Hi Samuel, for comparison, here is my submission for the IMX EPDC bindings: https://lore.kernel.org/linux-devicetree/20220206080016.796556-2-andreas@xxxxxxxxxxxx/ On Wed, 13 Apr 2022 17:19:02 -0500 Samuel Holland <samuel@xxxxxxxxxxxx> wrote: [...] we have sy7636a driver in kernel which should be suitable for powering a EPD and temperature measurement. So I would expect that to be > + io-channels: > + maxItems: 1 > + description: I/O channel for panel temperature measurement > + so how would I reference the hwmon/thermal(-zone) of the sy7636a here? > + panel-supply: > + description: Regulator supplying the panel's logic voltage > + > + power-domains: > + maxItems: 1 > + > + vcom-supply: > + description: Regulator supplying the panel's compensation voltage > + > + vdrive-supply: > + description: Regulator supplying the panel's gate and source drivers > + SY7636a has only one logical regulator in kernel for for the latter two. If we have a separate panel node, than maybe these regulators should go there as they belong to the panel as they are powering the panel and not the EBC. > + port: > + $ref: /schemas/graph.yaml#/properties/port > + description: OF graph port for the attached display panel > + In my approach for the IMX EPDC, (I will send a better commented one soon) I have no separate subnode to avoid messing with additional display parameters. Not sure what is really better here. > +required: > + - compatible > + - reg > + - interrupts > + - clocks > + - clock-names > + - resets > + - reset-names > + - power-domains > + - panel-supply > + - vcom-supply > + - vdrive-supply If things differ how the different phyiscally existing regulators are mapped into logical ones (even the vdrive supply is still a bunch of physical regulators mapped into one logical one), then not everything can be required. Regards, Andreas