v4l2_frequency 1422 include/linux/videodev2.h #define VIDIOC_G_FREQUENCY _IOWR('V', 56, struct v4l2_frequency) v4l2_frequency 1423 include/linux/videodev2.h #define VIDIOC_S_FREQUENCY _IOW('V', 57, struct v4l2_frequency) v4l2_frequency 211 include/media/v4l2-ioctl.h struct v4l2_frequency *a); v4l2_frequency 213 include/media/v4l2-ioctl.h struct v4l2_frequency *a);