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// SPDX-License-Identifier: LGPL-2.1-or-later
// SPDX-FileCopyrightText: 2021 Bartosz Golaszewski <brgl@bgdev.pl>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <gpiod.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "internal.h"
struct gpiod_chip {
int fd;
char *path;
};
GPIOD_API struct gpiod_chip *gpiod_chip_open(const char *path)
{
struct gpiod_chip *chip;
int fd;
if (!path) {
errno = EINVAL;
return NULL;
}
if (!gpiod_check_gpiochip_device(path, true))
return NULL;
fd = open(path, O_RDWR | O_CLOEXEC);
if (fd < 0)
return NULL;
chip = malloc(sizeof(*chip));
if (!chip)
goto err_close_fd;
memset(chip, 0, sizeof(*chip));
chip->path = strdup(path);
if (!chip->path)
goto err_free_chip;
chip->fd = fd;
return chip;
err_free_chip:
free(chip);
err_close_fd:
close(fd);
return NULL;
}
GPIOD_API void gpiod_chip_close(struct gpiod_chip *chip)
{
if (!chip)
return;
close(chip->fd);
free(chip->path);
free(chip);
}
static int read_chip_info(int fd, struct gpiochip_info *info)
{
int ret;
memset(info, 0, sizeof(*info));
ret = gpiod_ioctl(fd, GPIO_GET_CHIPINFO_IOCTL, info);
if (ret)
return -1;
return 0;
}
GPIOD_API struct gpiod_chip_info *gpiod_chip_get_info(struct gpiod_chip *chip)
{
struct gpiochip_info info;
int ret;
assert(chip);
ret = read_chip_info(chip->fd, &info);
if (ret)
return NULL;
return gpiod_chip_info_from_uapi(&info);
}
GPIOD_API const char *gpiod_chip_get_path(struct gpiod_chip *chip)
{
assert(chip);
return chip->path;
}
static int chip_read_line_info(int fd, unsigned int offset,
struct gpio_v2_line_info *info, bool watch)
{
int ret, cmd;
memset(info, 0, sizeof(*info));
info->offset = offset;
cmd = watch ? GPIO_V2_GET_LINEINFO_WATCH_IOCTL :
GPIO_V2_GET_LINEINFO_IOCTL;
ret = gpiod_ioctl(fd, cmd, info);
if (ret)
return -1;
return 0;
}
static struct gpiod_line_info *
chip_get_line_info(struct gpiod_chip *chip, unsigned int offset, bool watch)
{
struct gpio_v2_line_info info;
int ret;
assert(chip);
ret = chip_read_line_info(chip->fd, offset, &info, watch);
if (ret)
return NULL;
return gpiod_line_info_from_uapi(&info);
}
GPIOD_API struct gpiod_line_info *
gpiod_chip_get_line_info(struct gpiod_chip *chip, unsigned int offset)
{
return chip_get_line_info(chip, offset, false);
}
GPIOD_API struct gpiod_line_info *
gpiod_chip_watch_line_info(struct gpiod_chip *chip, unsigned int offset)
{
return chip_get_line_info(chip, offset, true);
}
GPIOD_API int gpiod_chip_unwatch_line_info(struct gpiod_chip *chip,
unsigned int offset)
{
assert(chip);
return gpiod_ioctl(chip->fd, GPIO_GET_LINEINFO_UNWATCH_IOCTL, &offset);
}
GPIOD_API int gpiod_chip_get_fd(struct gpiod_chip *chip)
{
assert(chip);
return chip->fd;
}
GPIOD_API int gpiod_chip_wait_info_event(struct gpiod_chip *chip,
int64_t timeout_ns)
{
assert(chip);
return gpiod_poll_fd(chip->fd, timeout_ns);
}
GPIOD_API struct gpiod_info_event *
gpiod_chip_read_info_event(struct gpiod_chip *chip)
{
assert(chip);
return gpiod_info_event_read_fd(chip->fd);
}
GPIOD_API int gpiod_chip_get_line_offset_from_name(struct gpiod_chip *chip,
const char *name)
{
struct gpio_v2_line_info linfo;
struct gpiochip_info chinfo;
unsigned int offset;
int ret;
assert(chip);
if (!name) {
errno = EINVAL;
return -1;
}
ret = read_chip_info(chip->fd, &chinfo);
if (ret)
return -1;
for (offset = 0; offset < chinfo.lines; offset++) {
ret = chip_read_line_info(chip->fd, offset, &linfo, false);
if (ret)
return -1;
if (strcmp(name, linfo.name) == 0)
return offset;
}
errno = ENOENT;
return -1;
}
GPIOD_API struct gpiod_line_request *
gpiod_chip_request_lines(struct gpiod_chip *chip,
struct gpiod_request_config *req_cfg,
struct gpiod_line_config *line_cfg)
{
struct gpio_v2_line_request uapi_req;
struct gpiod_line_request *request;
struct gpiochip_info info;
int ret;
assert(chip);
if (!line_cfg) {
errno = EINVAL;
return NULL;
}
memset(&uapi_req, 0, sizeof(uapi_req));
if (req_cfg)
gpiod_request_config_to_uapi(req_cfg, &uapi_req);
ret = gpiod_line_config_to_uapi(line_cfg, &uapi_req);
if (ret)
return NULL;
ret = read_chip_info(chip->fd, &info);
if (ret)
return NULL;
ret = gpiod_ioctl(chip->fd, GPIO_V2_GET_LINE_IOCTL, &uapi_req);
if (ret)
return NULL;
request = gpiod_line_request_from_uapi(&uapi_req, info.name);
if (!request) {
close(uapi_req.fd);
return NULL;
}
return request;
}
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