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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 */
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Internal GPIO functions.
4 *
5 * Copyright (C) 2013, Intel Corporation
6 * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
7 */
8
9#ifndef GPIOLIB_H
10#define GPIOLIB_H
11
12#include <linux/gpio/driver.h>
13#include <linux/gpio/consumer.h> /* for enum gpiod_flags */
14#include <linux/err.h>
15#include <linux/device.h>
16#include <linux/module.h>
17#include <linux/cdev.h>
18#include <linux/rwsem.h>
19
20#define GPIOCHIP_NAME "gpiochip"
21
22/**
23 * struct gpio_device - internal state container for GPIO devices
24 * @dev: the GPIO device struct
25 * @chrdev: character device for the GPIO device
26 * @id: numerical ID number for the GPIO chip
27 * @mockdev: class device used by the deprecated sysfs interface (may be
28 * NULL)
29 * @owner: helps prevent removal of modules exporting active GPIOs
30 * @chip: pointer to the corresponding gpiochip, holding static
31 * data for this device
32 * @descs: array of ngpio descriptors.
33 * @ngpio: the number of GPIO lines on this GPIO device, equal to the size
34 * of the @descs array.
35 * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned
36 * at device creation time.
37 * @label: a descriptive name for the GPIO device, such as the part number
38 * or name of the IP component in a System on Chip.
39 * @data: per-instance data assigned by the driver
40 * @list: links gpio_device:s together for traversal
41 * @notifier: used to notify subscribers about lines being requested, released
42 * or reconfigured
43 * @sem: protects the structure from a NULL-pointer dereference of @chip by
44 * user-space operations when the device gets unregistered during
45 * a hot-unplug event
46 * @pin_ranges: range of pins served by the GPIO driver
47 *
48 * This state container holds most of the runtime variable data
49 * for a GPIO device and can hold references and live on after the
50 * GPIO chip has been removed, if it is still being used from
51 * userspace.
52 */
53struct gpio_device {
54 struct device dev;
55 struct cdev chrdev;
56 int id;
57 struct device *mockdev;
58 struct module *owner;
59 struct gpio_chip *chip;
60 struct gpio_desc *descs;
61 int base;
62 u16 ngpio;
63 const char *label;
64 void *data;
65 struct list_head list;
66 struct blocking_notifier_head notifier;
67 struct rw_semaphore sem;
68
69#ifdef CONFIG_PINCTRL
70 /*
71 * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
72 * describe the actual pin range which they serve in an SoC. This
73 * information would be used by pinctrl subsystem to configure
74 * corresponding pins for gpio usage.
75 */
76 struct list_head pin_ranges;
77#endif
78};
79
80static inline struct gpio_device *to_gpio_device(struct device *dev)
81{
82 return container_of(dev, struct gpio_device, dev);
83}
84
85/* gpio suffixes used for ACPI and device tree lookup */
86static __maybe_unused const char * const gpio_suffixes[] = { "gpios", "gpio" };
87
88/**
89 * struct gpio_array - Opaque descriptor for a structure of GPIO array attributes
90 *
91 * @desc: Array of pointers to the GPIO descriptors
92 * @size: Number of elements in desc
93 * @chip: Parent GPIO chip
94 * @get_mask: Get mask used in fastpath
95 * @set_mask: Set mask used in fastpath
96 * @invert_mask: Invert mask used in fastpath
97 *
98 * This structure is attached to struct gpiod_descs obtained from
99 * gpiod_get_array() and can be passed back to get/set array functions in order
100 * to activate fast processing path if applicable.
101 */
102struct gpio_array {
103 struct gpio_desc **desc;
104 unsigned int size;
105 struct gpio_chip *chip;
106 unsigned long *get_mask;
107 unsigned long *set_mask;
108 unsigned long invert_mask[];
109};
110
111struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc, unsigned int hwnum);
112
113#define for_each_gpio_desc(gc, desc) \
114 for (unsigned int __i = 0; \
115 __i < gc->ngpio && (desc = gpiochip_get_desc(gc, __i)); \
116 __i++) \
117
118#define for_each_gpio_desc_with_flag(gc, desc, flag) \
119 for_each_gpio_desc(gc, desc) \
120 if (!test_bit(flag, &desc->flags)) {} else
121
122int gpiod_get_array_value_complex(bool raw, bool can_sleep,
123 unsigned int array_size,
124 struct gpio_desc **desc_array,
125 struct gpio_array *array_info,
126 unsigned long *value_bitmap);
127int gpiod_set_array_value_complex(bool raw, bool can_sleep,
128 unsigned int array_size,
129 struct gpio_desc **desc_array,
130 struct gpio_array *array_info,
131 unsigned long *value_bitmap);
132
133extern spinlock_t gpio_lock;
134extern struct list_head gpio_devices;
135
136
137/**
138 * struct gpio_desc - Opaque descriptor for a GPIO
139 *
140 * @gdev: Pointer to the parent GPIO device
141 * @flags: Binary descriptor flags
142 * @label: Name of the consumer
143 * @name: Line name
144 * @hog: Pointer to the device node that hogs this line (if any)
145 * @debounce_period_us: Debounce period in microseconds
146 *
147 * These are obtained using gpiod_get() and are preferable to the old
148 * integer-based handles.
149 *
150 * Contrary to integers, a pointer to a &struct gpio_desc is guaranteed to be
151 * valid until the GPIO is released.
152 */
153struct gpio_desc {
154 struct gpio_device *gdev;
155 unsigned long flags;
156/* flag symbols are bit numbers */
157#define FLAG_REQUESTED 0
158#define FLAG_IS_OUT 1
159#define FLAG_EXPORT 2 /* protected by sysfs_lock */
160#define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */
161#define FLAG_ACTIVE_LOW 6 /* value has active low */
162#define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */
163#define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */
164#define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */
165#define FLAG_IRQ_IS_ENABLED 10 /* GPIO is connected to an enabled IRQ */
166#define FLAG_IS_HOGGED 11 /* GPIO is hogged */
167#define FLAG_TRANSITORY 12 /* GPIO may lose value in sleep or reset */
168#define FLAG_PULL_UP 13 /* GPIO has pull up enabled */
169#define FLAG_PULL_DOWN 14 /* GPIO has pull down enabled */
170#define FLAG_BIAS_DISABLE 15 /* GPIO has pull disabled */
171#define FLAG_EDGE_RISING 16 /* GPIO CDEV detects rising edge events */
172#define FLAG_EDGE_FALLING 17 /* GPIO CDEV detects falling edge events */
173#define FLAG_EVENT_CLOCK_REALTIME 18 /* GPIO CDEV reports REALTIME timestamps in events */
174#define FLAG_EVENT_CLOCK_HTE 19 /* GPIO CDEV reports hardware timestamps in events */
175
176 /* Connection label */
177 const char *label;
178 /* Name of the GPIO */
179 const char *name;
180#ifdef CONFIG_OF_DYNAMIC
181 struct device_node *hog;
182#endif
183#ifdef CONFIG_GPIO_CDEV
184 /* debounce period in microseconds */
185 unsigned int debounce_period_us;
186#endif
187};
188
189#define gpiod_not_found(desc) (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT)
190
191int gpiod_request(struct gpio_desc *desc, const char *label);
192void gpiod_free(struct gpio_desc *desc);
193
194static inline int gpiod_request_user(struct gpio_desc *desc, const char *label)
195{
196 int ret;
197
198 ret = gpiod_request(desc, label);
199 if (ret == -EPROBE_DEFER)
200 ret = -ENODEV;
201
202 return ret;
203}
204
205int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
206 unsigned long lflags, enum gpiod_flags dflags);
207int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce);
208int gpiod_hog(struct gpio_desc *desc, const char *name,
209 unsigned long lflags, enum gpiod_flags dflags);
210
211/*
212 * Return the GPIO number of the passed descriptor relative to its chip
213 */
214static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
215{
216 return desc - &desc->gdev->descs[0];
217}
218
219/* With descriptor prefix */
220
221#define gpiod_emerg(desc, fmt, ...) \
222 pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
223 ##__VA_ARGS__)
224#define gpiod_crit(desc, fmt, ...) \
225 pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
226 ##__VA_ARGS__)
227#define gpiod_err(desc, fmt, ...) \
228 pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
229 ##__VA_ARGS__)
230#define gpiod_warn(desc, fmt, ...) \
231 pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
232 ##__VA_ARGS__)
233#define gpiod_info(desc, fmt, ...) \
234 pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
235 ##__VA_ARGS__)
236#define gpiod_dbg(desc, fmt, ...) \
237 pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
238 ##__VA_ARGS__)
239
240/* With chip prefix */
241
242#define chip_emerg(gc, fmt, ...) \
243 dev_emerg(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
244#define chip_crit(gc, fmt, ...) \
245 dev_crit(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
246#define chip_err(gc, fmt, ...) \
247 dev_err(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
248#define chip_warn(gc, fmt, ...) \
249 dev_warn(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
250#define chip_info(gc, fmt, ...) \
251 dev_info(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
252#define chip_dbg(gc, fmt, ...) \
253 dev_dbg(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
254
255#endif /* GPIOLIB_H */