Re: [PATCH v5 2/9] arm64: dts: qcom: sc7280: Add support for eDP panel on CRD

[Doug Anderson <dianders@chromium.org>]

Hi,

On Wed, Mar 16, 2022 at 10:36 AM Sankeerth Billakanti
<quic_sbillaka@quicinc.com> wrote:
>
> Enable support for eDP interface via aux_bus on CRD platform.
>
> Signed-off-by: Sankeerth Billakanti <quic_sbillaka@quicinc.com>
> ---
>
> Changes in v5:
>   - Change the order of patches
>   - Remove the backlight nodes
>   - Remove the bias setting
>   - Fix compilation issue
>   - Model VREG_EDP_BP for backlight power
>
> Changes in v4:
>   - Create new patch for name changes
>   - Remove output-low
>
> Changes in v3:
>   - Sort the nodes alphabetically
>   - Use - instead of _ as node names
>   - Place the backlight and panel nodes under root
>   - Change the name of edp_out to mdss_edp_out
>   - Change the names of regulator nodes
>   - Delete unused properties in the board file
>
>
> Changes in v2:
>   - Sort node references alphabetically
>   - Improve readability
>   - Move the pwm pinctrl to pwm node
>   - Move the regulators to root
>   - Define backlight power
>   - Remove dummy regulator node
>   - Cleanup pinctrl definitions
>
>  arch/arm64/boot/dts/qcom/sc7280-crd.dts | 93 +++++++++++++++++++++++++++++++++
>  1 file changed, 93 insertions(+)

At a high level, I'd expect your patch to be based upon Matthias's
series, AKA the 4 patches from:

https://lore.kernel.org/r/20220316172814.v1.1.I2deda8f2cd6adfbb525a97d8fee008a8477b7b0e@changeid/

I'll leave it up to you about whether you care to support eDP on the
old CRD1/2 or just on CRD3. Personally I'd think CRD3 would be enough.

Then, I'd expect your patch to mostly incorporate
<https://crrev.com/c/3379844>, though that patch was written before
aux-bus support so the panel would need to go in a different place.

Stephen already gave some comments and basing on Matthias's patches
will be a pretty big change, so I probably won't comment lots more.


> +&mdss_edp {
> +       status = "okay";
> +
> +       data-lanes = <0 1 2 3>;
> +       vdda-1p2-supply = <&vreg_l6b_1p2>;
> +       vdda-0p9-supply = <&vreg_l10c_0p8>;
> +
> +       aux-bus {
> +               edp_panel: edp-panel {

As Stephen pointed out, it should be called "panel".