1// SPDX-License-Identifier: GPL-2.0
2/*
3 * (C) Copyright 2002-2004, 2007 Greg Kroah-Hartman <greg@kroah.com>
4 * (C) Copyright 2007 Novell Inc.
5 */
6
7#include <linux/pci.h>
8#include <linux/module.h>
9#include <linux/init.h>
10#include <linux/device.h>
11#include <linux/mempolicy.h>
12#include <linux/string.h>
13#include <linux/slab.h>
14#include <linux/sched.h>
15#include <linux/sched/isolation.h>
16#include <linux/cpu.h>
17#include <linux/pm_runtime.h>
18#include <linux/suspend.h>
19#include <linux/kexec.h>
20#include <linux/of_device.h>
21#include <linux/acpi.h>
22#include <linux/dma-map-ops.h>
23#include <linux/iommu.h>
24#include "pci.h"
25#include "pcie/portdrv.h"
26
27struct pci_dynid {
28 struct list_head node;
29 struct pci_device_id id;
30};
31
32/**
33 * pci_add_dynid - add a new PCI device ID to this driver and re-probe devices
34 * @drv: target pci driver
35 * @vendor: PCI vendor ID
36 * @device: PCI device ID
37 * @subvendor: PCI subvendor ID
38 * @subdevice: PCI subdevice ID
39 * @class: PCI class
40 * @class_mask: PCI class mask
41 * @driver_data: private driver data
42 *
43 * Adds a new dynamic pci device ID to this driver and causes the
44 * driver to probe for all devices again. @drv must have been
45 * registered prior to calling this function.
46 *
47 * CONTEXT:
48 * Does GFP_KERNEL allocation.
49 *
50 * RETURNS:
51 * 0 on success, -errno on failure.
52 */
53int pci_add_dynid(struct pci_driver *drv,
54 unsigned int vendor, unsigned int device,
55 unsigned int subvendor, unsigned int subdevice,
56 unsigned int class, unsigned int class_mask,
57 unsigned long driver_data)
58{
59 struct pci_dynid *dynid;
60
61 dynid = kzalloc(size: sizeof(*dynid), GFP_KERNEL);
62 if (!dynid)
63 return -ENOMEM;
64
65 dynid->id.vendor = vendor;
66 dynid->id.device = device;
67 dynid->id.subvendor = subvendor;
68 dynid->id.subdevice = subdevice;
69 dynid->id.class = class;
70 dynid->id.class_mask = class_mask;
71 dynid->id.driver_data = driver_data;
72
73 spin_lock(lock: &drv->dynids.lock);
74 list_add_tail(new: &dynid->node, head: &drv->dynids.list);
75 spin_unlock(lock: &drv->dynids.lock);
76
77 return driver_attach(drv: &drv->driver);
78}
79EXPORT_SYMBOL_GPL(pci_add_dynid);
80
81static void pci_free_dynids(struct pci_driver *drv)
82{
83 struct pci_dynid *dynid, *n;
84
85 spin_lock(lock: &drv->dynids.lock);
86 list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
87 list_del(entry: &dynid->node);
88 kfree(objp: dynid);
89 }
90 spin_unlock(lock: &drv->dynids.lock);
91}
92
93/**
94 * pci_match_id - See if a PCI device matches a given pci_id table
95 * @ids: array of PCI device ID structures to search in
96 * @dev: the PCI device structure to match against.
97 *
98 * Used by a driver to check whether a PCI device is in its list of
99 * supported devices. Returns the matching pci_device_id structure or
100 * %NULL if there is no match.
101 *
102 * Deprecated; don't use this as it will not catch any dynamic IDs
103 * that a driver might want to check for.
104 */
105const struct pci_device_id *pci_match_id(const struct pci_device_id *ids,
106 struct pci_dev *dev)
107{
108 if (ids) {
109 while (ids->vendor || ids->subvendor || ids->class_mask) {
110 if (pci_match_one_device(id: ids, dev))
111 return ids;
112 ids++;
113 }
114 }
115 return NULL;
116}
117EXPORT_SYMBOL(pci_match_id);
118
119static const struct pci_device_id pci_device_id_any = {
120 .vendor = PCI_ANY_ID,
121 .device = PCI_ANY_ID,
122 .subvendor = PCI_ANY_ID,
123 .subdevice = PCI_ANY_ID,
124};
125
126/**
127 * pci_match_device - See if a device matches a driver's list of IDs
128 * @drv: the PCI driver to match against
129 * @dev: the PCI device structure to match against
130 *
131 * Used by a driver to check whether a PCI device is in its list of
132 * supported devices or in the dynids list, which may have been augmented
133 * via the sysfs "new_id" file. Returns the matching pci_device_id
134 * structure or %NULL if there is no match.
135 */
136static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
137 struct pci_dev *dev)
138{
139 struct pci_dynid *dynid;
140 const struct pci_device_id *found_id = NULL, *ids;
141
142 /* When driver_override is set, only bind to the matching driver */
143 if (dev->driver_override && strcmp(dev->driver_override, drv->name))
144 return NULL;
145
146 /* Look at the dynamic ids first, before the static ones */
147 spin_lock(lock: &drv->dynids.lock);
148 list_for_each_entry(dynid, &drv->dynids.list, node) {
149 if (pci_match_one_device(id: &dynid->id, dev)) {
150 found_id = &dynid->id;
151 break;
152 }
153 }
154 spin_unlock(lock: &drv->dynids.lock);
155
156 if (found_id)
157 return found_id;
158
159 for (ids = drv->id_table; (found_id = pci_match_id(ids, dev));
160 ids = found_id + 1) {
161 /*
162 * The match table is split based on driver_override.
163 * In case override_only was set, enforce driver_override
164 * matching.
165 */
166 if (found_id->override_only) {
167 if (dev->driver_override)
168 return found_id;
169 } else {
170 return found_id;
171 }
172 }
173
174 /* driver_override will always match, send a dummy id */
175 if (dev->driver_override)
176 return &pci_device_id_any;
177 return NULL;
178}
179
180/**
181 * new_id_store - sysfs frontend to pci_add_dynid()
182 * @driver: target device driver
183 * @buf: buffer for scanning device ID data
184 * @count: input size
185 *
186 * Allow PCI IDs to be added to an existing driver via sysfs.
187 */
188static ssize_t new_id_store(struct device_driver *driver, const char *buf,
189 size_t count)
190{
191 struct pci_driver *pdrv = to_pci_driver(drv: driver);
192 const struct pci_device_id *ids = pdrv->id_table;
193 u32 vendor, device, subvendor = PCI_ANY_ID,
194 subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
195 unsigned long driver_data = 0;
196 int fields;
197 int retval = 0;
198
199 fields = sscanf(buf, "%x %x %x %x %x %x %lx",
200 &vendor, &device, &subvendor, &subdevice,
201 &class, &class_mask, &driver_data);
202 if (fields < 2)
203 return -EINVAL;
204
205 if (fields != 7) {
206 struct pci_dev *pdev = kzalloc(size: sizeof(*pdev), GFP_KERNEL);
207 if (!pdev)
208 return -ENOMEM;
209
210 pdev->vendor = vendor;
211 pdev->device = device;
212 pdev->subsystem_vendor = subvendor;
213 pdev->subsystem_device = subdevice;
214 pdev->class = class;
215
216 if (pci_match_device(drv: pdrv, dev: pdev))
217 retval = -EEXIST;
218
219 kfree(objp: pdev);
220
221 if (retval)
222 return retval;
223 }
224
225 /* Only accept driver_data values that match an existing id_table
226 entry */
227 if (ids) {
228 retval = -EINVAL;
229 while (ids->vendor || ids->subvendor || ids->class_mask) {
230 if (driver_data == ids->driver_data) {
231 retval = 0;
232 break;
233 }
234 ids++;
235 }
236 if (retval) /* No match */
237 return retval;
238 }
239
240 retval = pci_add_dynid(pdrv, vendor, device, subvendor, subdevice,
241 class, class_mask, driver_data);
242 if (retval)
243 return retval;
244 return count;
245}
246static DRIVER_ATTR_WO(new_id);
247
248/**
249 * remove_id_store - remove a PCI device ID from this driver
250 * @driver: target device driver
251 * @buf: buffer for scanning device ID data
252 * @count: input size
253 *
254 * Removes a dynamic pci device ID to this driver.
255 */
256static ssize_t remove_id_store(struct device_driver *driver, const char *buf,
257 size_t count)
258{
259 struct pci_dynid *dynid, *n;
260 struct pci_driver *pdrv = to_pci_driver(drv: driver);
261 u32 vendor, device, subvendor = PCI_ANY_ID,
262 subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
263 int fields;
264 size_t retval = -ENODEV;
265
266 fields = sscanf(buf, "%x %x %x %x %x %x",
267 &vendor, &device, &subvendor, &subdevice,
268 &class, &class_mask);
269 if (fields < 2)
270 return -EINVAL;
271
272 spin_lock(lock: &pdrv->dynids.lock);
273 list_for_each_entry_safe(dynid, n, &pdrv->dynids.list, node) {
274 struct pci_device_id *id = &dynid->id;
275 if ((id->vendor == vendor) &&
276 (id->device == device) &&
277 (subvendor == PCI_ANY_ID || id->subvendor == subvendor) &&
278 (subdevice == PCI_ANY_ID || id->subdevice == subdevice) &&
279 !((id->class ^ class) & class_mask)) {
280 list_del(entry: &dynid->node);
281 kfree(objp: dynid);
282 retval = count;
283 break;
284 }
285 }
286 spin_unlock(lock: &pdrv->dynids.lock);
287
288 return retval;
289}
290static DRIVER_ATTR_WO(remove_id);
291
292static struct attribute *pci_drv_attrs[] = {
293 &driver_attr_new_id.attr,
294 &driver_attr_remove_id.attr,
295 NULL,
296};
297ATTRIBUTE_GROUPS(pci_drv);
298
299struct drv_dev_and_id {
300 struct pci_driver *drv;
301 struct pci_dev *dev;
302 const struct pci_device_id *id;
303};
304
305static long local_pci_probe(void *_ddi)
306{
307 struct drv_dev_and_id *ddi = _ddi;
308 struct pci_dev *pci_dev = ddi->dev;
309 struct pci_driver *pci_drv = ddi->drv;
310 struct device *dev = &pci_dev->dev;
311 int rc;
312
313 /*
314 * Unbound PCI devices are always put in D0, regardless of
315 * runtime PM status. During probe, the device is set to
316 * active and the usage count is incremented. If the driver
317 * supports runtime PM, it should call pm_runtime_put_noidle(),
318 * or any other runtime PM helper function decrementing the usage
319 * count, in its probe routine and pm_runtime_get_noresume() in
320 * its remove routine.
321 */
322 pm_runtime_get_sync(dev);
323 pci_dev->driver = pci_drv;
324 rc = pci_drv->probe(pci_dev, ddi->id);
325 if (!rc)
326 return rc;
327 if (rc < 0) {
328 pci_dev->driver = NULL;
329 pm_runtime_put_sync(dev);
330 return rc;
331 }
332 /*
333 * Probe function should return < 0 for failure, 0 for success
334 * Treat values > 0 as success, but warn.
335 */
336 pci_warn(pci_dev, "Driver probe function unexpectedly returned %d\n",
337 rc);
338 return 0;
339}
340
341static bool pci_physfn_is_probed(struct pci_dev *dev)
342{
343#ifdef CONFIG_PCI_IOV
344 return dev->is_virtfn && dev->physfn->is_probed;
345#else
346 return false;
347#endif
348}
349
350static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
351 const struct pci_device_id *id)
352{
353 int error, node, cpu;
354 struct drv_dev_and_id ddi = { drv, dev, id };
355
356 /*
357 * Execute driver initialization on node where the device is
358 * attached. This way the driver likely allocates its local memory
359 * on the right node.
360 */
361 node = dev_to_node(dev: &dev->dev);
362 dev->is_probed = 1;
363
364 cpu_hotplug_disable();
365
366 /*
367 * Prevent nesting work_on_cpu() for the case where a Virtual Function
368 * device is probed from work_on_cpu() of the Physical device.
369 */
370 if (node < 0 || node >= MAX_NUMNODES || !node_online(node) ||
371 pci_physfn_is_probed(dev)) {
372 cpu = nr_cpu_ids;
373 } else {
374 cpumask_var_t wq_domain_mask;
375
376 if (!zalloc_cpumask_var(mask: &wq_domain_mask, GFP_KERNEL)) {
377 error = -ENOMEM;
378 goto out;
379 }
380 cpumask_and(dstp: wq_domain_mask,
381 src1p: housekeeping_cpumask(type: HK_TYPE_WQ),
382 src2p: housekeeping_cpumask(type: HK_TYPE_DOMAIN));
383
384 cpu = cpumask_any_and(cpumask_of_node(node),
385 wq_domain_mask);
386 free_cpumask_var(mask: wq_domain_mask);
387 }
388
389 if (cpu < nr_cpu_ids)
390 error = work_on_cpu(cpu, local_pci_probe, &ddi);
391 else
392 error = local_pci_probe(ddi: &ddi);
393out:
394 dev->is_probed = 0;
395 cpu_hotplug_enable();
396 return error;
397}
398
399/**
400 * __pci_device_probe - check if a driver wants to claim a specific PCI device
401 * @drv: driver to call to check if it wants the PCI device
402 * @pci_dev: PCI device being probed
403 *
404 * returns 0 on success, else error.
405 * side-effect: pci_dev->driver is set to drv when drv claims pci_dev.
406 */
407static int __pci_device_probe(struct pci_driver *drv, struct pci_dev *pci_dev)
408{
409 const struct pci_device_id *id;
410 int error = 0;
411
412 if (drv->probe) {
413 error = -ENODEV;
414
415 id = pci_match_device(drv, dev: pci_dev);
416 if (id)
417 error = pci_call_probe(drv, dev: pci_dev, id);
418 }
419 return error;
420}
421
422int __weak pcibios_alloc_irq(struct pci_dev *dev)
423{
424 return 0;
425}
426
427void __weak pcibios_free_irq(struct pci_dev *dev)
428{
429}
430
431#ifdef CONFIG_PCI_IOV
432static inline bool pci_device_can_probe(struct pci_dev *pdev)
433{
434 return (!pdev->is_virtfn || pdev->physfn->sriov->drivers_autoprobe ||
435 pdev->driver_override);
436}
437#else
438static inline bool pci_device_can_probe(struct pci_dev *pdev)
439{
440 return true;
441}
442#endif
443
444static int pci_device_probe(struct device *dev)
445{
446 int error;
447 struct pci_dev *pci_dev = to_pci_dev(dev);
448 struct pci_driver *drv = to_pci_driver(drv: dev->driver);
449
450 if (!pci_device_can_probe(pdev: pci_dev))
451 return -ENODEV;
452
453 pci_assign_irq(dev: pci_dev);
454
455 error = pcibios_alloc_irq(dev: pci_dev);
456 if (error < 0)
457 return error;
458
459 pci_dev_get(dev: pci_dev);
460 error = __pci_device_probe(drv, pci_dev);
461 if (error) {
462 pcibios_free_irq(dev: pci_dev);
463 pci_dev_put(dev: pci_dev);
464 }
465
466 return error;
467}
468
469static void pci_device_remove(struct device *dev)
470{
471 struct pci_dev *pci_dev = to_pci_dev(dev);
472 struct pci_driver *drv = pci_dev->driver;
473
474 if (drv->remove) {
475 pm_runtime_get_sync(dev);
476 drv->remove(pci_dev);
477 pm_runtime_put_noidle(dev);
478 }
479 pcibios_free_irq(dev: pci_dev);
480 pci_dev->driver = NULL;
481 pci_iov_remove(dev: pci_dev);
482
483 /* Undo the runtime PM settings in local_pci_probe() */
484 pm_runtime_put_sync(dev);
485
486 /*
487 * If the device is still on, set the power state as "unknown",
488 * since it might change by the next time we load the driver.
489 */
490 if (pci_dev->current_state == PCI_D0)
491 pci_dev->current_state = PCI_UNKNOWN;
492
493 /*
494 * We would love to complain here if pci_dev->is_enabled is set, that
495 * the driver should have called pci_disable_device(), but the
496 * unfortunate fact is there are too many odd BIOS and bridge setups
497 * that don't like drivers doing that all of the time.
498 * Oh well, we can dream of sane hardware when we sleep, no matter how
499 * horrible the crap we have to deal with is when we are awake...
500 */
501
502 pci_dev_put(dev: pci_dev);
503}
504
505static void pci_device_shutdown(struct device *dev)
506{
507 struct pci_dev *pci_dev = to_pci_dev(dev);
508 struct pci_driver *drv = pci_dev->driver;
509
510 pm_runtime_resume(dev);
511
512 if (drv && drv->shutdown)
513 drv->shutdown(pci_dev);
514
515 /*
516 * If this is a kexec reboot, turn off Bus Master bit on the
517 * device to tell it to not continue to do DMA. Don't touch
518 * devices in D3cold or unknown states.
519 * If it is not a kexec reboot, firmware will hit the PCI
520 * devices with big hammer and stop their DMA any way.
521 */
522 if (kexec_in_progress && (pci_dev->current_state <= PCI_D3hot))
523 pci_clear_master(dev: pci_dev);
524}
525
526#ifdef CONFIG_PM_SLEEP
527
528/* Auxiliary functions used for system resume */
529
530/**
531 * pci_restore_standard_config - restore standard config registers of PCI device
532 * @pci_dev: PCI device to handle
533 */
534static int pci_restore_standard_config(struct pci_dev *pci_dev)
535{
536 pci_update_current_state(dev: pci_dev, PCI_UNKNOWN);
537
538 if (pci_dev->current_state != PCI_D0) {
539 int error = pci_set_power_state(dev: pci_dev, PCI_D0);
540 if (error)
541 return error;
542 }
543
544 pci_restore_state(dev: pci_dev);
545 pci_pme_restore(dev: pci_dev);
546 return 0;
547}
548#endif /* CONFIG_PM_SLEEP */
549
550#ifdef CONFIG_PM
551
552/* Auxiliary functions used for system resume and run-time resume */
553
554static void pci_pm_default_resume(struct pci_dev *pci_dev)
555{
556 pci_fixup_device(pass: pci_fixup_resume, dev: pci_dev);
557 pci_enable_wake(dev: pci_dev, PCI_D0, enable: false);
558}
559
560static void pci_pm_power_up_and_verify_state(struct pci_dev *pci_dev)
561{
562 pci_power_up(dev: pci_dev);
563 pci_update_current_state(dev: pci_dev, PCI_D0);
564}
565
566static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
567{
568 pci_pm_power_up_and_verify_state(pci_dev);
569 pci_restore_state(dev: pci_dev);
570 pci_pme_restore(dev: pci_dev);
571}
572
573static void pci_pm_bridge_power_up_actions(struct pci_dev *pci_dev)
574{
575 int ret;
576
577 ret = pci_bridge_wait_for_secondary_bus(dev: pci_dev, reset_type: "resume");
578 if (ret) {
579 /*
580 * The downstream link failed to come up, so mark the
581 * devices below as disconnected to make sure we don't
582 * attempt to resume them.
583 */
584 pci_walk_bus(top: pci_dev->subordinate, cb: pci_dev_set_disconnected,
585 NULL);
586 return;
587 }
588
589 /*
590 * When powering on a bridge from D3cold, the whole hierarchy may be
591 * powered on into D0uninitialized state, resume them to give them a
592 * chance to suspend again
593 */
594 pci_resume_bus(bus: pci_dev->subordinate);
595}
596
597#endif /* CONFIG_PM */
598
599#ifdef CONFIG_PM_SLEEP
600
601/*
602 * Default "suspend" method for devices that have no driver provided suspend,
603 * or not even a driver at all (second part).
604 */
605static void pci_pm_set_unknown_state(struct pci_dev *pci_dev)
606{
607 /*
608 * mark its power state as "unknown", since we don't know if
609 * e.g. the BIOS will change its device state when we suspend.
610 */
611 if (pci_dev->current_state == PCI_D0)
612 pci_dev->current_state = PCI_UNKNOWN;
613}
614
615/*
616 * Default "resume" method for devices that have no driver provided resume,
617 * or not even a driver at all (second part).
618 */
619static int pci_pm_reenable_device(struct pci_dev *pci_dev)
620{
621 int retval;
622
623 /* if the device was enabled before suspend, re-enable */
624 retval = pci_reenable_device(pci_dev);
625 /*
626 * if the device was busmaster before the suspend, make it busmaster
627 * again
628 */
629 if (pci_dev->is_busmaster)
630 pci_set_master(dev: pci_dev);
631
632 return retval;
633}
634
635static int pci_legacy_suspend(struct device *dev, pm_message_t state)
636{
637 struct pci_dev *pci_dev = to_pci_dev(dev);
638 struct pci_driver *drv = pci_dev->driver;
639
640 if (drv && drv->suspend) {
641 pci_power_t prev = pci_dev->current_state;
642 int error;
643
644 error = drv->suspend(pci_dev, state);
645 suspend_report_result(dev, drv->suspend, error);
646 if (error)
647 return error;
648
649 if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
650 && pci_dev->current_state != PCI_UNKNOWN) {
651 pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
652 "PCI PM: Device state not saved by %pS\n",
653 drv->suspend);
654 }
655 }
656
657 pci_fixup_device(pass: pci_fixup_suspend, dev: pci_dev);
658
659 return 0;
660}
661
662static int pci_legacy_suspend_late(struct device *dev)
663{
664 struct pci_dev *pci_dev = to_pci_dev(dev);
665
666 if (!pci_dev->state_saved)
667 pci_save_state(dev: pci_dev);
668
669 pci_pm_set_unknown_state(pci_dev);
670
671 pci_fixup_device(pass: pci_fixup_suspend_late, dev: pci_dev);
672
673 return 0;
674}
675
676static int pci_legacy_resume(struct device *dev)
677{
678 struct pci_dev *pci_dev = to_pci_dev(dev);
679 struct pci_driver *drv = pci_dev->driver;
680
681 pci_fixup_device(pass: pci_fixup_resume, dev: pci_dev);
682
683 return drv && drv->resume ?
684 drv->resume(pci_dev) : pci_pm_reenable_device(pci_dev);
685}
686
687/* Auxiliary functions used by the new power management framework */
688
689static void pci_pm_default_suspend(struct pci_dev *pci_dev)
690{
691 /* Disable non-bridge devices without PM support */
692 if (!pci_has_subordinate(pci_dev))
693 pci_disable_enabled_device(dev: pci_dev);
694}
695
696static bool pci_has_legacy_pm_support(struct pci_dev *pci_dev)
697{
698 struct pci_driver *drv = pci_dev->driver;
699 bool ret = drv && (drv->suspend || drv->resume);
700
701 /*
702 * Legacy PM support is used by default, so warn if the new framework is
703 * supported as well. Drivers are supposed to support either the
704 * former, or the latter, but not both at the same time.
705 */
706 pci_WARN(pci_dev, ret && drv->driver.pm, "device %04x:%04x\n",
707 pci_dev->vendor, pci_dev->device);
708
709 return ret;
710}
711
712/* New power management framework */
713
714static int pci_pm_prepare(struct device *dev)
715{
716 struct pci_dev *pci_dev = to_pci_dev(dev);
717 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
718
719 if (pm && pm->prepare) {
720 int error = pm->prepare(dev);
721 if (error < 0)
722 return error;
723
724 if (!error && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
725 return 0;
726 }
727 if (pci_dev_need_resume(dev: pci_dev))
728 return 0;
729
730 /*
731 * The PME setting needs to be adjusted here in case the direct-complete
732 * optimization is used with respect to this device.
733 */
734 pci_dev_adjust_pme(dev: pci_dev);
735 return 1;
736}
737
738static void pci_pm_complete(struct device *dev)
739{
740 struct pci_dev *pci_dev = to_pci_dev(dev);
741
742 pci_dev_complete_resume(pci_dev);
743 pm_generic_complete(dev);
744
745 /* Resume device if platform firmware has put it in reset-power-on */
746 if (pm_runtime_suspended(dev) && pm_resume_via_firmware()) {
747 pci_power_t pre_sleep_state = pci_dev->current_state;
748
749 pci_refresh_power_state(dev: pci_dev);
750 /*
751 * On platforms with ACPI this check may also trigger for
752 * devices sharing power resources if one of those power
753 * resources has been activated as a result of a change of the
754 * power state of another device sharing it. However, in that
755 * case it is also better to resume the device, in general.
756 */
757 if (pci_dev->current_state < pre_sleep_state)
758 pm_request_resume(dev);
759 }
760}
761
762#else /* !CONFIG_PM_SLEEP */
763
764#define pci_pm_prepare NULL
765#define pci_pm_complete NULL
766
767#endif /* !CONFIG_PM_SLEEP */
768
769#ifdef CONFIG_SUSPEND
770static void pcie_pme_root_status_cleanup(struct pci_dev *pci_dev)
771{
772 /*
773 * Some BIOSes forget to clear Root PME Status bits after system
774 * wakeup, which breaks ACPI-based runtime wakeup on PCI Express.
775 * Clear those bits now just in case (shouldn't hurt).
776 */
777 if (pci_is_pcie(dev: pci_dev) &&
778 (pci_pcie_type(dev: pci_dev) == PCI_EXP_TYPE_ROOT_PORT ||
779 pci_pcie_type(dev: pci_dev) == PCI_EXP_TYPE_RC_EC))
780 pcie_clear_root_pme_status(dev: pci_dev);
781}
782
783static int pci_pm_suspend(struct device *dev)
784{
785 struct pci_dev *pci_dev = to_pci_dev(dev);
786 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
787
788 pci_dev->skip_bus_pm = false;
789
790 /*
791 * Disabling PTM allows some systems, e.g., Intel mobile chips
792 * since Coffee Lake, to enter a lower-power PM state.
793 */
794 pci_suspend_ptm(dev: pci_dev);
795
796 if (pci_has_legacy_pm_support(pci_dev))
797 return pci_legacy_suspend(dev, PMSG_SUSPEND);
798
799 if (!pm) {
800 pci_pm_default_suspend(pci_dev);
801 return 0;
802 }
803
804 /*
805 * PCI devices suspended at run time may need to be resumed at this
806 * point, because in general it may be necessary to reconfigure them for
807 * system suspend. Namely, if the device is expected to wake up the
808 * system from the sleep state, it may have to be reconfigured for this
809 * purpose, or if the device is not expected to wake up the system from
810 * the sleep state, it should be prevented from signaling wakeup events
811 * going forward.
812 *
813 * Also if the driver of the device does not indicate that its system
814 * suspend callbacks can cope with runtime-suspended devices, it is
815 * better to resume the device from runtime suspend here.
816 */
817 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
818 pci_dev_need_resume(dev: pci_dev)) {
819 pm_runtime_resume(dev);
820 pci_dev->state_saved = false;
821 } else {
822 pci_dev_adjust_pme(dev: pci_dev);
823 }
824
825 if (pm->suspend) {
826 pci_power_t prev = pci_dev->current_state;
827 int error;
828
829 error = pm->suspend(dev);
830 suspend_report_result(dev, pm->suspend, error);
831 if (error)
832 return error;
833
834 if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
835 && pci_dev->current_state != PCI_UNKNOWN) {
836 pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
837 "PCI PM: State of device not saved by %pS\n",
838 pm->suspend);
839 }
840 }
841
842 return 0;
843}
844
845static int pci_pm_suspend_late(struct device *dev)
846{
847 if (dev_pm_skip_suspend(dev))
848 return 0;
849
850 pci_fixup_device(pass: pci_fixup_suspend, to_pci_dev(dev));
851
852 return pm_generic_suspend_late(dev);
853}
854
855static int pci_pm_suspend_noirq(struct device *dev)
856{
857 struct pci_dev *pci_dev = to_pci_dev(dev);
858 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
859
860 if (dev_pm_skip_suspend(dev))
861 return 0;
862
863 if (pci_has_legacy_pm_support(pci_dev))
864 return pci_legacy_suspend_late(dev);
865
866 if (!pm) {
867 pci_save_state(dev: pci_dev);
868 goto Fixup;
869 }
870
871 if (pm->suspend_noirq) {
872 pci_power_t prev = pci_dev->current_state;
873 int error;
874
875 error = pm->suspend_noirq(dev);
876 suspend_report_result(dev, pm->suspend_noirq, error);
877 if (error)
878 return error;
879
880 if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
881 && pci_dev->current_state != PCI_UNKNOWN) {
882 pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
883 "PCI PM: State of device not saved by %pS\n",
884 pm->suspend_noirq);
885 goto Fixup;
886 }
887 }
888
889 if (!pci_dev->state_saved) {
890 pci_save_state(dev: pci_dev);
891
892 /*
893 * If the device is a bridge with a child in D0 below it,
894 * it needs to stay in D0, so check skip_bus_pm to avoid
895 * putting it into a low-power state in that case.
896 */
897 if (!pci_dev->skip_bus_pm && pci_power_manageable(pci_dev))
898 pci_prepare_to_sleep(dev: pci_dev);
899 }
900
901 pci_dbg(pci_dev, "PCI PM: Suspend power state: %s\n",
902 pci_power_name(pci_dev->current_state));
903
904 if (pci_dev->current_state == PCI_D0) {
905 pci_dev->skip_bus_pm = true;
906 /*
907 * Per PCI PM r1.2, table 6-1, a bridge must be in D0 if any
908 * downstream device is in D0, so avoid changing the power state
909 * of the parent bridge by setting the skip_bus_pm flag for it.
910 */
911 if (pci_dev->bus->self)
912 pci_dev->bus->self->skip_bus_pm = true;
913 }
914
915 if (pci_dev->skip_bus_pm && pm_suspend_no_platform()) {
916 pci_dbg(pci_dev, "PCI PM: Skipped\n");
917 goto Fixup;
918 }
919
920 pci_pm_set_unknown_state(pci_dev);
921
922 /*
923 * Some BIOSes from ASUS have a bug: If a USB EHCI host controller's
924 * PCI COMMAND register isn't 0, the BIOS assumes that the controller
925 * hasn't been quiesced and tries to turn it off. If the controller
926 * is already in D3, this can hang or cause memory corruption.
927 *
928 * Since the value of the COMMAND register doesn't matter once the
929 * device has been suspended, we can safely set it to 0 here.
930 */
931 if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
932 pci_write_config_word(dev: pci_dev, PCI_COMMAND, val: 0);
933
934Fixup:
935 pci_fixup_device(pass: pci_fixup_suspend_late, dev: pci_dev);
936
937 /*
938 * If the target system sleep state is suspend-to-idle, it is sufficient
939 * to check whether or not the device's wakeup settings are good for
940 * runtime PM. Otherwise, the pm_resume_via_firmware() check will cause
941 * pci_pm_complete() to take care of fixing up the device's state
942 * anyway, if need be.
943 */
944 if (device_can_wakeup(dev) && !device_may_wakeup(dev))
945 dev->power.may_skip_resume = false;
946
947 return 0;
948}
949
950static int pci_pm_resume_noirq(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 pci_power_t prev_state = pci_dev->current_state;
955 bool skip_bus_pm = pci_dev->skip_bus_pm;
956
957 if (dev_pm_skip_resume(dev))
958 return 0;
959
960 /*
961 * In the suspend-to-idle case, devices left in D0 during suspend will
962 * stay in D0, so it is not necessary to restore or update their
963 * configuration here and attempting to put them into D0 again is
964 * pointless, so avoid doing that.
965 */
966 if (!(skip_bus_pm && pm_suspend_no_platform()))
967 pci_pm_default_resume_early(pci_dev);
968
969 pci_fixup_device(pass: pci_fixup_resume_early, dev: pci_dev);
970 pcie_pme_root_status_cleanup(pci_dev);
971
972 if (!skip_bus_pm && prev_state == PCI_D3cold)
973 pci_pm_bridge_power_up_actions(pci_dev);
974
975 if (pci_has_legacy_pm_support(pci_dev))
976 return 0;
977
978 if (pm && pm->resume_noirq)
979 return pm->resume_noirq(dev);
980
981 return 0;
982}
983
984static int pci_pm_resume_early(struct device *dev)
985{
986 if (dev_pm_skip_resume(dev))
987 return 0;
988
989 return pm_generic_resume_early(dev);
990}
991
992static int pci_pm_resume(struct device *dev)
993{
994 struct pci_dev *pci_dev = to_pci_dev(dev);
995 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
996
997 /*
998 * This is necessary for the suspend error path in which resume is
999 * called without restoring the standard config registers of the device.
1000 */
1001 if (pci_dev->state_saved)
1002 pci_restore_standard_config(pci_dev);
1003
1004 pci_resume_ptm(dev: pci_dev);
1005
1006 if (pci_has_legacy_pm_support(pci_dev))
1007 return pci_legacy_resume(dev);
1008
1009 pci_pm_default_resume(pci_dev);
1010
1011 if (pm) {
1012 if (pm->resume)
1013 return pm->resume(dev);
1014 } else {
1015 pci_pm_reenable_device(pci_dev);
1016 }
1017
1018 return 0;
1019}
1020
1021#else /* !CONFIG_SUSPEND */
1022
1023#define pci_pm_suspend NULL
1024#define pci_pm_suspend_late NULL
1025#define pci_pm_suspend_noirq NULL
1026#define pci_pm_resume NULL
1027#define pci_pm_resume_early NULL
1028#define pci_pm_resume_noirq NULL
1029
1030#endif /* !CONFIG_SUSPEND */
1031
1032#ifdef CONFIG_HIBERNATE_CALLBACKS
1033
1034static int pci_pm_freeze(struct device *dev)
1035{
1036 struct pci_dev *pci_dev = to_pci_dev(dev);
1037 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1038
1039 if (pci_has_legacy_pm_support(pci_dev))
1040 return pci_legacy_suspend(dev, PMSG_FREEZE);
1041
1042 if (!pm) {
1043 pci_pm_default_suspend(pci_dev);
1044 return 0;
1045 }
1046
1047 /*
1048 * Resume all runtime-suspended devices before creating a snapshot
1049 * image of system memory, because the restore kernel generally cannot
1050 * be expected to always handle them consistently and they need to be
1051 * put into the runtime-active metastate during system resume anyway,
1052 * so it is better to ensure that the state saved in the image will be
1053 * always consistent with that.
1054 */
1055 pm_runtime_resume(dev);
1056 pci_dev->state_saved = false;
1057
1058 if (pm->freeze) {
1059 int error;
1060
1061 error = pm->freeze(dev);
1062 suspend_report_result(dev, pm->freeze, error);
1063 if (error)
1064 return error;
1065 }
1066
1067 return 0;
1068}
1069
1070static int pci_pm_freeze_noirq(struct device *dev)
1071{
1072 struct pci_dev *pci_dev = to_pci_dev(dev);
1073 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1074
1075 if (pci_has_legacy_pm_support(pci_dev))
1076 return pci_legacy_suspend_late(dev);
1077
1078 if (pm && pm->freeze_noirq) {
1079 int error;
1080
1081 error = pm->freeze_noirq(dev);
1082 suspend_report_result(dev, pm->freeze_noirq, error);
1083 if (error)
1084 return error;
1085 }
1086
1087 if (!pci_dev->state_saved)
1088 pci_save_state(dev: pci_dev);
1089
1090 pci_pm_set_unknown_state(pci_dev);
1091
1092 return 0;
1093}
1094
1095static int pci_pm_thaw_noirq(struct device *dev)
1096{
1097 struct pci_dev *pci_dev = to_pci_dev(dev);
1098 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1099
1100 /*
1101 * The pm->thaw_noirq() callback assumes the device has been
1102 * returned to D0 and its config state has been restored.
1103 *
1104 * In addition, pci_restore_state() restores MSI-X state in MMIO
1105 * space, which requires the device to be in D0, so return it to D0
1106 * in case the driver's "freeze" callbacks put it into a low-power
1107 * state.
1108 */
1109 pci_pm_power_up_and_verify_state(pci_dev);
1110 pci_restore_state(dev: pci_dev);
1111
1112 if (pci_has_legacy_pm_support(pci_dev))
1113 return 0;
1114
1115 if (pm && pm->thaw_noirq)
1116 return pm->thaw_noirq(dev);
1117
1118 return 0;
1119}
1120
1121static int pci_pm_thaw(struct device *dev)
1122{
1123 struct pci_dev *pci_dev = to_pci_dev(dev);
1124 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1125 int error = 0;
1126
1127 if (pci_has_legacy_pm_support(pci_dev))
1128 return pci_legacy_resume(dev);
1129
1130 if (pm) {
1131 if (pm->thaw)
1132 error = pm->thaw(dev);
1133 } else {
1134 pci_pm_reenable_device(pci_dev);
1135 }
1136
1137 pci_dev->state_saved = false;
1138
1139 return error;
1140}
1141
1142static int pci_pm_poweroff(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
1147 if (pci_has_legacy_pm_support(pci_dev))
1148 return pci_legacy_suspend(dev, PMSG_HIBERNATE);
1149
1150 if (!pm) {
1151 pci_pm_default_suspend(pci_dev);
1152 return 0;
1153 }
1154
1155 /* The reason to do that is the same as in pci_pm_suspend(). */
1156 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
1157 pci_dev_need_resume(dev: pci_dev)) {
1158 pm_runtime_resume(dev);
1159 pci_dev->state_saved = false;
1160 } else {
1161 pci_dev_adjust_pme(dev: pci_dev);
1162 }
1163
1164 if (pm->poweroff) {
1165 int error;
1166
1167 error = pm->poweroff(dev);
1168 suspend_report_result(dev, pm->poweroff, error);
1169 if (error)
1170 return error;
1171 }
1172
1173 return 0;
1174}
1175
1176static int pci_pm_poweroff_late(struct device *dev)
1177{
1178 if (dev_pm_skip_suspend(dev))
1179 return 0;
1180
1181 pci_fixup_device(pass: pci_fixup_suspend, to_pci_dev(dev));
1182
1183 return pm_generic_poweroff_late(dev);
1184}
1185
1186static int pci_pm_poweroff_noirq(struct device *dev)
1187{
1188 struct pci_dev *pci_dev = to_pci_dev(dev);
1189 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1190
1191 if (dev_pm_skip_suspend(dev))
1192 return 0;
1193
1194 if (pci_has_legacy_pm_support(pci_dev))
1195 return pci_legacy_suspend_late(dev);
1196
1197 if (!pm) {
1198 pci_fixup_device(pass: pci_fixup_suspend_late, dev: pci_dev);
1199 return 0;
1200 }
1201
1202 if (pm->poweroff_noirq) {
1203 int error;
1204
1205 error = pm->poweroff_noirq(dev);
1206 suspend_report_result(dev, pm->poweroff_noirq, error);
1207 if (error)
1208 return error;
1209 }
1210
1211 if (!pci_dev->state_saved && !pci_has_subordinate(pci_dev))
1212 pci_prepare_to_sleep(dev: pci_dev);
1213
1214 /*
1215 * The reason for doing this here is the same as for the analogous code
1216 * in pci_pm_suspend_noirq().
1217 */
1218 if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
1219 pci_write_config_word(dev: pci_dev, PCI_COMMAND, val: 0);
1220
1221 pci_fixup_device(pass: pci_fixup_suspend_late, dev: pci_dev);
1222
1223 return 0;
1224}
1225
1226static int pci_pm_restore_noirq(struct device *dev)
1227{
1228 struct pci_dev *pci_dev = to_pci_dev(dev);
1229 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1230
1231 pci_pm_default_resume_early(pci_dev);
1232 pci_fixup_device(pass: pci_fixup_resume_early, dev: pci_dev);
1233
1234 if (pci_has_legacy_pm_support(pci_dev))
1235 return 0;
1236
1237 if (pm && pm->restore_noirq)
1238 return pm->restore_noirq(dev);
1239
1240 return 0;
1241}
1242
1243static int pci_pm_restore(struct device *dev)
1244{
1245 struct pci_dev *pci_dev = to_pci_dev(dev);
1246 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1247
1248 /*
1249 * This is necessary for the hibernation error path in which restore is
1250 * called without restoring the standard config registers of the device.
1251 */
1252 if (pci_dev->state_saved)
1253 pci_restore_standard_config(pci_dev);
1254
1255 if (pci_has_legacy_pm_support(pci_dev))
1256 return pci_legacy_resume(dev);
1257
1258 pci_pm_default_resume(pci_dev);
1259
1260 if (pm) {
1261 if (pm->restore)
1262 return pm->restore(dev);
1263 } else {
1264 pci_pm_reenable_device(pci_dev);
1265 }
1266
1267 return 0;
1268}
1269
1270#else /* !CONFIG_HIBERNATE_CALLBACKS */
1271
1272#define pci_pm_freeze NULL
1273#define pci_pm_freeze_noirq NULL
1274#define pci_pm_thaw NULL
1275#define pci_pm_thaw_noirq NULL
1276#define pci_pm_poweroff NULL
1277#define pci_pm_poweroff_late NULL
1278#define pci_pm_poweroff_noirq NULL
1279#define pci_pm_restore NULL
1280#define pci_pm_restore_noirq NULL
1281
1282#endif /* !CONFIG_HIBERNATE_CALLBACKS */
1283
1284#ifdef CONFIG_PM
1285
1286static int pci_pm_runtime_suspend(struct device *dev)
1287{
1288 struct pci_dev *pci_dev = to_pci_dev(dev);
1289 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1290 pci_power_t prev = pci_dev->current_state;
1291 int error;
1292
1293 pci_suspend_ptm(dev: pci_dev);
1294
1295 /*
1296 * If pci_dev->driver is not set (unbound), we leave the device in D0,
1297 * but it may go to D3cold when the bridge above it runtime suspends.
1298 * Save its config space in case that happens.
1299 */
1300 if (!pci_dev->driver) {
1301 pci_save_state(dev: pci_dev);
1302 return 0;
1303 }
1304
1305 pci_dev->state_saved = false;
1306 if (pm && pm->runtime_suspend) {
1307 error = pm->runtime_suspend(dev);
1308 /*
1309 * -EBUSY and -EAGAIN is used to request the runtime PM core
1310 * to schedule a new suspend, so log the event only with debug
1311 * log level.
1312 */
1313 if (error == -EBUSY || error == -EAGAIN) {
1314 pci_dbg(pci_dev, "can't suspend now (%ps returned %d)\n",
1315 pm->runtime_suspend, error);
1316 return error;
1317 } else if (error) {
1318 pci_err(pci_dev, "can't suspend (%ps returned %d)\n",
1319 pm->runtime_suspend, error);
1320 return error;
1321 }
1322 }
1323
1324 pci_fixup_device(pass: pci_fixup_suspend, dev: pci_dev);
1325
1326 if (pm && pm->runtime_suspend
1327 && !pci_dev->state_saved && pci_dev->current_state != PCI_D0
1328 && pci_dev->current_state != PCI_UNKNOWN) {
1329 pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
1330 "PCI PM: State of device not saved by %pS\n",
1331 pm->runtime_suspend);
1332 return 0;
1333 }
1334
1335 if (!pci_dev->state_saved) {
1336 pci_save_state(dev: pci_dev);
1337 pci_finish_runtime_suspend(dev: pci_dev);
1338 }
1339
1340 return 0;
1341}
1342
1343static int pci_pm_runtime_resume(struct device *dev)
1344{
1345 struct pci_dev *pci_dev = to_pci_dev(dev);
1346 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1347 pci_power_t prev_state = pci_dev->current_state;
1348 int error = 0;
1349
1350 /*
1351 * Restoring config space is necessary even if the device is not bound
1352 * to a driver because although we left it in D0, it may have gone to
1353 * D3cold when the bridge above it runtime suspended.
1354 */
1355 pci_pm_default_resume_early(pci_dev);
1356 pci_resume_ptm(dev: pci_dev);
1357
1358 if (!pci_dev->driver)
1359 return 0;
1360
1361 pci_fixup_device(pass: pci_fixup_resume_early, dev: pci_dev);
1362 pci_pm_default_resume(pci_dev);
1363
1364 if (prev_state == PCI_D3cold)
1365 pci_pm_bridge_power_up_actions(pci_dev);
1366
1367 if (pm && pm->runtime_resume)
1368 error = pm->runtime_resume(dev);
1369
1370 return error;
1371}
1372
1373static int pci_pm_runtime_idle(struct device *dev)
1374{
1375 struct pci_dev *pci_dev = to_pci_dev(dev);
1376 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1377
1378 /*
1379 * If pci_dev->driver is not set (unbound), the device should
1380 * always remain in D0 regardless of the runtime PM status
1381 */
1382 if (!pci_dev->driver)
1383 return 0;
1384
1385 if (!pm)
1386 return -ENOSYS;
1387
1388 if (pm->runtime_idle)
1389 return pm->runtime_idle(dev);
1390
1391 return 0;
1392}
1393
1394static const struct dev_pm_ops pci_dev_pm_ops = {
1395 .prepare = pci_pm_prepare,
1396 .complete = pci_pm_complete,
1397 .suspend = pci_pm_suspend,
1398 .suspend_late = pci_pm_suspend_late,
1399 .resume = pci_pm_resume,
1400 .resume_early = pci_pm_resume_early,
1401 .freeze = pci_pm_freeze,
1402 .thaw = pci_pm_thaw,
1403 .poweroff = pci_pm_poweroff,
1404 .poweroff_late = pci_pm_poweroff_late,
1405 .restore = pci_pm_restore,
1406 .suspend_noirq = pci_pm_suspend_noirq,
1407 .resume_noirq = pci_pm_resume_noirq,
1408 .freeze_noirq = pci_pm_freeze_noirq,
1409 .thaw_noirq = pci_pm_thaw_noirq,
1410 .poweroff_noirq = pci_pm_poweroff_noirq,
1411 .restore_noirq = pci_pm_restore_noirq,
1412 .runtime_suspend = pci_pm_runtime_suspend,
1413 .runtime_resume = pci_pm_runtime_resume,
1414 .runtime_idle = pci_pm_runtime_idle,
1415};
1416
1417#define PCI_PM_OPS_PTR (&pci_dev_pm_ops)
1418
1419#else /* !CONFIG_PM */
1420
1421#define pci_pm_runtime_suspend NULL
1422#define pci_pm_runtime_resume NULL
1423#define pci_pm_runtime_idle NULL
1424
1425#define PCI_PM_OPS_PTR NULL
1426
1427#endif /* !CONFIG_PM */
1428
1429/**
1430 * __pci_register_driver - register a new pci driver
1431 * @drv: the driver structure to register
1432 * @owner: owner module of drv
1433 * @mod_name: module name string
1434 *
1435 * Adds the driver structure to the list of registered drivers.
1436 * Returns a negative value on error, otherwise 0.
1437 * If no error occurred, the driver remains registered even if
1438 * no device was claimed during registration.
1439 */
1440int __pci_register_driver(struct pci_driver *drv, struct module *owner,
1441 const char *mod_name)
1442{
1443 /* initialize common driver fields */
1444 drv->driver.name = drv->name;
1445 drv->driver.bus = &pci_bus_type;
1446 drv->driver.owner = owner;
1447 drv->driver.mod_name = mod_name;
1448 drv->driver.groups = drv->groups;
1449 drv->driver.dev_groups = drv->dev_groups;
1450
1451 spin_lock_init(&drv->dynids.lock);
1452 INIT_LIST_HEAD(list: &drv->dynids.list);
1453
1454 /* register with core */
1455 return driver_register(drv: &drv->driver);
1456}
1457EXPORT_SYMBOL(__pci_register_driver);
1458
1459/**
1460 * pci_unregister_driver - unregister a pci driver
1461 * @drv: the driver structure to unregister
1462 *
1463 * Deletes the driver structure from the list of registered PCI drivers,
1464 * gives it a chance to clean up by calling its remove() function for
1465 * each device it was responsible for, and marks those devices as
1466 * driverless.
1467 */
1468
1469void pci_unregister_driver(struct pci_driver *drv)
1470{
1471 driver_unregister(drv: &drv->driver);
1472 pci_free_dynids(drv);
1473}
1474EXPORT_SYMBOL(pci_unregister_driver);
1475
1476static struct pci_driver pci_compat_driver = {
1477 .name = "compat"
1478};
1479
1480/**
1481 * pci_dev_driver - get the pci_driver of a device
1482 * @dev: the device to query
1483 *
1484 * Returns the appropriate pci_driver structure or %NULL if there is no
1485 * registered driver for the device.
1486 */
1487struct pci_driver *pci_dev_driver(const struct pci_dev *dev)
1488{
1489 int i;
1490
1491 if (dev->driver)
1492 return dev->driver;
1493
1494 for (i = 0; i <= PCI_ROM_RESOURCE; i++)
1495 if (dev->resource[i].flags & IORESOURCE_BUSY)
1496 return &pci_compat_driver;
1497
1498 return NULL;
1499}
1500EXPORT_SYMBOL(pci_dev_driver);
1501
1502/**
1503 * pci_bus_match - Tell if a PCI device structure has a matching PCI device id structure
1504 * @dev: the PCI device structure to match against
1505 * @drv: the device driver to search for matching PCI device id structures
1506 *
1507 * Used by a driver to check whether a PCI device present in the
1508 * system is in its list of supported devices. Returns the matching
1509 * pci_device_id structure or %NULL if there is no match.
1510 */
1511static int pci_bus_match(struct device *dev, struct device_driver *drv)
1512{
1513 struct pci_dev *pci_dev = to_pci_dev(dev);
1514 struct pci_driver *pci_drv;
1515 const struct pci_device_id *found_id;
1516
1517 if (!pci_dev->match_driver)
1518 return 0;
1519
1520 pci_drv = to_pci_driver(drv);
1521 found_id = pci_match_device(drv: pci_drv, dev: pci_dev);
1522 if (found_id)
1523 return 1;
1524
1525 return 0;
1526}
1527
1528/**
1529 * pci_dev_get - increments the reference count of the pci device structure
1530 * @dev: the device being referenced
1531 *
1532 * Each live reference to a device should be refcounted.
1533 *
1534 * Drivers for PCI devices should normally record such references in
1535 * their probe() methods, when they bind to a device, and release
1536 * them by calling pci_dev_put(), in their disconnect() methods.
1537 *
1538 * A pointer to the device with the incremented reference counter is returned.
1539 */
1540struct pci_dev *pci_dev_get(struct pci_dev *dev)
1541{
1542 if (dev)
1543 get_device(dev: &dev->dev);
1544 return dev;
1545}
1546EXPORT_SYMBOL(pci_dev_get);
1547
1548/**
1549 * pci_dev_put - release a use of the pci device structure
1550 * @dev: device that's been disconnected
1551 *
1552 * Must be called when a user of a device is finished with it. When the last
1553 * user of the device calls this function, the memory of the device is freed.
1554 */
1555void pci_dev_put(struct pci_dev *dev)
1556{
1557 if (dev)
1558 put_device(dev: &dev->dev);
1559}
1560EXPORT_SYMBOL(pci_dev_put);
1561
1562static int pci_uevent(const struct device *dev, struct kobj_uevent_env *env)
1563{
1564 const struct pci_dev *pdev;
1565
1566 if (!dev)
1567 return -ENODEV;
1568
1569 pdev = to_pci_dev(dev);
1570
1571 if (add_uevent_var(env, format: "PCI_CLASS=%04X", pdev->class))
1572 return -ENOMEM;
1573
1574 if (add_uevent_var(env, format: "PCI_ID=%04X:%04X", pdev->vendor, pdev->device))
1575 return -ENOMEM;
1576
1577 if (add_uevent_var(env, format: "PCI_SUBSYS_ID=%04X:%04X", pdev->subsystem_vendor,
1578 pdev->subsystem_device))
1579 return -ENOMEM;
1580
1581 if (add_uevent_var(env, format: "PCI_SLOT_NAME=%s", pci_name(pdev)))
1582 return -ENOMEM;
1583
1584 if (add_uevent_var(env, format: "MODALIAS=pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02X",
1585 pdev->vendor, pdev->device,
1586 pdev->subsystem_vendor, pdev->subsystem_device,
1587 (u8)(pdev->class >> 16), (u8)(pdev->class >> 8),
1588 (u8)(pdev->class)))
1589 return -ENOMEM;
1590
1591 return 0;
1592}
1593
1594#if defined(CONFIG_PCIEAER) || defined(CONFIG_EEH)
1595/**
1596 * pci_uevent_ers - emit a uevent during recovery path of PCI device
1597 * @pdev: PCI device undergoing error recovery
1598 * @err_type: type of error event
1599 */
1600void pci_uevent_ers(struct pci_dev *pdev, enum pci_ers_result err_type)
1601{
1602 int idx = 0;
1603 char *envp[3];
1604
1605 switch (err_type) {
1606 case PCI_ERS_RESULT_NONE:
1607 case PCI_ERS_RESULT_CAN_RECOVER:
1608 envp[idx++] = "ERROR_EVENT=BEGIN_RECOVERY";
1609 envp[idx++] = "DEVICE_ONLINE=0";
1610 break;
1611 case PCI_ERS_RESULT_RECOVERED:
1612 envp[idx++] = "ERROR_EVENT=SUCCESSFUL_RECOVERY";
1613 envp[idx++] = "DEVICE_ONLINE=1";
1614 break;
1615 case PCI_ERS_RESULT_DISCONNECT:
1616 envp[idx++] = "ERROR_EVENT=FAILED_RECOVERY";
1617 envp[idx++] = "DEVICE_ONLINE=0";
1618 break;
1619 default:
1620 break;
1621 }
1622
1623 if (idx > 0) {
1624 envp[idx++] = NULL;
1625 kobject_uevent_env(kobj: &pdev->dev.kobj, action: KOBJ_CHANGE, envp);
1626 }
1627}
1628#endif
1629
1630static int pci_bus_num_vf(struct device *dev)
1631{
1632 return pci_num_vf(to_pci_dev(dev));
1633}
1634
1635/**
1636 * pci_dma_configure - Setup DMA configuration
1637 * @dev: ptr to dev structure
1638 *
1639 * Function to update PCI devices's DMA configuration using the same
1640 * info from the OF node or ACPI node of host bridge's parent (if any).
1641 */
1642static int pci_dma_configure(struct device *dev)
1643{
1644 struct pci_driver *driver = to_pci_driver(drv: dev->driver);
1645 struct device *bridge;
1646 int ret = 0;
1647
1648 bridge = pci_get_host_bridge_device(to_pci_dev(dev));
1649
1650 if (IS_ENABLED(CONFIG_OF) && bridge->parent &&
1651 bridge->parent->of_node) {
1652 ret = of_dma_configure(dev, np: bridge->parent->of_node, force_dma: true);
1653 } else if (has_acpi_companion(dev: bridge)) {
1654 struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);
1655
1656 ret = acpi_dma_configure(dev, attr: acpi_get_dma_attr(adev));
1657 }
1658
1659 pci_put_host_bridge_device(dev: bridge);
1660
1661 if (!ret && !driver->driver_managed_dma) {
1662 ret = iommu_device_use_default_domain(dev);
1663 if (ret)
1664 arch_teardown_dma_ops(dev);
1665 }
1666
1667 return ret;
1668}
1669
1670static void pci_dma_cleanup(struct device *dev)
1671{
1672 struct pci_driver *driver = to_pci_driver(drv: dev->driver);
1673
1674 if (!driver->driver_managed_dma)
1675 iommu_device_unuse_default_domain(dev);
1676}
1677
1678struct bus_type pci_bus_type = {
1679 .name = "pci",
1680 .match = pci_bus_match,
1681 .uevent = pci_uevent,
1682 .probe = pci_device_probe,
1683 .remove = pci_device_remove,
1684 .shutdown = pci_device_shutdown,
1685 .dev_groups = pci_dev_groups,
1686 .bus_groups = pci_bus_groups,
1687 .drv_groups = pci_drv_groups,
1688 .pm = PCI_PM_OPS_PTR,
1689 .num_vf = pci_bus_num_vf,
1690 .dma_configure = pci_dma_configure,
1691 .dma_cleanup = pci_dma_cleanup,
1692};
1693EXPORT_SYMBOL(pci_bus_type);
1694
1695#ifdef CONFIG_PCIEPORTBUS
1696static int pcie_port_bus_match(struct device *dev, struct device_driver *drv)
1697{
1698 struct pcie_device *pciedev;
1699 struct pcie_port_service_driver *driver;
1700
1701 if (drv->bus != &pcie_port_bus_type || dev->bus != &pcie_port_bus_type)
1702 return 0;
1703
1704 pciedev = to_pcie_device(dev);
1705 driver = to_service_driver(drv);
1706
1707 if (driver->service != pciedev->service)
1708 return 0;
1709
1710 if (driver->port_type != PCIE_ANY_PORT &&
1711 driver->port_type != pci_pcie_type(dev: pciedev->port))
1712 return 0;
1713
1714 return 1;
1715}
1716
1717struct bus_type pcie_port_bus_type = {
1718 .name = "pci_express",
1719 .match = pcie_port_bus_match,
1720};
1721#endif
1722
1723static int __init pci_driver_init(void)
1724{
1725 int ret;
1726
1727 ret = bus_register(bus: &pci_bus_type);
1728 if (ret)
1729 return ret;
1730
1731#ifdef CONFIG_PCIEPORTBUS
1732 ret = bus_register(bus: &pcie_port_bus_type);
1733 if (ret)
1734 return ret;
1735#endif
1736 dma_debug_add_bus(bus: &pci_bus_type);
1737 return 0;
1738}
1739postcore_initcall(pci_driver_init);
1740

source code of linux/drivers/pci/pci-driver.c