xref: /openbmc/linux/drivers/gpio/gpiolib.h (revision 4cff79e9)
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/gpio/consumer.h> /* for enum gpiod_flags */
17 #include <linux/err.h>
18 #include <linux/device.h>
19 #include <linux/module.h>
20 #include <linux/cdev.h>
21 
22 enum of_gpio_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 	const 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  * @adev: reference to ACPI device which consumes GPIO resource
79  * @flags: GPIO initialization flags
80  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
81  * @polarity: interrupt polarity as provided by ACPI
82  * @triggering: triggering type as provided by ACPI
83  * @quirks: Linux specific quirks as provided by struct acpi_gpio_mapping
84  */
85 struct acpi_gpio_info {
86 	struct acpi_device *adev;
87 	enum gpiod_flags flags;
88 	bool gpioint;
89 	int polarity;
90 	int triggering;
91 	unsigned int quirks;
92 };
93 
94 /* gpio suffixes used for ACPI and device tree lookup */
95 static const char * const gpio_suffixes[] = { "gpios", "gpio" };
96 
97 #ifdef CONFIG_OF_GPIO
98 struct gpio_desc *of_find_gpio(struct device *dev,
99 			       const char *con_id,
100 			       unsigned int idx,
101 			       enum gpio_lookup_flags *flags);
102 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
103 		   const char *list_name, int index, enum of_gpio_flags *flags);
104 int of_gpiochip_add(struct gpio_chip *gc);
105 void of_gpiochip_remove(struct gpio_chip *gc);
106 #else
107 static inline struct gpio_desc *of_find_gpio(struct device *dev,
108 					     const char *con_id,
109 					     unsigned int idx,
110 					     enum gpio_lookup_flags *flags)
111 {
112 	return ERR_PTR(-ENOENT);
113 }
114 static inline struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
115 		   const char *list_name, int index, enum of_gpio_flags *flags)
116 {
117 	return ERR_PTR(-ENOENT);
118 }
119 static inline int of_gpiochip_add(struct gpio_chip *gc) { return 0; }
120 static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
121 #endif /* CONFIG_OF_GPIO */
122 
123 #ifdef CONFIG_ACPI
124 void acpi_gpiochip_add(struct gpio_chip *chip);
125 void acpi_gpiochip_remove(struct gpio_chip *chip);
126 
127 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
128 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
129 
130 int acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags,
131 				 struct acpi_gpio_info *info);
132 
133 struct gpio_desc *acpi_find_gpio(struct device *dev,
134 				 const char *con_id,
135 				 unsigned int idx,
136 				 enum gpiod_flags *dflags,
137 				 enum gpio_lookup_flags *lookupflags);
138 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
139 				      const char *propname, int index,
140 				      struct acpi_gpio_info *info);
141 
142 int acpi_gpio_count(struct device *dev, const char *con_id);
143 
144 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id);
145 #else
146 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
147 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
148 
149 static inline void
150 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
151 
152 static inline void
153 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
154 
155 static inline int
156 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
157 {
158 	return 0;
159 }
160 
161 static inline struct gpio_desc *
162 acpi_find_gpio(struct device *dev, const char *con_id,
163 	       unsigned int idx, enum gpiod_flags *dflags,
164 	       enum gpio_lookup_flags *lookupflags)
165 {
166 	return ERR_PTR(-ENOENT);
167 }
168 static inline struct gpio_desc *
169 acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
170 		    int index, struct acpi_gpio_info *info)
171 {
172 	return ERR_PTR(-ENXIO);
173 }
174 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
175 {
176 	return -ENODEV;
177 }
178 
179 static inline bool acpi_can_fallback_to_crs(struct acpi_device *adev,
180 					    const char *con_id)
181 {
182 	return false;
183 }
184 #endif
185 
186 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
187 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
188 				  unsigned int array_size,
189 				  struct gpio_desc **desc_array,
190 				  int *value_array);
191 void gpiod_set_array_value_complex(bool raw, bool can_sleep,
192 				   unsigned int array_size,
193 				   struct gpio_desc **desc_array,
194 				   int *value_array);
195 
196 /* This is just passed between gpiolib and devres */
197 struct gpio_desc *gpiod_get_from_of_node(struct device_node *node,
198 					 const char *propname, int index,
199 					 enum gpiod_flags dflags,
200 					 const char *label);
201 
202 extern struct spinlock gpio_lock;
203 extern struct list_head gpio_devices;
204 
205 struct gpio_desc {
206 	struct gpio_device	*gdev;
207 	unsigned long		flags;
208 /* flag symbols are bit numbers */
209 #define FLAG_REQUESTED	0
210 #define FLAG_IS_OUT	1
211 #define FLAG_EXPORT	2	/* protected by sysfs_lock */
212 #define FLAG_SYSFS	3	/* exported via /sys/class/gpio/control */
213 #define FLAG_ACTIVE_LOW	6	/* value has active low */
214 #define FLAG_OPEN_DRAIN	7	/* Gpio is open drain type */
215 #define FLAG_OPEN_SOURCE 8	/* Gpio is open source type */
216 #define FLAG_USED_AS_IRQ 9	/* GPIO is connected to an IRQ */
217 #define FLAG_IS_HOGGED	11	/* GPIO is hogged */
218 #define FLAG_TRANSITORY 12	/* GPIO may lose value in sleep or reset */
219 
220 	/* Connection label */
221 	const char		*label;
222 	/* Name of the GPIO */
223 	const char		*name;
224 };
225 
226 int gpiod_request(struct gpio_desc *desc, const char *label);
227 void gpiod_free(struct gpio_desc *desc);
228 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
229 		unsigned long lflags, enum gpiod_flags dflags);
230 int gpiod_hog(struct gpio_desc *desc, const char *name,
231 		unsigned long lflags, enum gpiod_flags dflags);
232 
233 /*
234  * Return the GPIO number of the passed descriptor relative to its chip
235  */
236 static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
237 {
238 	return desc - &desc->gdev->descs[0];
239 }
240 
241 void devprop_gpiochip_set_names(struct gpio_chip *chip,
242 				const struct fwnode_handle *fwnode);
243 
244 /* With descriptor prefix */
245 
246 #define gpiod_emerg(desc, fmt, ...)					       \
247 	pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
248 		 ##__VA_ARGS__)
249 #define gpiod_crit(desc, fmt, ...)					       \
250 	pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
251 		 ##__VA_ARGS__)
252 #define gpiod_err(desc, fmt, ...)					       \
253 	pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
254 		 ##__VA_ARGS__)
255 #define gpiod_warn(desc, fmt, ...)					       \
256 	pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
257 		 ##__VA_ARGS__)
258 #define gpiod_info(desc, fmt, ...)					       \
259 	pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
260 		 ##__VA_ARGS__)
261 #define gpiod_dbg(desc, fmt, ...)					       \
262 	pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
263 		 ##__VA_ARGS__)
264 
265 /* With chip prefix */
266 
267 #define chip_emerg(chip, fmt, ...)					\
268 	dev_emerg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
269 #define chip_crit(chip, fmt, ...)					\
270 	dev_crit(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
271 #define chip_err(chip, fmt, ...)					\
272 	dev_err(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
273 #define chip_warn(chip, fmt, ...)					\
274 	dev_warn(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
275 #define chip_info(chip, fmt, ...)					\
276 	dev_info(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
277 #define chip_dbg(chip, fmt, ...)					\
278 	dev_dbg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
279 
280 #ifdef CONFIG_GPIO_SYSFS
281 
282 int gpiochip_sysfs_register(struct gpio_device *gdev);
283 void gpiochip_sysfs_unregister(struct gpio_device *gdev);
284 
285 #else
286 
287 static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
288 {
289 	return 0;
290 }
291 
292 static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
293 {
294 }
295 
296 #endif /* CONFIG_GPIO_SYSFS */
297 
298 #endif /* GPIOLIB_H */
299