drm/vc4: hdmi: stop rereading EDID in get_modes()

The vc4_hdmi_connector_detect_ctx() via vc4_hdmi_handle_hotplug()
already reads EDID and propagates it to the drm_connector. Stop
rereading EDID as a part of the .get_modes() callback and just update
the list of modes. This matches the behaviour of the i915 driver.

Acked-by: Maxime Ripard <mripard@kernel.org>
Tested-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241224-drm-bridge-hdmi-connector-v10-9-dc89577cd438@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

Author: lumag

drivers/gpu/drm/vc4/vc4_hdmi.c

@@ -471,31 +471,10 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector,
 
 static int vc4_hdmi_connector_get_modes(struct drm_connector *connector)
 {
-	struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector);
 	struct vc4_dev *vc4 = to_vc4_dev(connector->dev);
-	const struct drm_edid *drm_edid;
 	int ret = 0;
 
-	/*
-	 * NOTE: This function should really take vc4_hdmi->mutex, but doing so
-	 * results in reentrancy issues since cec_s_phys_addr() might call
-	 * .adap_enable, which leads to that funtion being called with our mutex
-	 * held.
-	 *
-	 * Concurrency isn't an issue at the moment since we don't share
-	 * any state with any of the other frameworks so we can ignore
-	 * the lock for now.
-	 */
-
-	drm_edid = drm_edid_read_ddc(connector, vc4_hdmi->ddc);
-	drm_edid_connector_update(connector, drm_edid);
-	cec_s_phys_addr(vc4_hdmi->cec_adap,
-			connector->display_info.source_physical_address, false);
-	if (!drm_edid)
-		return 0;
-
 	ret = drm_edid_connector_add_modes(connector);
-	drm_edid_free(drm_edid);
 
 	if (!vc4->hvs->vc5_hdmi_enable_hdmi_20) {
 		struct drm_device *drm = connector->dev;