ide: use standard timing for XFER_PIO_SLOW mode in ide_timing_compute()

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/ide/ide-timings.c b/drivers/ide/ide-timings.c
index 001a563..c6053ab 100644
--- a/drivers/ide/ide-timings.c
+++ b/drivers/ide/ide-timings.c
@@ -166,12 +166,13 @@
 	if (id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE drive */
 		memset(&p, 0, sizeof(p));
 
-		if (speed <= XFER_PIO_2)
-			p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO];
-		else if ((speed <= XFER_PIO_4) ||
-			 (speed == XFER_PIO_5 && !ata_id_is_cfa(id)))
-			p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO_IORDY];
-		else if (speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2)
+		if (speed >= XFER_PIO_0 && speed <= XFER_SW_DMA_0) {
+			if (speed <= XFER_PIO_2)
+				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO];
+			else if ((speed <= XFER_PIO_4) ||
+				 (speed == XFER_PIO_5 && !ata_id_is_cfa(id)))
+				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO_IORDY];
+		} else if (speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2)
 			p.cycle = id[ATA_ID_EIDE_DMA_MIN];
 
 		ide_timing_merge(&p, t, t, IDE_TIMING_CYCLE | IDE_TIMING_CYC8B);