xref: /openbmc/linux/include/linux/gpio.h (revision b9544fb5)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * <linux/gpio.h>
4  *
5  * This is the LEGACY GPIO bulk include file, including legacy APIs. It is
6  * used for GPIO drivers still referencing the global GPIO numberspace,
7  * and should not be included in new code.
8  *
9  * If you're implementing a GPIO driver, only include <linux/gpio/driver.h>
10  * If you're implementing a GPIO consumer, only include <linux/gpio/consumer.h>
11  */
12 #ifndef __LINUX_GPIO_H
13 #define __LINUX_GPIO_H
14 
15 #include <linux/errno.h>
16 
17 /* see Documentation/driver-api/gpio/legacy.rst */
18 
19 /* make these flag values available regardless of GPIO kconfig options */
20 #define GPIOF_DIR_OUT	(0 << 0)
21 #define GPIOF_DIR_IN	(1 << 0)
22 
23 #define GPIOF_INIT_LOW	(0 << 1)
24 #define GPIOF_INIT_HIGH	(1 << 1)
25 
26 #define GPIOF_IN		(GPIOF_DIR_IN)
27 #define GPIOF_OUT_INIT_LOW	(GPIOF_DIR_OUT | GPIOF_INIT_LOW)
28 #define GPIOF_OUT_INIT_HIGH	(GPIOF_DIR_OUT | GPIOF_INIT_HIGH)
29 
30 /* Gpio pin is active-low */
31 #define GPIOF_ACTIVE_LOW        (1 << 2)
32 
33 /* Gpio pin is open drain */
34 #define GPIOF_OPEN_DRAIN	(1 << 3)
35 
36 /* Gpio pin is open source */
37 #define GPIOF_OPEN_SOURCE	(1 << 4)
38 
39 #define GPIOF_EXPORT		(1 << 5)
40 #define GPIOF_EXPORT_CHANGEABLE	(1 << 6)
41 #define GPIOF_EXPORT_DIR_FIXED	(GPIOF_EXPORT)
42 #define GPIOF_EXPORT_DIR_CHANGEABLE (GPIOF_EXPORT | GPIOF_EXPORT_CHANGEABLE)
43 
44 /**
45  * struct gpio - a structure describing a GPIO with configuration
46  * @gpio:	the GPIO number
47  * @flags:	GPIO configuration as specified by GPIOF_*
48  * @label:	a literal description string of this GPIO
49  */
50 struct gpio {
51 	unsigned	gpio;
52 	unsigned long	flags;
53 	const char	*label;
54 };
55 
56 #ifdef CONFIG_GPIOLIB
57 
58 #ifdef CONFIG_ARCH_HAVE_CUSTOM_GPIO_H
59 #include <asm/gpio.h>
60 #else
61 
62 #include <asm-generic/gpio.h>
63 
64 static inline int gpio_get_value(unsigned int gpio)
65 {
66 	return __gpio_get_value(gpio);
67 }
68 
69 static inline void gpio_set_value(unsigned int gpio, int value)
70 {
71 	__gpio_set_value(gpio, value);
72 }
73 
74 static inline int gpio_cansleep(unsigned int gpio)
75 {
76 	return __gpio_cansleep(gpio);
77 }
78 
79 static inline int gpio_to_irq(unsigned int gpio)
80 {
81 	return __gpio_to_irq(gpio);
82 }
83 
84 static inline int irq_to_gpio(unsigned int irq)
85 {
86 	return -EINVAL;
87 }
88 
89 #endif /* ! CONFIG_ARCH_HAVE_CUSTOM_GPIO_H */
90 
91 /* CONFIG_GPIOLIB: bindings for managed devices that want to request gpios */
92 
93 struct device;
94 
95 int devm_gpio_request(struct device *dev, unsigned gpio, const char *label);
96 int devm_gpio_request_one(struct device *dev, unsigned gpio,
97 			  unsigned long flags, const char *label);
98 
99 #else /* ! CONFIG_GPIOLIB */
100 
101 #include <linux/bug.h>
102 #include <linux/kernel.h>
103 #include <linux/types.h>
104 
105 struct device;
106 struct gpio_chip;
107 
108 static inline bool gpio_is_valid(int number)
109 {
110 	return false;
111 }
112 
113 static inline int gpio_request(unsigned gpio, const char *label)
114 {
115 	return -ENOSYS;
116 }
117 
118 static inline int gpio_request_one(unsigned gpio,
119 					unsigned long flags, const char *label)
120 {
121 	return -ENOSYS;
122 }
123 
124 static inline int gpio_request_array(const struct gpio *array, size_t num)
125 {
126 	return -ENOSYS;
127 }
128 
129 static inline void gpio_free(unsigned gpio)
130 {
131 	might_sleep();
132 
133 	/* GPIO can never have been requested */
134 	WARN_ON(1);
135 }
136 
137 static inline void gpio_free_array(const struct gpio *array, size_t num)
138 {
139 	might_sleep();
140 
141 	/* GPIO can never have been requested */
142 	WARN_ON(1);
143 }
144 
145 static inline int gpio_direction_input(unsigned gpio)
146 {
147 	return -ENOSYS;
148 }
149 
150 static inline int gpio_direction_output(unsigned gpio, int value)
151 {
152 	return -ENOSYS;
153 }
154 
155 static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
156 {
157 	return -ENOSYS;
158 }
159 
160 static inline int gpio_get_value(unsigned gpio)
161 {
162 	/* GPIO can never have been requested or set as {in,out}put */
163 	WARN_ON(1);
164 	return 0;
165 }
166 
167 static inline void gpio_set_value(unsigned gpio, int value)
168 {
169 	/* GPIO can never have been requested or set as output */
170 	WARN_ON(1);
171 }
172 
173 static inline int gpio_cansleep(unsigned gpio)
174 {
175 	/* GPIO can never have been requested or set as {in,out}put */
176 	WARN_ON(1);
177 	return 0;
178 }
179 
180 static inline int gpio_get_value_cansleep(unsigned gpio)
181 {
182 	/* GPIO can never have been requested or set as {in,out}put */
183 	WARN_ON(1);
184 	return 0;
185 }
186 
187 static inline void gpio_set_value_cansleep(unsigned gpio, int value)
188 {
189 	/* GPIO can never have been requested or set as output */
190 	WARN_ON(1);
191 }
192 
193 static inline int gpio_export(unsigned gpio, bool direction_may_change)
194 {
195 	/* GPIO can never have been requested or set as {in,out}put */
196 	WARN_ON(1);
197 	return -EINVAL;
198 }
199 
200 static inline int gpio_export_link(struct device *dev, const char *name,
201 				unsigned gpio)
202 {
203 	/* GPIO can never have been exported */
204 	WARN_ON(1);
205 	return -EINVAL;
206 }
207 
208 static inline void gpio_unexport(unsigned gpio)
209 {
210 	/* GPIO can never have been exported */
211 	WARN_ON(1);
212 }
213 
214 static inline int gpio_to_irq(unsigned gpio)
215 {
216 	/* GPIO can never have been requested or set as input */
217 	WARN_ON(1);
218 	return -EINVAL;
219 }
220 
221 static inline int irq_to_gpio(unsigned irq)
222 {
223 	/* irq can never have been returned from gpio_to_irq() */
224 	WARN_ON(1);
225 	return -EINVAL;
226 }
227 
228 static inline int devm_gpio_request(struct device *dev, unsigned gpio,
229 				    const char *label)
230 {
231 	WARN_ON(1);
232 	return -EINVAL;
233 }
234 
235 static inline int devm_gpio_request_one(struct device *dev, unsigned gpio,
236 					unsigned long flags, const char *label)
237 {
238 	WARN_ON(1);
239 	return -EINVAL;
240 }
241 
242 #endif /* ! CONFIG_GPIOLIB */
243 
244 #endif /* __LINUX_GPIO_H */
245