ioctl VIDIOC_S_HW_FREQ_SEEK &manvol; VIDIOC_S_HW_FREQ_SEEK Perform a hardware frequency seek int ioctl int fd int request struct v4l2_hw_freq_seek *argp fd &fd; request VIDIOC_S_HW_FREQ_SEEK argp Start a hardware frequency seek from the current frequency. To do this applications initialize the tuner, type, seek_upward, wrap_around, spacing, rangelow and rangehigh fields, and zero out the reserved array of a &v4l2-hw-freq-seek; and call the VIDIOC_S_HW_FREQ_SEEK ioctl with a pointer to this structure. The rangelow and rangehigh fields can be set to a non-zero value to tell the driver to search a specific band. If the &v4l2-tuner; capability field has the V4L2_TUNER_CAP_HWSEEK_PROG_LIM flag set, these values must fall within one of the bands returned by &VIDIOC-ENUM-FREQ-BANDS;. If the V4L2_TUNER_CAP_HWSEEK_PROG_LIM flag is not set, then these values must exactly match those of one of the bands returned by &VIDIOC-ENUM-FREQ-BANDS;. If the current frequency of the tuner does not fall within the selected band it will be clamped to fit in the band before the seek is started. If an error is returned, then the original frequency will be restored. This ioctl is supported if the V4L2_CAP_HW_FREQ_SEEK capability is set. If this ioctl is called from a non-blocking filehandle, then &EAGAIN; is returned and no seek takes place. &cs-str; __u32 tuner The tuner index number. This is the same value as in the &v4l2-input; tuner field and the &v4l2-tuner; index field. __u32 type The tuner type. This is the same value as in the &v4l2-tuner; type field. See __u32 seek_upward If non-zero, seek upward from the current frequency, else seek downward. __u32 wrap_around If non-zero, wrap around when at the end of the frequency range, else stop seeking. The &v4l2-tuner; capability field will tell you what the hardware supports. __u32 spacing If non-zero, defines the hardware seek resolution in Hz. The driver selects the nearest value that is supported by the device. If spacing is zero a reasonable default value is used. __u32 rangelow If non-zero, the lowest tunable frequency of the band to search in units of 62.5 kHz, or if the &v4l2-tuner; capability field has the V4L2_TUNER_CAP_LOW flag set, in units of 62.5 Hz or if the &v4l2-tuner; capability field has the V4L2_TUNER_CAP_1HZ flag set, in units of 1 Hz. If rangelow is zero a reasonable default value is used. __u32 rangehigh If non-zero, the highest tunable frequency of the band to search in units of 62.5 kHz, or if the &v4l2-tuner; capability field has the V4L2_TUNER_CAP_LOW flag set, in units of 62.5 Hz or if the &v4l2-tuner; capability field has the V4L2_TUNER_CAP_1HZ flag set, in units of 1 Hz. If rangehigh is zero a reasonable default value is used. __u32 reserved[5] Reserved for future extensions. Applications must set the array to zero. &return-value; EINVAL The tuner index is out of bounds, the wrap_around value is not supported or one of the values in the type, rangelow or rangehigh fields is wrong. EAGAIN Attempted to call VIDIOC_S_HW_FREQ_SEEK with the filehandle in non-blocking mode. ENODATA The hardware seek found no channels. EBUSY Another hardware seek is already in progress.