLK_MULTIPLIER_128 (0 << 4) +#define SII902X_TPI_I2S_MCLK_MULTIPLIER_256 (1 << 4) +#define SII902X_TPI_I2S_MCLK_MULTIPLIER_384 (2 << 4) +#define SII902X_TPI_I2S_MCLK_MULTIPLIER_512 (3 << 4) +#define SII902X_TPI_I2S_MCLK_MULTIPLIER_768 (4 << 4) +#define SII902X_TPI_I2S_MCLK_MULTIPLIER_1024 (5 << 4) +#define SII902X_TPI_I2S_MCLK_MULTIPLIER_1152 (6 << 4) +#define SII902X_TPI_I2S_MCLK_MULTIPLIER_192 (7 << 4) +#define SII902X_TPI_I2S_SCK_EDGE_FALLING (0 << 7) +#define SII902X_TPI_I2S_SCK_EDGE_RISING (1 << 7)

+#define SII902X_TPI_I2S_STRM_HDR_BASE 0x21 +#define SII902X_TPI_I2S_STRM_HDR_SIZE 5

+#define SII902X_TPI_AUDIO_CONFIG_BYTE2_REG 0x26 +#define SII902X_TPI_AUDIO_CODING_STREAM_HEADER (0 << 0) +#define SII902X_TPI_AUDIO_CODING_PCM (1 << 0) +#define SII902X_TPI_AUDIO_CODING_AC3 (2 << 0) +#define SII902X_TPI_AUDIO_CODING_MPEG1 (3 << 0) +#define SII902X_TPI_AUDIO_CODING_MP3 (4 << 0) +#define SII902X_TPI_AUDIO_CODING_MPEG2 (5 << 0) +#define SII902X_TPI_AUDIO_CODING_AAC (6 << 0) +#define SII902X_TPI_AUDIO_CODING_DTS (7 << 0) +#define SII902X_TPI_AUDIO_CODING_ATRAC (8 << 0) +#define SII902X_TPI_AUDIO_MUTE_DISABLE (0 << 4) +#define SII902X_TPI_AUDIO_MUTE_ENABLE (1 << 4) +#define SII902X_TPI_AUDIO_LAYOUT_2_CHANNELS (0 << 5) +#define SII902X_TPI_AUDIO_LAYOUT_8_CHANNELS (1 << 5) +#define SII902X_TPI_AUDIO_INTERFACE_DISABLE (0 << 6) +#define SII902X_TPI_AUDIO_INTERFACE_SPDIF (1 << 6) +#define SII902X_TPI_AUDIO_INTERFACE_I2S (2 << 6)

+#define SII902X_TPI_AUDIO_CONFIG_BYTE3_REG 0x27 +#define SII902X_TPI_AUDIO_FREQ_STREAM (0 << 3) +#define SII902X_TPI_AUDIO_FREQ_32KHZ (1 << 3) +#define SII902X_TPI_AUDIO_FREQ_44KHZ (2 << 3) +#define SII902X_TPI_AUDIO_FREQ_48KHZ (3 << 3) +#define SII902X_TPI_AUDIO_FREQ_88KHZ (4 << 3) +#define SII902X_TPI_AUDIO_FREQ_96KHZ (5 << 3) +#define SII902X_TPI_AUDIO_FREQ_176KHZ (6 << 3) +#define SII902X_TPI_AUDIO_FREQ_192KHZ (7 << 3) +#define SII902X_TPI_AUDIO_SAMPLE_SIZE_STREAM (0 << 6) +#define SII902X_TPI_AUDIO_SAMPLE_SIZE_16 (1 << 6) +#define SII902X_TPI_AUDIO_SAMPLE_SIZE_20 (2 << 6) +#define SII902X_TPI_AUDIO_SAMPLE_SIZE_24 (3 << 6)

+#define SII902X_TPI_AUDIO_CONFIG_BYTE4_REG 0x28

#define SII902X_INT_ENABLE 0x3c #define SII902X_INT_STATUS 0x3d #define SII902X_HOTPLUG_EVENT BIT(0) @@ -81,6 +155,16 @@

#define SII902X_REG_TPI_RQB 0xc7

+/* Indirect internal register access */ +#define SII902X_IND_SET_PAGE 0xbc +#define SII902X_IND_OFFSET 0xbd +#define SII902X_IND_VALUE 0xbe

+#define SII902X_TPI_MISC_INFOFRAME_BASE 0xbf +#define SII902X_TPI_MISC_INFOFRAME_END 0xde +#define SII902X_TPI_MISC_INFOFRAME_SIZE \

• (SII902X_TPI_MISC_INFOFRAME_END - SII902X_TPI_MISC_INFOFRAME_BASE)

#define SII902X_I2C_BUS_ACQUISITION_TIMEOUT_MS 500

struct sii902x { @@ -90,6 +174,16 @@ struct sii902x { struct drm_connector connector; struct gpio_desc *reset_gpio; struct i2c_mux_core *i2cmux;

• /*

• * Mutex protects audio and video functions from interfering
  

• * each other, by keeping their i2c command sequences atomic.
  

• */
  

• struct mutex mutex;
• struct sii902x_audio {

• struct platform_device *pdev;
  

• struct clk *mclk;
  

• u32 i2s_fifo_sequence[4];
  

• } audio;

};

static int sii902x_read_unlocked(struct i2c_client *i2c, u8 reg, u8 *val) @@ -161,8 +255,12 @@ sii902x_connector_detect(struct drm_connector *connector, bool force) struct sii902x *sii902x = connector_to_sii902x(connector); unsigned int status;

• mutex_lock(&sii902x->mutex);

• regmap_read(sii902x->regmap, SII902X_INT_STATUS, &status);

• mutex_unlock(&sii902x->mutex);

regmap uses its own lock so we have here and in other places redundant locks.

Probably you should disable regmap locking (config->disable_locking = 1).

Makes sense. I'll add that.

...

return (status & SII902X_PLUGGED_STATUS) ? connector_status_connected : connector_status_disconnected; } @@ -184,6 +282,8 @@ static int sii902x_get_modes(struct drm_connector *connector) struct edid *edid; int num = 0, ret;

• mutex_lock(&sii902x->mutex);
• edid = drm_get_edid(connector, sii902x->i2cmux->adapter[0]); drm_connector_update_edid_property(connector, edid); if (edid) {

@@ -197,14 +297,19 @@ static int sii902x_get_modes(struct drm_connector *connector) ret = drm_display_info_set_bus_formats(&connector->display_info, &bus_format, 1); if (ret)

• return ret;
  

• goto error_out;
  
  

  ret = regmap_update_bits(sii902x->regmap, SII902X_SYS_CTRL_DATA, SII902X_SYS_CTRL_OUTPUT_MODE, output_mode); if (ret)

• return ret;
  

• goto error_out;
  

• ret = num;

+error_out:

• mutex_unlock(&sii902x->mutex);

• return num;

• return ret;

}

static enum drm_mode_status sii902x_mode_valid(struct drm_connector *connector, @@ -224,20 +329,28 @@ static void sii902x_bridge_disable(struct drm_bridge *bridge) { struct sii902x *sii902x = bridge_to_sii902x(bridge);

• mutex_lock(&sii902x->mutex);
• regmap_update_bits(sii902x->regmap, SII902X_SYS_CTRL_DATA, SII902X_SYS_CTRL_PWR_DWN, SII902X_SYS_CTRL_PWR_DWN);
• mutex_unlock(&sii902x->mutex);

}

static void sii902x_bridge_enable(struct drm_bridge *bridge) { struct sii902x *sii902x = bridge_to_sii902x(bridge);

• mutex_lock(&sii902x->mutex);
• regmap_update_bits(sii902x->regmap, SII902X_PWR_STATE_CTRL, SII902X_AVI_POWER_STATE_MSK, SII902X_AVI_POWER_STATE_D(0)); regmap_update_bits(sii902x->regmap, SII902X_SYS_CTRL_DATA, SII902X_SYS_CTRL_PWR_DWN, 0);
• mutex_unlock(&sii902x->mutex);

}

static void sii902x_bridge_mode_set(struct drm_bridge *bridge, @@ -264,26 +377,31 @@ static void sii902x_bridge_mode_set(struct drm_bridge *bridge, buf[9] = SII902X_TPI_AVI_INPUT_RANGE_AUTO | SII902X_TPI_AVI_INPUT_COLORSPACE_RGB;

• mutex_lock(&sii902x->mutex);
• ret = regmap_bulk_write(regmap, SII902X_TPI_VIDEO_DATA, buf, 10); if (ret)

• return;
  

• goto out;
  
  

  ret = drm_hdmi_avi_infoframe_from_display_mode(&frame, adj, false); if (ret < 0) { DRM_ERROR("couldn't fill AVI infoframe\n");

• return;
  

• goto out;
  

  }

  ret = hdmi_avi_infoframe_pack(&frame, buf, sizeof(buf)); if (ret < 0) { DRM_ERROR("failed to pack AVI infoframe: %d\n", ret);

• return;
  

• goto out;
  

  }

  /* Do not send the infoframe header, but keep the CRC field. */ regmap_bulk_write(regmap, SII902X_TPI_AVI_INFOFRAME, buf + HDMI_INFOFRAME_HEADER_SIZE - 1, HDMI_AVI_INFOFRAME_SIZE + 1);

+out:

• mutex_unlock(&sii902x->mutex);

}

static int sii902x_bridge_attach(struct drm_bridge *bridge) @@ -324,6 +442,330 @@ static const struct drm_bridge_funcs sii902x_bridge_funcs = { .enable = sii902x_bridge_enable, };

+static int sii902x_mute(struct sii902x *sii902x, bool mute) +{

• struct device *dev = &sii902x->i2c->dev;
• unsigned int val = mute ? SII902X_TPI_AUDIO_MUTE_ENABLE :

• SII902X_TPI_AUDIO_MUTE_DISABLE;
  

• dev_dbg(dev, "%s: %s\n", __func__, mute ? "Muted" : "Unmuted");
• return regmap_update_bits(sii902x->regmap,

• 		  SII902X_TPI_AUDIO_CONFIG_BYTE2_REG,
  

• 		  SII902X_TPI_AUDIO_MUTE_ENABLE, val);
  

+}

+static const unsigned int sii902x_mclk_div_table[] = {

• 128, 256, 384, 512, 768, 1024, 1152, 192 };

+static int sii902x_select_mclk_div(u8 *i2s_config_reg, unsigned int rate,

• 		   unsigned int mclk)
  

+{

• unsigned int div = mclk / rate;
• int distance = 100000;
• u8 i, nearest = 0;
• for (i = 0; i < ARRAY_SIZE(sii902x_mclk_div_table); i++) {

• unsigned int d = abs(div - sii902x_mclk_div_table[i]);
  

Using unsigned types in this context seems to be asking for troubles.

Why? Isn't return value of abs() by definition unsigned? Using signed integers when comparing absolute distances would seem awkward to me.

...

• if (d >= distance)
  

• 	continue;
  

• nearest = i;
  

• distance = d;
  

• if (d == 0)
  

• 	break;
  

• }
• *i2s_config_reg |= nearest << 4;
• if (distance != 0)

• return sii902x_mclk_div_table[nearest];
  

• return 0;

ret value is inconsistent, 0 in case of exact match, closest value otherwise, code will be cleaner if you return always closest match.

Then I do not have the information to print a warning if an exact match was not found. The return value is only used in that warning message, the register configuration value is always delivered trough *i2s_config_reg. I do not see any inconsistency here.

...

+}

+static const struct sii902x_sample_freq {

• u32 freq;
• u8 val;

+} sii902x_sample_freq[] = {

• { .freq = 32000, .val = SII902X_TPI_AUDIO_FREQ_32KHZ },
• { .freq = 44000, .val = SII902X_TPI_AUDIO_FREQ_44KHZ },
• { .freq = 48000, .val = SII902X_TPI_AUDIO_FREQ_48KHZ },
• { .freq = 88000, .val = SII902X_TPI_AUDIO_FREQ_88KHZ },
• { .freq = 96000, .val = SII902X_TPI_AUDIO_FREQ_96KHZ },
• { .freq = 176000, .val = SII902X_TPI_AUDIO_FREQ_176KHZ },
• { .freq = 192000, .val = SII902X_TPI_AUDIO_FREQ_192KHZ },

+};

+static int sii902x_audio_hw_params(struct device *dev, void *data,

• 		   struct hdmi_codec_daifmt *daifmt,
  

• 		   struct hdmi_codec_params *params)
  

+{

• struct sii902x *sii902x = dev_get_drvdata(dev);
• u8 i2s_config_reg = SII902X_TPI_I2S_SD_DIRECTION_MSB_FIRST;
• u8 config_byte2_reg = (SII902X_TPI_AUDIO_INTERFACE_I2S |

• 	       SII902X_TPI_AUDIO_MUTE_ENABLE |
  

• 	       SII902X_TPI_AUDIO_CODING_PCM);
  

• u8 config_byte3_reg = 0;
• u8 infoframe_buf[HDMI_INFOFRAME_SIZE(AUDIO)];
• unsigned long mclk_rate;
• int i, ret;
• if (daifmt->bit_clk_master || daifmt->frame_clk_master) {

• dev_dbg(dev, "%s: I2S master mode not supported\n", __func__);
  

• return -EINVAL;
  

• }
• switch (daifmt->fmt) {
• case HDMI_I2S:

• i2s_config_reg |= SII902X_TPI_I2S_FIRST_BIT_SHIFT_YES |
  

• 	SII902X_TPI_I2S_SD_JUSTIFY_LEFT;
  

• break;
  

• case HDMI_RIGHT_J:

• i2s_config_reg |= SII902X_TPI_I2S_SD_JUSTIFY_RIGHT;
  

• break;
  

• case HDMI_LEFT_J:

• i2s_config_reg |= SII902X_TPI_I2S_SD_JUSTIFY_LEFT;
  

• break;
  

• default:

• dev_dbg(dev, "%s: Unsupported i2s format %u\n", __func__,
  

• 	daifmt->fmt);
  

• return -EINVAL;
  

• }
• if (daifmt->bit_clk_inv)

• i2s_config_reg |= SII902X_TPI_I2S_SCK_EDGE_FALLING;
  

• else

• i2s_config_reg |= SII902X_TPI_I2S_SCK_EDGE_RISING;
  

• if (daifmt->frame_clk_inv)

• i2s_config_reg |= SII902X_TPI_I2S_WS_POLARITY_LOW;
  

• else

• i2s_config_reg |= SII902X_TPI_I2S_WS_POLARITY_HIGH;
  

• if (params->channels > 2)

• config_byte2_reg |= SII902X_TPI_AUDIO_LAYOUT_8_CHANNELS;
  

• else

• config_byte2_reg |= SII902X_TPI_AUDIO_LAYOUT_2_CHANNELS;
  

• switch (params->sample_width) {
• case 16:

• config_byte3_reg |= SII902X_TPI_AUDIO_SAMPLE_SIZE_16;
  

• break;
  

• case 20:

• config_byte3_reg |= SII902X_TPI_AUDIO_SAMPLE_SIZE_20;
  

• break;
  

• case 24:
• case 32:

• config_byte3_reg |= SII902X_TPI_AUDIO_SAMPLE_SIZE_24;
  

• break;
  

• default:

• dev_err(dev, "%s: Unsupported sample width %u\n", __func__,
  

• 	params->sample_width);
  

• return -EINVAL;
  

• }
• for (i = 0; i < ARRAY_SIZE(sii902x_sample_freq); i++) {

• if (params->sample_rate == sii902x_sample_freq[i].freq) {
  

• 	config_byte3_reg |= sii902x_sample_freq[i].val;
  

• 	break;
  

• }
  

• }
• ret = clk_prepare_enable(sii902x->audio.mclk);
• if (ret) {

• dev_err(dev, "Enabling mclk failed: %d\n", ret);
  

• return ret;
  

• }
• mclk_rate = clk_get_rate(sii902x->audio.mclk);
• ret = sii902x_select_mclk_div(&i2s_config_reg, params->sample_rate,

• 		      mclk_rate);
  

• if (ret)

• dev_dbg(dev, "Inaccurate reference clock (%ld/%d != %u)\n",
  

• 	mclk_rate, ret, params->sample_rate);
  

• mutex_lock(&sii902x->mutex);
• ret = regmap_write(sii902x->regmap,

• 	   SII902X_TPI_AUDIO_CONFIG_BYTE2_REG,
  

• 	   config_byte2_reg);
  

• if (ret < 0)

• goto out;
  

• ret = regmap_write(sii902x->regmap, SII902X_TPI_I2S_INPUT_CONFIG_REG,

• 	   i2s_config_reg);
  

• if (ret)

• goto out;
  

• for (i = 0; sii902x->audio.i2s_fifo_sequence[i] &&

•      i < ARRAY_SIZE(sii902x->audio.i2s_fifo_sequence); i++)
  

• regmap_write(sii902x->regmap,
  

• 	     SII902X_TPI_I2S_ENABLE_MAPPING_REG,
  

• 	     sii902x->audio.i2s_fifo_sequence[i]);
  

• ret = regmap_write(sii902x->regmap, SII902X_TPI_AUDIO_CONFIG_BYTE3_REG,

• 	   config_byte3_reg);
  

• if (ret)

• goto out;
  

• ret = regmap_bulk_write(sii902x->regmap, SII902X_TPI_I2S_STRM_HDR_BASE,

• 		params->iec.status,
  

• 		min((size_t) SII902X_TPI_I2S_STRM_HDR_SIZE,
  

• 		    sizeof(params->iec.status)));
  

• if (ret)

• goto out;
  

• ret = hdmi_audio_infoframe_pack(&params->cea, infoframe_buf,

• 			sizeof(infoframe_buf));
  

• if (ret < 0) {

• dev_err(dev, "%s: Failed to pack audio infoframe: %d\n",
  

• 	__func__, ret);
  

• goto out;
  

• }
• ret = regmap_bulk_write(sii902x->regmap,

• 		SII902X_TPI_MISC_INFOFRAME_BASE,
  

• 		infoframe_buf,
  

• 		min(ret, SII902X_TPI_MISC_INFOFRAME_SIZE));
  

• if (ret)

• goto out;
  

• /* Decode Level 0 Packets */
• ret = regmap_write(sii902x->regmap, SII902X_IND_SET_PAGE, 0x02);
• if (ret)

• goto out;
  

• ret = regmap_write(sii902x->regmap, SII902X_IND_OFFSET, 0x24);
• if (ret)

• goto out;
  

• ret = regmap_write(sii902x->regmap, SII902X_IND_VALUE, 0x02);
• if (ret)

• goto out;
  

• dev_dbg(dev, "%s: hdmi audio enabled\n", __func__);

+out:

• mutex_unlock(&sii902x->mutex);
• if (ret) {

• clk_disable_unprepare(sii902x->audio.mclk);
  

• dev_err(dev, "%s: hdmi audio enable failed: %d\n", __func__,
  

• 	ret);
  

• }
• return ret;

+}

+static void sii902x_audio_shutdown(struct device *dev, void *data) +{

• struct sii902x *sii902x = dev_get_drvdata(dev);
• mutex_lock(&sii902x->mutex);
• regmap_write(sii902x->regmap, SII902X_TPI_AUDIO_CONFIG_BYTE2_REG,

•      SII902X_TPI_AUDIO_INTERFACE_DISABLE);
  

• mutex_unlock(&sii902x->mutex);
• clk_disable_unprepare(sii902x->audio.mclk);

+}

+int sii902x_audio_digital_mute(struct device *dev, void *data, bool enable) +{

• struct sii902x *sii902x = dev_get_drvdata(dev);
• mutex_lock(&sii902x->mutex);
• sii902x_mute(sii902x, enable);
• mutex_unlock(&sii902x->mutex);
• return 0;

+}

+static int sii902x_audio_get_eld(struct device *dev, void *data,

• 		 uint8_t *buf, size_t len)
  

+{

• struct sii902x *sii902x = dev_get_drvdata(dev);
• mutex_lock(&sii902x->mutex);
• memcpy(buf, sii902x->connector.eld,

•       min(sizeof(sii902x->connector.eld), len));
  

I am not familiar with audio stuff, so forgive my ignorance :)

What happens when this or other audio callbacks is called:

1. before sth is plugged in connector.

...

2. after unplug.

3. plug/un-plug happens between these calls.

The audio side calls this at the time of audio playback request. If there is no valid eld at that time, the playback request fails. The eld is only used at the playback start time, never after it.

When an audio playback is running it we do not do anything to until the playback is stopped. E.g. if plug/un-plug happens we just keep playing with the original configuration (my first version had an abort call back to abort playback in unplug event, but that was refused in the reviews).

If the cable is never plugged again, or the new display does not have audio support, the i2s just keeps banging the bits to dev null and audio data keeps drainging away. When cable is again plugged to audio capable display, it continues playing there (and it never stopped in between.

This comes closest to already established behaviour with already existing HDMI audio implementations. This is also usually the preferred behavior, because resebles how video stream playback behaves.

I know very well that this is not the perfect solution. The perfect solution would have the abort callback there, and some mechanism above that to deal with the audio playback being aborted and the device becoming available again. This would require co-operation from userspace. However, the world is not ready and this is a best effort implementation.

Also I do not see hotplug/unplug notification mechanism to audio subsystem. It looks suspicious.

Yes, as mentioned above, I had it in my first version of hdmi-codec, but it was never accepted to mainline. However, in practice this has not been a problem. The HDMI audio implementation on the encoder chips I have seen is usually quite independent from the video side workings.

Regards

Andrzej

Thanks, Jyri

...

• mutex_unlock(&sii902x->mutex);
• return 0;

+}

+static const struct hdmi_codec_ops sii902x_audio_codec_ops = {

• .hw_params = sii902x_audio_hw_params,
• .audio_shutdown = sii902x_audio_shutdown,
• .digital_mute = sii902x_audio_digital_mute,
• .get_eld = sii902x_audio_get_eld,

+};

+static int sii902x_audio_codec_init(struct sii902x *sii902x,

• 		    struct device *dev)
  

+{

• static const u8 audio_fifo_id[] = {

• SII902X_TPI_I2S_CONFIG_FIFO0,
  

• SII902X_TPI_I2S_CONFIG_FIFO1,
  

• SII902X_TPI_I2S_CONFIG_FIFO2,
  

• SII902X_TPI_I2S_CONFIG_FIFO3,
  

• };
• static const u8 i2s_lane_id[] = {

• SII902X_TPI_I2S_SELECT_SD0,
  

• SII902X_TPI_I2S_SELECT_SD1,
  

• SII902X_TPI_I2S_SELECT_SD2,
  

• SII902X_TPI_I2S_SELECT_SD3,
  

• };
• struct hdmi_codec_pdata codec_data = {

• .ops = &sii902x_audio_codec_ops,
  

• .i2s = 1, /* Only i2s support for now. */
  

• .spdif = 0,
  

• .max_i2s_channels = 0,
  

• };
• u8 lanes[4];
• u32 num_lanes, i;
• num_lanes = of_property_read_variable_u8_array(dev->of_node,

• 				       "sil,i2s-data-lanes",
  

• 				       lanes, 1,
  

• 				       ARRAY_SIZE(lanes));
  

• if (num_lanes < 0) {

• if (num_lanes == -EINVAL)
  

• 	dev_dbg(dev,
  

• 		"%s: No \"sil,i2s-data-lanes\", no audio\n",
  

• 		__func__);
  

• else
  

• 	dev_err(dev,
  

• 		"%s: Error gettin \"sil,i2s-data-lanes\": %d\n",
  

• 		__func__, num_lanes);
  

• return 0;
  

• }
• codec_data.max_i2s_channels = 2 * num_lanes;
• for (i = 0; i < num_lanes; i++)

• sii902x->audio.i2s_fifo_sequence[i] |= audio_fifo_id[i] |
  

• 	i2s_lane_id[lanes[i]] |	SII902X_TPI_I2S_FIFO_ENABLE;
  

• if (IS_ERR(sii902x->audio.mclk)) {

• dev_err(dev, "%s: No clock (audio mclk) found: %ld\n",
  

• 	__func__, PTR_ERR(sii902x->audio.mclk));
  

• return 0;
  

• }
• sii902x->audio.pdev = platform_device_register_data(

• dev, HDMI_CODEC_DRV_NAME, PLATFORM_DEVID_AUTO,
  

• &codec_data, sizeof(codec_data));
  

• return PTR_ERR_OR_ZERO(sii902x->audio.pdev);

+}

static const struct regmap_range sii902x_volatile_ranges[] = { { .range_min = 0, .range_max = 0xff }, }; @@ -336,6 +778,7 @@ static const struct regmap_access_table sii902x_volatile_table = { static const struct regmap_config sii902x_regmap_config = { .reg_bits = 8, .val_bits = 8,

• .max_register = SII902X_TPI_MISC_INFOFRAME_END, .volatile_table = &sii902x_volatile_table, .cache_type = REGCACHE_NONE,

}; @@ -508,6 +951,8 @@ static int sii902x_probe(struct i2c_client *client, return PTR_ERR(sii902x->reset_gpio); }

• mutex_init(&sii902x->mutex);

• sii902x_reset(sii902x);

  ret = regmap_write(sii902x->regmap, SII902X_REG_TPI_RQB, 0x0);

@@ -548,6 +993,8 @@ static int sii902x_probe(struct i2c_client *client, sii902x->bridge.timings = &default_sii902x_timings; drm_bridge_add(&sii902x->bridge);

• sii902x_audio_codec_init(sii902x, dev);

• i2c_set_clientdata(client, sii902x);

  sii902x->i2cmux = i2c_mux_alloc(client->adapter, dev,