xref: /openbmc/linux/include/linux/gpio.h (revision 78beef62)
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 #include <linux/pinctrl/pinctrl.h>
106 
107 struct device;
108 struct gpio_chip;
109 struct pinctrl_dev;
110 
111 static inline bool gpio_is_valid(int number)
112 {
113 	return false;
114 }
115 
116 static inline int gpio_request(unsigned gpio, const char *label)
117 {
118 	return -ENOSYS;
119 }
120 
121 static inline int gpio_request_one(unsigned gpio,
122 					unsigned long flags, const char *label)
123 {
124 	return -ENOSYS;
125 }
126 
127 static inline int gpio_request_array(const struct gpio *array, size_t num)
128 {
129 	return -ENOSYS;
130 }
131 
132 static inline void gpio_free(unsigned gpio)
133 {
134 	might_sleep();
135 
136 	/* GPIO can never have been requested */
137 	WARN_ON(1);
138 }
139 
140 static inline void gpio_free_array(const struct gpio *array, size_t num)
141 {
142 	might_sleep();
143 
144 	/* GPIO can never have been requested */
145 	WARN_ON(1);
146 }
147 
148 static inline int gpio_direction_input(unsigned gpio)
149 {
150 	return -ENOSYS;
151 }
152 
153 static inline int gpio_direction_output(unsigned gpio, int value)
154 {
155 	return -ENOSYS;
156 }
157 
158 static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
159 {
160 	return -ENOSYS;
161 }
162 
163 static inline int gpio_get_value(unsigned gpio)
164 {
165 	/* GPIO can never have been requested or set as {in,out}put */
166 	WARN_ON(1);
167 	return 0;
168 }
169 
170 static inline void gpio_set_value(unsigned gpio, int value)
171 {
172 	/* GPIO can never have been requested or set as output */
173 	WARN_ON(1);
174 }
175 
176 static inline int gpio_cansleep(unsigned gpio)
177 {
178 	/* GPIO can never have been requested or set as {in,out}put */
179 	WARN_ON(1);
180 	return 0;
181 }
182 
183 static inline int gpio_get_value_cansleep(unsigned gpio)
184 {
185 	/* GPIO can never have been requested or set as {in,out}put */
186 	WARN_ON(1);
187 	return 0;
188 }
189 
190 static inline void gpio_set_value_cansleep(unsigned gpio, int value)
191 {
192 	/* GPIO can never have been requested or set as output */
193 	WARN_ON(1);
194 }
195 
196 static inline int gpio_export(unsigned gpio, bool direction_may_change)
197 {
198 	/* GPIO can never have been requested or set as {in,out}put */
199 	WARN_ON(1);
200 	return -EINVAL;
201 }
202 
203 static inline int gpio_export_link(struct device *dev, const char *name,
204 				unsigned gpio)
205 {
206 	/* GPIO can never have been exported */
207 	WARN_ON(1);
208 	return -EINVAL;
209 }
210 
211 static inline void gpio_unexport(unsigned gpio)
212 {
213 	/* GPIO can never have been exported */
214 	WARN_ON(1);
215 }
216 
217 static inline int gpio_to_irq(unsigned gpio)
218 {
219 	/* GPIO can never have been requested or set as input */
220 	WARN_ON(1);
221 	return -EINVAL;
222 }
223 
224 static inline int irq_to_gpio(unsigned irq)
225 {
226 	/* irq can never have been returned from gpio_to_irq() */
227 	WARN_ON(1);
228 	return -EINVAL;
229 }
230 
231 static inline int devm_gpio_request(struct device *dev, unsigned gpio,
232 				    const char *label)
233 {
234 	WARN_ON(1);
235 	return -EINVAL;
236 }
237 
238 static inline int devm_gpio_request_one(struct device *dev, unsigned gpio,
239 					unsigned long flags, const char *label)
240 {
241 	WARN_ON(1);
242 	return -EINVAL;
243 }
244 
245 static inline void devm_gpio_free(struct device *dev, unsigned int gpio)
246 {
247 	WARN_ON(1);
248 }
249 
250 #endif /* ! CONFIG_GPIOLIB */
251 
252 #endif /* __LINUX_GPIO_H */
253