2 * PCI searching functions.
4 * Copyright (C) 1993 -- 1997 Drew Eckhardt, Frederic Potter,
6 * Copyright (C) 1997 -- 2000 Martin Mares <mj@ucw.cz>
7 * Copyright (C) 2003 -- 2004 Greg Kroah-Hartman <greg@kroah.com>
10 #include <linux/init.h>
11 #include <linux/pci.h>
12 #include <linux/module.h>
13 #include <linux/interrupt.h>
16 DECLARE_RWSEM(pci_bus_sem
);
18 static struct pci_bus
* __devinit
19 pci_do_find_bus(struct pci_bus
* bus
, unsigned char busnr
)
21 struct pci_bus
* child
;
22 struct list_head
*tmp
;
24 if(bus
->number
== busnr
)
27 list_for_each(tmp
, &bus
->children
) {
28 child
= pci_do_find_bus(pci_bus_b(tmp
), busnr
);
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
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.
44 struct pci_bus
* pci_find_bus(int domain
, int busnr
)
46 struct pci_bus
*bus
= NULL
;
47 struct pci_bus
*tmp_bus
;
49 while ((bus
= pci_find_next_bus(bus
)) != NULL
) {
50 if (pci_domain_nr(bus
) != domain
)
52 tmp_bus
= pci_do_find_bus(bus
, busnr
);
60 * pci_find_next_bus - begin or continue searching for a PCI bus
61 * @from: Previous PCI bus found, or %NULL for new search.
63 * Iterates through the list of known PCI busses. A new search is
64 * initiated by passing %NULL as the @from argument. Otherwise if
65 * @from is not %NULL, searches continue from next device on the
69 pci_find_next_bus(const struct pci_bus
*from
)
72 struct pci_bus
*b
= NULL
;
74 WARN_ON(in_interrupt());
75 down_read(&pci_bus_sem
);
76 n
= from
? from
->node
.next
: pci_root_buses
.next
;
77 if (n
!= &pci_root_buses
)
79 up_read(&pci_bus_sem
);
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.
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.
96 pci_find_slot(unsigned int bus
, unsigned int devfn
)
98 struct pci_dev
*dev
= NULL
;
100 while ((dev
= pci_find_device(PCI_ANY_ID
, PCI_ANY_ID
, dev
)) != NULL
) {
101 if (dev
->bus
->number
== bus
&& dev
->devfn
== devfn
)
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.
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.
121 struct pci_dev
* pci_get_slot(struct pci_bus
*bus
, unsigned int devfn
)
123 struct list_head
*tmp
;
126 WARN_ON(in_interrupt());
127 down_read(&pci_bus_sem
);
129 list_for_each(tmp
, &bus
->devices
) {
130 dev
= pci_dev_b(tmp
);
131 if (dev
->devfn
== devfn
)
138 up_read(&pci_bus_sem
);
143 * 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.
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.
156 struct pci_dev
* pci_get_bus_and_slot(unsigned int bus
, unsigned int devfn
)
158 struct pci_dev
*dev
= NULL
;
160 while ((dev
= pci_get_device(PCI_ANY_ID
, PCI_ANY_ID
, dev
)) != NULL
) {
161 if (dev
->bus
->number
== bus
&& dev
->devfn
== devfn
)
168 * 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.
175 * Iterates through the list of known PCI devices. If a PCI device is
176 * 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.
182 * 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
186 static struct pci_dev
* pci_find_subsys(unsigned int vendor
,
188 unsigned int ss_vendor
,
189 unsigned int ss_device
,
190 const struct pci_dev
*from
)
195 WARN_ON(in_interrupt());
198 * pci_find_subsys() can be called on the ide_setup() path, super-early
199 * in boot. But the down_read() will enable local interrupts, which
200 * can cause some machines to crash. So here we detect and flag that
201 * situation and bail out early.
203 if (unlikely(list_empty(&pci_devices
)))
205 down_read(&pci_bus_sem
);
206 n
= from
? from
->global_list
.next
: pci_devices
.next
;
208 while (n
&& (n
!= &pci_devices
)) {
210 if ((vendor
== PCI_ANY_ID
|| dev
->vendor
== vendor
) &&
211 (device
== PCI_ANY_ID
|| dev
->device
== device
) &&
212 (ss_vendor
== PCI_ANY_ID
|| dev
->subsystem_vendor
== ss_vendor
) &&
213 (ss_device
== PCI_ANY_ID
|| dev
->subsystem_device
== ss_device
))
219 up_read(&pci_bus_sem
);
224 * pci_find_device - begin or continue searching for a PCI device by vendor/device id
225 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
226 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
227 * @from: Previous PCI device found in search, or %NULL for new search.
229 * Iterates through the list of known PCI devices. If a PCI device is found
230 * with a matching @vendor and @device, a pointer to its device structure is
231 * returned. Otherwise, %NULL is returned.
232 * A new search is initiated by passing %NULL as the @from argument.
233 * Otherwise if @from is not %NULL, searches continue from next device
234 * on the global list.
236 * NOTE: Do not use this function any more; use pci_get_device() instead, as
237 * the PCI device returned by this function can disappear at any moment in
241 pci_find_device(unsigned int vendor
, unsigned int device
, const struct pci_dev
*from
)
243 return pci_find_subsys(vendor
, device
, PCI_ANY_ID
, PCI_ANY_ID
, from
);
247 * pci_get_subsys - begin or continue searching for a PCI device by vendor/subvendor/device/subdevice id
248 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
249 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
250 * @ss_vendor: PCI subsystem vendor id to match, or %PCI_ANY_ID to match all vendor ids
251 * @ss_device: PCI subsystem device id to match, or %PCI_ANY_ID to match all device ids
252 * @from: Previous PCI device found in search, or %NULL for new search.
254 * Iterates through the list of known PCI devices. If a PCI device is found
255 * with a matching @vendor, @device, @ss_vendor and @ss_device, a pointer to its
256 * device structure is returned, and the reference count to the device is
257 * incremented. Otherwise, %NULL is returned. A new search is initiated by
258 * passing %NULL as the @from argument. Otherwise if @from is not %NULL,
259 * searches continue from next device on the global list.
260 * The reference count for @from is always decremented if it is not %NULL.
263 pci_get_subsys(unsigned int vendor
, unsigned int device
,
264 unsigned int ss_vendor
, unsigned int ss_device
,
265 struct pci_dev
*from
)
270 WARN_ON(in_interrupt());
273 * pci_get_subsys() can potentially be called by drivers super-early
274 * in boot. But the down_read() will enable local interrupts, which
275 * can cause some machines to crash. So here we detect and flag that
276 * situation and bail out early.
278 if (unlikely(list_empty(&pci_devices
)))
280 down_read(&pci_bus_sem
);
281 n
= from
? from
->global_list
.next
: pci_devices
.next
;
283 while (n
&& (n
!= &pci_devices
)) {
285 if ((vendor
== PCI_ANY_ID
|| dev
->vendor
== vendor
) &&
286 (device
== PCI_ANY_ID
|| dev
->device
== device
) &&
287 (ss_vendor
== PCI_ANY_ID
|| dev
->subsystem_vendor
== ss_vendor
) &&
288 (ss_device
== PCI_ANY_ID
|| dev
->subsystem_device
== ss_device
))
294 dev
= pci_dev_get(dev
);
295 up_read(&pci_bus_sem
);
301 * pci_get_device - begin or continue searching for a PCI device by vendor/device id
302 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
303 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
304 * @from: Previous PCI device found in search, or %NULL for new search.
306 * Iterates through the list of known PCI devices. If a PCI device is
307 * found with a matching @vendor and @device, the reference count to the
308 * device is incremented and a pointer to its device structure is returned.
309 * Otherwise, %NULL is returned. A new search is initiated by passing %NULL
310 * as the @from argument. Otherwise if @from is not %NULL, searches continue
311 * from next device on the global list. The reference count for @from is
312 * always decremented if it is not %NULL.
315 pci_get_device(unsigned int vendor
, unsigned int device
, struct pci_dev
*from
)
317 return pci_get_subsys(vendor
, device
, PCI_ANY_ID
, PCI_ANY_ID
, from
);
321 * pci_get_device_reverse - begin or continue searching for a PCI device by vendor/device id
322 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
323 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
324 * @from: Previous PCI device found in search, or %NULL for new search.
326 * Iterates through the list of known PCI devices in the reverse order of
328 * If a PCI device is found with a matching @vendor and @device, the reference
329 * count to the device is incremented and a pointer to its device structure
330 * is returned Otherwise, %NULL is returned. A new search is initiated by
331 * passing %NULL as the @from argument. Otherwise if @from is not %NULL,
332 * searches continue from next device on the global list. The reference
333 * count for @from is always decremented if it is not %NULL.
336 pci_get_device_reverse(unsigned int vendor
, unsigned int device
, struct pci_dev
*from
)
341 WARN_ON(in_interrupt());
342 down_read(&pci_bus_sem
);
343 n
= from
? from
->global_list
.prev
: pci_devices
.prev
;
345 while (n
&& (n
!= &pci_devices
)) {
347 if ((vendor
== PCI_ANY_ID
|| dev
->vendor
== vendor
) &&
348 (device
== PCI_ANY_ID
|| dev
->device
== device
))
354 dev
= pci_dev_get(dev
);
355 up_read(&pci_bus_sem
);
361 * pci_find_device_reverse - begin or continue searching for a PCI device by vendor/device id
362 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
363 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
364 * @from: Previous PCI device found in search, or %NULL for new search.
366 * Iterates through the list of known PCI devices in the reverse order of
368 * If a PCI device is found with a matching @vendor and @device, a pointer to
369 * its device structure is returned. Otherwise, %NULL is returned.
370 * A new search is initiated by passing %NULL as the @from argument.
371 * Otherwise if @from is not %NULL, searches continue from previous device
372 * on the global list.
375 pci_find_device_reverse(unsigned int vendor
, unsigned int device
, const struct pci_dev
*from
)
380 WARN_ON(in_interrupt());
381 down_read(&pci_bus_sem
);
382 n
= from
? from
->global_list
.prev
: pci_devices
.prev
;
384 while (n
&& (n
!= &pci_devices
)) {
386 if ((vendor
== PCI_ANY_ID
|| dev
->vendor
== vendor
) &&
387 (device
== PCI_ANY_ID
|| dev
->device
== device
))
393 up_read(&pci_bus_sem
);
398 * pci_get_class - begin or continue searching for a PCI device by class
399 * @class: search for a PCI device with this class designation
400 * @from: Previous PCI device found in search, or %NULL for new search.
402 * Iterates through the list of known PCI devices. If a PCI device is
403 * found with a matching @class, the reference count to the device is
404 * incremented and a pointer to its device structure is returned.
405 * Otherwise, %NULL is returned.
406 * A new search is initiated by passing %NULL as the @from argument.
407 * Otherwise if @from is not %NULL, searches continue from next device
408 * on the global list. The reference count for @from is always decremented
409 * if it is not %NULL.
411 struct pci_dev
*pci_get_class(unsigned int class, struct pci_dev
*from
)
416 WARN_ON(in_interrupt());
417 down_read(&pci_bus_sem
);
418 n
= from
? from
->global_list
.next
: pci_devices
.next
;
420 while (n
&& (n
!= &pci_devices
)) {
422 if (dev
->class == class)
428 dev
= pci_dev_get(dev
);
429 up_read(&pci_bus_sem
);
434 const struct pci_device_id
*pci_find_present(const struct pci_device_id
*ids
)
437 const struct pci_device_id
*found
= NULL
;
439 WARN_ON(in_interrupt());
440 down_read(&pci_bus_sem
);
441 while (ids
->vendor
|| ids
->subvendor
|| ids
->class_mask
) {
442 list_for_each_entry(dev
, &pci_devices
, global_list
) {
443 if ((found
= pci_match_one_device(ids
, dev
)) != NULL
)
448 up_read(&pci_bus_sem
);
453 * pci_dev_present - Returns 1 if device matching the device list is present, 0 if not.
454 * @ids: A pointer to a null terminated list of struct pci_device_id structures
455 * that describe the type of PCI device the caller is trying to find.
457 * Obvious fact: You do not have a reference to any device that might be found
458 * by this function, so if that device is removed from the system right after
459 * this function is finished, the value will be stale. Use this function to
460 * find devices that are usually built into a system, or for a general hint as
461 * to if another device happens to be present at this specific moment in time.
463 int pci_dev_present(const struct pci_device_id
*ids
)
465 return pci_find_present(ids
) == NULL
? 0 : 1;
468 EXPORT_SYMBOL(pci_dev_present
);
469 EXPORT_SYMBOL(pci_find_present
);
471 EXPORT_SYMBOL(pci_find_device
);
472 EXPORT_SYMBOL(pci_find_device_reverse
);
473 EXPORT_SYMBOL(pci_find_slot
);
474 /* For boot time work */
475 EXPORT_SYMBOL(pci_find_bus
);
476 EXPORT_SYMBOL(pci_find_next_bus
);
478 EXPORT_SYMBOL(pci_get_device
);
479 EXPORT_SYMBOL(pci_get_device_reverse
);
480 EXPORT_SYMBOL(pci_get_subsys
);
481 EXPORT_SYMBOL(pci_get_slot
);
482 EXPORT_SYMBOL(pci_get_bus_and_slot
);
483 EXPORT_SYMBOL(pci_get_class
);