Re: [PATCH v1 09/17] drm/mediatek: hdmi: add connector flag

From: Guillaume Ranquet
Date: Mon Oct 03 2022 - 11:39:35 EST


On Tue, 20 Sep 2022 12:38, AngeloGioacchino Del Regno
<angelogioacchino.delregno@xxxxxxxxxxxxx> wrote:
>Il 19/09/22 18:56, Guillaume Ranquet ha scritto:
>> Add a flag to indicate support for an external connector
>>
>> Signed-off-by: Guillaume Ranquet <granquet@xxxxxxxxxxxx>
>>
>> diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi_common.c b/drivers/gpu/drm/mediatek/mtk_hdmi_common.c
>> index 86653ebaacfd..30407603d693 100644
>> --- a/drivers/gpu/drm/mediatek/mtk_hdmi_common.c
>> +++ b/drivers/gpu/drm/mediatek/mtk_hdmi_common.c
>> @@ -199,20 +199,22 @@ int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi, struct platform_device *pdev,
>> goto put_device;
>> }
>>
>> - remote = of_graph_get_remote_node(np, 1, 0);
>> - if (!remote) {
>> - ret = -EINVAL;
>> - goto put_device;
>> - }
>> -
>> - if (!of_device_is_compatible(remote, "hdmi-connector")) {
>> - hdmi->next_bridge = of_drm_find_bridge(remote);
>> - if (!hdmi->next_bridge) {
>> - dev_err(dev, "Waiting for external bridge\n");
>> - of_node_put(remote);
>> - ret = -EPROBE_DEFER;
>> + if (hdmi->conf->has_connector) {
>
>If MT8195's DPI uses the internal HDMI->DP converter, I say that the external
>DP has HDMI input and DP output.
>Logically, you can't have a HDMI port that's connected to nothing.
>
>Please, rethink this change.
>
>Regards,
>Angelo

Hi Angelo,
Sorry for the late answer.

I have reworked this for V2, to use an hdmi connector device node to "bind"
both the hdmi and hdmi-ddc driver together as with "legacy" code.
So this patch is dropped in V2 (hopefully ready soon).

Just to make things clear, the hardware path on mt8195 is:
DPI1 -> HDMI Tx -> HDMI Phy
DP Intf1 -> DP Tx -> USB Type C Mux -> DP over USB-C

So there's no HDMI->DP converter involved.

Thx,
Guillaume.