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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_GENERIC_GPIO_H
#define _ASM_GENERIC_GPIO_H
#include <linux/types.h>
#include <linux/errno.h>
#ifdef CONFIG_GPIOLIB
#include <linux/compiler.h>
#include <linux/gpio/driver.h>
#include <linux/gpio/consumer.h>
/* Platforms may implement their GPIO interface with library code,
* at a small performance cost for non-inlined operations and some
* extra memory (for code and for per-GPIO table entries).
*
* While the GPIO programming interface defines valid GPIO numbers
* to be in the range 0..MAX_INT, this library restricts them to the
* smaller range 0..ARCH_NR_GPIOS-1.
*
* ARCH_NR_GPIOS is somewhat arbitrary; it usually reflects the sum of
* builtin/SoC GPIOs plus a number of GPIOs on expanders; the latter is
* actually an estimate of a board-specific value.
*/
#ifndef ARCH_NR_GPIOS
#if defined(CONFIG_ARCH_NR_GPIO) && CONFIG_ARCH_NR_GPIO > 0
#define ARCH_NR_GPIOS CONFIG_ARCH_NR_GPIO
#else
#define ARCH_NR_GPIOS 512
#endif
#endif
/*
* "valid" GPIO numbers are nonnegative and may be passed to
* setup routines like gpio_request(). only some valid numbers
* can successfully be requested and used.
*
* Invalid GPIO numbers are useful for indicating no-such-GPIO in
* platform data and other tables.
*/
static inline bool gpio_is_valid(int number)
{
return number >= 0 && number < ARCH_NR_GPIOS;
}
struct device;
struct gpio;
struct seq_file;
struct module;
struct device_node;
struct gpio_desc;
/* caller holds gpio_lock *OR* gpio is marked as requested */
static inline struct gpio_chip *gpio_to_chip(unsigned gpio)
{
return gpiod_to_chip(gpio_to_desc(gpio));
}
/* Always use the library code for GPIO management calls,
* or when sleeping may be involved.
*/
extern int gpio_request(unsigned gpio, const char *label);
extern void gpio_free(unsigned gpio);
static inline int gpio_direction_input(unsigned gpio)
{
return gpiod_direction_input(gpio_to_desc(gpio));
}
static inline int gpio_direction_output(unsigned gpio, int value)
{
return gpiod_direction_output_raw(gpio_to_desc(gpio), value);
}
static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
{
return gpiod_set_debounce(gpio_to_desc(gpio), debounce);
}
static inline int gpio_get_value_cansleep(unsigned gpio)
{
return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio));
}
static inline void gpio_set_value_cansleep(unsigned gpio, int value)
{
return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value);
}
/* A platform's <asm/gpio.h> code may want to inline the I/O calls when
* the GPIO is constant and refers to some always-present controller,
* giving direct access to chip registers and tight bitbanging loops.
*/
static inline int __gpio_get_value(unsigned gpio)
{
return gpiod_get_raw_value(gpio_to_desc(gpio));
}
static inline void __gpio_set_value(unsigned gpio, int value)
{
return gpiod_set_raw_value(gpio_to_desc(gpio), value);
}
static inline int __gpio_cansleep(unsigned gpio)
{
return gpiod_cansleep(gpio_to_desc(gpio));
}
static inline int __gpio_to_irq(unsigned gpio)
{
return gpiod_to_irq(gpio_to_desc(gpio));
}
extern int gpio_request_one(unsigned gpio, unsigned long flags, const char *label);
extern int gpio_request_array(const struct gpio *array, size_t num);
extern void gpio_free_array(const struct gpio *array, size_t num);
/*
* A sysfs interface can be exported by individual drivers if they want,
* but more typically is configured entirely from userspace.
*/
static inline int gpio_export(unsigned gpio, bool direction_may_change)
{
return gpiod_export(gpio_to_desc(gpio), direction_may_change);
}
static inline int gpio_export_link(struct device *dev, const char *name,
unsigned gpio)
{
return gpiod_export_link(dev, name, gpio_to_desc(gpio));
}
static inline void gpio_unexport(unsigned gpio)
{
gpiod_unexport(gpio_to_desc(gpio));
}
#else /* !CONFIG_GPIOLIB */
#include <linux/kernel.h>
static inline bool gpio_is_valid(int number)
{
/* only non-negative numbers are valid */
return number >= 0;
}
/* platforms that don't directly support access to GPIOs through I2C, SPI,
* or other blocking infrastructure can use these wrappers.
*/
static inline int gpio_cansleep(unsigned gpio)
{
return 0;
}
static inline int gpio_get_value_cansleep(unsigned gpio)
{
might_sleep();
return __gpio_get_value(gpio);
}
static inline void gpio_set_value_cansleep(unsigned gpio, int value)
{
might_sleep();
__gpio_set_value(gpio, value);
}
#endif /* !CONFIG_GPIOLIB */
#endif /* _ASM_GENERIC_GPIO_H */
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