Re: [PATCH 1/9] arm64: dts: qcom: x1-asus-zenbook-a14: Add missing pinctrl for eDP HPD

[Stephan Gerhold <stephan.gerhold@linaro.org>]

On Sat, Aug 16, 2025 at 01:06:50AM +0300, Dmitry Baryshkov wrote:
> On Thu, Aug 14, 2025 at 03:30:28PM +0200, Stephan Gerhold wrote:
> > At the moment, we indirectly rely on the boot firmware to set up the
> > pinctrl for the eDP HPD line coming from the internal display. If the boot
> > firmware does not configure the display (e.g. because a different display
> > is selected for output in the UEFI settings), then the display fails to
> > come up and there are several errors in the kernel log:
> > 
> >  [drm:dpu_encoder_phys_vid_wait_for_commit_done:544] [dpu error]vblank timeout: 80020041
> >  [drm:dpu_kms_wait_for_commit_done:524] [dpu error]wait for commit done returned -110
> >  [drm:dpu_encoder_frame_done_timeout:2715] [dpu error]enc40 frame done timeout
> >  ...
> > 
> > Fix this by adding the missing pinctrl for gpio119 (func1/edp0_hot and
> > bias-disable according to the ACPI DSDT).
> > 
> > Fixes: 6516961352a1 ("arm64: dts: qcom: Add support for X1-based Asus Zenbook A14")
> > Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
> > ---
> >  arch/arm64/boot/dts/qcom/x1-asus-zenbook-a14.dtsi | 9 +++++++++
> >  1 file changed, 9 insertions(+)
> > 
> > diff --git a/arch/arm64/boot/dts/qcom/x1-asus-zenbook-a14.dtsi b/arch/arm64/boot/dts/qcom/x1-asus-zenbook-a14.dtsi
> > index 16d045cf64c08c02c420787e000f4f45cfc2c6ff..613c675aac296f931293a1ba3d8506c6663bad21 100644
> > --- a/arch/arm64/boot/dts/qcom/x1-asus-zenbook-a14.dtsi
> > +++ b/arch/arm64/boot/dts/qcom/x1-asus-zenbook-a14.dtsi
> > @@ -1001,6 +1001,9 @@ &mdss_dp1_out {
> >  &mdss_dp3 {
> >  	/delete-property/ #sound-dai-cells;
> >  
> > +	pinctrl-0 = <&edp_hpd_default>;
> > +	pinctrl-names = "default";
> > +
> >  	status = "okay";
> >  
> >  	aux-bus {
> > @@ -1236,6 +1239,12 @@ cam_indicator_en: cam-indicator-en-state {
> >  		bias-disable;
> >  	};
> >  
> > +	edp_hpd_default: edp-hpd-default-state {
> > +		pins = "gpio119";
> > +		function = "edp0_hot";
> > +		bias-disable;
> > +	};
> 
> I think this is common enough. Let's maybe push this into the SoC dtsi
> instead of copying it to all devices?
> 

I had it there before, but Johan commented on the patch set from Chris
that he would prefer to keep the potentially board-specific pinctrl out
of the SoC dtsi [1]. So I can either address his feedback or yours. :-)

There isn't really a convention for X1E either - we have a wild mix
where some pinctrl is defined in the SoC dtsi (UART, I2C, SDHCI, ...)
and others is copied for each board (e.g. PCIe).

The reason I chose this approach is that I didn't feel it is guaranteed
that the HPD pin has external pull down. It seems to be the case on most
devices, but in theory a device could maybe rely on the internal pull
down. Might be better to have it explicitly defined, the 5 additional
lines are not that much at the end.

I'm also fine with moving it. Perhaps Bjorn or Konrad could comment if
they would prefer to have the pinctrl template defined in the SoC dtsi?

Thanks,
Stephan

[1]: https://lore.kernel.org/linux-arm-msm/Z_kB3jOH04-zFnym@hovoldconsulting.com/