text: /* SPDX-License-Identifier: GPL-2.0 */
  #ifndef __LINUX_GPIO_MACHINE_H
  #define __LINUX_GPIO_MACHINE_H
  
  #include <linux/types.h>
  #include <linux/list.h>
  
  enum gpio_lookup_flags {
  	GPIO_ACTIVE_HIGH		= (0 << 0),
  	GPIO_ACTIVE_LOW			= (1 << 0),
  	GPIO_OPEN_DRAIN			= (1 << 1),
  	GPIO_OPEN_SOURCE		= (1 << 2),
  	GPIO_PERSISTENT			= (0 << 3),
  	GPIO_TRANSITORY			= (1 << 3),
  	GPIO_PULL_UP			= (1 << 4),
  	GPIO_PULL_DOWN			= (1 << 5),
  
  	GPIO_LOOKUP_FLAGS_DEFAULT	= GPIO_ACTIVE_HIGH | GPIO_PERSISTENT,
  };
  
  /**
   * struct gpiod_lookup - lookup table
   * @key: either the name of the chip the GPIO belongs to, or the GPIO line name
   *       Note that GPIO line names are not guaranteed to be globally unique,
   *       so this will use the first match found!
   * @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO, or
   *              U16_MAX to indicate that @key is a GPIO line name
   * @con_id: name of the GPIO from the device's point of view
   * @idx: index of the GPIO in case several GPIOs share the same name
   * @flags: bitmask of gpio_lookup_flags GPIO_* values
   *
   * gpiod_lookup is a lookup table for associating GPIOs to specific devices and
   * functions using platform data.
   */
  struct gpiod_lookup {
  	const char *key;
  	u16 chip_hwnum;
  	const char *con_id;
  	unsigned int idx;
  	unsigned long flags;
  };
  
  struct gpiod_lookup_table {
  	struct list_head list;
  	const char *dev_id;
  	struct gpiod_lookup table[];
  };
  
  /**
   * struct gpiod_hog - GPIO line hog table
   * @chip_label: name of the chip the GPIO belongs to
   * @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO
   * @line_name: consumer name for the hogged line
   * @lflags: bitmask of gpio_lookup_flags GPIO_* values
   * @dflags: GPIO flags used to specify the direction and value
   */
  struct gpiod_hog {
  	struct list_head list;
  	const char *chip_label;
  	u16 chip_hwnum;
  	const char *line_name;
  	unsigned long lflags;
  	int dflags;
  };
  
  /*
   * Simple definition of a single GPIO under a con_id
   */
  #define GPIO_LOOKUP(_key, _chip_hwnum, _con_id, _flags) \
  	GPIO_LOOKUP_IDX(_key, _chip_hwnum, _con_id, 0, _flags)
  
  /*
   * Use this macro if you need to have several GPIOs under the same con_id.
   * Each GPIO needs to use a different index and can be accessed using
   * gpiod_get_index()
   */
  #define GPIO_LOOKUP_IDX(_key, _chip_hwnum, _con_id, _idx, _flags)         \
  {                                                                         \
  	.key = _key,                                                      \
  	.chip_hwnum = _chip_hwnum,                                        \
  	.con_id = _con_id,                                                \
  	.idx = _idx,                                                      \
  	.flags = _flags,                                                  \
  }
  
  /*
   * Simple definition of a single GPIO hog in an array.
   */
  #define GPIO_HOG(_chip_label, _chip_hwnum, _line_name, _lflags, _dflags)  \
  {                                                                         \
  	.chip_label = _chip_label,                                        \
  	.chip_hwnum = _chip_hwnum,                                        \
  	.line_name = _line_name,                                          \
  	.lflags = _lflags,                                                \
  	.dflags = _dflags,                                                \
  }
  
  #ifdef CONFIG_GPIOLIB
  void gpiod_add_lookup_table(struct gpiod_lookup_table *table);
  void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n);
  void gpiod_remove_lookup_table(struct gpiod_lookup_table *table);
  void gpiod_add_hogs(struct gpiod_hog *hogs);
  #else /* ! CONFIG_GPIOLIB */
  static inline
  void gpiod_add_lookup_table(struct gpiod_lookup_table *table) {}
  static inline
  void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) {}
  static inline
  void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) {}
  static inline void gpiod_add_hogs(struct gpiod_hog *hogs) {}
  #endif /* CONFIG_GPIOLIB */
  
  #endif /* __LINUX_GPIO_MACHINE_H */
  