drm/rockchip: cdn-dp: Support HDMI codec plug-change callback

Some audio servers like to monitor a jack device (perhaps combined with
EDID, for audio-presence info) to determine DP/HDMI audio presence.
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20220114150129.v2.2.I20d754a1228aa5c51a18c8eb15a2c60dec25b639@changeidSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/gpu/drm/rockchip/cdn-dp-core.c

@@ -586,6 +586,13 @@ static bool cdn_dp_check_link_status(struct cdn_dp_device *dp)
 	return drm_dp_channel_eq_ok(link_status, min(port->lanes, sink_lanes));
 }
 
+static void cdn_dp_audio_handle_plugged_change(struct cdn_dp_device *dp,
+					       bool plugged)
+{
+	if (dp->codec_dev)
+		dp->plugged_cb(dp->codec_dev, plugged);
+}
+
 static void cdn_dp_encoder_enable(struct drm_encoder *encoder)
 {
 	struct cdn_dp_device *dp = encoder_to_dp(encoder);
@@ -641,6 +648,9 @@ static void cdn_dp_encoder_enable(struct drm_encoder *encoder)
 		DRM_DEV_ERROR(dp->dev, "Failed to valid video %d\n", ret);
 		goto out;
 	}
+
+	cdn_dp_audio_handle_plugged_change(dp, true);
+
 out:
 	mutex_unlock(&dp->lock);
 }
@@ -651,6 +661,8 @@ static void cdn_dp_encoder_disable(struct drm_encoder *encoder)
 	int ret;
 
 	mutex_lock(&dp->lock);
+	cdn_dp_audio_handle_plugged_change(dp, false);
+
 	if (dp->active) {
 		ret = cdn_dp_disable(dp);
 		if (ret) {
@@ -846,11 +858,27 @@ static int cdn_dp_audio_get_eld(struct device *dev, void *data,
 	return 0;
 }
 
+static int cdn_dp_audio_hook_plugged_cb(struct device *dev, void *data,
+					hdmi_codec_plugged_cb fn,
+					struct device *codec_dev)
+{
+	struct cdn_dp_device *dp = dev_get_drvdata(dev);
+
+	mutex_lock(&dp->lock);
+	dp->plugged_cb = fn;
+	dp->codec_dev = codec_dev;
+	cdn_dp_audio_handle_plugged_change(dp, dp->connected);
+	mutex_unlock(&dp->lock);
+
+	return 0;
+}
+
 static const struct hdmi_codec_ops audio_codec_ops = {
 	.hw_params = cdn_dp_audio_hw_params,
 	.audio_shutdown = cdn_dp_audio_shutdown,
 	.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,
 };
 

drivers/gpu/drm/rockchip/cdn-dp-core.h

@@ -10,6 +10,7 @@
 #include <drm/drm_dp_helper.h>
 #include <drm/drm_panel.h>
 #include <drm/drm_probe_helper.h>
+#include <sound/hdmi-codec.h>
 
 #include "rockchip_drm_drv.h"
 
@@ -101,5 +102,8 @@ struct cdn_dp_device {
 
 	u8 dpcd[DP_RECEIVER_CAP_SIZE];
 	bool sink_has_audio;
+
+	hdmi_codec_plugged_cb plugged_cb;
+	struct device *codec_dev;
 };
 #endif  /* _CDN_DP_CORE_H */