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