xref: /openbmc/linux/drivers/pci/pci-driver.c (revision 3821a065)
1 /*
2  * drivers/pci/pci-driver.c
3  *
4  * (C) Copyright 2002-2004, 2007 Greg Kroah-Hartman <greg@kroah.com>
5  * (C) Copyright 2007 Novell Inc.
6  *
7  * Released under the GPL v2 only.
8  *
9  */
10 
11 #include <linux/pci.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/device.h>
15 #include <linux/mempolicy.h>
16 #include <linux/string.h>
17 #include <linux/slab.h>
18 #include <linux/sched.h>
19 #include <linux/cpu.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/suspend.h>
22 #include <linux/kexec.h>
23 #include "pci.h"
24 
25 struct pci_dynid {
26 	struct list_head node;
27 	struct pci_device_id id;
28 };
29 
30 /**
31  * pci_add_dynid - add a new PCI device ID to this driver and re-probe devices
32  * @drv: target pci driver
33  * @vendor: PCI vendor ID
34  * @device: PCI device ID
35  * @subvendor: PCI subvendor ID
36  * @subdevice: PCI subdevice ID
37  * @class: PCI class
38  * @class_mask: PCI class mask
39  * @driver_data: private driver data
40  *
41  * Adds a new dynamic pci device ID to this driver and causes the
42  * driver to probe for all devices again.  @drv must have been
43  * registered prior to calling this function.
44  *
45  * CONTEXT:
46  * Does GFP_KERNEL allocation.
47  *
48  * RETURNS:
49  * 0 on success, -errno on failure.
50  */
51 int pci_add_dynid(struct pci_driver *drv,
52 		  unsigned int vendor, unsigned int device,
53 		  unsigned int subvendor, unsigned int subdevice,
54 		  unsigned int class, unsigned int class_mask,
55 		  unsigned long driver_data)
56 {
57 	struct pci_dynid *dynid;
58 
59 	dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
60 	if (!dynid)
61 		return -ENOMEM;
62 
63 	dynid->id.vendor = vendor;
64 	dynid->id.device = device;
65 	dynid->id.subvendor = subvendor;
66 	dynid->id.subdevice = subdevice;
67 	dynid->id.class = class;
68 	dynid->id.class_mask = class_mask;
69 	dynid->id.driver_data = driver_data;
70 
71 	spin_lock(&drv->dynids.lock);
72 	list_add_tail(&dynid->node, &drv->dynids.list);
73 	spin_unlock(&drv->dynids.lock);
74 
75 	return driver_attach(&drv->driver);
76 }
77 EXPORT_SYMBOL_GPL(pci_add_dynid);
78 
79 static void pci_free_dynids(struct pci_driver *drv)
80 {
81 	struct pci_dynid *dynid, *n;
82 
83 	spin_lock(&drv->dynids.lock);
84 	list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
85 		list_del(&dynid->node);
86 		kfree(dynid);
87 	}
88 	spin_unlock(&drv->dynids.lock);
89 }
90 
91 /**
92  * store_new_id - sysfs frontend to pci_add_dynid()
93  * @driver: target device driver
94  * @buf: buffer for scanning device ID data
95  * @count: input size
96  *
97  * Allow PCI IDs to be added to an existing driver via sysfs.
98  */
99 static ssize_t store_new_id(struct device_driver *driver, const char *buf,
100 			    size_t count)
101 {
102 	struct pci_driver *pdrv = to_pci_driver(driver);
103 	const struct pci_device_id *ids = pdrv->id_table;
104 	__u32 vendor, device, subvendor = PCI_ANY_ID,
105 		subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
106 	unsigned long driver_data = 0;
107 	int fields = 0;
108 	int retval = 0;
109 
110 	fields = sscanf(buf, "%x %x %x %x %x %x %lx",
111 			&vendor, &device, &subvendor, &subdevice,
112 			&class, &class_mask, &driver_data);
113 	if (fields < 2)
114 		return -EINVAL;
115 
116 	if (fields != 7) {
117 		struct pci_dev *pdev = kzalloc(sizeof(*pdev), GFP_KERNEL);
118 		if (!pdev)
119 			return -ENOMEM;
120 
121 		pdev->vendor = vendor;
122 		pdev->device = device;
123 		pdev->subsystem_vendor = subvendor;
124 		pdev->subsystem_device = subdevice;
125 		pdev->class = class;
126 
127 		if (pci_match_id(pdrv->id_table, pdev))
128 			retval = -EEXIST;
129 
130 		kfree(pdev);
131 
132 		if (retval)
133 			return retval;
134 	}
135 
136 	/* Only accept driver_data values that match an existing id_table
137 	   entry */
138 	if (ids) {
139 		retval = -EINVAL;
140 		while (ids->vendor || ids->subvendor || ids->class_mask) {
141 			if (driver_data == ids->driver_data) {
142 				retval = 0;
143 				break;
144 			}
145 			ids++;
146 		}
147 		if (retval)	/* No match */
148 			return retval;
149 	}
150 
151 	retval = pci_add_dynid(pdrv, vendor, device, subvendor, subdevice,
152 			       class, class_mask, driver_data);
153 	if (retval)
154 		return retval;
155 	return count;
156 }
157 static DRIVER_ATTR(new_id, S_IWUSR, NULL, store_new_id);
158 
159 /**
160  * store_remove_id - remove a PCI device ID from this driver
161  * @driver: target device driver
162  * @buf: buffer for scanning device ID data
163  * @count: input size
164  *
165  * Removes a dynamic pci device ID to this driver.
166  */
167 static ssize_t store_remove_id(struct device_driver *driver, const char *buf,
168 			       size_t count)
169 {
170 	struct pci_dynid *dynid, *n;
171 	struct pci_driver *pdrv = to_pci_driver(driver);
172 	__u32 vendor, device, subvendor = PCI_ANY_ID,
173 		subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
174 	int fields = 0;
175 	int retval = -ENODEV;
176 
177 	fields = sscanf(buf, "%x %x %x %x %x %x",
178 			&vendor, &device, &subvendor, &subdevice,
179 			&class, &class_mask);
180 	if (fields < 2)
181 		return -EINVAL;
182 
183 	spin_lock(&pdrv->dynids.lock);
184 	list_for_each_entry_safe(dynid, n, &pdrv->dynids.list, node) {
185 		struct pci_device_id *id = &dynid->id;
186 		if ((id->vendor == vendor) &&
187 		    (id->device == device) &&
188 		    (subvendor == PCI_ANY_ID || id->subvendor == subvendor) &&
189 		    (subdevice == PCI_ANY_ID || id->subdevice == subdevice) &&
190 		    !((id->class ^ class) & class_mask)) {
191 			list_del(&dynid->node);
192 			kfree(dynid);
193 			retval = 0;
194 			break;
195 		}
196 	}
197 	spin_unlock(&pdrv->dynids.lock);
198 
199 	if (retval)
200 		return retval;
201 	return count;
202 }
203 static DRIVER_ATTR(remove_id, S_IWUSR, NULL, store_remove_id);
204 
205 static struct attribute *pci_drv_attrs[] = {
206 	&driver_attr_new_id.attr,
207 	&driver_attr_remove_id.attr,
208 	NULL,
209 };
210 ATTRIBUTE_GROUPS(pci_drv);
211 
212 /**
213  * pci_match_id - See if a pci device matches a given pci_id table
214  * @ids: array of PCI device id structures to search in
215  * @dev: the PCI device structure to match against.
216  *
217  * Used by a driver to check whether a PCI device present in the
218  * system is in its list of supported devices.  Returns the matching
219  * pci_device_id structure or %NULL if there is no match.
220  *
221  * Deprecated, don't use this as it will not catch any dynamic ids
222  * that a driver might want to check for.
223  */
224 const struct pci_device_id *pci_match_id(const struct pci_device_id *ids,
225 					 struct pci_dev *dev)
226 {
227 	if (ids) {
228 		while (ids->vendor || ids->subvendor || ids->class_mask) {
229 			if (pci_match_one_device(ids, dev))
230 				return ids;
231 			ids++;
232 		}
233 	}
234 	return NULL;
235 }
236 EXPORT_SYMBOL(pci_match_id);
237 
238 static const struct pci_device_id pci_device_id_any = {
239 	.vendor = PCI_ANY_ID,
240 	.device = PCI_ANY_ID,
241 	.subvendor = PCI_ANY_ID,
242 	.subdevice = PCI_ANY_ID,
243 };
244 
245 /**
246  * pci_match_device - Tell if a PCI device structure has a matching PCI device id structure
247  * @drv: the PCI driver to match against
248  * @dev: the PCI device structure to match against
249  *
250  * Used by a driver to check whether a PCI device present in the
251  * system is in its list of supported devices.  Returns the matching
252  * pci_device_id structure or %NULL if there is no match.
253  */
254 static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
255 						    struct pci_dev *dev)
256 {
257 	struct pci_dynid *dynid;
258 	const struct pci_device_id *found_id = NULL;
259 
260 	/* When driver_override is set, only bind to the matching driver */
261 	if (dev->driver_override && strcmp(dev->driver_override, drv->name))
262 		return NULL;
263 
264 	/* Look at the dynamic ids first, before the static ones */
265 	spin_lock(&drv->dynids.lock);
266 	list_for_each_entry(dynid, &drv->dynids.list, node) {
267 		if (pci_match_one_device(&dynid->id, dev)) {
268 			found_id = &dynid->id;
269 			break;
270 		}
271 	}
272 	spin_unlock(&drv->dynids.lock);
273 
274 	if (!found_id)
275 		found_id = pci_match_id(drv->id_table, dev);
276 
277 	/* driver_override will always match, send a dummy id */
278 	if (!found_id && dev->driver_override)
279 		found_id = &pci_device_id_any;
280 
281 	return found_id;
282 }
283 
284 struct drv_dev_and_id {
285 	struct pci_driver *drv;
286 	struct pci_dev *dev;
287 	const struct pci_device_id *id;
288 };
289 
290 static long local_pci_probe(void *_ddi)
291 {
292 	struct drv_dev_and_id *ddi = _ddi;
293 	struct pci_dev *pci_dev = ddi->dev;
294 	struct pci_driver *pci_drv = ddi->drv;
295 	struct device *dev = &pci_dev->dev;
296 	int rc;
297 
298 	/*
299 	 * Unbound PCI devices are always put in D0, regardless of
300 	 * runtime PM status.  During probe, the device is set to
301 	 * active and the usage count is incremented.  If the driver
302 	 * supports runtime PM, it should call pm_runtime_put_noidle()
303 	 * in its probe routine and pm_runtime_get_noresume() in its
304 	 * remove routine.
305 	 */
306 	pm_runtime_get_sync(dev);
307 	pci_dev->driver = pci_drv;
308 	rc = pci_drv->probe(pci_dev, ddi->id);
309 	if (!rc)
310 		return rc;
311 	if (rc < 0) {
312 		pci_dev->driver = NULL;
313 		pm_runtime_put_sync(dev);
314 		return rc;
315 	}
316 	/*
317 	 * Probe function should return < 0 for failure, 0 for success
318 	 * Treat values > 0 as success, but warn.
319 	 */
320 	dev_warn(dev, "Driver probe function unexpectedly returned %d\n", rc);
321 	return 0;
322 }
323 
324 static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
325 			  const struct pci_device_id *id)
326 {
327 	int error, node;
328 	struct drv_dev_and_id ddi = { drv, dev, id };
329 
330 	/*
331 	 * Execute driver initialization on node where the device is
332 	 * attached.  This way the driver likely allocates its local memory
333 	 * on the right node.
334 	 */
335 	node = dev_to_node(&dev->dev);
336 
337 	/*
338 	 * On NUMA systems, we are likely to call a PF probe function using
339 	 * work_on_cpu().  If that probe calls pci_enable_sriov() (which
340 	 * adds the VF devices via pci_bus_add_device()), we may re-enter
341 	 * this function to call the VF probe function.  Calling
342 	 * work_on_cpu() again will cause a lockdep warning.  Since VFs are
343 	 * always on the same node as the PF, we can work around this by
344 	 * avoiding work_on_cpu() when we're already on the correct node.
345 	 *
346 	 * Preemption is enabled, so it's theoretically unsafe to use
347 	 * numa_node_id(), but even if we run the probe function on the
348 	 * wrong node, it should be functionally correct.
349 	 */
350 	if (node >= 0 && node != numa_node_id()) {
351 		int cpu;
352 
353 		get_online_cpus();
354 		cpu = cpumask_any_and(cpumask_of_node(node), cpu_online_mask);
355 		if (cpu < nr_cpu_ids)
356 			error = work_on_cpu(cpu, local_pci_probe, &ddi);
357 		else
358 			error = local_pci_probe(&ddi);
359 		put_online_cpus();
360 	} else
361 		error = local_pci_probe(&ddi);
362 
363 	return error;
364 }
365 
366 /**
367  * __pci_device_probe - check if a driver wants to claim a specific PCI device
368  * @drv: driver to call to check if it wants the PCI device
369  * @pci_dev: PCI device being probed
370  *
371  * returns 0 on success, else error.
372  * side-effect: pci_dev->driver is set to drv when drv claims pci_dev.
373  */
374 static int __pci_device_probe(struct pci_driver *drv, struct pci_dev *pci_dev)
375 {
376 	const struct pci_device_id *id;
377 	int error = 0;
378 
379 	if (!pci_dev->driver && drv->probe) {
380 		error = -ENODEV;
381 
382 		id = pci_match_device(drv, pci_dev);
383 		if (id)
384 			error = pci_call_probe(drv, pci_dev, id);
385 		if (error >= 0)
386 			error = 0;
387 	}
388 	return error;
389 }
390 
391 int __weak pcibios_alloc_irq(struct pci_dev *dev)
392 {
393 	return 0;
394 }
395 
396 void __weak pcibios_free_irq(struct pci_dev *dev)
397 {
398 }
399 
400 static int pci_device_probe(struct device *dev)
401 {
402 	int error;
403 	struct pci_dev *pci_dev = to_pci_dev(dev);
404 	struct pci_driver *drv = to_pci_driver(dev->driver);
405 
406 	error = pcibios_alloc_irq(pci_dev);
407 	if (error < 0)
408 		return error;
409 
410 	pci_dev_get(pci_dev);
411 	error = __pci_device_probe(drv, pci_dev);
412 	if (error) {
413 		pcibios_free_irq(pci_dev);
414 		pci_dev_put(pci_dev);
415 	}
416 
417 	return error;
418 }
419 
420 static int pci_device_remove(struct device *dev)
421 {
422 	struct pci_dev *pci_dev = to_pci_dev(dev);
423 	struct pci_driver *drv = pci_dev->driver;
424 
425 	if (drv) {
426 		if (drv->remove) {
427 			pm_runtime_get_sync(dev);
428 			drv->remove(pci_dev);
429 			pm_runtime_put_noidle(dev);
430 		}
431 		pcibios_free_irq(pci_dev);
432 		pci_dev->driver = NULL;
433 	}
434 
435 	/* Undo the runtime PM settings in local_pci_probe() */
436 	pm_runtime_put_sync(dev);
437 
438 	/*
439 	 * If the device is still on, set the power state as "unknown",
440 	 * since it might change by the next time we load the driver.
441 	 */
442 	if (pci_dev->current_state == PCI_D0)
443 		pci_dev->current_state = PCI_UNKNOWN;
444 
445 	/*
446 	 * We would love to complain here if pci_dev->is_enabled is set, that
447 	 * the driver should have called pci_disable_device(), but the
448 	 * unfortunate fact is there are too many odd BIOS and bridge setups
449 	 * that don't like drivers doing that all of the time.
450 	 * Oh well, we can dream of sane hardware when we sleep, no matter how
451 	 * horrible the crap we have to deal with is when we are awake...
452 	 */
453 
454 	pci_dev_put(pci_dev);
455 	return 0;
456 }
457 
458 static void pci_device_shutdown(struct device *dev)
459 {
460 	struct pci_dev *pci_dev = to_pci_dev(dev);
461 	struct pci_driver *drv = pci_dev->driver;
462 
463 	pm_runtime_resume(dev);
464 
465 	if (drv && drv->shutdown)
466 		drv->shutdown(pci_dev);
467 	pci_msi_shutdown(pci_dev);
468 	pci_msix_shutdown(pci_dev);
469 
470 #ifdef CONFIG_KEXEC_CORE
471 	/*
472 	 * If this is a kexec reboot, turn off Bus Master bit on the
473 	 * device to tell it to not continue to do DMA. Don't touch
474 	 * devices in D3cold or unknown states.
475 	 * If it is not a kexec reboot, firmware will hit the PCI
476 	 * devices with big hammer and stop their DMA any way.
477 	 */
478 	if (kexec_in_progress && (pci_dev->current_state <= PCI_D3hot))
479 		pci_clear_master(pci_dev);
480 #endif
481 }
482 
483 #ifdef CONFIG_PM
484 
485 /* Auxiliary functions used for system resume and run-time resume. */
486 
487 /**
488  * pci_restore_standard_config - restore standard config registers of PCI device
489  * @pci_dev: PCI device to handle
490  */
491 static int pci_restore_standard_config(struct pci_dev *pci_dev)
492 {
493 	pci_update_current_state(pci_dev, PCI_UNKNOWN);
494 
495 	if (pci_dev->current_state != PCI_D0) {
496 		int error = pci_set_power_state(pci_dev, PCI_D0);
497 		if (error)
498 			return error;
499 	}
500 
501 	pci_restore_state(pci_dev);
502 	return 0;
503 }
504 
505 #endif
506 
507 #ifdef CONFIG_PM_SLEEP
508 
509 static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
510 {
511 	pci_power_up(pci_dev);
512 	pci_restore_state(pci_dev);
513 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
514 }
515 
516 /*
517  * Default "suspend" method for devices that have no driver provided suspend,
518  * or not even a driver at all (second part).
519  */
520 static void pci_pm_set_unknown_state(struct pci_dev *pci_dev)
521 {
522 	/*
523 	 * mark its power state as "unknown", since we don't know if
524 	 * e.g. the BIOS will change its device state when we suspend.
525 	 */
526 	if (pci_dev->current_state == PCI_D0)
527 		pci_dev->current_state = PCI_UNKNOWN;
528 }
529 
530 /*
531  * Default "resume" method for devices that have no driver provided resume,
532  * or not even a driver at all (second part).
533  */
534 static int pci_pm_reenable_device(struct pci_dev *pci_dev)
535 {
536 	int retval;
537 
538 	/* if the device was enabled before suspend, reenable */
539 	retval = pci_reenable_device(pci_dev);
540 	/*
541 	 * if the device was busmaster before the suspend, make it busmaster
542 	 * again
543 	 */
544 	if (pci_dev->is_busmaster)
545 		pci_set_master(pci_dev);
546 
547 	return retval;
548 }
549 
550 static int pci_legacy_suspend(struct device *dev, pm_message_t state)
551 {
552 	struct pci_dev *pci_dev = to_pci_dev(dev);
553 	struct pci_driver *drv = pci_dev->driver;
554 
555 	if (drv && drv->suspend) {
556 		pci_power_t prev = pci_dev->current_state;
557 		int error;
558 
559 		error = drv->suspend(pci_dev, state);
560 		suspend_report_result(drv->suspend, error);
561 		if (error)
562 			return error;
563 
564 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
565 		    && pci_dev->current_state != PCI_UNKNOWN) {
566 			WARN_ONCE(pci_dev->current_state != prev,
567 				"PCI PM: Device state not saved by %pF\n",
568 				drv->suspend);
569 		}
570 	}
571 
572 	pci_fixup_device(pci_fixup_suspend, pci_dev);
573 
574 	return 0;
575 }
576 
577 static int pci_legacy_suspend_late(struct device *dev, pm_message_t state)
578 {
579 	struct pci_dev *pci_dev = to_pci_dev(dev);
580 	struct pci_driver *drv = pci_dev->driver;
581 
582 	if (drv && drv->suspend_late) {
583 		pci_power_t prev = pci_dev->current_state;
584 		int error;
585 
586 		error = drv->suspend_late(pci_dev, state);
587 		suspend_report_result(drv->suspend_late, error);
588 		if (error)
589 			return error;
590 
591 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
592 		    && pci_dev->current_state != PCI_UNKNOWN) {
593 			WARN_ONCE(pci_dev->current_state != prev,
594 				"PCI PM: Device state not saved by %pF\n",
595 				drv->suspend_late);
596 			goto Fixup;
597 		}
598 	}
599 
600 	if (!pci_dev->state_saved)
601 		pci_save_state(pci_dev);
602 
603 	pci_pm_set_unknown_state(pci_dev);
604 
605 Fixup:
606 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
607 
608 	return 0;
609 }
610 
611 static int pci_legacy_resume_early(struct device *dev)
612 {
613 	struct pci_dev *pci_dev = to_pci_dev(dev);
614 	struct pci_driver *drv = pci_dev->driver;
615 
616 	return drv && drv->resume_early ?
617 			drv->resume_early(pci_dev) : 0;
618 }
619 
620 static int pci_legacy_resume(struct device *dev)
621 {
622 	struct pci_dev *pci_dev = to_pci_dev(dev);
623 	struct pci_driver *drv = pci_dev->driver;
624 
625 	pci_fixup_device(pci_fixup_resume, pci_dev);
626 
627 	return drv && drv->resume ?
628 			drv->resume(pci_dev) : pci_pm_reenable_device(pci_dev);
629 }
630 
631 /* Auxiliary functions used by the new power management framework */
632 
633 static void pci_pm_default_resume(struct pci_dev *pci_dev)
634 {
635 	pci_fixup_device(pci_fixup_resume, pci_dev);
636 
637 	if (!pci_has_subordinate(pci_dev))
638 		pci_enable_wake(pci_dev, PCI_D0, false);
639 }
640 
641 static void pci_pm_default_suspend(struct pci_dev *pci_dev)
642 {
643 	/* Disable non-bridge devices without PM support */
644 	if (!pci_has_subordinate(pci_dev))
645 		pci_disable_enabled_device(pci_dev);
646 }
647 
648 static bool pci_has_legacy_pm_support(struct pci_dev *pci_dev)
649 {
650 	struct pci_driver *drv = pci_dev->driver;
651 	bool ret = drv && (drv->suspend || drv->suspend_late || drv->resume
652 		|| drv->resume_early);
653 
654 	/*
655 	 * Legacy PM support is used by default, so warn if the new framework is
656 	 * supported as well.  Drivers are supposed to support either the
657 	 * former, or the latter, but not both at the same time.
658 	 */
659 	WARN(ret && drv->driver.pm, "driver %s device %04x:%04x\n",
660 		drv->name, pci_dev->vendor, pci_dev->device);
661 
662 	return ret;
663 }
664 
665 /* New power management framework */
666 
667 static int pci_pm_prepare(struct device *dev)
668 {
669 	struct device_driver *drv = dev->driver;
670 
671 	/*
672 	 * Devices having power.ignore_children set may still be necessary for
673 	 * suspending their children in the next phase of device suspend.
674 	 */
675 	if (dev->power.ignore_children)
676 		pm_runtime_resume(dev);
677 
678 	if (drv && drv->pm && drv->pm->prepare) {
679 		int error = drv->pm->prepare(dev);
680 		if (error)
681 			return error;
682 	}
683 	return pci_dev_keep_suspended(to_pci_dev(dev));
684 }
685 
686 
687 #else /* !CONFIG_PM_SLEEP */
688 
689 #define pci_pm_prepare	NULL
690 
691 #endif /* !CONFIG_PM_SLEEP */
692 
693 #ifdef CONFIG_SUSPEND
694 
695 static int pci_pm_suspend(struct device *dev)
696 {
697 	struct pci_dev *pci_dev = to_pci_dev(dev);
698 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
699 
700 	if (pci_has_legacy_pm_support(pci_dev))
701 		return pci_legacy_suspend(dev, PMSG_SUSPEND);
702 
703 	if (!pm) {
704 		pci_pm_default_suspend(pci_dev);
705 		goto Fixup;
706 	}
707 
708 	/*
709 	 * PCI devices suspended at run time need to be resumed at this point,
710 	 * because in general it is necessary to reconfigure them for system
711 	 * suspend.  Namely, if the device is supposed to wake up the system
712 	 * from the sleep state, we may need to reconfigure it for this purpose.
713 	 * In turn, if the device is not supposed to wake up the system from the
714 	 * sleep state, we'll have to prevent it from signaling wake-up.
715 	 */
716 	pm_runtime_resume(dev);
717 
718 	pci_dev->state_saved = false;
719 	if (pm->suspend) {
720 		pci_power_t prev = pci_dev->current_state;
721 		int error;
722 
723 		error = pm->suspend(dev);
724 		suspend_report_result(pm->suspend, error);
725 		if (error)
726 			return error;
727 
728 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
729 		    && pci_dev->current_state != PCI_UNKNOWN) {
730 			WARN_ONCE(pci_dev->current_state != prev,
731 				"PCI PM: State of device not saved by %pF\n",
732 				pm->suspend);
733 		}
734 	}
735 
736  Fixup:
737 	pci_fixup_device(pci_fixup_suspend, pci_dev);
738 
739 	return 0;
740 }
741 
742 static int pci_pm_suspend_noirq(struct device *dev)
743 {
744 	struct pci_dev *pci_dev = to_pci_dev(dev);
745 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
746 
747 	if (pci_has_legacy_pm_support(pci_dev))
748 		return pci_legacy_suspend_late(dev, PMSG_SUSPEND);
749 
750 	if (!pm) {
751 		pci_save_state(pci_dev);
752 		goto Fixup;
753 	}
754 
755 	if (pm->suspend_noirq) {
756 		pci_power_t prev = pci_dev->current_state;
757 		int error;
758 
759 		error = pm->suspend_noirq(dev);
760 		suspend_report_result(pm->suspend_noirq, error);
761 		if (error)
762 			return error;
763 
764 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
765 		    && pci_dev->current_state != PCI_UNKNOWN) {
766 			WARN_ONCE(pci_dev->current_state != prev,
767 				"PCI PM: State of device not saved by %pF\n",
768 				pm->suspend_noirq);
769 			goto Fixup;
770 		}
771 	}
772 
773 	if (!pci_dev->state_saved) {
774 		pci_save_state(pci_dev);
775 		if (!pci_has_subordinate(pci_dev))
776 			pci_prepare_to_sleep(pci_dev);
777 	}
778 
779 	pci_pm_set_unknown_state(pci_dev);
780 
781 	/*
782 	 * Some BIOSes from ASUS have a bug: If a USB EHCI host controller's
783 	 * PCI COMMAND register isn't 0, the BIOS assumes that the controller
784 	 * hasn't been quiesced and tries to turn it off.  If the controller
785 	 * is already in D3, this can hang or cause memory corruption.
786 	 *
787 	 * Since the value of the COMMAND register doesn't matter once the
788 	 * device has been suspended, we can safely set it to 0 here.
789 	 */
790 	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
791 		pci_write_config_word(pci_dev, PCI_COMMAND, 0);
792 
793 Fixup:
794 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
795 
796 	return 0;
797 }
798 
799 static int pci_pm_resume_noirq(struct device *dev)
800 {
801 	struct pci_dev *pci_dev = to_pci_dev(dev);
802 	struct device_driver *drv = dev->driver;
803 	int error = 0;
804 
805 	pci_pm_default_resume_early(pci_dev);
806 
807 	if (pci_has_legacy_pm_support(pci_dev))
808 		return pci_legacy_resume_early(dev);
809 
810 	if (drv && drv->pm && drv->pm->resume_noirq)
811 		error = drv->pm->resume_noirq(dev);
812 
813 	return error;
814 }
815 
816 static int pci_pm_resume(struct device *dev)
817 {
818 	struct pci_dev *pci_dev = to_pci_dev(dev);
819 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
820 	int error = 0;
821 
822 	/*
823 	 * This is necessary for the suspend error path in which resume is
824 	 * called without restoring the standard config registers of the device.
825 	 */
826 	if (pci_dev->state_saved)
827 		pci_restore_standard_config(pci_dev);
828 
829 	if (pci_has_legacy_pm_support(pci_dev))
830 		return pci_legacy_resume(dev);
831 
832 	pci_pm_default_resume(pci_dev);
833 
834 	if (pm) {
835 		if (pm->resume)
836 			error = pm->resume(dev);
837 	} else {
838 		pci_pm_reenable_device(pci_dev);
839 	}
840 
841 	return error;
842 }
843 
844 #else /* !CONFIG_SUSPEND */
845 
846 #define pci_pm_suspend		NULL
847 #define pci_pm_suspend_noirq	NULL
848 #define pci_pm_resume		NULL
849 #define pci_pm_resume_noirq	NULL
850 
851 #endif /* !CONFIG_SUSPEND */
852 
853 #ifdef CONFIG_HIBERNATE_CALLBACKS
854 
855 
856 /*
857  * pcibios_pm_ops - provide arch-specific hooks when a PCI device is doing
858  * a hibernate transition
859  */
860 struct dev_pm_ops __weak pcibios_pm_ops;
861 
862 static int pci_pm_freeze(struct device *dev)
863 {
864 	struct pci_dev *pci_dev = to_pci_dev(dev);
865 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
866 
867 	if (pci_has_legacy_pm_support(pci_dev))
868 		return pci_legacy_suspend(dev, PMSG_FREEZE);
869 
870 	if (!pm) {
871 		pci_pm_default_suspend(pci_dev);
872 		return 0;
873 	}
874 
875 	/*
876 	 * This used to be done in pci_pm_prepare() for all devices and some
877 	 * drivers may depend on it, so do it here.  Ideally, runtime-suspended
878 	 * devices should not be touched during freeze/thaw transitions,
879 	 * however.
880 	 */
881 	pm_runtime_resume(dev);
882 
883 	pci_dev->state_saved = false;
884 	if (pm->freeze) {
885 		int error;
886 
887 		error = pm->freeze(dev);
888 		suspend_report_result(pm->freeze, error);
889 		if (error)
890 			return error;
891 	}
892 
893 	if (pcibios_pm_ops.freeze)
894 		return pcibios_pm_ops.freeze(dev);
895 
896 	return 0;
897 }
898 
899 static int pci_pm_freeze_noirq(struct device *dev)
900 {
901 	struct pci_dev *pci_dev = to_pci_dev(dev);
902 	struct device_driver *drv = dev->driver;
903 
904 	if (pci_has_legacy_pm_support(pci_dev))
905 		return pci_legacy_suspend_late(dev, PMSG_FREEZE);
906 
907 	if (drv && drv->pm && drv->pm->freeze_noirq) {
908 		int error;
909 
910 		error = drv->pm->freeze_noirq(dev);
911 		suspend_report_result(drv->pm->freeze_noirq, error);
912 		if (error)
913 			return error;
914 	}
915 
916 	if (!pci_dev->state_saved)
917 		pci_save_state(pci_dev);
918 
919 	pci_pm_set_unknown_state(pci_dev);
920 
921 	if (pcibios_pm_ops.freeze_noirq)
922 		return pcibios_pm_ops.freeze_noirq(dev);
923 
924 	return 0;
925 }
926 
927 static int pci_pm_thaw_noirq(struct device *dev)
928 {
929 	struct pci_dev *pci_dev = to_pci_dev(dev);
930 	struct device_driver *drv = dev->driver;
931 	int error = 0;
932 
933 	if (pcibios_pm_ops.thaw_noirq) {
934 		error = pcibios_pm_ops.thaw_noirq(dev);
935 		if (error)
936 			return error;
937 	}
938 
939 	if (pci_has_legacy_pm_support(pci_dev))
940 		return pci_legacy_resume_early(dev);
941 
942 	pci_update_current_state(pci_dev, PCI_D0);
943 
944 	if (drv && drv->pm && drv->pm->thaw_noirq)
945 		error = drv->pm->thaw_noirq(dev);
946 
947 	return error;
948 }
949 
950 static int pci_pm_thaw(struct device *dev)
951 {
952 	struct pci_dev *pci_dev = to_pci_dev(dev);
953 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
954 	int error = 0;
955 
956 	if (pcibios_pm_ops.thaw) {
957 		error = pcibios_pm_ops.thaw(dev);
958 		if (error)
959 			return error;
960 	}
961 
962 	if (pci_has_legacy_pm_support(pci_dev))
963 		return pci_legacy_resume(dev);
964 
965 	if (pm) {
966 		if (pm->thaw)
967 			error = pm->thaw(dev);
968 	} else {
969 		pci_pm_reenable_device(pci_dev);
970 	}
971 
972 	pci_dev->state_saved = false;
973 
974 	return error;
975 }
976 
977 static int pci_pm_poweroff(struct device *dev)
978 {
979 	struct pci_dev *pci_dev = to_pci_dev(dev);
980 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
981 
982 	if (pci_has_legacy_pm_support(pci_dev))
983 		return pci_legacy_suspend(dev, PMSG_HIBERNATE);
984 
985 	if (!pm) {
986 		pci_pm_default_suspend(pci_dev);
987 		goto Fixup;
988 	}
989 
990 	/* The reason to do that is the same as in pci_pm_suspend(). */
991 	pm_runtime_resume(dev);
992 
993 	pci_dev->state_saved = false;
994 	if (pm->poweroff) {
995 		int error;
996 
997 		error = pm->poweroff(dev);
998 		suspend_report_result(pm->poweroff, error);
999 		if (error)
1000 			return error;
1001 	}
1002 
1003  Fixup:
1004 	pci_fixup_device(pci_fixup_suspend, pci_dev);
1005 
1006 	if (pcibios_pm_ops.poweroff)
1007 		return pcibios_pm_ops.poweroff(dev);
1008 
1009 	return 0;
1010 }
1011 
1012 static int pci_pm_poweroff_noirq(struct device *dev)
1013 {
1014 	struct pci_dev *pci_dev = to_pci_dev(dev);
1015 	struct device_driver *drv = dev->driver;
1016 
1017 	if (pci_has_legacy_pm_support(to_pci_dev(dev)))
1018 		return pci_legacy_suspend_late(dev, PMSG_HIBERNATE);
1019 
1020 	if (!drv || !drv->pm) {
1021 		pci_fixup_device(pci_fixup_suspend_late, pci_dev);
1022 		return 0;
1023 	}
1024 
1025 	if (drv->pm->poweroff_noirq) {
1026 		int error;
1027 
1028 		error = drv->pm->poweroff_noirq(dev);
1029 		suspend_report_result(drv->pm->poweroff_noirq, error);
1030 		if (error)
1031 			return error;
1032 	}
1033 
1034 	if (!pci_dev->state_saved && !pci_has_subordinate(pci_dev))
1035 		pci_prepare_to_sleep(pci_dev);
1036 
1037 	/*
1038 	 * The reason for doing this here is the same as for the analogous code
1039 	 * in pci_pm_suspend_noirq().
1040 	 */
1041 	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
1042 		pci_write_config_word(pci_dev, PCI_COMMAND, 0);
1043 
1044 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
1045 
1046 	if (pcibios_pm_ops.poweroff_noirq)
1047 		return pcibios_pm_ops.poweroff_noirq(dev);
1048 
1049 	return 0;
1050 }
1051 
1052 static int pci_pm_restore_noirq(struct device *dev)
1053 {
1054 	struct pci_dev *pci_dev = to_pci_dev(dev);
1055 	struct device_driver *drv = dev->driver;
1056 	int error = 0;
1057 
1058 	if (pcibios_pm_ops.restore_noirq) {
1059 		error = pcibios_pm_ops.restore_noirq(dev);
1060 		if (error)
1061 			return error;
1062 	}
1063 
1064 	pci_pm_default_resume_early(pci_dev);
1065 
1066 	if (pci_has_legacy_pm_support(pci_dev))
1067 		return pci_legacy_resume_early(dev);
1068 
1069 	if (drv && drv->pm && drv->pm->restore_noirq)
1070 		error = drv->pm->restore_noirq(dev);
1071 
1072 	return error;
1073 }
1074 
1075 static int pci_pm_restore(struct device *dev)
1076 {
1077 	struct pci_dev *pci_dev = to_pci_dev(dev);
1078 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1079 	int error = 0;
1080 
1081 	if (pcibios_pm_ops.restore) {
1082 		error = pcibios_pm_ops.restore(dev);
1083 		if (error)
1084 			return error;
1085 	}
1086 
1087 	/*
1088 	 * This is necessary for the hibernation error path in which restore is
1089 	 * called without restoring the standard config registers of the device.
1090 	 */
1091 	if (pci_dev->state_saved)
1092 		pci_restore_standard_config(pci_dev);
1093 
1094 	if (pci_has_legacy_pm_support(pci_dev))
1095 		return pci_legacy_resume(dev);
1096 
1097 	pci_pm_default_resume(pci_dev);
1098 
1099 	if (pm) {
1100 		if (pm->restore)
1101 			error = pm->restore(dev);
1102 	} else {
1103 		pci_pm_reenable_device(pci_dev);
1104 	}
1105 
1106 	return error;
1107 }
1108 
1109 #else /* !CONFIG_HIBERNATE_CALLBACKS */
1110 
1111 #define pci_pm_freeze		NULL
1112 #define pci_pm_freeze_noirq	NULL
1113 #define pci_pm_thaw		NULL
1114 #define pci_pm_thaw_noirq	NULL
1115 #define pci_pm_poweroff		NULL
1116 #define pci_pm_poweroff_noirq	NULL
1117 #define pci_pm_restore		NULL
1118 #define pci_pm_restore_noirq	NULL
1119 
1120 #endif /* !CONFIG_HIBERNATE_CALLBACKS */
1121 
1122 #ifdef CONFIG_PM
1123 
1124 static int pci_pm_runtime_suspend(struct device *dev)
1125 {
1126 	struct pci_dev *pci_dev = to_pci_dev(dev);
1127 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1128 	pci_power_t prev = pci_dev->current_state;
1129 	int error;
1130 
1131 	/*
1132 	 * If pci_dev->driver is not set (unbound), the device should
1133 	 * always remain in D0 regardless of the runtime PM status
1134 	 */
1135 	if (!pci_dev->driver)
1136 		return 0;
1137 
1138 	if (!pm || !pm->runtime_suspend)
1139 		return -ENOSYS;
1140 
1141 	pci_dev->state_saved = false;
1142 	pci_dev->no_d3cold = false;
1143 	error = pm->runtime_suspend(dev);
1144 	suspend_report_result(pm->runtime_suspend, error);
1145 	if (error)
1146 		return error;
1147 	if (!pci_dev->d3cold_allowed)
1148 		pci_dev->no_d3cold = true;
1149 
1150 	pci_fixup_device(pci_fixup_suspend, pci_dev);
1151 
1152 	if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
1153 	    && pci_dev->current_state != PCI_UNKNOWN) {
1154 		WARN_ONCE(pci_dev->current_state != prev,
1155 			"PCI PM: State of device not saved by %pF\n",
1156 			pm->runtime_suspend);
1157 		return 0;
1158 	}
1159 
1160 	if (!pci_dev->state_saved) {
1161 		pci_save_state(pci_dev);
1162 		pci_finish_runtime_suspend(pci_dev);
1163 	}
1164 
1165 	return 0;
1166 }
1167 
1168 static int pci_pm_runtime_resume(struct device *dev)
1169 {
1170 	int rc;
1171 	struct pci_dev *pci_dev = to_pci_dev(dev);
1172 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1173 
1174 	/*
1175 	 * If pci_dev->driver is not set (unbound), the device should
1176 	 * always remain in D0 regardless of the runtime PM status
1177 	 */
1178 	if (!pci_dev->driver)
1179 		return 0;
1180 
1181 	if (!pm || !pm->runtime_resume)
1182 		return -ENOSYS;
1183 
1184 	pci_restore_standard_config(pci_dev);
1185 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
1186 	__pci_enable_wake(pci_dev, PCI_D0, true, false);
1187 	pci_fixup_device(pci_fixup_resume, pci_dev);
1188 
1189 	rc = pm->runtime_resume(dev);
1190 
1191 	pci_dev->runtime_d3cold = false;
1192 
1193 	return rc;
1194 }
1195 
1196 static int pci_pm_runtime_idle(struct device *dev)
1197 {
1198 	struct pci_dev *pci_dev = to_pci_dev(dev);
1199 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1200 	int ret = 0;
1201 
1202 	/*
1203 	 * If pci_dev->driver is not set (unbound), the device should
1204 	 * always remain in D0 regardless of the runtime PM status
1205 	 */
1206 	if (!pci_dev->driver)
1207 		return 0;
1208 
1209 	if (!pm)
1210 		return -ENOSYS;
1211 
1212 	if (pm->runtime_idle)
1213 		ret = pm->runtime_idle(dev);
1214 
1215 	return ret;
1216 }
1217 
1218 static const struct dev_pm_ops pci_dev_pm_ops = {
1219 	.prepare = pci_pm_prepare,
1220 	.suspend = pci_pm_suspend,
1221 	.resume = pci_pm_resume,
1222 	.freeze = pci_pm_freeze,
1223 	.thaw = pci_pm_thaw,
1224 	.poweroff = pci_pm_poweroff,
1225 	.restore = pci_pm_restore,
1226 	.suspend_noirq = pci_pm_suspend_noirq,
1227 	.resume_noirq = pci_pm_resume_noirq,
1228 	.freeze_noirq = pci_pm_freeze_noirq,
1229 	.thaw_noirq = pci_pm_thaw_noirq,
1230 	.poweroff_noirq = pci_pm_poweroff_noirq,
1231 	.restore_noirq = pci_pm_restore_noirq,
1232 	.runtime_suspend = pci_pm_runtime_suspend,
1233 	.runtime_resume = pci_pm_runtime_resume,
1234 	.runtime_idle = pci_pm_runtime_idle,
1235 };
1236 
1237 #define PCI_PM_OPS_PTR	(&pci_dev_pm_ops)
1238 
1239 #else /* !CONFIG_PM */
1240 
1241 #define pci_pm_runtime_suspend	NULL
1242 #define pci_pm_runtime_resume	NULL
1243 #define pci_pm_runtime_idle	NULL
1244 
1245 #define PCI_PM_OPS_PTR	NULL
1246 
1247 #endif /* !CONFIG_PM */
1248 
1249 /**
1250  * __pci_register_driver - register a new pci driver
1251  * @drv: the driver structure to register
1252  * @owner: owner module of drv
1253  * @mod_name: module name string
1254  *
1255  * Adds the driver structure to the list of registered drivers.
1256  * Returns a negative value on error, otherwise 0.
1257  * If no error occurred, the driver remains registered even if
1258  * no device was claimed during registration.
1259  */
1260 int __pci_register_driver(struct pci_driver *drv, struct module *owner,
1261 			  const char *mod_name)
1262 {
1263 	/* initialize common driver fields */
1264 	drv->driver.name = drv->name;
1265 	drv->driver.bus = &pci_bus_type;
1266 	drv->driver.owner = owner;
1267 	drv->driver.mod_name = mod_name;
1268 
1269 	spin_lock_init(&drv->dynids.lock);
1270 	INIT_LIST_HEAD(&drv->dynids.list);
1271 
1272 	/* register with core */
1273 	return driver_register(&drv->driver);
1274 }
1275 EXPORT_SYMBOL(__pci_register_driver);
1276 
1277 /**
1278  * pci_unregister_driver - unregister a pci driver
1279  * @drv: the driver structure to unregister
1280  *
1281  * Deletes the driver structure from the list of registered PCI drivers,
1282  * gives it a chance to clean up by calling its remove() function for
1283  * each device it was responsible for, and marks those devices as
1284  * driverless.
1285  */
1286 
1287 void pci_unregister_driver(struct pci_driver *drv)
1288 {
1289 	driver_unregister(&drv->driver);
1290 	pci_free_dynids(drv);
1291 }
1292 EXPORT_SYMBOL(pci_unregister_driver);
1293 
1294 static struct pci_driver pci_compat_driver = {
1295 	.name = "compat"
1296 };
1297 
1298 /**
1299  * pci_dev_driver - get the pci_driver of a device
1300  * @dev: the device to query
1301  *
1302  * Returns the appropriate pci_driver structure or %NULL if there is no
1303  * registered driver for the device.
1304  */
1305 struct pci_driver *pci_dev_driver(const struct pci_dev *dev)
1306 {
1307 	if (dev->driver)
1308 		return dev->driver;
1309 	else {
1310 		int i;
1311 		for (i = 0; i <= PCI_ROM_RESOURCE; i++)
1312 			if (dev->resource[i].flags & IORESOURCE_BUSY)
1313 				return &pci_compat_driver;
1314 	}
1315 	return NULL;
1316 }
1317 EXPORT_SYMBOL(pci_dev_driver);
1318 
1319 /**
1320  * pci_bus_match - Tell if a PCI device structure has a matching PCI device id structure
1321  * @dev: the PCI device structure to match against
1322  * @drv: the device driver to search for matching PCI device id structures
1323  *
1324  * Used by a driver to check whether a PCI device present in the
1325  * system is in its list of supported devices. Returns the matching
1326  * pci_device_id structure or %NULL if there is no match.
1327  */
1328 static int pci_bus_match(struct device *dev, struct device_driver *drv)
1329 {
1330 	struct pci_dev *pci_dev = to_pci_dev(dev);
1331 	struct pci_driver *pci_drv;
1332 	const struct pci_device_id *found_id;
1333 
1334 	if (!pci_dev->match_driver)
1335 		return 0;
1336 
1337 	pci_drv = to_pci_driver(drv);
1338 	found_id = pci_match_device(pci_drv, pci_dev);
1339 	if (found_id)
1340 		return 1;
1341 
1342 	return 0;
1343 }
1344 
1345 /**
1346  * pci_dev_get - increments the reference count of the pci device structure
1347  * @dev: the device being referenced
1348  *
1349  * Each live reference to a device should be refcounted.
1350  *
1351  * Drivers for PCI devices should normally record such references in
1352  * their probe() methods, when they bind to a device, and release
1353  * them by calling pci_dev_put(), in their disconnect() methods.
1354  *
1355  * A pointer to the device with the incremented reference counter is returned.
1356  */
1357 struct pci_dev *pci_dev_get(struct pci_dev *dev)
1358 {
1359 	if (dev)
1360 		get_device(&dev->dev);
1361 	return dev;
1362 }
1363 EXPORT_SYMBOL(pci_dev_get);
1364 
1365 /**
1366  * pci_dev_put - release a use of the pci device structure
1367  * @dev: device that's been disconnected
1368  *
1369  * Must be called when a user of a device is finished with it.  When the last
1370  * user of the device calls this function, the memory of the device is freed.
1371  */
1372 void pci_dev_put(struct pci_dev *dev)
1373 {
1374 	if (dev)
1375 		put_device(&dev->dev);
1376 }
1377 EXPORT_SYMBOL(pci_dev_put);
1378 
1379 static int pci_uevent(struct device *dev, struct kobj_uevent_env *env)
1380 {
1381 	struct pci_dev *pdev;
1382 
1383 	if (!dev)
1384 		return -ENODEV;
1385 
1386 	pdev = to_pci_dev(dev);
1387 
1388 	if (add_uevent_var(env, "PCI_CLASS=%04X", pdev->class))
1389 		return -ENOMEM;
1390 
1391 	if (add_uevent_var(env, "PCI_ID=%04X:%04X", pdev->vendor, pdev->device))
1392 		return -ENOMEM;
1393 
1394 	if (add_uevent_var(env, "PCI_SUBSYS_ID=%04X:%04X", pdev->subsystem_vendor,
1395 			   pdev->subsystem_device))
1396 		return -ENOMEM;
1397 
1398 	if (add_uevent_var(env, "PCI_SLOT_NAME=%s", pci_name(pdev)))
1399 		return -ENOMEM;
1400 
1401 	if (add_uevent_var(env, "MODALIAS=pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02X",
1402 			   pdev->vendor, pdev->device,
1403 			   pdev->subsystem_vendor, pdev->subsystem_device,
1404 			   (u8)(pdev->class >> 16), (u8)(pdev->class >> 8),
1405 			   (u8)(pdev->class)))
1406 		return -ENOMEM;
1407 
1408 	return 0;
1409 }
1410 
1411 struct bus_type pci_bus_type = {
1412 	.name		= "pci",
1413 	.match		= pci_bus_match,
1414 	.uevent		= pci_uevent,
1415 	.probe		= pci_device_probe,
1416 	.remove		= pci_device_remove,
1417 	.shutdown	= pci_device_shutdown,
1418 	.dev_groups	= pci_dev_groups,
1419 	.bus_groups	= pci_bus_groups,
1420 	.drv_groups	= pci_drv_groups,
1421 	.pm		= PCI_PM_OPS_PTR,
1422 };
1423 EXPORT_SYMBOL(pci_bus_type);
1424 
1425 static int __init pci_driver_init(void)
1426 {
1427 	return bus_register(&pci_bus_type);
1428 }
1429 postcore_initcall(pci_driver_init);
1430