Re: [RFC PATCH] dt-bindings: display: ti,tfp410.txt: convert to yaml

Tomi Valkeinen
2020-05-06T08:02:32Z

Hi Ricardo,

On 06/05/2020 10:21, Ricardo Cañuelo wrote:
> Hi Tomi, thanks for reviewing the patch.
>
> On mar 28-04-2020 12:49:28, Tomi Valkeinen wrote:
>> I don't quite understand this. We cannot have negative numbers in dts files?
>> Or we can, but dt_binding_check doesn't handle them correctly? Or that int32
>> is not supported in yaml bindings?
>
> AFAICT, you can have negative numbers in dts files (see [1] and [2]) and

This is also my understanding after some googling. And there's even of_property_read_s32() in the
kernel.

> the DT schema certainly supports signed integers, but dt_binding_check
> seems to interpret all cells as unsigned 32bit integers because that's
> what they are, really. In kernel code this is not a problem because you

Well, this is in the nitpick category, and maybe not even relevant, but I don't think that's
correct. They're just bits. Some pieces of SW happen to use u32 containers to store the bits. But
what the bits mean is not related to the container.

> can cast the value back to a signed int before you run your own sanity
> checks on them.

Doesn't all this just point to a bug or missing feature in dt_binding_check? That's not a reason to
change the ABI.

Tomi

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