diff options
| author |   Bartosz Golaszewski <bartosz.golaszewski@linaro.org> | 2024-01-25 09:35:07 +0100 |
|---|---|---|
| committer | Bartosz Golaszewski <bartosz.golaszewski@linaro.org> | 2024-01-29 11:45:49 +0100 |
| commit | 6933ba529d06afdd3faf5501855e410b46b77160 (patch) | |
| tree | c1cd919e34933f98ede5577a4016af050a658957 /include/linux/gpio | |
| parent | gpio: unexport GPIO irq domain functions only used internally (diff) | |
| download | wireguard-linux-6933ba529d06afdd3faf5501855e410b46b77160.tar.xz wireguard-linux-6933ba529d06afdd3faf5501855e410b46b77160.zip | |
gpio: improve the API contract for setting direction
If a GPIO driver returns a positive integer from one of the direction
setter callbacks, we'll end up propagating it to user-space. Whether we
should sanitize the values returned by callbacks is a different question
but let's first improve the documentation and fortify the contract with
GPIO providers.
Reported-by: José Guilherme de Castro Rodrigues <joseguilhermebh@hotmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Kent Gibson <warthog618@gmail.com>
Diffstat (limited to 'include/linux/gpio')
| -rw-r--r-- | include/linux/gpio/driver.h | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index 363d06c7b637..3a37d058cfcf 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -335,10 +335,12 @@ struct gpio_irq_chip { * (same as GPIO_LINE_DIRECTION_OUT / GPIO_LINE_DIRECTION_IN), * or negative error. It is recommended to always implement this * function, even on input-only or output-only gpio chips. - * @direction_input: configures signal "offset" as input, or returns error - * This can be omitted on input-only or output-only gpio chips. - * @direction_output: configures signal "offset" as output, or returns error - * This can be omitted on input-only or output-only gpio chips. + * @direction_input: configures signal "offset" as input, returns 0 on success + * or a negative error number. This can be omitted on input-only or + * output-only gpio chips. + * @direction_output: configures signal "offset" as output, returns 0 on + * success or a negative error number. This can be omitted on input-only + * or output-only gpio chips. * @get: returns value for signal "offset", 0=low, 1=high, or negative error * @get_multiple: reads values for multiple signals defined by "mask" and * stores them in "bits", returns 0 on success or negative error |