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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
19#define GPIOCHIP_NAME "gpiochip"
20
21/**
22 * struct gpio_device - internal state container for GPIO devices
23 * @id: numerical ID number for the GPIO chip
24 * @dev: the GPIO device struct
25 * @chrdev: character device for the GPIO device
26 * @mockdev: class device used by the deprecated sysfs interface (may be
27 * NULL)
28 * @owner: helps prevent removal of modules exporting active GPIOs
29 * @chip: pointer to the corresponding gpiochip, holding static
30 * data for this device
31 * @descs: array of ngpio descriptors.
32 * @ngpio: the number of GPIO lines on this GPIO device, equal to the size
33 * of the @descs array.
34 * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned
35 * at device creation time.
36 * @label: a descriptive name for the GPIO device, such as the part number
37 * or name of the IP component in a System on Chip.
38 * @data: per-instance data assigned by the driver
39 * @list: links gpio_device:s together for traversal
40 *
41 * This state container holds most of the runtime variable data
42 * for a GPIO device and can hold references and live on after the
43 * GPIO chip has been removed, if it is still being used from
44 * userspace.
45 */
46struct gpio_device {
47 int id;
48 struct device dev;
49 struct cdev chrdev;
50 struct device *mockdev;
51 struct module *owner;
52 struct gpio_chip *chip;
53 struct gpio_desc *descs;
54 int base;
55 u16 ngpio;
56 const char *label;
57 void *data;
58 struct list_head list;
59 struct blocking_notifier_head notifier;
60
61#ifdef CONFIG_PINCTRL
62 /*
63 * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
64 * describe the actual pin range which they serve in an SoC. This
65 * information would be used by pinctrl subsystem to configure
66 * corresponding pins for gpio usage.
67 */
68 struct list_head pin_ranges;
69#endif
70};
71
72/* gpio suffixes used for ACPI and device tree lookup */
73static __maybe_unused const char * const gpio_suffixes[] = { "gpios", "gpio" };
74
75struct gpio_array {
76 struct gpio_desc **desc;
77 unsigned int size;
78 struct gpio_chip *chip;
79 unsigned long *get_mask;
80 unsigned long *set_mask;
81 unsigned long invert_mask[];
82};
83
84struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc, unsigned int hwnum);
85int gpiod_get_array_value_complex(bool raw, bool can_sleep,
86 unsigned int array_size,
87 struct gpio_desc **desc_array,
88 struct gpio_array *array_info,
89 unsigned long *value_bitmap);
90int gpiod_set_array_value_complex(bool raw, bool can_sleep,
91 unsigned int array_size,
92 struct gpio_desc **desc_array,
93 struct gpio_array *array_info,
94 unsigned long *value_bitmap);
95
96extern spinlock_t gpio_lock;
97extern struct list_head gpio_devices;
98
99struct gpio_desc {
100 struct gpio_device *gdev;
101 unsigned long flags;
102/* flag symbols are bit numbers */
103#define FLAG_REQUESTED 0
104#define FLAG_IS_OUT 1
105#define FLAG_EXPORT 2 /* protected by sysfs_lock */
106#define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */
107#define FLAG_ACTIVE_LOW 6 /* value has active low */
108#define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */
109#define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */
110#define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */
111#define FLAG_IRQ_IS_ENABLED 10 /* GPIO is connected to an enabled IRQ */
112#define FLAG_IS_HOGGED 11 /* GPIO is hogged */
113#define FLAG_TRANSITORY 12 /* GPIO may lose value in sleep or reset */
114#define FLAG_PULL_UP 13 /* GPIO has pull up enabled */
115#define FLAG_PULL_DOWN 14 /* GPIO has pull down enabled */
116#define FLAG_BIAS_DISABLE 15 /* GPIO has pull disabled */
117
118 /* Connection label */
119 const char *label;
120 /* Name of the GPIO */
121 const char *name;
122#ifdef CONFIG_OF_DYNAMIC
123 struct device_node *hog;
124#endif
125};
126
127int gpiod_request(struct gpio_desc *desc, const char *label);
128void gpiod_free(struct gpio_desc *desc);
129int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
130 unsigned long lflags, enum gpiod_flags dflags);
131int gpiod_hog(struct gpio_desc *desc, const char *name,
132 unsigned long lflags, enum gpiod_flags dflags);
133
134/*
135 * Return the GPIO number of the passed descriptor relative to its chip
136 */
137static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
138{
139 return desc - &desc->gdev->descs[0];
140}
141
142/* With descriptor prefix */
143
144#define gpiod_emerg(desc, fmt, ...) \
145 pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
146 ##__VA_ARGS__)
147#define gpiod_crit(desc, fmt, ...) \
148 pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
149 ##__VA_ARGS__)
150#define gpiod_err(desc, fmt, ...) \
151 pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
152 ##__VA_ARGS__)
153#define gpiod_warn(desc, fmt, ...) \
154 pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
155 ##__VA_ARGS__)
156#define gpiod_info(desc, fmt, ...) \
157 pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
158 ##__VA_ARGS__)
159#define gpiod_dbg(desc, fmt, ...) \
160 pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
161 ##__VA_ARGS__)
162
163/* With chip prefix */
164
165#define chip_emerg(gc, fmt, ...) \
166 dev_emerg(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
167#define chip_crit(gc, fmt, ...) \
168 dev_crit(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
169#define chip_err(gc, fmt, ...) \
170 dev_err(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
171#define chip_warn(gc, fmt, ...) \
172 dev_warn(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
173#define chip_info(gc, fmt, ...) \
174 dev_info(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
175#define chip_dbg(gc, fmt, ...) \
176 dev_dbg(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
177
178#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/cdev.h>
13#include <linux/device.h>
14#include <linux/err.h>
15#include <linux/gpio/consumer.h> /* for enum gpiod_flags */
16#include <linux/gpio/driver.h>
17#include <linux/module.h>
18#include <linux/notifier.h>
19#include <linux/srcu.h>
20#include <linux/workqueue.h>
21
22#define GPIOCHIP_NAME "gpiochip"
23
24/**
25 * struct gpio_device - internal state container for GPIO devices
26 * @dev: the GPIO device struct
27 * @chrdev: character device for the GPIO device
28 * @id: numerical ID number for the GPIO chip
29 * @mockdev: class device used by the deprecated sysfs interface (may be
30 * NULL)
31 * @owner: helps prevent removal of modules exporting active GPIOs
32 * @chip: pointer to the corresponding gpiochip, holding static
33 * data for this device
34 * @descs: array of ngpio descriptors.
35 * @desc_srcu: ensures consistent state of GPIO descriptors exposed to users
36 * @ngpio: the number of GPIO lines on this GPIO device, equal to the size
37 * of the @descs array.
38 * @can_sleep: indicate whether the GPIO chip driver's callbacks can sleep
39 * implying that they cannot be used from atomic context
40 * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned
41 * at device creation time.
42 * @label: a descriptive name for the GPIO device, such as the part number
43 * or name of the IP component in a System on Chip.
44 * @data: per-instance data assigned by the driver
45 * @list: links gpio_device:s together for traversal
46 * @line_state_notifier: used to notify subscribers about lines being
47 * requested, released or reconfigured
48 * @line_state_wq: used to emit line state events from a separate thread in
49 * process context
50 * @device_notifier: used to notify character device wait queues about the GPIO
51 * device being unregistered
52 * @srcu: protects the pointer to the underlying GPIO chip
53 * @pin_ranges: range of pins served by the GPIO driver
54 *
55 * This state container holds most of the runtime variable data
56 * for a GPIO device and can hold references and live on after the
57 * GPIO chip has been removed, if it is still being used from
58 * userspace.
59 */
60struct gpio_device {
61 struct device dev;
62 struct cdev chrdev;
63 int id;
64 struct device *mockdev;
65 struct module *owner;
66 struct gpio_chip __rcu *chip;
67 struct gpio_desc *descs;
68 struct srcu_struct desc_srcu;
69 unsigned int base;
70 u16 ngpio;
71 bool can_sleep;
72 const char *label;
73 void *data;
74 struct list_head list;
75 struct atomic_notifier_head line_state_notifier;
76 struct workqueue_struct *line_state_wq;
77 struct blocking_notifier_head device_notifier;
78 struct srcu_struct srcu;
79
80#ifdef CONFIG_PINCTRL
81 /*
82 * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
83 * describe the actual pin range which they serve in an SoC. This
84 * information would be used by pinctrl subsystem to configure
85 * corresponding pins for gpio usage.
86 */
87 struct list_head pin_ranges;
88#endif
89};
90
91static inline struct gpio_device *to_gpio_device(struct device *dev)
92{
93 return container_of(dev, struct gpio_device, dev);
94}
95
96/* GPIO suffixes used for ACPI and device tree lookup */
97extern const char *const gpio_suffixes[];
98
99#define for_each_gpio_property_name(propname, con_id) \
100 for (const char * const *__suffixes = gpio_suffixes; \
101 *__suffixes && ({ \
102 const char *__gs = *__suffixes; \
103 \
104 if (con_id) \
105 snprintf(propname, sizeof(propname), "%s-%s", con_id, __gs); \
106 else \
107 snprintf(propname, sizeof(propname), "%s", __gs); \
108 1; \
109 }); \
110 __suffixes++)
111
112/**
113 * struct gpio_array - Opaque descriptor for a structure of GPIO array attributes
114 *
115 * @desc: Array of pointers to the GPIO descriptors
116 * @size: Number of elements in desc
117 * @gdev: Parent GPIO device
118 * @get_mask: Get mask used in fastpath
119 * @set_mask: Set mask used in fastpath
120 * @invert_mask: Invert mask used in fastpath
121 *
122 * This structure is attached to struct gpiod_descs obtained from
123 * gpiod_get_array() and can be passed back to get/set array functions in order
124 * to activate fast processing path if applicable.
125 */
126struct gpio_array {
127 struct gpio_desc **desc;
128 unsigned int size;
129 struct gpio_device *gdev;
130 unsigned long *get_mask;
131 unsigned long *set_mask;
132 unsigned long invert_mask[];
133};
134
135#define for_each_gpio_desc(gc, desc) \
136 for (unsigned int __i = 0; \
137 __i < gc->ngpio && (desc = gpiochip_get_desc(gc, __i)); \
138 __i++) \
139
140#define for_each_gpio_desc_with_flag(gc, desc, flag) \
141 for_each_gpio_desc(gc, desc) \
142 if (!test_bit(flag, &desc->flags)) {} else
143
144int gpiod_get_array_value_complex(bool raw, bool can_sleep,
145 unsigned int array_size,
146 struct gpio_desc **desc_array,
147 struct gpio_array *array_info,
148 unsigned long *value_bitmap);
149int gpiod_set_array_value_complex(bool raw, bool can_sleep,
150 unsigned int array_size,
151 struct gpio_desc **desc_array,
152 struct gpio_array *array_info,
153 unsigned long *value_bitmap);
154
155int gpiod_set_transitory(struct gpio_desc *desc, bool transitory);
156
157void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action);
158int gpiod_direction_output_nonotify(struct gpio_desc *desc, int value);
159int gpiod_direction_input_nonotify(struct gpio_desc *desc);
160
161struct gpio_desc_label {
162 struct rcu_head rh;
163 char str[];
164};
165
166/**
167 * struct gpio_desc - Opaque descriptor for a GPIO
168 *
169 * @gdev: Pointer to the parent GPIO device
170 * @flags: Binary descriptor flags
171 * @label: Name of the consumer
172 * @name: Line name
173 * @hog: Pointer to the device node that hogs this line (if any)
174 * @debounce_period_us: Debounce period in microseconds
175 *
176 * These are obtained using gpiod_get() and are preferable to the old
177 * integer-based handles.
178 *
179 * Contrary to integers, a pointer to a &struct gpio_desc is guaranteed to be
180 * valid until the GPIO is released.
181 */
182struct gpio_desc {
183 struct gpio_device *gdev;
184 unsigned long flags;
185/* flag symbols are bit numbers */
186#define FLAG_REQUESTED 0
187#define FLAG_IS_OUT 1
188#define FLAG_EXPORT 2 /* protected by sysfs_lock */
189#define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */
190#define FLAG_ACTIVE_LOW 6 /* value has active low */
191#define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */
192#define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */
193#define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */
194#define FLAG_IRQ_IS_ENABLED 10 /* GPIO is connected to an enabled IRQ */
195#define FLAG_IS_HOGGED 11 /* GPIO is hogged */
196#define FLAG_TRANSITORY 12 /* GPIO may lose value in sleep or reset */
197#define FLAG_PULL_UP 13 /* GPIO has pull up enabled */
198#define FLAG_PULL_DOWN 14 /* GPIO has pull down enabled */
199#define FLAG_BIAS_DISABLE 15 /* GPIO has pull disabled */
200#define FLAG_EDGE_RISING 16 /* GPIO CDEV detects rising edge events */
201#define FLAG_EDGE_FALLING 17 /* GPIO CDEV detects falling edge events */
202#define FLAG_EVENT_CLOCK_REALTIME 18 /* GPIO CDEV reports REALTIME timestamps in events */
203#define FLAG_EVENT_CLOCK_HTE 19 /* GPIO CDEV reports hardware timestamps in events */
204
205 /* Connection label */
206 struct gpio_desc_label __rcu *label;
207 /* Name of the GPIO */
208 const char *name;
209#ifdef CONFIG_OF_DYNAMIC
210 struct device_node *hog;
211#endif
212#ifdef CONFIG_GPIO_CDEV
213 /* debounce period in microseconds */
214 unsigned int debounce_period_us;
215#endif
216};
217
218#define gpiod_not_found(desc) (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT)
219
220struct gpio_chip_guard {
221 struct gpio_device *gdev;
222 struct gpio_chip *gc;
223 int idx;
224};
225
226DEFINE_CLASS(gpio_chip_guard,
227 struct gpio_chip_guard,
228 srcu_read_unlock(&_T.gdev->srcu, _T.idx),
229 ({
230 struct gpio_chip_guard _guard;
231
232 _guard.gdev = desc->gdev;
233 _guard.idx = srcu_read_lock(&_guard.gdev->srcu);
234 _guard.gc = srcu_dereference(_guard.gdev->chip,
235 &_guard.gdev->srcu);
236
237 _guard;
238 }),
239 struct gpio_desc *desc)
240
241int gpiod_request(struct gpio_desc *desc, const char *label);
242void gpiod_free(struct gpio_desc *desc);
243
244static inline int gpiod_request_user(struct gpio_desc *desc, const char *label)
245{
246 int ret;
247
248 ret = gpiod_request(desc, label);
249 if (ret == -EPROBE_DEFER)
250 ret = -ENODEV;
251
252 return ret;
253}
254
255struct gpio_desc *gpiod_find_and_request(struct device *consumer,
256 struct fwnode_handle *fwnode,
257 const char *con_id,
258 unsigned int idx,
259 enum gpiod_flags flags,
260 const char *label,
261 bool platform_lookup_allowed);
262
263int gpio_do_set_config(struct gpio_desc *desc, unsigned long config);
264int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
265 unsigned long lflags, enum gpiod_flags dflags);
266int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce);
267int gpiod_hog(struct gpio_desc *desc, const char *name,
268 unsigned long lflags, enum gpiod_flags dflags);
269int gpiochip_get_ngpios(struct gpio_chip *gc, struct device *dev);
270struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc, unsigned int hwnum);
271const char *gpiod_get_label(struct gpio_desc *desc);
272
273/*
274 * Return the GPIO number of the passed descriptor relative to its chip
275 */
276static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
277{
278 return desc - &desc->gdev->descs[0];
279}
280
281/* With descriptor prefix */
282
283#define gpiod_err(desc, fmt, ...) \
284do { \
285 scoped_guard(srcu, &desc->gdev->desc_srcu) { \
286 pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), \
287 gpiod_get_label(desc) ? : "?", ##__VA_ARGS__); \
288 } \
289} while (0)
290
291#define gpiod_warn(desc, fmt, ...) \
292do { \
293 scoped_guard(srcu, &desc->gdev->desc_srcu) { \
294 pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), \
295 gpiod_get_label(desc) ? : "?", ##__VA_ARGS__); \
296 } \
297} while (0)
298
299#define gpiod_dbg(desc, fmt, ...) \
300do { \
301 scoped_guard(srcu, &desc->gdev->desc_srcu) { \
302 pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), \
303 gpiod_get_label(desc) ? : "?", ##__VA_ARGS__); \
304 } \
305} while (0)
306
307/* With chip prefix */
308
309#define chip_err(gc, fmt, ...) \
310 dev_err(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
311#define chip_warn(gc, fmt, ...) \
312 dev_warn(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
313#define chip_info(gc, fmt, ...) \
314 dev_info(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
315#define chip_dbg(gc, fmt, ...) \
316 dev_dbg(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
317
318#endif /* GPIOLIB_H */