2 * Link physical devices with ACPI devices support
4 * Copyright (c) 2005 David Shaohua Li <shaohua.li@intel.com>
5 * Copyright (c) 2005 Intel Corp.
7 * This file is released under the GPLv2.
9 #include <linux/export.h>
10 #include <linux/init.h>
11 #include <linux/list.h>
12 #include <linux/device.h>
13 #include <linux/slab.h>
14 #include <linux/rwsem.h>
15 #include <linux/acpi.h>
16 #include <linux/dma-mapping.h>
20 #define ACPI_GLUE_DEBUG 0
22 #define DBG(fmt, ...) \
23 printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__)
25 #define DBG(fmt, ...) \
28 printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__); \
31 static LIST_HEAD(bus_type_list);
32 static DECLARE_RWSEM(bus_type_sem);
34 #define PHYSICAL_NODE_STRING "physical_node"
35 #define PHYSICAL_NODE_NAME_SIZE (sizeof(PHYSICAL_NODE_STRING) + 10)
37 int register_acpi_bus_type(struct acpi_bus_type *type)
41 if (type && type->match && type->find_companion) {
42 down_write(&bus_type_sem);
43 list_add_tail(&type->list, &bus_type_list);
44 up_write(&bus_type_sem);
45 printk(KERN_INFO PREFIX "bus type %s registered\n", type->name);
50 EXPORT_SYMBOL_GPL(register_acpi_bus_type);
52 int unregister_acpi_bus_type(struct acpi_bus_type *type)
57 down_write(&bus_type_sem);
58 list_del_init(&type->list);
59 up_write(&bus_type_sem);
60 printk(KERN_INFO PREFIX "bus type %s unregistered\n",
66 EXPORT_SYMBOL_GPL(unregister_acpi_bus_type);
68 static struct acpi_bus_type *acpi_get_bus_type(struct device *dev)
70 struct acpi_bus_type *tmp, *ret = NULL;
72 down_read(&bus_type_sem);
73 list_for_each_entry(tmp, &bus_type_list, list) {
74 if (tmp->match(dev)) {
79 up_read(&bus_type_sem);
83 #define FIND_CHILD_MIN_SCORE 1
84 #define FIND_CHILD_MAX_SCORE 2
86 static int find_child_checks(struct acpi_device *adev, bool check_children)
88 bool sta_present = true;
89 unsigned long long sta;
92 status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
93 if (status == AE_NOT_FOUND)
95 else if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_ENABLED))
98 if (check_children && list_empty(&adev->children))
101 return sta_present ? FIND_CHILD_MAX_SCORE : FIND_CHILD_MIN_SCORE;
104 struct acpi_device *acpi_find_child_device(struct acpi_device *parent,
105 u64 address, bool check_children)
107 struct acpi_device *adev, *ret = NULL;
113 list_for_each_entry(adev, &parent->children, node) {
114 unsigned long long addr;
118 status = acpi_evaluate_integer(adev->handle, METHOD_NAME__ADR,
120 if (ACPI_FAILURE(status) || addr != address)
124 /* This is the first matching object. Save it. */
129 * There is more than one matching device object with the same
130 * _ADR value. That really is unexpected, so we are kind of
131 * beyond the scope of the spec here. We have to choose which
132 * one to return, though.
134 * First, check if the previously found object is good enough
135 * and return it if so. Second, do the same for the object that
139 ret_score = find_child_checks(ret, check_children);
140 if (ret_score == FIND_CHILD_MAX_SCORE)
143 score = find_child_checks(adev, check_children);
144 if (score == FIND_CHILD_MAX_SCORE) {
146 } else if (score > ret_score) {
153 EXPORT_SYMBOL_GPL(acpi_find_child_device);
155 static void acpi_physnode_link_name(char *buf, unsigned int node_id)
158 snprintf(buf, PHYSICAL_NODE_NAME_SIZE,
159 PHYSICAL_NODE_STRING "%u", node_id);
161 strcpy(buf, PHYSICAL_NODE_STRING);
164 int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
166 struct acpi_device_physical_node *physical_node, *pn;
167 char physical_node_name[PHYSICAL_NODE_NAME_SIZE];
168 struct list_head *physnode_list;
169 unsigned int node_id;
170 int retval = -EINVAL;
171 enum dev_dma_attr attr;
173 if (has_acpi_companion(dev)) {
175 dev_warn(dev, "ACPI companion already set\n");
178 acpi_dev = ACPI_COMPANION(dev);
184 get_device(&acpi_dev->dev);
186 physical_node = kzalloc(sizeof(*physical_node), GFP_KERNEL);
187 if (!physical_node) {
192 mutex_lock(&acpi_dev->physical_node_lock);
195 * Keep the list sorted by node_id so that the IDs of removed nodes can
196 * be recycled easily.
198 physnode_list = &acpi_dev->physical_node_list;
200 list_for_each_entry(pn, &acpi_dev->physical_node_list, node) {
202 if (pn->dev == dev) {
203 mutex_unlock(&acpi_dev->physical_node_lock);
205 dev_warn(dev, "Already associated with ACPI node\n");
206 kfree(physical_node);
207 if (ACPI_COMPANION(dev) != acpi_dev)
211 put_device(&acpi_dev->dev);
214 if (pn->node_id == node_id) {
215 physnode_list = &pn->node;
220 physical_node->node_id = node_id;
221 physical_node->dev = dev;
222 list_add(&physical_node->node, physnode_list);
223 acpi_dev->physical_node_count++;
225 if (!has_acpi_companion(dev))
226 ACPI_COMPANION_SET(dev, acpi_dev);
228 attr = acpi_get_dma_attr(acpi_dev);
229 if (attr != DEV_DMA_NOT_SUPPORTED)
230 acpi_dma_configure(dev, attr);
232 acpi_physnode_link_name(physical_node_name, node_id);
233 retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
236 dev_err(&acpi_dev->dev, "Failed to create link %s (%d)\n",
237 physical_node_name, retval);
239 retval = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
242 dev_err(dev, "Failed to create link firmware_node (%d)\n",
245 mutex_unlock(&acpi_dev->physical_node_lock);
247 if (acpi_dev->wakeup.flags.valid)
248 device_set_wakeup_capable(dev, true);
253 ACPI_COMPANION_SET(dev, NULL);
255 put_device(&acpi_dev->dev);
258 EXPORT_SYMBOL_GPL(acpi_bind_one);
260 int acpi_unbind_one(struct device *dev)
262 struct acpi_device *acpi_dev = ACPI_COMPANION(dev);
263 struct acpi_device_physical_node *entry;
268 mutex_lock(&acpi_dev->physical_node_lock);
270 list_for_each_entry(entry, &acpi_dev->physical_node_list, node)
271 if (entry->dev == dev) {
272 char physnode_name[PHYSICAL_NODE_NAME_SIZE];
274 list_del(&entry->node);
275 acpi_dev->physical_node_count--;
277 acpi_physnode_link_name(physnode_name, entry->node_id);
278 sysfs_remove_link(&acpi_dev->dev.kobj, physnode_name);
279 sysfs_remove_link(&dev->kobj, "firmware_node");
280 ACPI_COMPANION_SET(dev, NULL);
281 /* Drop references taken by acpi_bind_one(). */
283 put_device(&acpi_dev->dev);
288 mutex_unlock(&acpi_dev->physical_node_lock);
291 EXPORT_SYMBOL_GPL(acpi_unbind_one);
293 static int acpi_platform_notify(struct device *dev)
295 struct acpi_bus_type *type = acpi_get_bus_type(dev);
296 struct acpi_device *adev;
299 ret = acpi_bind_one(dev, NULL);
301 struct acpi_device *adev;
303 adev = type->find_companion(dev);
305 DBG("Unable to get handle for %s\n", dev_name(dev));
309 ret = acpi_bind_one(dev, adev);
313 adev = ACPI_COMPANION(dev);
317 if (type && type->setup)
319 else if (adev->handler && adev->handler->bind)
320 adev->handler->bind(dev);
325 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
327 acpi_get_name(ACPI_HANDLE(dev), ACPI_FULL_PATHNAME, &buffer);
328 DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
329 kfree(buffer.pointer);
331 DBG("Device %s -> No ACPI support\n", dev_name(dev));
337 static int acpi_platform_notify_remove(struct device *dev)
339 struct acpi_device *adev = ACPI_COMPANION(dev);
340 struct acpi_bus_type *type;
345 type = acpi_get_bus_type(dev);
346 if (type && type->cleanup)
348 else if (adev->handler && adev->handler->unbind)
349 adev->handler->unbind(dev);
351 acpi_unbind_one(dev);
355 void __init init_acpi_device_notify(void)
357 if (platform_notify || platform_notify_remove) {
358 printk(KERN_ERR PREFIX "Can't use platform_notify\n");
361 platform_notify = acpi_platform_notify;
362 platform_notify_remove = acpi_platform_notify_remove;