xref: /openbmc/linux/drivers/gpio/gpiolib.h (revision 74a22e8f)
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 enum of_gpio_flags;
20 struct acpi_device;
21 
22 /**
23  * struct gpio_device - internal state container for GPIO devices
24  * @id: numerical ID number for the GPIO chip
25  * @dev: the GPIO device struct
26  * @chrdev: character device for the GPIO device
27  * @mockdev: class device used by the deprecated sysfs interface (may be
28  * NULL)
29  * @owner: helps prevent removal of modules exporting active GPIOs
30  * @chip: pointer to the corresponding gpiochip, holding static
31  * data for this device
32  * @descs: array of ngpio descriptors.
33  * @ngpio: the number of GPIO lines on this GPIO device, equal to the size
34  * of the @descs array.
35  * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned
36  * at device creation time.
37  * @label: a descriptive name for the GPIO device, such as the part number
38  * or name of the IP component in a System on Chip.
39  * @data: per-instance data assigned by the driver
40  * @list: links gpio_device:s together for traversal
41  *
42  * This state container holds most of the runtime variable data
43  * for a GPIO device and can hold references and live on after the
44  * GPIO chip has been removed, if it is still being used from
45  * userspace.
46  */
47 struct gpio_device {
48 	int			id;
49 	struct device		dev;
50 	struct cdev		chrdev;
51 	struct device		*mockdev;
52 	struct module		*owner;
53 	struct gpio_chip	*chip;
54 	struct gpio_desc	*descs;
55 	int			base;
56 	u16			ngpio;
57 	const char		*label;
58 	void			*data;
59 	struct list_head        list;
60 
61 #ifdef CONFIG_PINCTRL
62 	/*
63 	 * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
64 	 * describe the actual pin range which they serve in an SoC. This
65 	 * information would be used by pinctrl subsystem to configure
66 	 * corresponding pins for gpio usage.
67 	 */
68 	struct list_head pin_ranges;
69 #endif
70 };
71 
72 /**
73  * struct acpi_gpio_info - ACPI GPIO specific information
74  * @adev: reference to ACPI device which consumes GPIO resource
75  * @flags: GPIO initialization flags
76  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
77  * @pin_config: pin bias as provided by ACPI
78  * @polarity: interrupt polarity as provided by ACPI
79  * @triggering: triggering type as provided by ACPI
80  * @quirks: Linux specific quirks as provided by struct acpi_gpio_mapping
81  */
82 struct acpi_gpio_info {
83 	struct acpi_device *adev;
84 	enum gpiod_flags flags;
85 	bool gpioint;
86 	int pin_config;
87 	int polarity;
88 	int triggering;
89 	unsigned int quirks;
90 };
91 
92 /* gpio suffixes used for ACPI and device tree lookup */
93 static __maybe_unused const char * const gpio_suffixes[] = { "gpios", "gpio" };
94 
95 #ifdef CONFIG_OF_GPIO
96 struct gpio_desc *of_find_gpio(struct device *dev,
97 			       const char *con_id,
98 			       unsigned int idx,
99 			       unsigned long *lookupflags);
100 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
101 		   const char *list_name, int index, enum of_gpio_flags *flags);
102 int of_gpiochip_add(struct gpio_chip *gc);
103 void of_gpiochip_remove(struct gpio_chip *gc);
104 #else
105 static inline struct gpio_desc *of_find_gpio(struct device *dev,
106 					     const char *con_id,
107 					     unsigned int idx,
108 					     unsigned long *lookupflags)
109 {
110 	return ERR_PTR(-ENOENT);
111 }
112 static inline struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
113 		   const char *list_name, int index, enum of_gpio_flags *flags)
114 {
115 	return ERR_PTR(-ENOENT);
116 }
117 static inline int of_gpiochip_add(struct gpio_chip *gc) { return 0; }
118 static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
119 #endif /* CONFIG_OF_GPIO */
120 
121 #ifdef CONFIG_ACPI
122 void acpi_gpiochip_add(struct gpio_chip *chip);
123 void acpi_gpiochip_remove(struct gpio_chip *chip);
124 
125 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
126 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
127 
128 int acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags,
129 				 struct acpi_gpio_info *info);
130 int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
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 				 unsigned long *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 static inline int
161 acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
162 				    struct acpi_gpio_info *info)
163 {
164 	return 0;
165 }
166 
167 static inline struct gpio_desc *
168 acpi_find_gpio(struct device *dev, const char *con_id,
169 	       unsigned int idx, enum gpiod_flags *dflags,
170 	       unsigned long *lookupflags)
171 {
172 	return ERR_PTR(-ENOENT);
173 }
174 static inline struct gpio_desc *
175 acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
176 		    int index, struct acpi_gpio_info *info)
177 {
178 	return ERR_PTR(-ENXIO);
179 }
180 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
181 {
182 	return -ENODEV;
183 }
184 
185 static inline bool acpi_can_fallback_to_crs(struct acpi_device *adev,
186 					    const char *con_id)
187 {
188 	return false;
189 }
190 #endif
191 
192 struct gpio_array {
193 	struct gpio_desc	**desc;
194 	unsigned int		size;
195 	struct gpio_chip	*chip;
196 	unsigned long		*get_mask;
197 	unsigned long		*set_mask;
198 	unsigned long		invert_mask[];
199 };
200 
201 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
202 int gpiod_get_array_value_complex(bool raw, bool can_sleep,
203 				  unsigned int array_size,
204 				  struct gpio_desc **desc_array,
205 				  struct gpio_array *array_info,
206 				  unsigned long *value_bitmap);
207 int gpiod_set_array_value_complex(bool raw, bool can_sleep,
208 				  unsigned int array_size,
209 				  struct gpio_desc **desc_array,
210 				  struct gpio_array *array_info,
211 				  unsigned long *value_bitmap);
212 
213 extern struct spinlock gpio_lock;
214 extern struct list_head gpio_devices;
215 
216 struct gpio_desc {
217 	struct gpio_device	*gdev;
218 	unsigned long		flags;
219 /* flag symbols are bit numbers */
220 #define FLAG_REQUESTED	0
221 #define FLAG_IS_OUT	1
222 #define FLAG_EXPORT	2	/* protected by sysfs_lock */
223 #define FLAG_SYSFS	3	/* exported via /sys/class/gpio/control */
224 #define FLAG_ACTIVE_LOW	6	/* value has active low */
225 #define FLAG_OPEN_DRAIN	7	/* Gpio is open drain type */
226 #define FLAG_OPEN_SOURCE 8	/* Gpio is open source type */
227 #define FLAG_USED_AS_IRQ 9	/* GPIO is connected to an IRQ */
228 #define FLAG_IRQ_IS_ENABLED 10	/* GPIO is connected to an enabled IRQ */
229 #define FLAG_IS_HOGGED	11	/* GPIO is hogged */
230 #define FLAG_TRANSITORY 12	/* GPIO may lose value in sleep or reset */
231 #define FLAG_PULL_UP    13	/* GPIO has pull up enabled */
232 #define FLAG_PULL_DOWN  14	/* GPIO has pull down enabled */
233 
234 	/* Connection label */
235 	const char		*label;
236 	/* Name of the GPIO */
237 	const char		*name;
238 };
239 
240 int gpiod_request(struct gpio_desc *desc, const char *label);
241 void gpiod_free(struct gpio_desc *desc);
242 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
243 		unsigned long lflags, enum gpiod_flags dflags);
244 int gpiod_hog(struct gpio_desc *desc, const char *name,
245 		unsigned long lflags, enum gpiod_flags dflags);
246 
247 /*
248  * Return the GPIO number of the passed descriptor relative to its chip
249  */
250 static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
251 {
252 	return desc - &desc->gdev->descs[0];
253 }
254 
255 /* With descriptor prefix */
256 
257 #define gpiod_emerg(desc, fmt, ...)					       \
258 	pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
259 		 ##__VA_ARGS__)
260 #define gpiod_crit(desc, fmt, ...)					       \
261 	pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
262 		 ##__VA_ARGS__)
263 #define gpiod_err(desc, fmt, ...)					       \
264 	pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
265 		 ##__VA_ARGS__)
266 #define gpiod_warn(desc, fmt, ...)					       \
267 	pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
268 		 ##__VA_ARGS__)
269 #define gpiod_info(desc, fmt, ...)					       \
270 	pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
271 		 ##__VA_ARGS__)
272 #define gpiod_dbg(desc, fmt, ...)					       \
273 	pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
274 		 ##__VA_ARGS__)
275 
276 /* With chip prefix */
277 
278 #define chip_emerg(chip, fmt, ...)					\
279 	dev_emerg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
280 #define chip_crit(chip, fmt, ...)					\
281 	dev_crit(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
282 #define chip_err(chip, fmt, ...)					\
283 	dev_err(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
284 #define chip_warn(chip, fmt, ...)					\
285 	dev_warn(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
286 #define chip_info(chip, fmt, ...)					\
287 	dev_info(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
288 #define chip_dbg(chip, fmt, ...)					\
289 	dev_dbg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
290 
291 #ifdef CONFIG_GPIO_SYSFS
292 
293 int gpiochip_sysfs_register(struct gpio_device *gdev);
294 void gpiochip_sysfs_unregister(struct gpio_device *gdev);
295 
296 #else
297 
298 static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
299 {
300 	return 0;
301 }
302 
303 static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
304 {
305 }
306 
307 #endif /* CONFIG_GPIO_SYSFS */
308 
309 #endif /* GPIOLIB_H */
310