I checked it and you're right. I patched scan.c (from dvbscan) to use INVERSION_OFF:I can tell you this much: if (param->inversion != INVERSION_ON && param->inversion != INVERSION_OFF) return -EINVAL; The driver will only accept INVERSION_ON and INVERSION_OFF, but dvbscan used INVERSION_AUTO in your case, that's why you got these "WARNING: >>> tuning failed!!!" messages with it. You need to tell dvbscan to use INVERSION_OFF. Not sure how to do that, though.
WARNING: >>> tuning failed!!!tune to: 706000000:INVERSION_OFF:BANDWIDTH_8_MHZ:FEC_1_2:FEC_AUTO:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_4:HIERARCHY_NONE