xref: /openbmc/linux/include/linux/gpio.h (revision 3a83e4e6)
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 void devm_gpio_free(struct device *dev, unsigned int gpio);
99 
100 #else /* ! CONFIG_GPIOLIB */
101 
102 #include <linux/kernel.h>
103 #include <linux/types.h>
104 #include <linux/bug.h>
105 
106 struct device;
107 struct gpio_chip;
108 
109 static inline bool gpio_is_valid(int number)
110 {
111 	return false;
112 }
113 
114 static inline int gpio_request(unsigned gpio, const char *label)
115 {
116 	return -ENOSYS;
117 }
118 
119 static inline int gpio_request_one(unsigned gpio,
120 					unsigned long flags, const char *label)
121 {
122 	return -ENOSYS;
123 }
124 
125 static inline int gpio_request_array(const struct gpio *array, size_t num)
126 {
127 	return -ENOSYS;
128 }
129 
130 static inline void gpio_free(unsigned gpio)
131 {
132 	might_sleep();
133 
134 	/* GPIO can never have been requested */
135 	WARN_ON(1);
136 }
137 
138 static inline void gpio_free_array(const struct gpio *array, size_t num)
139 {
140 	might_sleep();
141 
142 	/* GPIO can never have been requested */
143 	WARN_ON(1);
144 }
145 
146 static inline int gpio_direction_input(unsigned gpio)
147 {
148 	return -ENOSYS;
149 }
150 
151 static inline int gpio_direction_output(unsigned gpio, int value)
152 {
153 	return -ENOSYS;
154 }
155 
156 static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
157 {
158 	return -ENOSYS;
159 }
160 
161 static inline int gpio_get_value(unsigned gpio)
162 {
163 	/* GPIO can never have been requested or set as {in,out}put */
164 	WARN_ON(1);
165 	return 0;
166 }
167 
168 static inline void gpio_set_value(unsigned gpio, int value)
169 {
170 	/* GPIO can never have been requested or set as output */
171 	WARN_ON(1);
172 }
173 
174 static inline int gpio_cansleep(unsigned gpio)
175 {
176 	/* GPIO can never have been requested or set as {in,out}put */
177 	WARN_ON(1);
178 	return 0;
179 }
180 
181 static inline int gpio_get_value_cansleep(unsigned gpio)
182 {
183 	/* GPIO can never have been requested or set as {in,out}put */
184 	WARN_ON(1);
185 	return 0;
186 }
187 
188 static inline void gpio_set_value_cansleep(unsigned gpio, int value)
189 {
190 	/* GPIO can never have been requested or set as output */
191 	WARN_ON(1);
192 }
193 
194 static inline int gpio_export(unsigned gpio, bool direction_may_change)
195 {
196 	/* GPIO can never have been requested or set as {in,out}put */
197 	WARN_ON(1);
198 	return -EINVAL;
199 }
200 
201 static inline int gpio_export_link(struct device *dev, const char *name,
202 				unsigned gpio)
203 {
204 	/* GPIO can never have been exported */
205 	WARN_ON(1);
206 	return -EINVAL;
207 }
208 
209 static inline void gpio_unexport(unsigned gpio)
210 {
211 	/* GPIO can never have been exported */
212 	WARN_ON(1);
213 }
214 
215 static inline int gpio_to_irq(unsigned gpio)
216 {
217 	/* GPIO can never have been requested or set as input */
218 	WARN_ON(1);
219 	return -EINVAL;
220 }
221 
222 static inline int irq_to_gpio(unsigned irq)
223 {
224 	/* irq can never have been returned from gpio_to_irq() */
225 	WARN_ON(1);
226 	return -EINVAL;
227 }
228 
229 static inline int devm_gpio_request(struct device *dev, unsigned gpio,
230 				    const char *label)
231 {
232 	WARN_ON(1);
233 	return -EINVAL;
234 }
235 
236 static inline int devm_gpio_request_one(struct device *dev, unsigned gpio,
237 					unsigned long flags, const char *label)
238 {
239 	WARN_ON(1);
240 	return -EINVAL;
241 }
242 
243 static inline void devm_gpio_free(struct device *dev, unsigned int gpio)
244 {
245 	WARN_ON(1);
246 }
247 
248 #endif /* ! CONFIG_GPIOLIB */
249 
250 #endif /* __LINUX_GPIO_H */
251