Camera board • VIDIOC_SUBDEV_S_FMT has no effect

Code:

#include <stdint.h>#include <stdio.h>#include <fcntl.h>#include <string.h>#include <sys/ioctl.h>#include <linux/v4l2-subdev.h>#include <linux/v4l2-mediabus.h>int main(int argc, const char *argv[]){uint32_t fmtbus[4];const char *device = "/dev/v4l-subdev0";uint32_t width = 1448;uint32_t height = 1088;struct v4l2_subdev_format ffs = {0};if (argc > 1)device = argv[1];int ret = -1;int fd = open(device, O_RDWR);if (fd < 0){printf("error on open %s %m\n", device);return -1;}fmtbus[0] = 0x3007;ffs.pad = 0;ffs.stream = 0;ffs.which = V4L2_SUBDEV_FORMAT_ACTIVE;ret = ioctl(fd, VIDIOC_SUBDEV_G_FMT, &ffs);if (ret)printf("subdev_g_fmt error %m\n");fmtbus[1] = ffs.format.code;memset(&ffs, 0, sizeof(ffs));ffs.pad = 0;ffs.stream = 0;ffs.which = V4L2_SUBDEV_FORMAT_ACTIVE;ffs.format.width = width;ffs.format.height = height;ffs.format.code = fmtbus[0];ffs.format.field = V4L2_FIELD_NONE;ret = ioctl(fd, VIDIOC_SUBDEV_S_FMT, &ffs);if (ret)printf("subdev_g_fmt error %m\n");memset(&ffs, 0, sizeof(ffs));ffs.pad = 0;ffs.stream = 0;ffs.which = V4L2_SUBDEV_FORMAT_ACTIVE;ret = ioctl(fd, VIDIOC_SUBDEV_G_FMT, &ffs);if (ret)printf("subdev_g_fmt error %m\n");fmtbus[2] = ffs.format.code;printf("code %#lx => req(%#lx) => %#lx\n", fmtbus[1], fmtbus[0], fmtbus[2]);return 0;}

Code:

code 0x300f => req(0x3007) = > 0x300f