xref: /linux/drivers/gpio/gpiolib.h (revision 8c749ce93ee69e789e46b3be98de9e0cbfcf8ed8)
1 /*
2  * Internal GPIO functions.
3  *
4  * Copyright (C) 2013, Intel Corporation
5  * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #ifndef GPIOLIB_H
13 #define GPIOLIB_H
14 
15 #include <linux/err.h>
16 #include <linux/device.h>
17 
18 enum of_gpio_flags;
19 enum gpiod_flags;
20 struct acpi_device;
21 
22 /**
23  * struct acpi_gpio_info - ACPI GPIO specific information
24  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
25  * @active_low: in case of @gpioint, the pin is active low
26  */
27 struct acpi_gpio_info {
28 	bool gpioint;
29 	int polarity;
30 	int triggering;
31 };
32 
33 /* gpio suffixes used for ACPI and device tree lookup */
34 static const char * const gpio_suffixes[] = { "gpios", "gpio" };
35 
36 #ifdef CONFIG_ACPI
37 void acpi_gpiochip_add(struct gpio_chip *chip);
38 void acpi_gpiochip_remove(struct gpio_chip *chip);
39 
40 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
41 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
42 
43 struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
44 					  const char *propname, int index,
45 					  struct acpi_gpio_info *info);
46 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
47 				      const char *propname, int index,
48 				      struct acpi_gpio_info *info);
49 
50 int acpi_gpio_count(struct device *dev, const char *con_id);
51 
52 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id);
53 #else
54 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
55 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
56 
57 static inline void
58 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
59 
60 static inline void
61 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
62 
63 static inline struct gpio_desc *
64 acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname,
65 			int index, struct acpi_gpio_info *info)
66 {
67 	return ERR_PTR(-ENOSYS);
68 }
69 static inline struct gpio_desc *
70 acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
71 		    int index, struct acpi_gpio_info *info)
72 {
73 	return ERR_PTR(-ENXIO);
74 }
75 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
76 {
77 	return -ENODEV;
78 }
79 
80 static inline bool acpi_can_fallback_to_crs(struct acpi_device *adev,
81 					    const char *con_id)
82 {
83 	return false;
84 }
85 #endif
86 
87 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
88 		   const char *list_name, int index, enum of_gpio_flags *flags);
89 
90 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
91 
92 extern struct spinlock gpio_lock;
93 extern struct list_head gpio_chips;
94 
95 struct gpio_desc {
96 	struct gpio_chip	*chip;
97 	unsigned long		flags;
98 /* flag symbols are bit numbers */
99 #define FLAG_REQUESTED	0
100 #define FLAG_IS_OUT	1
101 #define FLAG_EXPORT	2	/* protected by sysfs_lock */
102 #define FLAG_SYSFS	3	/* exported via /sys/class/gpio/control */
103 #define FLAG_ACTIVE_LOW	6	/* value has active low */
104 #define FLAG_OPEN_DRAIN	7	/* Gpio is open drain type */
105 #define FLAG_OPEN_SOURCE 8	/* Gpio is open source type */
106 #define FLAG_USED_AS_IRQ 9	/* GPIO is connected to an IRQ */
107 #define FLAG_IS_HOGGED	11	/* GPIO is hogged */
108 
109 	/* Connection label */
110 	const char		*label;
111 	/* Name of the GPIO */
112 	const char		*name;
113 };
114 
115 int gpiod_request(struct gpio_desc *desc, const char *label);
116 void gpiod_free(struct gpio_desc *desc);
117 int gpiod_hog(struct gpio_desc *desc, const char *name,
118 		unsigned long lflags, enum gpiod_flags dflags);
119 
120 /*
121  * Return the GPIO number of the passed descriptor relative to its chip
122  */
123 static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
124 {
125 	return desc - &desc->chip->desc[0];
126 }
127 
128 /* With descriptor prefix */
129 
130 #define gpiod_emerg(desc, fmt, ...)					       \
131 	pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
132 		 ##__VA_ARGS__)
133 #define gpiod_crit(desc, fmt, ...)					       \
134 	pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
135 		 ##__VA_ARGS__)
136 #define gpiod_err(desc, fmt, ...)					       \
137 	pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
138 		 ##__VA_ARGS__)
139 #define gpiod_warn(desc, fmt, ...)					       \
140 	pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
141 		 ##__VA_ARGS__)
142 #define gpiod_info(desc, fmt, ...)					       \
143 	pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
144 		 ##__VA_ARGS__)
145 #define gpiod_dbg(desc, fmt, ...)					       \
146 	pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
147 		 ##__VA_ARGS__)
148 
149 /* With chip prefix */
150 
151 #define chip_emerg(chip, fmt, ...)					\
152 	pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
153 #define chip_crit(chip, fmt, ...)					\
154 	pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
155 #define chip_err(chip, fmt, ...)					\
156 	pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
157 #define chip_warn(chip, fmt, ...)					\
158 	pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
159 #define chip_info(chip, fmt, ...)					\
160 	pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
161 #define chip_dbg(chip, fmt, ...)					\
162 	pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
163 
164 #ifdef CONFIG_GPIO_SYSFS
165 
166 int gpiochip_sysfs_register(struct gpio_chip *chip);
167 void gpiochip_sysfs_unregister(struct gpio_chip *chip);
168 
169 #else
170 
171 static inline int gpiochip_sysfs_register(struct gpio_chip *chip)
172 {
173 	return 0;
174 }
175 
176 static inline void gpiochip_sysfs_unregister(struct gpio_chip *chip)
177 {
178 }
179 
180 #endif /* CONFIG_GPIO_SYSFS */
181 
182 #endif /* GPIOLIB_H */
183