+static int nv_adma_use_reg_mode(struct ata_queued_cmd *qc)
+{
+ struct nv_adma_port_priv *pp = qc->ap->private_data;
+
+ /* ADMA engine can only be used for non-ATAPI DMA commands,
+ or interrupt-driven no-data commands. */
+ if((pp->flags & NV_ADMA_ATAPI_SETUP_COMPLETE) ||
+ (qc->tf.flags & ATA_TFLAG_POLLING))
+ return 1;
+
+ if((qc->flags & ATA_QCFLAG_DMAMAP) ||
+ (qc->tf.protocol == ATA_PROT_NODATA))
+ return 0;
+
+ return 1;
+}
+