blob: 2f13eba5d5aebf9c7a9f0930cbc1022bde441f75 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * PCI searching functions.
3 *
4 * Copyright (C) 1993 -- 1997 Drew Eckhardt, Frederic Potter,
5 * David Mosberger-Tang
6 * Copyright (C) 1997 -- 2000 Martin Mares <mj@ucw.cz>
7 * Copyright (C) 2003 -- 2004 Greg Kroah-Hartman <greg@kroah.com>
8 */
9
10#include <linux/init.h>
11#include <linux/pci.h>
12#include <linux/module.h>
13#include <linux/interrupt.h>
14#include "pci.h"
15
Zhang Yanmind71374d2006-06-02 12:35:43 +080016DECLARE_RWSEM(pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -070017
18static struct pci_bus * __devinit
19pci_do_find_bus(struct pci_bus* bus, unsigned char busnr)
20{
21 struct pci_bus* child;
22 struct list_head *tmp;
23
24 if(bus->number == busnr)
25 return bus;
26
27 list_for_each(tmp, &bus->children) {
28 child = pci_do_find_bus(pci_bus_b(tmp), busnr);
29 if(child)
30 return child;
31 }
32 return NULL;
33}
34
35/**
36 * pci_find_bus - locate PCI bus from a given domain and bus number
37 * @domain: number of PCI domain to search
38 * @busnr: number of desired PCI bus
39 *
40 * Given a PCI bus number and domain number, the desired PCI bus is located
41 * in the global list of PCI buses. If the bus is found, a pointer to its
42 * data structure is returned. If no bus is found, %NULL is returned.
43 */
Randy Dunlapc8439cfc2006-07-18 14:33:16 -070044struct pci_bus * pci_find_bus(int domain, int busnr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070045{
46 struct pci_bus *bus = NULL;
47 struct pci_bus *tmp_bus;
48
49 while ((bus = pci_find_next_bus(bus)) != NULL) {
50 if (pci_domain_nr(bus) != domain)
51 continue;
52 tmp_bus = pci_do_find_bus(bus, busnr);
53 if (tmp_bus)
54 return tmp_bus;
55 }
56 return NULL;
57}
58
59/**
60 * pci_find_next_bus - begin or continue searching for a PCI bus
61 * @from: Previous PCI bus found, or %NULL for new search.
62 *
63 * Iterates through the list of known PCI busses. A new search is
Randy Dunlapd75763d2006-07-30 03:03:41 -070064 * initiated by passing %NULL as the @from argument. Otherwise if
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 * @from is not %NULL, searches continue from next device on the
66 * global list.
67 */
68struct pci_bus *
69pci_find_next_bus(const struct pci_bus *from)
70{
71 struct list_head *n;
72 struct pci_bus *b = NULL;
73
74 WARN_ON(in_interrupt());
Zhang Yanmind71374d2006-06-02 12:35:43 +080075 down_read(&pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -070076 n = from ? from->node.next : pci_root_buses.next;
77 if (n != &pci_root_buses)
78 b = pci_bus_b(n);
Zhang Yanmind71374d2006-06-02 12:35:43 +080079 up_read(&pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -070080 return b;
81}
82
83/**
84 * pci_find_slot - locate PCI device from a given PCI slot
85 * @bus: number of PCI bus on which desired PCI device resides
86 * @devfn: encodes number of PCI slot in which the desired PCI
87 * device resides and the logical device number within that slot
88 * in case of multi-function devices.
89 *
90 * Given a PCI bus and slot/function number, the desired PCI device
91 * is located in system global list of PCI devices. If the device
92 * is found, a pointer to its data structure is returned. If no
93 * device is found, %NULL is returned.
94 */
95struct pci_dev *
96pci_find_slot(unsigned int bus, unsigned int devfn)
97{
98 struct pci_dev *dev = NULL;
99
100 while ((dev = pci_find_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
101 if (dev->bus->number == bus && dev->devfn == devfn)
102 return dev;
103 }
104 return NULL;
105}
106
107/**
108 * pci_get_slot - locate PCI device for a given PCI slot
109 * @bus: PCI bus on which desired PCI device resides
110 * @devfn: encodes number of PCI slot in which the desired PCI
111 * device resides and the logical device number within that slot
112 * in case of multi-function devices.
113 *
114 * Given a PCI bus and slot/function number, the desired PCI device
115 * is located in the list of PCI devices.
116 * If the device is found, its reference count is increased and this
117 * function returns a pointer to its data structure. The caller must
118 * decrement the reference count by calling pci_dev_put().
119 * If no device is found, %NULL is returned.
120 */
121struct pci_dev * pci_get_slot(struct pci_bus *bus, unsigned int devfn)
122{
123 struct list_head *tmp;
124 struct pci_dev *dev;
125
126 WARN_ON(in_interrupt());
Zhang Yanmind71374d2006-06-02 12:35:43 +0800127 down_read(&pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128
129 list_for_each(tmp, &bus->devices) {
130 dev = pci_dev_b(tmp);
131 if (dev->devfn == devfn)
132 goto out;
133 }
134
135 dev = NULL;
136 out:
137 pci_dev_get(dev);
Zhang Yanmind71374d2006-06-02 12:35:43 +0800138 up_read(&pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 return dev;
140}
141
142/**
Alan Cox29f3eb62006-10-16 16:20:21 -0700143 * pci_get_bus_and_slot - locate PCI device from a given PCI slot
144 * @bus: number of PCI bus on which desired PCI device resides
145 * @devfn: encodes number of PCI slot in which the desired PCI
146 * device resides and the logical device number within that slot
147 * in case of multi-function devices.
148 *
149 * Given a PCI bus and slot/function number, the desired PCI device
150 * is located in system global list of PCI devices. If the device
151 * is found, a pointer to its data structure is returned. If no
152 * device is found, %NULL is returned. The returned device has its
153 * reference count bumped by one.
154 */
155
156struct pci_dev * pci_get_bus_and_slot(unsigned int bus, unsigned int devfn)
157{
158 struct pci_dev *dev = NULL;
159
160 while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
161 if (dev->bus->number == bus && dev->devfn == devfn)
162 return dev;
163 }
164 return NULL;
165}
166
167/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 * pci_find_subsys - begin or continue searching for a PCI device by vendor/subvendor/device/subdevice id
169 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
170 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
171 * @ss_vendor: PCI subsystem vendor id to match, or %PCI_ANY_ID to match all vendor ids
172 * @ss_device: PCI subsystem device id to match, or %PCI_ANY_ID to match all device ids
173 * @from: Previous PCI device found in search, or %NULL for new search.
174 *
175 * Iterates through the list of known PCI devices. If a PCI device is
Randy Dunlapd75763d2006-07-30 03:03:41 -0700176 * found with a matching @vendor, @device, @ss_vendor and @ss_device, a
177 * pointer to its device structure is returned. Otherwise, %NULL is returned.
178 * A new search is initiated by passing %NULL as the @from argument.
179 * Otherwise if @from is not %NULL, searches continue from next device
180 * on the global list.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 *
Randy Dunlapd75763d2006-07-30 03:03:41 -0700182 * NOTE: Do not use this function any more; use pci_get_subsys() instead, as
183 * the PCI device returned by this function can disappear at any moment in
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184 * time.
185 */
186static struct pci_dev * pci_find_subsys(unsigned int vendor,
187 unsigned int device,
188 unsigned int ss_vendor,
189 unsigned int ss_device,
190 const struct pci_dev *from)
191{
192 struct list_head *n;
193 struct pci_dev *dev;
194
195 WARN_ON(in_interrupt());
Zhang Yanmind71374d2006-06-02 12:35:43 +0800196 down_read(&pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197 n = from ? from->global_list.next : pci_devices.next;
198
199 while (n && (n != &pci_devices)) {
200 dev = pci_dev_g(n);
201 if ((vendor == PCI_ANY_ID || dev->vendor == vendor) &&
202 (device == PCI_ANY_ID || dev->device == device) &&
203 (ss_vendor == PCI_ANY_ID || dev->subsystem_vendor == ss_vendor) &&
204 (ss_device == PCI_ANY_ID || dev->subsystem_device == ss_device))
205 goto exit;
206 n = n->next;
207 }
208 dev = NULL;
209exit:
Zhang Yanmind71374d2006-06-02 12:35:43 +0800210 up_read(&pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 return dev;
212}
213
214/**
215 * pci_find_device - begin or continue searching for a PCI device by vendor/device id
216 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
217 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
218 * @from: Previous PCI device found in search, or %NULL for new search.
219 *
Randy Dunlapd75763d2006-07-30 03:03:41 -0700220 * Iterates through the list of known PCI devices. If a PCI device is found
221 * with a matching @vendor and @device, a pointer to its device structure is
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 * returned. Otherwise, %NULL is returned.
Randy Dunlapd75763d2006-07-30 03:03:41 -0700223 * A new search is initiated by passing %NULL as the @from argument.
224 * Otherwise if @from is not %NULL, searches continue from next device
225 * on the global list.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 *
Randy Dunlapd75763d2006-07-30 03:03:41 -0700227 * NOTE: Do not use this function any more; use pci_get_device() instead, as
228 * the PCI device returned by this function can disappear at any moment in
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229 * time.
230 */
231struct pci_dev *
232pci_find_device(unsigned int vendor, unsigned int device, const struct pci_dev *from)
233{
234 return pci_find_subsys(vendor, device, PCI_ANY_ID, PCI_ANY_ID, from);
235}
236
237/**
238 * pci_get_subsys - begin or continue searching for a PCI device by vendor/subvendor/device/subdevice id
239 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
240 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
241 * @ss_vendor: PCI subsystem vendor id to match, or %PCI_ANY_ID to match all vendor ids
242 * @ss_device: PCI subsystem device id to match, or %PCI_ANY_ID to match all device ids
243 * @from: Previous PCI device found in search, or %NULL for new search.
244 *
Randy Dunlapd75763d2006-07-30 03:03:41 -0700245 * Iterates through the list of known PCI devices. If a PCI device is found
246 * with a matching @vendor, @device, @ss_vendor and @ss_device, a pointer to its
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247 * device structure is returned, and the reference count to the device is
248 * incremented. Otherwise, %NULL is returned. A new search is initiated by
Randy Dunlapd75763d2006-07-30 03:03:41 -0700249 * passing %NULL as the @from argument. Otherwise if @from is not %NULL,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 * searches continue from next device on the global list.
251 * The reference count for @from is always decremented if it is not %NULL.
252 */
253struct pci_dev *
254pci_get_subsys(unsigned int vendor, unsigned int device,
255 unsigned int ss_vendor, unsigned int ss_device,
256 struct pci_dev *from)
257{
258 struct list_head *n;
259 struct pci_dev *dev;
260
261 WARN_ON(in_interrupt());
Zhang Yanmind71374d2006-06-02 12:35:43 +0800262 down_read(&pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263 n = from ? from->global_list.next : pci_devices.next;
264
265 while (n && (n != &pci_devices)) {
266 dev = pci_dev_g(n);
267 if ((vendor == PCI_ANY_ID || dev->vendor == vendor) &&
268 (device == PCI_ANY_ID || dev->device == device) &&
269 (ss_vendor == PCI_ANY_ID || dev->subsystem_vendor == ss_vendor) &&
270 (ss_device == PCI_ANY_ID || dev->subsystem_device == ss_device))
271 goto exit;
272 n = n->next;
273 }
274 dev = NULL;
275exit:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 dev = pci_dev_get(dev);
Zhang Yanmind71374d2006-06-02 12:35:43 +0800277 up_read(&pci_bus_sem);
Alan Sternb89b7ea2006-02-23 17:12:51 -0500278 pci_dev_put(from);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 return dev;
280}
281
282/**
283 * pci_get_device - begin or continue searching for a PCI device by vendor/device id
284 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
285 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
286 * @from: Previous PCI device found in search, or %NULL for new search.
287 *
288 * Iterates through the list of known PCI devices. If a PCI device is
289 * found with a matching @vendor and @device, the reference count to the
290 * device is incremented and a pointer to its device structure is returned.
291 * Otherwise, %NULL is returned. A new search is initiated by passing %NULL
Randy Dunlapd75763d2006-07-30 03:03:41 -0700292 * as the @from argument. Otherwise if @from is not %NULL, searches continue
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 * from next device on the global list. The reference count for @from is
294 * always decremented if it is not %NULL.
295 */
296struct pci_dev *
297pci_get_device(unsigned int vendor, unsigned int device, struct pci_dev *from)
298{
299 return pci_get_subsys(vendor, device, PCI_ANY_ID, PCI_ANY_ID, from);
300}
301
Alan Cox29f3eb62006-10-16 16:20:21 -0700302/**
303 * pci_get_device_reverse - begin or continue searching for a PCI device by vendor/device id
304 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
305 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
306 * @from: Previous PCI device found in search, or %NULL for new search.
307 *
308 * Iterates through the list of known PCI devices in the reverse order of
309 * pci_get_device.
310 * If a PCI device is found with a matching @vendor and @device, the reference
311 * count to the device is incremented and a pointer to its device structure
312 * is returned Otherwise, %NULL is returned. A new search is initiated by
313 * passing %NULL as the @from argument. Otherwise if @from is not %NULL,
314 * searches continue from next device on the global list. The reference
315 * count for @from is always decremented if it is not %NULL.
316 */
317struct pci_dev *
318pci_get_device_reverse(unsigned int vendor, unsigned int device, struct pci_dev *from)
319{
320 struct list_head *n;
321 struct pci_dev *dev;
322
323 WARN_ON(in_interrupt());
324 down_read(&pci_bus_sem);
325 n = from ? from->global_list.prev : pci_devices.prev;
326
327 while (n && (n != &pci_devices)) {
328 dev = pci_dev_g(n);
329 if ((vendor == PCI_ANY_ID || dev->vendor == vendor) &&
330 (device == PCI_ANY_ID || dev->device == device))
331 goto exit;
332 n = n->prev;
333 }
334 dev = NULL;
335exit:
336 dev = pci_dev_get(dev);
337 up_read(&pci_bus_sem);
338 pci_dev_put(from);
339 return dev;
340}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341
342/**
343 * pci_find_device_reverse - begin or continue searching for a PCI device by vendor/device id
344 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
345 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
346 * @from: Previous PCI device found in search, or %NULL for new search.
347 *
Randy Dunlapd75763d2006-07-30 03:03:41 -0700348 * Iterates through the list of known PCI devices in the reverse order of
349 * pci_find_device().
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 * If a PCI device is found with a matching @vendor and @device, a pointer to
351 * its device structure is returned. Otherwise, %NULL is returned.
Randy Dunlapd75763d2006-07-30 03:03:41 -0700352 * A new search is initiated by passing %NULL as the @from argument.
353 * Otherwise if @from is not %NULL, searches continue from previous device
354 * on the global list.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 */
356struct pci_dev *
357pci_find_device_reverse(unsigned int vendor, unsigned int device, const struct pci_dev *from)
358{
359 struct list_head *n;
360 struct pci_dev *dev;
361
362 WARN_ON(in_interrupt());
Zhang Yanmind71374d2006-06-02 12:35:43 +0800363 down_read(&pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 n = from ? from->global_list.prev : pci_devices.prev;
365
366 while (n && (n != &pci_devices)) {
367 dev = pci_dev_g(n);
368 if ((vendor == PCI_ANY_ID || dev->vendor == vendor) &&
369 (device == PCI_ANY_ID || dev->device == device))
370 goto exit;
371 n = n->prev;
372 }
373 dev = NULL;
374exit:
Zhang Yanmind71374d2006-06-02 12:35:43 +0800375 up_read(&pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376 return dev;
377}
378
379/**
380 * pci_get_class - begin or continue searching for a PCI device by class
381 * @class: search for a PCI device with this class designation
382 * @from: Previous PCI device found in search, or %NULL for new search.
383 *
384 * Iterates through the list of known PCI devices. If a PCI device is
385 * found with a matching @class, the reference count to the device is
386 * incremented and a pointer to its device structure is returned.
387 * Otherwise, %NULL is returned.
Randy Dunlapd75763d2006-07-30 03:03:41 -0700388 * A new search is initiated by passing %NULL as the @from argument.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389 * Otherwise if @from is not %NULL, searches continue from next device
390 * on the global list. The reference count for @from is always decremented
391 * if it is not %NULL.
392 */
393struct pci_dev *pci_get_class(unsigned int class, struct pci_dev *from)
394{
395 struct list_head *n;
396 struct pci_dev *dev;
397
398 WARN_ON(in_interrupt());
Zhang Yanmind71374d2006-06-02 12:35:43 +0800399 down_read(&pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 n = from ? from->global_list.next : pci_devices.next;
401
402 while (n && (n != &pci_devices)) {
403 dev = pci_dev_g(n);
404 if (dev->class == class)
405 goto exit;
406 n = n->next;
407 }
408 dev = NULL;
409exit:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 dev = pci_dev_get(dev);
Zhang Yanmind71374d2006-06-02 12:35:43 +0800411 up_read(&pci_bus_sem);
Alan Sternb89b7ea2006-02-23 17:12:51 -0500412 pci_dev_put(from);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413 return dev;
414}
415
416/**
417 * pci_dev_present - Returns 1 if device matching the device list is present, 0 if not.
418 * @ids: A pointer to a null terminated list of struct pci_device_id structures
419 * that describe the type of PCI device the caller is trying to find.
420 *
421 * Obvious fact: You do not have a reference to any device that might be found
422 * by this function, so if that device is removed from the system right after
423 * this function is finished, the value will be stale. Use this function to
424 * find devices that are usually built into a system, or for a general hint as
425 * to if another device happens to be present at this specific moment in time.
426 */
427int pci_dev_present(const struct pci_device_id *ids)
428{
429 struct pci_dev *dev;
430 int found = 0;
431
432 WARN_ON(in_interrupt());
Zhang Yanmind71374d2006-06-02 12:35:43 +0800433 down_read(&pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 while (ids->vendor || ids->subvendor || ids->class_mask) {
435 list_for_each_entry(dev, &pci_devices, global_list) {
436 if (pci_match_one_device(ids, dev)) {
437 found = 1;
438 goto exit;
439 }
440 }
441 ids++;
442 }
Zhang Yanmind71374d2006-06-02 12:35:43 +0800443exit:
444 up_read(&pci_bus_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445 return found;
446}
447EXPORT_SYMBOL(pci_dev_present);
448
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449EXPORT_SYMBOL(pci_find_device);
450EXPORT_SYMBOL(pci_find_device_reverse);
451EXPORT_SYMBOL(pci_find_slot);
Alan Cox29f3eb62006-10-16 16:20:21 -0700452/* For boot time work */
453EXPORT_SYMBOL(pci_find_bus);
454EXPORT_SYMBOL(pci_find_next_bus);
455/* For everyone */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456EXPORT_SYMBOL(pci_get_device);
Alan Cox29f3eb62006-10-16 16:20:21 -0700457EXPORT_SYMBOL(pci_get_device_reverse);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458EXPORT_SYMBOL(pci_get_subsys);
459EXPORT_SYMBOL(pci_get_slot);
Alan Cox29f3eb62006-10-16 16:20:21 -0700460EXPORT_SYMBOL(pci_get_bus_and_slot);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461EXPORT_SYMBOL(pci_get_class);