Re: [PATCH] dt-bindings: clock: ti: Convert interface.txt to json-schema

Andreas Kemnade
2023-11-28T08:32:48Z

On Tue, 28 Nov 2023 09:00:16 +0100
Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> wrote:

> > +required:
> > + - compatible
> > + - clocks
> > + - '#clock-cells'
>
> reg is required. Device cannot take "reg" from parent, DTS does not work
> like this.

Well, apparently they do... and I am just dealing with status quo and not
how it should be.
Look at commit 31fc1c63c2ae4a542e3c7ac572a10a59ece45c24
for the reasoning of not having reg.

well, look at drivers/clk/ti/clk.c
ti_clk_get_reg_addr();

...

if (of_property_read_u32_index(node, "reg", index, &val)) {
if (of_property_read_u32_index(node->parent, "reg",
index, &val)) {
pr_err("%pOFn or parent must have reg[%d]!\n",
node, index);
return -EINVAL;
}
}

We have two usecases here (status quo in dts usage and code):
If these interface clocks are below a ti,clksel then we are describing
multiple bits in the same register and therefore every child of ti,clksel
would have the same reg.
If the interface clock is not below a ti,clksel then we have reg.

Regards,
Andreas