[SCSI] Add spi_populate_*_msg functions

Introduce new helpers:
 - spi_populate_width_msg()
 - spi_populate_sync_msg()
 - spi_populate_ppr_msg()

and use them in drivers which already enable the SPI transport.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/53c700.c b/drivers/scsi/53c700.c
index 4ce7438..6a0f950 100644
--- a/drivers/scsi/53c700.c
+++ b/drivers/scsi/53c700.c
@@ -238,14 +238,6 @@
 	"MSG IN",
 };
 
-static __u8 NCR_700_SDTR_msg[] = {
-	0x01,			/* Extended message */
-	0x03,			/* Extended message Length */
-	0x01,			/* SDTR Extended message */
-	NCR_700_MIN_PERIOD,
-	NCR_700_MAX_OFFSET
-};
-
 /* This translates the SDTR message offset and period to a value
  * which can be loaded into the SXFER_REG.
  *
@@ -266,7 +258,7 @@
 		return 0;
 
 	if(period < hostdata->min_period) {
-		printk(KERN_WARNING "53c700: Period %dns is less than this chip's minimum, setting to %d\n", period*4, NCR_700_SDTR_msg[3]*4);
+		printk(KERN_WARNING "53c700: Period %dns is less than this chip's minimum, setting to %d\n", period*4, NCR_700_MIN_PERIOD*4);
 		period = hostdata->min_period;
 	}
 	XFERP = (period*4 * hostdata->sync_clock)/1000 - 4;
@@ -1434,11 +1426,9 @@
 
 	if(hostdata->fast &&
 	   NCR_700_is_flag_clear(SCp->device, NCR_700_DEV_NEGOTIATED_SYNC)) {
-		memcpy(&hostdata->msgout[count], NCR_700_SDTR_msg,
-		       sizeof(NCR_700_SDTR_msg));
-		hostdata->msgout[count+3] = spi_period(SCp->device->sdev_target);
-		hostdata->msgout[count+4] = spi_offset(SCp->device->sdev_target);
-		count += sizeof(NCR_700_SDTR_msg);
+		count += spi_populate_sync_msg(&hostdata->msgout[count],
+				spi_period(SCp->device->sdev_target),
+				spi_offset(SCp->device->sdev_target));
 		NCR_700_set_flag(SCp->device, NCR_700_DEV_BEGIN_SYNC_NEGOTIATION);
 	}
 
diff --git a/drivers/scsi/aha152x.c b/drivers/scsi/aha152x.c
index cb2ee25..67d78ed 100644
--- a/drivers/scsi/aha152x.c
+++ b/drivers/scsi/aha152x.c
@@ -1708,12 +1708,7 @@
 		ADDMSGO(BUS_DEVICE_RESET);
 	} else if (SYNCNEG==0 && SYNCHRONOUS) {
     		CURRENT_SC->SCp.phase |= syncneg;
-		ADDMSGO(EXTENDED_MESSAGE);
-		ADDMSGO(3);
-		ADDMSGO(EXTENDED_SDTR);
-		ADDMSGO(50);		/* 200ns */
-		ADDMSGO(8);		/* 8 byte req/ack offset */
-
+		MSGOLEN += spi_populate_sync_msg(&MSGO(MSGOLEN), 50, 8);
 		SYNCNEG=1;		/* negotiation in progress */
 	}
 
diff --git a/drivers/scsi/aic7xxx/aic79xx_core.c b/drivers/scsi/aic7xxx/aic79xx_core.c
index 342f779..b6266fd 100644
--- a/drivers/scsi/aic7xxx/aic79xx_core.c
+++ b/drivers/scsi/aic7xxx/aic79xx_core.c
@@ -3762,11 +3762,8 @@
 {
 	if (offset == 0)
 		period = AHD_ASYNC_XFER_PERIOD;
-	ahd->msgout_buf[ahd->msgout_index++] = MSG_EXTENDED;
-	ahd->msgout_buf[ahd->msgout_index++] = MSG_EXT_SDTR_LEN;
-	ahd->msgout_buf[ahd->msgout_index++] = MSG_EXT_SDTR;
-	ahd->msgout_buf[ahd->msgout_index++] = period;
-	ahd->msgout_buf[ahd->msgout_index++] = offset;
+	ahd->msgout_index += spi_populate_sync_msg(
+			ahd->msgout_buf + ahd->msgout_index, period, offset);
 	ahd->msgout_len += 5;
 	if (bootverbose) {
 		printf("(%s:%c:%d:%d): Sending SDTR period %x, offset %x\n",
@@ -3783,10 +3780,8 @@
 ahd_construct_wdtr(struct ahd_softc *ahd, struct ahd_devinfo *devinfo,
 		   u_int bus_width)
 {
-	ahd->msgout_buf[ahd->msgout_index++] = MSG_EXTENDED;
-	ahd->msgout_buf[ahd->msgout_index++] = MSG_EXT_WDTR_LEN;
-	ahd->msgout_buf[ahd->msgout_index++] = MSG_EXT_WDTR;
-	ahd->msgout_buf[ahd->msgout_index++] = bus_width;
+	ahd->msgout_index += spi_populate_width_msg(
+			ahd->msgout_buf + ahd->msgout_index, bus_width);
 	ahd->msgout_len += 4;
 	if (bootverbose) {
 		printf("(%s:%c:%d:%d): Sending WDTR %x\n",
@@ -3813,14 +3808,9 @@
 		ppr_options |= MSG_EXT_PPR_PCOMP_EN;
 	if (offset == 0)
 		period = AHD_ASYNC_XFER_PERIOD;
-	ahd->msgout_buf[ahd->msgout_index++] = MSG_EXTENDED;
-	ahd->msgout_buf[ahd->msgout_index++] = MSG_EXT_PPR_LEN;
-	ahd->msgout_buf[ahd->msgout_index++] = MSG_EXT_PPR;
-	ahd->msgout_buf[ahd->msgout_index++] = period;
-	ahd->msgout_buf[ahd->msgout_index++] = 0;
-	ahd->msgout_buf[ahd->msgout_index++] = offset;
-	ahd->msgout_buf[ahd->msgout_index++] = bus_width;
-	ahd->msgout_buf[ahd->msgout_index++] = ppr_options;
+	ahd->msgout_index += spi_populate_ppr_msg(
+			ahd->msgout_buf + ahd->msgout_index, period, offset,
+			bus_width, ppr_options);
 	ahd->msgout_len += 8;
 	if (bootverbose) {
 		printf("(%s:%c:%d:%d): Sending PPR bus_width %x, period %x, "
diff --git a/drivers/scsi/aic7xxx/aic7xxx_core.c b/drivers/scsi/aic7xxx/aic7xxx_core.c
index 58ac461..d375669 100644
--- a/drivers/scsi/aic7xxx/aic7xxx_core.c
+++ b/drivers/scsi/aic7xxx/aic7xxx_core.c
@@ -2461,11 +2461,8 @@
 {
 	if (offset == 0)
 		period = AHC_ASYNC_XFER_PERIOD;
-	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXTENDED;
-	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXT_SDTR_LEN;
-	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXT_SDTR;
-	ahc->msgout_buf[ahc->msgout_index++] = period;
-	ahc->msgout_buf[ahc->msgout_index++] = offset;
+	ahc->msgout_index += spi_populate_sync_msg(
+			ahc->msgout_buf + ahc->msgout_index, period, offset);
 	ahc->msgout_len += 5;
 	if (bootverbose) {
 		printf("(%s:%c:%d:%d): Sending SDTR period %x, offset %x\n",
@@ -2482,10 +2479,8 @@
 ahc_construct_wdtr(struct ahc_softc *ahc, struct ahc_devinfo *devinfo,
 		   u_int bus_width)
 {
-	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXTENDED;
-	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXT_WDTR_LEN;
-	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXT_WDTR;
-	ahc->msgout_buf[ahc->msgout_index++] = bus_width;
+	ahc->msgout_index += spi_populate_width_msg(
+			ahc->msgout_buf + ahc->msgout_index, bus_width);
 	ahc->msgout_len += 4;
 	if (bootverbose) {
 		printf("(%s:%c:%d:%d): Sending WDTR %x\n",
@@ -2505,14 +2500,9 @@
 {
 	if (offset == 0)
 		period = AHC_ASYNC_XFER_PERIOD;
-	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXTENDED;
-	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXT_PPR_LEN;
-	ahc->msgout_buf[ahc->msgout_index++] = MSG_EXT_PPR;
-	ahc->msgout_buf[ahc->msgout_index++] = period;
-	ahc->msgout_buf[ahc->msgout_index++] = 0;
-	ahc->msgout_buf[ahc->msgout_index++] = offset;
-	ahc->msgout_buf[ahc->msgout_index++] = bus_width;
-	ahc->msgout_buf[ahc->msgout_index++] = ppr_options;
+	ahc->msgout_index += spi_populate_ppr_msg(
+			ahc->msgout_buf + ahc->msgout_index, period, offset,
+			bus_width, ppr_options);
 	ahc->msgout_len += 8;
 	if (bootverbose) {
 		printf("(%s:%c:%d:%d): Sending PPR bus_width %x, period %x, "
diff --git a/drivers/scsi/ncr53c8xx.c b/drivers/scsi/ncr53c8xx.c
index abb1859..22f9131 100644
--- a/drivers/scsi/ncr53c8xx.c
+++ b/drivers/scsi/ncr53c8xx.c
@@ -4105,17 +4105,11 @@
 
 	switch (nego) {
 	case NS_SYNC:
-		msgptr[msglen++] = EXTENDED_MESSAGE;
-		msgptr[msglen++] = 3;
-		msgptr[msglen++] = EXTENDED_SDTR;
-		msgptr[msglen++] = tp->maxoffs ? tp->minsync : 0;
-		msgptr[msglen++] = tp->maxoffs;
+		msglen += spi_populate_sync_msg(msgptr + msglen,
+				tp->maxoffs ? tp->minsync : 0, tp->maxoffs);
 		break;
 	case NS_WIDE:
-		msgptr[msglen++] = EXTENDED_MESSAGE;
-		msgptr[msglen++] = 2;
-		msgptr[msglen++] = EXTENDED_WDTR;
-		msgptr[msglen++] = tp->usrwide;
+		msglen += spi_populate_width_msg(msgptr + msglen, tp->usrwide);
 		break;
 	}
 
@@ -6989,12 +6983,7 @@
 		spi_offset(starget) = ofs;
 		ncr_setsync(np, cp, scntl3, (fak<<5)|ofs);
 
-		np->msgout[0] = EXTENDED_MESSAGE;
-		np->msgout[1] = 3;
-		np->msgout[2] = EXTENDED_SDTR;
-		np->msgout[3] = per;
-		np->msgout[4] = ofs;
-
+		spi_populate_sync_msg(np->msgout, per, ofs);
 		cp->nego_status = NS_SYNC;
 
 		if (DEBUG_FLAGS & DEBUG_NEGO) {
@@ -7080,11 +7069,7 @@
 
 		spi_width(starget) = wide;
 		ncr_setwide(np, cp, wide, 1);
-
-		np->msgout[0] = EXTENDED_MESSAGE;
-		np->msgout[1] = 2;
-		np->msgout[2] = EXTENDED_WDTR;
-		np->msgout[3] = wide;
+		spi_populate_width_msg(np->msgout, wide);
 
 		np->msgin [0] = NOP;
 
diff --git a/drivers/scsi/scsi_transport_spi.c b/drivers/scsi/scsi_transport_spi.c
index 97f4be62..c0051a4 100644
--- a/drivers/scsi/scsi_transport_spi.c
+++ b/drivers/scsi/scsi_transport_spi.c
@@ -1051,6 +1051,39 @@
 }
 EXPORT_SYMBOL(spi_display_xfer_agreement);
 
+int spi_populate_width_msg(unsigned char *msg, int width)
+{
+	msg[0] = EXTENDED_MESSAGE;
+	msg[1] = 2;
+	msg[2] = EXTENDED_WDTR;
+	msg[3] = width;
+	return 4;
+}
+
+int spi_populate_sync_msg(unsigned char *msg, int period, int offset)
+{
+	msg[0] = EXTENDED_MESSAGE;
+	msg[1] = 3;
+	msg[2] = EXTENDED_SDTR;
+	msg[3] = period;
+	msg[4] = offset;
+	return 5;
+}
+
+int spi_populate_ppr_msg(unsigned char *msg, int period, int offset,
+		int width, int options)
+{
+	msg[0] = EXTENDED_MESSAGE;
+	msg[1] = 6;
+	msg[2] = EXTENDED_PPR;
+	msg[3] = period;
+	msg[4] = 0;
+	msg[5] = offset;
+	msg[6] = width;
+	msg[7] = options;
+	return 8;
+}
+
 #ifdef CONFIG_SCSI_CONSTANTS
 static const char * const one_byte_msgs[] = {
 /* 0x00 */ "Command Complete", NULL, "Save Pointers",
diff --git a/drivers/scsi/sym53c8xx_2/sym_hipd.c b/drivers/scsi/sym53c8xx_2/sym_hipd.c
index f4854c3..620b472 100644
--- a/drivers/scsi/sym53c8xx_2/sym_hipd.c
+++ b/drivers/scsi/sym53c8xx_2/sym_hipd.c
@@ -40,7 +40,6 @@
 
 #include <linux/slab.h>
 #include <asm/param.h>		/* for timeouts in units of HZ */
-#include <scsi/scsi_dbg.h>
 
 #include "sym_glue.h"
 #include "sym_nvram.h"
@@ -1430,29 +1429,18 @@
 
 	switch (nego) {
 	case NS_SYNC:
-		msgptr[msglen++] = M_EXTENDED;
-		msgptr[msglen++] = 3;
-		msgptr[msglen++] = M_X_SYNC_REQ;
-		msgptr[msglen++] = goal->period;
-		msgptr[msglen++] = goal->offset;
+		msglen += spi_populate_sync_msg(msgptr + msglen, goal->period,
+				goal->offset);
 		break;
 	case NS_WIDE:
-		msgptr[msglen++] = M_EXTENDED;
-		msgptr[msglen++] = 2;
-		msgptr[msglen++] = M_X_WIDE_REQ;
-		msgptr[msglen++] = goal->width;
+		msglen += spi_populate_width_msg(msgptr + msglen, goal->width);
 		break;
 	case NS_PPR:
-		msgptr[msglen++] = M_EXTENDED;
-		msgptr[msglen++] = 6;
-		msgptr[msglen++] = M_X_PPR_REQ;
-		msgptr[msglen++] = goal->period;
-		msgptr[msglen++] = 0;
-		msgptr[msglen++] = goal->offset;
-		msgptr[msglen++] = goal->width;
-		msgptr[msglen++] = (goal->iu ? PPR_OPT_IU : 0) |
+		msglen += spi_populate_ppr_msg(msgptr + msglen, goal->period,
+				goal->offset, goal->width,
+				(goal->iu ? PPR_OPT_IU : 0) |
 					(goal->dt ? PPR_OPT_DT : 0) |
-					(goal->qas ? PPR_OPT_QAS : 0);
+					(goal->qas ? PPR_OPT_QAS : 0));
 		break;
 	}
 
@@ -3948,11 +3936,7 @@
 	/*
 	 *  It was a request. Prepare an answer message.
 	 */
-	np->msgout[0] = M_EXTENDED;
-	np->msgout[1] = 3;
-	np->msgout[2] = M_X_SYNC_REQ;
-	np->msgout[3] = per;
-	np->msgout[4] = ofs;
+	spi_populate_sync_msg(np->msgout, per, ofs);
 
 	if (DEBUG_FLAGS & DEBUG_NEGO) {
 		sym_print_nego_msg(np, target, "sync msgout", np->msgout);
@@ -4078,14 +4062,7 @@
 	/*
 	 *  It was a request. Prepare an answer message.
 	 */
-	np->msgout[0] = M_EXTENDED;
-	np->msgout[1] = 6;
-	np->msgout[2] = M_X_PPR_REQ;
-	np->msgout[3] = per;
-	np->msgout[4] = 0;
-	np->msgout[5] = ofs;
-	np->msgout[6] = wide;
-	np->msgout[7] = opts;
+	spi_populate_ppr_msg(np->msgout, per, ofs, wide, opts);
 
 	if (DEBUG_FLAGS & DEBUG_NEGO) {
 		sym_print_nego_msg(np, target, "ppr msgout", np->msgout);
@@ -4197,10 +4174,7 @@
 	/*
 	 *  It was a request. Prepare an answer message.
 	 */
-	np->msgout[0] = M_EXTENDED;
-	np->msgout[1] = 2;
-	np->msgout[2] = M_X_WIDE_REQ;
-	np->msgout[3] = wide;
+	spi_populate_width_msg(np->msgout, wide);
 
 	np->msgin [0] = M_NOOP;
 
@@ -4245,11 +4219,8 @@
 		 * a single SCSI command (Suggested by Justin Gibbs).
 		 */
 		if (tp->tgoal.offset) {
-			np->msgout[0] = M_EXTENDED;
-			np->msgout[1] = 3;
-			np->msgout[2] = M_X_SYNC_REQ;
-			np->msgout[3] = tp->tgoal.period;
-			np->msgout[4] = tp->tgoal.offset;
+			spi_populate_sync_msg(np->msgout, tp->tgoal.period,
+					tp->tgoal.offset);
 
 			if (DEBUG_FLAGS & DEBUG_NEGO) {
 				sym_print_nego_msg(np, cp->target,