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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/gpio/driver.h>
16#include <linux/err.h>
17#include <linux/device.h>
18#include <linux/module.h>
19#include <linux/cdev.h>
20
21enum of_gpio_flags;
22enum gpiod_flags;
23struct acpi_device;
24
25/**
26 * struct gpio_device - internal state container for GPIO devices
27 * @id: numerical ID number for the GPIO chip
28 * @dev: the GPIO device struct
29 * @chrdev: character device for the GPIO device
30 * @mockdev: class device used by the deprecated sysfs interface (may be
31 * NULL)
32 * @owner: helps prevent removal of modules exporting active GPIOs
33 * @chip: pointer to the corresponding gpiochip, holding static
34 * data for this device
35 * @descs: array of ngpio descriptors.
36 * @ngpio: the number of GPIO lines on this GPIO device, equal to the size
37 * of the @descs array.
38 * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned
39 * at device creation time.
40 * @label: a descriptive name for the GPIO device, such as the part number
41 * or name of the IP component in a System on Chip.
42 * @data: per-instance data assigned by the driver
43 * @list: links gpio_device:s together for traversal
44 *
45 * This state container holds most of the runtime variable data
46 * for a GPIO device and can hold references and live on after the
47 * GPIO chip has been removed, if it is still being used from
48 * userspace.
49 */
50struct gpio_device {
51 int id;
52 struct device dev;
53 struct cdev chrdev;
54 struct device *mockdev;
55 struct module *owner;
56 struct gpio_chip *chip;
57 struct gpio_desc *descs;
58 int base;
59 u16 ngpio;
60 char *label;
61 void *data;
62 struct list_head list;
63
64#ifdef CONFIG_PINCTRL
65 /*
66 * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
67 * describe the actual pin range which they serve in an SoC. This
68 * information would be used by pinctrl subsystem to configure
69 * corresponding pins for gpio usage.
70 */
71 struct list_head pin_ranges;
72#endif
73};
74
75/**
76 * struct acpi_gpio_info - ACPI GPIO specific information
77 * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
78 * @active_low: in case of @gpioint, the pin is active low
79 */
80struct acpi_gpio_info {
81 bool gpioint;
82 int polarity;
83 int triggering;
84};
85
86/* gpio suffixes used for ACPI and device tree lookup */
87static const char * const gpio_suffixes[] = { "gpios", "gpio" };
88
89#ifdef CONFIG_ACPI
90void acpi_gpiochip_add(struct gpio_chip *chip);
91void acpi_gpiochip_remove(struct gpio_chip *chip);
92
93void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
94void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
95
96struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
97 const char *propname, int index,
98 struct acpi_gpio_info *info);
99struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
100 const char *propname, int index,
101 struct acpi_gpio_info *info);
102
103int acpi_gpio_count(struct device *dev, const char *con_id);
104
105bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id);
106#else
107static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
108static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
109
110static inline void
111acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
112
113static inline void
114acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
115
116static inline struct gpio_desc *
117acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname,
118 int index, struct acpi_gpio_info *info)
119{
120 return ERR_PTR(-ENOSYS);
121}
122static inline struct gpio_desc *
123acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
124 int index, struct acpi_gpio_info *info)
125{
126 return ERR_PTR(-ENXIO);
127}
128static inline int acpi_gpio_count(struct device *dev, const char *con_id)
129{
130 return -ENODEV;
131}
132
133static inline bool acpi_can_fallback_to_crs(struct acpi_device *adev,
134 const char *con_id)
135{
136 return false;
137}
138#endif
139
140struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
141 const char *list_name, int index, enum of_gpio_flags *flags);
142
143struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
144
145extern struct spinlock gpio_lock;
146extern struct list_head gpio_devices;
147
148struct gpio_desc {
149 struct gpio_device *gdev;
150 unsigned long flags;
151/* flag symbols are bit numbers */
152#define FLAG_REQUESTED 0
153#define FLAG_IS_OUT 1
154#define FLAG_EXPORT 2 /* protected by sysfs_lock */
155#define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */
156#define FLAG_ACTIVE_LOW 6 /* value has active low */
157#define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */
158#define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */
159#define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */
160#define FLAG_IS_HOGGED 11 /* GPIO is hogged */
161
162 /* Connection label */
163 const char *label;
164 /* Name of the GPIO */
165 const char *name;
166};
167
168int gpiod_request(struct gpio_desc *desc, const char *label);
169void gpiod_free(struct gpio_desc *desc);
170int gpiod_hog(struct gpio_desc *desc, const char *name,
171 unsigned long lflags, enum gpiod_flags dflags);
172
173/*
174 * Return the GPIO number of the passed descriptor relative to its chip
175 */
176static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
177{
178 return desc - &desc->gdev->descs[0];
179}
180
181/* With descriptor prefix */
182
183#define gpiod_emerg(desc, fmt, ...) \
184 pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
185 ##__VA_ARGS__)
186#define gpiod_crit(desc, fmt, ...) \
187 pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
188 ##__VA_ARGS__)
189#define gpiod_err(desc, fmt, ...) \
190 pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
191 ##__VA_ARGS__)
192#define gpiod_warn(desc, fmt, ...) \
193 pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
194 ##__VA_ARGS__)
195#define gpiod_info(desc, fmt, ...) \
196 pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
197 ##__VA_ARGS__)
198#define gpiod_dbg(desc, fmt, ...) \
199 pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
200 ##__VA_ARGS__)
201
202/* With chip prefix */
203
204#define chip_emerg(chip, fmt, ...) \
205 dev_emerg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
206#define chip_crit(chip, fmt, ...) \
207 dev_crit(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
208#define chip_err(chip, fmt, ...) \
209 dev_err(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
210#define chip_warn(chip, fmt, ...) \
211 dev_warn(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
212#define chip_info(chip, fmt, ...) \
213 dev_info(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
214#define chip_dbg(chip, fmt, ...) \
215 dev_dbg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
216
217#ifdef CONFIG_GPIO_SYSFS
218
219int gpiochip_sysfs_register(struct gpio_device *gdev);
220void gpiochip_sysfs_unregister(struct gpio_device *gdev);
221
222#else
223
224static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
225{
226 return 0;
227}
228
229static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
230{
231}
232
233#endif /* CONFIG_GPIO_SYSFS */
234
235#endif /* GPIOLIB_H */