summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/glue.c
blob: 94672297e1b1bc6f3b482b3e0985cda28786ee10 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
/*
 * 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_device) {
		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;
}

static acpi_status acpi_dev_present(acpi_handle handle, u32 lvl_not_used,
				  void *not_used, void **ret_p)
{
	struct acpi_device *adev = NULL;

	acpi_bus_get_device(handle, &adev);
	if (adev) {
		*ret_p = handle;
		return AE_CTRL_TERMINATE;
	}
	return AE_OK;
}

static bool acpi_extra_checks_passed(acpi_handle handle, bool is_bridge)
{
	unsigned long long sta;
	acpi_status status;

	status = acpi_bus_get_status_handle(handle, &sta);
	if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_ENABLED))
		return false;

	if (is_bridge) {
		void *test = NULL;

		/* Check if this object has at least one child device. */
		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
				    acpi_dev_present, NULL, NULL, &test);
		return !!test;
	}
	return true;
}

struct find_child_context {
	u64 addr;
	bool is_bridge;
	acpi_handle ret;
	bool ret_checked;
};

static acpi_status do_find_child(acpi_handle handle, u32 lvl_not_used,
				 void *data, void **not_used)
{
	struct find_child_context *context = data;
	unsigned long long addr;
	acpi_status status;

	status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &addr);
	if (ACPI_FAILURE(status) || addr != context->addr)
		return AE_OK;

	if (!context->ret) {
		/* This is the first matching object.  Save its handle. */
		context->ret = handle;
		return AE_OK;
	}
	/*
	 * There is more than one matching 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
	 * its handle if so.  Second, check the same for the object that we've
	 * just found.
	 */
	if (!context->ret_checked) {
		if (acpi_extra_checks_passed(context->ret, context->is_bridge))
			return AE_CTRL_TERMINATE;
		else
			context->ret_checked = true;
	}
	if (acpi_extra_checks_passed(handle, context->is_bridge)) {
		context->ret = handle;
		return AE_CTRL_TERMINATE;
	}
	return AE_OK;
}

acpi_handle acpi_find_child(acpi_handle parent, u64 addr, bool is_bridge)
{
	if (parent) {
		struct find_child_context context = {
			.addr = addr,
			.is_bridge = is_bridge,
		};

		acpi_walk_namespace(ACPI_TYPE_DEVICE, parent, 1, do_find_child,
				    NULL, &context, NULL);
		return context.ret;
	}
	return NULL;
}
EXPORT_SYMBOL_GPL(acpi_find_child);

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, acpi_handle handle)
{
	struct acpi_device *acpi_dev;
	acpi_status status;
	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_HANDLE(dev)) {
		if (handle) {
			dev_warn(dev, "ACPI handle is already set\n");
			return -EINVAL;
		} else {
			handle = ACPI_HANDLE(dev);
		}
	}
	if (!handle)
		return -EINVAL;

	get_device(dev);
	status = acpi_bus_get_device(handle, &acpi_dev);
	if (ACPI_FAILURE(status))
		goto err;

	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_HANDLE(dev) != handle)
				goto err;

			put_device(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_HANDLE(dev))
		ACPI_HANDLE_SET(dev, acpi_dev->handle);

	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_HANDLE_SET(dev, NULL);
	put_device(dev);
	return retval;
}
EXPORT_SYMBOL_GPL(acpi_bind_one);

int acpi_unbind_one(struct device *dev)
{
	struct acpi_device_physical_node *entry;
	struct acpi_device *acpi_dev;
	acpi_status status;

	if (!ACPI_HANDLE(dev))
		return 0;

	status = acpi_bus_get_device(ACPI_HANDLE(dev), &acpi_dev);
	if (ACPI_FAILURE(status)) {
		dev_err(dev, "Oops, ACPI handle corrupt in %s()\n", __func__);
		return -EINVAL;
	}

	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_HANDLE_SET(dev, NULL);
			/* acpi_bind_one() increase refcnt by one. */
			put_device(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);
	acpi_handle handle;
	int ret;

	ret = acpi_bind_one(dev, NULL);
	if (ret && type) {
		ret = type->find_device(dev, &handle);
		if (ret) {
			DBG("Unable to get handle for %s\n", dev_name(dev));
			goto out;
		}
		ret = acpi_bind_one(dev, handle);
		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;
}