ACPI / driver core: Store an ACPI device pointer in struct acpi_dev_node

Modify struct acpi_dev_node to contain a pointer to struct acpi_device
associated with the given device object (that is, its ACPI companion
device) instead of an ACPI handle corresponding to it.  Introduce two
new macros for manipulating that pointer in a CONFIG_ACPI-safe way,
ACPI_COMPANION() and ACPI_COMPANION_SET(), and rework the
ACPI_HANDLE() macro to take the above changes into account.
Drop the ACPI_HANDLE_SET() macro entirely and rework its users to
use ACPI_COMPANION_SET() instead.  For some of them who used to
pass the result of acpi_get_child() directly to ACPI_HANDLE_SET()
introduce a helper routine acpi_preset_companion() doing an
equivalent thing.

The main motivation for doing this is that there are things
represented by struct acpi_device objects that don't have valid
ACPI handles (so called fixed ACPI hardware features, such as
power and sleep buttons) and we would like to create platform
device objects for them and "glue" them to their ACPI companions
in the usual way (which currently is impossible due to the
lack of valid ACPI handles).  However, there are more reasons
why it may be useful.

First, struct acpi_device pointers allow of much better type checking
than void pointers which are ACPI handles, so it should be more
difficult to write buggy code using modified struct acpi_dev_node
and the new macros.  Second, the change should help to reduce (over
time) the number of places in which the result of ACPI_HANDLE() is
passed to acpi_bus_get_device() in order to obtain a pointer to the
struct acpi_device associated with the given "physical" device,
because now that pointer is returned by ACPI_COMPANION() directly.
Finally, the change should make it easier to write generic code that
will build both for CONFIG_ACPI set and unset without adding explicit
compiler directives to it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> # on Haswell
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com> # for ATA and SDIO part

22 files changed, 70 insertions, 68 deletions

diff --git a/arch/ia64/hp/common/sba_iommu.c b/arch/ia64/hp/common/sba_iommu.c
index d43daf192b2..4c530a82fc4 100644
--- a/arch/ia64/hp/common/sba_iommu.c
+++ b/arch/ia64/hp/common/sba_iommu.c
@@ -1992,7 +1992,7 @@ sba_connect_bus(struct pci_bus *bus)
 	if (PCI_CONTROLLER(bus)->iommu)
 		return;
 
-	handle = PCI_CONTROLLER(bus)->acpi_handle;
+	handle = acpi_device_handle(PCI_CONTROLLER(bus)->companion);
 	if (!handle)
 		return;
 
diff --git a/arch/ia64/include/asm/pci.h b/arch/ia64/include/asm/pci.h
index 80775f55f03..71fbaaa495c 100644
--- a/arch/ia64/include/asm/pci.h
+++ b/arch/ia64/include/asm/pci.h
@@ -95,7 +95,7 @@ struct iospace_resource {
 };
 
 struct pci_controller {
-	void *acpi_handle;
+	struct acpi_device *companion;
 	void *iommu;
 	int segment;
 	int node;		/* nearest node with memory or -1 for global allocation */
diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c
index 2326790b7d8..9e4938d8ca4 100644
--- a/arch/ia64/pci/pci.c
+++ b/arch/ia64/pci/pci.c
@@ -436,9 +436,9 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 	if (!controller)
 		return NULL;
 
-	controller->acpi_handle = device->handle;
+	controller->companion = device;
 
-	pxm = acpi_get_pxm(controller->acpi_handle);
+	pxm = acpi_get_pxm(device->handle);
 #ifdef CONFIG_NUMA
 	if (pxm >= 0)
 		controller->node = pxm_to_node(pxm);
@@ -489,7 +489,7 @@ int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
 {
 	struct pci_controller *controller = bridge->bus->sysdata;
 
-	ACPI_HANDLE_SET(&bridge->dev, controller->acpi_handle);
+	ACPI_COMPANION_SET(&bridge->dev, controller->companion);
 	return 0;
 }
 
diff --git a/arch/ia64/sn/kernel/io_acpi_init.c b/arch/ia64/sn/kernel/io_acpi_init.c
index b1725398b5a..0640739cc20 100644
--- a/arch/ia64/sn/kernel/io_acpi_init.c
+++ b/arch/ia64/sn/kernel/io_acpi_init.c
@@ -132,7 +132,7 @@ sn_get_bussoft_ptr(struct pci_bus *bus)
 	struct acpi_resource_vendor_typed *vendor;
 
 
-	handle = PCI_CONTROLLER(bus)->acpi_handle;
+	handle = acpi_device_handle(PCI_CONTROLLER(bus)->companion);
 	status = acpi_get_vendor_resource(handle, METHOD_NAME__CRS,
 					  &sn_uuid, &buffer);
 	if (ACPI_FAILURE(status)) {
@@ -360,7 +360,7 @@ sn_acpi_get_pcidev_info(struct pci_dev *dev, struct pcidev_info **pcidev_info,
 	acpi_status status;
 	struct acpi_buffer name_buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 
-	rootbus_handle = PCI_CONTROLLER(dev)->acpi_handle;
+	rootbus_handle = acpi_device_handle(PCI_CONTROLLER(dev)->companion);
         status = acpi_evaluate_integer(rootbus_handle, METHOD_NAME__SEG, NULL,
                                        &segment);
         if (ACPI_SUCCESS(status)) {
diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
index 7d7443283a9..947b5c417e8 100644
--- a/arch/x86/include/asm/pci.h
+++ b/arch/x86/include/asm/pci.h
@@ -15,7 +15,7 @@ struct pci_sysdata {
 	int		domain;		/* PCI domain */
 	int		node;		/* NUMA node */
 #ifdef CONFIG_ACPI
-	void		*acpi;		/* ACPI-specific data */
+	struct acpi_device *companion;	/* ACPI companion device */
 #endif
 #ifdef CONFIG_X86_64
 	void		*iommu;		/* IOMMU private data */
diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index 7fb24e53d4c..4f25ec07755 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -518,7 +518,7 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 	sd = &info->sd;
 	sd->domain = domain;
 	sd->node = node;
-	sd->acpi = device->handle;
+	sd->companion = device;
 	/*
 	 * Maybe the desired pci bus has been already scanned. In such case
 	 * it is unnecessary to scan the pci bus with the given domain,busnum.
@@ -589,7 +589,7 @@ int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
 {
 	struct pci_sysdata *sd = bridge->bus->sysdata;
 
-	ACPI_HANDLE_SET(&bridge->dev, sd->acpi);
+	ACPI_COMPANION_SET(&bridge->dev, sd->companion);
 	return 0;
 }
 
diff --git a/drivers/acpi/acpi_platform.c b/drivers/acpi/acpi_platform.c
index 8a4cfc7e71f..dbfe49e5fd6 100644
--- a/drivers/acpi/acpi_platform.c
+++ b/drivers/acpi/acpi_platform.c
@@ -111,7 +111,7 @@ int acpi_create_platform_device(struct acpi_device *adev,
 	pdevinfo.id = -1;
 	pdevinfo.res = resources;
 	pdevinfo.num_res = count;
-	pdevinfo.acpi_node.handle = adev->handle;
+	pdevinfo.acpi_node.companion = adev;
 	pdev = platform_device_register_full(&pdevinfo);
 	if (IS_ERR(pdev)) {
 		dev_err(&adev->dev, "platform device creation failed: %ld\n",
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index d42b2fb5a7e..119afda0968 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -22,16 +22,12 @@
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  */
 
-#include <linux/device.h>
+#include <linux/acpi.h>
 #include <linux/export.h>
 #include <linux/mutex.h>
 #include <linux/pm_qos.h>
 #include <linux/pm_runtime.h>
 
-#include <acpi/acpi.h>
-#include <acpi/acpi_bus.h>
-#include <acpi/acpi_drivers.h>
-
 #include "internal.h"
 
 #define _COMPONENT	ACPI_POWER_COMPONENT
diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c
index 10f0f40587b..782071fd3df 100644
--- a/drivers/acpi/glue.c
+++ b/drivers/acpi/glue.c
@@ -197,30 +197,27 @@ static void acpi_physnode_link_name(char *buf, unsigned int node_id)
 
 int acpi_bind_one(struct device *dev, acpi_handle handle)
 {
-	struct acpi_device *acpi_dev;
-	acpi_status status;
+	struct acpi_device *acpi_dev = NULL;
 	struct acpi_device_physical_node *physical_node, *pn;
 	char physical_node_name[PHYSICAL_NODE_NAME_SIZE];
 	struct list_head *physnode_list;
 	unsigned int node_id;
 	int retval = -EINVAL;
 
-	if (ACPI_HANDLE(dev)) {
+	if (ACPI_COMPANION(dev)) {
 		if (handle) {
-			dev_warn(dev, "ACPI handle is already set\n");
+			dev_warn(dev, "ACPI companion already set\n");
 			return -EINVAL;
 		} else {
-			handle = ACPI_HANDLE(dev);
+			acpi_dev = ACPI_COMPANION(dev);
 		}
+	} else {
+		acpi_bus_get_device(handle, &acpi_dev);
 	}
-	if (!handle)
+	if (!acpi_dev)
 		return -EINVAL;
 
 	get_device(dev);
-	status = acpi_bus_get_device(handle, &acpi_dev);
-	if (ACPI_FAILURE(status))
-		goto err;
-
 	physical_node = kzalloc(sizeof(*physical_node), GFP_KERNEL);
 	if (!physical_node) {
 		retval = -ENOMEM;
@@ -242,7 +239,7 @@ int acpi_bind_one(struct device *dev, acpi_handle handle)
 
 			dev_warn(dev, "Already associated with ACPI node\n");
 			kfree(physical_node);
-			if (ACPI_HANDLE(dev) != handle)
+			if (ACPI_COMPANION(dev) != acpi_dev)
 				goto err;
 
 			put_device(dev);
@@ -259,8 +256,8 @@ int acpi_bind_one(struct device *dev, acpi_handle handle)
 	list_add(&physical_node->node, physnode_list);
 	acpi_dev->physical_node_count++;
 
-	if (!ACPI_HANDLE(dev))
-		ACPI_HANDLE_SET(dev, acpi_dev->handle);
+	if (!ACPI_COMPANION(dev))
+		ACPI_COMPANION_SET(dev, acpi_dev);
 
 	acpi_physnode_link_name(physical_node_name, node_id);
 	retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
@@ -283,7 +280,7 @@ int acpi_bind_one(struct device *dev, acpi_handle handle)
 	return 0;
 
  err:
-	ACPI_HANDLE_SET(dev, NULL);
+	ACPI_COMPANION_SET(dev, NULL);
 	put_device(dev);
 	return retval;
 }
@@ -291,19 +288,12 @@ EXPORT_SYMBOL_GPL(acpi_bind_one);
 
 int acpi_unbind_one(struct device *dev)
 {
+	struct acpi_device *acpi_dev = ACPI_COMPANION(dev);
 	struct acpi_device_physical_node *entry;
-	struct acpi_device *acpi_dev;
-	acpi_status status;
 
-	if (!ACPI_HANDLE(dev))
+	if (!acpi_dev)
 		return 0;
 
-	status = acpi_bus_get_device(ACPI_HANDLE(dev), &acpi_dev);
-	if (ACPI_FAILURE(status)) {
-		dev_err(dev, "Oops, ACPI handle corrupt in %s()\n", __func__);
-		return -EINVAL;
-	}
-
 	mutex_lock(&acpi_dev->physical_node_lock);
 
 	list_for_each_entry(entry, &acpi_dev->physical_node_list, node)
@@ -316,7 +306,7 @@ int acpi_unbind_one(struct device *dev)
 			acpi_physnode_link_name(physnode_name, entry->node_id);
 			sysfs_remove_link(&acpi_dev->dev.kobj, physnode_name);
 			sysfs_remove_link(&dev->kobj, "firmware_node");
-			ACPI_HANDLE_SET(dev, NULL);
+			ACPI_COMPANION_SET(dev, NULL);
 			/* acpi_bind_one() increase refcnt by one. */
 			put_device(dev);
 			kfree(entry);
@@ -328,6 +318,15 @@ int acpi_unbind_one(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(acpi_unbind_one);
 
+void acpi_preset_companion(struct device *dev, acpi_handle parent, u64 addr)
+{
+	struct acpi_device *adev;
+
+	if (!acpi_bus_get_device(acpi_get_child(parent, addr), &adev))
+		ACPI_COMPANION_SET(dev, adev);
+}
+EXPORT_SYMBOL_GPL(acpi_preset_companion);
+
 static int acpi_platform_notify(struct device *dev)
 {
 	struct acpi_bus_type *type = acpi_get_bus_type(dev);
diff --git a/drivers/ata/libata-acpi.c b/drivers/ata/libata-acpi.c
index ab714d2ad97..4372cfa883c 100644
--- a/drivers/ata/libata-acpi.c
+++ b/drivers/ata/libata-acpi.c
@@ -185,7 +185,7 @@ void ata_acpi_bind_port(struct ata_port *ap)
 	if (libata_noacpi || ap->flags & ATA_FLAG_ACPI_SATA || !host_handle)
 		return;
 
-	ACPI_HANDLE_SET(&ap->tdev, acpi_get_child(host_handle, ap->port_no));
+	acpi_preset_companion(&ap->tdev, host_handle, ap->port_no);
 
 	if (ata_acpi_gtm(ap, &ap->__acpi_init_gtm) == 0)
 		ap->pflags |= ATA_PFLAG_INIT_GTM_VALID;
@@ -222,7 +222,7 @@ void ata_acpi_bind_dev(struct ata_device *dev)
 		parent_handle = port_handle;
 	}
 
-	ACPI_HANDLE_SET(&dev->tdev, acpi_get_child(parent_handle, adr));
+	acpi_preset_companion(&dev->tdev, parent_handle, adr);
 
 	register_hotplug_dock_device(ata_dev_acpi_handle(dev),
 				     &ata_acpi_dev_dock_ops, dev, NULL, NULL);
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 47051cd2511..3a94b799f16 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -432,7 +432,7 @@ struct platform_device *platform_device_register_full(
 		goto err_alloc;
 
 	pdev->dev.parent = pdevinfo->parent;
-	ACPI_HANDLE_SET(&pdev->dev, pdevinfo->acpi_node.handle);
+	ACPI_COMPANION_SET(&pdev->dev, pdevinfo->acpi_node.companion);
 
 	if (pdevinfo->dma_mask) {
 		/*
@@ -463,7 +463,7 @@ struct platform_device *platform_device_register_full(
 	ret = platform_device_add(pdev);
 	if (ret) {
 err:
-		ACPI_HANDLE_SET(&pdev->dev, NULL);
+		ACPI_COMPANION_SET(&pdev->dev, NULL);
 		kfree(pdev->dev.dma_mask);
 
 err_alloc:
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 7dd44615029..4e10b10d3dd 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -13,6 +13,7 @@
 #include <linux/acpi_gpio.h>
 #include <linux/idr.h>
 #include <linux/slab.h>
+#include <linux/acpi.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/gpio.h>
diff --git a/drivers/gpu/drm/radeon/radeon_atpx_handler.c b/drivers/gpu/drm/radeon/radeon_atpx_handler.c
index d96070bf838..27a6e9dbd0c 100644
--- a/drivers/gpu/drm/radeon/radeon_atpx_handler.c
+++ b/drivers/gpu/drm/radeon/radeon_atpx_handler.c
@@ -8,8 +8,7 @@
  */
 #include <linux/vga_switcheroo.h>
 #include <linux/slab.h>
-#include <acpi/acpi.h>
-#include <acpi/acpi_bus.h>
+#include <linux/acpi.h>
 #include <linux/pci.h>
 
 #include "radeon_acpi.h"
diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index fd7ce374f81..b7ecc3623a4 100644
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -1012,7 +1012,7 @@ static int i2c_hid_probe(struct i2c_client *client,
 	hid->hid_get_raw_report = i2c_hid_get_raw_report;
 	hid->hid_output_raw_report = i2c_hid_output_raw_report;
 	hid->dev.parent = &client->dev;
-	ACPI_HANDLE_SET(&hid->dev, ACPI_HANDLE(&client->dev));
+	ACPI_COMPANION_SET(&hid->dev, ACPI_COMPANION(&client->dev));
 	hid->bus = BUS_I2C;
 	hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
 	hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 75ba8608383..f74af33f5dd 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -674,7 +674,7 @@ i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info)
 	client->dev.bus = &i2c_bus_type;
 	client->dev.type = &i2c_client_type;
 	client->dev.of_node = info->of_node;
-	ACPI_HANDLE_SET(&client->dev, info->acpi_node.handle);
+	ACPI_COMPANION_SET(&client->dev, info->acpi_node.companion);
 
 	/* For 10-bit clients, add an arbitrary offset to avoid collisions */
 	dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap),
@@ -1103,7 +1103,7 @@ static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
 		return AE_OK;
 
 	memset(&info, 0, sizeof(info));
-	info.acpi_node.handle = handle;
+	info.acpi_node.companion = adev;
 	info.irq = -1;
 
 	INIT_LIST_HEAD(&resource_list);
diff --git a/drivers/ide/ide-acpi.c b/drivers/ide/ide-acpi.c
index 140c8ef5052..3662c4c536d 100644
--- a/drivers/ide/ide-acpi.c
+++ b/drivers/ide/ide-acpi.c
@@ -7,6 +7,7 @@
  * Copyright (C) 2006 Hannes Reinecke
  */
 
+#include <linux/acpi.h>
 #include <linux/ata.h>
 #include <linux/delay.h>
 #include <linux/device.h>
@@ -19,8 +20,6 @@
 #include <linux/dmi.h>
 #include <linux/module.h>
 
-#include <acpi/acpi_bus.h>
-
 #define REGS_PER_GTF		7
 
 struct GTM_buffer {
diff --git a/drivers/mmc/core/sdio_bus.c b/drivers/mmc/core/sdio_bus.c
index ef8956568c3..157b570ba34 100644
--- a/drivers/mmc/core/sdio_bus.c
+++ b/drivers/mmc/core/sdio_bus.c
@@ -308,8 +308,7 @@ static void sdio_acpi_set_handle(struct sdio_func *func)
 	struct mmc_host *host = func->card->host;
 	u64 addr = (host->slotno << 16) | func->num;
 
-	ACPI_HANDLE_SET(&func->dev,
-			acpi_get_child(ACPI_HANDLE(host->parent), addr));
+	acpi_preset_companion(&func->dev, ACPI_HANDLE(host->parent), addr);
 }
 #else
 static inline void sdio_acpi_set_handle(struct sdio_func *func) {}
diff --git a/drivers/pci/hotplug/sgi_hotplug.c b/drivers/pci/hotplug/sgi_hotplug.c
index b2781dfe60e..5b05a68cca6 100644
--- a/drivers/pci/hotplug/sgi_hotplug.c
+++ b/drivers/pci/hotplug/sgi_hotplug.c
@@ -9,6 +9,7 @@
  * Work to add BIOS PROM support was completed by Mike Habeck.
  */
 
+#include <linux/acpi.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -29,7 +30,6 @@
 #include <asm/sn/sn_feature_sets.h>
 #include <asm/sn/sn_sal.h>
 #include <asm/sn/types.h>
-#include <linux/acpi.h>
 #include <asm/sn/acpi.h>
 
 #include "../pci.h"
@@ -414,7 +414,7 @@ static int enable_slot(struct hotplug_slot *bss_hotplug_slot)
 		acpi_handle rethandle;
 		acpi_status ret;
 
-		phandle = PCI_CONTROLLER(slot->pci_bus)->acpi_handle;
+		phandle = acpi_device_handle(PCI_CONTROLLER(slot->pci_bus)->companion);
 
 		if (acpi_bus_get_device(phandle, &pdevice)) {
 			dev_dbg(&slot->pci_bus->self->dev,
@@ -495,7 +495,7 @@ static int disable_slot(struct hotplug_slot *bss_hotplug_slot)
 
 	/* free the ACPI resources for the slot */
 	if (SN_ACPI_BASE_SUPPORT() &&
-            PCI_CONTROLLER(slot->pci_bus)->acpi_handle) {
+            PCI_CONTROLLER(slot->pci_bus)->companion) {
 		unsigned long long adr;
 		struct acpi_device *device;
 		acpi_handle phandle;
@@ -504,7 +504,7 @@ static int disable_slot(struct hotplug_slot *bss_hotplug_slot)
 		acpi_status ret;
 
 		/* Get the rootbus node pointer */
-		phandle = PCI_CONTROLLER(slot->pci_bus)->acpi_handle;
+		phandle = acpi_device_handle(PCI_CONTROLLER(slot->pci_bus)->companion);
 
 		acpi_scan_lock_acquire();
 		/*
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 927998aa5e7..a968d8549ee 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1144,7 +1144,7 @@ static acpi_status acpi_spi_add_device(acpi_handle handle, u32 level,
 		return AE_NO_MEMORY;
 	}
 
-	ACPI_HANDLE_SET(&spi->dev, handle);
+	ACPI_COMPANION_SET(&spi->dev, adev);
 	spi->irq = -1;
 
 	INIT_LIST_HEAD(&resource_list);
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 89c60b0f640..7b2de026a4f 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -431,9 +431,9 @@ static inline acpi_handle acpi_get_child(acpi_handle handle, u64 addr)
 {
 	return acpi_find_child(handle, addr, false);
 }
+void acpi_preset_companion(struct device *dev, acpi_handle parent, u64 addr);
 int acpi_is_root_bridge(acpi_handle);
 struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle);
-#define DEVICE_ACPI_HANDLE(dev) ((acpi_handle)ACPI_HANDLE(dev))
 
 int acpi_enable_wakeup_device_power(struct acpi_device *dev, int state);
 int acpi_disable_wakeup_device_power(struct acpi_device *dev);
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index b0972c4ce81..47369aadb1d 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -44,6 +44,15 @@
 #include <acpi/acpi_numa.h>
 #include <asm/acpi.h>
 
+static inline acpi_handle acpi_device_handle(struct acpi_device *adev)
+{
+	return adev ? adev->handle : NULL;
+}
+
+#define ACPI_COMPANION(dev)		((dev)->acpi_node.companion)
+#define ACPI_COMPANION_SET(dev, adev)	ACPI_COMPANION(dev) = (adev)
+#define ACPI_HANDLE(dev)		acpi_device_handle(ACPI_COMPANION(dev))
+
 enum acpi_irq_model_id {
 	ACPI_IRQ_MODEL_PIC = 0,
 	ACPI_IRQ_MODEL_IOAPIC,
@@ -401,6 +410,10 @@ static inline bool acpi_driver_match_device(struct device *dev,
 
 #define acpi_disabled 1
 
+#define ACPI_COMPANION(dev)		(NULL)
+#define ACPI_COMPANION_SET(dev, adev)	do { } while (0)
+#define ACPI_HANDLE(dev)		(NULL)
+
 static inline void acpi_early_init(void) { }
 
 static inline int early_acpi_boot_init(void)
@@ -469,6 +482,8 @@ static inline bool acpi_driver_match_device(struct device *dev,
 
 #endif	/* !CONFIG_ACPI */
 
+#define DEVICE_ACPI_HANDLE(dev)	ACPI_HANDLE(dev)
+
 #ifdef CONFIG_ACPI
 void acpi_os_set_prepare_sleep(int (*func)(u8 sleep_state,
 			       u32 pm1a_ctrl,  u32 pm1b_ctrl));
diff --git a/include/linux/device.h b/include/linux/device.h
index b025925df7f..952b01033c3 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -644,9 +644,11 @@ struct device_dma_parameters {
 	unsigned long segment_boundary_mask;
 };
 
+struct acpi_device;
+
 struct acpi_dev_node {
 #ifdef CONFIG_ACPI
-	void	*handle;
+	struct acpi_device *companion;
 #endif
 };
 
@@ -790,14 +792,6 @@ static inline struct device *kobj_to_dev(struct kobject *kobj)
 	return container_of(kobj, struct device, kobj);
 }
 
-#ifdef CONFIG_ACPI
-#define ACPI_HANDLE(dev)	((dev)->acpi_node.handle)
-#define ACPI_HANDLE_SET(dev, _handle_)	(dev)->acpi_node.handle = (_handle_)
-#else
-#define ACPI_HANDLE(dev)	(NULL)
-#define ACPI_HANDLE_SET(dev, _handle_)	do { } while (0)
-#endif
-
 /* Get the wakeup routines, which depend on struct device */
 #include <linux/pm_wakeup.h>