diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index fdc864f..d7d28ae 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -69,3 +69,10 @@
 	  physical resources.
 
 	  If unsure, say N.
+
+config PCI_IOAPIC
+	bool
+	depends on PCI
+	depends on ACPI
+	depends on HOTPLUG
+	default y
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index 4a7f11d..4df48d5 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -14,6 +14,8 @@
 # Build PCI Express stuff if needed
 obj-$(CONFIG_PCIEPORTBUS) += pcie/
 
+obj-$(CONFIG_PCI_IOAPIC) += ioapic.o
+
 obj-$(CONFIG_HOTPLUG) += hotplug.o
 
 # Build the PCI Hotplug drivers if we were asked to
diff --git a/drivers/pci/hotplug/acpiphp.h b/drivers/pci/hotplug/acpiphp.h
index 7d938df..bab5204 100644
--- a/drivers/pci/hotplug/acpiphp.h
+++ b/drivers/pci/hotplug/acpiphp.h
@@ -146,12 +146,6 @@
 	struct module *owner;
 };
 
-struct acpiphp_ioapic {
-	struct pci_dev *dev;
-	u32 gsi_base;
-	struct list_head list;
-};
-
 /* PCI bus bridge HID */
 #define ACPI_PCI_HOST_HID		"PNP0A03"
 
diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index 58d25a1..392e4b3 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -52,8 +52,6 @@
 #include "acpiphp.h"
 
 static LIST_HEAD(bridge_list);
-static LIST_HEAD(ioapic_list);
-static DEFINE_SPINLOCK(ioapic_list_lock);
 
 #define MY_NAME "acpiphp_glue"
 
@@ -606,190 +604,6 @@
 					   handle_hotplug_event_bridge);
 }
 
-static struct pci_dev * get_apic_pci_info(acpi_handle handle)
-{
-	struct pci_dev *dev;
-
-	dev = acpi_get_pci_dev(handle);
-	if (!dev)
-		return NULL;
-
-	if ((dev->class != PCI_CLASS_SYSTEM_PIC_IOAPIC) &&
-	    (dev->class != PCI_CLASS_SYSTEM_PIC_IOXAPIC))
-	{
-		pci_dev_put(dev);
-		return NULL;
-	}
-
-	return dev;
-}
-
-static int get_gsi_base(acpi_handle handle, u32 *gsi_base)
-{
-	acpi_status status;
-	int result = -1;
-	unsigned long long gsb;
-	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
-	union acpi_object *obj;
-	void *table;
-
-	status = acpi_evaluate_integer(handle, "_GSB", NULL, &gsb);
-	if (ACPI_SUCCESS(status)) {
-		*gsi_base = (u32)gsb;
-		return 0;
-	}
-
-	status = acpi_evaluate_object(handle, "_MAT", NULL, &buffer);
-	if (ACPI_FAILURE(status) || !buffer.length || !buffer.pointer)
-		return -1;
-
-	obj = buffer.pointer;
-	if (obj->type != ACPI_TYPE_BUFFER)
-		goto out;
-
-	table = obj->buffer.pointer;
-	switch (((struct acpi_subtable_header *)table)->type) {
-	case ACPI_MADT_TYPE_IO_SAPIC:
-		*gsi_base = ((struct acpi_madt_io_sapic *)table)->global_irq_base;
-		result = 0;
-		break;
-	case ACPI_MADT_TYPE_IO_APIC:
-		*gsi_base = ((struct acpi_madt_io_apic *)table)->global_irq_base;
-		result = 0;
-		break;
-	default:
-		break;
-	}
- out:
-	kfree(buffer.pointer);
-	return result;
-}
-
-static acpi_status
-ioapic_add(acpi_handle handle, u32 lvl, void *context, void **rv)
-{
-	acpi_status status;
-	unsigned long long sta;
-	acpi_handle tmp;
-	struct pci_dev *pdev;
-	u32 gsi_base;
-	u64 phys_addr;
-	struct acpiphp_ioapic *ioapic;
-
-	/* Evaluate _STA if present */
-	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
-	if (ACPI_SUCCESS(status) && sta != ACPI_STA_ALL)
-		return AE_CTRL_DEPTH;
-
-	/* Scan only PCI bus scope */
-	status = acpi_get_handle(handle, "_HID", &tmp);
-	if (ACPI_SUCCESS(status))
-		return AE_CTRL_DEPTH;
-
-	if (get_gsi_base(handle, &gsi_base))
-		return AE_OK;
-
-	ioapic = kmalloc(sizeof(*ioapic), GFP_KERNEL);
-	if (!ioapic)
-		return AE_NO_MEMORY;
-
-	pdev = get_apic_pci_info(handle);
-	if (!pdev)
-		goto exit_kfree;
-
-	if (pci_enable_device(pdev))
-		goto exit_pci_dev_put;
-
-	pci_set_master(pdev);
-
-	if (pci_request_region(pdev, 0, "I/O APIC(acpiphp)"))
-		goto exit_pci_disable_device;
-
-	phys_addr = pci_resource_start(pdev, 0);
-	if (acpi_register_ioapic(handle, phys_addr, gsi_base))
-		goto exit_pci_release_region;
-
-	ioapic->gsi_base = gsi_base;
-	ioapic->dev = pdev;
-	spin_lock(&ioapic_list_lock);
-	list_add_tail(&ioapic->list, &ioapic_list);
-	spin_unlock(&ioapic_list_lock);
-
-	return AE_OK;
-
- exit_pci_release_region:
-	pci_release_region(pdev, 0);
- exit_pci_disable_device:
-	pci_disable_device(pdev);
- exit_pci_dev_put:
-	pci_dev_put(pdev);
- exit_kfree:
-	kfree(ioapic);
-
-	return AE_OK;
-}
-
-static acpi_status
-ioapic_remove(acpi_handle handle, u32 lvl, void *context, void **rv)
-{
-	acpi_status status;
-	unsigned long long sta;
-	acpi_handle tmp;
-	u32 gsi_base;
-	struct acpiphp_ioapic *pos, *n, *ioapic = NULL;
-
-	/* Evaluate _STA if present */
-	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
-	if (ACPI_SUCCESS(status) && sta != ACPI_STA_ALL)
-		return AE_CTRL_DEPTH;
-
-	/* Scan only PCI bus scope */
-	status = acpi_get_handle(handle, "_HID", &tmp);
-	if (ACPI_SUCCESS(status))
-		return AE_CTRL_DEPTH;
-
-	if (get_gsi_base(handle, &gsi_base))
-		return AE_OK;
-
-	acpi_unregister_ioapic(handle, gsi_base);
-
-	spin_lock(&ioapic_list_lock);
-	list_for_each_entry_safe(pos, n, &ioapic_list, list) {
-		if (pos->gsi_base != gsi_base)
-			continue;
-		ioapic = pos;
-		list_del(&ioapic->list);
-		break;
-	}
-	spin_unlock(&ioapic_list_lock);
-
-	if (!ioapic)
-		return AE_OK;
-
-	pci_release_region(ioapic->dev, 0);
-	pci_disable_device(ioapic->dev);
-	pci_dev_put(ioapic->dev);
-	kfree(ioapic);
-
-	return AE_OK;
-}
-
-static int acpiphp_configure_ioapics(acpi_handle handle)
-{
-	ioapic_add(handle, 0, NULL, NULL);
-	acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
-			    ACPI_UINT32_MAX, ioapic_add, NULL, NULL);
-	return 0;
-}
-
-static int acpiphp_unconfigure_ioapics(acpi_handle handle)
-{
-	ioapic_remove(handle, 0, NULL, NULL);
-	acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
-			    ACPI_UINT32_MAX, ioapic_remove, NULL, NULL);
-	return 0;
-}
-
 static int power_on_slot(struct acpiphp_slot *slot)
 {
 	acpi_status status;
@@ -1014,8 +828,6 @@
 	pci_bus_assign_resources(bus);
 	acpiphp_sanitize_bus(bus);
 	acpiphp_set_hpp_values(bus);
-	list_for_each_entry(func, &slot->funcs, sibling)
-		acpiphp_configure_ioapics(func->handle);
 	pci_enable_bridges(bus);
 	pci_bus_add_devices(bus);
 
@@ -1091,7 +903,6 @@
 	}
 
 	list_for_each_entry(func, &slot->funcs, sibling) {
-		acpiphp_unconfigure_ioapics(func->handle);
 		acpiphp_bus_trim(func->handle);
 	}
 
@@ -1275,7 +1086,6 @@
 	acpiphp_sanitize_bus(bus);
 	acpiphp_set_hpp_values(bus);
 	pci_enable_bridges(bus);
-	acpiphp_configure_ioapics(handle);
 	return 0;
 }
 
diff --git a/drivers/pci/ioapic.c b/drivers/pci/ioapic.c
new file mode 100644
index 0000000..3e0d7b5
--- /dev/null
+++ b/drivers/pci/ioapic.c
@@ -0,0 +1,127 @@
+/*
+ * IOAPIC/IOxAPIC/IOSAPIC driver
+ *
+ * Copyright (C) 2009 Fujitsu Limited.
+ * (c) Copyright 2009 Hewlett-Packard Development Company, L.P.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ * This driver manages PCI I/O APICs added by hotplug after boot.  We try to
+ * claim all I/O APIC PCI devices, but those present at boot were registered
+ * when we parsed the ACPI MADT, so we'll fail when we try to re-register
+ * them.
+ */
+
+#include <linux/pci.h>
+#include <linux/acpi.h>
+#include <acpi/acpi_bus.h>
+
+struct ioapic {
+	acpi_handle	handle;
+	u32		gsi_base;
+};
+
+static int ioapic_probe(struct pci_dev *dev, const struct pci_device_id *ent)
+{
+	acpi_handle handle;
+	acpi_status status;
+	unsigned long long gsb;
+	struct ioapic *ioapic;
+	u64 addr;
+	int ret;
+	char *type;
+
+	handle = DEVICE_ACPI_HANDLE(&dev->dev);
+	if (!handle)
+		return -EINVAL;
+
+	status = acpi_evaluate_integer(handle, "_GSB", NULL, &gsb);
+	if (ACPI_FAILURE(status))
+		return -EINVAL;
+
+	/*
+	 * The previous code in acpiphp evaluated _MAT if _GSB failed, but
+	 * ACPI spec 4.0 sec 6.2.2 requires _GSB for hot-pluggable I/O APICs.
+	 */
+
+	ioapic = kzalloc(sizeof(*ioapic), GFP_KERNEL);
+	if (!ioapic)
+		return -ENOMEM;
+
+	ioapic->handle = handle;
+	ioapic->gsi_base = (u32) gsb;
+
+	if (dev->class == PCI_CLASS_SYSTEM_PIC_IOAPIC)
+		type = "IOAPIC";
+	else
+		type = "IOxAPIC";
+
+	ret = pci_enable_device(dev);
+	if (ret < 0)
+		goto exit_free;
+
+	pci_set_master(dev);
+
+	if (pci_request_region(dev, 0, type))
+		goto exit_disable;
+
+	addr = pci_resource_start(dev, 0);
+	if (acpi_register_ioapic(ioapic->handle, addr, ioapic->gsi_base))
+		goto exit_release;
+
+	pci_set_drvdata(dev, ioapic);
+	dev_info(&dev->dev, "%s at %#llx, GSI %u\n", type, addr,
+		 ioapic->gsi_base);
+	return 0;
+
+exit_release:
+	pci_release_region(dev, 0);
+exit_disable:
+	pci_disable_device(dev);
+exit_free:
+	kfree(ioapic);
+	return -ENODEV;
+}
+
+static void ioapic_remove(struct pci_dev *dev)
+{
+	struct ioapic *ioapic = pci_get_drvdata(dev);
+
+	acpi_unregister_ioapic(ioapic->handle, ioapic->gsi_base);
+	pci_release_region(dev, 0);
+	pci_disable_device(dev);
+	kfree(ioapic);
+}
+
+
+static struct pci_device_id ioapic_devices[] = {
+	{ PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
+	  PCI_CLASS_SYSTEM_PIC_IOAPIC << 8, 0xffff00, },
+	{ PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
+	  PCI_CLASS_SYSTEM_PIC_IOXAPIC << 8, 0xffff00, },
+	{ }
+};
+
+static struct pci_driver ioapic_driver = {
+	.name		= "ioapic",
+	.id_table	= ioapic_devices,
+	.probe		= ioapic_probe,
+	.remove		= __devexit_p(ioapic_remove),
+};
+
+static int __init ioapic_init(void)
+{
+	return pci_register_driver(&ioapic_driver);
+}
+
+static void __exit ioapic_exit(void)
+{
+	pci_unregister_driver(&ioapic_driver);
+}
+
+module_init(ioapic_init);
+module_exit(ioapic_exit);