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1/*
2 * Link physical devices with ACPI devices support
3 *
4 * Copyright (c) 2005 David Shaohua Li <shaohua.li@intel.com>
5 * Copyright (c) 2005 Intel Corp.
6 *
7 * This file is released under the GPLv2.
8 */
9#include <linux/init.h>
10#include <linux/list.h>
11#include <linux/device.h>
12#include <linux/slab.h>
13#include <linux/rwsem.h>
14#include <linux/acpi.h>
15
16#include "internal.h"
17
18#define ACPI_GLUE_DEBUG 0
19#if ACPI_GLUE_DEBUG
20#define DBG(x...) printk(PREFIX x)
21#else
22#define DBG(x...) do { } while(0)
23#endif
24static LIST_HEAD(bus_type_list);
25static DECLARE_RWSEM(bus_type_sem);
26
27int register_acpi_bus_type(struct acpi_bus_type *type)
28{
29 if (acpi_disabled)
30 return -ENODEV;
31 if (type && type->bus && type->find_device) {
32 down_write(&bus_type_sem);
33 list_add_tail(&type->list, &bus_type_list);
34 up_write(&bus_type_sem);
35 printk(KERN_INFO PREFIX "bus type %s registered\n",
36 type->bus->name);
37 return 0;
38 }
39 return -ENODEV;
40}
41
42int unregister_acpi_bus_type(struct acpi_bus_type *type)
43{
44 if (acpi_disabled)
45 return 0;
46 if (type) {
47 down_write(&bus_type_sem);
48 list_del_init(&type->list);
49 up_write(&bus_type_sem);
50 printk(KERN_INFO PREFIX "ACPI bus type %s unregistered\n",
51 type->bus->name);
52 return 0;
53 }
54 return -ENODEV;
55}
56
57static struct acpi_bus_type *acpi_get_bus_type(struct bus_type *type)
58{
59 struct acpi_bus_type *tmp, *ret = NULL;
60
61 down_read(&bus_type_sem);
62 list_for_each_entry(tmp, &bus_type_list, list) {
63 if (tmp->bus == type) {
64 ret = tmp;
65 break;
66 }
67 }
68 up_read(&bus_type_sem);
69 return ret;
70}
71
72static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle)
73{
74 struct acpi_bus_type *tmp;
75 int ret = -ENODEV;
76
77 down_read(&bus_type_sem);
78 list_for_each_entry(tmp, &bus_type_list, list) {
79 if (tmp->find_bridge && !tmp->find_bridge(dev, handle)) {
80 ret = 0;
81 break;
82 }
83 }
84 up_read(&bus_type_sem);
85 return ret;
86}
87
88/* Get device's handler per its address under its parent */
89struct acpi_find_child {
90 acpi_handle handle;
91 u64 address;
92};
93
94static acpi_status
95do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv)
96{
97 acpi_status status;
98 struct acpi_device_info *info;
99 struct acpi_find_child *find = context;
100
101 status = acpi_get_object_info(handle, &info);
102 if (ACPI_SUCCESS(status)) {
103 if ((info->address == find->address)
104 && (info->valid & ACPI_VALID_ADR))
105 find->handle = handle;
106 kfree(info);
107 }
108 return AE_OK;
109}
110
111acpi_handle acpi_get_child(acpi_handle parent, u64 address)
112{
113 struct acpi_find_child find = { NULL, address };
114
115 if (!parent)
116 return NULL;
117 acpi_walk_namespace(ACPI_TYPE_DEVICE, parent,
118 1, do_acpi_find_child, NULL, &find, NULL);
119 return find.handle;
120}
121
122EXPORT_SYMBOL(acpi_get_child);
123
124/* Link ACPI devices with physical devices */
125static void acpi_glue_data_handler(acpi_handle handle,
126 void *context)
127{
128 /* we provide an empty handler */
129}
130
131/* Note: a success call will increase reference count by one */
132struct device *acpi_get_physical_device(acpi_handle handle)
133{
134 acpi_status status;
135 struct device *dev;
136
137 status = acpi_get_data(handle, acpi_glue_data_handler, (void **)&dev);
138 if (ACPI_SUCCESS(status))
139 return get_device(dev);
140 return NULL;
141}
142
143EXPORT_SYMBOL(acpi_get_physical_device);
144
145static int acpi_bind_one(struct device *dev, acpi_handle handle)
146{
147 struct acpi_device *acpi_dev;
148 acpi_status status;
149
150 if (dev->archdata.acpi_handle) {
151 dev_warn(dev, "Drivers changed 'acpi_handle'\n");
152 return -EINVAL;
153 }
154 get_device(dev);
155 status = acpi_attach_data(handle, acpi_glue_data_handler, dev);
156 if (ACPI_FAILURE(status)) {
157 put_device(dev);
158 return -EINVAL;
159 }
160 dev->archdata.acpi_handle = handle;
161
162 status = acpi_bus_get_device(handle, &acpi_dev);
163 if (!ACPI_FAILURE(status)) {
164 int ret;
165
166 ret = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
167 "firmware_node");
168 ret = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
169 "physical_node");
170 if (acpi_dev->wakeup.flags.valid)
171 device_set_wakeup_capable(dev, true);
172 }
173
174 return 0;
175}
176
177static int acpi_unbind_one(struct device *dev)
178{
179 if (!dev->archdata.acpi_handle)
180 return 0;
181 if (dev == acpi_get_physical_device(dev->archdata.acpi_handle)) {
182 struct acpi_device *acpi_dev;
183
184 /* acpi_get_physical_device increase refcnt by one */
185 put_device(dev);
186
187 if (!acpi_bus_get_device(dev->archdata.acpi_handle,
188 &acpi_dev)) {
189 sysfs_remove_link(&dev->kobj, "firmware_node");
190 sysfs_remove_link(&acpi_dev->dev.kobj, "physical_node");
191 }
192
193 acpi_detach_data(dev->archdata.acpi_handle,
194 acpi_glue_data_handler);
195 dev->archdata.acpi_handle = NULL;
196 /* acpi_bind_one increase refcnt by one */
197 put_device(dev);
198 } else {
199 dev_err(dev, "Oops, 'acpi_handle' corrupt\n");
200 }
201 return 0;
202}
203
204static int acpi_platform_notify(struct device *dev)
205{
206 struct acpi_bus_type *type;
207 acpi_handle handle;
208 int ret = -EINVAL;
209
210 if (!dev->bus || !dev->parent) {
211 /* bridge devices genernally haven't bus or parent */
212 ret = acpi_find_bridge_device(dev, &handle);
213 goto end;
214 }
215 type = acpi_get_bus_type(dev->bus);
216 if (!type) {
217 DBG("No ACPI bus support for %s\n", dev_name(dev));
218 ret = -EINVAL;
219 goto end;
220 }
221 if ((ret = type->find_device(dev, &handle)) != 0)
222 DBG("Can't get handler for %s\n", dev_name(dev));
223 end:
224 if (!ret)
225 acpi_bind_one(dev, handle);
226
227#if ACPI_GLUE_DEBUG
228 if (!ret) {
229 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
230
231 acpi_get_name(dev->archdata.acpi_handle,
232 ACPI_FULL_PATHNAME, &buffer);
233 DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
234 kfree(buffer.pointer);
235 } else
236 DBG("Device %s -> No ACPI support\n", dev_name(dev));
237#endif
238
239 return ret;
240}
241
242static int acpi_platform_notify_remove(struct device *dev)
243{
244 acpi_unbind_one(dev);
245 return 0;
246}
247
248int __init init_acpi_device_notify(void)
249{
250 if (platform_notify || platform_notify_remove) {
251 printk(KERN_ERR PREFIX "Can't use platform_notify\n");
252 return 0;
253 }
254 platform_notify = acpi_platform_notify;
255 platform_notify_remove = acpi_platform_notify_remove;
256 return 0;
257}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Link physical devices with ACPI devices support
4 *
5 * Copyright (c) 2005 David Shaohua Li <shaohua.li@intel.com>
6 * Copyright (c) 2005 Intel Corp.
7 */
8
9#define pr_fmt(fmt) "ACPI: " fmt
10
11#include <linux/acpi_iort.h>
12#include <linux/export.h>
13#include <linux/init.h>
14#include <linux/list.h>
15#include <linux/device.h>
16#include <linux/slab.h>
17#include <linux/rwsem.h>
18#include <linux/acpi.h>
19#include <linux/dma-mapping.h>
20#include <linux/platform_device.h>
21
22#include "internal.h"
23
24static LIST_HEAD(bus_type_list);
25static DECLARE_RWSEM(bus_type_sem);
26
27#define PHYSICAL_NODE_STRING "physical_node"
28#define PHYSICAL_NODE_NAME_SIZE (sizeof(PHYSICAL_NODE_STRING) + 10)
29
30int register_acpi_bus_type(struct acpi_bus_type *type)
31{
32 if (acpi_disabled)
33 return -ENODEV;
34 if (type && type->match && type->find_companion) {
35 down_write(&bus_type_sem);
36 list_add_tail(&type->list, &bus_type_list);
37 up_write(&bus_type_sem);
38 pr_info("bus type %s registered\n", type->name);
39 return 0;
40 }
41 return -ENODEV;
42}
43EXPORT_SYMBOL_GPL(register_acpi_bus_type);
44
45int unregister_acpi_bus_type(struct acpi_bus_type *type)
46{
47 if (acpi_disabled)
48 return 0;
49 if (type) {
50 down_write(&bus_type_sem);
51 list_del_init(&type->list);
52 up_write(&bus_type_sem);
53 pr_info("bus type %s unregistered\n", type->name);
54 return 0;
55 }
56 return -ENODEV;
57}
58EXPORT_SYMBOL_GPL(unregister_acpi_bus_type);
59
60static struct acpi_bus_type *acpi_get_bus_type(struct device *dev)
61{
62 struct acpi_bus_type *tmp, *ret = NULL;
63
64 down_read(&bus_type_sem);
65 list_for_each_entry(tmp, &bus_type_list, list) {
66 if (tmp->match(dev)) {
67 ret = tmp;
68 break;
69 }
70 }
71 up_read(&bus_type_sem);
72 return ret;
73}
74
75#define FIND_CHILD_MIN_SCORE 1
76#define FIND_CHILD_MAX_SCORE 2
77
78static int find_child_checks(struct acpi_device *adev, bool check_children)
79{
80 bool sta_present = true;
81 unsigned long long sta;
82 acpi_status status;
83
84 status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
85 if (status == AE_NOT_FOUND)
86 sta_present = false;
87 else if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_ENABLED))
88 return -ENODEV;
89
90 if (check_children && list_empty(&adev->children))
91 return -ENODEV;
92
93 /*
94 * If the device has a _HID returning a valid ACPI/PNP device ID, it is
95 * better to make it look less attractive here, so that the other device
96 * with the same _ADR value (that may not have a valid device ID) can be
97 * matched going forward. [This means a second spec violation in a row,
98 * so whatever we do here is best effort anyway.]
99 */
100 return sta_present && !adev->pnp.type.platform_id ?
101 FIND_CHILD_MAX_SCORE : FIND_CHILD_MIN_SCORE;
102}
103
104struct acpi_device *acpi_find_child_device(struct acpi_device *parent,
105 u64 address, bool check_children)
106{
107 struct acpi_device *adev, *ret = NULL;
108 int ret_score = 0;
109
110 if (!parent)
111 return NULL;
112
113 list_for_each_entry(adev, &parent->children, node) {
114 unsigned long long addr;
115 acpi_status status;
116 int score;
117
118 status = acpi_evaluate_integer(adev->handle, METHOD_NAME__ADR,
119 NULL, &addr);
120 if (ACPI_FAILURE(status) || addr != address)
121 continue;
122
123 if (!ret) {
124 /* This is the first matching object. Save it. */
125 ret = adev;
126 continue;
127 }
128 /*
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.
133 *
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
136 * we've just found.
137 */
138 if (!ret_score) {
139 ret_score = find_child_checks(ret, check_children);
140 if (ret_score == FIND_CHILD_MAX_SCORE)
141 return ret;
142 }
143 score = find_child_checks(adev, check_children);
144 if (score == FIND_CHILD_MAX_SCORE) {
145 return adev;
146 } else if (score > ret_score) {
147 ret = adev;
148 ret_score = score;
149 }
150 }
151 return ret;
152}
153EXPORT_SYMBOL_GPL(acpi_find_child_device);
154
155static void acpi_physnode_link_name(char *buf, unsigned int node_id)
156{
157 if (node_id > 0)
158 snprintf(buf, PHYSICAL_NODE_NAME_SIZE,
159 PHYSICAL_NODE_STRING "%u", node_id);
160 else
161 strcpy(buf, PHYSICAL_NODE_STRING);
162}
163
164int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
165{
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
172 if (has_acpi_companion(dev)) {
173 if (acpi_dev) {
174 dev_warn(dev, "ACPI companion already set\n");
175 return -EINVAL;
176 } else {
177 acpi_dev = ACPI_COMPANION(dev);
178 }
179 }
180 if (!acpi_dev)
181 return -EINVAL;
182
183 acpi_dev_get(acpi_dev);
184 get_device(dev);
185 physical_node = kzalloc(sizeof(*physical_node), GFP_KERNEL);
186 if (!physical_node) {
187 retval = -ENOMEM;
188 goto err;
189 }
190
191 mutex_lock(&acpi_dev->physical_node_lock);
192
193 /*
194 * Keep the list sorted by node_id so that the IDs of removed nodes can
195 * be recycled easily.
196 */
197 physnode_list = &acpi_dev->physical_node_list;
198 node_id = 0;
199 list_for_each_entry(pn, &acpi_dev->physical_node_list, node) {
200 /* Sanity check. */
201 if (pn->dev == dev) {
202 mutex_unlock(&acpi_dev->physical_node_lock);
203
204 dev_warn(dev, "Already associated with ACPI node\n");
205 kfree(physical_node);
206 if (ACPI_COMPANION(dev) != acpi_dev)
207 goto err;
208
209 put_device(dev);
210 acpi_dev_put(acpi_dev);
211 return 0;
212 }
213 if (pn->node_id == node_id) {
214 physnode_list = &pn->node;
215 node_id++;
216 }
217 }
218
219 physical_node->node_id = node_id;
220 physical_node->dev = dev;
221 list_add(&physical_node->node, physnode_list);
222 acpi_dev->physical_node_count++;
223
224 if (!has_acpi_companion(dev))
225 ACPI_COMPANION_SET(dev, acpi_dev);
226
227 acpi_physnode_link_name(physical_node_name, node_id);
228 retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
229 physical_node_name);
230 if (retval)
231 dev_err(&acpi_dev->dev, "Failed to create link %s (%d)\n",
232 physical_node_name, retval);
233
234 retval = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
235 "firmware_node");
236 if (retval)
237 dev_err(dev, "Failed to create link firmware_node (%d)\n",
238 retval);
239
240 mutex_unlock(&acpi_dev->physical_node_lock);
241
242 if (acpi_dev->wakeup.flags.valid)
243 device_set_wakeup_capable(dev, true);
244
245 return 0;
246
247 err:
248 ACPI_COMPANION_SET(dev, NULL);
249 put_device(dev);
250 acpi_dev_put(acpi_dev);
251 return retval;
252}
253EXPORT_SYMBOL_GPL(acpi_bind_one);
254
255int acpi_unbind_one(struct device *dev)
256{
257 struct acpi_device *acpi_dev = ACPI_COMPANION(dev);
258 struct acpi_device_physical_node *entry;
259
260 if (!acpi_dev)
261 return 0;
262
263 mutex_lock(&acpi_dev->physical_node_lock);
264
265 list_for_each_entry(entry, &acpi_dev->physical_node_list, node)
266 if (entry->dev == dev) {
267 char physnode_name[PHYSICAL_NODE_NAME_SIZE];
268
269 list_del(&entry->node);
270 acpi_dev->physical_node_count--;
271
272 acpi_physnode_link_name(physnode_name, entry->node_id);
273 sysfs_remove_link(&acpi_dev->dev.kobj, physnode_name);
274 sysfs_remove_link(&dev->kobj, "firmware_node");
275 ACPI_COMPANION_SET(dev, NULL);
276 /* Drop references taken by acpi_bind_one(). */
277 put_device(dev);
278 acpi_dev_put(acpi_dev);
279 kfree(entry);
280 break;
281 }
282
283 mutex_unlock(&acpi_dev->physical_node_lock);
284 return 0;
285}
286EXPORT_SYMBOL_GPL(acpi_unbind_one);
287
288static int acpi_device_notify(struct device *dev)
289{
290 struct acpi_bus_type *type = acpi_get_bus_type(dev);
291 struct acpi_device *adev;
292 int ret;
293
294 ret = acpi_bind_one(dev, NULL);
295 if (ret && type) {
296 struct acpi_device *adev;
297
298 adev = type->find_companion(dev);
299 if (!adev) {
300 pr_debug("Unable to get handle for %s\n", dev_name(dev));
301 ret = -ENODEV;
302 goto out;
303 }
304 ret = acpi_bind_one(dev, adev);
305 if (ret)
306 goto out;
307 }
308 adev = ACPI_COMPANION(dev);
309 if (!adev)
310 goto out;
311
312 if (dev_is_platform(dev))
313 acpi_configure_pmsi_domain(dev);
314
315 if (type && type->setup)
316 type->setup(dev);
317 else if (adev->handler && adev->handler->bind)
318 adev->handler->bind(dev);
319
320 out:
321 if (!ret) {
322 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
323
324 acpi_get_name(ACPI_HANDLE(dev), ACPI_FULL_PATHNAME, &buffer);
325 pr_debug("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
326 kfree(buffer.pointer);
327 } else {
328 pr_debug("Device %s -> No ACPI support\n", dev_name(dev));
329 }
330
331 return ret;
332}
333
334static int acpi_device_notify_remove(struct device *dev)
335{
336 struct acpi_device *adev = ACPI_COMPANION(dev);
337 struct acpi_bus_type *type;
338
339 if (!adev)
340 return 0;
341
342 type = acpi_get_bus_type(dev);
343 if (type && type->cleanup)
344 type->cleanup(dev);
345 else if (adev->handler && adev->handler->unbind)
346 adev->handler->unbind(dev);
347
348 acpi_unbind_one(dev);
349 return 0;
350}
351
352int acpi_platform_notify(struct device *dev, enum kobject_action action)
353{
354 switch (action) {
355 case KOBJ_ADD:
356 acpi_device_notify(dev);
357 break;
358 case KOBJ_REMOVE:
359 acpi_device_notify_remove(dev);
360 break;
361 default:
362 break;
363 }
364 return 0;
365}