2 * Internal GPIO functions.
4 * Copyright (C) 2013, Intel Corporation
5 * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
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.
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>
26 * struct gpio_device - internal state container for GPIO devices
27 * @id: numerical ID number for the GPIO chip
28 * @dev: the GPIO device struct
29 * @chrdev: character device for the GPIO device
30 * @owner: helps prevent removal of modules exporting active GPIOs
31 * @chip: pointer to the corresponding gpiochip, holding static
32 * data for this device
33 * @list: links gpio_device:s together for traversal
35 * This state container holds most of the runtime variable data
36 * for a GPIO device and can hold references and live on after the
37 * GPIO chip has been removed, if it is still being used from
45 struct gpio_chip *chip;
46 struct list_head list;
50 * struct acpi_gpio_info - ACPI GPIO specific information
51 * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
52 * @active_low: in case of @gpioint, the pin is active low
54 struct acpi_gpio_info {
60 /* gpio suffixes used for ACPI and device tree lookup */
61 static const char * const gpio_suffixes[] = { "gpios", "gpio" };
64 void acpi_gpiochip_add(struct gpio_chip *chip);
65 void acpi_gpiochip_remove(struct gpio_chip *chip);
67 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
68 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
70 struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
71 const char *propname, int index,
72 struct acpi_gpio_info *info);
73 struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
74 const char *propname, int index,
75 struct acpi_gpio_info *info);
77 int acpi_gpio_count(struct device *dev, const char *con_id);
79 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id);
81 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
82 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
85 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
88 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
90 static inline struct gpio_desc *
91 acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname,
92 int index, struct acpi_gpio_info *info)
94 return ERR_PTR(-ENOSYS);
96 static inline struct gpio_desc *
97 acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
98 int index, struct acpi_gpio_info *info)
100 return ERR_PTR(-ENXIO);
102 static inline int acpi_gpio_count(struct device *dev, const char *con_id)
107 static inline bool acpi_can_fallback_to_crs(struct acpi_device *adev,
114 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
115 const char *list_name, int index, enum of_gpio_flags *flags);
117 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
119 extern struct spinlock gpio_lock;
120 extern struct list_head gpio_devices;
123 struct gpio_chip *chip;
125 /* flag symbols are bit numbers */
126 #define FLAG_REQUESTED 0
127 #define FLAG_IS_OUT 1
128 #define FLAG_EXPORT 2 /* protected by sysfs_lock */
129 #define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */
130 #define FLAG_ACTIVE_LOW 6 /* value has active low */
131 #define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */
132 #define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */
133 #define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */
134 #define FLAG_IS_HOGGED 11 /* GPIO is hogged */
136 /* Connection label */
138 /* Name of the GPIO */
142 int gpiod_request(struct gpio_desc *desc, const char *label);
143 void gpiod_free(struct gpio_desc *desc);
144 int gpiod_hog(struct gpio_desc *desc, const char *name,
145 unsigned long lflags, enum gpiod_flags dflags);
148 * Return the GPIO number of the passed descriptor relative to its chip
150 static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
152 return desc - &desc->chip->desc[0];
155 /* With descriptor prefix */
157 #define gpiod_emerg(desc, fmt, ...) \
158 pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
160 #define gpiod_crit(desc, fmt, ...) \
161 pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
163 #define gpiod_err(desc, fmt, ...) \
164 pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
166 #define gpiod_warn(desc, fmt, ...) \
167 pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
169 #define gpiod_info(desc, fmt, ...) \
170 pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
172 #define gpiod_dbg(desc, fmt, ...) \
173 pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
176 /* With chip prefix */
178 #define chip_emerg(chip, fmt, ...) \
179 dev_emerg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
180 #define chip_crit(chip, fmt, ...) \
181 dev_crit(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
182 #define chip_err(chip, fmt, ...) \
183 dev_err(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
184 #define chip_warn(chip, fmt, ...) \
185 dev_warn(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
186 #define chip_info(chip, fmt, ...) \
187 dev_info(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
188 #define chip_dbg(chip, fmt, ...) \
189 dev_dbg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
191 #ifdef CONFIG_GPIO_SYSFS
193 int gpiochip_sysfs_register(struct gpio_chip *chip);
194 void gpiochip_sysfs_unregister(struct gpio_chip *chip);
198 static inline int gpiochip_sysfs_register(struct gpio_chip *chip)
203 static inline void gpiochip_sysfs_unregister(struct gpio_chip *chip)
207 #endif /* CONFIG_GPIO_SYSFS */
209 #endif /* GPIOLIB_H */