ncr5380: Fix NCR5380_select() EH checks and result handling

Add missing checks for EH abort during arbitration and selection.
Rework the handling of NCR5380_select() result to improve clarity.

Fixes: 707d62b37fbb ("ncr5380: Fix EH during arbitration and selection")
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Cc: <stable@vger.kernel.org> # 4.5
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/drivers/scsi/NCR5380.c b/drivers/scsi/NCR5380.c
index b1b3fac..e8e579a 100644
--- a/drivers/scsi/NCR5380.c
+++ b/drivers/scsi/NCR5380.c
@@ -815,15 +815,17 @@
 	struct NCR5380_hostdata *hostdata =
 		container_of(work, struct NCR5380_hostdata, main_task);
 	struct Scsi_Host *instance = hostdata->host;
-	struct scsi_cmnd *cmd;
 	int done;
 
 	do {
 		done = 1;
 
 		spin_lock_irq(&hostdata->lock);
-		while (!hostdata->connected &&
-		       (cmd = dequeue_next_cmd(instance))) {
+		while (!hostdata->connected && !hostdata->selecting) {
+			struct scsi_cmnd *cmd = dequeue_next_cmd(instance);
+
+			if (!cmd)
+				break;
 
 			dsprintk(NDEBUG_MAIN, instance, "main: dequeued %p\n", cmd);
 
@@ -840,8 +842,7 @@
 			 * entire unit.
 			 */
 
-			cmd = NCR5380_select(instance, cmd);
-			if (!cmd) {
+			if (!NCR5380_select(instance, cmd)) {
 				dsprintk(NDEBUG_MAIN, instance, "main: select complete\n");
 			} else {
 				dsprintk(NDEBUG_MAIN | NDEBUG_QUEUES, instance,
@@ -1056,6 +1057,11 @@
 		/* Reselection interrupt */
 		goto out;
 	}
+	if (!hostdata->selecting) {
+		/* Command was aborted */
+		NCR5380_write(MODE_REG, MR_BASE);
+		goto out;
+	}
 	if (err < 0) {
 		NCR5380_write(MODE_REG, MR_BASE);
 		shost_printk(KERN_ERR, instance,