xref: /openbmc/linux/drivers/gpio/gpiolib.h (revision 6a613ac6)
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 
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 	bool active_low;
30 };
31 
32 /* gpio suffixes used for ACPI and device tree lookup */
33 static const char * const gpio_suffixes[] = { "gpios", "gpio" };
34 
35 #ifdef CONFIG_ACPI
36 void acpi_gpiochip_add(struct gpio_chip *chip);
37 void acpi_gpiochip_remove(struct gpio_chip *chip);
38 
39 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
40 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
41 
42 struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
43 					  const char *propname, int index,
44 					  struct acpi_gpio_info *info);
45 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
46 				      const char *propname, int index,
47 				      struct acpi_gpio_info *info);
48 
49 int acpi_gpio_count(struct device *dev, const char *con_id);
50 #else
51 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
52 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
53 
54 static inline void
55 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
56 
57 static inline void
58 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
59 
60 static inline struct gpio_desc *
61 acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname,
62 			int index, struct acpi_gpio_info *info)
63 {
64 	return ERR_PTR(-ENOSYS);
65 }
66 static inline struct gpio_desc *
67 acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
68 		    int index, struct acpi_gpio_info *info)
69 {
70 	return ERR_PTR(-ENXIO);
71 }
72 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
73 {
74 	return -ENODEV;
75 }
76 #endif
77 
78 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
79 		   const char *list_name, int index, enum of_gpio_flags *flags);
80 
81 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
82 
83 extern struct spinlock gpio_lock;
84 extern struct list_head gpio_chips;
85 
86 struct gpio_desc {
87 	struct gpio_chip	*chip;
88 	unsigned long		flags;
89 /* flag symbols are bit numbers */
90 #define FLAG_REQUESTED	0
91 #define FLAG_IS_OUT	1
92 #define FLAG_EXPORT	2	/* protected by sysfs_lock */
93 #define FLAG_SYSFS	3	/* exported via /sys/class/gpio/control */
94 #define FLAG_ACTIVE_LOW	6	/* value has active low */
95 #define FLAG_OPEN_DRAIN	7	/* Gpio is open drain type */
96 #define FLAG_OPEN_SOURCE 8	/* Gpio is open source type */
97 #define FLAG_USED_AS_IRQ 9	/* GPIO is connected to an IRQ */
98 #define FLAG_IS_HOGGED	11	/* GPIO is hogged */
99 
100 	/* Connection label */
101 	const char		*label;
102 	/* Name of the GPIO */
103 	const char		*name;
104 };
105 
106 int gpiod_request(struct gpio_desc *desc, const char *label);
107 void gpiod_free(struct gpio_desc *desc);
108 int gpiod_hog(struct gpio_desc *desc, const char *name,
109 		unsigned long lflags, enum gpiod_flags dflags);
110 
111 /*
112  * Return the GPIO number of the passed descriptor relative to its chip
113  */
114 static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
115 {
116 	return desc - &desc->chip->desc[0];
117 }
118 
119 /* With descriptor prefix */
120 
121 #define gpiod_emerg(desc, fmt, ...)					       \
122 	pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
123 		 ##__VA_ARGS__)
124 #define gpiod_crit(desc, fmt, ...)					       \
125 	pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
126 		 ##__VA_ARGS__)
127 #define gpiod_err(desc, fmt, ...)					       \
128 	pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
129 		 ##__VA_ARGS__)
130 #define gpiod_warn(desc, fmt, ...)					       \
131 	pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
132 		 ##__VA_ARGS__)
133 #define gpiod_info(desc, fmt, ...)					       \
134 	pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
135 		 ##__VA_ARGS__)
136 #define gpiod_dbg(desc, fmt, ...)					       \
137 	pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
138 		 ##__VA_ARGS__)
139 
140 /* With chip prefix */
141 
142 #define chip_emerg(chip, fmt, ...)					\
143 	pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
144 #define chip_crit(chip, fmt, ...)					\
145 	pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
146 #define chip_err(chip, fmt, ...)					\
147 	pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
148 #define chip_warn(chip, fmt, ...)					\
149 	pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
150 #define chip_info(chip, fmt, ...)					\
151 	pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
152 #define chip_dbg(chip, fmt, ...)					\
153 	pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
154 
155 #ifdef CONFIG_GPIO_SYSFS
156 
157 int gpiochip_sysfs_register(struct gpio_chip *chip);
158 void gpiochip_sysfs_unregister(struct gpio_chip *chip);
159 
160 #else
161 
162 static inline int gpiochip_sysfs_register(struct gpio_chip *chip)
163 {
164 	return 0;
165 }
166 
167 static inline void gpiochip_sysfs_unregister(struct gpio_chip *chip)
168 {
169 }
170 
171 #endif /* CONFIG_GPIO_SYSFS */
172 
173 #endif /* GPIOLIB_H */
174