drm/bridge: split HDMI Audio from DRM_BRIDGE_OP_HDMI

As pointed out by Laurent, OP bits are supposed to describe operations.
Split DRM_BRIDGE_OP_HDMI_AUDIO from DRM_BRIDGE_OP_HDMI instead of
overloading DRM_BRIDGE_OP_HDMI.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20250314-dp-hdmi-audio-v6-1-dbd228fa73d7@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

1 files changed, 34 insertions, 12 deletions

diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
index df9bbf6fd1fb..a6fa9bdf10a3 100644
--- a/include/drm/drm_bridge.h
+++ b/include/drm/drm_bridge.h
@@ -681,8 +681,10 @@ struct drm_bridge_funcs {
 	/**
 	 * @hdmi_audio_startup:
 	 *
-	 * Called when ASoC starts an audio stream setup. The
-	 * @hdmi_audio_startup() is optional.
+	 * Called when ASoC starts an audio stream setup.
+	 *
+	 * This callback is optional, it can be implemented by bridges that
+	 * set the @DRM_BRIDGE_OP_HDMI_AUDIO flag in their &drm_bridge->ops.
 	 *
 	 * Returns:
 	 * 0 on success, a negative error code otherwise
@@ -693,8 +695,10 @@ struct drm_bridge_funcs {
 	/**
 	 * @hdmi_audio_prepare:
 	 * Configures HDMI-encoder for audio stream. Can be called multiple
-	 * times for each setup. Mandatory if HDMI audio is enabled in the
-	 * bridge's configuration.
+	 * times for each setup.
+	 *
+	 * This callback is optional but it must be implemented by bridges that
+	 * set the @DRM_BRIDGE_OP_HDMI_AUDIO flag in their &drm_bridge->ops.
 	 *
 	 * Returns:
 	 * 0 on success, a negative error code otherwise
@@ -707,8 +711,10 @@ struct drm_bridge_funcs {
 	/**
 	 * @hdmi_audio_shutdown:
 	 *
-	 * Shut down the audio stream. Mandatory if HDMI audio is enabled in
-	 * the bridge's configuration.
+	 * Shut down the audio stream.
+	 *
+	 * This callback is optional but it must be implemented by bridges that
+	 * set the @DRM_BRIDGE_OP_HDMI_AUDIO flag in their &drm_bridge->ops.
 	 *
 	 * Returns:
 	 * 0 on success, a negative error code otherwise
@@ -719,8 +725,10 @@ struct drm_bridge_funcs {
 	/**
 	 * @hdmi_audio_mute_stream:
 	 *
-	 * Mute/unmute HDMI audio stream. The @hdmi_audio_mute_stream callback
-	 * is optional.
+	 * Mute/unmute HDMI audio stream.
+	 *
+	 * This callback is optional, it can be implemented by bridges that
+	 * set the @DRM_BRIDGE_OP_HDMI_AUDIO flag in their &drm_bridge->ops.
 	 *
 	 * Returns:
 	 * 0 on success, a negative error code otherwise
@@ -814,6 +822,17 @@ enum drm_bridge_ops {
 	 * drivers.
 	 */
 	DRM_BRIDGE_OP_HDMI = BIT(4),
+	/**
+	 * @DRM_BRIDGE_OP_HDMI_AUDIO: The bridge provides HDMI audio operations.
+	 * Bridges that set this flag must implement the
+	 * &drm_bridge_funcs->hdmi_audio_prepare and
+	 * &drm_bridge_funcs->hdmi_audio_shutdown callbacks.
+	 *
+	 * Note: currently there can be at most one bridge in a chain that sets
+	 * this bit. This is to simplify corresponding glue code in connector
+	 * drivers.
+	 */
+	DRM_BRIDGE_OP_HDMI_AUDIO = BIT(5),
 };
 
 /**
@@ -926,23 +945,26 @@ struct drm_bridge {
 	unsigned int max_bpc;
 
 	/**
-	 * @hdmi_audio_dev: device to be used as a parent for the HDMI Codec
+	 * @hdmi_audio_dev: device to be used as a parent for the HDMI Codec if
+	 * @DRM_BRIDGE_OP_HDMI_AUDIO is set.
 	 */
 	struct device *hdmi_audio_dev;
 
 	/**
 	 * @hdmi_audio_max_i2s_playback_channels: maximum number of playback
-	 * I2S channels for the HDMI codec
+	 * I2S channels for the bridge that sets @DRM_BRIDGE_OP_HDMI_AUDIO.
 	 */
 	int hdmi_audio_max_i2s_playback_channels;
 
 	/**
-	 * @hdmi_audio_spdif_playback: set if HDMI codec has S/PDIF playback port
+	 * @hdmi_audio_spdif_playback: set if this bridge has S/PDIF playback
+	 * port for @DRM_BRIDGE_OP_HDMI_AUDIO
 	 */
 	unsigned int hdmi_audio_spdif_playback : 1;
 
 	/**
-	 * @hdmi_audio_dai_port: sound DAI port, -1 if it is not enabled
+	 * @hdmi_audio_dai_port: sound DAI port for @DRM_BRIDGE_OP_HDMI_AUDIO,
+	 * -1 if it is not used.
 	 */
 	int hdmi_audio_dai_port;
 };