[ACPI] Bind PCI devices with ACPI devices

Implement the framework for binding physical devices
with ACPI devices. A physical bus like PCI bus
should create a 'acpi_bus_type', with:

.find_device:
For device which has parent such as normal PCI devices.

.find_bridge:
It's for special devices, such as PCI root bridge
or IDE controller. Such devices generally haven't a
parent or ->bus. We use the special method
to get an ACPI handle.

Uses new field in struct device: firmware_data

http://bugzilla.kernel.org/show_bug.cgi?id=4277

Signed-off-by: David Shaohua Li <[e-mail]>
Signed-off-by: Len Brown <[e-mail]>

drivers/acpi/Makefile

···
 endif
 
 obj-$(CONFIG_ACPI_BUS)		+= sleep/
-obj-$(CONFIG_ACPI_BUS)		+= bus.o
+obj-$(CONFIG_ACPI_BUS)		+= bus.o glue.o
 obj-$(CONFIG_ACPI_AC) 		+= ac.o
 obj-$(CONFIG_ACPI_BATTERY)	+= battery.o
 obj-$(CONFIG_ACPI_BUTTON)	+= button.o

drivers/acpi/glue.c

···
+/*
+ * Link physical devices with ACPI devices support
+ *
+ * Copyright (c) 2005 David Shaohua Li <[e-mail]>
+ * Copyright (c) 2005 Intel Corp.
+ *
+ * This file is released under the GPLv2.
+ */
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/device.h>
+#include <linux/rwsem.h>
+#include <linux/acpi.h>
+
+#define ACPI_GLUE_DEBUG	0
+#if ACPI_GLUE_DEBUG
+#define DBG(x...) printk(PREFIX x)
+#else
+#define DBG(x...)
+#endif
+static LIST_HEAD(bus_type_list);
+static DECLARE_RWSEM(bus_type_sem);
+
+int register_acpi_bus_type(struct acpi_bus_type *type)
+{
+	if (acpi_disabled)
+		return -ENODEV;
+	if (type && type->bus && type->find_device) {
+		down_write(&bus_type_sem);
+		list_add_tail(&type->list, &bus_type_list);
+		up_write(&bus_type_sem);
+		DBG("ACPI bus type %s registered\n", type->bus->name);
+		return 0;
+	}
+	return -ENODEV;
+}
+
+EXPORT_SYMBOL(register_acpi_bus_type);
+
+int unregister_acpi_bus_type(struct acpi_bus_type *type)
+{
+	if (acpi_disabled)
+		return 0;
+	if (type) {
+		down_write(&bus_type_sem);
+		list_del_init(&type->list);
+		up_write(&bus_type_sem);
+		DBG("ACPI bus type %s unregistered\n", type->bus->name);
+		return 0;
+	}
+	return -ENODEV;
+}
+
+EXPORT_SYMBOL(unregister_acpi_bus_type);
+
+static struct acpi_bus_type *acpi_get_bus_type(struct bus_type *type)
+{
+	struct acpi_bus_type *tmp, *ret = NULL;
+
+	down_read(&bus_type_sem);
+	list_for_each_entry(tmp, &bus_type_list, list) {
+		if (tmp->bus == type) {
+			ret = tmp;
+			break;
+		}
+	}
+	up_read(&bus_type_sem);
+	return ret;
+}
+
+static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle)
+{
+	struct acpi_bus_type *tmp;
+	int ret = -ENODEV;
+
+	down_read(&bus_type_sem);
+	list_for_each_entry(tmp, &bus_type_list, list) {
+		if (tmp->find_bridge && !tmp->find_bridge(dev, handle)) {
+			ret = 0;
+			break;
+		}
+	}
+	up_read(&bus_type_sem);
+	return ret;
+}
+
+/* Get PCI root bridge's handle from its segment and bus number */
+struct acpi_find_pci_root {
+	unsigned int seg;
+	unsigned int bus;
+	acpi_handle handle;
+};
+
+static acpi_status
+do_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
+{
+	int *busnr = (int *)data;
+	struct acpi_resource_address64 address;
+
+	if (resource->id != ACPI_RSTYPE_ADDRESS16 &&
+	    resource->id != ACPI_RSTYPE_ADDRESS32 &&
+	    resource->id != ACPI_RSTYPE_ADDRESS64)
+		return AE_OK;
+
+	acpi_resource_to_address64(resource, &address);
+	if ((address.address_length > 0) &&
+	    (address.resource_type == ACPI_BUS_NUMBER_RANGE))
+		*busnr = address.min_address_range;
+
+	return AE_OK;
+}
+
+static int get_root_bridge_busnr(acpi_handle handle)
+{
+	acpi_status status;
+	int bus, bbn;
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+
+	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
+
+	status = acpi_evaluate_integer(handle, METHOD_NAME__BBN, NULL,
+				       (unsigned long *)&bbn);
+	if (status == AE_NOT_FOUND) {
+		/* Assume bus = 0 */
+		printk(KERN_INFO PREFIX
+		       "Assume root bridge [%s] bus is 0\n",
+		       (char *)buffer.pointer);
+		status = AE_OK;
+		bbn = 0;
+	}
+	if (ACPI_FAILURE(status)) {
+		bbn = -ENODEV;
+		goto exit;
+	}
+	if (bbn > 0)
+		goto exit;
+
+	/* _BBN in some systems return 0 for all root bridges */
+	bus = -1;
+	status = acpi_walk_resources(handle, METHOD_NAME__CRS,
+				     do_root_bridge_busnr_callback, &bus);
+	/* If _CRS failed, we just use _BBN */
+	if (ACPI_FAILURE(status) || (bus == -1))
+		goto exit;
+	/* We select _CRS */
+	if (bbn != bus) {
+		printk(KERN_INFO PREFIX
+		       "_BBN and _CRS returns different value for %s. Select _CRS\n",
+		       (char *)buffer.pointer);
+		bbn = bus;
+	}
+      exit:
+	acpi_os_free(buffer.pointer);
+	return bbn;
+}
+
+static acpi_status
+find_pci_rootbridge(acpi_handle handle, u32 lvl, void *context, void **rv)
+{
+	struct acpi_find_pci_root *find = (struct acpi_find_pci_root *)context;
+	unsigned long seg, bus;
+	acpi_status status;
+	int tmp;
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+
+	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
+
+	status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL, &seg);
+	if (status == AE_NOT_FOUND) {
+		/* Assume seg = 0 */
+		printk(KERN_INFO PREFIX
+		       "Assume root bridge [%s] segment is 0\n",
+		       (char *)buffer.pointer);
+		status = AE_OK;
+		seg = 0;
+	}
+	if (ACPI_FAILURE(status)) {
+		status = AE_CTRL_DEPTH;
+		goto exit;
+	}
+
+	tmp = get_root_bridge_busnr(handle);
+	if (tmp < 0) {
+		printk(KERN_ERR PREFIX
+		       "Find root bridge failed for %s\n",
+		       (char *)buffer.pointer);
+		status = AE_CTRL_DEPTH;
+		goto exit;
+	}
+	bus = tmp;
+
+	if (seg == find->seg && bus == find->bus)
+		find->handle = handle;
+	status = AE_OK;
+      exit:
+	acpi_os_free(buffer.pointer);
+	return status;
+}
+
+acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
+{
+	struct acpi_find_pci_root find = { seg, bus, NULL };
+
+	acpi_get_devices(PCI_ROOT_HID_STRING, find_pci_rootbridge, &find, NULL);
+	return find.handle;
+}
+
+/* Get device's handler per its address under its parent */
+struct acpi_find_child {
+	acpi_handle handle;
+	acpi_integer address;
+};
+
+static acpi_status
+do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv)
+{
+	acpi_status status;
+	struct acpi_device_info *info;
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+	struct acpi_find_child *find = (struct acpi_find_child *)context;
+
+	status = acpi_get_object_info(handle, &buffer);
+	if (ACPI_SUCCESS(status)) {
+		info = buffer.pointer;
+		if (info->address == find->address)
+			find->handle = handle;
+		acpi_os_free(buffer.pointer);
+	}
+	return AE_OK;
+}
+
+acpi_handle acpi_get_child(acpi_handle parent, acpi_integer address)
+{
+	struct acpi_find_child find = { NULL, address };
+
+	if (!parent)
+		return NULL;
+	acpi_walk_namespace(ACPI_TYPE_DEVICE, parent,
+			    1, do_acpi_find_child, &find, NULL);
+	return find.handle;
+}
+
+EXPORT_SYMBOL(acpi_get_child);
+
+/* Link ACPI devices with physical devices */
+static void acpi_glue_data_handler(acpi_handle handle,
+				   u32 function, void *context)
+{
+	/* we provide an empty handler */
+}
+
+/* Note: a success call will increase reference count by one */
+struct device *acpi_get_physical_device(acpi_handle handle)
+{
+	acpi_status status;
+	struct device *dev;
+
+	status = acpi_get_data(handle, acpi_glue_data_handler, (void **)&dev);
+	if (ACPI_SUCCESS(status))
+		return get_device(dev);
+	return NULL;
+}
+
+EXPORT_SYMBOL(acpi_get_physical_device);
+
+static int acpi_bind_one(struct device *dev, acpi_handle handle)
+{
+	acpi_status status;
+
+	if (dev->firmware_data) {
+		printk(KERN_WARNING PREFIX
+		       "Drivers changed 'firmware_data' for %s\n", dev->bus_id);
+		return -EINVAL;
+	}
+	get_device(dev);
+	status = acpi_attach_data(handle, acpi_glue_data_handler, dev);
+	if (ACPI_FAILURE(status)) {
+		put_device(dev);
+		return -EINVAL;
+	}
+	dev->firmware_data = handle;
+
+	return 0;
+}
+
+static int acpi_unbind_one(struct device *dev)
+{
+	if (!dev->firmware_data)
+		return 0;
+	if (dev == acpi_get_physical_device(dev->firmware_data)) {
+		/* acpi_get_physical_device increase refcnt by one */
+		put_device(dev);
+		acpi_detach_data(dev->firmware_data, acpi_glue_data_handler);
+		dev->firmware_data = NULL;
+		/* acpi_bind_one increase refcnt by one */
+		put_device(dev);
+	} else {
+		printk(KERN_ERR PREFIX
+		       "Oops, 'firmware_data' corrupt for %s\n", dev->bus_id);
+	}
+	return 0;
+}
+
+static int acpi_platform_notify(struct device *dev)
+{
+	struct acpi_bus_type *type;
+	acpi_handle handle;
+	int ret = -EINVAL;
+
+	if (!dev->bus || !dev->parent) {
+		/* bridge devices genernally haven't bus or parent */
+		ret = acpi_find_bridge_device(dev, &handle);
+		goto end;
+	}
+	type = acpi_get_bus_type(dev->bus);
+	if (!type) {
+		printk(KERN_INFO PREFIX "No ACPI bus support for %s\n",
+		       dev->bus_id);
+		ret = -EINVAL;
+		goto end;
+	}
+	if ((ret = type->find_device(dev, &handle)) != 0)
+		printk(KERN_INFO PREFIX "Can't get handler for %s\n",
+		       dev->bus_id);
+      end:
+	if (!ret)
+		acpi_bind_one(dev, handle);
+
+#if ACPI_GLUE_DEBUG
+	if (!ret) {
+		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+
+		acpi_get_name(dev->firmware_data, ACPI_FULL_PATHNAME, &buffer);
+		DBG("Device %s -> %s\n", dev->bus_id, (char *)buffer.pointer);
+		acpi_os_free(buffer.pointer);
+	} else
+		DBG("Device %s -> No ACPI support\n", dev->bus_id);
+#endif
+
+	return ret;
+}
+
+static int acpi_platform_notify_remove(struct device *dev)
+{
+	acpi_unbind_one(dev);
+	return 0;
+}
+
+static int __init init_acpi_device_notify(void)
+{
+	if (acpi_disabled)
+		return 0;
+	if (platform_notify || platform_notify_remove) {
+		printk(KERN_ERR PREFIX "Can't use platform_notify\n");
+		return 0;
+	}
+	platform_notify = acpi_platform_notify;
+	platform_notify_remove = acpi_platform_notify_remove;
+	return 0;
+}
+
+arch_initcall(init_acpi_device_notify);

drivers/acpi/ibm_acpi.c

···
 	return 0;
 }
 
-static int device_add(struct acpi_device *device)
+static int ibmacpi_device_add(struct acpi_device *device)
 {
 	return 0;
 }
···
 	memset(ibm->driver, 0, sizeof(struct acpi_driver));
 	sprintf(ibm->driver->name, "%s/%s", IBM_NAME, ibm->name);
 	ibm->driver->ids = ibm->hid;
-	ibm->driver->ops.add = &device_add;
+	ibm->driver->ops.add = &ibmacpi_device_add;
 
 	ret = acpi_bus_register_driver(ibm->driver);
 	if (ret < 0) {

include/acpi/acpi_bus.h

···
 int acpi_create_dir(struct acpi_device *);
 void acpi_remove_dir(struct acpi_device *);
 
+
+/*
+ * Bind physical devices with ACPI devices
+ */
+#include <linux/device.h>
+struct acpi_bus_type {
+	struct list_head	list;
+	struct bus_type		*bus;
+	/* For general devices under the bus*/
+	int (*find_device)(struct device *, acpi_handle*);
+	/* For bridges, such as PCI root bridge, IDE controller */
+	int (*find_bridge)(struct device *, acpi_handle *);
+};
+int register_acpi_bus_type(struct acpi_bus_type *);
+int unregister_acpi_bus_type(struct acpi_bus_type *);
+struct device *acpi_get_physical_device(acpi_handle);
+/* helper */
+acpi_handle acpi_get_child(acpi_handle, acpi_integer);
+acpi_handle acpi_get_pci_rootbridge_handle(unsigned int, unsigned int);
+#define DEVICE_ACPI_HANDLE(dev) ((acpi_handle)((dev)->firmware_data))
+
 #endif /*CONFIG_ACPI_BUS*/
 
 #endif /*__ACPI_BUS_H__*/

include/linux/device.h

···
 	struct device_driver *driver;	/* which driver has allocated this
 					   device */
 	void		*driver_data;	/* data private to the driver */
-	void		*platform_data;	/* Platform specific data (e.g. ACPI,
-					   BIOS data relevant to device) */
+	void		*platform_data;	/* Platform specific data, device
+					   core doesn't touch it */
+	void		*firmware_data; /* Firmware specific data (e.g. ACPI,
+					   BIOS data),reserved for device core*/
 	struct dev_pm_info	power;
 
 	u64		*dma_mask;	/* dma mask (if dma'able device) */