Re: [PATCH] nvmem: core: Mark nWP GPIO as non-exclusive

Bartosz Golaszewski <[email protected]> Mon, 27 Jul 2026 06:10:35 -0700
Newsgroups org.kernel.vger.linux-i2c,org.kernel.vger.linux-kernel
Message-ID <CAMRc=Mfm1R+CNt5nRY=A29TqTxHFZCHzZsWYd-WpE1yGrwt3Vw@mail.gmail.com>
On Fri, 24 Jul 2026 14:51:08 +0200, Marek Vasut <[email protected]> said:
> On 7/24/26 9:30 AM, Bartosz Golaszewski wrote:
>
> Hello Bartosz,
>
>>> I tried to look into the gpio-shared* , but I couldn't figure out how to
>>> describe it in DT. Do you have any examples?
>>>
>>> Take for example this DT snippet:
>>>
>>> gpio: gpio-controller { ... };
>>>
>>> i2c {
>>>     eeprom@0 {
>>>       wp-gpios = <&gpio 0 0>;
>>>       ...
>>>     };
>>>
>>>     eeprom@1 {
>>>       wp-gpios = <&gpio 0 0>;
>>>       ...
>>>     };
>>> };
>>>
>>> I assume there has to be some new glue node between the eeproms and the
>>> GPIO controller somewhere ?
>>>
>>> Thank you for your help !
>>>
>>
>> No, this is literally how you do it. If you enable HAVE_SHARED_GPIOs and
>> DEBUG_GPIO, you should see it being picked up in the kernel log.
> Ah, HAVE_SHARED_GPIOS is what I did not have enabled. Is there any
> reason why this is not enabled by default ?
>

It will be. I'm doing it gradually. It's enabled for Qualcomm platforms by
default and - by extension - in arm64 defconfig. I plan to enable it for other
platforms and architectures too, I just don't want to rush it. Enabling it for
arm64 defconfig had caused quite a lot of regressions a few months ago so I
prefer to be careful.

What platform are you running this on?

Bart