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Date:   Sun, 26 Nov 2023 08:14:00 +0800
From:   Kent Gibson <warthog618@gmail.com>
To:     Linus Walleij <linus.walleij@linaro.org>
Cc:     Bartosz Golaszewski <brgl@bgdev.pl>,
        Andy Shevchenko <andy@kernel.org>, linux-gpio@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] gpiolib: Drop cargo-culted comment
Message-ID: <ZWKNyFOU65IHND1k@rigel>
References: <20231125-dropcomment-v1-1-15800415aae0@linaro.org>
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 <CACRpkdZvwePEaRVQLafD8KmiOENgEGFFDBXGPqS5_WLzNi2_yA@mail.gmail.com>
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On Sun, Nov 26, 2023 at 12:05:08AM +0100, Linus Walleij wrote:
> On Sat, Nov 25, 2023 at 3:40 AM Kent Gibson <warthog618@gmail.com> wrote:
> > On Sat, Nov 25, 2023 at 12:25:47AM +0100, Linus Walleij wrote:
>
> > > -/* gpio_lock prevents conflicts during gpio_desc[] table updates.
> > > - * While any GPIO is requested, its gpio_chip is not removable;
> > > - * each GPIO's "requested" flag serves as a lock and refcount.
> > > - */
> >
> > Perhaps provide a comment as to what the gpio_lock DOES cover?
>
> Normally yes, but Bartosz just said he is going to replace this spinlock
> with a mutex so it's better if he adds it then.
>

If that is happening soon then leave it to Bart to change both the
comment and lock.

If not, then we now have an undocumented lock.  If the coverage of the
spinlock and proposed mutex are the same why not describe what the lock
covers now?  Then Bart wont have to update the comment.

Cheers,
Kent.