set_dma_speed
extern void set_dma_speed(unsigned int chan, int cycle_ns);
EXPORT_SYMBOL(set_dma_speed);
set_dma_speed(state->dma, state->port[ap->port_no].speed[qc->dev->devno]);
set_dma_speed(info->info.scsi.dma, 180);
set_dma_speed(info->info.scsi.dma, 180);
set_dma_speed(info->info.scsi.dma, 180);