Re: [RFC v3 01/18] dt-bindings: clock: Add VO subsystem clock controller support

Michal Wilczynski
2025-01-21T21:29:54Z

On 1/21/25 10:47, Krzysztof Kozlowski wrote:
> On Mon, Jan 20, 2025 at 06:20:54PM +0100, Michal Wilczynski wrote:
>> properties:
>> compatible:
>> - const: thead,th1520-clk-ap
>> + enum:
>> + - thead,th1520-clk-ap
>> + - thead,th1520-clk-vo
>>
>> reg:
>> maxItems: 1
>>
>> clocks:
>> items:
>> - - description: main oscillator (24MHz)
>> + - description: main oscillator (24MHz) or CLK_VIDEO_PLL
>
> thead,th1520-clk-ap gets also VIDEO_PLL? Aren't both serving the same
> purpose from these devices point of view? Bindings are telling what this
> device is expecting.

Since thead,th1520-clk-ap configures PLL clocks it takes the oscillator
24MHz as an input, so no.

The VO subsystem takes as an input VIDEO_PLL that's configured by the
AP.

I could do something like this if this needs to be formally expressed in
the schema:

if:
properties:
compatible:
contains:
const: thead,th1520-clk-ap
then:
properties:
clocks:
description:
main oscillator (24MHz)

if:
properties:
compatible:
contains:
const: thead,th1520-clk-vo
then:
properties:
clocks:
description:
VIDEO_PLL (derived from AP) for the VO clock controller.

>
>>
>> "#clock-cells":
>> const: 1
>> @@ -51,3 +54,10 @@ examples:
>> clocks = <&osc>;
>> #clock-cells = <1>;
>> };
>> +
>> + clock-controller@ff010000 {
>> + compatible = "thead,th1520-clk-vo";
>
> Difference in one property does not justify new example. If there is
> goign to be resend, just drop.
>
>
>> + reg = <0xff010000 0x1000>;
>> + clocks = <&clk CLK_VIDEO_PLL>;
>> + #clock-cells = <1>;
>
> Best regards,
> Krzysztof