Re: [PATCH v6 5/5] iio: adc: ad9467: check for backend capabilities

[Chris Mason <clm@meta.com>]

On 2/8/26 2:30 PM, Jonathan Cameron wrote:
> On Thu, 05 Feb 2026 12:24:11 +0000
> Tomas Melin <tomas.melin@vaisala.com> wrote:
> 
>> Add capability checks for operation with backends that do not necessarily
>> support full set of features, but are otherwise compatible with the device.
>> This ensures a fully functional device, but with limited capabilities.
>>
>> Signed-off-by: Tomas Melin <tomas.melin@vaisala.com>
> I've mentioned before that I've started messing around with Chris Mason's
> set of Claude Code prompts and today I was trying out the new stuff mentioned in:
> https://lore.kernel.org/all/b187e0c1-1df8-4529-bfe4-0a1d65221adc@meta.com/ 
> 
> 
> Given this patch set is pretty much ready to merge I asked it to take a look
> and it came up with something that certainly merited me taking a look.
> 
>  Issue: In ad9467_chan_test_mode_write(), the testmode_on path is guarded
>   by IIO_BACKEND_CAP_CALIBRATION but the matching testmode_off path is not.
>   On backends without that capability, entering PN test mode succeeds but
>   exiting fails with -EOPNOTSUPP, leaving the ADC stuck in test mode.
> 
> I may be missing some protection path, but I think it is right and if you
> were to set up the test modes with a backend that doesn't support the
> relevant functionality you would indeed be able to turn them on but never
> off again.
> 
> So this might be the first bug in IIO that the LLM found and human's, including
> me, missed!  
> 
> Thanks Chris! I won't +CC you every time but wanted to acknowledge that your
> hard work taming these tools is very useful to me.

I'm really glad the AI reviews are helpful, please don't hesitate to
reach out with feature requests or buggy reviews.

Also, if you're using the prompts in CI, I try to keep the breaking
changes to a minimum, but I'll be refactoring things over the next few
weeks.  The entry points (kernel/review-core.md and kernel/agent/orc.md)
shouldn't change, but some of the other files might move around.

Please don't be shy if we're adding regressions for you, my goal is to
make these easy to consume.

-chris