/*
* 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/export.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/rwsem.h>
#include <linux/acpi.h>
#include "internal.h"
#define ACPI_GLUE_DEBUG 0
#if ACPI_GLUE_DEBUG
#define DBG(fmt, ...) \
printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__)
#else
#define DBG(fmt, ...) \
do { \
if (0) \
printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__); \
} while (0)
#endif
static LIST_HEAD(bus_type_list);
static DECLARE_RWSEM(bus_type_sem);
#define PHYSICAL_NODE_STRING "physical_node"
#define PHYSICAL_NODE_NAME_SIZE (sizeof(PHYSICAL_NODE_STRING) + 10)
int register_acpi_bus_type(struct acpi_bus_type *type)
{
if (acpi_disabled)
return -ENODEV;
if (type && type->match && type->find_companion) {
down_write(&bus_type_sem);
list_add_tail(&type->list, &bus_type_list);
up_write(&bus_type_sem);
printk(KERN_INFO PREFIX "bus type %s registered\n", type->name);
return 0;
}
return -ENODEV;
}
EXPORT_SYMBOL_GPL(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);
printk(KERN_INFO PREFIX "bus type %s unregistered\n",
type->name);
return 0;
}
return -ENODEV;
}
EXPORT_SYMBOL_GPL(unregister_acpi_bus_type);
static struct acpi_bus_type *acpi_get_bus_type(struct device *dev)
{
struct acpi_bus_type *tmp, *ret = NULL;
down_read(&bus_type_sem);
list_for_each_entry(tmp, &bus_type_list, list) {
if (tmp->match(dev)) {
ret = tmp;
break;
}
}
up_read(&bus_type_sem);
return ret;
}
#define FIND_CHILD_MIN_SCORE 1
#define FIND_CHILD_MAX_SCORE 2
static int find_child_checks(struct acpi_device *adev, bool check_children)
{
bool sta_present = true;
unsigned long long sta;
acpi_status status;
status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
if (status == AE_NOT_FOUND)
sta_present = false;
else if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_ENABLED))
return -ENODEV;
if (check_children && list_empty(&adev->children))
return -ENODEV;
return sta_present ? FIND_CHILD_MAX_SCORE : FIND_CHILD_MIN_SCORE;
}
struct acpi_device *acpi_find_child_device(struct acpi_device *parent,
u64 address, bool check_children)
{
struct acpi_device *adev, *ret = NULL;
int ret_score = 0;
if (!parent)
return NULL;
list_for_each_entry(adev, &parent->children, node) {
unsigned long long addr;
acpi_status status;
int score;
status = acpi_evaluate_integer(adev->handle, METHOD_NAME__ADR,
NULL, &addr);
if (ACPI_FAILURE(status) || addr != address)
continue;
if (!ret) {
/* This is the first matching object. Save it. */
ret = adev;
continue;
}
/*
* There is more than one matching device object with the same
* _ADR value. That really is unexpected, so we are kind of
* beyond the scope of the spec here. We have to choose which
* one to return, though.
*
* First, check if the previously found object is good enough
* and return it if so. Second, do the same for the object that
* we've just found.
*/
if (!ret_score) {
ret_score = find_child_checks(ret, check_children);
if (ret_score == FIND_CHILD_MAX_SCORE)
return ret;
}
score = find_child_checks(adev, check_children);
if (score == FIND_CHILD_MAX_SCORE) {
return adev;
} else if (score > ret_score) {
ret = adev;
ret_score = score;
}
}
return ret;
}
EXPORT_SYMBOL_GPL(acpi_find_child_device);
static void acpi_physnode_link_name(char *buf, unsigned int node_id)
{
if (node_id > 0)
snprintf(buf, PHYSICAL_NODE_NAME_SIZE,
PHYSICAL_NODE_STRING "%u", node_id);
else
strcpy(buf, PHYSICAL_NODE_STRING);
}
int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
{
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_COMPANION(dev)) {
if (acpi_dev) {
dev_warn(dev, "ACPI companion already set\n");
return -EINVAL;
} else {
acpi_dev = ACPI_COMPANION(dev);
}
}
if (!acpi_dev)
return -EINVAL;
get_device(&acpi_dev->dev);
get_device(dev);
physical_node = kzalloc(sizeof(*physical_node), GFP_KERNEL);
if (!physical_node) {
retval = -ENOMEM;
goto err;
}
mutex_lock(&acpi_dev->physical_node_lock);
/*
* Keep the list sorted by node_id so that the IDs of removed nodes can
* be recycled easily.
*/
physnode_list = &acpi_dev->physical_node_list;
node_id = 0;
list_for_each_entry(pn, &acpi_dev->physical_node_list, node) {
/* Sanity check. */
if (pn->dev == dev) {
mutex_unlock(&acpi_dev->physical_node_lock);
dev_warn(dev, "Already associated with ACPI node\n");
kfree(physical_node);
if (ACPI_COMPANION(dev) != acpi_dev)
goto err;
put_device(dev);
put_device(&acpi_dev->dev);
return 0;
}
if (pn->node_id == node_id) {
physnode_list = &pn->node;
node_id++;
}
}
physical_node->node_id = node_id;
physical_node->dev = dev;
list_add(&physical_node->node, physnode_list);
acpi_dev->physical_node_count++;
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,
physical_node_name);
if (retval)
dev_err(&acpi_dev->dev, "Failed to create link %s (%d)\n",
physical_node_name, retval);
retval = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
"firmware_node");
if (retval)
dev_err(dev, "Failed to create link firmware_node (%d)\n",
retval);
mutex_unlock(&acpi_dev->physical_node_lock);
if (acpi_dev->wakeup.flags.valid)
device_set_wakeup_capable(dev, true);
return 0;
err:
ACPI_COMPANION_SET(dev, NULL);
put_device(dev);
put_device(&acpi_dev->dev);
return retval;
}
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;
if (!acpi_dev)
return 0;
mutex_lock(&acpi_dev->physical_node_lock);
list_for_each_entry(entry, &acpi_dev->physical_node_list, node)
if (entry->dev == dev) {
char physnode_name[PHYSICAL_NODE_NAME_SIZE];
list_del(&entry->node);
acpi_dev->physical_node_count--;
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_COMPANION_SET(dev, NULL);
/* Drop references taken by acpi_bind_one(). */
put_device(dev);
put_device(&acpi_dev->dev);
kfree(entry);
break;
}
mutex_unlock(&acpi_dev->physical_node_lock);
return 0;
}
EXPORT_SYMBOL_GPL(acpi_unbind_one);
static int acpi_platform_notify(struct device *dev)
{
struct acpi_bus_type *type = acpi_get_bus_type(dev);
int ret;
ret = acpi_bind_one(dev, NULL);
if (ret && type) {
struct acpi_device *adev;
adev = type->find_companion(dev);
if (!adev) {
DBG("Unable to get handle for %s\n", dev_name(dev));
ret = -ENODEV;
goto out;
}
ret = acpi_bind_one(dev, adev);
if (ret)
goto out;
}
if (type && type->setup)
type->setup(dev);
out:
#if ACPI_GLUE_DEBUG
if (!ret) {
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
acpi_get_name(ACPI_HANDLE(dev), ACPI_FULL_PATHNAME, &buffer);
DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
kfree(buffer.pointer);
} else
DBG("Device %s -> No ACPI support\n", dev_name(dev));
#endif
return ret;
}
static int acpi_platform_notify_remove(struct device *dev)
{
struct acpi_bus_type *type;
type = acpi_get_bus_type(dev);
if (type && type->cleanup)
type->cleanup(dev);
acpi_unbind_one(dev);
return 0;
}
int __init init_acpi_device_notify(void)
{
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;
}
