xref: /openbmc/linux/drivers/gpio/gpiolib.h (revision c1d3fb8a)
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 /**
20  * struct gpio_device - internal state container for GPIO devices
21  * @id: numerical ID number for the GPIO chip
22  * @dev: the GPIO device struct
23  * @chrdev: character device for the GPIO device
24  * @mockdev: class device used by the deprecated sysfs interface (may be
25  * NULL)
26  * @owner: helps prevent removal of modules exporting active GPIOs
27  * @chip: pointer to the corresponding gpiochip, holding static
28  * data for this device
29  * @descs: array of ngpio descriptors.
30  * @ngpio: the number of GPIO lines on this GPIO device, equal to the size
31  * of the @descs array.
32  * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned
33  * at device creation time.
34  * @label: a descriptive name for the GPIO device, such as the part number
35  * or name of the IP component in a System on Chip.
36  * @data: per-instance data assigned by the driver
37  * @list: links gpio_device:s together for traversal
38  *
39  * This state container holds most of the runtime variable data
40  * for a GPIO device and can hold references and live on after the
41  * GPIO chip has been removed, if it is still being used from
42  * userspace.
43  */
44 struct gpio_device {
45 	int			id;
46 	struct device		dev;
47 	struct cdev		chrdev;
48 	struct device		*mockdev;
49 	struct module		*owner;
50 	struct gpio_chip	*chip;
51 	struct gpio_desc	*descs;
52 	int			base;
53 	u16			ngpio;
54 	const char		*label;
55 	void			*data;
56 	struct list_head        list;
57 
58 #ifdef CONFIG_PINCTRL
59 	/*
60 	 * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
61 	 * describe the actual pin range which they serve in an SoC. This
62 	 * information would be used by pinctrl subsystem to configure
63 	 * corresponding pins for gpio usage.
64 	 */
65 	struct list_head pin_ranges;
66 #endif
67 };
68 
69 /* gpio suffixes used for ACPI and device tree lookup */
70 static __maybe_unused const char * const gpio_suffixes[] = { "gpios", "gpio" };
71 
72 struct gpio_array {
73 	struct gpio_desc	**desc;
74 	unsigned int		size;
75 	struct gpio_chip	*chip;
76 	unsigned long		*get_mask;
77 	unsigned long		*set_mask;
78 	unsigned long		invert_mask[];
79 };
80 
81 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
82 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
83 				  unsigned int array_size,
84 				  struct gpio_desc **desc_array,
85 				  struct gpio_array *array_info,
86 				  unsigned long *value_bitmap);
87 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
88 				  unsigned int array_size,
89 				  struct gpio_desc **desc_array,
90 				  struct gpio_array *array_info,
91 				  unsigned long *value_bitmap);
92 
93 extern spinlock_t gpio_lock;
94 extern struct list_head gpio_devices;
95 
96 struct gpio_desc {
97 	struct gpio_device	*gdev;
98 	unsigned long		flags;
99 /* flag symbols are bit numbers */
100 #define FLAG_REQUESTED	0
101 #define FLAG_IS_OUT	1
102 #define FLAG_EXPORT	2	/* protected by sysfs_lock */
103 #define FLAG_SYSFS	3	/* exported via /sys/class/gpio/control */
104 #define FLAG_ACTIVE_LOW	6	/* value has active low */
105 #define FLAG_OPEN_DRAIN	7	/* Gpio is open drain type */
106 #define FLAG_OPEN_SOURCE 8	/* Gpio is open source type */
107 #define FLAG_USED_AS_IRQ 9	/* GPIO is connected to an IRQ */
108 #define FLAG_IRQ_IS_ENABLED 10	/* GPIO is connected to an enabled IRQ */
109 #define FLAG_IS_HOGGED	11	/* GPIO is hogged */
110 #define FLAG_TRANSITORY 12	/* GPIO may lose value in sleep or reset */
111 #define FLAG_PULL_UP    13	/* GPIO has pull up enabled */
112 #define FLAG_PULL_DOWN  14	/* GPIO has pull down enabled */
113 #define FLAG_BIAS_DISABLE    15	/* GPIO has pull disabled */
114 
115 	/* Connection label */
116 	const char		*label;
117 	/* Name of the GPIO */
118 	const char		*name;
119 };
120 
121 int gpiod_request(struct gpio_desc *desc, const char *label);
122 void gpiod_free(struct gpio_desc *desc);
123 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
124 		unsigned long lflags, enum gpiod_flags dflags);
125 int gpiod_hog(struct gpio_desc *desc, const char *name,
126 		unsigned long lflags, enum gpiod_flags dflags);
127 
128 /*
129  * Return the GPIO number of the passed descriptor relative to its chip
130  */
131 static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
132 {
133 	return desc - &desc->gdev->descs[0];
134 }
135 
136 /* With descriptor prefix */
137 
138 #define gpiod_emerg(desc, fmt, ...)					       \
139 	pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
140 		 ##__VA_ARGS__)
141 #define gpiod_crit(desc, fmt, ...)					       \
142 	pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
143 		 ##__VA_ARGS__)
144 #define gpiod_err(desc, fmt, ...)					       \
145 	pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
146 		 ##__VA_ARGS__)
147 #define gpiod_warn(desc, fmt, ...)					       \
148 	pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
149 		 ##__VA_ARGS__)
150 #define gpiod_info(desc, fmt, ...)					       \
151 	pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
152 		 ##__VA_ARGS__)
153 #define gpiod_dbg(desc, fmt, ...)					       \
154 	pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
155 		 ##__VA_ARGS__)
156 
157 /* With chip prefix */
158 
159 #define chip_emerg(chip, fmt, ...)					\
160 	dev_emerg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
161 #define chip_crit(chip, fmt, ...)					\
162 	dev_crit(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
163 #define chip_err(chip, fmt, ...)					\
164 	dev_err(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
165 #define chip_warn(chip, fmt, ...)					\
166 	dev_warn(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
167 #define chip_info(chip, fmt, ...)					\
168 	dev_info(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
169 #define chip_dbg(chip, fmt, ...)					\
170 	dev_dbg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
171 
172 #ifdef CONFIG_GPIO_SYSFS
173 
174 int gpiochip_sysfs_register(struct gpio_device *gdev);
175 void gpiochip_sysfs_unregister(struct gpio_device *gdev);
176 
177 #else
178 
179 static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
180 {
181 	return 0;
182 }
183 
184 static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
185 {
186 }
187 
188 #endif /* CONFIG_GPIO_SYSFS */
189 
190 #endif /* GPIOLIB_H */
191