sata_fsl,mv,nv: prepare for NCQ command completion update

Make the following changes to prepare for NCQ command completion
update.  Changes made by this patch don't cause any functional
difference.

* sata_fsl_host_intr(): rename the local variable qc_active to
  done_mask as that's what it is.

* mv_process_crpb_response(): restructure if clause for easier update.

* nv_adma_interrupt(): drop unnecessary error variable.

* nv_swncq_sdbfis(): drop unnecessary nr_done and return 0 on success.
  Typo fix.

* nv_swncq_dmafis(): drop unused return value and return void.

* nv_swncq_host_interrupt(): drop unnecessary return value handling.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ashish Kalra <ashish.kalra@freescale.com>
Cc: Saeed Bishara <saeed@marvell.com>
Cc: Mark Lord <liml@rtr.ca>
Cc: Robert Hancock <hancockr@shaw.ca>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/sata_fsl.c

@@ -1096,7 +1096,7 @@ static void sata_fsl_host_intr(struct ata_port *ap)
 {
 	struct sata_fsl_host_priv *host_priv = ap->host->private_data;
 	void __iomem *hcr_base = host_priv->hcr_base;
-	u32 hstatus, qc_active = 0;
+	u32 hstatus, done_mask = 0;
 	struct ata_queued_cmd *qc;
 	u32 SError;
 
@@ -1116,28 +1116,28 @@ static void sata_fsl_host_intr(struct ata_port *ap)
 	}
 
 	/* Read command completed register */
-	qc_active = ioread32(hcr_base + CC);
+	done_mask = ioread32(hcr_base + CC);
 
 	VPRINTK("Status of all queues :\n");
-	VPRINTK("qc_active/CC = 0x%x, CA = 0x%x, CE=0x%x,CQ=0x%x,apqa=0x%x\n",
-		qc_active,
+	VPRINTK("done_mask/CC = 0x%x, CA = 0x%x, CE=0x%x,CQ=0x%x,apqa=0x%x\n",
+		done_mask,
 		ioread32(hcr_base + CA),
 		ioread32(hcr_base + CE),
 		ioread32(hcr_base + CQ),
 		ap->qc_active);
 
-	if (qc_active & ap->qc_active) {
+	if (done_mask & ap->qc_active) {
 		int i;
 		/* clear CC bit, this will also complete the interrupt */
-		iowrite32(qc_active, hcr_base + CC);
+		iowrite32(done_mask, hcr_base + CC);
 
 		DPRINTK("Status of all queues :\n");
-		DPRINTK("qc_active/CC = 0x%x, CA = 0x%x, CE=0x%x\n",
-			qc_active, ioread32(hcr_base + CA),
+		DPRINTK("done_mask/CC = 0x%x, CA = 0x%x, CE=0x%x\n",
+			done_mask, ioread32(hcr_base + CA),
 			ioread32(hcr_base + CE));
 
 		for (i = 0; i < SATA_FSL_QUEUE_DEPTH; i++) {
-			if (qc_active & (1 << i)) {
+			if (done_mask & (1 << i)) {
 				qc = ata_qc_from_tag(ap, i);
 				if (qc) {
 					ata_qc_complete(qc);
@@ -1164,7 +1164,7 @@ static void sata_fsl_host_intr(struct ata_port *ap)
 		/* Spurious Interrupt!! */
 		DPRINTK("spurious interrupt!!, CC = 0x%x\n",
 			ioread32(hcr_base + CC));
-		iowrite32(qc_active, hcr_base + CC);
+		iowrite32(done_mask, hcr_base + CC);
 		return;
 	}
 }