powerpc/mm/4k: don't allocate larger pmd page table for 4k
[linux/fpc-iii.git] / include / asm-generic / gpio.h
blob8ca627dcea11096b992135679571fa44bba0ee32
1 #ifndef _ASM_GENERIC_GPIO_H
2 #define _ASM_GENERIC_GPIO_H
4 #include <linux/kernel.h>
5 #include <linux/types.h>
6 #include <linux/errno.h>
7 #include <linux/of.h>
9 #ifdef CONFIG_GPIOLIB
11 #include <linux/compiler.h>
12 #include <linux/gpio/driver.h>
13 #include <linux/gpio/consumer.h>
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).
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.
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.
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
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.
41 * Invalid GPIO numbers are useful for indicating no-such-GPIO in
42 * platform data and other tables.
45 static inline bool gpio_is_valid(int number)
47 return number >= 0 && number < ARCH_NR_GPIOS;
50 struct device;
51 struct gpio;
52 struct seq_file;
53 struct module;
54 struct device_node;
55 struct gpio_desc;
57 /* caller holds gpio_lock *OR* gpio is marked as requested */
58 static inline struct gpio_chip *gpio_to_chip(unsigned gpio)
60 return gpiod_to_chip(gpio_to_desc(gpio));
63 /* Always use the library code for GPIO management calls,
64 * or when sleeping may be involved.
66 extern int gpio_request(unsigned gpio, const char *label);
67 extern void gpio_free(unsigned gpio);
69 static inline int gpio_direction_input(unsigned gpio)
71 return gpiod_direction_input(gpio_to_desc(gpio));
73 static inline int gpio_direction_output(unsigned gpio, int value)
75 return gpiod_direction_output_raw(gpio_to_desc(gpio), value);
78 static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
80 return gpiod_set_debounce(gpio_to_desc(gpio), debounce);
83 static inline int gpio_get_value_cansleep(unsigned gpio)
85 return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio));
87 static inline void gpio_set_value_cansleep(unsigned gpio, int value)
89 return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value);
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.
97 static inline int __gpio_get_value(unsigned gpio)
99 return gpiod_get_raw_value(gpio_to_desc(gpio));
101 static inline void __gpio_set_value(unsigned gpio, int value)
103 return gpiod_set_raw_value(gpio_to_desc(gpio), value);
106 static inline int __gpio_cansleep(unsigned gpio)
108 return gpiod_cansleep(gpio_to_desc(gpio));
111 static inline int __gpio_to_irq(unsigned gpio)
113 return gpiod_to_irq(gpio_to_desc(gpio));
116 extern int gpio_request_one(unsigned gpio, unsigned long flags, const char *label);
117 extern int gpio_request_array(const struct gpio *array, size_t num);
118 extern void gpio_free_array(const struct gpio *array, size_t num);
121 * A sysfs interface can be exported by individual drivers if they want,
122 * but more typically is configured entirely from userspace.
124 static inline int gpio_export(unsigned gpio, bool direction_may_change)
126 return gpiod_export(gpio_to_desc(gpio), direction_may_change);
129 static inline int gpio_export_link(struct device *dev, const char *name,
130 unsigned gpio)
132 return gpiod_export_link(dev, name, gpio_to_desc(gpio));
135 static inline void gpio_unexport(unsigned gpio)
137 gpiod_unexport(gpio_to_desc(gpio));
140 #else /* !CONFIG_GPIOLIB */
142 static inline bool gpio_is_valid(int number)
144 /* only non-negative numbers are valid */
145 return number >= 0;
148 /* platforms that don't directly support access to GPIOs through I2C, SPI,
149 * or other blocking infrastructure can use these wrappers.
152 static inline int gpio_cansleep(unsigned gpio)
154 return 0;
157 static inline int gpio_get_value_cansleep(unsigned gpio)
159 might_sleep();
160 return __gpio_get_value(gpio);
163 static inline void gpio_set_value_cansleep(unsigned gpio, int value)
165 might_sleep();
166 __gpio_set_value(gpio, value);
169 #endif /* !CONFIG_GPIOLIB */
171 #endif /* _ASM_GENERIC_GPIO_H */