+/**
+ * ata_bmdma_qc_issue - issue taskfile to a BMDMA controller
+ * @qc: command to issue to device
+ *
+ * This function issues a PIO, NODATA or DMA command to a
+ * SFF/BMDMA controller. PIO and NODATA are handled by
+ * ata_sff_qc_issue().
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ *
+ * RETURNS:
+ * Zero on success, AC_ERR_* mask on failure
+ */
+unsigned int ata_bmdma_qc_issue(struct ata_queued_cmd *qc)
+{
+ struct ata_port *ap = qc->ap;
+
+ /* see ata_dma_blacklisted() */
+ BUG_ON((ap->flags & ATA_FLAG_PIO_POLLING) &&
+ qc->tf.protocol == ATAPI_PROT_DMA);
+
+ /* defer PIO handling to sff_qc_issue */
+ if (!ata_is_dma(qc->tf.protocol))
+ return ata_sff_qc_issue(qc);
+
+ /* select the device */
+ ata_dev_select(ap, qc->dev->devno, 1, 0);
+
+ /* start the command */
+ switch (qc->tf.protocol) {
+ case ATA_PROT_DMA:
+ WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
+
+ ap->ops->sff_tf_load(ap, &qc->tf); /* load tf registers */
+ ap->ops->bmdma_setup(qc); /* set up bmdma */
+ ap->ops->bmdma_start(qc); /* initiate bmdma */
+ ap->hsm_task_state = HSM_ST_LAST;
+ break;
+
+ case ATAPI_PROT_DMA:
+ WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
+
+ ap->ops->sff_tf_load(ap, &qc->tf); /* load tf registers */
+ ap->ops->bmdma_setup(qc); /* set up bmdma */
+ ap->hsm_task_state = HSM_ST_FIRST;
+
+ /* send cdb by polling if no cdb interrupt */
+ if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
+ ata_sff_queue_pio_task(ap, 0);
+ break;
+
+ default:
+ WARN_ON(1);
+ return AC_ERR_SYSTEM;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ata_bmdma_qc_issue);
+