/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_GPIO_MACHINE_H
#define __LINUX_GPIO_MACHINE_H

#include <linux/types.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_PULL_DISABLE               = (1 << 6),

        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[];
};

/*
 * Helper for lookup tables with just one single lookup for a device.
 */
#define GPIO_LOOKUP_SINGLE(_name, _dev_id, _key, _chip_hwnum, _con_id, _flags) \
static struct gpiod_lookup_table _name = {                              \
        .dev_id = _dev_id,                                              \
        .table = {                                                      \
                GPIO_LOOKUP(_key, _chip_hwnum, _con_id, _flags),        \
                {},                                                     \
        },                                                              \
}

/*
 * 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)         \
(struct gpiod_lookup) {                                                   \
        .key = _key,                                                      \
        .chip_hwnum = _chip_hwnum,                                        \
        .con_id = _con_id,                                                \
        .idx = _idx,                                                      \
        .flags = _flags,                                                  \
}

#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);
#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) {}
#endif /* CONFIG_GPIOLIB */

#endif /* __LINUX_GPIO_MACHINE_H */