Re: [PATCH v6 00/20] gpio: cdev: add uAPI v2

[Shuah Khan <skhan@linuxfoundation.org>]

On 9/8/20 7:09 PM, Kent Gibson wrote:
> On Tue, Sep 08, 2020 at 10:04:05AM -0600, Shuah Khan wrote:
>> On 9/8/20 9:54 AM, Bartosz Golaszewski wrote:
>>> On Tue, Sep 8, 2020 at 5:24 PM Shuah Khan <skhan@linuxfoundation.org> wrote:
>>>>
>>>> On 9/4/20 7:02 AM, Bartosz Golaszewski wrote:
>>>>> On Fri, Sep 4, 2020 at 2:52 PM Kent Gibson <warthog618@gmail.com> wrote:
>>>>>>
>>>>>> On Thu, Sep 03, 2020 at 04:37:50PM +0800, Kent Gibson wrote:
>>>>>>> On Thu, Sep 03, 2020 at 10:02:04AM +0200, Bartosz Golaszewski wrote:
>>>>>>>> On Mon, Aug 31, 2020 at 5:21 AM Kent Gibson <warthog618@gmail.com> wrote:
>>>>>>>>>
>>>>>> [snip]
>>>>>>>>
>>>>>>>> To me it looks good, just a couple nits here and there and some questions.
>>>>>>>>
>>>>>>>> I think it's worth deciding whether we want to keep the selftests in
>>>>>>>> tools/testing/selftests/gpio/ and then maybe consider porting
>>>>>>>> gpio-mockup-chardev.c to V2 or simply outsource it entirely to
>>>>>>>> libgpiod.
>>>>>>>>
>>>>>>>
>>>>>>> Ooops - I wasn't even aware they existed - though it had crossed my mind
>>>>>>> that the kernel should have some selftests somewhere - I use the libgpiod
>>>>>>> tests, from my libgpiod port, and my own Go based test suite for my testing,
>>>>>>> as well as some smoke tests with the tools/gpio.
>>>>>>>
>>>>>>> The libgpiod tests only cover v1 equivalent functionality, while my Go
>>>>>>> tests cover the complete uAPI, and both v1 and v2.
>>>>>>>
>>>>>>> It would be good for the kernel to at least have some smoke tests to
>>>>>>> confirm basic functionality, even thorough testing is left to a
>>>>>>> userspace library.  So the existing tests should be ported to v2, though
>>>>>>> should also retain the v1 tests if v1 is still compiled in.
>>>>>>>
>>>>>>
>>>>>> I've got a v7 ready to submit that includes a couple of patches for the
>>>>>> gpio-mockup selftests (their primary purpose appears to be testing the
>>>>>> mockup module, rather than the GPIO ABI), but I now notice that the
>>>>>> selftests/gpio section of the tree has a different maintainer:
>>>>>>
>>>>>> scripts/get_maintainer.pl 0021-selftests-gpio-port-to-GPIO-uAPI-v2.patch
>>>>>> Bamvor Jian Zhang <bamv2005@gmail.com> (maintainer:GPIO MOCKUP DRIVER)
>>>>>> Shuah Khan <shuah@kernel.org> (maintainer:KERNEL SELFTEST FRAMEWORK)
>>>>>> linux-gpio@vger.kernel.org (open list:GPIO MOCKUP DRIVER)
>>>>>> linux-kselftest@vger.kernel.org (open list:KERNEL SELFTEST FRAMEWORK)
>>>>>> linux-kernel@vger.kernel.org (open list)
>>>>>
>>>>> Bamvor, Shuah: do you still have interest in maintaining these, or can
>>>>> we update MAINTAINERS?
>>>>>
>>>>
>>>> I maintain kselftests and gpio selftest falls under that. Please send
>>>> selftest patches to me so I can review them.
>>>>
>>>> As for the gpio mock driver and test itself, you will have to wait for
>>>> Bamvor to respond.
>>>>
>>>
>>> Hi Shuah,
>>>
>>> I've been de facto maintaining gpio-mockup for a couple years now.
>>> Bamvor has been quite inactive as far as gpio testing goes. I think
>>> it's fine if you ack the selftests changes.
>>>
>>
>> That is fine. I can do quick review and Ack so you can take them
>> through gpio tree.
>>
>>> In fact: I don't want selftests to block getting V2 uAPI upstream so
>>> if that'll look like it's going to take more time then I'm for merging
>>> V2 without any changes to selftests - in the end we have tests in
>>> user-space already.
>>>
>>
>> Tests and features go through subsystem trees to avoid delays. Please
>> make sure the test doesn't break the default kselftest build/run.
>>
>> In the future it would help if you include all the maintainers on the
>> patch series, so I can review the tests from the framework angle to
>> see if they build/run correctly.
>>
> 
> To clarify, the patches have been submitted to the correct maintainers.
> While this v6, and those before, inadvertently broke the gpio selftests
> by removing code they depend on, there have been no code changes in the
> selftest tree, and so nothing for you to review.  The v7 of this series
> restored the functions that the selftests use so that they again build
> and run - still nothing for you to review.
> 

> While I had patches for the selftests available for v7, I pulled them
> from the patch series as I didn't want to bother you or Bamvor with the
> other patches that you wouldn't be interested in.  Further, the gpio
> selftests are intended to test the gpio-mockup, as evidenced by Bamvor
> being their maintainer and the code itself.  There have been no changes
> to the mockup here, and the existing selftests remain valid without being
> ported to the latest GPIO uAPI.  Porting them to the latest uAPI, and then
> removing the resulting dead code from tools/gpio, is a nice to have that
> can wait and shouldn't block getting the uAPI changes in tree.
> 

Thanks for the clarification.

-- Shuah