v4l2_fwht_get_pixfmt
const struct v4l2_fwht_pixfmt_info *v4l2_fwht_get_pixfmt(u32 idx);
const struct v4l2_fwht_pixfmt_info *info = v4l2_fwht_get_pixfmt(0);
info = v4l2_fwht_get_pixfmt(0);
info = v4l2_fwht_get_pixfmt(f->index);