Re: [PATCH v6 2/2] dts: nxp: mxs: Add descriptions for imx287 based btt3-[012] devices

From: Lukasz Majewski
Date: Mon Sep 23 2024 - 05:47:23 EST


Hi Fabio,

> Hi Lukasz,
>
> On Thu, Sep 12, 2024 at 9:48 AM Lukasz Majewski <lukma@xxxxxxx> wrote:
>
> > +&lcdif {
> > + pinctrl-names = "default";
> > + pinctrl-0 = <&lcdif_24bit_pins_a>, <&lcdif_sync_pins_bttc>,
> > + <&lcdif_reset_pins_bttc>;
> > + lcd-supply = <&reg_3v3>;
> > + display = <&display0>;
> > + status = "okay";
> > + display0: display0 {
> > + bits-per-pixel = <32>;
> > + bus-width = <24>;
> > + display-timings {
> > + native-mode = <&timing0>;
> > + timing0: timing0 {
> > + clock-frequency = <6500000>;
> > + hactive = <320>;
> > + vactive = <240>;
> > + hfront-porch = <20>;
> > + hback-porch = <38>;
> > + hsync-len = <30>;
> > + vfront-porch = <4>;
> > + vback-porch = <14>;
> > + vsync-len = <4>;
> > + hsync-active = <0>;
> > + vsync-active = <0>;
> > + de-active = <0>;
> > + pixelclk-active = <1>;
>
> According to fsl,lcdif.yaml, a remote-endpoint to the display is
> needed.
>
> See imx28-evk.dts for an example.

This file has the:
panel {
compatible = "sii,43wvf1g";

Whereas in those devices (i.e. btt3) - I don't know the names of the
displays - manufacturer buys them according to the timing properties.

Hence the question - how shall I proceed?

IMHO the most straightforward way is to modify fsl,lcdif.yaml to
not require "port" and "remote-endpoint" and instead add support for
"display-timings" and "timingX"

Especially that
Documentation/devicetree/bindings/display/panel/display-timings.yaml

are already defined and used by many imx boards (from imx25 to imx6q)
- git grep -n "display-timings"

Even the imx28-m28evk.dts is using the "display-timings" and not
"remote-endpoint" approach.


Best regards,

Lukasz Majewski

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