[SCSI] aic7xxx: fix the BIOS limits setting routines

Following the go around over the SONY DVD that needs artificial limits,
this should be the correct code for all cases (minus the debugging
prints).

Signed-off-by: James Bottomley <[e-mail]>

drivers/scsi/aic7xxx/aic7xxx_osm.c

···
 	memset(targ, 0, sizeof(*targ));
 
 	if (sc) {
-		if ((ahc->features & AHC_ULTRA2) != 0) {
-			scsirate = sc->device_flags[target_offset] & CFXFER;
-		} else {
-			scsirate = (sc->device_flags[target_offset] & CFXFER) << 4;
-			if (sc->device_flags[target_offset] & CFSYNCH)
-				scsirate |= SOFS;
+		int maxsync = AHC_SYNCRATE_DT;
+		int ultra = 0;
+		int flags = sc->device_flags[target_offset];
+
+		if (ahc->flags & AHC_NEWEEPROM_FMT) {
+		    if (flags & CFSYNCHISULTRA)
+			ultra = 1;
+		} else if (flags & CFULTRAEN)
+			ultra = 1;
+		/* AIC nutcase; 10MHz appears as ultra = 1, CFXFER = 0x04
+		 * change it to ultra=0, CFXFER = 0 */
+		if(ultra && (flags & CFXFER) == 0x04) {
+			ultra = 0;
+			flags &= ~CFXFER;
 		}
-		if (sc->device_flags[target_offset] & CFWIDEB) {
-			scsirate |= WIDEXFER;
-			spi_max_width(starget) = 1;
-		} else
-			spi_max_width(starget) = 0;
+	    
+		if ((ahc->features & AHC_ULTRA2) != 0) {
+			scsirate = (flags & CFXFER) | (ultra ? 0x8 : 0);
+		} else {
+			scsirate = (flags & CFXFER) << 4;
+			maxsync = ultra ? AHC_SYNCRATE_ULTRA : 
+				AHC_SYNCRATE_FAST;
+		}
+		spi_max_width(starget) = (flags & CFWIDEB) ? 1 : 0;
+		if (!(flags & CFSYNCH))
+			spi_max_offset(starget) = 0;
 		spi_min_period(starget) = 
-			ahc_find_period(ahc, scsirate, AHC_SYNCRATE_DT);
+			ahc_find_period(ahc, scsirate, maxsync);
+
 		tinfo = ahc_fetch_transinfo(ahc, channel, ahc->our_id,
 					    starget->id, &tstate);
 	}