tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
18enum of_gpio_flags;
19
20struct 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 */
27struct acpi_gpio_info {
28 bool gpioint;
29 bool active_low;
30};
31
32/* gpio suffixes used for ACPI and device tree lookup */
33static const char * const gpio_suffixes[] = { "gpios", "gpio" };
34
35#ifdef CONFIG_ACPI
36void acpi_gpiochip_add(struct gpio_chip *chip);
37void acpi_gpiochip_remove(struct gpio_chip *chip);
38
39void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
40void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
41
42struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
43 const char *propname, int index,
44 struct acpi_gpio_info *info);
45struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
46 const char *propname, int index,
47 struct acpi_gpio_info *info);
48
49int acpi_gpio_count(struct device *dev, const char *con_id);
50#else
51static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
52static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
53
54static inline void
55acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
56
57static inline void
58acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
59
60static inline struct gpio_desc *
61acpi_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}
66static inline struct gpio_desc *
67acpi_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}
72static inline int acpi_gpio_count(struct device *dev, const char *con_id)
73{
74 return -ENODEV;
75}
76#endif
77
78struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
79 const char *list_name, int index, enum of_gpio_flags *flags);
80
81struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
82
83extern struct spinlock gpio_lock;
84extern struct list_head gpio_chips;
85
86struct 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
106int gpiod_request(struct gpio_desc *desc, const char *label);
107void gpiod_free(struct gpio_desc *desc);
108int 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 */
114static 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
157int gpiochip_sysfs_register(struct gpio_chip *chip);
158void gpiochip_sysfs_unregister(struct gpio_chip *chip);
159
160#else
161
162static inline int gpiochip_sysfs_register(struct gpio_chip *chip)
163{
164 return 0;
165}
166
167static inline void gpiochip_sysfs_unregister(struct gpio_chip *chip)
168{
169}
170
171#endif /* CONFIG_GPIO_SYSFS */
172
173#endif /* GPIOLIB_H */