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Date:   Sat, 25 Nov 2023 10:40:38 +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: <ZWFepm7ufLdl115j@rigel>
References: <20231125-dropcomment-v1-1-15800415aae0@linaro.org>
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In-Reply-To: <20231125-dropcomment-v1-1-15800415aae0@linaro.org>
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On Sat, Nov 25, 2023 at 12:25:47AM +0100, Linus Walleij wrote:
> This comment about the gpio_lock is just completely confusing and
> misleading. This refers to a gpio_desc that would in 2008 be used
> to hold the list of gpio_chips, but nowadays gpio_desc refers to
> descriptors of individual GPIO lines and this comment is completely
> unparseable. Delete it.
>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
>  drivers/gpio/gpiolib.c | 4 ----
>  1 file changed, 4 deletions(-)
>
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index 95d2a7b2ea3e..1c47af866bf6 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -86,10 +86,6 @@ static struct bus_type gpio_bus_type = {
>   */
>  #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
>
> -/* 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?

>  DEFINE_SPINLOCK(gpio_lock);
>
>  static DEFINE_MUTEX(gpio_lookup_lock);
>
> ---
> base-commit: b85ea95d086471afb4ad062012a4d73cd328fa86
> change-id: 20231125-dropcomment-89e5b7b4cc3f
>
> Best regards,
> --
> Linus Walleij <linus.walleij@linaro.org>
>