Re: [PATCH v3 0/3] Convert Microchip's HLCDC Text based DT bindings to JSON schema

From: Dharma.B
Date: Fri Jan 19 2024 - 03:41:29 EST


Hi Sam,
On 19/01/24 1:00 am, Sam Ravnborg wrote:
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> Hi Dharma et al.
>
> On Thu, Jan 18, 2024 at 02:56:09PM +0530, Dharma Balasubiramani wrote:
>> Converted the text bindings to YAML and validated them individually using following commands
>>
>> $ make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/
>> $ make dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/
>>
>> changelogs are available in respective patches.
>>
>> Dharma Balasubiramani (3):
>> dt-bindings: display: convert Atmel's HLCDC to DT schema
>> dt-bindings: atmel,hlcdc: convert pwm bindings to json-schema
>> dt-bindings: mfd: atmel,hlcdc: Convert to DT schema format
>
> I know this is a bit late to ask - sorry in advance.
>
> The binding describes the single IP block as a multi functional device,
> but it is a single IP block that includes the display controller and a
> simple pwm that can be used for contrast or backlight.
yes.
>
> If we ignore the fact that the current drivers for hlcdc uses an mfd
> abstraction, is this then the optimal way to describe the HW?
>
>
> In one of my stale git tree I converted atmel lcdc to DT, and here
Are you referring the "bindings/display/atmel,lcdc.txt"?
> I used:
>
> + "#pwm-cells":
> + description:
> + This PWM chip use the default 3 cells bindings
> + defined in ../../pwm/pwm.yaml.
> + const: 3
> +
> + clocks:
> + maxItems: 2
> +
> + clock-names:
> + maxItems: 2
> + items:
> + - const: lcdc_clk
> + - const: hclk
>
> This proved to be a simple way to describe the HW.
>
> To make the DT binding backward compatible you likely need to add a few
> compatible that otherwise would have been left out - but that should do
> the trick.
again you mean the compatibles from atmel,lcdc binding?
>
> The current atmel hlcdc driver that is split in three is IMO an
> over-engineering, and the driver could benefit merging it all in one.
> And the binding should not prevent this.
could you please confirm if my understanding is correct: you want a
unified display binding that encompasses the properties of the two
subdevices (display controller and pwm), eliminating the need to
reference them in additional bindings?
>
> Sam

--
With Best Regards,
Dharma B.