diff --git a/drivers/scsi/NCR5380.c b/drivers/scsi/NCR5380.c
index e17e64e3e0d9657f157ecf6c50ee7a03ddb9930f..c4b80219868dd673b386ed4b1ef4956c8f44c617 100644
--- a/drivers/scsi/NCR5380.c
+++ b/drivers/scsi/NCR5380.c
@@ -574,12 +574,12 @@ static int __init __maybe_unused NCR5380_probe_irq(struct Scsi_Host *instance,
 	int trying_irqs, i, mask;
 	NCR5380_setup(instance);
 
-	for (trying_irqs = i = 0, mask = 1; i < 16; ++i, mask <<= 1)
+	for (trying_irqs = 0, i = 1, mask = 2; i < 16; ++i, mask <<= 1)
 		if ((mask & possible) && (request_irq(i, &probe_intr, 0, "NCR-probe", NULL) == 0))
 			trying_irqs |= mask;
 
 	timeout = jiffies + (250 * HZ / 1000);
-	probe_irq = SCSI_IRQ_NONE;
+	probe_irq = NO_IRQ;
 
 	/*
 	 * A interrupt is triggered whenever BSY = false, SEL = true
@@ -596,13 +596,13 @@ static int __init __maybe_unused NCR5380_probe_irq(struct Scsi_Host *instance,
 	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL);
 
-	while (probe_irq == SCSI_IRQ_NONE && time_before(jiffies, timeout))
+	while (probe_irq == NO_IRQ && time_before(jiffies, timeout))
 		schedule_timeout_uninterruptible(1);
 	
 	NCR5380_write(SELECT_ENABLE_REG, 0);
 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
 
-	for (i = 0, mask = 1; i < 16; ++i, mask <<= 1)
+	for (i = 1, mask = 2; i < 16; ++i, mask <<= 1)
 		if (trying_irqs & mask)
 			free_irq(i, NULL);
 
@@ -730,7 +730,7 @@ static int __maybe_unused NCR5380_show_info(struct seq_file *m,
 
 	SPRINTF("\nBase Addr: 0x%05lX    ", (long) instance->base);
 	SPRINTF("io_port: %04x      ", (int) instance->io_port);
-	if (instance->irq == SCSI_IRQ_NONE)
+	if (instance->irq == NO_IRQ)
 		SPRINTF("IRQ: None.\n");
 	else
 		SPRINTF("IRQ: %d.\n", instance->irq);
@@ -1501,7 +1501,7 @@ static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd *cmd)
 	}
 
 	dprintk(NDEBUG_SELECTION, "scsi%d : target %d selected, going into MESSAGE OUT phase.\n", instance->host_no, cmd->device->id);
-	tmp[0] = IDENTIFY(((instance->irq == SCSI_IRQ_NONE) ? 0 : 1), cmd->device->lun);
+	tmp[0] = IDENTIFY(((instance->irq == NO_IRQ) ? 0 : 1), cmd->device->lun);
 
 	len = 1;
 	cmd->tag = 0;
diff --git a/drivers/scsi/NCR5380.h b/drivers/scsi/NCR5380.h
index f09d560fb6b27201c295064c2f7c12fbca538cfb..4b0c628952ee252d20f9a9ccc476af2c82f9eb4d 100644
--- a/drivers/scsi/NCR5380.h
+++ b/drivers/scsi/NCR5380.h
@@ -232,12 +232,15 @@
  * Scsi_Host structure
  */
 
-#define SCSI_IRQ_NONE	255
 #define DMA_NONE	255
 #define IRQ_AUTO	254
 #define DMA_AUTO	254
 #define PORT_AUTO	0xffff	/* autoprobe io port for 53c400a */
 
+#ifndef NO_IRQ
+#define NO_IRQ		0
+#endif
+
 #define FLAG_HAS_LAST_BYTE_SENT		1	/* NCR53c81 or better */
 #define FLAG_CHECK_LAST_BYTE_SENT	2	/* Only test once */
 #define FLAG_NCR53C400			4	/* NCR53c400 */
diff --git a/drivers/scsi/arm/oak.c b/drivers/scsi/arm/oak.c
index f62cc904a47b86e621a9805d7982925aa7d8cd9a..13d5995531fca416be70535829db82431a59967d 100644
--- a/drivers/scsi/arm/oak.c
+++ b/drivers/scsi/arm/oak.c
@@ -148,7 +148,7 @@ static int oakscsi_probe(struct expansion_card *ec, const struct ecard_id *id)
 		goto unreg;
 	}
 
-	host->irq = IRQ_NONE;
+	host->irq = NO_IRQ;
 	host->n_io_port = 255;
 
 	NCR5380_init(host, 0);
diff --git a/drivers/scsi/dmx3191d.c b/drivers/scsi/dmx3191d.c
index 5101328656b895feea0d960c48ddd59f542d9523..6e1960a88270e84fa065a50f76bfde5fc97b1c67 100644
--- a/drivers/scsi/dmx3191d.c
+++ b/drivers/scsi/dmx3191d.c
@@ -100,7 +100,7 @@ static int dmx3191d_probe_one(struct pci_dev *pdev,
 		 */
 		printk(KERN_WARNING "dmx3191: IRQ %d not available - "
 				    "switching to polled mode.\n", pdev->irq);
-		shost->irq = SCSI_IRQ_NONE;
+		shost->irq = NO_IRQ;
 	}
 
 	pci_set_drvdata(pdev, shost);
@@ -113,7 +113,8 @@ static int dmx3191d_probe_one(struct pci_dev *pdev,
 	return 0;
 
  out_free_irq:
-	free_irq(shost->irq, shost);
+	if (shost->irq != NO_IRQ)
+		free_irq(shost->irq, shost);
  out_release_region:
 	release_region(io, DMX3191D_REGION_LEN);
  out_disable_device:
@@ -130,7 +131,7 @@ static void dmx3191d_remove_one(struct pci_dev *pdev)
 
 	NCR5380_exit(shost);
 
-	if (shost->irq != SCSI_IRQ_NONE)
+	if (shost->irq != NO_IRQ)
 		free_irq(shost->irq, shost);
 	release_region(shost->io_port, DMX3191D_REGION_LEN);
 	pci_disable_device(pdev);
diff --git a/drivers/scsi/dtc.c b/drivers/scsi/dtc.c
index 43be785778d97754b625d293fe82a027939d3ca1..2971c7f0e89885023210ddccb3e28cd9c039a792 100644
--- a/drivers/scsi/dtc.c
+++ b/drivers/scsi/dtc.c
@@ -254,31 +254,35 @@ static int __init dtc_detect(struct scsi_host_template * tpnt)
 		else
 			instance->irq = NCR5380_probe_irq(instance, DTC_IRQS);
 
+		/* Compatibility with documented NCR5380 kernel parameters */
+		if (instance->irq == 255)
+			instance->irq = NO_IRQ;
+
 #ifndef DONT_USE_INTR
 		/* With interrupts enabled, it will sometimes hang when doing heavy
 		 * reads. So better not enable them until I finger it out. */
-		if (instance->irq != SCSI_IRQ_NONE)
+		if (instance->irq != NO_IRQ)
 			if (request_irq(instance->irq, dtc_intr, 0,
 					"dtc", instance)) {
 				printk(KERN_ERR "scsi%d : IRQ%d not free, interrupts disabled\n", instance->host_no, instance->irq);
-				instance->irq = SCSI_IRQ_NONE;
+				instance->irq = NO_IRQ;
 			}
 
-		if (instance->irq == SCSI_IRQ_NONE) {
+		if (instance->irq == NO_IRQ) {
 			printk(KERN_WARNING "scsi%d : interrupts not enabled. for better interactive performance,\n", instance->host_no);
 			printk(KERN_WARNING "scsi%d : please jumper the board for a free IRQ.\n", instance->host_no);
 		}
 #else
-		if (instance->irq != SCSI_IRQ_NONE)
+		if (instance->irq != NO_IRQ)
 			printk(KERN_WARNING "scsi%d : interrupts not used. Might as well not jumper it.\n", instance->host_no);
-		instance->irq = SCSI_IRQ_NONE;
+		instance->irq = NO_IRQ;
 #endif
 #if defined(DTCDEBUG) && (DTCDEBUG & DTCDEBUG_INIT)
 		printk("scsi%d : irq = %d\n", instance->host_no, instance->irq);
 #endif
 
 		printk(KERN_INFO "scsi%d : at 0x%05X", instance->host_no, (int) instance->base);
-		if (instance->irq == SCSI_IRQ_NONE)
+		if (instance->irq == NO_IRQ)
 			printk(" interrupts disabled");
 		else
 			printk(" irq %d", instance->irq);
@@ -350,7 +354,7 @@ static inline int NCR5380_pread(struct Scsi_Host *instance, unsigned char *dst,
 	i = 0;
 	NCR5380_read(RESET_PARITY_INTERRUPT_REG);
 	NCR5380_write(MODE_REG, MR_ENABLE_EOP_INTR | MR_DMA_MODE);
-	if (instance->irq == SCSI_IRQ_NONE)
+	if (instance->irq == NO_IRQ)
 		NCR5380_write(DTC_CONTROL_REG, CSR_DIR_READ);
 	else
 		NCR5380_write(DTC_CONTROL_REG, CSR_DIR_READ | CSR_INT_BASE);
@@ -401,7 +405,7 @@ static inline int NCR5380_pwrite(struct Scsi_Host *instance, unsigned char *src,
 	NCR5380_read(RESET_PARITY_INTERRUPT_REG);
 	NCR5380_write(MODE_REG, MR_ENABLE_EOP_INTR | MR_DMA_MODE);
 	/* set direction (write) */
-	if (instance->irq == SCSI_IRQ_NONE)
+	if (instance->irq == NO_IRQ)
 		NCR5380_write(DTC_CONTROL_REG, 0);
 	else
 		NCR5380_write(DTC_CONTROL_REG, CSR_5380_INTR);
@@ -440,7 +444,7 @@ static int dtc_release(struct Scsi_Host *shost)
 {
 	NCR5380_local_declare();
 	NCR5380_setup(shost);
-	if (shost->irq)
+	if (shost->irq != NO_IRQ)
 		free_irq(shost->irq, shost);
 	NCR5380_exit(shost);
 	if (shost->io_port && shost->n_io_port)
diff --git a/drivers/scsi/g_NCR5380.c b/drivers/scsi/g_NCR5380.c
index 151e1ad8fe9fc83261cf91b85a309e0b14238864..a2b70fb4c67f2e9a33dbeaa716ec94c216712feb 100644
--- a/drivers/scsi/g_NCR5380.c
+++ b/drivers/scsi/g_NCR5380.c
@@ -312,7 +312,7 @@ static int __init generic_NCR5380_detect(struct scsi_host_template *tpnt)
 			if (pnp_irq_valid(dev, 0))
 				overrides[count].irq = pnp_irq(dev, 0);
 			else
-				overrides[count].irq = SCSI_IRQ_NONE;
+				overrides[count].irq = NO_IRQ;
 			if (pnp_dma_valid(dev, 0))
 				overrides[count].dma = pnp_dma(dev, 0);
 			else
@@ -432,20 +432,24 @@ static int __init generic_NCR5380_detect(struct scsi_host_template *tpnt)
 		else
 			instance->irq = NCR5380_probe_irq(instance, 0xffff);
 
-		if (instance->irq != SCSI_IRQ_NONE)
+		/* Compatibility with documented NCR5380 kernel parameters */
+		if (instance->irq == 255)
+			instance->irq = NO_IRQ;
+
+		if (instance->irq != NO_IRQ)
 			if (request_irq(instance->irq, generic_NCR5380_intr,
 					0, "NCR5380", instance)) {
 				printk(KERN_WARNING "scsi%d : IRQ%d not free, interrupts disabled\n", instance->host_no, instance->irq);
-				instance->irq = SCSI_IRQ_NONE;
+				instance->irq = NO_IRQ;
 			}
 
-		if (instance->irq == SCSI_IRQ_NONE) {
+		if (instance->irq == NO_IRQ) {
 			printk(KERN_INFO "scsi%d : interrupts not enabled. for better interactive performance,\n", instance->host_no);
 			printk(KERN_INFO "scsi%d : please jumper the board for a free IRQ.\n", instance->host_no);
 		}
 
 		printk(KERN_INFO "scsi%d : at " STRVAL(NCR5380_map_name) " 0x%x", instance->host_no, (unsigned int) instance->NCR5380_instance_name);
-		if (instance->irq == SCSI_IRQ_NONE)
+		if (instance->irq == NO_IRQ)
 			printk(" interrupts disabled");
 		else
 			printk(" irq %d", instance->irq);
@@ -486,7 +490,7 @@ static int generic_NCR5380_release_resources(struct Scsi_Host *instance)
 	NCR5380_local_declare();
 	NCR5380_setup(instance);
 	
-	if (instance->irq != SCSI_IRQ_NONE)
+	if (instance->irq != NO_IRQ)
 		free_irq(instance->irq, instance);
 	NCR5380_exit(instance);
 
@@ -796,7 +800,7 @@ static int generic_NCR5380_show_info(struct seq_file *m, struct Scsi_Host *scsi_
 	PRINTP("NO NCR53C400 driver extensions\n");
 #endif
 	PRINTP("Using %s mapping at %s 0x%lx, " ANDP STRVAL(NCR5380_map_config) ANDP STRVAL(NCR5380_map_name) ANDP scsi_ptr->NCR5380_instance_name);
-	if (scsi_ptr->irq == SCSI_IRQ_NONE)
+	if (scsi_ptr->irq == NO_IRQ)
 		PRINTP("no interrupt\n");
 	else
 		PRINTP("on interrupt %d\n" ANDP scsi_ptr->irq);
diff --git a/drivers/scsi/mac_scsi.c b/drivers/scsi/mac_scsi.c
index 4dec06da3f34e86559295fc5ad2e41d961036f73..5d8d75c619cdb6963d51edc5bd0607883e152495 100644
--- a/drivers/scsi/mac_scsi.c
+++ b/drivers/scsi/mac_scsi.c
@@ -229,15 +229,15 @@ int __init macscsi_detect(struct scsi_host_template * tpnt)
 
     instance->n_io_port = 255;
 
-    if (instance->irq != SCSI_IRQ_NONE)
+    if (instance->irq != NO_IRQ)
 	if (request_irq(instance->irq, NCR5380_intr, 0, "ncr5380", instance)) {
 	    printk(KERN_WARNING "scsi%d: IRQ%d not free, interrupts disabled\n",
 		   instance->host_no, instance->irq);
-	    instance->irq = SCSI_IRQ_NONE;
+	    instance->irq = NO_IRQ;
 	}
 
     printk(KERN_INFO "scsi%d: generic 5380 at port %lX irq", instance->host_no, instance->io_port);
-    if (instance->irq == SCSI_IRQ_NONE)
+    if (instance->irq == NO_IRQ)
 	printk (KERN_INFO "s disabled");
     else
 	printk (KERN_INFO " %d", instance->irq);
@@ -252,7 +252,7 @@ int __init macscsi_detect(struct scsi_host_template * tpnt)
 
 int macscsi_release (struct Scsi_Host *shpnt)
 {
-	if (shpnt->irq != SCSI_IRQ_NONE)
+	if (shpnt->irq != NO_IRQ)
 		free_irq(shpnt->irq, shpnt);
 	NCR5380_exit(shpnt);
 
diff --git a/drivers/scsi/pas16.c b/drivers/scsi/pas16.c
index 3e40479ebb487359a8321304332299489743b895..3782091f82cba2e4885087e686e19b4da3adb193 100644
--- a/drivers/scsi/pas16.c
+++ b/drivers/scsi/pas16.c
@@ -62,13 +62,11 @@
  *   If you have problems with your card not being recognized, use
  *   the LILO command line override.  Try to get it recognized without
  *   interrupts.  Ie, for a board at the default 0x388 base port,
- *   boot: linux pas16=0x388,255
+ *   boot: linux pas16=0x388,0
  *
- *   SCSI_IRQ_NONE (255) should be specified for no interrupt,
+ *   NO_IRQ (0) should be specified for no interrupt,
  *   IRQ_AUTO (254) to autoprobe for an IRQ line if overridden
  *   on the command line.
- *
- *   (IRQ_AUTO == 254, SCSI_IRQ_NONE == 255 in NCR5380.h)
  */
  
 #include <linux/module.h>
@@ -416,15 +414,19 @@ static int __init pas16_detect(struct scsi_host_template *tpnt)
 	else 
 	    instance->irq = NCR5380_probe_irq(instance, PAS16_IRQS);
 
-	if (instance->irq != SCSI_IRQ_NONE) 
+	/* Compatibility with documented NCR5380 kernel parameters */
+	if (instance->irq == 255)
+		instance->irq = NO_IRQ;
+
+	if (instance->irq != NO_IRQ)
 	    if (request_irq(instance->irq, pas16_intr, 0,
 			    "pas16", instance)) {
 		printk("scsi%d : IRQ%d not free, interrupts disabled\n", 
 		    instance->host_no, instance->irq);
-		instance->irq = SCSI_IRQ_NONE;
+		instance->irq = NO_IRQ;
 	    } 
 
-	if (instance->irq == SCSI_IRQ_NONE) {
+	if (instance->irq == NO_IRQ) {
 	    printk("scsi%d : interrupts not enabled. for better interactive performance,\n", instance->host_no);
 	    printk("scsi%d : please jumper the board for a free IRQ.\n", instance->host_no);
 	    /* Disable 5380 interrupts, leave drive params the same */
@@ -438,7 +440,7 @@ static int __init pas16_detect(struct scsi_host_template *tpnt)
 
 	printk("scsi%d : at 0x%04x", instance->host_no, (int) 
 	    instance->io_port);
-	if (instance->irq == SCSI_IRQ_NONE)
+	if (instance->irq == NO_IRQ)
 	    printk (" interrupts disabled");
 	else 
 	    printk (" irq %d", instance->irq);
@@ -568,7 +570,7 @@ static inline int NCR5380_pwrite (struct Scsi_Host *instance, unsigned char *src
 
 static int pas16_release(struct Scsi_Host *shost)
 {
-	if (shost->irq)
+	if (shost->irq != NO_IRQ)
 		free_irq(shost->irq, shost);
 	NCR5380_exit(shost);
 	if (shost->io_port && shost->n_io_port)
diff --git a/drivers/scsi/sun3_scsi.c b/drivers/scsi/sun3_scsi.c
index 26b95dcb5e488ae5aecd233cf14c22f589cbb5f2..3e6386252953bdd698b08d7fc34c8a4777b1d395 100644
--- a/drivers/scsi/sun3_scsi.c
+++ b/drivers/scsi/sun3_scsi.c
@@ -278,7 +278,7 @@ static int __init sun3scsi_detect(struct scsi_host_template *tpnt)
 #ifndef REAL_DMA
 		printk("scsi%d: IRQ%d not free, interrupts disabled\n",
 		       instance->host_no, instance->irq);
-		instance->irq = SCSI_IRQ_NONE;
+		instance->irq = NO_IRQ;
 #else
 		printk("scsi%d: IRQ%d not free, bailing out\n",
 		       instance->host_no, instance->irq);
@@ -288,7 +288,7 @@ static int __init sun3scsi_detect(struct scsi_host_template *tpnt)
 	
 	pr_info("scsi%d: %s at port %lX irq", instance->host_no,
 		tpnt->proc_name, instance->io_port);
-	if (instance->irq == SCSI_IRQ_NONE)
+	if (instance->irq == NO_IRQ)
 		printk ("s disabled");
 	else
 		printk (" %d", instance->irq);
@@ -325,7 +325,7 @@ static int __init sun3scsi_detect(struct scsi_host_template *tpnt)
 
 static int sun3scsi_release(struct Scsi_Host *shpnt)
 {
-	if (shpnt->irq != SCSI_IRQ_NONE)
+	if (shpnt->irq != NO_IRQ)
 		free_irq(shpnt->irq, shpnt);
 
 	iounmap((void *)sun3_scsi_regp);
diff --git a/drivers/scsi/t128.c b/drivers/scsi/t128.c
index 6220dee8b697f0a30446b7ccda53ab3e4e0f8a26..ad833689b3110608ec1052e6129a2fb816810e20 100644
--- a/drivers/scsi/t128.c
+++ b/drivers/scsi/t128.c
@@ -228,15 +228,19 @@ static int __init t128_detect(struct scsi_host_template *tpnt)
 	else 
 	    instance->irq = NCR5380_probe_irq(instance, T128_IRQS);
 
-	if (instance->irq != SCSI_IRQ_NONE) 
+	/* Compatibility with documented NCR5380 kernel parameters */
+	if (instance->irq == 255)
+		instance->irq = NO_IRQ;
+
+	if (instance->irq != NO_IRQ)
 	    if (request_irq(instance->irq, t128_intr, 0, "t128",
 			    instance)) {
 		printk("scsi%d : IRQ%d not free, interrupts disabled\n", 
 		    instance->host_no, instance->irq);
-		instance->irq = SCSI_IRQ_NONE;
+		instance->irq = NO_IRQ;
 	    } 
 
-	if (instance->irq == SCSI_IRQ_NONE) {
+	if (instance->irq == NO_IRQ) {
 	    printk("scsi%d : interrupts not enabled. for better interactive performance,\n", instance->host_no);
 	    printk("scsi%d : please jumper the board for a free IRQ.\n", instance->host_no);
 	}
@@ -246,7 +250,7 @@ static int __init t128_detect(struct scsi_host_template *tpnt)
 #endif
 
 	printk("scsi%d : at 0x%08lx", instance->host_no, instance->base);
-	if (instance->irq == SCSI_IRQ_NONE)
+	if (instance->irq == NO_IRQ)
 	    printk (" interrupts disabled");
 	else 
 	    printk (" irq %d", instance->irq);
@@ -265,7 +269,7 @@ static int t128_release(struct Scsi_Host *shost)
 {
 	NCR5380_local_declare();
 	NCR5380_setup(shost);
-	if (shost->irq)
+	if (shost->irq != NO_IRQ)
 		free_irq(shost->irq, shost);
 	NCR5380_exit(shost);
 	if (shost->io_port && shost->n_io_port)