ncr5380: Use runtime register mapping

Convert compile-time C400_ register mapping to runtime mapping.
This removes the weird negative register offsets and allows adding
additional mappings.

While at it, convert read/write loops into insb/outsb.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/drivers/scsi/NCR5380.h b/drivers/scsi/NCR5380.h
index ee83ab5..a792886 100644
--- a/drivers/scsi/NCR5380.h
+++ b/drivers/scsi/NCR5380.h
@@ -163,8 +163,7 @@
 /* Write any value to this register to start an ini mode DMA receive */
 #define START_DMA_INITIATOR_RECEIVE_REG 7	/* wo */
 
-#define C400_CONTROL_STATUS_REG NCR53C400_register_offset-8	/* rw */
-
+/* NCR 53C400(A) Control Status Register bits: */
 #define CSR_RESET              0x80	/* wo  Resets 53c400 */
 #define CSR_53C80_REG          0x80	/* ro  5380 registers busy */
 #define CSR_TRANS_DIR          0x40	/* rw  Data transfer direction */
@@ -181,16 +180,6 @@
 #define CSR_BASE CSR_53C80_INTR
 #endif
 
-/* Number of 128-byte blocks to be transferred */
-#define C400_BLOCK_COUNTER_REG   NCR53C400_register_offset-7	/* rw */
-
-/* Resume transfer after disconnect */
-#define C400_RESUME_TRANSFER_REG NCR53C400_register_offset-6	/* wo */
-
-/* Access to host buffer stack */
-#define C400_HOST_BUFFER         NCR53C400_register_offset-4	/* rw */
-
-
 /* Note : PHASE_* macros are based on the values of the STATUS register */
 #define PHASE_MASK 	(SR_MSG | SR_CD | SR_IO)