[PATCH V3 05/13] drm: bridge: icn6211: Add DSI lane count DT property parsing

[Marek Vasut]

On 3/8/22 09:03, Jagan Teki wrote:

Hi,

[...]

>> @@ -314,7 +321,9 @@ static const struct drm_bridge_funcs chipone_bridge_funcs = {
>>   static int chipone_parse_dt(struct chipone *icn)
>>   {
>>          struct device *dev = icn->dev;
>> +       struct device_node *endpoint;
>>          struct drm_panel *panel;
>> +       int dsi_lanes;
>>          int ret;
>>
>>          icn->vdd1 = devm_regulator_get_optional(dev, "vdd1");
>> @@ -350,15 +359,42 @@ static int chipone_parse_dt(struct chipone *icn)
>>                  return PTR_ERR(icn->enable_gpio);
>>          }
>>
>> +       endpoint = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
>> +       dsi_lanes = of_property_count_u32_elems(endpoint, "data-lanes");
>> +       icn->host_node = of_graph_get_remote_port_parent(endpoint);
>> +       of_node_put(endpoint);
>> +
>> +       if (!icn->host_node)
>> +               return -ENODEV;
> 
> The non-ports-based OF graph returns a -19 example on the Allwinner
> Display pipeline in R16 [1].
> 
> We need to have a helper to return host_node for non-ports as I have
> done it for drm_of_find_bridge.
> 
> [1] https://patchwork.amarulasolutions.com/patch/1805/

The link points to a patch marked "DO NOT MERGE", maybe that patch is 
missing the DSI host port at 0 OF graph link ? Both port at 0 and port at 1 are 
required, see:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/display/bridge/chipone,icn6211.yaml#n53

What is "non-ports-based OF graph" ?

I don't see drm_of_find_bridge() in linux-next , what is that ?