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
*pci_do_find_bus(struct pci_bus
*bus
, unsigned char busnr
)
20 struct pci_bus
* child
;
21 struct list_head
*tmp
;
23 if(bus
->number
== busnr
)
26 list_for_each(tmp
, &bus
->children
) {
27 child
= pci_do_find_bus(pci_bus_b(tmp
), busnr
);
35 * pci_find_bus - locate PCI bus from a given domain and bus number
36 * @domain: number of PCI domain to search
37 * @busnr: number of desired PCI bus
39 * Given a PCI bus number and domain number, the desired PCI bus is located
40 * in the global list of PCI buses. If the bus is found, a pointer to its
41 * data structure is returned. If no bus is found, %NULL is returned.
43 struct pci_bus
* pci_find_bus(int domain
, int busnr
)
45 struct pci_bus
*bus
= NULL
;
46 struct pci_bus
*tmp_bus
;
48 while ((bus
= pci_find_next_bus(bus
)) != NULL
) {
49 if (pci_domain_nr(bus
) != domain
)
51 tmp_bus
= pci_do_find_bus(bus
, busnr
);
59 * pci_find_next_bus - begin or continue searching for a PCI bus
60 * @from: Previous PCI bus found, or %NULL for new search.
62 * Iterates through the list of known PCI busses. A new search is
63 * initiated by passing %NULL as the @from argument. Otherwise if
64 * @from is not %NULL, searches continue from next device on the
68 pci_find_next_bus(const struct pci_bus
*from
)
71 struct pci_bus
*b
= NULL
;
73 WARN_ON(in_interrupt());
74 down_read(&pci_bus_sem
);
75 n
= from
? from
->node
.next
: pci_root_buses
.next
;
76 if (n
!= &pci_root_buses
)
78 up_read(&pci_bus_sem
);
83 * pci_find_slot - locate PCI device from a given PCI slot
84 * @bus: number of PCI bus on which desired PCI device resides
85 * @devfn: encodes number of PCI slot in which the desired PCI
86 * device resides and the logical device number within that slot
87 * in case of multi-function devices.
89 * Given a PCI bus and slot/function number, the desired PCI device
90 * is located in system global list of PCI devices. If the device
91 * is found, a pointer to its data structure is returned. If no
92 * device is found, %NULL is returned.
95 pci_find_slot(unsigned int bus
, unsigned int devfn
)
97 struct pci_dev
*dev
= NULL
;
99 while ((dev
= pci_find_device(PCI_ANY_ID
, PCI_ANY_ID
, dev
)) != NULL
) {
100 if (dev
->bus
->number
== bus
&& dev
->devfn
== devfn
)
107 * pci_get_slot - locate PCI device for a given PCI slot
108 * @bus: PCI bus on which desired PCI device resides
109 * @devfn: encodes number of PCI slot in which the desired PCI
110 * device resides and the logical device number within that slot
111 * in case of multi-function devices.
113 * Given a PCI bus and slot/function number, the desired PCI device
114 * is located in the list of PCI devices.
115 * If the device is found, its reference count is increased and this
116 * function returns a pointer to its data structure. The caller must
117 * decrement the reference count by calling pci_dev_put().
118 * If no device is found, %NULL is returned.
120 struct pci_dev
* pci_get_slot(struct pci_bus
*bus
, unsigned int devfn
)
122 struct list_head
*tmp
;
125 WARN_ON(in_interrupt());
126 down_read(&pci_bus_sem
);
128 list_for_each(tmp
, &bus
->devices
) {
129 dev
= pci_dev_b(tmp
);
130 if (dev
->devfn
== devfn
)
137 up_read(&pci_bus_sem
);
142 * pci_get_bus_and_slot - locate PCI device from a given PCI slot
143 * @bus: number of PCI bus on which desired PCI device resides
144 * @devfn: encodes number of PCI slot in which the desired PCI
145 * device resides and the logical device number within that slot
146 * in case of multi-function devices.
148 * Given a PCI bus and slot/function number, the desired PCI device
149 * is located in system global list of PCI devices. If the device
150 * is found, a pointer to its data structure is returned. If no
151 * device is found, %NULL is returned. The returned device has its
152 * reference count bumped by one.
155 struct pci_dev
* pci_get_bus_and_slot(unsigned int bus
, unsigned int devfn
)
157 struct pci_dev
*dev
= NULL
;
159 while ((dev
= pci_get_device(PCI_ANY_ID
, PCI_ANY_ID
, dev
)) != NULL
) {
160 if (dev
->bus
->number
== bus
&& dev
->devfn
== devfn
)
167 * pci_find_subsys - begin or continue searching for a PCI device by vendor/subvendor/device/subdevice id
168 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
169 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
170 * @ss_vendor: PCI subsystem vendor id to match, or %PCI_ANY_ID to match all vendor ids
171 * @ss_device: PCI subsystem device id to match, or %PCI_ANY_ID to match all device ids
172 * @from: Previous PCI device found in search, or %NULL for new search.
174 * Iterates through the list of known PCI devices. If a PCI device is
175 * found with a matching @vendor, @device, @ss_vendor and @ss_device, a
176 * pointer to its device structure is returned. Otherwise, %NULL is returned.
177 * A new search is initiated by passing %NULL as the @from argument.
178 * Otherwise if @from is not %NULL, searches continue from next device
179 * on the global list.
181 * NOTE: Do not use this function any more; use pci_get_subsys() instead, as
182 * the PCI device returned by this function can disappear at any moment in
185 static struct pci_dev
* pci_find_subsys(unsigned int vendor
,
187 unsigned int ss_vendor
,
188 unsigned int ss_device
,
189 const struct pci_dev
*from
)
194 WARN_ON(in_interrupt());
197 * pci_find_subsys() can be called on the ide_setup() path, super-early
198 * in boot. But the down_read() will enable local interrupts, which
199 * can cause some machines to crash. So here we detect and flag that
200 * situation and bail out early.
202 if (unlikely(list_empty(&pci_devices
)))
204 down_read(&pci_bus_sem
);
205 n
= from
? from
->global_list
.next
: pci_devices
.next
;
207 while (n
&& (n
!= &pci_devices
)) {
209 if ((vendor
== PCI_ANY_ID
|| dev
->vendor
== vendor
) &&
210 (device
== PCI_ANY_ID
|| dev
->device
== device
) &&
211 (ss_vendor
== PCI_ANY_ID
|| dev
->subsystem_vendor
== ss_vendor
) &&
212 (ss_device
== PCI_ANY_ID
|| dev
->subsystem_device
== ss_device
))
218 up_read(&pci_bus_sem
);
223 * pci_find_device - begin or continue searching for a PCI device by vendor/device id
224 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
225 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
226 * @from: Previous PCI device found in search, or %NULL for new search.
228 * Iterates through the list of known PCI devices. If a PCI device is found
229 * with a matching @vendor and @device, a pointer to its device structure is
230 * returned. Otherwise, %NULL is returned.
231 * A new search is initiated by passing %NULL as the @from argument.
232 * Otherwise if @from is not %NULL, searches continue from next device
233 * on the global list.
235 * NOTE: Do not use this function any more; use pci_get_device() instead, as
236 * the PCI device returned by this function can disappear at any moment in
240 pci_find_device(unsigned int vendor
, unsigned int device
, const struct pci_dev
*from
)
242 return pci_find_subsys(vendor
, device
, PCI_ANY_ID
, PCI_ANY_ID
, from
);
246 * pci_get_subsys - begin or continue searching for a PCI device by vendor/subvendor/device/subdevice id
247 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
248 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
249 * @ss_vendor: PCI subsystem vendor id to match, or %PCI_ANY_ID to match all vendor ids
250 * @ss_device: PCI subsystem device id to match, or %PCI_ANY_ID to match all device ids
251 * @from: Previous PCI device found in search, or %NULL for new search.
253 * Iterates through the list of known PCI devices. If a PCI device is found
254 * with a matching @vendor, @device, @ss_vendor and @ss_device, a pointer to its
255 * device structure is returned, and the reference count to the device is
256 * incremented. Otherwise, %NULL is returned. A new search is initiated by
257 * passing %NULL as the @from argument. Otherwise if @from is not %NULL,
258 * searches continue from next device on the global list.
259 * The reference count for @from is always decremented if it is not %NULL.
262 pci_get_subsys(unsigned int vendor
, unsigned int device
,
263 unsigned int ss_vendor
, unsigned int ss_device
,
264 struct pci_dev
*from
)
269 WARN_ON(in_interrupt());
272 * pci_get_subsys() can potentially be called by drivers super-early
273 * in boot. But the down_read() will enable local interrupts, which
274 * can cause some machines to crash. So here we detect and flag that
275 * situation and bail out early.
277 if (unlikely(list_empty(&pci_devices
)))
279 down_read(&pci_bus_sem
);
280 n
= from
? from
->global_list
.next
: pci_devices
.next
;
282 while (n
&& (n
!= &pci_devices
)) {
284 if ((vendor
== PCI_ANY_ID
|| dev
->vendor
== vendor
) &&
285 (device
== PCI_ANY_ID
|| dev
->device
== device
) &&
286 (ss_vendor
== PCI_ANY_ID
|| dev
->subsystem_vendor
== ss_vendor
) &&
287 (ss_device
== PCI_ANY_ID
|| dev
->subsystem_device
== ss_device
))
293 dev
= pci_dev_get(dev
);
294 up_read(&pci_bus_sem
);
300 * pci_get_device - begin or continue searching for a PCI device by vendor/device id
301 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
302 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
303 * @from: Previous PCI device found in search, or %NULL for new search.
305 * Iterates through the list of known PCI devices. If a PCI device is
306 * found with a matching @vendor and @device, the reference count to the
307 * device is incremented and a pointer to its device structure is returned.
308 * Otherwise, %NULL is returned. A new search is initiated by passing %NULL
309 * as the @from argument. Otherwise if @from is not %NULL, searches continue
310 * from next device on the global list. The reference count for @from is
311 * always decremented if it is not %NULL.
314 pci_get_device(unsigned int vendor
, unsigned int device
, struct pci_dev
*from
)
316 return pci_get_subsys(vendor
, device
, PCI_ANY_ID
, PCI_ANY_ID
, from
);
320 * pci_get_device_reverse - begin or continue searching for a PCI device by vendor/device id
321 * @vendor: PCI vendor id to match, or %PCI_ANY_ID to match all vendor ids
322 * @device: PCI device id to match, or %PCI_ANY_ID to match all device ids
323 * @from: Previous PCI device found in search, or %NULL for new search.
325 * Iterates through the list of known PCI devices in the reverse order of
327 * If a PCI device is found with a matching @vendor and @device, the reference
328 * count to the device is incremented and a pointer to its device structure
329 * is returned Otherwise, %NULL is returned. A new search is initiated by
330 * passing %NULL as the @from argument. Otherwise if @from is not %NULL,
331 * searches continue from next device on the global list. The reference
332 * count for @from is always decremented if it is not %NULL.
335 pci_get_device_reverse(unsigned int vendor
, unsigned int device
, struct pci_dev
*from
)
340 WARN_ON(in_interrupt());
341 down_read(&pci_bus_sem
);
342 n
= from
? from
->global_list
.prev
: pci_devices
.prev
;
344 while (n
&& (n
!= &pci_devices
)) {
346 if ((vendor
== PCI_ANY_ID
|| dev
->vendor
== vendor
) &&
347 (device
== PCI_ANY_ID
|| dev
->device
== device
))
353 dev
= pci_dev_get(dev
);
354 up_read(&pci_bus_sem
);
360 * pci_get_class - begin or continue searching for a PCI device by class
361 * @class: search for a PCI device with this class designation
362 * @from: Previous PCI device found in search, or %NULL for new search.
364 * Iterates through the list of known PCI devices. If a PCI device is
365 * found with a matching @class, the reference count to the device is
366 * incremented and a pointer to its device structure is returned.
367 * Otherwise, %NULL is returned.
368 * A new search is initiated by passing %NULL as the @from argument.
369 * Otherwise if @from is not %NULL, searches continue from next device
370 * on the global list. The reference count for @from is always decremented
371 * if it is not %NULL.
373 struct pci_dev
*pci_get_class(unsigned int class, struct pci_dev
*from
)
378 WARN_ON(in_interrupt());
379 down_read(&pci_bus_sem
);
380 n
= from
? from
->global_list
.next
: pci_devices
.next
;
382 while (n
&& (n
!= &pci_devices
)) {
384 if (dev
->class == class)
390 dev
= pci_dev_get(dev
);
391 up_read(&pci_bus_sem
);
396 const struct pci_device_id
*pci_find_present(const struct pci_device_id
*ids
)
399 const struct pci_device_id
*found
= NULL
;
401 WARN_ON(in_interrupt());
402 down_read(&pci_bus_sem
);
403 while (ids
->vendor
|| ids
->subvendor
|| ids
->class_mask
) {
404 list_for_each_entry(dev
, &pci_devices
, global_list
) {
405 if ((found
= pci_match_one_device(ids
, dev
)) != NULL
)
410 up_read(&pci_bus_sem
);
415 * pci_dev_present - Returns 1 if device matching the device list is present, 0 if not.
416 * @ids: A pointer to a null terminated list of struct pci_device_id structures
417 * that describe the type of PCI device the caller is trying to find.
419 * Obvious fact: You do not have a reference to any device that might be found
420 * by this function, so if that device is removed from the system right after
421 * this function is finished, the value will be stale. Use this function to
422 * find devices that are usually built into a system, or for a general hint as
423 * to if another device happens to be present at this specific moment in time.
425 int pci_dev_present(const struct pci_device_id
*ids
)
427 return pci_find_present(ids
) == NULL
? 0 : 1;
430 EXPORT_SYMBOL(pci_dev_present
);
431 EXPORT_SYMBOL(pci_find_present
);
433 EXPORT_SYMBOL(pci_find_device
);
434 EXPORT_SYMBOL(pci_find_slot
);
435 /* For boot time work */
436 EXPORT_SYMBOL(pci_find_bus
);
437 EXPORT_SYMBOL(pci_find_next_bus
);
439 EXPORT_SYMBOL(pci_get_device
);
440 EXPORT_SYMBOL(pci_get_device_reverse
);
441 EXPORT_SYMBOL(pci_get_subsys
);
442 EXPORT_SYMBOL(pci_get_slot
);
443 EXPORT_SYMBOL(pci_get_bus_and_slot
);
444 EXPORT_SYMBOL(pci_get_class
);