serverworks: cleanup ->set_dma_mode method

IDE core guarantees that ->set_dma_mode will be called only
for DMA modes set in SWDMA/MWDMA/UDMA masks.

There should be no functionality changes caused by this patch.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/pci/serverworks.c b/drivers/ide/pci/serverworks.c
index e9bd269..877c09b 100644
--- a/drivers/ide/pci/serverworks.c
+++ b/drivers/ide/pci/serverworks.c
@@ -164,25 +164,12 @@
 	ultra_timing	&= ~(0x0F << (4*unit));
 	ultra_enable	&= ~(0x01 << drive->dn);
 
-	switch(speed) {
-		case XFER_MW_DMA_2:
-		case XFER_MW_DMA_1:
-		case XFER_MW_DMA_0:
-			dma_timing |= dma_modes[speed - XFER_MW_DMA_0];
-			break;
-
-		case XFER_UDMA_5:
-		case XFER_UDMA_4:
-		case XFER_UDMA_3:
-		case XFER_UDMA_2:
-		case XFER_UDMA_1:
-		case XFER_UDMA_0:
-			dma_timing   |= dma_modes[2];
-			ultra_timing |= ((udma_modes[speed - XFER_UDMA_0]) << (4*unit));
-			ultra_enable |= (0x01 << drive->dn);
-		default:
-			break;
-	}
+	if (speed >= XFER_UDMA_0) {
+		dma_timing   |= dma_modes[2];
+		ultra_timing |= (udma_modes[speed - XFER_UDMA_0] << (4 * unit));
+		ultra_enable |= (0x01 << drive->dn);
+	} else if (speed >= XFER_MW_DMA_0)
+		dma_timing   |= dma_modes[speed - XFER_MW_DMA_0];
 
 	pci_write_config_byte(dev, drive_pci2[drive->dn], dma_timing);
 	pci_write_config_byte(dev, (0x56|hwif->channel), ultra_timing);