• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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  */
pci_add_dynid(struct pci_driver * drv,unsigned int vendor,unsigned int device,unsigned int subvendor,unsigned int subdevice,unsigned int class,unsigned int class_mask,unsigned long driver_data)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 
pci_free_dynids(struct pci_driver * drv)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  */
store_new_id(struct device_driver * driver,const char * buf,size_t count)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  */
store_remove_id(struct device_driver * driver,const char * buf,size_t count)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 	size_t 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 = count;
194 			break;
195 		}
196 	}
197 	spin_unlock(&pdrv->dynids.lock);
198 
199 	return retval;
200 }
201 static DRIVER_ATTR(remove_id, S_IWUSR, NULL, store_remove_id);
202 
203 static struct attribute *pci_drv_attrs[] = {
204 	&driver_attr_new_id.attr,
205 	&driver_attr_remove_id.attr,
206 	NULL,
207 };
208 ATTRIBUTE_GROUPS(pci_drv);
209 
210 /**
211  * pci_match_id - See if a pci device matches a given pci_id table
212  * @ids: array of PCI device id structures to search in
213  * @dev: the PCI device structure to match against.
214  *
215  * Used by a driver to check whether a PCI device present in the
216  * system is in its list of supported devices.  Returns the matching
217  * pci_device_id structure or %NULL if there is no match.
218  *
219  * Deprecated, don't use this as it will not catch any dynamic ids
220  * that a driver might want to check for.
221  */
pci_match_id(const struct pci_device_id * ids,struct pci_dev * dev)222 const struct pci_device_id *pci_match_id(const struct pci_device_id *ids,
223 					 struct pci_dev *dev)
224 {
225 	if (ids) {
226 		while (ids->vendor || ids->subvendor || ids->class_mask) {
227 			if (pci_match_one_device(ids, dev))
228 				return ids;
229 			ids++;
230 		}
231 	}
232 	return NULL;
233 }
234 EXPORT_SYMBOL(pci_match_id);
235 
236 static const struct pci_device_id pci_device_id_any = {
237 	.vendor = PCI_ANY_ID,
238 	.device = PCI_ANY_ID,
239 	.subvendor = PCI_ANY_ID,
240 	.subdevice = PCI_ANY_ID,
241 };
242 
243 /**
244  * pci_match_device - Tell if a PCI device structure has a matching PCI device id structure
245  * @drv: the PCI driver to match against
246  * @dev: the PCI device structure to match against
247  *
248  * Used by a driver to check whether a PCI device present in the
249  * system is in its list of supported devices.  Returns the matching
250  * pci_device_id structure or %NULL if there is no match.
251  */
pci_match_device(struct pci_driver * drv,struct pci_dev * dev)252 static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
253 						    struct pci_dev *dev)
254 {
255 	struct pci_dynid *dynid;
256 	const struct pci_device_id *found_id = NULL;
257 
258 	/* When driver_override is set, only bind to the matching driver */
259 	if (dev->driver_override && strcmp(dev->driver_override, drv->name))
260 		return NULL;
261 
262 	/* Look at the dynamic ids first, before the static ones */
263 	spin_lock(&drv->dynids.lock);
264 	list_for_each_entry(dynid, &drv->dynids.list, node) {
265 		if (pci_match_one_device(&dynid->id, dev)) {
266 			found_id = &dynid->id;
267 			break;
268 		}
269 	}
270 	spin_unlock(&drv->dynids.lock);
271 
272 	if (!found_id)
273 		found_id = pci_match_id(drv->id_table, dev);
274 
275 	/* driver_override will always match, send a dummy id */
276 	if (!found_id && dev->driver_override)
277 		found_id = &pci_device_id_any;
278 
279 	return found_id;
280 }
281 
282 struct drv_dev_and_id {
283 	struct pci_driver *drv;
284 	struct pci_dev *dev;
285 	const struct pci_device_id *id;
286 };
287 
local_pci_probe(void * _ddi)288 static long local_pci_probe(void *_ddi)
289 {
290 	struct drv_dev_and_id *ddi = _ddi;
291 	struct pci_dev *pci_dev = ddi->dev;
292 	struct pci_driver *pci_drv = ddi->drv;
293 	struct device *dev = &pci_dev->dev;
294 	int rc;
295 
296 	/*
297 	 * Unbound PCI devices are always put in D0, regardless of
298 	 * runtime PM status.  During probe, the device is set to
299 	 * active and the usage count is incremented.  If the driver
300 	 * supports runtime PM, it should call pm_runtime_put_noidle(),
301 	 * or any other runtime PM helper function decrementing the usage
302 	 * count, in its probe routine and pm_runtime_get_noresume() in
303 	 * its remove routine.
304 	 */
305 	pm_runtime_get_sync(dev);
306 	pci_dev->driver = pci_drv;
307 	rc = pci_drv->probe(pci_dev, ddi->id);
308 	if (!rc)
309 		return rc;
310 	if (rc < 0) {
311 		pci_dev->driver = NULL;
312 		pm_runtime_put_sync(dev);
313 		return rc;
314 	}
315 	/*
316 	 * Probe function should return < 0 for failure, 0 for success
317 	 * Treat values > 0 as success, but warn.
318 	 */
319 	dev_warn(dev, "Driver probe function unexpectedly returned %d\n", rc);
320 	return 0;
321 }
322 
pci_call_probe(struct pci_driver * drv,struct pci_dev * dev,const struct pci_device_id * id)323 static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
324 			  const struct pci_device_id *id)
325 {
326 	int error, node;
327 	struct drv_dev_and_id ddi = { drv, dev, id };
328 
329 	/*
330 	 * Execute driver initialization on node where the device is
331 	 * attached.  This way the driver likely allocates its local memory
332 	 * on the right node.
333 	 */
334 	node = dev_to_node(&dev->dev);
335 
336 	/*
337 	 * On NUMA systems, we are likely to call a PF probe function using
338 	 * work_on_cpu().  If that probe calls pci_enable_sriov() (which
339 	 * adds the VF devices via pci_bus_add_device()), we may re-enter
340 	 * this function to call the VF probe function.  Calling
341 	 * work_on_cpu() again will cause a lockdep warning.  Since VFs are
342 	 * always on the same node as the PF, we can work around this by
343 	 * avoiding work_on_cpu() when we're already on the correct node.
344 	 *
345 	 * Preemption is enabled, so it's theoretically unsafe to use
346 	 * numa_node_id(), but even if we run the probe function on the
347 	 * wrong node, it should be functionally correct.
348 	 */
349 	if (node >= 0 && node != numa_node_id()) {
350 		int cpu;
351 
352 		get_online_cpus();
353 		cpu = cpumask_any_and(cpumask_of_node(node), cpu_online_mask);
354 		if (cpu < nr_cpu_ids)
355 			error = work_on_cpu(cpu, local_pci_probe, &ddi);
356 		else
357 			error = local_pci_probe(&ddi);
358 		put_online_cpus();
359 	} else
360 		error = local_pci_probe(&ddi);
361 
362 	return error;
363 }
364 
365 /**
366  * __pci_device_probe - check if a driver wants to claim a specific PCI device
367  * @drv: driver to call to check if it wants the PCI device
368  * @pci_dev: PCI device being probed
369  *
370  * returns 0 on success, else error.
371  * side-effect: pci_dev->driver is set to drv when drv claims pci_dev.
372  */
__pci_device_probe(struct pci_driver * drv,struct pci_dev * pci_dev)373 static int __pci_device_probe(struct pci_driver *drv, struct pci_dev *pci_dev)
374 {
375 	const struct pci_device_id *id;
376 	int error = 0;
377 
378 	if (!pci_dev->driver && drv->probe) {
379 		error = -ENODEV;
380 
381 		id = pci_match_device(drv, pci_dev);
382 		if (id)
383 			error = pci_call_probe(drv, pci_dev, id);
384 		if (error >= 0)
385 			error = 0;
386 	}
387 	return error;
388 }
389 
pcibios_alloc_irq(struct pci_dev * dev)390 int __weak pcibios_alloc_irq(struct pci_dev *dev)
391 {
392 	return 0;
393 }
394 
pcibios_free_irq(struct pci_dev * dev)395 void __weak pcibios_free_irq(struct pci_dev *dev)
396 {
397 }
398 
pci_device_probe(struct device * dev)399 static int pci_device_probe(struct device *dev)
400 {
401 	int error;
402 	struct pci_dev *pci_dev = to_pci_dev(dev);
403 	struct pci_driver *drv = to_pci_driver(dev->driver);
404 
405 	error = pcibios_alloc_irq(pci_dev);
406 	if (error < 0)
407 		return error;
408 
409 	pci_dev_get(pci_dev);
410 	error = __pci_device_probe(drv, pci_dev);
411 	if (error) {
412 		pcibios_free_irq(pci_dev);
413 		pci_dev_put(pci_dev);
414 	}
415 
416 	return error;
417 }
418 
pci_device_remove(struct device * dev)419 static int pci_device_remove(struct device *dev)
420 {
421 	struct pci_dev *pci_dev = to_pci_dev(dev);
422 	struct pci_driver *drv = pci_dev->driver;
423 
424 	if (drv) {
425 		if (drv->remove) {
426 			pm_runtime_get_sync(dev);
427 			drv->remove(pci_dev);
428 			pm_runtime_put_noidle(dev);
429 		}
430 		pcibios_free_irq(pci_dev);
431 		pci_dev->driver = NULL;
432 	}
433 
434 	/* Undo the runtime PM settings in local_pci_probe() */
435 	pm_runtime_put_sync(dev);
436 
437 	/*
438 	 * If the device is still on, set the power state as "unknown",
439 	 * since it might change by the next time we load the driver.
440 	 */
441 	if (pci_dev->current_state == PCI_D0)
442 		pci_dev->current_state = PCI_UNKNOWN;
443 
444 	/*
445 	 * We would love to complain here if pci_dev->is_enabled is set, that
446 	 * the driver should have called pci_disable_device(), but the
447 	 * unfortunate fact is there are too many odd BIOS and bridge setups
448 	 * that don't like drivers doing that all of the time.
449 	 * Oh well, we can dream of sane hardware when we sleep, no matter how
450 	 * horrible the crap we have to deal with is when we are awake...
451 	 */
452 
453 	pci_dev_put(pci_dev);
454 	return 0;
455 }
456 
pci_device_shutdown(struct device * dev)457 static void pci_device_shutdown(struct device *dev)
458 {
459 	struct pci_dev *pci_dev = to_pci_dev(dev);
460 	struct pci_driver *drv = pci_dev->driver;
461 
462 	pm_runtime_resume(dev);
463 
464 	if (drv && drv->shutdown)
465 		drv->shutdown(pci_dev);
466 
467 	/*
468 	 * If this is a kexec reboot, turn off Bus Master bit on the
469 	 * device to tell it to not continue to do DMA. Don't touch
470 	 * devices in D3cold or unknown states.
471 	 * If it is not a kexec reboot, firmware will hit the PCI
472 	 * devices with big hammer and stop their DMA any way.
473 	 */
474 	if (kexec_in_progress && (pci_dev->current_state <= PCI_D3hot))
475 		pci_clear_master(pci_dev);
476 }
477 
478 #ifdef CONFIG_PM
479 
480 /* Auxiliary functions used for system resume and run-time resume. */
481 
482 /**
483  * pci_restore_standard_config - restore standard config registers of PCI device
484  * @pci_dev: PCI device to handle
485  */
pci_restore_standard_config(struct pci_dev * pci_dev)486 static int pci_restore_standard_config(struct pci_dev *pci_dev)
487 {
488 	pci_update_current_state(pci_dev, PCI_UNKNOWN);
489 
490 	if (pci_dev->current_state != PCI_D0) {
491 		int error = pci_set_power_state(pci_dev, PCI_D0);
492 		if (error)
493 			return error;
494 	}
495 
496 	pci_restore_state(pci_dev);
497 	return 0;
498 }
499 
500 #endif
501 
502 #ifdef CONFIG_PM_SLEEP
503 
pci_pm_default_resume_early(struct pci_dev * pci_dev)504 static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
505 {
506 	pci_power_up(pci_dev);
507 	pci_restore_state(pci_dev);
508 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
509 }
510 
511 /*
512  * Default "suspend" method for devices that have no driver provided suspend,
513  * or not even a driver at all (second part).
514  */
pci_pm_set_unknown_state(struct pci_dev * pci_dev)515 static void pci_pm_set_unknown_state(struct pci_dev *pci_dev)
516 {
517 	/*
518 	 * mark its power state as "unknown", since we don't know if
519 	 * e.g. the BIOS will change its device state when we suspend.
520 	 */
521 	if (pci_dev->current_state == PCI_D0)
522 		pci_dev->current_state = PCI_UNKNOWN;
523 }
524 
525 /*
526  * Default "resume" method for devices that have no driver provided resume,
527  * or not even a driver at all (second part).
528  */
pci_pm_reenable_device(struct pci_dev * pci_dev)529 static int pci_pm_reenable_device(struct pci_dev *pci_dev)
530 {
531 	int retval;
532 
533 	/* if the device was enabled before suspend, reenable */
534 	retval = pci_reenable_device(pci_dev);
535 	/*
536 	 * if the device was busmaster before the suspend, make it busmaster
537 	 * again
538 	 */
539 	if (pci_dev->is_busmaster)
540 		pci_set_master(pci_dev);
541 
542 	return retval;
543 }
544 
pci_legacy_suspend(struct device * dev,pm_message_t state)545 static int pci_legacy_suspend(struct device *dev, pm_message_t state)
546 {
547 	struct pci_dev *pci_dev = to_pci_dev(dev);
548 	struct pci_driver *drv = pci_dev->driver;
549 
550 	if (drv && drv->suspend) {
551 		pci_power_t prev = pci_dev->current_state;
552 		int error;
553 
554 		error = drv->suspend(pci_dev, state);
555 		suspend_report_result(drv->suspend, error);
556 		if (error)
557 			return error;
558 
559 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
560 		    && pci_dev->current_state != PCI_UNKNOWN) {
561 			WARN_ONCE(pci_dev->current_state != prev,
562 				"PCI PM: Device state not saved by %pF\n",
563 				drv->suspend);
564 		}
565 	}
566 
567 	pci_fixup_device(pci_fixup_suspend, pci_dev);
568 
569 	return 0;
570 }
571 
pci_legacy_suspend_late(struct device * dev,pm_message_t state)572 static int pci_legacy_suspend_late(struct device *dev, pm_message_t state)
573 {
574 	struct pci_dev *pci_dev = to_pci_dev(dev);
575 	struct pci_driver *drv = pci_dev->driver;
576 
577 	if (drv && drv->suspend_late) {
578 		pci_power_t prev = pci_dev->current_state;
579 		int error;
580 
581 		error = drv->suspend_late(pci_dev, state);
582 		suspend_report_result(drv->suspend_late, error);
583 		if (error)
584 			return error;
585 
586 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
587 		    && pci_dev->current_state != PCI_UNKNOWN) {
588 			WARN_ONCE(pci_dev->current_state != prev,
589 				"PCI PM: Device state not saved by %pF\n",
590 				drv->suspend_late);
591 			goto Fixup;
592 		}
593 	}
594 
595 	if (!pci_dev->state_saved)
596 		pci_save_state(pci_dev);
597 
598 	pci_pm_set_unknown_state(pci_dev);
599 
600 Fixup:
601 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
602 
603 	return 0;
604 }
605 
pci_legacy_resume_early(struct device * dev)606 static int pci_legacy_resume_early(struct device *dev)
607 {
608 	struct pci_dev *pci_dev = to_pci_dev(dev);
609 	struct pci_driver *drv = pci_dev->driver;
610 
611 	return drv && drv->resume_early ?
612 			drv->resume_early(pci_dev) : 0;
613 }
614 
pci_legacy_resume(struct device * dev)615 static int pci_legacy_resume(struct device *dev)
616 {
617 	struct pci_dev *pci_dev = to_pci_dev(dev);
618 	struct pci_driver *drv = pci_dev->driver;
619 
620 	pci_fixup_device(pci_fixup_resume, pci_dev);
621 
622 	return drv && drv->resume ?
623 			drv->resume(pci_dev) : pci_pm_reenable_device(pci_dev);
624 }
625 
626 /* Auxiliary functions used by the new power management framework */
627 
pci_pm_default_resume(struct pci_dev * pci_dev)628 static void pci_pm_default_resume(struct pci_dev *pci_dev)
629 {
630 	pci_fixup_device(pci_fixup_resume, pci_dev);
631 
632 	if (!pci_has_subordinate(pci_dev))
633 		pci_enable_wake(pci_dev, PCI_D0, false);
634 }
635 
pci_pm_default_suspend(struct pci_dev * pci_dev)636 static void pci_pm_default_suspend(struct pci_dev *pci_dev)
637 {
638 	/* Disable non-bridge devices without PM support */
639 	if (!pci_has_subordinate(pci_dev))
640 		pci_disable_enabled_device(pci_dev);
641 }
642 
pci_has_legacy_pm_support(struct pci_dev * pci_dev)643 static bool pci_has_legacy_pm_support(struct pci_dev *pci_dev)
644 {
645 	struct pci_driver *drv = pci_dev->driver;
646 	bool ret = drv && (drv->suspend || drv->suspend_late || drv->resume
647 		|| drv->resume_early);
648 
649 	/*
650 	 * Legacy PM support is used by default, so warn if the new framework is
651 	 * supported as well.  Drivers are supposed to support either the
652 	 * former, or the latter, but not both at the same time.
653 	 */
654 	WARN(ret && drv->driver.pm, "driver %s device %04x:%04x\n",
655 		drv->name, pci_dev->vendor, pci_dev->device);
656 
657 	return ret;
658 }
659 
660 /* New power management framework */
661 
pci_pm_prepare(struct device * dev)662 static int pci_pm_prepare(struct device *dev)
663 {
664 	struct device_driver *drv = dev->driver;
665 
666 	/*
667 	 * Devices having power.ignore_children set may still be necessary for
668 	 * suspending their children in the next phase of device suspend.
669 	 */
670 	if (dev->power.ignore_children)
671 		pm_runtime_resume(dev);
672 
673 	if (drv && drv->pm && drv->pm->prepare) {
674 		int error = drv->pm->prepare(dev);
675 		if (error)
676 			return error;
677 	}
678 	return pci_dev_keep_suspended(to_pci_dev(dev));
679 }
680 
pci_pm_complete(struct device * dev)681 static void pci_pm_complete(struct device *dev)
682 {
683 	struct pci_dev *pci_dev = to_pci_dev(dev);
684 
685 	pci_dev_complete_resume(pci_dev);
686 	pm_generic_complete(dev);
687 
688 	/* Resume device if platform firmware has put it in reset-power-on */
689 	if (dev->power.direct_complete && pm_resume_via_firmware()) {
690 		pci_power_t pre_sleep_state = pci_dev->current_state;
691 
692 		pci_update_current_state(pci_dev, pci_dev->current_state);
693 		if (pci_dev->current_state < pre_sleep_state)
694 			pm_request_resume(dev);
695 	}
696 }
697 
698 #else /* !CONFIG_PM_SLEEP */
699 
700 #define pci_pm_prepare	NULL
701 #define pci_pm_complete	NULL
702 
703 #endif /* !CONFIG_PM_SLEEP */
704 
705 #ifdef CONFIG_SUSPEND
706 
pci_pm_suspend(struct device * dev)707 static int pci_pm_suspend(struct device *dev)
708 {
709 	struct pci_dev *pci_dev = to_pci_dev(dev);
710 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
711 
712 	if (pci_has_legacy_pm_support(pci_dev))
713 		return pci_legacy_suspend(dev, PMSG_SUSPEND);
714 
715 	if (!pm) {
716 		pci_pm_default_suspend(pci_dev);
717 		goto Fixup;
718 	}
719 
720 	/*
721 	 * PCI devices suspended at run time need to be resumed at this point,
722 	 * because in general it is necessary to reconfigure them for system
723 	 * suspend.  Namely, if the device is supposed to wake up the system
724 	 * from the sleep state, we may need to reconfigure it for this purpose.
725 	 * In turn, if the device is not supposed to wake up the system from the
726 	 * sleep state, we'll have to prevent it from signaling wake-up.
727 	 */
728 	pm_runtime_resume(dev);
729 
730 	pci_dev->state_saved = false;
731 	if (pm->suspend) {
732 		pci_power_t prev = pci_dev->current_state;
733 		int error;
734 
735 		error = pm->suspend(dev);
736 		suspend_report_result(pm->suspend, error);
737 		if (error)
738 			return error;
739 
740 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
741 		    && pci_dev->current_state != PCI_UNKNOWN) {
742 			WARN_ONCE(pci_dev->current_state != prev,
743 				"PCI PM: State of device not saved by %pF\n",
744 				pm->suspend);
745 		}
746 	}
747 
748  Fixup:
749 	pci_fixup_device(pci_fixup_suspend, pci_dev);
750 
751 	return 0;
752 }
753 
pci_pm_suspend_noirq(struct device * dev)754 static int pci_pm_suspend_noirq(struct device *dev)
755 {
756 	struct pci_dev *pci_dev = to_pci_dev(dev);
757 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
758 
759 	if (pci_has_legacy_pm_support(pci_dev))
760 		return pci_legacy_suspend_late(dev, PMSG_SUSPEND);
761 
762 	if (!pm) {
763 		pci_save_state(pci_dev);
764 		goto Fixup;
765 	}
766 
767 	if (pm->suspend_noirq) {
768 		pci_power_t prev = pci_dev->current_state;
769 		int error;
770 
771 		error = pm->suspend_noirq(dev);
772 		suspend_report_result(pm->suspend_noirq, error);
773 		if (error)
774 			return error;
775 
776 		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
777 		    && pci_dev->current_state != PCI_UNKNOWN) {
778 			WARN_ONCE(pci_dev->current_state != prev,
779 				"PCI PM: State of device not saved by %pF\n",
780 				pm->suspend_noirq);
781 			goto Fixup;
782 		}
783 	}
784 
785 	if (!pci_dev->state_saved) {
786 		pci_save_state(pci_dev);
787 		if (pci_power_manageable(pci_dev))
788 			pci_prepare_to_sleep(pci_dev);
789 	}
790 
791 	pci_pm_set_unknown_state(pci_dev);
792 
793 	/*
794 	 * Some BIOSes from ASUS have a bug: If a USB EHCI host controller's
795 	 * PCI COMMAND register isn't 0, the BIOS assumes that the controller
796 	 * hasn't been quiesced and tries to turn it off.  If the controller
797 	 * is already in D3, this can hang or cause memory corruption.
798 	 *
799 	 * Since the value of the COMMAND register doesn't matter once the
800 	 * device has been suspended, we can safely set it to 0 here.
801 	 */
802 	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
803 		pci_write_config_word(pci_dev, PCI_COMMAND, 0);
804 
805 Fixup:
806 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
807 
808 	return 0;
809 }
810 
pci_pm_resume_noirq(struct device * dev)811 static int pci_pm_resume_noirq(struct device *dev)
812 {
813 	struct pci_dev *pci_dev = to_pci_dev(dev);
814 	struct device_driver *drv = dev->driver;
815 	int error = 0;
816 
817 	pci_pm_default_resume_early(pci_dev);
818 
819 	if (pci_has_legacy_pm_support(pci_dev))
820 		return pci_legacy_resume_early(dev);
821 
822 	if (drv && drv->pm && drv->pm->resume_noirq)
823 		error = drv->pm->resume_noirq(dev);
824 
825 	return error;
826 }
827 
pci_pm_resume(struct device * dev)828 static int pci_pm_resume(struct device *dev)
829 {
830 	struct pci_dev *pci_dev = to_pci_dev(dev);
831 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
832 	int error = 0;
833 
834 	/*
835 	 * This is necessary for the suspend error path in which resume is
836 	 * called without restoring the standard config registers of the device.
837 	 */
838 	if (pci_dev->state_saved)
839 		pci_restore_standard_config(pci_dev);
840 
841 	if (pci_has_legacy_pm_support(pci_dev))
842 		return pci_legacy_resume(dev);
843 
844 	pci_pm_default_resume(pci_dev);
845 
846 	if (pm) {
847 		if (pm->resume)
848 			error = pm->resume(dev);
849 	} else {
850 		pci_pm_reenable_device(pci_dev);
851 	}
852 
853 	return error;
854 }
855 
856 #else /* !CONFIG_SUSPEND */
857 
858 #define pci_pm_suspend		NULL
859 #define pci_pm_suspend_noirq	NULL
860 #define pci_pm_resume		NULL
861 #define pci_pm_resume_noirq	NULL
862 
863 #endif /* !CONFIG_SUSPEND */
864 
865 #ifdef CONFIG_HIBERNATE_CALLBACKS
866 
867 
868 /*
869  * pcibios_pm_ops - provide arch-specific hooks when a PCI device is doing
870  * a hibernate transition
871  */
872 struct dev_pm_ops __weak pcibios_pm_ops;
873 
pci_pm_freeze(struct device * dev)874 static int pci_pm_freeze(struct device *dev)
875 {
876 	struct pci_dev *pci_dev = to_pci_dev(dev);
877 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
878 
879 	if (pci_has_legacy_pm_support(pci_dev))
880 		return pci_legacy_suspend(dev, PMSG_FREEZE);
881 
882 	if (!pm) {
883 		pci_pm_default_suspend(pci_dev);
884 		return 0;
885 	}
886 
887 	/*
888 	 * This used to be done in pci_pm_prepare() for all devices and some
889 	 * drivers may depend on it, so do it here.  Ideally, runtime-suspended
890 	 * devices should not be touched during freeze/thaw transitions,
891 	 * however.
892 	 */
893 	pm_runtime_resume(dev);
894 
895 	pci_dev->state_saved = false;
896 	if (pm->freeze) {
897 		int error;
898 
899 		error = pm->freeze(dev);
900 		suspend_report_result(pm->freeze, error);
901 		if (error)
902 			return error;
903 	}
904 
905 	if (pcibios_pm_ops.freeze)
906 		return pcibios_pm_ops.freeze(dev);
907 
908 	return 0;
909 }
910 
pci_pm_freeze_noirq(struct device * dev)911 static int pci_pm_freeze_noirq(struct device *dev)
912 {
913 	struct pci_dev *pci_dev = to_pci_dev(dev);
914 	struct device_driver *drv = dev->driver;
915 
916 	if (pci_has_legacy_pm_support(pci_dev))
917 		return pci_legacy_suspend_late(dev, PMSG_FREEZE);
918 
919 	if (drv && drv->pm && drv->pm->freeze_noirq) {
920 		int error;
921 
922 		error = drv->pm->freeze_noirq(dev);
923 		suspend_report_result(drv->pm->freeze_noirq, error);
924 		if (error)
925 			return error;
926 	}
927 
928 	if (!pci_dev->state_saved)
929 		pci_save_state(pci_dev);
930 
931 	pci_pm_set_unknown_state(pci_dev);
932 
933 	if (pcibios_pm_ops.freeze_noirq)
934 		return pcibios_pm_ops.freeze_noirq(dev);
935 
936 	return 0;
937 }
938 
pci_pm_thaw_noirq(struct device * dev)939 static int pci_pm_thaw_noirq(struct device *dev)
940 {
941 	struct pci_dev *pci_dev = to_pci_dev(dev);
942 	struct device_driver *drv = dev->driver;
943 	int error = 0;
944 
945 	if (pcibios_pm_ops.thaw_noirq) {
946 		error = pcibios_pm_ops.thaw_noirq(dev);
947 		if (error)
948 			return error;
949 	}
950 
951 	if (pci_has_legacy_pm_support(pci_dev))
952 		return pci_legacy_resume_early(dev);
953 
954 	/*
955 	 * pci_restore_state() requires the device to be in D0 (because of MSI
956 	 * restoration among other things), so force it into D0 in case the
957 	 * driver's "freeze" callbacks put it into a low-power state directly.
958 	 */
959 	pci_set_power_state(pci_dev, PCI_D0);
960 	pci_restore_state(pci_dev);
961 
962 	if (drv && drv->pm && drv->pm->thaw_noirq)
963 		error = drv->pm->thaw_noirq(dev);
964 
965 	return error;
966 }
967 
pci_pm_thaw(struct device * dev)968 static int pci_pm_thaw(struct device *dev)
969 {
970 	struct pci_dev *pci_dev = to_pci_dev(dev);
971 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
972 	int error = 0;
973 
974 	if (pcibios_pm_ops.thaw) {
975 		error = pcibios_pm_ops.thaw(dev);
976 		if (error)
977 			return error;
978 	}
979 
980 	if (pci_has_legacy_pm_support(pci_dev))
981 		return pci_legacy_resume(dev);
982 
983 	if (pm) {
984 		if (pm->thaw)
985 			error = pm->thaw(dev);
986 	} else {
987 		pci_pm_reenable_device(pci_dev);
988 	}
989 
990 	pci_dev->state_saved = false;
991 
992 	return error;
993 }
994 
pci_pm_poweroff(struct device * dev)995 static int pci_pm_poweroff(struct device *dev)
996 {
997 	struct pci_dev *pci_dev = to_pci_dev(dev);
998 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
999 
1000 	if (pci_has_legacy_pm_support(pci_dev))
1001 		return pci_legacy_suspend(dev, PMSG_HIBERNATE);
1002 
1003 	if (!pm) {
1004 		pci_pm_default_suspend(pci_dev);
1005 		goto Fixup;
1006 	}
1007 
1008 	/* The reason to do that is the same as in pci_pm_suspend(). */
1009 	pm_runtime_resume(dev);
1010 
1011 	pci_dev->state_saved = false;
1012 	if (pm->poweroff) {
1013 		int error;
1014 
1015 		error = pm->poweroff(dev);
1016 		suspend_report_result(pm->poweroff, error);
1017 		if (error)
1018 			return error;
1019 	}
1020 
1021  Fixup:
1022 	pci_fixup_device(pci_fixup_suspend, pci_dev);
1023 
1024 	if (pcibios_pm_ops.poweroff)
1025 		return pcibios_pm_ops.poweroff(dev);
1026 
1027 	return 0;
1028 }
1029 
pci_pm_poweroff_noirq(struct device * dev)1030 static int pci_pm_poweroff_noirq(struct device *dev)
1031 {
1032 	struct pci_dev *pci_dev = to_pci_dev(dev);
1033 	struct device_driver *drv = dev->driver;
1034 
1035 	if (pci_has_legacy_pm_support(to_pci_dev(dev)))
1036 		return pci_legacy_suspend_late(dev, PMSG_HIBERNATE);
1037 
1038 	if (!drv || !drv->pm) {
1039 		pci_fixup_device(pci_fixup_suspend_late, pci_dev);
1040 		return 0;
1041 	}
1042 
1043 	if (drv->pm->poweroff_noirq) {
1044 		int error;
1045 
1046 		error = drv->pm->poweroff_noirq(dev);
1047 		suspend_report_result(drv->pm->poweroff_noirq, error);
1048 		if (error)
1049 			return error;
1050 	}
1051 
1052 	if (!pci_dev->state_saved && !pci_has_subordinate(pci_dev))
1053 		pci_prepare_to_sleep(pci_dev);
1054 
1055 	/*
1056 	 * The reason for doing this here is the same as for the analogous code
1057 	 * in pci_pm_suspend_noirq().
1058 	 */
1059 	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
1060 		pci_write_config_word(pci_dev, PCI_COMMAND, 0);
1061 
1062 	pci_fixup_device(pci_fixup_suspend_late, pci_dev);
1063 
1064 	if (pcibios_pm_ops.poweroff_noirq)
1065 		return pcibios_pm_ops.poweroff_noirq(dev);
1066 
1067 	return 0;
1068 }
1069 
pci_pm_restore_noirq(struct device * dev)1070 static int pci_pm_restore_noirq(struct device *dev)
1071 {
1072 	struct pci_dev *pci_dev = to_pci_dev(dev);
1073 	struct device_driver *drv = dev->driver;
1074 	int error = 0;
1075 
1076 	if (pcibios_pm_ops.restore_noirq) {
1077 		error = pcibios_pm_ops.restore_noirq(dev);
1078 		if (error)
1079 			return error;
1080 	}
1081 
1082 	pci_pm_default_resume_early(pci_dev);
1083 
1084 	if (pci_has_legacy_pm_support(pci_dev))
1085 		return pci_legacy_resume_early(dev);
1086 
1087 	if (drv && drv->pm && drv->pm->restore_noirq)
1088 		error = drv->pm->restore_noirq(dev);
1089 
1090 	return error;
1091 }
1092 
pci_pm_restore(struct device * dev)1093 static int pci_pm_restore(struct device *dev)
1094 {
1095 	struct pci_dev *pci_dev = to_pci_dev(dev);
1096 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1097 	int error = 0;
1098 
1099 	if (pcibios_pm_ops.restore) {
1100 		error = pcibios_pm_ops.restore(dev);
1101 		if (error)
1102 			return error;
1103 	}
1104 
1105 	/*
1106 	 * This is necessary for the hibernation error path in which restore is
1107 	 * called without restoring the standard config registers of the device.
1108 	 */
1109 	if (pci_dev->state_saved)
1110 		pci_restore_standard_config(pci_dev);
1111 
1112 	if (pci_has_legacy_pm_support(pci_dev))
1113 		return pci_legacy_resume(dev);
1114 
1115 	pci_pm_default_resume(pci_dev);
1116 
1117 	if (pm) {
1118 		if (pm->restore)
1119 			error = pm->restore(dev);
1120 	} else {
1121 		pci_pm_reenable_device(pci_dev);
1122 	}
1123 
1124 	return error;
1125 }
1126 
1127 #else /* !CONFIG_HIBERNATE_CALLBACKS */
1128 
1129 #define pci_pm_freeze		NULL
1130 #define pci_pm_freeze_noirq	NULL
1131 #define pci_pm_thaw		NULL
1132 #define pci_pm_thaw_noirq	NULL
1133 #define pci_pm_poweroff		NULL
1134 #define pci_pm_poweroff_noirq	NULL
1135 #define pci_pm_restore		NULL
1136 #define pci_pm_restore_noirq	NULL
1137 
1138 #endif /* !CONFIG_HIBERNATE_CALLBACKS */
1139 
1140 #ifdef CONFIG_PM
1141 
pci_pm_runtime_suspend(struct device * dev)1142 static int pci_pm_runtime_suspend(struct device *dev)
1143 {
1144 	struct pci_dev *pci_dev = to_pci_dev(dev);
1145 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1146 	pci_power_t prev = pci_dev->current_state;
1147 	int error;
1148 
1149 	/*
1150 	 * If pci_dev->driver is not set (unbound), the device should
1151 	 * always remain in D0 regardless of the runtime PM status
1152 	 */
1153 	if (!pci_dev->driver)
1154 		return 0;
1155 
1156 	if (!pm || !pm->runtime_suspend)
1157 		return -ENOSYS;
1158 
1159 	pci_dev->state_saved = false;
1160 	error = pm->runtime_suspend(dev);
1161 	if (error) {
1162 		/*
1163 		 * -EBUSY and -EAGAIN is used to request the runtime PM core
1164 		 * to schedule a new suspend, so log the event only with debug
1165 		 * log level.
1166 		 */
1167 		if (error == -EBUSY || error == -EAGAIN)
1168 			dev_dbg(dev, "can't suspend now (%pf returned %d)\n",
1169 				pm->runtime_suspend, error);
1170 		else
1171 			dev_err(dev, "can't suspend (%pf returned %d)\n",
1172 				pm->runtime_suspend, error);
1173 
1174 		return error;
1175 	}
1176 
1177 	pci_fixup_device(pci_fixup_suspend, pci_dev);
1178 
1179 	if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
1180 	    && pci_dev->current_state != PCI_UNKNOWN) {
1181 		WARN_ONCE(pci_dev->current_state != prev,
1182 			"PCI PM: State of device not saved by %pF\n",
1183 			pm->runtime_suspend);
1184 		return 0;
1185 	}
1186 
1187 	if (!pci_dev->state_saved) {
1188 		pci_save_state(pci_dev);
1189 		pci_finish_runtime_suspend(pci_dev);
1190 	}
1191 
1192 	return 0;
1193 }
1194 
pci_pm_runtime_resume(struct device * dev)1195 static int pci_pm_runtime_resume(struct device *dev)
1196 {
1197 	int rc;
1198 	struct pci_dev *pci_dev = to_pci_dev(dev);
1199 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1200 
1201 	/*
1202 	 * If pci_dev->driver is not set (unbound), the device should
1203 	 * always remain in D0 regardless of the runtime PM status
1204 	 */
1205 	if (!pci_dev->driver)
1206 		return 0;
1207 
1208 	if (!pm || !pm->runtime_resume)
1209 		return -ENOSYS;
1210 
1211 	pci_restore_standard_config(pci_dev);
1212 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
1213 	__pci_enable_wake(pci_dev, PCI_D0, true, false);
1214 	pci_fixup_device(pci_fixup_resume, pci_dev);
1215 
1216 	rc = pm->runtime_resume(dev);
1217 
1218 	pci_dev->runtime_d3cold = false;
1219 
1220 	return rc;
1221 }
1222 
pci_pm_runtime_idle(struct device * dev)1223 static int pci_pm_runtime_idle(struct device *dev)
1224 {
1225 	struct pci_dev *pci_dev = to_pci_dev(dev);
1226 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1227 	int ret = 0;
1228 
1229 	/*
1230 	 * If pci_dev->driver is not set (unbound), the device should
1231 	 * always remain in D0 regardless of the runtime PM status
1232 	 */
1233 	if (!pci_dev->driver)
1234 		return 0;
1235 
1236 	if (!pm)
1237 		return -ENOSYS;
1238 
1239 	if (pm->runtime_idle)
1240 		ret = pm->runtime_idle(dev);
1241 
1242 	return ret;
1243 }
1244 
1245 static const struct dev_pm_ops pci_dev_pm_ops = {
1246 	.prepare = pci_pm_prepare,
1247 	.complete = pci_pm_complete,
1248 	.suspend = pci_pm_suspend,
1249 	.resume = pci_pm_resume,
1250 	.freeze = pci_pm_freeze,
1251 	.thaw = pci_pm_thaw,
1252 	.poweroff = pci_pm_poweroff,
1253 	.restore = pci_pm_restore,
1254 	.suspend_noirq = pci_pm_suspend_noirq,
1255 	.resume_noirq = pci_pm_resume_noirq,
1256 	.freeze_noirq = pci_pm_freeze_noirq,
1257 	.thaw_noirq = pci_pm_thaw_noirq,
1258 	.poweroff_noirq = pci_pm_poweroff_noirq,
1259 	.restore_noirq = pci_pm_restore_noirq,
1260 	.runtime_suspend = pci_pm_runtime_suspend,
1261 	.runtime_resume = pci_pm_runtime_resume,
1262 	.runtime_idle = pci_pm_runtime_idle,
1263 };
1264 
1265 #define PCI_PM_OPS_PTR	(&pci_dev_pm_ops)
1266 
1267 #else /* !CONFIG_PM */
1268 
1269 #define pci_pm_runtime_suspend	NULL
1270 #define pci_pm_runtime_resume	NULL
1271 #define pci_pm_runtime_idle	NULL
1272 
1273 #define PCI_PM_OPS_PTR	NULL
1274 
1275 #endif /* !CONFIG_PM */
1276 
1277 /**
1278  * __pci_register_driver - register a new pci driver
1279  * @drv: the driver structure to register
1280  * @owner: owner module of drv
1281  * @mod_name: module name string
1282  *
1283  * Adds the driver structure to the list of registered drivers.
1284  * Returns a negative value on error, otherwise 0.
1285  * If no error occurred, the driver remains registered even if
1286  * no device was claimed during registration.
1287  */
__pci_register_driver(struct pci_driver * drv,struct module * owner,const char * mod_name)1288 int __pci_register_driver(struct pci_driver *drv, struct module *owner,
1289 			  const char *mod_name)
1290 {
1291 	/* initialize common driver fields */
1292 	drv->driver.name = drv->name;
1293 	drv->driver.bus = &pci_bus_type;
1294 	drv->driver.owner = owner;
1295 	drv->driver.mod_name = mod_name;
1296 
1297 	spin_lock_init(&drv->dynids.lock);
1298 	INIT_LIST_HEAD(&drv->dynids.list);
1299 
1300 	/* register with core */
1301 	return driver_register(&drv->driver);
1302 }
1303 EXPORT_SYMBOL(__pci_register_driver);
1304 
1305 /**
1306  * pci_unregister_driver - unregister a pci driver
1307  * @drv: the driver structure to unregister
1308  *
1309  * Deletes the driver structure from the list of registered PCI drivers,
1310  * gives it a chance to clean up by calling its remove() function for
1311  * each device it was responsible for, and marks those devices as
1312  * driverless.
1313  */
1314 
pci_unregister_driver(struct pci_driver * drv)1315 void pci_unregister_driver(struct pci_driver *drv)
1316 {
1317 	driver_unregister(&drv->driver);
1318 	pci_free_dynids(drv);
1319 }
1320 EXPORT_SYMBOL(pci_unregister_driver);
1321 
1322 static struct pci_driver pci_compat_driver = {
1323 	.name = "compat"
1324 };
1325 
1326 /**
1327  * pci_dev_driver - get the pci_driver of a device
1328  * @dev: the device to query
1329  *
1330  * Returns the appropriate pci_driver structure or %NULL if there is no
1331  * registered driver for the device.
1332  */
pci_dev_driver(const struct pci_dev * dev)1333 struct pci_driver *pci_dev_driver(const struct pci_dev *dev)
1334 {
1335 	if (dev->driver)
1336 		return dev->driver;
1337 	else {
1338 		int i;
1339 		for (i = 0; i <= PCI_ROM_RESOURCE; i++)
1340 			if (dev->resource[i].flags & IORESOURCE_BUSY)
1341 				return &pci_compat_driver;
1342 	}
1343 	return NULL;
1344 }
1345 EXPORT_SYMBOL(pci_dev_driver);
1346 
1347 /**
1348  * pci_bus_match - Tell if a PCI device structure has a matching PCI device id structure
1349  * @dev: the PCI device structure to match against
1350  * @drv: the device driver to search for matching PCI device id structures
1351  *
1352  * Used by a driver to check whether a PCI device present in the
1353  * system is in its list of supported devices. Returns the matching
1354  * pci_device_id structure or %NULL if there is no match.
1355  */
pci_bus_match(struct device * dev,struct device_driver * drv)1356 static int pci_bus_match(struct device *dev, struct device_driver *drv)
1357 {
1358 	struct pci_dev *pci_dev = to_pci_dev(dev);
1359 	struct pci_driver *pci_drv;
1360 	const struct pci_device_id *found_id;
1361 
1362 	if (!pci_dev->match_driver)
1363 		return 0;
1364 
1365 	pci_drv = to_pci_driver(drv);
1366 	found_id = pci_match_device(pci_drv, pci_dev);
1367 	if (found_id)
1368 		return 1;
1369 
1370 	return 0;
1371 }
1372 
1373 /**
1374  * pci_dev_get - increments the reference count of the pci device structure
1375  * @dev: the device being referenced
1376  *
1377  * Each live reference to a device should be refcounted.
1378  *
1379  * Drivers for PCI devices should normally record such references in
1380  * their probe() methods, when they bind to a device, and release
1381  * them by calling pci_dev_put(), in their disconnect() methods.
1382  *
1383  * A pointer to the device with the incremented reference counter is returned.
1384  */
pci_dev_get(struct pci_dev * dev)1385 struct pci_dev *pci_dev_get(struct pci_dev *dev)
1386 {
1387 	if (dev)
1388 		get_device(&dev->dev);
1389 	return dev;
1390 }
1391 EXPORT_SYMBOL(pci_dev_get);
1392 
1393 /**
1394  * pci_dev_put - release a use of the pci device structure
1395  * @dev: device that's been disconnected
1396  *
1397  * Must be called when a user of a device is finished with it.  When the last
1398  * user of the device calls this function, the memory of the device is freed.
1399  */
pci_dev_put(struct pci_dev * dev)1400 void pci_dev_put(struct pci_dev *dev)
1401 {
1402 	if (dev)
1403 		put_device(&dev->dev);
1404 }
1405 EXPORT_SYMBOL(pci_dev_put);
1406 
pci_uevent(struct device * dev,struct kobj_uevent_env * env)1407 static int pci_uevent(struct device *dev, struct kobj_uevent_env *env)
1408 {
1409 	struct pci_dev *pdev;
1410 
1411 	if (!dev)
1412 		return -ENODEV;
1413 
1414 	pdev = to_pci_dev(dev);
1415 
1416 	if (add_uevent_var(env, "PCI_CLASS=%04X", pdev->class))
1417 		return -ENOMEM;
1418 
1419 	if (add_uevent_var(env, "PCI_ID=%04X:%04X", pdev->vendor, pdev->device))
1420 		return -ENOMEM;
1421 
1422 	if (add_uevent_var(env, "PCI_SUBSYS_ID=%04X:%04X", pdev->subsystem_vendor,
1423 			   pdev->subsystem_device))
1424 		return -ENOMEM;
1425 
1426 	if (add_uevent_var(env, "PCI_SLOT_NAME=%s", pci_name(pdev)))
1427 		return -ENOMEM;
1428 
1429 	if (add_uevent_var(env, "MODALIAS=pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02X",
1430 			   pdev->vendor, pdev->device,
1431 			   pdev->subsystem_vendor, pdev->subsystem_device,
1432 			   (u8)(pdev->class >> 16), (u8)(pdev->class >> 8),
1433 			   (u8)(pdev->class)))
1434 		return -ENOMEM;
1435 
1436 	return 0;
1437 }
1438 
1439 struct bus_type pci_bus_type = {
1440 	.name		= "pci",
1441 	.match		= pci_bus_match,
1442 	.uevent		= pci_uevent,
1443 	.probe		= pci_device_probe,
1444 	.remove		= pci_device_remove,
1445 	.shutdown	= pci_device_shutdown,
1446 	.dev_groups	= pci_dev_groups,
1447 	.bus_groups	= pci_bus_groups,
1448 	.drv_groups	= pci_drv_groups,
1449 	.pm		= PCI_PM_OPS_PTR,
1450 };
1451 EXPORT_SYMBOL(pci_bus_type);
1452 
pci_driver_init(void)1453 static int __init pci_driver_init(void)
1454 {
1455 	return bus_register(&pci_bus_type);
1456 }
1457 postcore_initcall(pci_driver_init);
1458