linux/drivers/gpio/gpiolib.h
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   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
  21enum of_gpio_flags;
  22enum gpiod_flags;
  23enum gpio_lookup_flags;
  24struct 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 */
  51struct 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 */
  82struct acpi_gpio_info {
  83        bool gpioint;
  84        int polarity;
  85        int triggering;
  86};
  87
  88/* gpio suffixes used for ACPI and device tree lookup */
  89static const char * const gpio_suffixes[] = { "gpios", "gpio" };
  90
  91#ifdef CONFIG_OF_GPIO
  92struct gpio_desc *of_find_gpio(struct device *dev,
  93                               const char *con_id,
  94                               unsigned int idx,
  95                               enum gpio_lookup_flags *flags);
  96struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
  97                   const char *list_name, int index, enum of_gpio_flags *flags);
  98int of_gpiochip_add(struct gpio_chip *gc);
  99void of_gpiochip_remove(struct gpio_chip *gc);
 100#else
 101static 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}
 108static 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}
 113static inline int of_gpiochip_add(struct gpio_chip *gc) { return 0; }
 114static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
 115#endif /* CONFIG_OF_GPIO */
 116
 117#ifdef CONFIG_ACPI
 118void acpi_gpiochip_add(struct gpio_chip *chip);
 119void acpi_gpiochip_remove(struct gpio_chip *chip);
 120
 121void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
 122void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
 123
 124struct 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);
 129struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
 130                                      const char *propname, int index,
 131                                      struct acpi_gpio_info *info);
 132
 133int acpi_gpio_count(struct device *dev, const char *con_id);
 134
 135bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id);
 136#else
 137static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
 138static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
 139
 140static inline void
 141acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
 142
 143static inline void
 144acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
 145
 146static inline struct gpio_desc *
 147acpi_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}
 153static inline struct gpio_desc *
 154acpi_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}
 159static inline int acpi_gpio_count(struct device *dev, const char *con_id)
 160{
 161        return -ENODEV;
 162}
 163
 164static inline bool acpi_can_fallback_to_crs(struct acpi_device *adev,
 165                                            const char *con_id)
 166{
 167        return false;
 168}
 169#endif
 170
 171struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
 172void 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
 177extern struct spinlock gpio_lock;
 178extern struct list_head gpio_devices;
 179
 180struct 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
 200int gpiod_request(struct gpio_desc *desc, const char *label);
 201void gpiod_free(struct gpio_desc *desc);
 202int 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 */
 208static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
 209{
 210        return desc - &desc->gdev->descs[0];
 211}
 212
 213void 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
 253int gpiochip_sysfs_register(struct gpio_device *gdev);
 254void gpiochip_sysfs_unregister(struct gpio_device *gdev);
 255
 256#else
 257
 258static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
 259{
 260        return 0;
 261}
 262
 263static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
 264{
 265}
 266
 267#endif /* CONFIG_GPIO_SYSFS */
 268
 269#endif /* GPIOLIB_H */
 270