* Re: [PATCH] gpiolib: don't bail out if get_direction() fails in gpiochip_add_data()
2025-02-19 14:43 ` [PATCH] gpiolib: don't bail out if get_direction() fails in gpiochip_add_data() Bartosz Golaszewski
@ 2025-02-20 9:17 ` Marek Szyprowski
2025-02-20 12:49 ` Mark Brown
2025-02-20 13:09 ` Bartosz Golaszewski
2 siblings, 0 replies; 4+ messages in thread
From: Marek Szyprowski @ 2025-02-20 9:17 UTC (permalink / raw)
To: Bartosz Golaszewski, Linus Walleij
Cc: linux-gpio, linux-kernel, Bartosz Golaszewski, Mark Brown
On 19.02.2025 15:43, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>
> Since commit 9d846b1aebbe ("gpiolib: check the return value of
> gpio_chip::get_direction()") we check the return value of the
> get_direction() callback as per its API contract. Some drivers have been
> observed to fail to register now as they may call get_direction() in
> gpiochip_add_data() in contexts where it has always silently failed.
> Until we audit all drivers, replace the bail-out to a kernel log
> warning.
>
> Fixes: 9d846b1aebbe ("gpiolib: check the return value of gpio_chip::get_direction()")
> Reported-by: Mark Brown <broonie@kernel.org>
> Closes: https://lore.kernel.org/all/Z7VFB1nST6lbmBIo@finisterre.sirena.org.uk/
> Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
> Closes: https://lore.kernel.org/all/dfe03f88-407e-4ef1-ad30-42db53bbd4e4@samsung.com/
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
This fixes the issue observed on RPi boards without any changes to
gpio/pinctrl driver.
> ---
> drivers/gpio/gpiolib.c | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index 704452fd94bb..48cf1bb23e24 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -1060,7 +1060,15 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
> if (gc->get_direction && gpiochip_line_is_valid(gc, desc_index)) {
> ret = gc->get_direction(gc, desc_index);
> if (ret < 0)
> - goto err_cleanup_desc_srcu;
> + /*
> + * FIXME: Bail-out here once all GPIO drivers
> + * are updated to not return errors in
> + * situations that can be considered normal
> + * operation.
> + */
> + dev_warn(&gdev->dev,
> + "%s: get_direction failed: %d\n",
> + __func__, ret);
>
> assign_bit(FLAG_IS_OUT, &desc->flags, !ret);
> } else {
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] gpiolib: don't bail out if get_direction() fails in gpiochip_add_data()
2025-02-19 14:43 ` [PATCH] gpiolib: don't bail out if get_direction() fails in gpiochip_add_data() Bartosz Golaszewski
2025-02-20 9:17 ` Marek Szyprowski
@ 2025-02-20 12:49 ` Mark Brown
2025-02-20 13:09 ` Bartosz Golaszewski
2 siblings, 0 replies; 4+ messages in thread
From: Mark Brown @ 2025-02-20 12:49 UTC (permalink / raw)
To: Bartosz Golaszewski
Cc: Linus Walleij, linux-gpio, linux-kernel, Bartosz Golaszewski,
Marek Szyprowski
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On Wed, Feb 19, 2025 at 03:43:56PM +0100, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>
> Since commit 9d846b1aebbe ("gpiolib: check the return value of
> gpio_chip::get_direction()") we check the return value of the
> get_direction() callback as per its API contract. Some drivers have been
> observed to fail to register now as they may call get_direction() in
> gpiochip_add_data() in contexts where it has always silently failed.
> Until we audit all drivers, replace the bail-out to a kernel log
> warning.
For at least one of the affected boards:
Tested-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
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^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] gpiolib: don't bail out if get_direction() fails in gpiochip_add_data()
2025-02-19 14:43 ` [PATCH] gpiolib: don't bail out if get_direction() fails in gpiochip_add_data() Bartosz Golaszewski
2025-02-20 9:17 ` Marek Szyprowski
2025-02-20 12:49 ` Mark Brown
@ 2025-02-20 13:09 ` Bartosz Golaszewski
2 siblings, 0 replies; 4+ messages in thread
From: Bartosz Golaszewski @ 2025-02-20 13:09 UTC (permalink / raw)
To: Linus Walleij, Bartosz Golaszewski
Cc: Bartosz Golaszewski, linux-gpio, linux-kernel, Mark Brown,
Marek Szyprowski
From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
On Wed, 19 Feb 2025 15:43:56 +0100, Bartosz Golaszewski wrote:
> Since commit 9d846b1aebbe ("gpiolib: check the return value of
> gpio_chip::get_direction()") we check the return value of the
> get_direction() callback as per its API contract. Some drivers have been
> observed to fail to register now as they may call get_direction() in
> gpiochip_add_data() in contexts where it has always silently failed.
> Until we audit all drivers, replace the bail-out to a kernel log
> warning.
>
> [...]
Applied, thanks!
[1/1] gpiolib: don't bail out if get_direction() fails in gpiochip_add_data()
commit: 96fa9ec477ff60bed87e1441fd43e003179f3253
Best regards,
--
Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
^ permalink raw reply [flat|nested] 4+ messages in thread