linuxdebug/include/linux/gpio/machine.h

129 lines
4.4 KiB
C

/* 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_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[];
};
/**
* 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;
};
/*
* 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, \
}
/*
* Simple definition of a single GPIO hog in an array.
*/
#define GPIO_HOG(_chip_label, _chip_hwnum, _line_name, _lflags, _dflags) \
(struct gpiod_hog) { \
.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);
void gpiod_remove_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) {}
static inline void gpiod_remove_hogs(struct gpiod_hog *hogs) {}
#endif /* CONFIG_GPIOLIB */
#endif /* __LINUX_GPIO_MACHINE_H */