Re: [PATCH v3 RESEND] media: i2c: Add OV05C10 camera sensor driver

[Nirujogi, Pratap]

Hi Mehdi, Sakari,

On 6/24/2025 12:34 PM, Mehdi Djait wrote:
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>
>
> Hi Sakari,
>
> On Tue, Jun 24, 2025 at 11:46:27AM +0000, Sakari Ailus wrote:
>
> [...]
>
> > I'm in favour of the latter but both should be workable.
> >
> > Speaking of return values, devm_clk_get_optional() may also return
> > -EPROBE_DEFER. That needs to be handled.
>
> Ack.
>
> > And further on -EPROBE_DEFER, I think the helper should return
> > -EPROBE_DEFER if the "clock-frequency" property doesn't exist on non-OF
> > nodes. That signals the required software nodes required on Intel Windows
> > definitions/ipu-bridge or AMD systems aren't in place yet so really probing
> > should be deferred. This would allow removing the hacks that return
> > -EPROBE_DEFER in sensor drivers when no graph endpoint is found.
>
> device_property_read_u32() returns the following:
>
>   * Return: number of values if @val was %NULL,
>   *         %0 if the property was found (success),
>   *         %-EINVAL if given arguments are not valid,
>   *         %-ENODATA if the property does not have a value,
>   *         %-EPROTO if the property is not an array of numbers,
>   *         %-EOVERFLOW if the size of the property is not as expected.
>   *         %-ENXIO if no suitable firmware interface is present.
>
>
> Do you mean something like this in the helper:
>
> if (ret == -ENODATA && !of_node)
>          return ERR_PTR(-EPROBE_DEFER);
If I understand correctly, the recommendation is to return -EPROBE_DEFER 
on !of_node systems when the driver fails to read the clock-frequency 
property. Kindly confirm.

if (ret && !of_node)
	return ERR_PTR(-EPROBE_DEFER);

Thanks,
Pratap

> --
> Kind Regards
> Mehdi Djait