camera-streamer/device/v4l2/device_media.c
2022-09-02 22:00:01 +02:00

139 lines
3.1 KiB
C

#include "v4l2.h"
#include "device/device.h"
#include "util/opts/log.h"
#include <unistd.h>
#include <dirent.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/sysmacros.h>
#include <linux/media.h>
int v4l2_device_open_media_device(device_t *dev)
{
struct stat st;
if (fstat(dev->v4l2->dev_fd, &st) < 0) {
LOG_VERBOSE(dev, "Cannot get fstat");
return -1;
}
if (~st.st_mode & S_IFCHR) {
LOG_VERBOSE(dev, "FD is not char");
return -1;
}
char path[300];
sprintf(path, "/sys/dev/char/%d:%d/device", major(st.st_rdev), minor(st.st_rdev));
struct dirent **namelist;
int n = scandir(path, &namelist, NULL, NULL);
if (n < 0) {
LOG_VERBOSE(dev, "Cannot scan: %s", path);
return -1;
}
int ret = -1;
while (n--) {
if (ret == -1 && strstr(namelist[n]->d_name, "media") == namelist[n]->d_name) {
path[0] = 0;
sprintf(path, "/dev/%s", namelist[n]->d_name);
ret = open(path, O_RDWR);
if (ret >= 0) {
LOG_VERBOSE(dev, "Opened '%s' (fd=%d)", path, ret);
}
}
free(namelist[n]);
}
free(namelist);
return ret;
}
int v4l2_device_open_v4l2_subdev(device_t *dev, int subdev)
{
int media_fd = -1;
unsigned int last_id = 0;
int ret = -1;
media_fd = v4l2_device_open_media_device(dev);
if (media_fd < 0) {
LOG_VERBOSE(dev, "Cannot find media controller");
return -1;
}
for (;;) {
struct media_entity_desc entity = {
.id = MEDIA_ENT_ID_FLAG_NEXT | last_id,
};
int rc = ioctl(media_fd, MEDIA_IOC_ENUM_ENTITIES, &entity);
if (rc < 0 && errno == EINVAL) {
break;
}
if (rc < 0) {
goto error;
}
last_id = entity.id;
char path[256];
sprintf(path, "/sys/dev/char/%d:%d", entity.dev.major, entity.dev.minor);
char link[256];
if ((rc = readlink(path, link, sizeof(link)-1)) < 0) {
LOG_VERBOSE(dev, "Cannot readlink '%s'", path);
}
link[rc] = 0;
char *last = strrchr(link, '/');
if (!last) {
LOG_VERBOSE(dev, "Link '%s' for '%s' does not end with '/'", link, path);
goto error;
}
if (strstr(last, "/v4l-subdev") != last) {
LOG_VERBOSE(dev, "Link '%s' does not contain '/v4l-subdev'", link);
goto error;
}
sprintf(path, "/dev%s", last);
ret = open(path, O_RDWR);
if (ret < 0) {
LOG_ERROR(dev, "Cannot open '%s' (ret=%d)", path, ret);
goto error;
}
LOG_VERBOSE(dev, "Opened '%s' (fd=%d)", path, ret);
break;
}
error:
close(media_fd);
return ret;
}
int v4l2_device_set_pad_format(device_t *dev, unsigned width, unsigned height, unsigned format)
{
struct v4l2_subdev_format fmt = {0};
if (dev->v4l2->subdev_fd < 0) {
return -1;
}
fmt.pad = 0;
fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
fmt.format.code = format;
fmt.format.width = width;
fmt.format.height = height;
fmt.format.colorspace = V4L2_COLORSPACE_RAW;
fmt.format.field = V4L2_FIELD_ANY;
LOG_DEBUG(dev, "Configuring mpad %d (subdev_fd=%d)...", fmt.pad, dev->v4l2->subdev_fd);
ERR_IOCTL(dev, dev->v4l2->subdev_fd, VIDIOC_SUBDEV_S_FMT, &fmt, "Can't configure mpad %d (subdev_fd=%d)", fmt.pad, dev->v4l2->subdev_fd);
return 0;
error:
return -1;
}