From: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Date: Sat, 17 May 2025 01:59:44 +0000 (+0300)
Subject: drm/display: bridge-connector: hook in CEC notifier support
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=65a2575a68e4ff03ba887b5aef679fc95405fcd2;p=thirdparty%2Flinux.git

drm/display: bridge-connector: hook in CEC notifier support

Allow HDMI DRM bridges to create CEC notifier. Physical address is
handled automatically by drm_atomic_helper_connector_hdmi_hotplug()
being called from .detect() path.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20250517-drm-hdmi-connector-cec-v6-8-35651db6f19b@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---

diff --git a/drivers/gpu/drm/display/drm_bridge_connector.c b/drivers/gpu/drm/display/drm_bridge_connector.c
index 381a0f9d4259b..0377dcd691a87 100644
--- a/drivers/gpu/drm/display/drm_bridge_connector.c
+++ b/drivers/gpu/drm/display/drm_bridge_connector.c
@@ -20,6 +20,7 @@
 #include <drm/drm_print.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/display/drm_hdmi_audio_helper.h>
+#include <drm/display/drm_hdmi_cec_helper.h>
 #include <drm/display/drm_hdmi_helper.h>
 #include <drm/display/drm_hdmi_state_helper.h>
 
@@ -113,6 +114,13 @@ struct drm_bridge_connector {
 	 * &DRM_BRIDGE_OP_DP_AUDIO).
 	 */
 	struct drm_bridge *bridge_dp_audio;
+	/**
+	 * @bridge_hdmi_cec:
+	 *
+	 * The bridge in the chain that implements CEC support, if any (see
+	 * DRM_BRIDGE_OP_HDMI_CEC_NOTIFIER).
+	 */
+	struct drm_bridge *bridge_hdmi_cec;
 };
 
 #define to_drm_bridge_connector(x) \
@@ -662,6 +670,13 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
 			bridge_connector->bridge_dp_audio = bridge;
 		}
 
+		if (bridge->ops & DRM_BRIDGE_OP_HDMI_CEC_NOTIFIER) {
+			if (bridge_connector->bridge_hdmi_cec)
+				return ERR_PTR(-EBUSY);
+
+			bridge_connector->bridge_hdmi_cec = bridge;
+		}
+
 		if (!drm_bridge_get_next_bridge(bridge))
 			connector_type = bridge->type;
 
@@ -724,6 +739,15 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
 			return ERR_PTR(ret);
 	}
 
+	if (bridge_connector->bridge_hdmi_cec &&
+	    bridge_connector->bridge_hdmi_cec->ops & DRM_BRIDGE_OP_HDMI_CEC_NOTIFIER) {
+		ret = drmm_connector_hdmi_cec_notifier_register(connector,
+								NULL,
+								bridge->hdmi_cec_dev);
+		if (ret)
+			return ERR_PTR(ret);
+	}
+
 	drm_connector_helper_add(connector, &drm_bridge_connector_helper_funcs);
 
 	if (bridge_connector->bridge_hpd)
diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
index db0d374d863b0..0e5f6a007d536 100644
--- a/include/drm/drm_bridge.h
+++ b/include/drm/drm_bridge.h
@@ -907,6 +907,11 @@ enum drm_bridge_ops {
 	 * flag.
 	 */
 	DRM_BRIDGE_OP_DP_AUDIO = BIT(6),
+	/**
+	 * @DRM_BRIDGE_OP_HDMI_CEC_NOTIFIER: The bridge requires CEC notifier
+	 * to be present.
+	 */
+	DRM_BRIDGE_OP_HDMI_CEC_NOTIFIER = BIT(7),
 };
 
 /**
@@ -1003,6 +1008,12 @@ struct drm_bridge {
 	 */
 	unsigned int max_bpc;
 
+	/**
+	 * @hdmi_cec_dev: device to be used as a containing device for CEC
+	 * functions.
+	 */
+	struct device *hdmi_cec_dev;
+
 	/**
 	 * @hdmi_audio_dev: device to be used as a parent for the HDMI Codec if
 	 * either of @DRM_BRIDGE_OP_HDMI_AUDIO or @DRM_BRIDGE_OP_DP_AUDIO is set.