Re: [PATCH v3 3/4] drm/lcdif: add DRM_BRIDGE_ATTACH_NO_CONNECTOR flag to drm_bridge_attach

[Marek Vasut <marex@denx.de>]

On 1/2/25 6:58 PM, Dmitry Baryshkov wrote:

[...]

>> @@ -97,13 +100,36 @@ static int lcdif_attach_bridge(struct lcdif_drm_private *lcdif)
>>   			return ret;
>>   		}
>>   
>> -		ret = drm_bridge_attach(encoder, bridge, NULL, 0);
>> +		ret = drm_bridge_attach(encoder, bridge, NULL,
>> +					DRM_BRIDGE_ATTACH_NO_CONNECTOR);
>>   		if (ret) {
>>   			of_node_put(ep);
>>   			return dev_err_probe(dev, ret,
>>   					     "Failed to attach bridge for endpoint%u\n",
>>   					     of_ep.id);
>>   		}
>> +
>> +		nextbridge = drm_bridge_get_next_bridge(bridge);
>> +		nextbridge = drm_bridge_get_next_bridge(nextbridge);
>> +		/* Test if connector node in DT, if not, it was created already */
> 
> By whom? And why?

By the HDMI bridge driver, see 1/4.

> There is no display-connector bridge, but there is a
> normal bridge chain, you have passed DRM_BRIDGE_ATTACH_NO_CONNECTOR, so
> now it's a proper time to create drm_bridge_connector. You have added
> the next_bridge_optional flag, but it should just prevent the dw driver
> from returning the error if there is no next_bridge.
So what exactly should I do here ?

If dw_hdmi_parse_dt() only exits with 0 if there is no connector node in 
DT, I don't get any output on the HDMI. I have to create a connector in 
the HDMI bridge driver instead and not here, right ?