alistair23-linux/include/linux/gpio.h
Mark Brown 09d71ff194 gpiolib: Implement devm_gpio_request_one()
Allow drivers to use the modern request and configure idiom together
with devres.

As with plain gpio_request() and gpio_request_one() we can't implement
the old school version in terms of _one() as this would force the
explicit selection of a direction in gpio_request() which could break
systems if we pick the wrong one.  Implementing devm_gpio_request_one()
in terms of devm_gpio_request() would needlessly complicate things or
lead to duplication from the unmanaged version depending on how it's
done.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-05-18 16:48:35 -06:00

237 lines
4.6 KiB
C

#ifndef __LINUX_GPIO_H
#define __LINUX_GPIO_H
#include <linux/errno.h>
/* see Documentation/gpio.txt */
/* make these flag values available regardless of GPIO kconfig options */
#define GPIOF_DIR_OUT (0 << 0)
#define GPIOF_DIR_IN (1 << 0)
#define GPIOF_INIT_LOW (0 << 1)
#define GPIOF_INIT_HIGH (1 << 1)
#define GPIOF_IN (GPIOF_DIR_IN)
#define GPIOF_OUT_INIT_LOW (GPIOF_DIR_OUT | GPIOF_INIT_LOW)
#define GPIOF_OUT_INIT_HIGH (GPIOF_DIR_OUT | GPIOF_INIT_HIGH)
/* Gpio pin is open drain */
#define GPIOF_OPEN_DRAIN (1 << 2)
/* Gpio pin is open source */
#define GPIOF_OPEN_SOURCE (1 << 3)
#define GPIOF_EXPORT (1 << 2)
#define GPIOF_EXPORT_CHANGEABLE (1 << 3)
#define GPIOF_EXPORT_DIR_FIXED (GPIOF_EXPORT)
#define GPIOF_EXPORT_DIR_CHANGEABLE (GPIOF_EXPORT | GPIOF_EXPORT_CHANGEABLE)
/**
* struct gpio - a structure describing a GPIO with configuration
* @gpio: the GPIO number
* @flags: GPIO configuration as specified by GPIOF_*
* @label: a literal description string of this GPIO
*/
struct gpio {
unsigned gpio;
unsigned long flags;
const char *label;
};
#ifdef CONFIG_GENERIC_GPIO
#ifdef CONFIG_ARCH_HAVE_CUSTOM_GPIO_H
#include <asm/gpio.h>
#else
#include <asm-generic/gpio.h>
static inline int gpio_get_value(unsigned int gpio)
{
return __gpio_get_value(gpio);
}
static inline void gpio_set_value(unsigned int gpio, int value)
{
__gpio_set_value(gpio, value);
}
static inline int gpio_cansleep(unsigned int gpio)
{
return __gpio_cansleep(gpio);
}
static inline int gpio_to_irq(unsigned int gpio)
{
return __gpio_to_irq(gpio);
}
static inline int irq_to_gpio(unsigned int irq)
{
return -EINVAL;
}
#endif
#else
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/bug.h>
struct device;
struct gpio_chip;
static inline bool gpio_is_valid(int number)
{
return false;
}
static inline int gpio_request(unsigned gpio, const char *label)
{
return -ENOSYS;
}
static inline int devm_gpio_request(struct device *dev, unsigned gpio,
const char *label)
{
return -ENOSYS;
}
static inline int gpio_request_one(unsigned gpio,
unsigned long flags, const char *label)
{
return -ENOSYS;
}
static inline int devm_gpio_request_one(struct device *dev, unsigned gpio,
unsigned long flags, const char *label)
{
return -ENOSYS;
}
static inline int gpio_request_array(const struct gpio *array, size_t num)
{
return -ENOSYS;
}
static inline void gpio_free(unsigned gpio)
{
might_sleep();
/* GPIO can never have been requested */
WARN_ON(1);
}
static inline void devm_gpio_free(struct device *dev, unsigned gpio)
{
might_sleep();
/* GPIO can never have been requested */
WARN_ON(1);
}
static inline void gpio_free_array(const struct gpio *array, size_t num)
{
might_sleep();
/* GPIO can never have been requested */
WARN_ON(1);
}
static inline int gpio_direction_input(unsigned gpio)
{
return -ENOSYS;
}
static inline int gpio_direction_output(unsigned gpio, int value)
{
return -ENOSYS;
}
static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
{
return -ENOSYS;
}
static inline int gpio_get_value(unsigned gpio)
{
/* GPIO can never have been requested or set as {in,out}put */
WARN_ON(1);
return 0;
}
static inline void gpio_set_value(unsigned gpio, int value)
{
/* GPIO can never have been requested or set as output */
WARN_ON(1);
}
static inline int gpio_cansleep(unsigned gpio)
{
/* GPIO can never have been requested or set as {in,out}put */
WARN_ON(1);
return 0;
}
static inline int gpio_get_value_cansleep(unsigned gpio)
{
/* GPIO can never have been requested or set as {in,out}put */
WARN_ON(1);
return 0;
}
static inline void gpio_set_value_cansleep(unsigned gpio, int value)
{
/* GPIO can never have been requested or set as output */
WARN_ON(1);
}
static inline int gpio_export(unsigned gpio, bool direction_may_change)
{
/* GPIO can never have been requested or set as {in,out}put */
WARN_ON(1);
return -EINVAL;
}
static inline int gpio_export_link(struct device *dev, const char *name,
unsigned gpio)
{
/* GPIO can never have been exported */
WARN_ON(1);
return -EINVAL;
}
static inline int gpio_sysfs_set_active_low(unsigned gpio, int value)
{
/* GPIO can never have been requested */
WARN_ON(1);
return -EINVAL;
}
static inline void gpio_unexport(unsigned gpio)
{
/* GPIO can never have been exported */
WARN_ON(1);
}
static inline int gpio_to_irq(unsigned gpio)
{
/* GPIO can never have been requested or set as input */
WARN_ON(1);
return -EINVAL;
}
static inline int irq_to_gpio(unsigned irq)
{
/* irq can never have been returned from gpio_to_irq() */
WARN_ON(1);
return -EINVAL;
}
#endif
#endif /* __LINUX_GPIO_H */