xref: /linux/drivers/gpio/gpiolib.h (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
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 
21 enum of_gpio_flags;
22 enum gpiod_flags;
23 enum gpio_lookup_flags;
24 struct acpi_device;
25 
26 /**
27  * struct gpio_device - internal state container for GPIO devices
28  * @id: numerical ID number for the GPIO chip
29  * @dev: the GPIO device struct
30  * @chrdev: character device for the GPIO device
31  * @mockdev: class device used by the deprecated sysfs interface (may be
32  * NULL)
33  * @owner: helps prevent removal of modules exporting active GPIOs
34  * @chip: pointer to the corresponding gpiochip, holding static
35  * data for this device
36  * @descs: array of ngpio descriptors.
37  * @ngpio: the number of GPIO lines on this GPIO device, equal to the size
38  * of the @descs array.
39  * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned
40  * at device creation time.
41  * @label: a descriptive name for the GPIO device, such as the part number
42  * or name of the IP component in a System on Chip.
43  * @data: per-instance data assigned by the driver
44  * @list: links gpio_device:s together for traversal
45  *
46  * This state container holds most of the runtime variable data
47  * for a GPIO device and can hold references and live on after the
48  * GPIO chip has been removed, if it is still being used from
49  * userspace.
50  */
51 struct gpio_device {
52 	int			id;
53 	struct device		dev;
54 	struct cdev		chrdev;
55 	struct device		*mockdev;
56 	struct module		*owner;
57 	struct gpio_chip	*chip;
58 	struct gpio_desc	*descs;
59 	int			base;
60 	u16			ngpio;
61 	char			*label;
62 	void			*data;
63 	struct list_head        list;
64 
65 #ifdef CONFIG_PINCTRL
66 	/*
67 	 * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
68 	 * describe the actual pin range which they serve in an SoC. This
69 	 * information would be used by pinctrl subsystem to configure
70 	 * corresponding pins for gpio usage.
71 	 */
72 	struct list_head pin_ranges;
73 #endif
74 };
75 
76 /**
77  * struct acpi_gpio_info - ACPI GPIO specific information
78  * @flags: GPIO initialization flags
79  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
80  * @polarity: interrupt polarity as provided by ACPI
81  * @triggering: triggering type as provided by ACPI
82  */
83 struct acpi_gpio_info {
84 	enum gpiod_flags flags;
85 	bool gpioint;
86 	int polarity;
87 	int triggering;
88 };
89 
90 /* gpio suffixes used for ACPI and device tree lookup */
91 static const char * const gpio_suffixes[] = { "gpios", "gpio" };
92 
93 #ifdef CONFIG_OF_GPIO
94 struct gpio_desc *of_find_gpio(struct device *dev,
95 			       const char *con_id,
96 			       unsigned int idx,
97 			       enum gpio_lookup_flags *flags);
98 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
99 		   const char *list_name, int index, enum of_gpio_flags *flags);
100 int of_gpiochip_add(struct gpio_chip *gc);
101 void of_gpiochip_remove(struct gpio_chip *gc);
102 #else
103 static inline struct gpio_desc *of_find_gpio(struct device *dev,
104 					     const char *con_id,
105 					     unsigned int idx,
106 					     enum gpio_lookup_flags *flags)
107 {
108 	return ERR_PTR(-ENOENT);
109 }
110 static inline struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
111 		   const char *list_name, int index, enum of_gpio_flags *flags)
112 {
113 	return ERR_PTR(-ENOENT);
114 }
115 static inline int of_gpiochip_add(struct gpio_chip *gc) { return 0; }
116 static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
117 #endif /* CONFIG_OF_GPIO */
118 
119 #ifdef CONFIG_ACPI
120 void acpi_gpiochip_add(struct gpio_chip *chip);
121 void acpi_gpiochip_remove(struct gpio_chip *chip);
122 
123 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
124 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
125 
126 int acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags,
127 				 enum gpiod_flags update);
128 
129 struct gpio_desc *acpi_find_gpio(struct device *dev,
130 				 const char *con_id,
131 				 unsigned int idx,
132 				 enum gpiod_flags *dflags,
133 				 enum gpio_lookup_flags *lookupflags);
134 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
135 				      const char *propname, int index,
136 				      struct acpi_gpio_info *info);
137 
138 int acpi_gpio_count(struct device *dev, const char *con_id);
139 
140 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id);
141 #else
142 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
143 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
144 
145 static inline void
146 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
147 
148 static inline void
149 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
150 
151 static inline int
152 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
153 {
154 	return 0;
155 }
156 
157 static inline struct gpio_desc *
158 acpi_find_gpio(struct device *dev, const char *con_id,
159 	       unsigned int idx, enum gpiod_flags *dflags,
160 	       enum gpio_lookup_flags *lookupflags)
161 {
162 	return ERR_PTR(-ENOENT);
163 }
164 static inline struct gpio_desc *
165 acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
166 		    int index, struct acpi_gpio_info *info)
167 {
168 	return ERR_PTR(-ENXIO);
169 }
170 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
171 {
172 	return -ENODEV;
173 }
174 
175 static inline bool acpi_can_fallback_to_crs(struct acpi_device *adev,
176 					    const char *con_id)
177 {
178 	return false;
179 }
180 #endif
181 
182 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
183 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
184 				  unsigned int array_size,
185 				  struct gpio_desc **desc_array,
186 				  int *value_array);
187 void gpiod_set_array_value_complex(bool raw, bool can_sleep,
188 				   unsigned int array_size,
189 				   struct gpio_desc **desc_array,
190 				   int *value_array);
191 
192 extern struct spinlock gpio_lock;
193 extern struct list_head gpio_devices;
194 
195 struct gpio_desc {
196 	struct gpio_device	*gdev;
197 	unsigned long		flags;
198 /* flag symbols are bit numbers */
199 #define FLAG_REQUESTED	0
200 #define FLAG_IS_OUT	1
201 #define FLAG_EXPORT	2	/* protected by sysfs_lock */
202 #define FLAG_SYSFS	3	/* exported via /sys/class/gpio/control */
203 #define FLAG_ACTIVE_LOW	6	/* value has active low */
204 #define FLAG_OPEN_DRAIN	7	/* Gpio is open drain type */
205 #define FLAG_OPEN_SOURCE 8	/* Gpio is open source type */
206 #define FLAG_USED_AS_IRQ 9	/* GPIO is connected to an IRQ */
207 #define FLAG_IS_HOGGED	11	/* GPIO is hogged */
208 #define FLAG_SLEEP_MAY_LOSE_VALUE 12	/* GPIO may lose value in sleep */
209 
210 	/* Connection label */
211 	const char		*label;
212 	/* Name of the GPIO */
213 	const char		*name;
214 };
215 
216 int gpiod_request(struct gpio_desc *desc, const char *label);
217 void gpiod_free(struct gpio_desc *desc);
218 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
219 		unsigned long lflags, enum gpiod_flags dflags);
220 int gpiod_hog(struct gpio_desc *desc, const char *name,
221 		unsigned long lflags, enum gpiod_flags dflags);
222 
223 /*
224  * Return the GPIO number of the passed descriptor relative to its chip
225  */
226 static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
227 {
228 	return desc - &desc->gdev->descs[0];
229 }
230 
231 void devprop_gpiochip_set_names(struct gpio_chip *chip);
232 
233 /* With descriptor prefix */
234 
235 #define gpiod_emerg(desc, fmt, ...)					       \
236 	pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
237 		 ##__VA_ARGS__)
238 #define gpiod_crit(desc, fmt, ...)					       \
239 	pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
240 		 ##__VA_ARGS__)
241 #define gpiod_err(desc, fmt, ...)					       \
242 	pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
243 		 ##__VA_ARGS__)
244 #define gpiod_warn(desc, fmt, ...)					       \
245 	pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
246 		 ##__VA_ARGS__)
247 #define gpiod_info(desc, fmt, ...)					       \
248 	pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
249 		 ##__VA_ARGS__)
250 #define gpiod_dbg(desc, fmt, ...)					       \
251 	pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
252 		 ##__VA_ARGS__)
253 
254 /* With chip prefix */
255 
256 #define chip_emerg(chip, fmt, ...)					\
257 	dev_emerg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
258 #define chip_crit(chip, fmt, ...)					\
259 	dev_crit(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
260 #define chip_err(chip, fmt, ...)					\
261 	dev_err(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
262 #define chip_warn(chip, fmt, ...)					\
263 	dev_warn(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
264 #define chip_info(chip, fmt, ...)					\
265 	dev_info(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
266 #define chip_dbg(chip, fmt, ...)					\
267 	dev_dbg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
268 
269 #ifdef CONFIG_GPIO_SYSFS
270 
271 int gpiochip_sysfs_register(struct gpio_device *gdev);
272 void gpiochip_sysfs_unregister(struct gpio_device *gdev);
273 
274 #else
275 
276 static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
277 {
278 	return 0;
279 }
280 
281 static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
282 {
283 }
284 
285 #endif /* CONFIG_GPIO_SYSFS */
286 
287 #endif /* GPIOLIB_H */
288