xref: /openbmc/linux/drivers/gpio/gpiolib.h (revision 239480ab)
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  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
79  * @polarity: interrupt polarity as provided by ACPI
80  * @triggering: triggering type as provided by ACPI
81  */
82 struct acpi_gpio_info {
83 	bool gpioint;
84 	int polarity;
85 	int triggering;
86 };
87 
88 /* gpio suffixes used for ACPI and device tree lookup */
89 static const char * const gpio_suffixes[] = { "gpios", "gpio" };
90 
91 #ifdef CONFIG_OF_GPIO
92 struct gpio_desc *of_find_gpio(struct device *dev,
93 			       const char *con_id,
94 			       unsigned int idx,
95 			       enum gpio_lookup_flags *flags);
96 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
97 		   const char *list_name, int index, enum of_gpio_flags *flags);
98 int of_gpiochip_add(struct gpio_chip *gc);
99 void of_gpiochip_remove(struct gpio_chip *gc);
100 #else
101 static inline struct gpio_desc *of_find_gpio(struct device *dev,
102 					     const char *con_id,
103 					     unsigned int idx,
104 					     enum gpio_lookup_flags *flags)
105 {
106 	return ERR_PTR(-ENOENT);
107 }
108 static inline struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
109 		   const char *list_name, int index, enum of_gpio_flags *flags)
110 {
111 	return ERR_PTR(-ENOENT);
112 }
113 static inline int of_gpiochip_add(struct gpio_chip *gc) { return 0; }
114 static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
115 #endif /* CONFIG_OF_GPIO */
116 
117 #ifdef CONFIG_ACPI
118 void acpi_gpiochip_add(struct gpio_chip *chip);
119 void acpi_gpiochip_remove(struct gpio_chip *chip);
120 
121 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
122 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
123 
124 struct gpio_desc *acpi_find_gpio(struct device *dev,
125 				 const char *con_id,
126 				 unsigned int idx,
127 				 enum gpiod_flags flags,
128 				 enum gpio_lookup_flags *lookupflags);
129 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
130 				      const char *propname, int index,
131 				      struct acpi_gpio_info *info);
132 
133 int acpi_gpio_count(struct device *dev, const char *con_id);
134 
135 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id);
136 #else
137 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
138 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
139 
140 static inline void
141 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
142 
143 static inline void
144 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
145 
146 static inline struct gpio_desc *
147 acpi_find_gpio(struct device *dev, const char *con_id,
148 	       unsigned int idx, enum gpiod_flags flags,
149 	       enum gpio_lookup_flags *lookupflags)
150 {
151 	return ERR_PTR(-ENOENT);
152 }
153 static inline struct gpio_desc *
154 acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
155 		    int index, struct acpi_gpio_info *info)
156 {
157 	return ERR_PTR(-ENXIO);
158 }
159 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
160 {
161 	return -ENODEV;
162 }
163 
164 static inline bool acpi_can_fallback_to_crs(struct acpi_device *adev,
165 					    const char *con_id)
166 {
167 	return false;
168 }
169 #endif
170 
171 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
172 void gpiod_set_array_value_complex(bool raw, bool can_sleep,
173 				   unsigned int array_size,
174 				   struct gpio_desc **desc_array,
175 				   int *value_array);
176 
177 extern struct spinlock gpio_lock;
178 extern struct list_head gpio_devices;
179 
180 struct gpio_desc {
181 	struct gpio_device	*gdev;
182 	unsigned long		flags;
183 /* flag symbols are bit numbers */
184 #define FLAG_REQUESTED	0
185 #define FLAG_IS_OUT	1
186 #define FLAG_EXPORT	2	/* protected by sysfs_lock */
187 #define FLAG_SYSFS	3	/* exported via /sys/class/gpio/control */
188 #define FLAG_ACTIVE_LOW	6	/* value has active low */
189 #define FLAG_OPEN_DRAIN	7	/* Gpio is open drain type */
190 #define FLAG_OPEN_SOURCE 8	/* Gpio is open source type */
191 #define FLAG_USED_AS_IRQ 9	/* GPIO is connected to an IRQ */
192 #define FLAG_IS_HOGGED	11	/* GPIO is hogged */
193 
194 	/* Connection label */
195 	const char		*label;
196 	/* Name of the GPIO */
197 	const char		*name;
198 };
199 
200 int gpiod_request(struct gpio_desc *desc, const char *label);
201 void gpiod_free(struct gpio_desc *desc);
202 int gpiod_hog(struct gpio_desc *desc, const char *name,
203 		unsigned long lflags, enum gpiod_flags dflags);
204 
205 /*
206  * Return the GPIO number of the passed descriptor relative to its chip
207  */
208 static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
209 {
210 	return desc - &desc->gdev->descs[0];
211 }
212 
213 void devprop_gpiochip_set_names(struct gpio_chip *chip);
214 
215 /* With descriptor prefix */
216 
217 #define gpiod_emerg(desc, fmt, ...)					       \
218 	pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
219 		 ##__VA_ARGS__)
220 #define gpiod_crit(desc, fmt, ...)					       \
221 	pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
222 		 ##__VA_ARGS__)
223 #define gpiod_err(desc, fmt, ...)					       \
224 	pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
225 		 ##__VA_ARGS__)
226 #define gpiod_warn(desc, fmt, ...)					       \
227 	pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
228 		 ##__VA_ARGS__)
229 #define gpiod_info(desc, fmt, ...)					       \
230 	pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
231 		 ##__VA_ARGS__)
232 #define gpiod_dbg(desc, fmt, ...)					       \
233 	pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
234 		 ##__VA_ARGS__)
235 
236 /* With chip prefix */
237 
238 #define chip_emerg(chip, fmt, ...)					\
239 	dev_emerg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
240 #define chip_crit(chip, fmt, ...)					\
241 	dev_crit(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
242 #define chip_err(chip, fmt, ...)					\
243 	dev_err(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
244 #define chip_warn(chip, fmt, ...)					\
245 	dev_warn(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
246 #define chip_info(chip, fmt, ...)					\
247 	dev_info(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
248 #define chip_dbg(chip, fmt, ...)					\
249 	dev_dbg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
250 
251 #ifdef CONFIG_GPIO_SYSFS
252 
253 int gpiochip_sysfs_register(struct gpio_device *gdev);
254 void gpiochip_sysfs_unregister(struct gpio_device *gdev);
255 
256 #else
257 
258 static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
259 {
260 	return 0;
261 }
262 
263 static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
264 {
265 }
266 
267 #endif /* CONFIG_GPIO_SYSFS */
268 
269 #endif /* GPIOLIB_H */
270