diff --git a/drivers/ide/ide-dma-sff.c b/drivers/ide/ide-dma-sff.c
index 1f2a5f5..f6d2d44 100644
--- a/drivers/ide/ide-dma-sff.c
+++ b/drivers/ide/ide-dma-sff.c
@@ -176,15 +176,10 @@
 {
 	ide_hwif_t *hwif = drive->hwif;
 	struct request *rq = hwif->hwgroup->rq;
-	unsigned int reading;
+	unsigned int reading = rq_data_dir(rq) ? 0 : ATA_DMA_WR;
 	u8 mmio = (hwif->host_flags & IDE_HFLAG_MMIO) ? 1 : 0;
 	u8 dma_stat;
 
-	if (rq_data_dir(rq))
-		reading = 0;
-	else
-		reading = 1 << 3;
-
 	/* fall back to pio! */
 	if (!ide_build_dmatable(drive, rq)) {
 		ide_map_sg(drive, rq);
@@ -209,10 +204,11 @@
 
 	/* clear INTR & ERROR flags */
 	if (mmio)
-		writeb(dma_stat | 6,
+		writeb(dma_stat | ATA_DMA_ERR | ATA_DMA_INTR,
 		       (void __iomem *)(hwif->dma_base + ATA_DMA_STATUS));
 	else
-		outb(dma_stat | 6, hwif->dma_base + ATA_DMA_STATUS);
+		outb(dma_stat | ATA_DMA_ERR | ATA_DMA_INTR,
+		     hwif->dma_base + ATA_DMA_STATUS);
 
 	drive->waiting_for_dma = 1;
 	return 0;
@@ -246,14 +242,13 @@
 
 	hwif->hwgroup->expiry = NULL;	/* one free ride for now */
 
-	/* 1 dmaing, 2 error, 4 intr */
-	if (dma_stat & 2)	/* ERROR */
+	if (dma_stat & ATA_DMA_ERR)	/* ERROR */
 		return -1;
 
-	if (dma_stat & 1)	/* DMAing */
+	if (dma_stat & ATA_DMA_ACTIVE)	/* DMAing */
 		return WAIT_CMD;
 
-	if (dma_stat & 4)	/* Got an Interrupt */
+	if (dma_stat & ATA_DMA_INTR)	/* Got an Interrupt */
 		return WAIT_CMD;
 
 	return 0;	/* Status is unknown -- reset the bus */
@@ -279,12 +274,11 @@
 	 */
 	if (hwif->host_flags & IDE_HFLAG_MMIO) {
 		dma_cmd = readb((void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
-		/* start DMA */
-		writeb(dma_cmd | 1,
+		writeb(dma_cmd | ATA_DMA_START,
 		       (void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
 	} else {
 		dma_cmd = inb(hwif->dma_base + ATA_DMA_CMD);
-		outb(dma_cmd | 1, hwif->dma_base + ATA_DMA_CMD);
+		outb(dma_cmd | ATA_DMA_START, hwif->dma_base + ATA_DMA_CMD);
 	}
 
 	wmb();
@@ -296,19 +290,18 @@
 {
 	ide_hwif_t *hwif = drive->hwif;
 	u8 mmio = (hwif->host_flags & IDE_HFLAG_MMIO) ? 1 : 0;
-	u8 dma_stat = 0, dma_cmd = 0;
+	u8 dma_stat = 0, dma_cmd = 0, mask;
 
 	drive->waiting_for_dma = 0;
 
+	/* stop DMA */
 	if (mmio) {
-		/* get DMA command mode */
 		dma_cmd = readb((void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
-		/* stop DMA */
-		writeb(dma_cmd & ~1,
+		writeb(dma_cmd & ~ATA_DMA_START,
 		       (void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
 	} else {
 		dma_cmd = inb(hwif->dma_base + ATA_DMA_CMD);
-		outb(dma_cmd & ~1, hwif->dma_base + ATA_DMA_CMD);
+		outb(dma_cmd & ~ATA_DMA_START, hwif->dma_base + ATA_DMA_CMD);
 	}
 
 	/* get DMA status */
@@ -316,16 +309,21 @@
 
 	if (mmio)
 		/* clear the INTR & ERROR bits */
-		writeb(dma_stat | 6,
+		writeb(dma_stat | ATA_DMA_ERR | ATA_DMA_INTR,
 		       (void __iomem *)(hwif->dma_base + ATA_DMA_STATUS));
 	else
-		outb(dma_stat | 6, hwif->dma_base + ATA_DMA_STATUS);
+		outb(dma_stat | ATA_DMA_ERR | ATA_DMA_INTR,
+		     hwif->dma_base + ATA_DMA_STATUS);
 
 	/* purge DMA mappings */
 	ide_destroy_dmatable(drive);
-	/* verify good DMA status */
 	wmb();
-	return (dma_stat & 7) != 4 ? (0x10 | dma_stat) : 0;
+
+	/* verify good DMA status */
+	mask = ATA_DMA_ACTIVE | ATA_DMA_ERR | ATA_DMA_INTR;
+	if ((dma_stat & mask) != ATA_DMA_INTR)
+		return 0x10 | dma_stat;
+	return 0;
 }
 EXPORT_SYMBOL_GPL(ide_dma_end);
 
@@ -335,11 +333,7 @@
 	ide_hwif_t *hwif = drive->hwif;
 	u8 dma_stat = hwif->tp_ops->read_sff_dma_status(hwif);
 
-	/* return 1 if INTR asserted */
-	if ((dma_stat & 4) == 4)
-		return 1;
-
-	return 0;
+	return (dma_stat & ATA_DMA_INTR) ? 1 : 0;
 }
 EXPORT_SYMBOL_GPL(ide_dma_test_irq);