diff --git a/drivers/pnp/interface.c b/drivers/pnp/interface.c
index b09f67de13d091701b7c188cbff090dedb9c6630..7a9fb5544b80926f61644aaa883662c19adf3d8d 100644
--- a/drivers/pnp/interface.c
+++ b/drivers/pnp/interface.c
@@ -90,6 +90,8 @@ static void pnp_print_irq(pnp_info_buffer_t * buffer, char *space,
 		pnp_printf(buffer, " High-Level");
 	if (irq->flags & IORESOURCE_IRQ_LOWLEVEL)
 		pnp_printf(buffer, " Low-Level");
+	if (irq->flags & IORESOURCE_IRQ_OPTIONAL)
+		pnp_printf(buffer, " (optional)");
 	pnp_printf(buffer, "\n");
 }
 
diff --git a/drivers/pnp/manager.c b/drivers/pnp/manager.c
index 7ea9e1e28003f110bc6e86145be9e7a6de9bf2bf..a20accb5ef8fe16ce5486f6e9747ea5111a463e7 100644
--- a/drivers/pnp/manager.c
+++ b/drivers/pnp/manager.c
@@ -153,6 +153,15 @@ static int pnp_assign_irq(struct pnp_dev *dev, struct pnp_irq *rule, int idx)
 				goto __add;
 		}
 	}
+
+	if (rule->flags & IORESOURCE_IRQ_OPTIONAL) {
+		res->start = -1;
+		res->end = -1;
+		res->flags |= IORESOURCE_DISABLED;
+		dev_dbg(&dev->dev, "  irq %d disabled (optional)\n", idx);
+		goto __add;
+	}
+
 	dev_dbg(&dev->dev, "  couldn't assign irq %d\n", idx);
 	return -EBUSY;
 
diff --git a/drivers/pnp/quirks.c b/drivers/pnp/quirks.c
index 48e60171b3ba5ae870966b068b84afc7f3ce013e..e8515ce0d296abf29cff2402407ed0cf99d81781 100644
--- a/drivers/pnp/quirks.c
+++ b/drivers/pnp/quirks.c
@@ -121,34 +121,46 @@ static struct pnp_option *quirk_isapnp_mpu_options(struct pnp_dev *dev)
 	struct pnp_option *res;
 
 	/*
-	 * Build a functional IRQ-less variant of each MPU option.
+	 * Build a functional IRQ-optional variant of each MPU option.
 	 */
 
 	for (res = dev->dependent; res; res = res->next) {
 		struct pnp_option *curr;
 		struct pnp_port *port;
-		struct pnp_port *copy;
+		struct pnp_port *copy_port;
+		struct pnp_irq *irq;
+		struct pnp_irq *copy_irq;
 
 		port = res->port;
-		if (!port || !res->irq)
+		irq = res->irq;
+		if (!port || !irq)
 			continue;
 
-		copy = pnp_alloc(sizeof *copy);
-		if (!copy)
+		copy_port = pnp_alloc(sizeof *copy_port);
+		if (!copy_port)
+			break;
+
+		copy_irq = pnp_alloc(sizeof *copy_irq);
+		if (!copy_irq) {
+			kfree(copy_port);
 			break;
+		}
+
+		*copy_port = *port;
+		copy_port->next = NULL;
 
-		copy->min = port->min;
-		copy->max = port->max;
-		copy->align = port->align;
-		copy->size = port->size;
-		copy->flags = port->flags;
+		*copy_irq = *irq;
+		copy_irq->flags |= IORESOURCE_IRQ_OPTIONAL;
+		copy_irq->next = NULL;
 
 		curr = pnp_build_option(PNP_RES_PRIORITY_FUNCTIONAL);
 		if (!curr) {
-			kfree(copy);
+			kfree(copy_port);
+			kfree(copy_irq);
 			break;
 		}
-		curr->port = copy;
+		curr->port = copy_port;
+		curr->irq = copy_irq;
 
 		if (prev)
 			prev->next = curr;
@@ -157,7 +169,7 @@ static struct pnp_option *quirk_isapnp_mpu_options(struct pnp_dev *dev)
 		prev = curr;
 	}
 	if (head)
-		dev_info(&dev->dev, "adding IRQ-less MPU options\n");
+		dev_info(&dev->dev, "adding IRQ-optional MPU options\n");
 
 	return head;
 }
@@ -167,10 +179,6 @@ static void quirk_ad1815_mpu_resources(struct pnp_dev *dev)
 	struct pnp_option *res;
 	struct pnp_irq *irq;
 
-	/*
-	 * Distribute the independent IRQ over the dependent options
-	 */
-
 	res = dev->independent;
 	if (!res)
 		return;
@@ -179,33 +187,8 @@ static void quirk_ad1815_mpu_resources(struct pnp_dev *dev)
 	if (!irq || irq->next)
 		return;
 
-	res = dev->dependent;
-	if (!res)
-		return;
-
-	while (1) {
-		struct pnp_irq *copy;
-
-		copy = pnp_alloc(sizeof *copy);
-		if (!copy)
-			break;
-
-		bitmap_copy(copy->map.bits, irq->map.bits, PNP_IRQ_NR);
-		copy->flags = irq->flags;
-
-		copy->next = res->irq; /* Yes, this is NULL */
-		res->irq = copy;
-
-		if (!res->next)
-			break;
-		res = res->next;
-	}
-	kfree(irq);
-
-	res->next = quirk_isapnp_mpu_options(dev);
-
-	res = dev->independent;
-	res->irq = NULL;
+	irq->flags |= IORESOURCE_IRQ_OPTIONAL;
+	dev_info(&dev->dev, "made independent IRQ optional\n");
 }
 
 static void quirk_isapnp_mpu_resources(struct pnp_dev *dev)
diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 39db059ffb8b3c342210e544b4f76b4d5a33690e..2cd07cc29687c49bd1cf8a0883cf5c72bbb4e762 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -59,6 +59,7 @@ struct resource_list {
 #define IORESOURCE_IRQ_HIGHLEVEL	(1<<2)
 #define IORESOURCE_IRQ_LOWLEVEL		(1<<3)
 #define IORESOURCE_IRQ_SHAREABLE	(1<<4)
+#define IORESOURCE_IRQ_OPTIONAL 	(1<<5)
 
 /* PnP DMA specific bits (IORESOURCE_BITS) */
 #define IORESOURCE_DMA_TYPE_MASK	(3<<0)