gpio: remove gpiod_sysfs_set_active_low

Remove gpiod_sysfs_set_active_low (and gpio_sysfs_set_active_low) which
allowed code to change the polarity of a gpio line even after it had
been exported through sysfs.

Drivers should not care, and generally does not know, about gpio-line
polarity which is a hardware feature that needs to be described by
firmware.

It is currently possible to define gpio-line polarity in device-tree and
acpi firmware or using platform data. Userspace can also change the
polarity through sysfs.

Note that drivers using the legacy gpio interface could still use
GPIOF_ACTIVE_LOW to change the polarity before exporting the gpio.

There are no in-kernel users of this interface.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Harry Wei <harryxiyou@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@zh-kernel.org
Cc: linux-arch@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Johan Hovold 2015-05-04 17:10:33 +02:00 committed by Linus Walleij
parent 426577bd88
commit 166a85e442
7 changed files with 2 additions and 89 deletions

View file

@ -449,7 +449,6 @@ static inline int desc_to_gpio(const struct gpio_desc *desc)
int gpiod_export(struct gpio_desc *desc, bool direction_may_change);
int gpiod_export_link(struct device *dev, const char *name,
struct gpio_desc *desc);
int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value);
void gpiod_unexport(struct gpio_desc *desc);
#else /* CONFIG_GPIOLIB && CONFIG_GPIO_SYSFS */
@ -466,11 +465,6 @@ static inline int gpiod_export_link(struct device *dev, const char *name,
return -ENOSYS;
}
static inline int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value)
{
return -ENOSYS;
}
static inline void gpiod_unexport(struct gpio_desc *desc)
{
}