LXR linux/include/linux/gpio/machine.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef __LINUX_GPIO_MACHINE_H
   3#define __LINUX_GPIO_MACHINE_H
   4
   5#include <linux/types.h>
   6#include <linux/list.h>
   7
   8enum gpio_lookup_flags {
   9        GPIO_ACTIVE_HIGH                = (0 << 0),
  10        GPIO_ACTIVE_LOW                 = (1 << 0),
  11        GPIO_OPEN_DRAIN                 = (1 << 1),
  12        GPIO_OPEN_SOURCE                = (1 << 2),
  13        GPIO_PERSISTENT                 = (0 << 3),
  14        GPIO_TRANSITORY                 = (1 << 3),
  15        GPIO_PULL_UP                    = (1 << 4),
  16        GPIO_PULL_DOWN                  = (1 << 5),
  17
  18        GPIO_LOOKUP_FLAGS_DEFAULT       = GPIO_ACTIVE_HIGH | GPIO_PERSISTENT,
  19};
  20
  21/**
  22 * struct gpiod_lookup - lookup table
  23 * @key: either the name of the chip the GPIO belongs to, or the GPIO line name
  24 *       Note that GPIO line names are not guaranteed to be globally unique,
  25 *       so this will use the first match found!
  26 * @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO, or
  27 *              U16_MAX to indicate that @key is a GPIO line name
  28 * @con_id: name of the GPIO from the device's point of view
  29 * @idx: index of the GPIO in case several GPIOs share the same name
  30 * @flags: bitmask of gpio_lookup_flags GPIO_* values
  31 *
  32 * gpiod_lookup is a lookup table for associating GPIOs to specific devices and
  33 * functions using platform data.
  34 */
  35struct gpiod_lookup {
  36        const char *key;
  37        u16 chip_hwnum;
  38        const char *con_id;
  39        unsigned int idx;
  40        unsigned long flags;
  41};
  42
  43struct gpiod_lookup_table {
  44        struct list_head list;
  45        const char *dev_id;
  46        struct gpiod_lookup table[];
  47};
  48
  49/**
  50 * struct gpiod_hog - GPIO line hog table
  51 * @chip_label: name of the chip the GPIO belongs to
  52 * @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO
  53 * @line_name: consumer name for the hogged line
  54 * @lflags: bitmask of gpio_lookup_flags GPIO_* values
  55 * @dflags: GPIO flags used to specify the direction and value
  56 */
  57struct gpiod_hog {
  58        struct list_head list;
  59        const char *chip_label;
  60        u16 chip_hwnum;
  61        const char *line_name;
  62        unsigned long lflags;
  63        int dflags;
  64};
  65
  66/*
  67 * Simple definition of a single GPIO under a con_id
  68 */
  69#define GPIO_LOOKUP(_key, _chip_hwnum, _con_id, _flags) \
  70        GPIO_LOOKUP_IDX(_key, _chip_hwnum, _con_id, 0, _flags)
  71
  72/*
  73 * Use this macro if you need to have several GPIOs under the same con_id.
  74 * Each GPIO needs to use a different index and can be accessed using
  75 * gpiod_get_index()
  76 */
  77#define GPIO_LOOKUP_IDX(_key, _chip_hwnum, _con_id, _idx, _flags)         \
  78(struct gpiod_lookup) {                                                   \
  79        .key = _key,                                                      \
  80        .chip_hwnum = _chip_hwnum,                                        \
  81        .con_id = _con_id,                                                \
  82        .idx = _idx,                                                      \
  83        .flags = _flags,                                                  \
  84}
  85
  86/*
  87 * Simple definition of a single GPIO hog in an array.
  88 */
  89#define GPIO_HOG(_chip_label, _chip_hwnum, _line_name, _lflags, _dflags)  \
  90(struct gpiod_hog) {                                                      \
  91        .chip_label = _chip_label,                                        \
  92        .chip_hwnum = _chip_hwnum,                                        \
  93        .line_name = _line_name,                                          \
  94        .lflags = _lflags,                                                \
  95        .dflags = _dflags,                                                \
  96}
  97
  98#ifdef CONFIG_GPIOLIB
  99void gpiod_add_lookup_table(struct gpiod_lookup_table *table);
 100void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n);
 101void gpiod_remove_lookup_table(struct gpiod_lookup_table *table);
 102void gpiod_add_hogs(struct gpiod_hog *hogs);
 103#else /* ! CONFIG_GPIOLIB */
 104static inline
 105void gpiod_add_lookup_table(struct gpiod_lookup_table *table) {}
 106static inline
 107void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) {}
 108static inline
 109void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) {}
 110static inline void gpiod_add_hogs(struct gpiod_hog *hogs) {}
 111#endif /* CONFIG_GPIOLIB */
 112
 113#endif /* __LINUX_GPIO_MACHINE_H */
 114