ide: remove wmb() from ide-dma-sff.c and scc_pata.c

This patch:
o replaces "mask" variable in ide_dma_end() with #define.
o removes use of wmb() in ide-dma-sff.c and scc_pata.c.
o is not tested - I don't have (or want) the HW.

Signed-off-by: Grant Grundler <grundler@google.com>
Cc: KOBAYASHI Yoshitake <yoshitake.kobayashi@toshiba.co.jp>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/ide-dma-sff.c

@@ -277,8 +277,6 @@ void ide_dma_start(ide_drive_t *drive)
 		dma_cmd = inb(hwif->dma_base + ATA_DMA_CMD);
 		outb(dma_cmd | ATA_DMA_START, hwif->dma_base + ATA_DMA_CMD);
 	}
-
-	wmb();
 }
 EXPORT_SYMBOL_GPL(ide_dma_start);
 
@@ -286,7 +284,7 @@ EXPORT_SYMBOL_GPL(ide_dma_start);
 int ide_dma_end(ide_drive_t *drive)
 {
 	ide_hwif_t *hwif = drive->hwif;
-	u8 dma_stat = 0, dma_cmd = 0, mask;
+	u8 dma_stat = 0, dma_cmd = 0;
 
 	/* stop DMA */
 	if (hwif->host_flags & IDE_HFLAG_MMIO) {
@@ -304,11 +302,10 @@ int ide_dma_end(ide_drive_t *drive)
 	/* clear INTR & ERROR bits */
 	ide_dma_sff_write_status(hwif, dma_stat | ATA_DMA_ERR | ATA_DMA_INTR);
 
-	wmb();
+#define CHECK_DMA_MASK (ATA_DMA_ACTIVE | ATA_DMA_ERR | ATA_DMA_INTR)
 
 	/* verify good DMA status */
-	mask = ATA_DMA_ACTIVE | ATA_DMA_ERR | ATA_DMA_INTR;
-	if ((dma_stat & mask) != ATA_DMA_INTR)
+	if ((dma_stat & CHECK_DMA_MASK) != ATA_DMA_INTR)
 		return 0x10 | dma_stat;
 	return 0;
 }

drivers/ide/scc_pata.c

@@ -337,7 +337,6 @@ static void scc_dma_start(ide_drive_t *drive)
 
 	/* start DMA */
 	scc_ide_outb(dma_cmd | 1, hwif->dma_base);
-	wmb();
 }
 
 static int __scc_dma_end(ide_drive_t *drive)
@@ -354,7 +353,6 @@ static int __scc_dma_end(ide_drive_t *drive)
 	/* clear the INTR & ERROR bits */
 	scc_ide_outb(dma_stat | 6, hwif->dma_base + 4);
 	/* verify good DMA status */
-	wmb();
 	return (dma_stat & 7) != 4 ? (0x10 | dma_stat) : 0;
 }