xref: /openbmc/linux/drivers/gpio/gpiolib.h (revision 6c33a6f4)
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 
60 #ifdef CONFIG_PINCTRL
61 	/*
62 	 * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
63 	 * describe the actual pin range which they serve in an SoC. This
64 	 * information would be used by pinctrl subsystem to configure
65 	 * corresponding pins for gpio usage.
66 	 */
67 	struct list_head pin_ranges;
68 #endif
69 };
70 
71 /* gpio suffixes used for ACPI and device tree lookup */
72 static __maybe_unused const char * const gpio_suffixes[] = { "gpios", "gpio" };
73 
74 struct gpio_array {
75 	struct gpio_desc	**desc;
76 	unsigned int		size;
77 	struct gpio_chip	*chip;
78 	unsigned long		*get_mask;
79 	unsigned long		*set_mask;
80 	unsigned long		invert_mask[];
81 };
82 
83 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
84 				    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 
118 	/* Connection label */
119 	const char		*label;
120 	/* Name of the GPIO */
121 	const char		*name;
122 };
123 
124 int gpiod_request(struct gpio_desc *desc, const char *label);
125 void gpiod_free(struct gpio_desc *desc);
126 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
127 		unsigned long lflags, enum gpiod_flags dflags);
128 int gpiod_hog(struct gpio_desc *desc, const char *name,
129 		unsigned long lflags, enum gpiod_flags dflags);
130 
131 /*
132  * Return the GPIO number of the passed descriptor relative to its chip
133  */
134 static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
135 {
136 	return desc - &desc->gdev->descs[0];
137 }
138 
139 /* With descriptor prefix */
140 
141 #define gpiod_emerg(desc, fmt, ...)					       \
142 	pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
143 		 ##__VA_ARGS__)
144 #define gpiod_crit(desc, fmt, ...)					       \
145 	pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
146 		 ##__VA_ARGS__)
147 #define gpiod_err(desc, fmt, ...)					       \
148 	pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
149 		 ##__VA_ARGS__)
150 #define gpiod_warn(desc, fmt, ...)					       \
151 	pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
152 		 ##__VA_ARGS__)
153 #define gpiod_info(desc, fmt, ...)					       \
154 	pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
155 		 ##__VA_ARGS__)
156 #define gpiod_dbg(desc, fmt, ...)					       \
157 	pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
158 		 ##__VA_ARGS__)
159 
160 /* With chip prefix */
161 
162 #define chip_emerg(chip, fmt, ...)					\
163 	dev_emerg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
164 #define chip_crit(chip, fmt, ...)					\
165 	dev_crit(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
166 #define chip_err(chip, fmt, ...)					\
167 	dev_err(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
168 #define chip_warn(chip, fmt, ...)					\
169 	dev_warn(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
170 #define chip_info(chip, fmt, ...)					\
171 	dev_info(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
172 #define chip_dbg(chip, fmt, ...)					\
173 	dev_dbg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
174 
175 #ifdef CONFIG_GPIO_SYSFS
176 
177 int gpiochip_sysfs_register(struct gpio_device *gdev);
178 void gpiochip_sysfs_unregister(struct gpio_device *gdev);
179 
180 #else
181 
182 static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
183 {
184 	return 0;
185 }
186 
187 static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
188 {
189 }
190 
191 #endif /* CONFIG_GPIO_SYSFS */
192 
193 #endif /* GPIOLIB_H */
194