[PATCH RFC v2 0/7] drm: add DRM HDMI Codec framework

[PATCH RFC v2 0/7] drm: add DRM HDMI Codec framework

[Dmitry Baryshkov]

While porting lt9611 DSI-to-HDMI bridge driver to use HDMI Connector
framework, I stumbled upon an issue while handling the Audio InfoFrames.
The HDMI codec callbacks weren't receiving the drm_atomic_state, so
there was no simple way to get the drm_connector that stayed at the end
of the bridge chain. At the same point the drm_hdmi_connector functions
expected to get drm_connector instance.

While looking for a way to solve the issue, I stumbled upon several
deficiencies in existing hdmi_codec_ops implementations. Only few of the
implementations were able to handle codec's 'plugged' callback. One
third of the drivers didn't implement the get_eld() callback.

Most of the issues can be solved if drm_connector handles
hdmi-audio-codec on its own, delegating functionality to the actual
implementation, be it a driver that implements drm_connector or
drm_bridge.

Implement such high-level framework, adding proper support for Audio
InfoFrame generation to the LT9611 driver.

Several design decisions to be kept in mind:

- drm_connector_hdmi_codec is kept as simple as possible. It implements
  generic functionality (ELD, hotplug, registration).

- drm_hdmi_connector sets up HDMI codec device if the connector
  is setup correspondingly (either I2S or S/PDIF is marked as
  supported).

- drm_bridge_connector provides a way to link HDMI audio codec
  funcionality in the drm_bridge with the drm_connector_hdmi_codec
  framework.

- It might be worth reverting the no_i2s_capture / no_spdif_capture
  bits. Only TDA889x driver sets them, while it's safe to assume that
  most of HDMI / DP devices do not support ARC / capture. I think the
  drivers should opt-in capture support rather than having to opt-out of
  it.

This series is in the RFC stage, so some bits are underdocumented.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
Changes in v2:
- Use drm_atomic_get_old_connector_for_encoder in atomic_disable() to
  prevent it from crashing
- Reworked HDMI codec init/exit, removing drmm_ calls (Maxime)
- Drafted the helper to be called from .detect_ctx() that performs HDMI
  Connector maintenance duties (Maxime)
- Moved no_capture_mute to struct hdmi_codec_pdata
- Link to v1: https://lore.kernel.org/r/20240615-drm-bridge-hdmi-connector-v1-0-d59fc7865ab2@linaro.org

---
Dmitry Baryshkov (7):
      ASoC: hdmi-codec: pass data to get_dai_id too
      ASoC: hdmi-codec: move no_capture_mute to struct hdmi_codec_pdata
      drm/connector: implement generic HDMI codec helpers
      drm/bridge: connector: add support for HDMI codec framework
      drm/bridge: lt9611: switch to using the DRM HDMI codec framework
      drm/display/hdmi: implement connector update functions
      drm/bridge_connector: hook __drm_atomic_helper_connector_hdmi_update_edid()

 drivers/gpu/drm/Makefile                           |   1 +
 drivers/gpu/drm/bridge/adv7511/adv7511_audio.c     |   3 +-
 drivers/gpu/drm/bridge/analogix/anx7625.c          |   3 +-
 drivers/gpu/drm/bridge/ite-it66121.c               |   2 +-
 drivers/gpu/drm/bridge/lontium-lt9611.c            | 170 ++++++++-----------
 drivers/gpu/drm/bridge/lontium-lt9611uxc.c         |   3 +-
 drivers/gpu/drm/bridge/sii902x.c                   |   5 +-
 .../gpu/drm/bridge/synopsys/dw-hdmi-i2s-audio.c    |   3 +-
 drivers/gpu/drm/display/drm_bridge_connector.c     | 160 ++++++++++++++++--
 drivers/gpu/drm/display/drm_hdmi_state_helper.c    |  56 +++++++
 drivers/gpu/drm/drm_connector.c                    |  10 ++
 drivers/gpu/drm/drm_connector_hdmi_codec.c         | 186 +++++++++++++++++++++
 drivers/gpu/drm/drm_internal.h                     |   5 +
 drivers/gpu/drm/exynos/exynos_hdmi.c               |   2 +-
 drivers/gpu/drm/i2c/tda998x_drv.c                  |   2 +-
 drivers/gpu/drm/mediatek/mtk_dp.c                  |   2 +-
 drivers/gpu/drm/mediatek/mtk_hdmi.c                |   2 +-
 drivers/gpu/drm/rockchip/cdn-dp-core.c             |   2 +-
 drivers/gpu/drm/sti/sti_hdmi.c                     |   2 +-
 include/drm/display/drm_hdmi_state_helper.h        |   4 +
 include/drm/drm_bridge.h                           |  23 +++
 include/drm/drm_connector.h                        |  80 +++++++++
 include/sound/hdmi-codec.h                         |   7 +-
 sound/soc/codecs/hdmi-codec.c                      |   4 +-
 24 files changed, 601 insertions(+), 136 deletions(-)
---
base-commit: f9f24ca362a4d84dd8aeb4b8f3ec28cb6c43dd06
change-id: 20240530-drm-bridge-hdmi-connector-9b0f6725973e

Best regards,
-- 
Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

[PATCH RFC v2 1/7] ASoC: hdmi-codec: pass data to get_dai_id too

[Dmitry Baryshkov]

The upcoming DRM connector HDMI codec implementation is going to use
codec-specific data in the .get_dai_id to get drm_connector. Pass data
to the callback, as it is done with other hdmi_codec_ops callbacks.

Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/bridge/adv7511/adv7511_audio.c      | 3 ++-
 drivers/gpu/drm/bridge/analogix/anx7625.c           | 3 ++-
 drivers/gpu/drm/bridge/lontium-lt9611.c             | 3 ++-
 drivers/gpu/drm/bridge/lontium-lt9611uxc.c          | 3 ++-
 drivers/gpu/drm/bridge/sii902x.c                    | 3 ++-
 drivers/gpu/drm/bridge/synopsys/dw-hdmi-i2s-audio.c | 3 ++-
 include/sound/hdmi-codec.h                          | 3 ++-
 sound/soc/codecs/hdmi-codec.c                       | 2 +-
 8 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_audio.c b/drivers/gpu/drm/bridge/adv7511/adv7511_audio.c
index 61f4a38e7d2bf6905683cbc9e762b28ecc999d05..51fb9a574b4e28450b2598a92e2930ace5128b71 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_audio.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_audio.c
@@ -204,7 +204,8 @@ static void audio_shutdown(struct device *dev, void *data)
 }
 
 static int adv7511_hdmi_i2s_get_dai_id(struct snd_soc_component *component,
-					struct device_node *endpoint)
+					struct device_node *endpoint,
+					void *data)
 {
 	struct of_endpoint of_ep;
 	int ret;
diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index a2675b121fe44b96945f34215fd900f35bfde43a..926437346b6c9a651d495faf25162cac7407d30d 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -1952,7 +1952,8 @@ static void anx7625_audio_shutdown(struct device *dev, void *data)
 }
 
 static int anx7625_hdmi_i2s_get_dai_id(struct snd_soc_component *component,
-				       struct device_node *endpoint)
+				       struct device_node *endpoint,
+				       void *data)
 {
 	struct of_endpoint of_ep;
 	int ret;
diff --git a/drivers/gpu/drm/bridge/lontium-lt9611.c b/drivers/gpu/drm/bridge/lontium-lt9611.c
index 1b31fdebe164063e6f3972fdf8a5801ef4c35c4e..4fa0dfc5539a5786278221f7c13b6473ab320a9a 100644
--- a/drivers/gpu/drm/bridge/lontium-lt9611.c
+++ b/drivers/gpu/drm/bridge/lontium-lt9611.c
@@ -1059,7 +1059,8 @@ static void lt9611_audio_shutdown(struct device *dev, void *data)
 }
 
 static int lt9611_hdmi_i2s_get_dai_id(struct snd_soc_component *component,
-				      struct device_node *endpoint)
+				      struct device_node *endpoint,
+				      void *data)
 {
 	struct of_endpoint of_ep;
 	int ret;
diff --git a/drivers/gpu/drm/bridge/lontium-lt9611uxc.c b/drivers/gpu/drm/bridge/lontium-lt9611uxc.c
index 4d1d40e1f1b4d144f4aa9de7b83bedf13dfa4436..fd26aa36b15b8c0d3859f7ef488a87573eea8507 100644
--- a/drivers/gpu/drm/bridge/lontium-lt9611uxc.c
+++ b/drivers/gpu/drm/bridge/lontium-lt9611uxc.c
@@ -522,7 +522,8 @@ static void lt9611uxc_audio_shutdown(struct device *dev, void *data)
 }
 
 static int lt9611uxc_hdmi_i2s_get_dai_id(struct snd_soc_component *component,
-					 struct device_node *endpoint)
+					 struct device_node *endpoint,
+					 void *data)
 {
 	struct of_endpoint of_ep;
 	int ret;
diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index 9be9cc5b902594ebe6e1ac29ab8684623e336796..f0be803cc2274ca2199ed7661cf752b0a91434b6 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -815,7 +815,8 @@ static int sii902x_audio_get_eld(struct device *dev, void *data,
 }
 
 static int sii902x_audio_get_dai_id(struct snd_soc_component *component,
-				    struct device_node *endpoint)
+				    struct device_node *endpoint,
+				    void *data)
 {
 	struct of_endpoint of_ep;
 	int ret;
diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-i2s-audio.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-i2s-audio.c
index 26c187d20d973dc65801a3baa59ecf57d20072eb..86c412e9cbc80bb82bad5db3aa0263a7acd9c2d7 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-i2s-audio.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-i2s-audio.c
@@ -148,7 +148,8 @@ static int dw_hdmi_i2s_get_eld(struct device *dev, void *data, uint8_t *buf,
 }
 
 static int dw_hdmi_i2s_get_dai_id(struct snd_soc_component *component,
-				  struct device_node *endpoint)
+				  struct device_node *endpoint,
+				  void *data)
 {
 	struct of_endpoint of_ep;
 	int ret;
diff --git a/include/sound/hdmi-codec.h b/include/sound/hdmi-codec.h
index 5e1a9eafd10f5d4f831abbb6f4c0fff661909584..b3407b47b4a7878532ecf3b08eeecd443d6fdb07 100644
--- a/include/sound/hdmi-codec.h
+++ b/include/sound/hdmi-codec.h
@@ -105,7 +105,8 @@ struct hdmi_codec_ops {
 	 * Optional
 	 */
 	int (*get_dai_id)(struct snd_soc_component *comment,
-			  struct device_node *endpoint);
+			  struct device_node *endpoint,
+			  void *data);
 
 	/*
 	 * Hook callback function to handle connector plug event.
diff --git a/sound/soc/codecs/hdmi-codec.c b/sound/soc/codecs/hdmi-codec.c
index 74caae52e1273fda45ab8dd079ae800827f0231f..abd7c9b0fda9ee6fa6c4efde1f583af667716611 100644
--- a/sound/soc/codecs/hdmi-codec.c
+++ b/sound/soc/codecs/hdmi-codec.c
@@ -981,7 +981,7 @@ static int hdmi_of_xlate_dai_id(struct snd_soc_component *component,
 	int ret = -ENOTSUPP; /* see snd_soc_get_dai_id() */
 
 	if (hcp->hcd.ops->get_dai_id)
-		ret = hcp->hcd.ops->get_dai_id(component, endpoint);
+		ret = hcp->hcd.ops->get_dai_id(component, endpoint, hcp->hcd.data);
 
 	return ret;
 }

-- 
2.39.5

[PATCH RFC v2 2/7] ASoC: hdmi-codec: move no_capture_mute to struct hdmi_codec_pdata

[Dmitry Baryshkov]

The no_capture_mute flag might differ from platform to platform,
especially in the case of the wrapping implementations, like the
upcoming DRM HDMI Codec framework. Move the flag next to all other flags
in struct hdmi_codec_pdata.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/bridge/ite-it66121.c   | 2 +-
 drivers/gpu/drm/bridge/sii902x.c       | 2 +-
 drivers/gpu/drm/exynos/exynos_hdmi.c   | 2 +-
 drivers/gpu/drm/i2c/tda998x_drv.c      | 2 +-
 drivers/gpu/drm/mediatek/mtk_dp.c      | 2 +-
 drivers/gpu/drm/mediatek/mtk_hdmi.c    | 2 +-
 drivers/gpu/drm/rockchip/cdn-dp-core.c | 2 +-
 drivers/gpu/drm/sti/sti_hdmi.c         | 2 +-
 include/sound/hdmi-codec.h             | 4 +---
 sound/soc/codecs/hdmi-codec.c          | 2 +-
 10 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/bridge/ite-it66121.c b/drivers/gpu/drm/bridge/ite-it66121.c
index 35ae3f0e8f51f768229e055a086b53a419ffcd9f..98669470d1e955fef36bb4592795fed6ca97139c 100644
--- a/drivers/gpu/drm/bridge/ite-it66121.c
+++ b/drivers/gpu/drm/bridge/ite-it66121.c
@@ -1464,7 +1464,6 @@ static const struct hdmi_codec_ops it66121_audio_codec_ops = {
 	.audio_shutdown = it66121_audio_shutdown,
 	.mute_stream = it66121_audio_mute,
 	.get_eld = it66121_audio_get_eld,
-	.no_capture_mute = 1,
 };
 
 static int it66121_audio_codec_init(struct it66121_ctx *ctx, struct device *dev)
@@ -1474,6 +1473,7 @@ static int it66121_audio_codec_init(struct it66121_ctx *ctx, struct device *dev)
 		.i2s = 1, /* Only i2s support for now */
 		.spdif = 0,
 		.max_i2s_channels = 8,
+		.no_capture_mute = 1,
 	};
 
 	dev_dbg(dev, "%s\n", __func__);
diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index f0be803cc2274ca2199ed7661cf752b0a91434b6..5248676b0036a7e8f2142bd2f099c36efb529471 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -841,7 +841,6 @@ static const struct hdmi_codec_ops sii902x_audio_codec_ops = {
 	.mute_stream = sii902x_audio_mute,
 	.get_eld = sii902x_audio_get_eld,
 	.get_dai_id = sii902x_audio_get_dai_id,
-	.no_capture_mute = 1,
 };
 
 static int sii902x_audio_codec_init(struct sii902x *sii902x,
@@ -864,6 +863,7 @@ static int sii902x_audio_codec_init(struct sii902x *sii902x,
 		.i2s = 1, /* Only i2s support for now. */
 		.spdif = 0,
 		.max_i2s_channels = 0,
+		.no_capture_mute = 1,
 	};
 	u8 lanes[4];
 	int num_lanes, i;
diff --git a/drivers/gpu/drm/exynos/exynos_hdmi.c b/drivers/gpu/drm/exynos/exynos_hdmi.c
index c9d4b9146df95bb46cb6bea4849c331616c2b463..2a74396ac846dc34d87fadea700c387d597ba307 100644
--- a/drivers/gpu/drm/exynos/exynos_hdmi.c
+++ b/drivers/gpu/drm/exynos/exynos_hdmi.c
@@ -1658,7 +1658,6 @@ static const struct hdmi_codec_ops audio_codec_ops = {
 	.audio_shutdown = hdmi_audio_shutdown,
 	.mute_stream = hdmi_audio_mute,
 	.get_eld = hdmi_audio_get_eld,
-	.no_capture_mute = 1,
 };
 
 static int hdmi_register_audio_device(struct hdmi_context *hdata)
@@ -1667,6 +1666,7 @@ static int hdmi_register_audio_device(struct hdmi_context *hdata)
 		.ops = &audio_codec_ops,
 		.max_i2s_channels = 6,
 		.i2s = 1,
+		.no_capture_mute = 1,
 	};
 
 	hdata->audio.pdev = platform_device_register_data(
diff --git a/drivers/gpu/drm/i2c/tda998x_drv.c b/drivers/gpu/drm/i2c/tda998x_drv.c
index 2160f05bbd16d2346e27365e5549b75ad26fdcb9..10a4195d667ff577183788f8fc7ca806660e2b9c 100644
--- a/drivers/gpu/drm/i2c/tda998x_drv.c
+++ b/drivers/gpu/drm/i2c/tda998x_drv.c
@@ -1165,7 +1165,6 @@ static const struct hdmi_codec_ops audio_codec_ops = {
 	.audio_shutdown = tda998x_audio_shutdown,
 	.mute_stream = tda998x_audio_mute_stream,
 	.get_eld = tda998x_audio_get_eld,
-	.no_capture_mute = 1,
 };
 
 static int tda998x_audio_codec_init(struct tda998x_priv *priv,
@@ -1176,6 +1175,7 @@ static int tda998x_audio_codec_init(struct tda998x_priv *priv,
 		.max_i2s_channels = 2,
 		.no_i2s_capture = 1,
 		.no_spdif_capture = 1,
+		.no_capture_mute = 1,
 	};
 
 	if (priv->audio_port_enable[AUDIO_ROUTE_I2S])
diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c
index f0f6f402994a7be7e3faee68d66bdb25888ab768..b401246b8f884b9885ece7aaac23a4de2826fb0a 100644
--- a/drivers/gpu/drm/mediatek/mtk_dp.c
+++ b/drivers/gpu/drm/mediatek/mtk_dp.c
@@ -2532,7 +2532,6 @@ static const struct hdmi_codec_ops mtk_dp_audio_codec_ops = {
 	.audio_shutdown = mtk_dp_audio_shutdown,
 	.get_eld = mtk_dp_audio_get_eld,
 	.hook_plugged_cb = mtk_dp_audio_hook_plugged_cb,
-	.no_capture_mute = 1,
 };
 
 static int mtk_dp_register_audio_driver(struct device *dev)
@@ -2543,6 +2542,7 @@ static int mtk_dp_register_audio_driver(struct device *dev)
 		.max_i2s_channels = 8,
 		.i2s = 1,
 		.data = mtk_dp,
+		.no_capture_mute = 1,
 	};
 
 	mtk_dp->audio_pdev = platform_device_register_data(dev,
diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c b/drivers/gpu/drm/mediatek/mtk_hdmi.c
index 7687f673964ec7df0d76328a43ed76d71b192350..a4b144b3bda8362a6c6c303723c6d3eef9ca338e 100644
--- a/drivers/gpu/drm/mediatek/mtk_hdmi.c
+++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c
@@ -1660,7 +1660,6 @@ static const struct hdmi_codec_ops mtk_hdmi_audio_codec_ops = {
 	.mute_stream = mtk_hdmi_audio_mute,
 	.get_eld = mtk_hdmi_audio_get_eld,
 	.hook_plugged_cb = mtk_hdmi_audio_hook_plugged_cb,
-	.no_capture_mute = 1,
 };
 
 static int mtk_hdmi_register_audio_driver(struct device *dev)
@@ -1671,6 +1670,7 @@ static int mtk_hdmi_register_audio_driver(struct device *dev)
 		.max_i2s_channels = 2,
 		.i2s = 1,
 		.data = hdmi,
+		.no_capture_mute = 1,
 	};
 	struct platform_device *pdev;
 
diff --git a/drivers/gpu/drm/rockchip/cdn-dp-core.c b/drivers/gpu/drm/rockchip/cdn-dp-core.c
index b04538907f956cbf7732c9177c477951eaa32276..a1229d7fd57104c5c1f31b5b64d66e8249358d52 100644
--- a/drivers/gpu/drm/rockchip/cdn-dp-core.c
+++ b/drivers/gpu/drm/rockchip/cdn-dp-core.c
@@ -885,7 +885,6 @@ static const struct hdmi_codec_ops audio_codec_ops = {
 	.mute_stream = cdn_dp_audio_mute_stream,
 	.get_eld = cdn_dp_audio_get_eld,
 	.hook_plugged_cb = cdn_dp_audio_hook_plugged_cb,
-	.no_capture_mute = 1,
 };
 
 static int cdn_dp_audio_codec_init(struct cdn_dp_device *dp,
@@ -896,6 +895,7 @@ static int cdn_dp_audio_codec_init(struct cdn_dp_device *dp,
 		.spdif = 1,
 		.ops = &audio_codec_ops,
 		.max_i2s_channels = 8,
+		.no_capture_mute = 1,
 	};
 
 	dp->audio_pdev = platform_device_register_data(
diff --git a/drivers/gpu/drm/sti/sti_hdmi.c b/drivers/gpu/drm/sti/sti_hdmi.c
index 847470f747c0efad61c2ebdc3fb3746a7a13a863..dfb8e2887fae10cf3275e8f8427f39279982c5e6 100644
--- a/drivers/gpu/drm/sti/sti_hdmi.c
+++ b/drivers/gpu/drm/sti/sti_hdmi.c
@@ -1235,7 +1235,6 @@ static const struct hdmi_codec_ops audio_codec_ops = {
 	.audio_shutdown = hdmi_audio_shutdown,
 	.mute_stream = hdmi_audio_mute,
 	.get_eld = hdmi_audio_get_eld,
-	.no_capture_mute = 1,
 };
 
 static int sti_hdmi_register_audio_driver(struct device *dev,
@@ -1245,6 +1244,7 @@ static int sti_hdmi_register_audio_driver(struct device *dev,
 		.ops = &audio_codec_ops,
 		.max_i2s_channels = 8,
 		.i2s = 1,
+		.no_capture_mute = 1,
 	};
 
 	DRM_DEBUG_DRIVER("\n");
diff --git a/include/sound/hdmi-codec.h b/include/sound/hdmi-codec.h
index b3407b47b4a7878532ecf3b08eeecd443d6fdb07..b220072cfa1baf503efbe2d530d7e8392dc16603 100644
--- a/include/sound/hdmi-codec.h
+++ b/include/sound/hdmi-codec.h
@@ -115,9 +115,6 @@ struct hdmi_codec_ops {
 	int (*hook_plugged_cb)(struct device *dev, void *data,
 			       hdmi_codec_plugged_cb fn,
 			       struct device *codec_dev);
-
-	/* bit field */
-	unsigned int no_capture_mute:1;
 };
 
 /* HDMI codec initalization data */
@@ -129,6 +126,7 @@ struct hdmi_codec_pdata {
 	uint spdif:1;
 	uint no_spdif_playback:1;
 	uint no_spdif_capture:1;
+	uint no_capture_mute:1;
 	int max_i2s_channels;
 	void *data;
 };
diff --git a/sound/soc/codecs/hdmi-codec.c b/sound/soc/codecs/hdmi-codec.c
index abd7c9b0fda9ee6fa6c4efde1f583af667716611..e8aac8069587785bcd2bd09b5f9e0140304fb8fb 100644
--- a/sound/soc/codecs/hdmi-codec.c
+++ b/sound/soc/codecs/hdmi-codec.c
@@ -700,7 +700,7 @@ static int hdmi_codec_mute(struct snd_soc_dai *dai, int mute, int direction)
 	 */
 	if (hcp->hcd.ops->mute_stream &&
 	    (direction == SNDRV_PCM_STREAM_PLAYBACK ||
-	     !hcp->hcd.ops->no_capture_mute))
+	     !hcp->hcd.no_capture_mute))
 		return hcp->hcd.ops->mute_stream(dai->dev->parent,
 						 hcp->hcd.data,
 						 mute, direction);

-- 
2.39.5

Re: [PATCH RFC v2 2/7] ASoC: hdmi-codec: move no_capture_mute to struct hdmi_codec_pdata

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 348 bytes --]

On Fri, Nov 01, 2024 at 12:19:03PM +0200, Dmitry Baryshkov wrote:
> The no_capture_mute flag might differ from platform to platform,
> especially in the case of the wrapping implementations, like the
> upcoming DRM HDMI Codec framework. Move the flag next to all other flags
> in struct hdmi_codec_pdata.

Acked-by: Mark Brown <broonie@kernel.org>

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

[PATCH RFC v2 3/7] drm/connector: implement generic HDMI codec helpers

[Dmitry Baryshkov]

Several DRM drivers implement HDMI codec support (despite its name it
applies to both HDMI and DisplayPort drivers). Implement generic
framework to be used by these drivers. This removes a requirement to
implement get_eld() callback and provides default implementation for
codec's plug handling.

The framework is integrated with the DRM HDMI Connector framework, but
can be used by DisplayPort drivers.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/Makefile                   |   1 +
 drivers/gpu/drm/drm_connector.c            |  10 ++
 drivers/gpu/drm/drm_connector_hdmi_codec.c | 186 +++++++++++++++++++++++++++++
 drivers/gpu/drm/drm_internal.h             |   5 +
 include/drm/drm_connector.h                |  80 +++++++++++++
 5 files changed, 282 insertions(+)

diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 463afad1b5ca6275e61223adc8ca036c3d4d6b03..ab5b052ad5229229ac46e3804be77dd1d1680f58 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -42,6 +42,7 @@ drm-y := \
 	drm_cache.o \
 	drm_color_mgmt.o \
 	drm_connector.o \
+	drm_connector_hdmi_codec.o \
 	drm_crtc.o \
 	drm_displayid.o \
 	drm_drv.o \
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index fc35f47e2849ed6786d6223ac9c69e1c359fc648..1a155a9fb401f687e5a88e72faca1e81d944b6d2 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -279,6 +279,7 @@ static int __drm_connector_init(struct drm_device *dev,
 	mutex_init(&connector->mutex);
 	mutex_init(&connector->edid_override_mutex);
 	mutex_init(&connector->hdmi.infoframes.lock);
+	mutex_init(&connector->hdmi_codec.lock);
 	connector->edid_blob_ptr = NULL;
 	connector->epoch_counter = 0;
 	connector->tile_blob_ptr = NULL;
@@ -533,6 +534,12 @@ int drmm_connector_hdmi_init(struct drm_device *dev,
 
 	connector->hdmi.funcs = hdmi_funcs;
 
+	if (connector->hdmi_codec.i2s || connector->hdmi_codec.spdif) {
+		ret = drm_connector_hdmi_codec_init(connector);
+		if (ret)
+			return ret;
+	}
+
 	return 0;
 }
 EXPORT_SYMBOL(drmm_connector_hdmi_init);
@@ -631,6 +638,8 @@ void drm_connector_cleanup(struct drm_connector *connector)
 		    DRM_CONNECTOR_REGISTERED))
 		drm_connector_unregister(connector);
 
+	drm_connector_hdmi_codec_cleanup(connector);
+
 	if (connector->privacy_screen) {
 		drm_privacy_screen_put(connector->privacy_screen);
 		connector->privacy_screen = NULL;
@@ -669,6 +678,7 @@ void drm_connector_cleanup(struct drm_connector *connector)
 		connector->funcs->atomic_destroy_state(connector,
 						       connector->state);
 
+	mutex_destroy(&connector->hdmi_codec.lock);
 	mutex_destroy(&connector->hdmi.infoframes.lock);
 	mutex_destroy(&connector->mutex);
 
diff --git a/drivers/gpu/drm/drm_connector_hdmi_codec.c b/drivers/gpu/drm/drm_connector_hdmi_codec.c
new file mode 100644
index 0000000000000000000000000000000000000000..cec727d3fc1493684e954195264b1a5d85a7a2ff
--- /dev/null
+++ b/drivers/gpu/drm/drm_connector_hdmi_codec.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright (c) 2024 Linaro Ltd
+ */
+
+#include <linux/mutex.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+
+#include <drm/drm_connector.h>
+#include <drm/drm_device.h>
+
+#include <sound/hdmi-codec.h>
+
+#include "drm_internal.h"
+
+static int drm_connector_hdmi_codec_audio_startup(struct device *dev, void *data)
+{
+	struct drm_connector *connector = data;
+	const struct drm_connector_hdmi_codec_funcs *funcs =
+		connector->hdmi.funcs->codec_funcs;
+
+	if (funcs->audio_startup)
+		return funcs->audio_startup(connector);
+
+	return 0;
+}
+
+static int drm_connector_hdmi_codec_prepare(struct device *dev, void *data,
+					    struct hdmi_codec_daifmt *fmt,
+					    struct hdmi_codec_params *hparms)
+{
+	struct drm_connector *connector = data;
+	const struct drm_connector_hdmi_codec_funcs *funcs =
+		connector->hdmi.funcs->codec_funcs;
+
+	return funcs->prepare(connector, fmt, hparms);
+}
+
+static void drm_connector_hdmi_codec_audio_shutdown(struct device *dev, void *data)
+{
+	struct drm_connector *connector = data;
+	const struct drm_connector_hdmi_codec_funcs *funcs =
+		connector->hdmi.funcs->codec_funcs;
+
+	return funcs->audio_shutdown(connector);
+}
+
+static int drm_connector_hdmi_codec_mute_stream(struct device *dev, void *data,
+						bool enable, int direction)
+{
+	struct drm_connector *connector = data;
+	const struct drm_connector_hdmi_codec_funcs *funcs =
+		connector->hdmi.funcs->codec_funcs;
+
+	if (funcs->mute_stream)
+		return funcs->mute_stream(connector, enable, direction);
+
+	return -ENOTSUPP;
+}
+
+static int drm_connector_hdmi_codec_get_dai_id(struct snd_soc_component *comment,
+		  struct device_node *endpoint,
+		  void *data)
+{
+	struct drm_connector *connector = data;
+	struct of_endpoint of_ep;
+	int ret;
+
+	if (connector->hdmi_codec.sound_dai_port < 0)
+		return -ENOTSUPP;
+
+	ret = of_graph_parse_endpoint(endpoint, &of_ep);
+	if (ret < 0)
+		return ret;
+
+	if (of_ep.port == connector->hdmi_codec.sound_dai_port)
+		return 0;
+
+	return -EINVAL;
+}
+
+static int drm_connector_hdmi_codec_get_eld(struct device *dev, void *data,
+					    uint8_t *buf, size_t len)
+{
+	struct drm_connector *connector = data;
+
+	//  FIXME: locking against drm_edid_to_eld ?
+	memcpy(buf, connector->eld, min(sizeof(connector->eld), len));
+
+	return 0;
+}
+
+static int drm_connector_hdmi_codec_hook_plugged_cb(struct device *dev,
+						    void *data,
+						    hdmi_codec_plugged_cb fn,
+						    struct device *codec_dev)
+{
+	struct drm_connector *connector = data;
+
+	mutex_lock(&connector->hdmi_codec.lock);
+
+	connector->hdmi_codec.plugged_cb = fn;
+	connector->hdmi_codec.plugged_cb_dev = codec_dev;
+
+	fn(codec_dev, connector->hdmi_codec.last_state);
+
+	mutex_unlock(&connector->hdmi_codec.lock);
+
+	return 0;
+}
+
+void drm_connector_hdmi_codec_plugged_notify(struct drm_connector *connector,
+					     bool plugged)
+{
+	mutex_lock(&connector->hdmi_codec.lock);
+
+	connector->hdmi_codec.last_state = plugged;
+
+	if (connector->hdmi_codec.plugged_cb &&
+	    connector->hdmi_codec.plugged_cb_dev)
+		connector->hdmi_codec.plugged_cb(connector->hdmi_codec.plugged_cb_dev,
+						 connector->hdmi_codec.last_state);
+
+	mutex_unlock(&connector->hdmi_codec.lock);
+}
+EXPORT_SYMBOL(drm_connector_hdmi_codec_plugged_notify);
+
+static const struct hdmi_codec_ops drm_connector_hdmi_codec_ops = {
+	.audio_startup = drm_connector_hdmi_codec_audio_startup,
+	.prepare = drm_connector_hdmi_codec_prepare,
+	.audio_shutdown = drm_connector_hdmi_codec_audio_shutdown,
+	.mute_stream = drm_connector_hdmi_codec_mute_stream,
+	.get_eld = drm_connector_hdmi_codec_get_eld,
+	.get_dai_id = drm_connector_hdmi_codec_get_dai_id,
+	.hook_plugged_cb = drm_connector_hdmi_codec_hook_plugged_cb,
+};
+
+/**
+ * drm_connector_hdmi_codec_cleanup - Cleanup the HDMI Codec for the connector
+ * @connector: A pointer to the connector to cleanup
+ *
+ * Cleanup the HDMI codec device created for the specified connector.
+ * Can be called even if the codec wasn't allocated.
+ */
+void drm_connector_hdmi_codec_cleanup(struct drm_connector *connector)
+{
+	platform_device_unregister(connector->hdmi_codec.codec_pdev);
+}
+
+/**
+ * drm_connector_hdmi_init - Initialize HDMI Codec device for the DRM connector
+ * @connector: A pointer to the connector to allocate codec for
+ *
+ * Create a HDMI codec device to be used with the specified connector.
+ *
+ * Returns:
+ * Zero on success, error code on failure.
+ */
+int drm_connector_hdmi_codec_init(struct drm_connector *connector)
+{
+	struct hdmi_codec_pdata codec_pdata = {};
+	struct platform_device *pdev;
+
+	if (!connector->hdmi.funcs->codec_funcs->prepare ||
+	    !connector->hdmi.funcs->codec_funcs->audio_shutdown ||
+	    !connector->hdmi_codec.dev)
+		return -EINVAL;
+
+	codec_pdata.ops = &drm_connector_hdmi_codec_ops;
+	codec_pdata.i2s = connector->hdmi_codec.i2s,
+	codec_pdata.spdif = connector->hdmi_codec.spdif,
+	codec_pdata.max_i2s_channels = connector->hdmi_codec.max_i2s_channels,
+	codec_pdata.data = connector;
+
+	pdev = platform_device_register_data(connector->hdmi_codec.dev,
+					     HDMI_CODEC_DRV_NAME,
+					     PLATFORM_DEVID_AUTO,
+					     &codec_pdata, sizeof(codec_pdata));
+	if (IS_ERR(pdev))
+		return PTR_ERR(pdev);
+
+	connector->hdmi_codec.codec_pdev = pdev;
+
+	return 0;
+}
diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal.h
index b2b6a8e49dda46f1cb3b048ef7b28356dd3aaa4e..8ed58e482fac4662b659276e8bc17690e1fdb9b7 100644
--- a/drivers/gpu/drm/drm_internal.h
+++ b/drivers/gpu/drm/drm_internal.h
@@ -280,4 +280,9 @@ void drm_framebuffer_print_info(struct drm_printer *p, unsigned int indent,
 				const struct drm_framebuffer *fb);
 void drm_framebuffer_debugfs_init(struct drm_device *dev);
 
+/* drm_connector_hdmi_codec.c */
+
+int drm_connector_hdmi_codec_init(struct drm_connector *connector);
+void drm_connector_hdmi_codec_cleanup(struct drm_connector *connector);
+
 #endif /* __DRM_INTERNAL_H__ */
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index e3fa43291f449d70f3b92a00985336c4f2237bc6..b89f791cfa2be86ce1c5aa124c0f071d7c8a6489 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -46,6 +46,8 @@ struct drm_property_blob;
 struct drm_printer;
 struct drm_privacy_screen;
 struct edid;
+struct hdmi_codec_daifmt;
+struct hdmi_codec_params;
 struct i2c_adapter;
 
 enum drm_connector_force {
@@ -1141,6 +1143,52 @@ struct drm_connector_state {
 	struct drm_connector_hdmi_state hdmi;
 };
 
+struct drm_connector_hdmi_codec_funcs {
+	/**
+	 * @audio_startup:
+	 *
+	 * Called when ASoC starts an audio stream setup. The
+	 * @hdmi_audio_startup is optional.
+	 *
+	 * Returns:
+	 * 0 on success, a negative error code otherwise
+	 */
+	int (*audio_startup)(struct drm_connector *connector);
+
+	/**
+	 * @prepare:
+	 * Configures HDMI-encoder for audio stream. Can be called
+	 * multiple times for each setup. Mandatory.
+	 *
+	 * Returns:
+	 * 0 on success, a negative error code otherwise
+	 */
+	int (*prepare)(struct drm_connector *connector,
+		       struct hdmi_codec_daifmt *fmt,
+		       struct hdmi_codec_params *hparms);
+	/**
+	 * @audio_shutdown:
+	 *
+	 * Shut down the audio stream. Mandatory.
+	 *
+	 * Returns:
+	 * 0 on success, a negative error code otherwise
+	 */
+	void (*audio_shutdown)(struct drm_connector *connector);
+
+	/**
+	 * @mute_stream:
+	 *
+	 * Mute/unmute HDMI audio stream. The @mute_stream callback is
+	 * optional.
+	 *
+	 * Returns:
+	 * 0 on success, a negative error code otherwise
+	 */
+	int (*mute_stream)(struct drm_connector *connector,
+			   bool enable, int direction);
+};
+
 /**
  * struct drm_connector_hdmi_funcs - drm_hdmi_connector control functions
  */
@@ -1198,6 +1246,14 @@ struct drm_connector_hdmi_funcs {
 	int (*write_infoframe)(struct drm_connector *connector,
 			       enum hdmi_infoframe_type type,
 			       const u8 *buffer, size_t len);
+
+	/**
+	 * @codec_funcs:
+	 *
+	 * Implementation of the HDMI codec functionality to be used by the DRM
+	 * HDMI Codec framework.
+	 */
+	const struct drm_connector_hdmi_codec_funcs *codec_funcs;
 };
 
 /**
@@ -1660,6 +1716,22 @@ struct drm_cmdline_mode {
 	bool tv_mode_specified;
 };
 
+struct drm_connector_hdmi_codec {
+	struct platform_device *codec_pdev;
+	struct device *dev;
+
+	struct mutex lock; /* protects last_state and plugged_cb */
+	void (*plugged_cb)(struct device *dev, bool plugged);
+	struct device *plugged_cb_dev;
+	bool last_state;
+
+	int max_i2s_channels;
+	uint i2s: 1;
+	uint spdif: 1;
+
+	int sound_dai_port;
+};
+
 /*
  * struct drm_connector_hdmi - DRM Connector HDMI-related structure
  */
@@ -2118,6 +2190,11 @@ struct drm_connector {
 	 * @hdmi: HDMI-related variable and properties.
 	 */
 	struct drm_connector_hdmi hdmi;
+
+	/**
+	 * @hdmi_codec: HDMI codec properties and non-DRM state.
+	 */
+	struct drm_connector_hdmi_codec hdmi_codec;
 };
 
 #define obj_to_connector(x) container_of(x, struct drm_connector, base)
@@ -2151,6 +2228,9 @@ void drm_connector_unregister(struct drm_connector *connector);
 int drm_connector_attach_encoder(struct drm_connector *connector,
 				      struct drm_encoder *encoder);
 
+void drm_connector_hdmi_codec_plugged_notify(struct drm_connector *connector,
+					     bool plugged);
+
 void drm_connector_cleanup(struct drm_connector *connector);
 
 static inline unsigned int drm_connector_index(const struct drm_connector *connector)

-- 
2.39.5

[PATCH RFC v2 4/7] drm/bridge: connector: add support for HDMI codec framework

[Dmitry Baryshkov]

Add necessary glue code to be able to use new HDMI codec framework from
the DRM bridge drivers. The drm_bridge implements a limited set of the
hdmi_codec_ops interface, with the functions accepting both
drm_connector and drm_bridge instead of just a generic void pointer.

This framework is integrated with the DRM HDMI Connector framework, but
can also be used for DisplayPort connectors.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/display/drm_bridge_connector.c | 95 +++++++++++++++++++++++++-
 include/drm/drm_bridge.h                       | 23 +++++++
 2 files changed, 116 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/display/drm_bridge_connector.c b/drivers/gpu/drm/display/drm_bridge_connector.c
index 320c297008aaa8b6ef5b1f4c71928849b202e8ac..12ab9f14cc8a8672478ae2804c9a68d766d88ea5 100644
--- a/drivers/gpu/drm/display/drm_bridge_connector.c
+++ b/drivers/gpu/drm/display/drm_bridge_connector.c
@@ -20,6 +20,8 @@
 #include <drm/drm_probe_helper.h>
 #include <drm/display/drm_hdmi_state_helper.h>
 
+#include <sound/hdmi-codec.h>
+
 /**
  * DOC: overview
  *
@@ -354,10 +356,80 @@ static int drm_bridge_connector_write_infoframe(struct drm_connector *connector,
 	return bridge->funcs->hdmi_write_infoframe(bridge, type, buffer, len);
 }
 
+static int drm_bridge_connector_audio_startup(struct drm_connector *connector)
+{
+	struct drm_bridge_connector *bridge_connector =
+		to_drm_bridge_connector(connector);
+	struct drm_bridge *bridge;
+
+	bridge = bridge_connector->bridge_hdmi;
+	if (!bridge)
+		return -EINVAL;
+
+	if (bridge->funcs->hdmi_codec_audio_startup)
+		return bridge->funcs->hdmi_codec_audio_startup(connector, bridge);
+	else
+		return 0;
+}
+
+static int drm_bridge_connector_prepare(struct drm_connector *connector,
+					struct hdmi_codec_daifmt *fmt,
+					struct hdmi_codec_params *hparms)
+{
+	struct drm_bridge_connector *bridge_connector =
+		to_drm_bridge_connector(connector);
+	struct drm_bridge *bridge;
+
+	bridge = bridge_connector->bridge_hdmi;
+	if (!bridge)
+		return -EINVAL;
+
+	return bridge->funcs->hdmi_codec_prepare(connector, bridge, fmt, hparms);
+}
+
+static void drm_bridge_connector_audio_shutdown(struct drm_connector *connector)
+{
+	struct drm_bridge_connector *bridge_connector =
+		to_drm_bridge_connector(connector);
+	struct drm_bridge *bridge;
+
+	bridge = bridge_connector->bridge_hdmi;
+	if (!bridge)
+		return;
+
+	bridge->funcs->hdmi_codec_audio_shutdown(connector, bridge);
+}
+
+static int drm_bridge_connector_mute_stream(struct drm_connector *connector,
+					    bool enable, int direction)
+{
+	struct drm_bridge_connector *bridge_connector =
+		to_drm_bridge_connector(connector);
+	struct drm_bridge *bridge;
+
+	bridge = bridge_connector->bridge_hdmi;
+	if (!bridge)
+		return -EINVAL;
+
+	if (bridge->funcs->hdmi_codec_mute_stream)
+		return bridge->funcs->hdmi_codec_mute_stream(connector, bridge,
+							     enable, direction);
+	else
+		return -ENOTSUPP;
+}
+
+static const struct drm_connector_hdmi_codec_funcs drm_bridge_connector_hdmi_codec_funcs = {
+	.audio_startup = drm_bridge_connector_audio_startup,
+	.prepare = drm_bridge_connector_prepare,
+	.audio_shutdown = drm_bridge_connector_audio_shutdown,
+	.mute_stream = drm_bridge_connector_mute_stream,
+};
+
 static const struct drm_connector_hdmi_funcs drm_bridge_connector_hdmi_funcs = {
 	.tmds_char_rate_valid = drm_bridge_connector_tmds_char_rate_valid,
 	.clear_infoframe = drm_bridge_connector_clear_infoframe,
 	.write_infoframe = drm_bridge_connector_write_infoframe,
+	.codec_funcs = &drm_bridge_connector_hdmi_codec_funcs,
 };
 
 /* -----------------------------------------------------------------------------
@@ -459,7 +531,25 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
 	if (connector_type == DRM_MODE_CONNECTOR_Unknown)
 		return ERR_PTR(-EINVAL);
 
-	if (bridge_connector->bridge_hdmi)
+	if (bridge_connector->bridge_hdmi) {
+		bridge = bridge_connector->bridge_hdmi;
+
+		if (bridge->hdmi_codec_i2s ||
+		    bridge->hdmi_codec_spdif) {
+			if (!bridge->funcs->hdmi_codec_prepare ||
+			    !bridge->funcs->hdmi_codec_audio_shutdown)
+				return ERR_PTR(-EINVAL);
+
+			bridge_connector->bridge_hdmi = bridge;
+
+			connector->hdmi_codec.dev = bridge->hdmi_codec_dev;
+			connector->hdmi_codec.i2s = bridge->hdmi_codec_i2s;
+			connector->hdmi_codec.spdif = bridge->hdmi_codec_spdif;
+			connector->hdmi_codec.max_i2s_channels =
+				bridge->hdmi_codec_max_i2s_channels;
+			connector->hdmi_codec.sound_dai_port = bridge->hdmi_codec_dai_port;
+		}
+
 		ret = drmm_connector_hdmi_init(drm, connector,
 					       bridge_connector->bridge_hdmi->vendor,
 					       bridge_connector->bridge_hdmi->product,
@@ -468,10 +558,11 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
 					       connector_type, ddc,
 					       supported_formats,
 					       max_bpc);
-	else
+	} else {
 		ret = drmm_connector_init(drm, connector,
 					  &drm_bridge_connector_funcs,
 					  connector_type, ddc);
+	}
 	if (ret)
 		return ERR_PTR(ret);
 
diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
index e8d735b7f6a480468c88287e2517b387ceec0f22..0ef9580ef6669f84327bdcb85a24fc83f76541bb 100644
--- a/include/drm/drm_bridge.h
+++ b/include/drm/drm_bridge.h
@@ -41,6 +41,8 @@ struct drm_display_info;
 struct drm_minor;
 struct drm_panel;
 struct edid;
+struct hdmi_codec_daifmt;
+struct hdmi_codec_params;
 struct i2c_adapter;
 
 /**
@@ -676,6 +678,21 @@ struct drm_bridge_funcs {
 				    enum hdmi_infoframe_type type,
 				    const u8 *buffer, size_t len);
 
+	int (*hdmi_codec_audio_startup)(struct drm_connector *connector,
+					struct drm_bridge *bridge);
+
+	int (*hdmi_codec_prepare)(struct drm_connector *connector,
+				  struct drm_bridge *bridge,
+				  struct hdmi_codec_daifmt *fmt,
+				  struct hdmi_codec_params *hparms);
+
+	void (*hdmi_codec_audio_shutdown)(struct drm_connector *connector,
+					  struct drm_bridge *bridge);
+
+	int (*hdmi_codec_mute_stream)(struct drm_connector *connector,
+				      struct drm_bridge *bridge,
+				      bool enable, int direction);
+
 	/**
 	 * @debugfs_init:
 	 *
@@ -859,6 +876,12 @@ struct drm_bridge {
 	 * @DRM_BRIDGE_OP_HDMI is set.
 	 */
 	unsigned int max_bpc;
+
+	struct device *hdmi_codec_dev;
+	int hdmi_codec_max_i2s_channels;
+	unsigned int hdmi_codec_i2s : 1;
+	unsigned int hdmi_codec_spdif : 1;
+	int hdmi_codec_dai_port;
 };
 
 static inline struct drm_bridge *

-- 
2.39.5

[PATCH RFC v2 5/7] drm/bridge: lt9611: switch to using the DRM HDMI codec framework

[Dmitry Baryshkov]

Make the Lontium LT9611 DSI-to-HDMI bridge driver use the DRM HDMI Codec
framework. This enables programming of Audio InfoFrames using the HDMI
Connector interface and also enables support for the missing features,
including the ELD retrieval and better hotplug support.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/bridge/lontium-lt9611.c | 171 +++++++++++++-------------------
 1 file changed, 69 insertions(+), 102 deletions(-)

diff --git a/drivers/gpu/drm/bridge/lontium-lt9611.c b/drivers/gpu/drm/bridge/lontium-lt9611.c
index 4fa0dfc5539a5786278221f7c13b6473ab320a9a..9d8b1c8d533c79bd91ae956aa4cb74f3bab6de78 100644
--- a/drivers/gpu/drm/bridge/lontium-lt9611.c
+++ b/drivers/gpu/drm/bridge/lontium-lt9611.c
@@ -45,7 +45,6 @@ struct lt9611 {
 	struct device_node *dsi1_node;
 	struct mipi_dsi_device *dsi0;
 	struct mipi_dsi_device *dsi1;
-	struct platform_device *audio_pdev;
 
 	bool ac_mode;
 
@@ -866,6 +865,10 @@ static int lt9611_hdmi_clear_infoframe(struct drm_bridge *bridge,
 	unsigned int mask;
 
 	switch (type) {
+	case HDMI_INFOFRAME_TYPE_AUDIO:
+		mask = LT9611_INFOFRAME_AUDIO;
+		break;
+
 	case HDMI_INFOFRAME_TYPE_AVI:
 		mask = LT9611_INFOFRAME_AVI;
 		break;
@@ -899,6 +902,11 @@ static int lt9611_hdmi_write_infoframe(struct drm_bridge *bridge,
 	int i;
 
 	switch (type) {
+	case HDMI_INFOFRAME_TYPE_AUDIO:
+		mask = LT9611_INFOFRAME_AUDIO;
+		addr = 0x84b2;
+		break;
+
 	case HDMI_INFOFRAME_TYPE_AVI:
 		mask = LT9611_INFOFRAME_AVI;
 		addr = 0x8440;
@@ -942,6 +950,55 @@ lt9611_hdmi_tmds_char_rate_valid(const struct drm_bridge *bridge,
 	return MODE_OK;
 }
 
+static int lt9611_hdmi_codec_audio_startup(struct drm_connector *connector,
+					   struct drm_bridge *bridge)
+{
+	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
+
+	regmap_write(lt9611->regmap, 0x82d6, 0x8c);
+	regmap_write(lt9611->regmap, 0x82d7, 0x04);
+
+	regmap_write(lt9611->regmap, 0x8406, 0x08);
+	regmap_write(lt9611->regmap, 0x8407, 0x10);
+
+	regmap_write(lt9611->regmap, 0x8434, 0xd5);
+
+	return 0;
+}
+
+static int lt9611_hdmi_codec_prepare(struct drm_connector *connector,
+				     struct drm_bridge *bridge,
+				     struct hdmi_codec_daifmt *fmt,
+				     struct hdmi_codec_params *hparms)
+{
+	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
+
+	if (hparms->sample_rate == 48000)
+		regmap_write(lt9611->regmap, 0x840f, 0x2b);
+	else if (hparms->sample_rate == 96000)
+		regmap_write(lt9611->regmap, 0x840f, 0xab);
+	else
+		return -EINVAL;
+
+	regmap_write(lt9611->regmap, 0x8435, 0x00);
+	regmap_write(lt9611->regmap, 0x8436, 0x18);
+	regmap_write(lt9611->regmap, 0x8437, 0x00);
+
+	return drm_atomic_helper_connector_hdmi_update_audio_infoframe(connector,
+								       &hparms->cea);
+}
+
+static void lt9611_hdmi_codec_audio_shutdown(struct drm_connector *connector,
+					     struct drm_bridge *bridge)
+{
+	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
+
+	drm_atomic_helper_connector_hdmi_clear_audio_infoframe(connector);
+
+	regmap_write(lt9611->regmap, 0x8406, 0x00);
+	regmap_write(lt9611->regmap, 0x8407, 0x00);
+}
+
 static const struct drm_bridge_funcs lt9611_bridge_funcs = {
 	.attach = lt9611_bridge_attach,
 	.mode_valid = lt9611_bridge_mode_valid,
@@ -962,6 +1019,10 @@ static const struct drm_bridge_funcs lt9611_bridge_funcs = {
 	.hdmi_tmds_char_rate_valid = lt9611_hdmi_tmds_char_rate_valid,
 	.hdmi_write_infoframe = lt9611_hdmi_write_infoframe,
 	.hdmi_clear_infoframe = lt9611_hdmi_clear_infoframe,
+
+	.hdmi_codec_audio_startup = lt9611_hdmi_codec_audio_startup,
+	.hdmi_codec_prepare = lt9611_hdmi_codec_prepare,
+	.hdmi_codec_audio_shutdown = lt9611_hdmi_codec_audio_shutdown,
 };
 
 static int lt9611_parse_dt(struct device *dev,
@@ -1015,102 +1076,6 @@ static int lt9611_read_device_rev(struct lt9611 *lt9611)
 	return ret;
 }
 
-static int lt9611_hdmi_hw_params(struct device *dev, void *data,
-				 struct hdmi_codec_daifmt *fmt,
-				 struct hdmi_codec_params *hparms)
-{
-	struct lt9611 *lt9611 = data;
-
-	if (hparms->sample_rate == 48000)
-		regmap_write(lt9611->regmap, 0x840f, 0x2b);
-	else if (hparms->sample_rate == 96000)
-		regmap_write(lt9611->regmap, 0x840f, 0xab);
-	else
-		return -EINVAL;
-
-	regmap_write(lt9611->regmap, 0x8435, 0x00);
-	regmap_write(lt9611->regmap, 0x8436, 0x18);
-	regmap_write(lt9611->regmap, 0x8437, 0x00);
-
-	return 0;
-}
-
-static int lt9611_audio_startup(struct device *dev, void *data)
-{
-	struct lt9611 *lt9611 = data;
-
-	regmap_write(lt9611->regmap, 0x82d6, 0x8c);
-	regmap_write(lt9611->regmap, 0x82d7, 0x04);
-
-	regmap_write(lt9611->regmap, 0x8406, 0x08);
-	regmap_write(lt9611->regmap, 0x8407, 0x10);
-
-	regmap_write(lt9611->regmap, 0x8434, 0xd5);
-
-	return 0;
-}
-
-static void lt9611_audio_shutdown(struct device *dev, void *data)
-{
-	struct lt9611 *lt9611 = data;
-
-	regmap_write(lt9611->regmap, 0x8406, 0x00);
-	regmap_write(lt9611->regmap, 0x8407, 0x00);
-}
-
-static int lt9611_hdmi_i2s_get_dai_id(struct snd_soc_component *component,
-				      struct device_node *endpoint,
-				      void *data)
-{
-	struct of_endpoint of_ep;
-	int ret;
-
-	ret = of_graph_parse_endpoint(endpoint, &of_ep);
-	if (ret < 0)
-		return ret;
-
-	/*
-	 * HDMI sound should be located as reg = <2>
-	 * Then, it is sound port 0
-	 */
-	if (of_ep.port == 2)
-		return 0;
-
-	return -EINVAL;
-}
-
-static const struct hdmi_codec_ops lt9611_codec_ops = {
-	.hw_params	= lt9611_hdmi_hw_params,
-	.audio_shutdown = lt9611_audio_shutdown,
-	.audio_startup	= lt9611_audio_startup,
-	.get_dai_id	= lt9611_hdmi_i2s_get_dai_id,
-};
-
-static struct hdmi_codec_pdata codec_data = {
-	.ops = &lt9611_codec_ops,
-	.max_i2s_channels = 8,
-	.i2s = 1,
-};
-
-static int lt9611_audio_init(struct device *dev, struct lt9611 *lt9611)
-{
-	codec_data.data = lt9611;
-	lt9611->audio_pdev =
-		platform_device_register_data(dev, HDMI_CODEC_DRV_NAME,
-					      PLATFORM_DEVID_AUTO,
-					      &codec_data, sizeof(codec_data));
-
-	return PTR_ERR_OR_ZERO(lt9611->audio_pdev);
-}
-
-static void lt9611_audio_exit(struct lt9611 *lt9611)
-{
-	if (lt9611->audio_pdev) {
-		platform_device_unregister(lt9611->audio_pdev);
-		lt9611->audio_pdev = NULL;
-	}
-}
-
 static int lt9611_probe(struct i2c_client *client)
 {
 	struct lt9611 *lt9611;
@@ -1174,6 +1139,9 @@ static int lt9611_probe(struct i2c_client *client)
 
 	i2c_set_clientdata(client, lt9611);
 
+	/* Disable Audio InfoFrame, enabled by default */
+	regmap_update_bits(lt9611->regmap, 0x843d, LT9611_INFOFRAME_AUDIO, 0);
+
 	lt9611->bridge.funcs = &lt9611_bridge_funcs;
 	lt9611->bridge.of_node = client->dev.of_node;
 	lt9611->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID |
@@ -1182,6 +1150,10 @@ static int lt9611_probe(struct i2c_client *client)
 	lt9611->bridge.type = DRM_MODE_CONNECTOR_HDMIA;
 	lt9611->bridge.vendor = "Lontium";
 	lt9611->bridge.product = "LT9611";
+	lt9611->bridge.hdmi_codec_max_i2s_channels = 8;
+	lt9611->bridge.hdmi_codec_i2s = 1;
+	lt9611->bridge.hdmi_codec_dev = dev;
+	lt9611->bridge.hdmi_codec_dai_port = 2;
 
 	drm_bridge_add(&lt9611->bridge);
 
@@ -1203,10 +1175,6 @@ static int lt9611_probe(struct i2c_client *client)
 
 	lt9611_enable_hpd_interrupts(lt9611);
 
-	ret = lt9611_audio_init(dev, lt9611);
-	if (ret)
-		goto err_remove_bridge;
-
 	return 0;
 
 err_remove_bridge:
@@ -1227,7 +1195,6 @@ static void lt9611_remove(struct i2c_client *client)
 	struct lt9611 *lt9611 = i2c_get_clientdata(client);
 
 	disable_irq(client->irq);
-	lt9611_audio_exit(lt9611);
 	drm_bridge_remove(&lt9611->bridge);
 
 	regulator_bulk_disable(ARRAY_SIZE(lt9611->supplies), lt9611->supplies);

-- 
2.39.5

[PATCH RFC v2 6/7] drm/display/hdmi: implement connector update functions

[Dmitry Baryshkov]

The HDMI Connectors need to perform a variety of tasks when the HDMI
connector state changes. Such tasks include setting or invalidating CEC
address, notifying HDMI codec driver, updating scrambler data, etc.

Implementing such tasks in a driver-specific callbacks is error prone.
Start implementing the generic helper function (currently handling only
the HDMI Codec framework) to be used by driver utilizing HDMI Connector
framework.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/display/drm_hdmi_state_helper.c | 56 +++++++++++++++++++++++++
 include/drm/display/drm_hdmi_state_helper.h     |  4 ++
 2 files changed, 60 insertions(+)

diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
index feb7a3a759811aed70c679be8704072093e2a79b..dc9d0cc162b2197dcbadda26686a9c5652e74107 100644
--- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c
+++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
@@ -748,3 +748,59 @@ drm_atomic_helper_connector_hdmi_clear_audio_infoframe(struct drm_connector *con
 	return ret;
 }
 EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_clear_audio_infoframe);
+
+/**
+ * __drm_atomic_helper_connector_hdmi_update_edid - Update the HDMI Connector basing on passed EDID
+ * @connector: A pointer to the HDMI connector
+ * @drm_edid: EDID to process
+ *
+ * This function should be called as a part of the .detect() / .detect_ctx()
+ * and .force() callbacks, updating the HDMI-specific connector's data. The
+ * function consumes passed EDID, there is no need to free it afterwards. Most
+ * of the drivers should be able to use
+ * @drm_atomic_helper_connector_hdmi_update() instead.
+ *
+ * Returns:
+ * Zero on success, error code on failure.
+ */
+int
+__drm_atomic_helper_connector_hdmi_update_edid(struct drm_connector *connector,
+					       const struct drm_edid *drm_edid)
+{
+	drm_edid_connector_update(connector, drm_edid);
+	drm_edid_free(drm_edid);
+
+	if (!drm_edid) {
+		drm_connector_hdmi_codec_plugged_notify(connector, false);
+
+		// TODO: also handle CEC and scramber, HDMI sink disconnected.
+
+		return 0;
+	}
+
+	drm_connector_hdmi_codec_plugged_notify(connector, true);
+
+	// TODO: also handle CEC and scramber, HDMI sink is now connected.
+
+	return 0;
+}
+EXPORT_SYMBOL(__drm_atomic_helper_connector_hdmi_update_edid);
+
+/**
+ * drm_atomic_helper_connector_hdmi_update - Update the HDMI Connector after reading the EDID
+ * @connector: A pointer to the HDMI connector
+ *
+ * This function should be called as a part of the .detect() / .detect_ctx()
+ * and .force() callbacks, updating the HDMI-specific connector's data.
+ *
+ * Returns:
+ * Zero on success, error code on failure.
+ */
+int
+drm_atomic_helper_connector_hdmi_update(struct drm_connector *connector)
+{
+	const struct drm_edid *drm_edid = drm_edid_read(connector);
+
+	return __drm_atomic_helper_connector_hdmi_update_edid(connector, drm_edid);
+}
+EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_update);
diff --git a/include/drm/display/drm_hdmi_state_helper.h b/include/drm/display/drm_hdmi_state_helper.h
index 2d45fcfa461985065a5e5ad67eddc0b1c556d526..ea0980aa25cbbfdd36f44201888c139b0ee943da 100644
--- a/include/drm/display/drm_hdmi_state_helper.h
+++ b/include/drm/display/drm_hdmi_state_helper.h
@@ -20,4 +20,8 @@ int drm_atomic_helper_connector_hdmi_clear_audio_infoframe(struct drm_connector
 int drm_atomic_helper_connector_hdmi_update_infoframes(struct drm_connector *connector,
 						       struct drm_atomic_state *state);
 
+int __drm_atomic_helper_connector_hdmi_update_edid(struct drm_connector *connector,
+						   const struct drm_edid *drm_edid);
+int drm_atomic_helper_connector_hdmi_update(struct drm_connector *connector);
+
 #endif // DRM_HDMI_STATE_HELPER_H_

-- 
2.39.5

Re: [PATCH RFC v2 6/7] drm/display/hdmi: implement connector update functions

[Jani Nikula]

On Fri, 01 Nov 2024, Dmitry Baryshkov <dmitry.baryshkov@linaro.org> wrote:
> The HDMI Connectors need to perform a variety of tasks when the HDMI
> connector state changes. Such tasks include setting or invalidating CEC
> address, notifying HDMI codec driver, updating scrambler data, etc.
>
> Implementing such tasks in a driver-specific callbacks is error prone.
> Start implementing the generic helper function (currently handling only
> the HDMI Codec framework) to be used by driver utilizing HDMI Connector
> framework.
>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  drivers/gpu/drm/display/drm_hdmi_state_helper.c | 56 +++++++++++++++++++++++++
>  include/drm/display/drm_hdmi_state_helper.h     |  4 ++
>  2 files changed, 60 insertions(+)
>
> diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> index feb7a3a759811aed70c679be8704072093e2a79b..dc9d0cc162b2197dcbadda26686a9c5652e74107 100644
> --- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> +++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> @@ -748,3 +748,59 @@ drm_atomic_helper_connector_hdmi_clear_audio_infoframe(struct drm_connector *con
>  	return ret;
>  }
>  EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_clear_audio_infoframe);
> +
> +/**
> + * __drm_atomic_helper_connector_hdmi_update_edid - Update the HDMI Connector basing on passed EDID
> + * @connector: A pointer to the HDMI connector
> + * @drm_edid: EDID to process
> + *
> + * This function should be called as a part of the .detect() / .detect_ctx()
> + * and .force() callbacks, updating the HDMI-specific connector's data. The
> + * function consumes passed EDID, there is no need to free it afterwards. Most
> + * of the drivers should be able to use
> + * @drm_atomic_helper_connector_hdmi_update() instead.
> + *
> + * Returns:
> + * Zero on success, error code on failure.
> + */
> +int
> +__drm_atomic_helper_connector_hdmi_update_edid(struct drm_connector *connector,
> +					       const struct drm_edid *drm_edid)
> +{
> +	drm_edid_connector_update(connector, drm_edid);
> +	drm_edid_free(drm_edid);

Not fond of splitting resource management responsibilities
asymmetrically like this.

> +
> +	if (!drm_edid) {
> +		drm_connector_hdmi_codec_plugged_notify(connector, false);

Is it a good idea to tie connection status to EDID presence at the
helper level? Nearly the same, but still orthogonal.

> +
> +		// TODO: also handle CEC and scramber, HDMI sink disconnected.
> +
> +		return 0;
> +	}
> +
> +	drm_connector_hdmi_codec_plugged_notify(connector, true);
> +
> +	// TODO: also handle CEC and scramber, HDMI sink is now connected.
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL(__drm_atomic_helper_connector_hdmi_update_edid);

Feels wrong to export and document double underscored functions to
actually be used.

> +
> +/**
> + * drm_atomic_helper_connector_hdmi_update - Update the HDMI Connector after reading the EDID
> + * @connector: A pointer to the HDMI connector
> + *
> + * This function should be called as a part of the .detect() / .detect_ctx()
> + * and .force() callbacks, updating the HDMI-specific connector's data.
> + *
> + * Returns:
> + * Zero on success, error code on failure.
> + */
> +int
> +drm_atomic_helper_connector_hdmi_update(struct drm_connector *connector)
> +{
> +	const struct drm_edid *drm_edid = drm_edid_read(connector);
> +
> +	return __drm_atomic_helper_connector_hdmi_update_edid(connector, drm_edid);
> +}
> +EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_update);
> diff --git a/include/drm/display/drm_hdmi_state_helper.h b/include/drm/display/drm_hdmi_state_helper.h
> index 2d45fcfa461985065a5e5ad67eddc0b1c556d526..ea0980aa25cbbfdd36f44201888c139b0ee943da 100644
> --- a/include/drm/display/drm_hdmi_state_helper.h
> +++ b/include/drm/display/drm_hdmi_state_helper.h
> @@ -20,4 +20,8 @@ int drm_atomic_helper_connector_hdmi_clear_audio_infoframe(struct drm_connector
>  int drm_atomic_helper_connector_hdmi_update_infoframes(struct drm_connector *connector,
>  						       struct drm_atomic_state *state);
>  
> +int __drm_atomic_helper_connector_hdmi_update_edid(struct drm_connector *connector,
> +						   const struct drm_edid *drm_edid);
> +int drm_atomic_helper_connector_hdmi_update(struct drm_connector *connector);
> +
>  #endif // DRM_HDMI_STATE_HELPER_H_

-- 
Jani Nikula, Intel

Re: [PATCH RFC v2 6/7] drm/display/hdmi: implement connector update functions

[Dmitry Baryshkov]

On Fri, Nov 01, 2024 at 12:59:38PM +0200, Jani Nikula wrote:
> On Fri, 01 Nov 2024, Dmitry Baryshkov <dmitry.baryshkov@linaro.org> wrote:
> > The HDMI Connectors need to perform a variety of tasks when the HDMI
> > connector state changes. Such tasks include setting or invalidating CEC
> > address, notifying HDMI codec driver, updating scrambler data, etc.
> >
> > Implementing such tasks in a driver-specific callbacks is error prone.
> > Start implementing the generic helper function (currently handling only
> > the HDMI Codec framework) to be used by driver utilizing HDMI Connector
> > framework.
> >
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > ---
> >  drivers/gpu/drm/display/drm_hdmi_state_helper.c | 56 +++++++++++++++++++++++++
> >  include/drm/display/drm_hdmi_state_helper.h     |  4 ++
> >  2 files changed, 60 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> > index feb7a3a759811aed70c679be8704072093e2a79b..dc9d0cc162b2197dcbadda26686a9c5652e74107 100644
> > --- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> > +++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> > @@ -748,3 +748,59 @@ drm_atomic_helper_connector_hdmi_clear_audio_infoframe(struct drm_connector *con
> >  	return ret;
> >  }
> >  EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_clear_audio_infoframe);
> > +
> > +/**
> > + * __drm_atomic_helper_connector_hdmi_update_edid - Update the HDMI Connector basing on passed EDID
> > + * @connector: A pointer to the HDMI connector
> > + * @drm_edid: EDID to process
> > + *
> > + * This function should be called as a part of the .detect() / .detect_ctx()
> > + * and .force() callbacks, updating the HDMI-specific connector's data. The
> > + * function consumes passed EDID, there is no need to free it afterwards. Most
> > + * of the drivers should be able to use
> > + * @drm_atomic_helper_connector_hdmi_update() instead.
> > + *
> > + * Returns:
> > + * Zero on success, error code on failure.
> > + */
> > +int
> > +__drm_atomic_helper_connector_hdmi_update_edid(struct drm_connector *connector,
> > +					       const struct drm_edid *drm_edid)
> > +{
> > +	drm_edid_connector_update(connector, drm_edid);
> > +	drm_edid_free(drm_edid);
> 
> Not fond of splitting resource management responsibilities
> asymmetrically like this.

Ack, I can remove drm_edid_free() call.

> 
> > +
> > +	if (!drm_edid) {
> > +		drm_connector_hdmi_codec_plugged_notify(connector, false);
> 
> Is it a good idea to tie connection status to EDID presence at the
> helper level? Nearly the same, but still orthogonal.

Yes. We have been discussing this in v1 review. Basically, CEC, HDMI
codec and some other features should be pinged without any userspace
interaction. This means that get_modes / fill_modes is mostly out of
question. The final agreement was that the .detect is the best place to
handle them (BTW: this matches the i915 driver, see
intel_hdmi_detect()).

> 
> > +
> > +		// TODO: also handle CEC and scramber, HDMI sink disconnected.
> > +
> > +		return 0;
> > +	}
> > +
> > +	drm_connector_hdmi_codec_plugged_notify(connector, true);
> > +
> > +	// TODO: also handle CEC and scramber, HDMI sink is now connected.
> > +
> > +	return 0;
> > +}
> > +EXPORT_SYMBOL(__drm_atomic_helper_connector_hdmi_update_edid);
> 
> Feels wrong to export and document double underscored functions to
> actually be used.

We have enough examples of EXPORT_SYMBOL(__drm_foo) in DRM helpers. But
I can drop double-underscore if that's the issue.

> 
> > +
> > +/**
> > + * drm_atomic_helper_connector_hdmi_update - Update the HDMI Connector after reading the EDID
> > + * @connector: A pointer to the HDMI connector
> > + *
> > + * This function should be called as a part of the .detect() / .detect_ctx()
> > + * and .force() callbacks, updating the HDMI-specific connector's data.
> > + *
> > + * Returns:
> > + * Zero on success, error code on failure.
> > + */
> > +int
> > +drm_atomic_helper_connector_hdmi_update(struct drm_connector *connector)
> > +{
> > +	const struct drm_edid *drm_edid = drm_edid_read(connector);
> > +
> > +	return __drm_atomic_helper_connector_hdmi_update_edid(connector, drm_edid);
> > +}
> > +EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_update);
> > diff --git a/include/drm/display/drm_hdmi_state_helper.h b/include/drm/display/drm_hdmi_state_helper.h
> > index 2d45fcfa461985065a5e5ad67eddc0b1c556d526..ea0980aa25cbbfdd36f44201888c139b0ee943da 100644
> > --- a/include/drm/display/drm_hdmi_state_helper.h
> > +++ b/include/drm/display/drm_hdmi_state_helper.h
> > @@ -20,4 +20,8 @@ int drm_atomic_helper_connector_hdmi_clear_audio_infoframe(struct drm_connector
> >  int drm_atomic_helper_connector_hdmi_update_infoframes(struct drm_connector *connector,
> >  						       struct drm_atomic_state *state);
> >  
> > +int __drm_atomic_helper_connector_hdmi_update_edid(struct drm_connector *connector,
> > +						   const struct drm_edid *drm_edid);
> > +int drm_atomic_helper_connector_hdmi_update(struct drm_connector *connector);
> > +
> >  #endif // DRM_HDMI_STATE_HELPER_H_
> 
> -- 
> Jani Nikula, Intel

-- 
With best wishes
Dmitry

[PATCH RFC v2 7/7] drm/bridge_connector: hook __drm_atomic_helper_connector_hdmi_update_edid()

[Dmitry Baryshkov]

Extend drm_bridge_connector code to read the EDID and use it to update
connector status if the bridge chain implements HDMI bridge. Performing
it from the generic location minimizes individual bridge's code and
enforces standard behaviour from all corresponding drivers.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/display/drm_bridge_connector.c | 65 ++++++++++++++++++++------
 1 file changed, 51 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/display/drm_bridge_connector.c b/drivers/gpu/drm/display/drm_bridge_connector.c
index 12ab9f14cc8a8672478ae2804c9a68d766d88ea5..4069e0f972d5fcabf7e07238583fc9ea89ab113f 100644
--- a/drivers/gpu/drm/display/drm_bridge_connector.c
+++ b/drivers/gpu/drm/display/drm_bridge_connector.c
@@ -17,6 +17,7 @@
 #include <drm/drm_edid.h>
 #include <drm/drm_managed.h>
 #include <drm/drm_modeset_helper_vtables.h>
+#include <drm/drm_print.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/display/drm_hdmi_state_helper.h>
 
@@ -175,17 +176,53 @@ static void drm_bridge_connector_disable_hpd(struct drm_connector *connector)
  * Bridge Connector Functions
  */
 
+static const struct drm_edid *
+drm_bridge_connector_read_edid(struct drm_connector *connector,
+			       enum drm_connector_status status)
+{
+	struct drm_bridge_connector *bridge_connector =
+		to_drm_bridge_connector(connector);
+	const struct drm_edid *drm_edid;
+	struct drm_bridge *bridge;
+
+	bridge = bridge_connector->bridge_edid;
+	if (!bridge)
+		return NULL;
+
+	if (status != connector_status_connected)
+		return NULL;
+
+	drm_edid = drm_bridge_edid_read(bridge, connector);
+	if (!drm_edid_valid(drm_edid)) {
+		drm_edid_free(drm_edid);
+		return NULL;
+	}
+
+	return drm_edid;
+}
+
 static enum drm_connector_status
 drm_bridge_connector_detect(struct drm_connector *connector, bool force)
 {
 	struct drm_bridge_connector *bridge_connector =
 		to_drm_bridge_connector(connector);
 	struct drm_bridge *detect = bridge_connector->bridge_detect;
+	struct drm_bridge *hdmi = bridge_connector->bridge_hdmi;
 	enum drm_connector_status status;
 
 	if (detect) {
 		status = detect->funcs->detect(detect);
 
+		if (hdmi) {
+			const struct drm_edid *drm_edid = drm_bridge_connector_read_edid(connector,
+											 status);
+			int ret;
+
+			ret = __drm_atomic_helper_connector_hdmi_update_edid(connector, drm_edid);
+			if (ret)
+				drm_warn(connector->dev, "updating EDID failed with %d\n", ret);
+		}
+
 		drm_bridge_connector_hpd_notify(connector, status);
 	} else {
 		switch (connector->connector_type) {
@@ -246,29 +283,29 @@ static const struct drm_connector_funcs drm_bridge_connector_funcs = {
 static int drm_bridge_connector_get_modes_edid(struct drm_connector *connector,
 					       struct drm_bridge *bridge)
 {
+	struct drm_bridge_connector *bridge_connector =
+		to_drm_bridge_connector(connector);
+	struct drm_bridge *hdmi = bridge_connector->bridge_hdmi;
 	enum drm_connector_status status;
 	const struct drm_edid *drm_edid;
-	int n;
 
 	status = drm_bridge_connector_detect(connector, false);
 	if (status != connector_status_connected)
-		goto no_edid;
+		return 0;
 
-	drm_edid = drm_bridge_edid_read(bridge, connector);
-	if (!drm_edid_valid(drm_edid)) {
+	/* In HDMI setup the EDID has been read and handled as a part of .detect() */
+	if (!hdmi) {
+		drm_edid = drm_bridge_connector_read_edid(connector, status);
+		if (!drm_edid) {
+			drm_edid_connector_update(connector, NULL);
+			return 0;
+		}
+
+		drm_edid_connector_update(connector, drm_edid);
 		drm_edid_free(drm_edid);
-		goto no_edid;
 	}
 
-	drm_edid_connector_update(connector, drm_edid);
-	n = drm_edid_connector_add_modes(connector);
-
-	drm_edid_free(drm_edid);
-	return n;
-
-no_edid:
-	drm_edid_connector_update(connector, NULL);
-	return 0;
+	return drm_edid_connector_add_modes(connector);
 }
 
 static int drm_bridge_connector_get_modes(struct drm_connector *connector)

-- 
2.39.5