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 */
46 struct 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 */
73 static __maybe_unused const char * const gpio_suffixes[] = { "gpios", "gpio" };
74
75 struct 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
84 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc, unsigned int hwnum);
85 int 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);
90 int 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
96 extern spinlock_t gpio_lock;
97 extern struct list_head gpio_devices;
98
99 struct 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 #define FLAG_EDGE_RISING 16 /* GPIO CDEV detects rising edge events */
118 #define FLAG_EDGE_FALLING 17 /* GPIO CDEV detects falling edge events */
119
120 /* Connection label */
121 const char *label;
122 /* Name of the GPIO */
123 const char *name;
124 #ifdef CONFIG_OF_DYNAMIC
125 struct device_node *hog;
126 #endif
127 #ifdef CONFIG_GPIO_CDEV
128 /* debounce period in microseconds */
129 unsigned int debounce_period_us;
130 #endif
131 };
132
133 int gpiod_request(struct gpio_desc *desc, const char *label);
134 void gpiod_free(struct gpio_desc *desc);
135 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
136 unsigned long lflags, enum gpiod_flags dflags);
137 int gpiod_hog(struct gpio_desc *desc, const char *name,
138 unsigned long lflags, enum gpiod_flags dflags);
139
140 /*
141 * Return the GPIO number of the passed descriptor relative to its chip
142 */
gpio_chip_hwgpio(const struct gpio_desc * desc)143 static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
144 {
145 return desc - &desc->gdev->descs[0];
146 }
147
148 /* With descriptor prefix */
149
150 #define gpiod_emerg(desc, fmt, ...) \
151 pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
152 ##__VA_ARGS__)
153 #define gpiod_crit(desc, fmt, ...) \
154 pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
155 ##__VA_ARGS__)
156 #define gpiod_err(desc, fmt, ...) \
157 pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
158 ##__VA_ARGS__)
159 #define gpiod_warn(desc, fmt, ...) \
160 pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
161 ##__VA_ARGS__)
162 #define gpiod_info(desc, fmt, ...) \
163 pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
164 ##__VA_ARGS__)
165 #define gpiod_dbg(desc, fmt, ...) \
166 pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
167 ##__VA_ARGS__)
168
169 /* With chip prefix */
170
171 #define chip_emerg(gc, fmt, ...) \
172 dev_emerg(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
173 #define chip_crit(gc, fmt, ...) \
174 dev_crit(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
175 #define chip_err(gc, fmt, ...) \
176 dev_err(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
177 #define chip_warn(gc, fmt, ...) \
178 dev_warn(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
179 #define chip_info(gc, fmt, ...) \
180 dev_info(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
181 #define chip_dbg(gc, fmt, ...) \
182 dev_dbg(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
183
184 #endif /* GPIOLIB_H */
185