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v3.5.6
  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/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
 17#include "internal.h"
 18
 19#define ACPI_GLUE_DEBUG	0
 20#if ACPI_GLUE_DEBUG
 21#define DBG(x...) printk(PREFIX x)
 
 22#else
 23#define DBG(x...) do { } while(0)
 
 
 
 
 24#endif
 25static LIST_HEAD(bus_type_list);
 26static DECLARE_RWSEM(bus_type_sem);
 27
 
 
 
 28int register_acpi_bus_type(struct acpi_bus_type *type)
 29{
 30	if (acpi_disabled)
 31		return -ENODEV;
 32	if (type && type->bus && type->find_device) {
 33		down_write(&bus_type_sem);
 34		list_add_tail(&type->list, &bus_type_list);
 35		up_write(&bus_type_sem);
 36		printk(KERN_INFO PREFIX "bus type %s registered\n",
 37		       type->bus->name);
 38		return 0;
 39	}
 40	return -ENODEV;
 41}
 
 42
 43int unregister_acpi_bus_type(struct acpi_bus_type *type)
 44{
 45	if (acpi_disabled)
 46		return 0;
 47	if (type) {
 48		down_write(&bus_type_sem);
 49		list_del_init(&type->list);
 50		up_write(&bus_type_sem);
 51		printk(KERN_INFO PREFIX "ACPI bus type %s unregistered\n",
 52		       type->bus->name);
 53		return 0;
 54	}
 55	return -ENODEV;
 56}
 
 57
 58static struct acpi_bus_type *acpi_get_bus_type(struct bus_type *type)
 59{
 60	struct acpi_bus_type *tmp, *ret = NULL;
 61
 62	down_read(&bus_type_sem);
 63	list_for_each_entry(tmp, &bus_type_list, list) {
 64		if (tmp->bus == type) {
 65			ret = tmp;
 66			break;
 67		}
 68	}
 69	up_read(&bus_type_sem);
 70	return ret;
 71}
 72EXPORT_SYMBOL_GPL(register_acpi_bus_type);
 73
 74static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle)
 75{
 76	struct acpi_bus_type *tmp;
 77	int ret = -ENODEV;
 78
 79	down_read(&bus_type_sem);
 80	list_for_each_entry(tmp, &bus_type_list, list) {
 81		if (tmp->find_bridge && !tmp->find_bridge(dev, handle)) {
 82			ret = 0;
 83			break;
 84		}
 85	}
 86	up_read(&bus_type_sem);
 87	return ret;
 88}
 89EXPORT_SYMBOL_GPL(unregister_acpi_bus_type);
 90
 91/* Get device's handler per its address under its parent */
 92struct acpi_find_child {
 93	acpi_handle handle;
 94	u64 address;
 95};
 96
 97static acpi_status
 98do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv)
 99{
 
 
100	acpi_status status;
101	struct acpi_device_info *info;
102	struct acpi_find_child *find = context;
103
104	status = acpi_get_object_info(handle, &info);
105	if (ACPI_SUCCESS(status)) {
106		if ((info->address == find->address)
107			&& (info->valid & ACPI_VALID_ADR))
108			find->handle = handle;
109		kfree(info);
110	}
111	return AE_OK;
112}
113
114acpi_handle acpi_get_child(acpi_handle parent, u64 address)
115{
116	struct acpi_find_child find = { NULL, address };
117
118	if (!parent)
119		return NULL;
120	acpi_walk_namespace(ACPI_TYPE_DEVICE, parent,
121			    1, do_acpi_find_child, NULL, &find, NULL);
122	return find.handle;
 
 
 
 
123}
124
125EXPORT_SYMBOL(acpi_get_child);
126
127/* Link ACPI devices with physical devices */
128static void acpi_glue_data_handler(acpi_handle handle,
129				   void *context)
130{
131	/* we provide an empty handler */
132}
133
134/* Note: a success call will increase reference count by one */
135struct device *acpi_get_physical_device(acpi_handle handle)
136{
137	acpi_status status;
138	struct device *dev;
139
140	status = acpi_get_data(handle, acpi_glue_data_handler, (void **)&dev);
141	if (ACPI_SUCCESS(status))
142		return get_device(dev);
143	return NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
144}
 
145
146EXPORT_SYMBOL(acpi_get_physical_device);
147
148static int acpi_bind_one(struct device *dev, acpi_handle handle)
149{
150	struct acpi_device *acpi_dev;
151	acpi_status status;
152
153	if (dev->archdata.acpi_handle) {
154		dev_warn(dev, "Drivers changed 'acpi_handle'\n");
155		return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
156	}
157	get_device(dev);
158	status = acpi_attach_data(handle, acpi_glue_data_handler, dev);
159	if (ACPI_FAILURE(status)) {
160		put_device(dev);
161		return -EINVAL;
162	}
163	dev->archdata.acpi_handle = handle;
164
165	status = acpi_bus_get_device(handle, &acpi_dev);
166	if (!ACPI_FAILURE(status)) {
167		int ret;
168
169		ret = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
170				"firmware_node");
171		ret = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
172				"physical_node");
173		if (acpi_dev->wakeup.flags.valid)
174			device_set_wakeup_capable(dev, true);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
175	}
176
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
177	return 0;
 
 
 
 
 
 
178}
 
179
180static int acpi_unbind_one(struct device *dev)
181{
182	if (!dev->archdata.acpi_handle)
 
 
 
183		return 0;
184	if (dev == acpi_get_physical_device(dev->archdata.acpi_handle)) {
185		struct acpi_device *acpi_dev;
186
187		/* acpi_get_physical_device increase refcnt by one */
188		put_device(dev);
 
 
 
 
 
 
189
190		if (!acpi_bus_get_device(dev->archdata.acpi_handle,
191					&acpi_dev)) {
192			sysfs_remove_link(&dev->kobj, "firmware_node");
193			sysfs_remove_link(&acpi_dev->dev.kobj, "physical_node");
 
 
 
 
 
194		}
195
196		acpi_detach_data(dev->archdata.acpi_handle,
197				 acpi_glue_data_handler);
198		dev->archdata.acpi_handle = NULL;
199		/* acpi_bind_one increase refcnt by one */
200		put_device(dev);
201	} else {
202		dev_err(dev, "Oops, 'acpi_handle' corrupt\n");
203	}
204	return 0;
205}
 
206
207static int acpi_platform_notify(struct device *dev)
208{
209	struct acpi_bus_type *type;
210	acpi_handle handle;
211	int ret = -EINVAL;
212
213	if (!dev->bus || !dev->parent) {
214		/* bridge devices genernally haven't bus or parent */
215		ret = acpi_find_bridge_device(dev, &handle);
216		goto end;
217	}
218	type = acpi_get_bus_type(dev->bus);
219	if (!type) {
220		DBG("No ACPI bus support for %s\n", dev_name(dev));
221		ret = -EINVAL;
222		goto end;
223	}
224	if ((ret = type->find_device(dev, &handle)) != 0)
225		DBG("Can't get handler for %s\n", dev_name(dev));
226      end:
227	if (!ret)
228		acpi_bind_one(dev, handle);
 
 
 
 
 
 
 
 
 
229
 
230#if ACPI_GLUE_DEBUG
231	if (!ret) {
232		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
233
234		acpi_get_name(dev->archdata.acpi_handle,
235			      ACPI_FULL_PATHNAME, &buffer);
236		DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
237		kfree(buffer.pointer);
238	} else
239		DBG("Device %s -> No ACPI support\n", dev_name(dev));
240#endif
241
242	return ret;
243}
244
245static int acpi_platform_notify_remove(struct device *dev)
246{
 
 
 
 
 
 
 
 
 
 
 
 
247	acpi_unbind_one(dev);
248	return 0;
249}
250
251int __init init_acpi_device_notify(void)
252{
253	if (platform_notify || platform_notify_remove) {
254		printk(KERN_ERR PREFIX "Can't use platform_notify\n");
255		return 0;
256	}
257	platform_notify = acpi_platform_notify;
258	platform_notify_remove = acpi_platform_notify_remove;
259	return 0;
260}
v4.17
  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
 10#include <linux/acpi_iort.h>
 11#include <linux/export.h>
 12#include <linux/init.h>
 13#include <linux/list.h>
 14#include <linux/device.h>
 15#include <linux/slab.h>
 16#include <linux/rwsem.h>
 17#include <linux/acpi.h>
 18#include <linux/dma-mapping.h>
 19#include <linux/platform_device.h>
 20
 21#include "internal.h"
 22
 23#define ACPI_GLUE_DEBUG	0
 24#if ACPI_GLUE_DEBUG
 25#define DBG(fmt, ...)						\
 26	printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__)
 27#else
 28#define DBG(fmt, ...)						\
 29do {								\
 30	if (0)							\
 31		printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__);	\
 32} while (0)
 33#endif
 34static LIST_HEAD(bus_type_list);
 35static DECLARE_RWSEM(bus_type_sem);
 36
 37#define PHYSICAL_NODE_STRING "physical_node"
 38#define PHYSICAL_NODE_NAME_SIZE (sizeof(PHYSICAL_NODE_STRING) + 10)
 39
 40int register_acpi_bus_type(struct acpi_bus_type *type)
 41{
 42	if (acpi_disabled)
 43		return -ENODEV;
 44	if (type && type->match && type->find_companion) {
 45		down_write(&bus_type_sem);
 46		list_add_tail(&type->list, &bus_type_list);
 47		up_write(&bus_type_sem);
 48		printk(KERN_INFO PREFIX "bus type %s registered\n", type->name);
 
 49		return 0;
 50	}
 51	return -ENODEV;
 52}
 53EXPORT_SYMBOL_GPL(register_acpi_bus_type);
 54
 55int unregister_acpi_bus_type(struct acpi_bus_type *type)
 56{
 57	if (acpi_disabled)
 58		return 0;
 59	if (type) {
 60		down_write(&bus_type_sem);
 61		list_del_init(&type->list);
 62		up_write(&bus_type_sem);
 63		printk(KERN_INFO PREFIX "bus type %s unregistered\n",
 64		       type->name);
 65		return 0;
 66	}
 67	return -ENODEV;
 68}
 69EXPORT_SYMBOL_GPL(unregister_acpi_bus_type);
 70
 71static struct acpi_bus_type *acpi_get_bus_type(struct device *dev)
 72{
 73	struct acpi_bus_type *tmp, *ret = NULL;
 74
 75	down_read(&bus_type_sem);
 76	list_for_each_entry(tmp, &bus_type_list, list) {
 77		if (tmp->match(dev)) {
 78			ret = tmp;
 79			break;
 80		}
 81	}
 82	up_read(&bus_type_sem);
 83	return ret;
 84}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 85
 86#define FIND_CHILD_MIN_SCORE	1
 87#define FIND_CHILD_MAX_SCORE	2
 
 
 
 88
 89static int find_child_checks(struct acpi_device *adev, bool check_children)
 
 90{
 91	bool sta_present = true;
 92	unsigned long long sta;
 93	acpi_status status;
 
 
 94
 95	status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
 96	if (status == AE_NOT_FOUND)
 97		sta_present = false;
 98	else if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_ENABLED))
 99		return -ENODEV;
 
 
 
 
100
101	if (check_children && list_empty(&adev->children))
102		return -ENODEV;
 
103
104	/*
105	 * If the device has a _HID returning a valid ACPI/PNP device ID, it is
106	 * better to make it look less attractive here, so that the other device
107	 * with the same _ADR value (that may not have a valid device ID) can be
108	 * matched going forward.  [This means a second spec violation in a row,
109	 * so whatever we do here is best effort anyway.]
110	 */
111	return sta_present && !adev->pnp.type.platform_id ?
112			FIND_CHILD_MAX_SCORE : FIND_CHILD_MIN_SCORE;
113}
114
115struct acpi_device *acpi_find_child_device(struct acpi_device *parent,
116					   u64 address, bool check_children)
 
 
 
117{
118	struct acpi_device *adev, *ret = NULL;
119	int ret_score = 0;
120
121	if (!parent)
122		return NULL;
 
 
 
123
124	list_for_each_entry(adev, &parent->children, node) {
125		unsigned long long addr;
126		acpi_status status;
127		int score;
128
129		status = acpi_evaluate_integer(adev->handle, METHOD_NAME__ADR,
130					       NULL, &addr);
131		if (ACPI_FAILURE(status) || addr != address)
132			continue;
133
134		if (!ret) {
135			/* This is the first matching object.  Save it. */
136			ret = adev;
137			continue;
138		}
139		/*
140		 * There is more than one matching device object with the same
141		 * _ADR value.  That really is unexpected, so we are kind of
142		 * beyond the scope of the spec here.  We have to choose which
143		 * one to return, though.
144		 *
145		 * First, check if the previously found object is good enough
146		 * and return it if so.  Second, do the same for the object that
147		 * we've just found.
148		 */
149		if (!ret_score) {
150			ret_score = find_child_checks(ret, check_children);
151			if (ret_score == FIND_CHILD_MAX_SCORE)
152				return ret;
153		}
154		score = find_child_checks(adev, check_children);
155		if (score == FIND_CHILD_MAX_SCORE) {
156			return adev;
157		} else if (score > ret_score) {
158			ret = adev;
159			ret_score = score;
160		}
161	}
162	return ret;
163}
164EXPORT_SYMBOL_GPL(acpi_find_child_device);
165
166static void acpi_physnode_link_name(char *buf, unsigned int node_id)
 
 
167{
168	if (node_id > 0)
169		snprintf(buf, PHYSICAL_NODE_NAME_SIZE,
170			 PHYSICAL_NODE_STRING "%u", node_id);
171	else
172		strcpy(buf, PHYSICAL_NODE_STRING);
173}
174
175int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
176{
177	struct acpi_device_physical_node *physical_node, *pn;
178	char physical_node_name[PHYSICAL_NODE_NAME_SIZE];
179	struct list_head *physnode_list;
180	unsigned int node_id;
181	int retval = -EINVAL;
182
183	if (has_acpi_companion(dev)) {
184		if (acpi_dev) {
185			dev_warn(dev, "ACPI companion already set\n");
186			return -EINVAL;
187		} else {
188			acpi_dev = ACPI_COMPANION(dev);
189		}
190	}
191	if (!acpi_dev)
 
 
 
192		return -EINVAL;
 
 
193
194	get_device(&acpi_dev->dev);
195	get_device(dev);
196	physical_node = kzalloc(sizeof(*physical_node), GFP_KERNEL);
197	if (!physical_node) {
198		retval = -ENOMEM;
199		goto err;
200	}
201
202	mutex_lock(&acpi_dev->physical_node_lock);
203
204	/*
205	 * Keep the list sorted by node_id so that the IDs of removed nodes can
206	 * be recycled easily.
207	 */
208	physnode_list = &acpi_dev->physical_node_list;
209	node_id = 0;
210	list_for_each_entry(pn, &acpi_dev->physical_node_list, node) {
211		/* Sanity check. */
212		if (pn->dev == dev) {
213			mutex_unlock(&acpi_dev->physical_node_lock);
214
215			dev_warn(dev, "Already associated with ACPI node\n");
216			kfree(physical_node);
217			if (ACPI_COMPANION(dev) != acpi_dev)
218				goto err;
219
220			put_device(dev);
221			put_device(&acpi_dev->dev);
222			return 0;
223		}
224		if (pn->node_id == node_id) {
225			physnode_list = &pn->node;
226			node_id++;
227		}
228	}
229
230	physical_node->node_id = node_id;
231	physical_node->dev = dev;
232	list_add(&physical_node->node, physnode_list);
233	acpi_dev->physical_node_count++;
234
235	if (!has_acpi_companion(dev))
236		ACPI_COMPANION_SET(dev, acpi_dev);
237
238	acpi_physnode_link_name(physical_node_name, node_id);
239	retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
240				   physical_node_name);
241	if (retval)
242		dev_err(&acpi_dev->dev, "Failed to create link %s (%d)\n",
243			physical_node_name, retval);
244
245	retval = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
246				   "firmware_node");
247	if (retval)
248		dev_err(dev, "Failed to create link firmware_node (%d)\n",
249			retval);
250
251	mutex_unlock(&acpi_dev->physical_node_lock);
252
253	if (acpi_dev->wakeup.flags.valid)
254		device_set_wakeup_capable(dev, true);
255
256	return 0;
257
258 err:
259	ACPI_COMPANION_SET(dev, NULL);
260	put_device(dev);
261	put_device(&acpi_dev->dev);
262	return retval;
263}
264EXPORT_SYMBOL_GPL(acpi_bind_one);
265
266int acpi_unbind_one(struct device *dev)
267{
268	struct acpi_device *acpi_dev = ACPI_COMPANION(dev);
269	struct acpi_device_physical_node *entry;
270
271	if (!acpi_dev)
272		return 0;
 
 
273
274	mutex_lock(&acpi_dev->physical_node_lock);
275
276	list_for_each_entry(entry, &acpi_dev->physical_node_list, node)
277		if (entry->dev == dev) {
278			char physnode_name[PHYSICAL_NODE_NAME_SIZE];
279
280			list_del(&entry->node);
281			acpi_dev->physical_node_count--;
282
283			acpi_physnode_link_name(physnode_name, entry->node_id);
284			sysfs_remove_link(&acpi_dev->dev.kobj, physnode_name);
285			sysfs_remove_link(&dev->kobj, "firmware_node");
286			ACPI_COMPANION_SET(dev, NULL);
287			/* Drop references taken by acpi_bind_one(). */
288			put_device(dev);
289			put_device(&acpi_dev->dev);
290			kfree(entry);
291			break;
292		}
293
294	mutex_unlock(&acpi_dev->physical_node_lock);
 
 
 
 
 
 
 
295	return 0;
296}
297EXPORT_SYMBOL_GPL(acpi_unbind_one);
298
299static int acpi_platform_notify(struct device *dev)
300{
301	struct acpi_bus_type *type = acpi_get_bus_type(dev);
302	struct acpi_device *adev;
303	int ret;
304
305	ret = acpi_bind_one(dev, NULL);
306	if (ret && type) {
307		struct acpi_device *adev;
308
309		adev = type->find_companion(dev);
310		if (!adev) {
311			DBG("Unable to get handle for %s\n", dev_name(dev));
312			ret = -ENODEV;
313			goto out;
314		}
315		ret = acpi_bind_one(dev, adev);
316		if (ret)
317			goto out;
318	}
319	adev = ACPI_COMPANION(dev);
320	if (!adev)
321		goto out;
322
323	if (dev->bus == &platform_bus_type)
324		acpi_configure_pmsi_domain(dev);
325
326	if (type && type->setup)
327		type->setup(dev);
328	else if (adev->handler && adev->handler->bind)
329		adev->handler->bind(dev);
330
331 out:
332#if ACPI_GLUE_DEBUG
333	if (!ret) {
334		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
335
336		acpi_get_name(ACPI_HANDLE(dev), ACPI_FULL_PATHNAME, &buffer);
 
337		DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
338		kfree(buffer.pointer);
339	} else
340		DBG("Device %s -> No ACPI support\n", dev_name(dev));
341#endif
342
343	return ret;
344}
345
346static int acpi_platform_notify_remove(struct device *dev)
347{
348	struct acpi_device *adev = ACPI_COMPANION(dev);
349	struct acpi_bus_type *type;
350
351	if (!adev)
352		return 0;
353
354	type = acpi_get_bus_type(dev);
355	if (type && type->cleanup)
356		type->cleanup(dev);
357	else if (adev->handler && adev->handler->unbind)
358		adev->handler->unbind(dev);
359
360	acpi_unbind_one(dev);
361	return 0;
362}
363
364void __init init_acpi_device_notify(void)
365{
366	if (platform_notify || platform_notify_remove) {
367		printk(KERN_ERR PREFIX "Can't use platform_notify\n");
368		return;
369	}
370	platform_notify = acpi_platform_notify;
371	platform_notify_remove = acpi_platform_notify_remove;
 
372}