Re: [PATCH v4 1/2] dt-bindings: media: i2c: Add ov2735 sensor

[Hardevsinh Palaniya]

> On 17/07/2025 09:28, Hardevsinh Palaniya wrote:
> >  Hi Krzysztof,
> > 
> > > On Wed, Jul 16, 2025 at 07:14:16PM +0530, Hardevsinh Palaniya wrote:
> > > > +        properties:
> > > > +          data-lanes:
> > > > +            items:
> > > > +              - const: 1
> > > > +              - const: 2
> > > > +          link-frequencies: true
> > >
> > > Drop
> > >
> > > I don't understand why this appeared. I don't think anyone asked for it?
> >
> > Laurent suggested validating the link frequency in the Device Tree.
> >
> > Link[1]: https://lore.kernel.org/linux-media/20250710212131.GG22436@xxxxxxxxxxxxxxxxxxxxxxxxxx/
> 
> ... and I do not see here validation "that the link frequencies
> specified in DT match".
> 
> How do you validate that 1111 Hz is not / is a valid link frequency? How
> did you exactly resolve the comment about validating?

In the ov2735_parse_endpoint() function, the driver validates the link frequency
from DT using `v4l2_link_freq_to_bitmap()`. If an unsupported value like 1111 Hz is
provided, it returns an error: 

ret = v4l2_link_freq_to_bitmap(ov2735->dev, bus_cfg.link_frequencies,
                               bus_cfg.nr_of_link_frequencies,
                               link_freq_menu_items,
                               ARRAY_SIZE(link_freq_menu_items),
                               &link_freq_bitmap);
if (ret) {
        ret = dev_err_probe(ov2735->dev,
                            -EINVAL, "only 420MHz frequency is available\n");
        goto error_out;
}

So, validation is already done in the driver.

I understand that `link-frequencies: true` in the schema only declares the property
without restricting values. Would you prefer the schema to explicitly allow only
420MHz like this?

link-frequencies:
  items:
  - const: 420000000

Best Regards,
Hardev