driver core / ACPI: Represent ACPI companions using fwnode_handle

Now that we have struct fwnode_handle, we can use that to point to
ACPI companions from struct device objects instead of pointing to
struct acpi_device directly.

There are two benefits from that.  First, the somewhat ugly and
hackish struct acpi_dev_node can be dropped and, second, the same
struct fwnode_handle pointer can be used in the future to point
to other (non-ACPI) firmware device node types.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Grant Likely <grant.likely@linaro.org>

drivers/acpi/acpi_platform.c

@@ -102,7 +102,7 @@ struct platform_device *acpi_create_platform_device(struct acpi_device *adev)
 	pdevinfo.id = -1;
 	pdevinfo.res = resources;
 	pdevinfo.num_res = count;
-	pdevinfo.acpi_node.companion = adev;
+	pdevinfo.fwnode = acpi_fwnode_handle(adev);
 	pdevinfo.dma_mask = DMA_BIT_MASK(32);
 	pdev = platform_device_register_full(&pdevinfo);
 	if (IS_ERR(pdev))

drivers/acpi/dock.c

@@ -615,7 +615,7 @@ void acpi_dock_add(struct acpi_device *adev)
 	memset(&pdevinfo, 0, sizeof(pdevinfo));
 	pdevinfo.name = "dock";
 	pdevinfo.id = dock_station_count;
-	pdevinfo.acpi_node.companion = adev;
+	pdevinfo.fwnode = acpi_fwnode_handle(adev);
 	pdevinfo.data = &ds;
 	pdevinfo.size_data = sizeof(ds);
 	dd = platform_device_register_full(&pdevinfo);

drivers/base/platform.c

@@ -454,7 +454,7 @@ struct platform_device *platform_device_register_full(
 		goto err_alloc;
 
 	pdev->dev.parent = pdevinfo->parent;
-	ACPI_COMPANION_SET(&pdev->dev, pdevinfo->acpi_node.companion);
+	pdev->dev.fwnode = pdevinfo->fwnode;
 
 	if (pdevinfo->dma_mask) {
 		/*

drivers/gpio/gpiolib.h

@@ -17,6 +17,8 @@
 
 enum of_gpio_flags;
 
+struct acpi_device;
+
 /**
  * struct acpi_gpio_info - ACPI GPIO specific information
  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo

drivers/i2c/i2c-core.c

@@ -133,7 +133,7 @@ static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
 		return AE_OK;
 
 	memset(&info, 0, sizeof(info));
-	info.acpi_node.companion = adev;
+	info.fwnode = acpi_fwnode_handle(adev);
 	info.irq = -1;
 
 	INIT_LIST_HEAD(&resource_list);
@@ -971,7 +971,7 @@ 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_COMPANION_SET(&client->dev, info->acpi_node.companion);
+	client->dev.fwnode = info->fwnode;
 
 	i2c_dev_set_name(adap, client);
 	status = device_register(&client->dev);

include/acpi/acpi_bus.h

@@ -386,7 +386,8 @@ static inline bool is_acpi_node(struct fwnode_handle *fwnode)
 
 static inline struct acpi_device *acpi_node(struct fwnode_handle *fwnode)
 {
-	return fwnode ? container_of(fwnode, struct acpi_device, fwnode) : NULL;
+	return is_acpi_node(fwnode) ?
+		container_of(fwnode, struct acpi_device, fwnode) : NULL;
 }
 
 static inline struct fwnode_handle *acpi_fwnode_handle(struct acpi_device *adev)

include/linux/acpi.h

@@ -53,8 +53,9 @@ 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_COMPANION(dev)		acpi_node((dev)->fwnode)
+#define ACPI_COMPANION_SET(dev, adev)	(dev)->fwnode = (adev) ? \
+	acpi_fwnode_handle(adev) : NULL
 #define ACPI_HANDLE(dev)		acpi_device_handle(ACPI_COMPANION(dev))
 
 static inline void acpi_preset_companion(struct device *dev,

include/linux/device.h

@@ -38,6 +38,7 @@ struct class;
 struct subsys_private;
 struct bus_type;
 struct device_node;
+struct fwnode_handle;
 struct iommu_ops;
 struct iommu_group;
 
@@ -650,14 +651,6 @@ struct device_dma_parameters {
 	unsigned long segment_boundary_mask;
 };
 
-struct acpi_device;
-
-struct acpi_dev_node {
-#ifdef CONFIG_ACPI
-	struct acpi_device *companion;
-#endif
-};
-
 /**
  * struct device - The basic device structure
  * @parent:	The device's "parent" device, the device to which it is attached.
@@ -703,7 +696,7 @@ struct acpi_dev_node {
  * @cma_area:	Contiguous memory area for dma allocations
  * @archdata:	For arch-specific additions.
  * @of_node:	Associated device tree node.
- * @acpi_node:	Associated ACPI device node.
+ * @fwnode:	Associated device node supplied by platform firmware.
  * @devt:	For creating the sysfs "dev".
  * @id:		device instance
  * @devres_lock: Spinlock to protect the resource of the device.
@@ -779,7 +772,7 @@ struct device {
 	struct dev_archdata	archdata;
 
 	struct device_node	*of_node; /* associated device tree node */
-	struct acpi_dev_node	acpi_node; /* associated ACPI device node */
+	struct fwnode_handle	*fwnode; /* firmware device node */
 
 	dev_t			devt;	/* dev_t, creates the sysfs "dev" */
 	u32			id;	/* device instance */

include/linux/fwnode.h

@@ -0,0 +1,25 @@
+/*
+ * fwnode.h - Firmware device node object handle type definition.
+ *
+ * Copyright (C) 2015, Intel Corporation
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * 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.
+ */
+
+#ifndef _LINUX_FWNODE_H_
+#define _LINUX_FWNODE_H_
+
+enum fwnode_type {
+	FWNODE_INVALID = 0,
+	FWNODE_OF,
+	FWNODE_ACPI,
+};
+
+struct fwnode_handle {
+	enum fwnode_type type;
+};
+
+#endif

include/linux/i2c.h

@@ -278,7 +278,7 @@ static inline int i2c_slave_event(struct i2c_client *client,
  * @platform_data: stored in i2c_client.dev.platform_data
  * @archdata: copied into i2c_client.dev.archdata
  * @of_node: pointer to OpenFirmware device node
- * @acpi_node: ACPI device node
+ * @fwnode: device node supplied by the platform firmware
  * @irq: stored in i2c_client.irq
  *
  * I2C doesn't actually support hardware probing, although controllers and
@@ -299,7 +299,7 @@ struct i2c_board_info {
 	void		*platform_data;
 	struct dev_archdata	*archdata;
 	struct device_node *of_node;
-	struct acpi_dev_node acpi_node;
+	struct fwnode_handle *fwnode;
 	int		irq;
 };
 

include/linux/platform_device.h

@@ -59,7 +59,7 @@ extern int platform_add_devices(struct platform_device **, int);
 
 struct platform_device_info {
 		struct device *parent;
-		struct acpi_dev_node acpi_node;
+		struct fwnode_handle *fwnode;
 
 		const char *name;
 		int id;

include/linux/property.h

@@ -13,6 +13,7 @@
 #ifndef _LINUX_PROPERTY_H_
 #define _LINUX_PROPERTY_H_
 
+#include <linux/fwnode.h>
 #include <linux/types.h>
 
 struct device;
@@ -40,16 +41,6 @@ int device_property_read_string_array(struct device *dev, const char *propname,
 int device_property_read_string(struct device *dev, const char *propname,
 				const char **val);
 
-enum fwnode_type {
-	FWNODE_INVALID = 0,
-	FWNODE_OF,
-	FWNODE_ACPI,
-};
-
-struct fwnode_handle {
-	enum fwnode_type type;
-};
-
 bool fwnode_property_present(struct fwnode_handle *fwnode, const char *propname);
 int fwnode_property_read_u8_array(struct fwnode_handle *fwnode,
 				  const char *propname, u8 *val,