1#ifndef _ASM_GENERIC_GPIO_H
  2#define _ASM_GENERIC_GPIO_H
  3
  4#include <linux/kernel.h>
  5#include <linux/types.h>
  6#include <linux/errno.h>
  7#include <linux/of.h>
  8
  9#ifdef CONFIG_GPIOLIB
 10
 11#include <linux/compiler.h>
 12#include <linux/gpio/driver.h>
 13#include <linux/gpio/consumer.h>
 14
 15/* Platforms may implement their GPIO interface with library code,
 16 * at a small performance cost for non-inlined operations and some
 17 * extra memory (for code and for per-GPIO table entries).
 18 *
 19 * While the GPIO programming interface defines valid GPIO numbers
 20 * to be in the range 0..MAX_INT, this library restricts them to the
 21 * smaller range 0..ARCH_NR_GPIOS-1.
 22 *
 23 * ARCH_NR_GPIOS is somewhat arbitrary; it usually reflects the sum of
 24 * builtin/SoC GPIOs plus a number of GPIOs on expanders; the latter is
 25 * actually an estimate of a board-specific value.
 26 */
 27
 28#ifndef ARCH_NR_GPIOS
 29#if defined(CONFIG_ARCH_NR_GPIO) && CONFIG_ARCH_NR_GPIO > 0
 30#define ARCH_NR_GPIOS CONFIG_ARCH_NR_GPIO
 31#else
 32#define ARCH_NR_GPIOS		512
 33#endif
 34#endif
 35
 36/*
 37 * "valid" GPIO numbers are nonnegative and may be passed to
 38 * setup routines like gpio_request().  only some valid numbers
 39 * can successfully be requested and used.
 40 *
 41 * Invalid GPIO numbers are useful for indicating no-such-GPIO in
 42 * platform data and other tables.
 43 */
 44
 45static inline bool gpio_is_valid(int number)
 46{
 47	return number >= 0 && number < ARCH_NR_GPIOS;
 48}
 49
 50struct device;
 51struct gpio;
 52struct seq_file;
 53struct module;
 54struct device_node;
 55struct gpio_desc;
 56
 57/* caller holds gpio_lock *OR* gpio is marked as requested */
 58static inline struct gpio_chip *gpio_to_chip(unsigned gpio)
 59{
 60	return gpiod_to_chip(gpio_to_desc(gpio));
 61}
 62
 63/* Always use the library code for GPIO management calls,
 64 * or when sleeping may be involved.
 65 */
 66extern int gpio_request(unsigned gpio, const char *label);
 67extern void gpio_free(unsigned gpio);
 68
 69static inline int gpio_direction_input(unsigned gpio)
 70{
 71	return gpiod_direction_input(gpio_to_desc(gpio));
 72}
 73static inline int gpio_direction_output(unsigned gpio, int value)
 74{
 75	return gpiod_direction_output_raw(gpio_to_desc(gpio), value);
 76}
 77
 78static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
 79{
 80	return gpiod_set_debounce(gpio_to_desc(gpio), debounce);
 81}
 82
 83static inline int gpio_get_value_cansleep(unsigned gpio)
 84{
 85	return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio));
 86}
 87static inline void gpio_set_value_cansleep(unsigned gpio, int value)
 88{
 89	return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value);
 90}
 91
 92
 93/* A platform's <asm/gpio.h> code may want to inline the I/O calls when
 94 * the GPIO is constant and refers to some always-present controller,
 95 * giving direct access to chip registers and tight bitbanging loops.
 96 */
 97static inline int __gpio_get_value(unsigned gpio)
 98{
 99	return gpiod_get_raw_value(gpio_to_desc(gpio));
100}
101static inline void __gpio_set_value(unsigned gpio, int value)
102{
103	return gpiod_set_raw_value(gpio_to_desc(gpio), value);
104}
105
106static inline int __gpio_cansleep(unsigned gpio)
107{
108	return gpiod_cansleep(gpio_to_desc(gpio));
109}
110
111static inline int __gpio_to_irq(unsigned gpio)
112{
113	return gpiod_to_irq(gpio_to_desc(gpio));
114}
115
116extern int gpio_request_one(unsigned gpio, unsigned long flags, const char *label);
117extern int gpio_request_array(const struct gpio *array, size_t num);
118extern void gpio_free_array(const struct gpio *array, size_t num);
119
120/*
121 * A sysfs interface can be exported by individual drivers if they want,
122 * but more typically is configured entirely from userspace.
123 */
124static inline int gpio_export(unsigned gpio, bool direction_may_change)
125{
126	return gpiod_export(gpio_to_desc(gpio), direction_may_change);
127}
128
129static inline int gpio_export_link(struct device *dev, const char *name,
130				   unsigned gpio)
131{
132	return gpiod_export_link(dev, name, gpio_to_desc(gpio));
133}
134
135static inline void gpio_unexport(unsigned gpio)
136{
137	gpiod_unexport(gpio_to_desc(gpio));
138}
139
140#else	/* !CONFIG_GPIOLIB */
141
142static inline bool gpio_is_valid(int number)
143{
144	/* only non-negative numbers are valid */
145	return number >= 0;
146}
147
148/* platforms that don't directly support access to GPIOs through I2C, SPI,
149 * or other blocking infrastructure can use these wrappers.
150 */
151
152static inline int gpio_cansleep(unsigned gpio)
153{
154	return 0;
155}
156
157static inline int gpio_get_value_cansleep(unsigned gpio)
158{
159	might_sleep();
160	return __gpio_get_value(gpio);
161}
162
163static inline void gpio_set_value_cansleep(unsigned gpio, int value)
164{
165	might_sleep();
166	__gpio_set_value(gpio, value);
167}
168
169#endif /* !CONFIG_GPIOLIB */
170
171#endif /* _ASM_GENERIC_GPIO_H */