/*
* Link physical devices with ACPI devices support
*
* Copyright (c) 2005 David Shaohua Li <shaohua.li@intel.com>
* 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);
