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
20/**
21 * struct acpi_gpio_info - ACPI GPIO specific information
22 * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
23 * @active_low: in case of @gpioint, the pin is active low
24 */
25struct acpi_gpio_info {
26 bool gpioint;
27 bool active_low;
28};
29
30#ifdef CONFIG_ACPI
31void acpi_gpiochip_add(struct gpio_chip *chip);
32void acpi_gpiochip_remove(struct gpio_chip *chip);
33
34void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
35void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
36
37struct gpio_desc *acpi_get_gpiod_by_index(struct device *dev, int index,
38 struct acpi_gpio_info *info);
39#else
40static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
41static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
42
43static inline void
44acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
45
46static inline void
47acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
48
49static inline struct gpio_desc *
50acpi_get_gpiod_by_index(struct device *dev, int index,
51 struct acpi_gpio_info *info)
52{
53 return ERR_PTR(-ENOSYS);
54}
55#endif
56
57struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
58 const char *list_name, int index, enum of_gpio_flags *flags);
59
60struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
61
62extern struct spinlock gpio_lock;
63extern struct list_head gpio_chips;
64
65struct gpio_desc {
66 struct gpio_chip *chip;
67 unsigned long flags;
68/* flag symbols are bit numbers */
69#define FLAG_REQUESTED 0
70#define FLAG_IS_OUT 1
71#define FLAG_EXPORT 2 /* protected by sysfs_lock */
72#define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */
73#define FLAG_TRIG_FALL 4 /* trigger on falling edge */
74#define FLAG_TRIG_RISE 5 /* trigger on rising edge */
75#define FLAG_ACTIVE_LOW 6 /* value has active low */
76#define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */
77#define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */
78#define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */
79
80#define ID_SHIFT 16 /* add new flags before this one */
81
82#define GPIO_FLAGS_MASK ((1 << ID_SHIFT) - 1)
83#define GPIO_TRIGGER_MASK (BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE))
84
85 const char *label;
86};
87
88int gpiod_request(struct gpio_desc *desc, const char *label);
89void gpiod_free(struct gpio_desc *desc);
90
91/*
92 * Return the GPIO number of the passed descriptor relative to its chip
93 */
94static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
95{
96 return desc - &desc->chip->desc[0];
97}
98
99/* With descriptor prefix */
100
101#define gpiod_emerg(desc, fmt, ...) \
102 pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
103 ##__VA_ARGS__)
104#define gpiod_crit(desc, fmt, ...) \
105 pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
106 ##__VA_ARGS__)
107#define gpiod_err(desc, fmt, ...) \
108 pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
109 ##__VA_ARGS__)
110#define gpiod_warn(desc, fmt, ...) \
111 pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
112 ##__VA_ARGS__)
113#define gpiod_info(desc, fmt, ...) \
114 pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
115 ##__VA_ARGS__)
116#define gpiod_dbg(desc, fmt, ...) \
117 pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
118 ##__VA_ARGS__)
119
120/* With chip prefix */
121
122#define chip_emerg(chip, fmt, ...) \
123 pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
124#define chip_crit(chip, fmt, ...) \
125 pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
126#define chip_err(chip, fmt, ...) \
127 pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
128#define chip_warn(chip, fmt, ...) \
129 pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
130#define chip_info(chip, fmt, ...) \
131 pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
132#define chip_dbg(chip, fmt, ...) \
133 pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
134
135#ifdef CONFIG_GPIO_SYSFS
136
137int gpiochip_export(struct gpio_chip *chip);
138void gpiochip_unexport(struct gpio_chip *chip);
139
140#else
141
142static inline int gpiochip_export(struct gpio_chip *chip)
143{
144 return 0;
145}
146
147static inline void gpiochip_unexport(struct gpio_chip *chip)
148{
149}
150
151#endif /* CONFIG_GPIO_SYSFS */
152
153#endif /* GPIOLIB_H */