Re: [PATCH 1/4] dt-bindings: display: Add bindings for JDI LPM102A188A

[Diogo Ivo <diogo.ivo@tecnico.ulisboa.pt>]

On Tue, Oct 04, 2022 at 01:05:04PM +0200, Krzysztof Kozlowski wrote:
> On 03/10/2022 19:06, Diogo Ivo wrote:
> > On Fri, Sep 30, 2022 at 12:49:31PM +0200, Krzysztof Kozlowski wrote:
> >> Isn't touchscreen a separate (input) device?
> > 
> > Hello, thank you for the feedback.
> > 
> > According to the downstream kernel's log, it seems like the panel and
> > the touchscreen controller are considered to be embedded in the same unit
> > (for example in [1]), 
> 
> Downstream kernel is not a proof of proper description of hardware. If
> downstream says orange is an apple, does it mean orange is really an
> apple? No... Downstream creates a lot of junk, hacks and workarounds.

After some searching (which I should have done sooner, so
apologies) I came across a teardown of the Pixel C ([1], for completeness),
which incorporates this panel. Indeed a separate touch controller was found,
so it seems the downstream kernel threw me off as per your warning.

[1]: https://www.ifixit.com/Teardown/Google+Pixel+C+Teardown/62277 (Step 4)

> > with the touch input being transmitted via HID-over-I2C,
> > and since I did not find any reset gpio handling in that driver I opted to
> > include this reset here, unless there is a better way of going about this.
> 
> Instead it should be in touch screen device.

Noted, I will remove it from the binding in the next version. 

> Where is the DTS of that device?

The relevant part of the DTS can be found here:
https://android.googlesource.com/kernel/tegra/+/refs/heads/android-tegra-dragon-3.18-oreo/arch/arm64/boot/dts/tegra/tegra210-smaug.dtsi

Best regards,
Diogo