Re: [PATCH RFC 3/3] arm64: dts: qcom: x1e78100-lenovo-thinkpad-t14s: add HDMI nodes

[Neil Armstrong <neil.armstrong@linaro.org>]

On 22/08/2025 13:01, Dmitry Baryshkov wrote:
> On Thu, Aug 21, 2025 at 03:53:28PM +0200, Neil Armstrong wrote:
>> The Thinkpad T14s embeds a transparent 4lanes DP->HDMI transceiver
>> connected to the third QMP Combo PHY 4 lanes.
>>
>> Add all the data routing, disable mode switching and specify the
>> QMP Combo PHY should be in DP-Only mode to route the 4 lanes to
>> the underlying DP phy.
>>
>> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
>> ---
>>   .../dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi    | 44 ++++++++++++++++++++++
>>   1 file changed, 44 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi b/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi
>> index 4cf61c2a34e31233b1adc93332bcabef22de3f86..5b62b8c3123633360f249e3ecdc8ea23f44e8e09 100644
>> --- a/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi
>> +++ b/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi
>> @@ -62,6 +62,20 @@ switch-lid {
>>   		};
>>   	};
>>   
>> +
>> +	hdmi-connector {
>> +		compatible = "hdmi-connector";
>> +		type = "a";
>> +		pinctrl-0 = <&hdmi_hpd_default>;
>> +		pinctrl-names = "default";
> 
> If this is a DP HPD signal, it should be a part of the DP device.
> 
>> +
>> +		port {
>> +			hdmi_con: endpoint {
>> +				remote-endpoint = <&usb_1_ss2_qmpphy_out>;
> 
> Please describe the transparent bridge too. It can be covered by the
> simple-bridge.yaml / simple-bridge.c

Ack, indeed it could take the pinctrl thing.

Neil

> 
> 
>> +			};
>> +		};
>> +	};
>> +
>>   	pmic-glink {
>>   		compatible = "qcom,x1e80100-pmic-glink",
>>   			     "qcom,sm8550-pmic-glink",
>> @@ -1007,6 +1021,14 @@ &mdss_dp1_out {
>>   	link-frequencies = /bits/ 64 <1620000000 2700000000 5400000000 8100000000>;
>>   };
>>   
>> +&mdss_dp2 {
>> +	status = "okay";
>> +};
>> +
>> +&mdss_dp2_out {
>> +	data-lanes = <0 1 2 3>;
>> +};
>> +
>>   &mdss_dp3 {
>>   	/delete-property/ #sound-dai-cells;
>>   
>> @@ -1263,6 +1285,12 @@ &tlmm {
>>   			       <72 2>, /* Secure EC I2C connection (?) */
>>   			       <238 1>; /* UFS Reset */
>>   
>> +	hdmi_hpd_default: hdmi-hpd-default-state {
>> +		pins = "gpio126";
>> +		function = "usb2_dp";
>> +		bias-disable;
>> +	};
>> +
>>   	eusb3_reset_n: eusb3-reset-n-state {
>>   		pins = "gpio6";
>>   		function = "gpio";
>> @@ -1486,6 +1514,22 @@ &usb_1_ss0_qmpphy_out {
>>   	remote-endpoint = <&retimer_ss0_ss_in>;
>>   };
>>   
>> +&usb_1_ss2_qmpphy {
>> +	vdda-phy-supply = <&vreg_l2j_1p2>;
>> +	vdda-pll-supply = <&vreg_l2d_0p9>;
>> +
>> +	qcom,combo-initial-mode = "dp";
>> +
>> +	/delete-property/ mode-switch;
>> +	/delete-property/ orientation-switch;
>> +
>> +	status = "okay";
>> +};
>> +
>> +&usb_1_ss2_qmpphy_out {
>> +	remote-endpoint = <&hdmi_con>;
>> +};
>> +
>>   &usb_1_ss1_hsphy {
>>   	vdd-supply = <&vreg_l3j_0p8>;
>>   	vdda12-supply = <&vreg_l2j_1p2>;
>>
>> -- 
>> 2.34.1
>>
>