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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Tue, 28 Nov 2023 16:05:54 +0100
Message-ID: <CACRpkdb49rYZoXG5oDLvoDZ90BgpubpC7jRp=7L5qsk=ipPqyg@mail.gmail.com>
Subject: Re: [PATCH 2/2] gpio: use a mutex to protect the list of GPIO devices
To:     Bartosz Golaszewski <brgl@bgdev.pl>
Cc:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Kent Gibson <warthog618@gmail.com>, linux-gpio@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
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On Tue, Nov 28, 2023 at 3:52=E2=80=AFPM Bartosz Golaszewski <brgl@bgdev.pl>=
 wrote:

> We don't need to lock the GPIO device or chip separately - the
> descriptor structs will stay alive as long as there's a live reference
> to the GPIO device. GPIO device will have an SRCU cookie for
> protecting API calls against removal of the chip.
>
> To summarize: one mutex for the GPIO device list, one lock per GPIO
> descriptor and SRCU protection of the GPIO device's chip.
>
> Does it make sense?

Absolutely, standing by to review, it's gonna look awesome!

Linus