Received-SPF: pass (google.com: domain of linux-kernel+bounces-72588-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Precedence: bulk
MIME-Version: 1.0
References: <20240219172514.203750-1-emil.renner.berthing@canonical.com>
In-Reply-To: <20240219172514.203750-1-emil.renner.berthing@canonical.com>
From: Linus Walleij <linus.walleij@linaro.org>
Date: Tue, 20 Feb 2024 09:41:21 +0100
Message-ID: <CACRpkdaS3oEyQjuHK2LVKKGws8CEdgzhWVGEfjJPY+a0ndt0-w@mail.gmail.com>
Subject: Re: [PATCH v1] gpiolib: Handle no pin_ranges in gpiochip_generic_config()
To: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, 
	Bartosz Golaszewski <brgl@bgdev.pl>, Jisheng Zhang <jszhang@kernel.org>, 
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>, 
	Mika Westerberg <mika.westerberg@linux.intel.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Mon, Feb 19, 2024 at 6:25=E2=80=AFPM Emil Renner Berthing
<emil.renner.berthing@canonical.com> wrote:

> Similar to gpiochip_generic_request() and gpiochip_generic_free() the
> gpiochip_generic_config() function needs to handle the case where there
> are no pinctrl pins mapped to the GPIOs, usually through the gpio-ranges
> device tree property.
>
> Commit f34fd6ee1be8 ("gpio: dwapb: Use generic request, free and
> set_config") set the .set_config callback to gpiochip_generic_config()
> in the dwapb GPIO driver so the GPIO API can set pinctrl configuration
> for the corresponding pins. Most boards using the dwapb driver do not
> set the gpio-ranges device tree property though, and in this case
> gpiochip_generic_config() would return -EPROPE_DEFER rather than the
> previous -ENOTSUPP return value. This in turn makes
> gpio_set_config_with_argument_optional() fail and propagate the error to
> any driver requesting GPIOs.
>
> Fixes: 2956b5d94a76 ("pinctrl / gpio: Introduce .set_config() callback fo=
r GPIO chips")
> Reported-by: Jisheng Zhang <jszhang@kernel.org>
> Closes: https://lore.kernel.org/linux-gpio/ZdC_g3U4l0CJIWzh@xhacker/
> Tested-by: Jisheng Zhang <jszhang@kernel.org>
> Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

> I didn't add your rb since I don't think
>   if (IS_ENABLED(CONFIG_PINCTRL) && list_empty(&gc->gpiodev->pin_ranges))
> will work when the pin_ranges member is only there then when
> CONFIG_PINCTRL is defined and it seemed like your rb was on the
> condition that I used that.

I was wrong about that!

Yours,
Linus Walleij