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1// SPDX-License-Identifier: GPL-2.02/*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 devices34 * @drv: target pci driver35 * @vendor: PCI vendor ID36 * @device: PCI device ID37 * @subvendor: PCI subvendor ID38 * @subdevice: PCI subdevice ID39 * @class: PCI class40 * @class_mask: PCI class mask41 * @driver_data: private driver data42 *43 * Adds a new dynamic pci device ID to this driver and causes the44 * driver to probe for all devices again.  @drv must have been45 * 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(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(&drv->dynids.lock);74	list_add_tail(&dynid->node, &drv->dynids.list);75	spin_unlock(&drv->dynids.lock);76 77	return driver_attach(&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(&drv->dynids.lock);86	list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {87		list_del(&dynid->node);88		kfree(dynid);89	}90	spin_unlock(&drv->dynids.lock);91}92 93/**94 * pci_match_id - See if a PCI device matches a given pci_id table95 * @ids: array of PCI device ID structures to search in96 * @dev: the PCI device structure to match against.97 *98 * Used by a driver to check whether a PCI device is in its list of99 * supported devices.  Returns the matching pci_device_id structure or100 * %NULL if there is no match.101 *102 * Deprecated; don't use this as it will not catch any dynamic IDs103 * 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(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 IDs128 * @drv: the PCI driver to match against129 * @dev: the PCI device structure to match against130 *131 * Used by a driver to check whether a PCI device is in its list of132 * supported devices or in the dynids list, which may have been augmented133 * via the sysfs "new_id" file.  Returns the matching pci_device_id134 * 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(&drv->dynids.lock);148	list_for_each_entry(dynid, &drv->dynids.list, node) {149		if (pci_match_one_device(&dynid->id, dev)) {150			found_id = &dynid->id;151			break;152		}153	}154	spin_unlock(&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_override164		 * 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 driver183 * @buf: buffer for scanning device ID data184 * @count: input size185 *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(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(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(pdrv, pdev))217			retval = -EEXIST;218 219		kfree(pdev);220 221		if (retval)222			return retval;223	}224 225	/* Only accept driver_data values that match an existing id_table226	   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 driver250 * @driver: target device driver251 * @buf: buffer for scanning device ID data252 * @count: input size253 *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(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(&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(&dynid->node);281			kfree(dynid);282			retval = count;283			break;284		}285	}286	spin_unlock(&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 of315	 * runtime PM status.  During probe, the device is set to316	 * active and the usage count is incremented.  If the driver317	 * supports runtime PM, it should call pm_runtime_put_noidle(),318	 * or any other runtime PM helper function decrementing the usage319	 * count, in its probe routine and pm_runtime_get_noresume() in320	 * 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 success334	 * 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_IOV344	return dev->is_virtfn && dev->physfn->is_probed;345#else346	return false;347#endif348}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 is358	 * attached.  This way the driver likely allocates its local memory359	 * on the right node.360	 */361	node = dev_to_node(&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 Function368	 * 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(&wq_domain_mask, GFP_KERNEL)) {377			error = -ENOMEM;378			goto out;379		}380		cpumask_and(wq_domain_mask,381			    housekeeping_cpumask(HK_TYPE_WQ),382			    housekeeping_cpumask(HK_TYPE_DOMAIN));383 384		cpu = cpumask_any_and(cpumask_of_node(node),385				      wq_domain_mask);386		free_cpumask_var(wq_domain_mask);387	}388 389	if (cpu < nr_cpu_ids)390		error = work_on_cpu(cpu, local_pci_probe, &ddi);391	else392		error = local_pci_probe(&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 device401 * @drv: driver to call to check if it wants the PCI device402 * @pci_dev: PCI device being probed403 *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, pci_dev);416		if (id)417			error = pci_call_probe(drv, pci_dev, id);418	}419	return error;420}421 422#ifdef CONFIG_PCI_IOV423static inline bool pci_device_can_probe(struct pci_dev *pdev)424{425	return (!pdev->is_virtfn || pdev->physfn->sriov->drivers_autoprobe ||426		pdev->driver_override);427}428#else429static inline bool pci_device_can_probe(struct pci_dev *pdev)430{431	return true;432}433#endif434 435static int pci_device_probe(struct device *dev)436{437	int error;438	struct pci_dev *pci_dev = to_pci_dev(dev);439	struct pci_driver *drv = to_pci_driver(dev->driver);440 441	if (!pci_device_can_probe(pci_dev))442		return -ENODEV;443 444	pci_assign_irq(pci_dev);445 446	error = pcibios_alloc_irq(pci_dev);447	if (error < 0)448		return error;449 450	pci_dev_get(pci_dev);451	error = __pci_device_probe(drv, pci_dev);452	if (error) {453		pcibios_free_irq(pci_dev);454		pci_dev_put(pci_dev);455	}456 457	return error;458}459 460static void pci_device_remove(struct device *dev)461{462	struct pci_dev *pci_dev = to_pci_dev(dev);463	struct pci_driver *drv = pci_dev->driver;464 465	if (drv->remove) {466		pm_runtime_get_sync(dev);467		/*468		 * If the driver provides a .runtime_idle() callback and it has469		 * started to run already, it may continue to run in parallel470		 * with the code below, so wait until all of the runtime PM471		 * activity has completed.472		 */473		pm_runtime_barrier(dev);474		drv->remove(pci_dev);475		pm_runtime_put_noidle(dev);476	}477	pcibios_free_irq(pci_dev);478	pci_dev->driver = NULL;479	pci_iov_remove(pci_dev);480 481	/* Undo the runtime PM settings in local_pci_probe() */482	pm_runtime_put_sync(dev);483 484	/*485	 * If the device is still on, set the power state as "unknown",486	 * since it might change by the next time we load the driver.487	 */488	if (pci_dev->current_state == PCI_D0)489		pci_dev->current_state = PCI_UNKNOWN;490 491	/*492	 * We would love to complain here if pci_dev->is_enabled is set, that493	 * the driver should have called pci_disable_device(), but the494	 * unfortunate fact is there are too many odd BIOS and bridge setups495	 * that don't like drivers doing that all of the time.496	 * Oh well, we can dream of sane hardware when we sleep, no matter how497	 * horrible the crap we have to deal with is when we are awake...498	 */499 500	pci_dev_put(pci_dev);501}502 503static void pci_device_shutdown(struct device *dev)504{505	struct pci_dev *pci_dev = to_pci_dev(dev);506	struct pci_driver *drv = pci_dev->driver;507 508	pm_runtime_resume(dev);509 510	if (drv && drv->shutdown)511		drv->shutdown(pci_dev);512 513	/*514	 * If this is a kexec reboot, turn off Bus Master bit on the515	 * device to tell it to not continue to do DMA. Don't touch516	 * devices in D3cold or unknown states.517	 * If it is not a kexec reboot, firmware will hit the PCI518	 * devices with big hammer and stop their DMA any way.519	 */520	if (kexec_in_progress && (pci_dev->current_state <= PCI_D3hot))521		pci_clear_master(pci_dev);522}523 524#ifdef CONFIG_PM_SLEEP525 526/* Auxiliary functions used for system resume */527 528/**529 * pci_restore_standard_config - restore standard config registers of PCI device530 * @pci_dev: PCI device to handle531 */532static int pci_restore_standard_config(struct pci_dev *pci_dev)533{534	pci_update_current_state(pci_dev, PCI_UNKNOWN);535 536	if (pci_dev->current_state != PCI_D0) {537		int error = pci_set_power_state(pci_dev, PCI_D0);538		if (error)539			return error;540	}541 542	pci_restore_state(pci_dev);543	pci_pme_restore(pci_dev);544	return 0;545}546#endif /* CONFIG_PM_SLEEP */547 548#ifdef CONFIG_PM549 550/* Auxiliary functions used for system resume and run-time resume */551 552static void pci_pm_default_resume(struct pci_dev *pci_dev)553{554	pci_fixup_device(pci_fixup_resume, pci_dev);555	pci_enable_wake(pci_dev, PCI_D0, false);556}557 558static void pci_pm_power_up_and_verify_state(struct pci_dev *pci_dev)559{560	pci_power_up(pci_dev);561	pci_update_current_state(pci_dev, PCI_D0);562}563 564static void pci_pm_default_resume_early(struct pci_dev *pci_dev)565{566	pci_pm_power_up_and_verify_state(pci_dev);567	pci_restore_state(pci_dev);568	pci_pme_restore(pci_dev);569}570 571static void pci_pm_bridge_power_up_actions(struct pci_dev *pci_dev)572{573	int ret;574 575	ret = pci_bridge_wait_for_secondary_bus(pci_dev, "resume");576	if (ret) {577		/*578		 * The downstream link failed to come up, so mark the579		 * devices below as disconnected to make sure we don't580		 * attempt to resume them.581		 */582		pci_walk_bus(pci_dev->subordinate, pci_dev_set_disconnected,583			     NULL);584		return;585	}586 587	/*588	 * When powering on a bridge from D3cold, the whole hierarchy may be589	 * powered on into D0uninitialized state, resume them to give them a590	 * chance to suspend again591	 */592	pci_resume_bus(pci_dev->subordinate);593}594 595#endif /* CONFIG_PM */596 597#ifdef CONFIG_PM_SLEEP598 599/*600 * Default "suspend" method for devices that have no driver provided suspend,601 * or not even a driver at all (second part).602 */603static void pci_pm_set_unknown_state(struct pci_dev *pci_dev)604{605	/*606	 * mark its power state as "unknown", since we don't know if607	 * e.g. the BIOS will change its device state when we suspend.608	 */609	if (pci_dev->current_state == PCI_D0)610		pci_dev->current_state = PCI_UNKNOWN;611}612 613/*614 * Default "resume" method for devices that have no driver provided resume,615 * or not even a driver at all (second part).616 */617static int pci_pm_reenable_device(struct pci_dev *pci_dev)618{619	int retval;620 621	/* if the device was enabled before suspend, re-enable */622	retval = pci_reenable_device(pci_dev);623	/*624	 * if the device was busmaster before the suspend, make it busmaster625	 * again626	 */627	if (pci_dev->is_busmaster)628		pci_set_master(pci_dev);629 630	return retval;631}632 633static int pci_legacy_suspend(struct device *dev, pm_message_t state)634{635	struct pci_dev *pci_dev = to_pci_dev(dev);636	struct pci_driver *drv = pci_dev->driver;637 638	if (drv && drv->suspend) {639		pci_power_t prev = pci_dev->current_state;640		int error;641 642		error = drv->suspend(pci_dev, state);643		suspend_report_result(dev, drv->suspend, error);644		if (error)645			return error;646 647		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0648		    && pci_dev->current_state != PCI_UNKNOWN) {649			pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,650				      "PCI PM: Device state not saved by %pS\n",651				      drv->suspend);652		}653	}654 655	pci_fixup_device(pci_fixup_suspend, pci_dev);656 657	return 0;658}659 660static int pci_legacy_suspend_late(struct device *dev)661{662	struct pci_dev *pci_dev = to_pci_dev(dev);663 664	if (!pci_dev->state_saved)665		pci_save_state(pci_dev);666 667	pci_pm_set_unknown_state(pci_dev);668 669	pci_fixup_device(pci_fixup_suspend_late, pci_dev);670 671	return 0;672}673 674static int pci_legacy_resume(struct device *dev)675{676	struct pci_dev *pci_dev = to_pci_dev(dev);677	struct pci_driver *drv = pci_dev->driver;678 679	pci_fixup_device(pci_fixup_resume, pci_dev);680 681	return drv && drv->resume ?682			drv->resume(pci_dev) : pci_pm_reenable_device(pci_dev);683}684 685/* Auxiliary functions used by the new power management framework */686 687static void pci_pm_default_suspend(struct pci_dev *pci_dev)688{689	/* Disable non-bridge devices without PM support */690	if (!pci_has_subordinate(pci_dev))691		pci_disable_enabled_device(pci_dev);692}693 694static bool pci_has_legacy_pm_support(struct pci_dev *pci_dev)695{696	struct pci_driver *drv = pci_dev->driver;697	bool ret = drv && (drv->suspend || drv->resume);698 699	/*700	 * Legacy PM support is used by default, so warn if the new framework is701	 * supported as well.  Drivers are supposed to support either the702	 * former, or the latter, but not both at the same time.703	 */704	pci_WARN(pci_dev, ret && drv->driver.pm, "device %04x:%04x\n",705		 pci_dev->vendor, pci_dev->device);706 707	return ret;708}709 710/* New power management framework */711 712static int pci_pm_prepare(struct device *dev)713{714	struct pci_dev *pci_dev = to_pci_dev(dev);715	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;716 717	if (pm && pm->prepare) {718		int error = pm->prepare(dev);719		if (error < 0)720			return error;721 722		if (!error && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))723			return 0;724	}725	if (pci_dev_need_resume(pci_dev))726		return 0;727 728	/*729	 * The PME setting needs to be adjusted here in case the direct-complete730	 * optimization is used with respect to this device.731	 */732	pci_dev_adjust_pme(pci_dev);733	return 1;734}735 736static void pci_pm_complete(struct device *dev)737{738	struct pci_dev *pci_dev = to_pci_dev(dev);739 740	pci_dev_complete_resume(pci_dev);741	pm_generic_complete(dev);742 743	/* Resume device if platform firmware has put it in reset-power-on */744	if (pm_runtime_suspended(dev) && pm_resume_via_firmware()) {745		pci_power_t pre_sleep_state = pci_dev->current_state;746 747		pci_refresh_power_state(pci_dev);748		/*749		 * On platforms with ACPI this check may also trigger for750		 * devices sharing power resources if one of those power751		 * resources has been activated as a result of a change of the752		 * power state of another device sharing it.  However, in that753		 * case it is also better to resume the device, in general.754		 */755		if (pci_dev->current_state < pre_sleep_state)756			pm_request_resume(dev);757	}758}759 760#else /* !CONFIG_PM_SLEEP */761 762#define pci_pm_prepare	NULL763#define pci_pm_complete	NULL764 765#endif /* !CONFIG_PM_SLEEP */766 767#ifdef CONFIG_SUSPEND768static void pcie_pme_root_status_cleanup(struct pci_dev *pci_dev)769{770	/*771	 * Some BIOSes forget to clear Root PME Status bits after system772	 * wakeup, which breaks ACPI-based runtime wakeup on PCI Express.773	 * Clear those bits now just in case (shouldn't hurt).774	 */775	if (pci_is_pcie(pci_dev) &&776	    (pci_pcie_type(pci_dev) == PCI_EXP_TYPE_ROOT_PORT ||777	     pci_pcie_type(pci_dev) == PCI_EXP_TYPE_RC_EC))778		pcie_clear_root_pme_status(pci_dev);779}780 781static int pci_pm_suspend(struct device *dev)782{783	struct pci_dev *pci_dev = to_pci_dev(dev);784	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;785 786	pci_dev->skip_bus_pm = false;787 788	/*789	 * Disabling PTM allows some systems, e.g., Intel mobile chips790	 * since Coffee Lake, to enter a lower-power PM state.791	 */792	pci_suspend_ptm(pci_dev);793 794	if (pci_has_legacy_pm_support(pci_dev))795		return pci_legacy_suspend(dev, PMSG_SUSPEND);796 797	if (!pm) {798		pci_pm_default_suspend(pci_dev);799		return 0;800	}801 802	/*803	 * PCI devices suspended at run time may need to be resumed at this804	 * point, because in general it may be necessary to reconfigure them for805	 * system suspend.  Namely, if the device is expected to wake up the806	 * system from the sleep state, it may have to be reconfigured for this807	 * purpose, or if the device is not expected to wake up the system from808	 * the sleep state, it should be prevented from signaling wakeup events809	 * going forward.810	 *811	 * Also if the driver of the device does not indicate that its system812	 * suspend callbacks can cope with runtime-suspended devices, it is813	 * better to resume the device from runtime suspend here.814	 */815	if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||816	    pci_dev_need_resume(pci_dev)) {817		pm_runtime_resume(dev);818		pci_dev->state_saved = false;819	} else {820		pci_dev_adjust_pme(pci_dev);821	}822 823	if (pm->suspend) {824		pci_power_t prev = pci_dev->current_state;825		int error;826 827		error = pm->suspend(dev);828		suspend_report_result(dev, pm->suspend, error);829		if (error)830			return error;831 832		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0833		    && pci_dev->current_state != PCI_UNKNOWN) {834			pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,835				      "PCI PM: State of device not saved by %pS\n",836				      pm->suspend);837		}838	}839 840	return 0;841}842 843static int pci_pm_suspend_late(struct device *dev)844{845	if (dev_pm_skip_suspend(dev))846		return 0;847 848	pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev));849 850	return pm_generic_suspend_late(dev);851}852 853static int pci_pm_suspend_noirq(struct device *dev)854{855	struct pci_dev *pci_dev = to_pci_dev(dev);856	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;857 858	if (dev_pm_skip_suspend(dev))859		return 0;860 861	if (pci_has_legacy_pm_support(pci_dev))862		return pci_legacy_suspend_late(dev);863 864	if (!pm) {865		pci_save_state(pci_dev);866		goto Fixup;867	}868 869	if (pm->suspend_noirq) {870		pci_power_t prev = pci_dev->current_state;871		int error;872 873		error = pm->suspend_noirq(dev);874		suspend_report_result(dev, pm->suspend_noirq, error);875		if (error)876			return error;877 878		if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0879		    && pci_dev->current_state != PCI_UNKNOWN) {880			pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,881				      "PCI PM: State of device not saved by %pS\n",882				      pm->suspend_noirq);883			goto Fixup;884		}885	}886 887	if (!pci_dev->state_saved) {888		pci_save_state(pci_dev);889 890		/*891		 * If the device is a bridge with a child in D0 below it,892		 * it needs to stay in D0, so check skip_bus_pm to avoid893		 * putting it into a low-power state in that case.894		 */895		if (!pci_dev->skip_bus_pm && pci_power_manageable(pci_dev))896			pci_prepare_to_sleep(pci_dev);897	}898 899	pci_dbg(pci_dev, "PCI PM: Suspend power state: %s\n",900		pci_power_name(pci_dev->current_state));901 902	if (pci_dev->current_state == PCI_D0) {903		pci_dev->skip_bus_pm = true;904		/*905		 * Per PCI PM r1.2, table 6-1, a bridge must be in D0 if any906		 * downstream device is in D0, so avoid changing the power state907		 * of the parent bridge by setting the skip_bus_pm flag for it.908		 */909		if (pci_dev->bus->self)910			pci_dev->bus->self->skip_bus_pm = true;911	}912 913	if (pci_dev->skip_bus_pm && pm_suspend_no_platform()) {914		pci_dbg(pci_dev, "PCI PM: Skipped\n");915		goto Fixup;916	}917 918	pci_pm_set_unknown_state(pci_dev);919 920	/*921	 * Some BIOSes from ASUS have a bug: If a USB EHCI host controller's922	 * PCI COMMAND register isn't 0, the BIOS assumes that the controller923	 * hasn't been quiesced and tries to turn it off.  If the controller924	 * is already in D3, this can hang or cause memory corruption.925	 *926	 * Since the value of the COMMAND register doesn't matter once the927	 * device has been suspended, we can safely set it to 0 here.928	 */929	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)930		pci_write_config_word(pci_dev, PCI_COMMAND, 0);931 932Fixup:933	pci_fixup_device(pci_fixup_suspend_late, pci_dev);934 935	/*936	 * If the target system sleep state is suspend-to-idle, it is sufficient937	 * to check whether or not the device's wakeup settings are good for938	 * runtime PM.  Otherwise, the pm_resume_via_firmware() check will cause939	 * pci_pm_complete() to take care of fixing up the device's state940	 * anyway, if need be.941	 */942	if (device_can_wakeup(dev) && !device_may_wakeup(dev))943		dev->power.may_skip_resume = false;944 945	return 0;946}947 948static int pci_pm_resume_noirq(struct device *dev)949{950	struct pci_dev *pci_dev = to_pci_dev(dev);951	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;952	pci_power_t prev_state = pci_dev->current_state;953	bool skip_bus_pm = pci_dev->skip_bus_pm;954 955	if (dev_pm_skip_resume(dev))956		return 0;957 958	/*959	 * In the suspend-to-idle case, devices left in D0 during suspend will960	 * stay in D0, so it is not necessary to restore or update their961	 * configuration here and attempting to put them into D0 again is962	 * pointless, so avoid doing that.963	 */964	if (!(skip_bus_pm && pm_suspend_no_platform()))965		pci_pm_default_resume_early(pci_dev);966 967	pci_fixup_device(pci_fixup_resume_early, pci_dev);968	pcie_pme_root_status_cleanup(pci_dev);969 970	if (!skip_bus_pm && prev_state == PCI_D3cold)971		pci_pm_bridge_power_up_actions(pci_dev);972 973	if (pci_has_legacy_pm_support(pci_dev))974		return 0;975 976	if (pm && pm->resume_noirq)977		return pm->resume_noirq(dev);978 979	return 0;980}981 982static int pci_pm_resume_early(struct device *dev)983{984	if (dev_pm_skip_resume(dev))985		return 0;986 987	return pm_generic_resume_early(dev);988}989 990static int pci_pm_resume(struct device *dev)991{992	struct pci_dev *pci_dev = to_pci_dev(dev);993	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;994 995	/*996	 * This is necessary for the suspend error path in which resume is997	 * called without restoring the standard config registers of the device.998	 */999	if (pci_dev->state_saved)1000		pci_restore_standard_config(pci_dev);1001 1002	pci_resume_ptm(pci_dev);1003 1004	if (pci_has_legacy_pm_support(pci_dev))1005		return pci_legacy_resume(dev);1006 1007	pci_pm_default_resume(pci_dev);1008 1009	if (pm) {1010		if (pm->resume)1011			return pm->resume(dev);1012	} else {1013		pci_pm_reenable_device(pci_dev);1014	}1015 1016	return 0;1017}1018 1019#else /* !CONFIG_SUSPEND */1020 1021#define pci_pm_suspend		NULL1022#define pci_pm_suspend_late	NULL1023#define pci_pm_suspend_noirq	NULL1024#define pci_pm_resume		NULL1025#define pci_pm_resume_early	NULL1026#define pci_pm_resume_noirq	NULL1027 1028#endif /* !CONFIG_SUSPEND */1029 1030#ifdef CONFIG_HIBERNATE_CALLBACKS1031 1032static int pci_pm_freeze(struct device *dev)1033{1034	struct pci_dev *pci_dev = to_pci_dev(dev);1035	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;1036 1037	if (pci_has_legacy_pm_support(pci_dev))1038		return pci_legacy_suspend(dev, PMSG_FREEZE);1039 1040	if (!pm) {1041		pci_pm_default_suspend(pci_dev);1042		return 0;1043	}1044 1045	/*1046	 * Resume all runtime-suspended devices before creating a snapshot1047	 * image of system memory, because the restore kernel generally cannot1048	 * be expected to always handle them consistently and they need to be1049	 * put into the runtime-active metastate during system resume anyway,1050	 * so it is better to ensure that the state saved in the image will be1051	 * always consistent with that.1052	 */1053	pm_runtime_resume(dev);1054	pci_dev->state_saved = false;1055 1056	if (pm->freeze) {1057		int error;1058 1059		error = pm->freeze(dev);1060		suspend_report_result(dev, pm->freeze, error);1061		if (error)1062			return error;1063	}1064 1065	return 0;1066}1067 1068static int pci_pm_freeze_noirq(struct device *dev)1069{1070	struct pci_dev *pci_dev = to_pci_dev(dev);1071	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;1072 1073	if (pci_has_legacy_pm_support(pci_dev))1074		return pci_legacy_suspend_late(dev);1075 1076	if (pm && pm->freeze_noirq) {1077		int error;1078 1079		error = pm->freeze_noirq(dev);1080		suspend_report_result(dev, pm->freeze_noirq, error);1081		if (error)1082			return error;1083	}1084 1085	if (!pci_dev->state_saved)1086		pci_save_state(pci_dev);1087 1088	pci_pm_set_unknown_state(pci_dev);1089 1090	return 0;1091}1092 1093static int pci_pm_thaw_noirq(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 1098	/*1099	 * The pm->thaw_noirq() callback assumes the device has been1100	 * returned to D0 and its config state has been restored.1101	 *1102	 * In addition, pci_restore_state() restores MSI-X state in MMIO1103	 * space, which requires the device to be in D0, so return it to D01104	 * in case the driver's "freeze" callbacks put it into a low-power1105	 * state.1106	 */1107	pci_pm_power_up_and_verify_state(pci_dev);1108	pci_restore_state(pci_dev);1109 1110	if (pci_has_legacy_pm_support(pci_dev))1111		return 0;1112 1113	if (pm && pm->thaw_noirq)1114		return pm->thaw_noirq(dev);1115 1116	return 0;1117}1118 1119static int pci_pm_thaw(struct device *dev)1120{1121	struct pci_dev *pci_dev = to_pci_dev(dev);1122	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;1123	int error = 0;1124 1125	if (pci_has_legacy_pm_support(pci_dev))1126		return pci_legacy_resume(dev);1127 1128	if (pm) {1129		if (pm->thaw)1130			error = pm->thaw(dev);1131	} else {1132		pci_pm_reenable_device(pci_dev);1133	}1134 1135	pci_dev->state_saved = false;1136 1137	return error;1138}1139 1140static int pci_pm_poweroff(struct device *dev)1141{1142	struct pci_dev *pci_dev = to_pci_dev(dev);1143	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;1144 1145	if (pci_has_legacy_pm_support(pci_dev))1146		return pci_legacy_suspend(dev, PMSG_HIBERNATE);1147 1148	if (!pm) {1149		pci_pm_default_suspend(pci_dev);1150		return 0;1151	}1152 1153	/* The reason to do that is the same as in pci_pm_suspend(). */1154	if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||1155	    pci_dev_need_resume(pci_dev)) {1156		pm_runtime_resume(dev);1157		pci_dev->state_saved = false;1158	} else {1159		pci_dev_adjust_pme(pci_dev);1160	}1161 1162	if (pm->poweroff) {1163		int error;1164 1165		error = pm->poweroff(dev);1166		suspend_report_result(dev, pm->poweroff, error);1167		if (error)1168			return error;1169	}1170 1171	return 0;1172}1173 1174static int pci_pm_poweroff_late(struct device *dev)1175{1176	if (dev_pm_skip_suspend(dev))1177		return 0;1178 1179	pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev));1180 1181	return pm_generic_poweroff_late(dev);1182}1183 1184static int pci_pm_poweroff_noirq(struct device *dev)1185{1186	struct pci_dev *pci_dev = to_pci_dev(dev);1187	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;1188 1189	if (dev_pm_skip_suspend(dev))1190		return 0;1191 1192	if (pci_has_legacy_pm_support(pci_dev))1193		return pci_legacy_suspend_late(dev);1194 1195	if (!pm) {1196		pci_fixup_device(pci_fixup_suspend_late, pci_dev);1197		return 0;1198	}1199 1200	if (pm->poweroff_noirq) {1201		int error;1202 1203		error = pm->poweroff_noirq(dev);1204		suspend_report_result(dev, pm->poweroff_noirq, error);1205		if (error)1206			return error;1207	}1208 1209	if (!pci_dev->state_saved && !pci_has_subordinate(pci_dev))1210		pci_prepare_to_sleep(pci_dev);1211 1212	/*1213	 * The reason for doing this here is the same as for the analogous code1214	 * in pci_pm_suspend_noirq().1215	 */1216	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)1217		pci_write_config_word(pci_dev, PCI_COMMAND, 0);1218 1219	pci_fixup_device(pci_fixup_suspend_late, pci_dev);1220 1221	return 0;1222}1223 1224static int pci_pm_restore_noirq(struct device *dev)1225{1226	struct pci_dev *pci_dev = to_pci_dev(dev);1227	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;1228 1229	pci_pm_default_resume_early(pci_dev);1230	pci_fixup_device(pci_fixup_resume_early, pci_dev);1231 1232	if (pci_has_legacy_pm_support(pci_dev))1233		return 0;1234 1235	if (pm && pm->restore_noirq)1236		return pm->restore_noirq(dev);1237 1238	return 0;1239}1240 1241static int pci_pm_restore(struct device *dev)1242{1243	struct pci_dev *pci_dev = to_pci_dev(dev);1244	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;1245 1246	/*1247	 * This is necessary for the hibernation error path in which restore is1248	 * called without restoring the standard config registers of the device.1249	 */1250	if (pci_dev->state_saved)1251		pci_restore_standard_config(pci_dev);1252 1253	if (pci_has_legacy_pm_support(pci_dev))1254		return pci_legacy_resume(dev);1255 1256	pci_pm_default_resume(pci_dev);1257 1258	if (pm) {1259		if (pm->restore)1260			return pm->restore(dev);1261	} else {1262		pci_pm_reenable_device(pci_dev);1263	}1264 1265	return 0;1266}1267 1268#else /* !CONFIG_HIBERNATE_CALLBACKS */1269 1270#define pci_pm_freeze		NULL1271#define pci_pm_freeze_noirq	NULL1272#define pci_pm_thaw		NULL1273#define pci_pm_thaw_noirq	NULL1274#define pci_pm_poweroff		NULL1275#define pci_pm_poweroff_late	NULL1276#define pci_pm_poweroff_noirq	NULL1277#define pci_pm_restore		NULL1278#define pci_pm_restore_noirq	NULL1279 1280#endif /* !CONFIG_HIBERNATE_CALLBACKS */1281 1282#ifdef CONFIG_PM1283 1284static int pci_pm_runtime_suspend(struct device *dev)1285{1286	struct pci_dev *pci_dev = to_pci_dev(dev);1287	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;1288	pci_power_t prev = pci_dev->current_state;1289	int error;1290 1291	pci_suspend_ptm(pci_dev);1292 1293	/*1294	 * If pci_dev->driver is not set (unbound), we leave the device in D0,1295	 * but it may go to D3cold when the bridge above it runtime suspends.1296	 * Save its config space in case that happens.1297	 */1298	if (!pci_dev->driver) {1299		pci_save_state(pci_dev);1300		return 0;1301	}1302 1303	pci_dev->state_saved = false;1304	if (pm && pm->runtime_suspend) {1305		error = pm->runtime_suspend(dev);1306		/*1307		 * -EBUSY and -EAGAIN is used to request the runtime PM core1308		 * to schedule a new suspend, so log the event only with debug1309		 * log level.1310		 */1311		if (error == -EBUSY || error == -EAGAIN) {1312			pci_dbg(pci_dev, "can't suspend now (%ps returned %d)\n",1313				pm->runtime_suspend, error);1314			return error;1315		} else if (error) {1316			pci_err(pci_dev, "can't suspend (%ps returned %d)\n",1317				pm->runtime_suspend, error);1318			return error;1319		}1320	}1321 1322	pci_fixup_device(pci_fixup_suspend, pci_dev);1323 1324	if (pm && pm->runtime_suspend1325	    && !pci_dev->state_saved && pci_dev->current_state != PCI_D01326	    && pci_dev->current_state != PCI_UNKNOWN) {1327		pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,1328			      "PCI PM: State of device not saved by %pS\n",1329			      pm->runtime_suspend);1330		return 0;1331	}1332 1333	if (!pci_dev->state_saved) {1334		pci_save_state(pci_dev);1335		pci_finish_runtime_suspend(pci_dev);1336	}1337 1338	return 0;1339}1340 1341static int pci_pm_runtime_resume(struct device *dev)1342{1343	struct pci_dev *pci_dev = to_pci_dev(dev);1344	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;1345	pci_power_t prev_state = pci_dev->current_state;1346	int error = 0;1347 1348	/*1349	 * Restoring config space is necessary even if the device is not bound1350	 * to a driver because although we left it in D0, it may have gone to1351	 * D3cold when the bridge above it runtime suspended.1352	 */1353	pci_pm_default_resume_early(pci_dev);1354	pci_resume_ptm(pci_dev);1355 1356	if (!pci_dev->driver)1357		return 0;1358 1359	pci_fixup_device(pci_fixup_resume_early, pci_dev);1360	pci_pm_default_resume(pci_dev);1361 1362	if (prev_state == PCI_D3cold)1363		pci_pm_bridge_power_up_actions(pci_dev);1364 1365	if (pm && pm->runtime_resume)1366		error = pm->runtime_resume(dev);1367 1368	return error;1369}1370 1371static int pci_pm_runtime_idle(struct device *dev)1372{1373	struct pci_dev *pci_dev = to_pci_dev(dev);1374	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;1375 1376	/*1377	 * If pci_dev->driver is not set (unbound), the device should1378	 * always remain in D0 regardless of the runtime PM status1379	 */1380	if (!pci_dev->driver)1381		return 0;1382 1383	if (pm && pm->runtime_idle)1384		return pm->runtime_idle(dev);1385 1386	return 0;1387}1388 1389static const struct dev_pm_ops pci_dev_pm_ops = {1390	.prepare = pci_pm_prepare,1391	.complete = pci_pm_complete,1392	.suspend = pci_pm_suspend,1393	.suspend_late = pci_pm_suspend_late,1394	.resume = pci_pm_resume,1395	.resume_early = pci_pm_resume_early,1396	.freeze = pci_pm_freeze,1397	.thaw = pci_pm_thaw,1398	.poweroff = pci_pm_poweroff,1399	.poweroff_late = pci_pm_poweroff_late,1400	.restore = pci_pm_restore,1401	.suspend_noirq = pci_pm_suspend_noirq,1402	.resume_noirq = pci_pm_resume_noirq,1403	.freeze_noirq = pci_pm_freeze_noirq,1404	.thaw_noirq = pci_pm_thaw_noirq,1405	.poweroff_noirq = pci_pm_poweroff_noirq,1406	.restore_noirq = pci_pm_restore_noirq,1407	.runtime_suspend = pci_pm_runtime_suspend,1408	.runtime_resume = pci_pm_runtime_resume,1409	.runtime_idle = pci_pm_runtime_idle,1410};1411 1412#define PCI_PM_OPS_PTR	(&pci_dev_pm_ops)1413 1414#else /* !CONFIG_PM */1415 1416#define pci_pm_runtime_suspend	NULL1417#define pci_pm_runtime_resume	NULL1418#define pci_pm_runtime_idle	NULL1419 1420#define PCI_PM_OPS_PTR	NULL1421 1422#endif /* !CONFIG_PM */1423 1424/**1425 * __pci_register_driver - register a new pci driver1426 * @drv: the driver structure to register1427 * @owner: owner module of drv1428 * @mod_name: module name string1429 *1430 * Adds the driver structure to the list of registered drivers.1431 * Returns a negative value on error, otherwise 0.1432 * If no error occurred, the driver remains registered even if1433 * no device was claimed during registration.1434 */1435int __pci_register_driver(struct pci_driver *drv, struct module *owner,1436			  const char *mod_name)1437{1438	/* initialize common driver fields */1439	drv->driver.name = drv->name;1440	drv->driver.bus = &pci_bus_type;1441	drv->driver.owner = owner;1442	drv->driver.mod_name = mod_name;1443	drv->driver.groups = drv->groups;1444	drv->driver.dev_groups = drv->dev_groups;1445 1446	spin_lock_init(&drv->dynids.lock);1447	INIT_LIST_HEAD(&drv->dynids.list);1448 1449	/* register with core */1450	return driver_register(&drv->driver);1451}1452EXPORT_SYMBOL(__pci_register_driver);1453 1454/**1455 * pci_unregister_driver - unregister a pci driver1456 * @drv: the driver structure to unregister1457 *1458 * Deletes the driver structure from the list of registered PCI drivers,1459 * gives it a chance to clean up by calling its remove() function for1460 * each device it was responsible for, and marks those devices as1461 * driverless.1462 */1463 1464void pci_unregister_driver(struct pci_driver *drv)1465{1466	driver_unregister(&drv->driver);1467	pci_free_dynids(drv);1468}1469EXPORT_SYMBOL(pci_unregister_driver);1470 1471static struct pci_driver pci_compat_driver = {1472	.name = "compat"1473};1474 1475/**1476 * pci_dev_driver - get the pci_driver of a device1477 * @dev: the device to query1478 *1479 * Returns the appropriate pci_driver structure or %NULL if there is no1480 * registered driver for the device.1481 */1482struct pci_driver *pci_dev_driver(const struct pci_dev *dev)1483{1484	int i;1485 1486	if (dev->driver)1487		return dev->driver;1488 1489	for (i = 0; i <= PCI_ROM_RESOURCE; i++)1490		if (dev->resource[i].flags & IORESOURCE_BUSY)1491			return &pci_compat_driver;1492 1493	return NULL;1494}1495EXPORT_SYMBOL(pci_dev_driver);1496 1497/**1498 * pci_bus_match - Tell if a PCI device structure has a matching PCI device id structure1499 * @dev: the PCI device structure to match against1500 * @drv: the device driver to search for matching PCI device id structures1501 *1502 * Used by a driver to check whether a PCI device present in the1503 * system is in its list of supported devices. Returns the matching1504 * pci_device_id structure or %NULL if there is no match.1505 */1506static int pci_bus_match(struct device *dev, const struct device_driver *drv)1507{1508	struct pci_dev *pci_dev = to_pci_dev(dev);1509	struct pci_driver *pci_drv;1510	const struct pci_device_id *found_id;1511 1512	if (!pci_dev->match_driver)1513		return 0;1514 1515	pci_drv = (struct pci_driver *)to_pci_driver(drv);1516	found_id = pci_match_device(pci_drv, pci_dev);1517	if (found_id)1518		return 1;1519 1520	return 0;1521}1522 1523/**1524 * pci_dev_get - increments the reference count of the pci device structure1525 * @dev: the device being referenced1526 *1527 * Each live reference to a device should be refcounted.1528 *1529 * Drivers for PCI devices should normally record such references in1530 * their probe() methods, when they bind to a device, and release1531 * them by calling pci_dev_put(), in their disconnect() methods.1532 *1533 * A pointer to the device with the incremented reference counter is returned.1534 */1535struct pci_dev *pci_dev_get(struct pci_dev *dev)1536{1537	if (dev)1538		get_device(&dev->dev);1539	return dev;1540}1541EXPORT_SYMBOL(pci_dev_get);1542 1543/**1544 * pci_dev_put - release a use of the pci device structure1545 * @dev: device that's been disconnected1546 *1547 * Must be called when a user of a device is finished with it.  When the last1548 * user of the device calls this function, the memory of the device is freed.1549 */1550void pci_dev_put(struct pci_dev *dev)1551{1552	if (dev)1553		put_device(&dev->dev);1554}1555EXPORT_SYMBOL(pci_dev_put);1556 1557static int pci_uevent(const struct device *dev, struct kobj_uevent_env *env)1558{1559	const struct pci_dev *pdev;1560 1561	if (!dev)1562		return -ENODEV;1563 1564	pdev = to_pci_dev(dev);1565 1566	if (add_uevent_var(env, "PCI_CLASS=%04X", pdev->class))1567		return -ENOMEM;1568 1569	if (add_uevent_var(env, "PCI_ID=%04X:%04X", pdev->vendor, pdev->device))1570		return -ENOMEM;1571 1572	if (add_uevent_var(env, "PCI_SUBSYS_ID=%04X:%04X", pdev->subsystem_vendor,1573			   pdev->subsystem_device))1574		return -ENOMEM;1575 1576	if (add_uevent_var(env, "PCI_SLOT_NAME=%s", pci_name(pdev)))1577		return -ENOMEM;1578 1579	if (add_uevent_var(env, "MODALIAS=pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02X",1580			   pdev->vendor, pdev->device,1581			   pdev->subsystem_vendor, pdev->subsystem_device,1582			   (u8)(pdev->class >> 16), (u8)(pdev->class >> 8),1583			   (u8)(pdev->class)))1584		return -ENOMEM;1585 1586	return 0;1587}1588 1589#if defined(CONFIG_PCIEAER) || defined(CONFIG_EEH)1590/**1591 * pci_uevent_ers - emit a uevent during recovery path of PCI device1592 * @pdev: PCI device undergoing error recovery1593 * @err_type: type of error event1594 */1595void pci_uevent_ers(struct pci_dev *pdev, enum pci_ers_result err_type)1596{1597	int idx = 0;1598	char *envp[3];1599 1600	switch (err_type) {1601	case PCI_ERS_RESULT_NONE:1602	case PCI_ERS_RESULT_CAN_RECOVER:1603		envp[idx++] = "ERROR_EVENT=BEGIN_RECOVERY";1604		envp[idx++] = "DEVICE_ONLINE=0";1605		break;1606	case PCI_ERS_RESULT_RECOVERED:1607		envp[idx++] = "ERROR_EVENT=SUCCESSFUL_RECOVERY";1608		envp[idx++] = "DEVICE_ONLINE=1";1609		break;1610	case PCI_ERS_RESULT_DISCONNECT:1611		envp[idx++] = "ERROR_EVENT=FAILED_RECOVERY";1612		envp[idx++] = "DEVICE_ONLINE=0";1613		break;1614	default:1615		break;1616	}1617 1618	if (idx > 0) {1619		envp[idx++] = NULL;1620		kobject_uevent_env(&pdev->dev.kobj, KOBJ_CHANGE, envp);1621	}1622}1623#endif1624 1625static int pci_bus_num_vf(struct device *dev)1626{1627	return pci_num_vf(to_pci_dev(dev));1628}1629 1630/**1631 * pci_dma_configure - Setup DMA configuration1632 * @dev: ptr to dev structure1633 *1634 * Function to update PCI devices's DMA configuration using the same1635 * info from the OF node or ACPI node of host bridge's parent (if any).1636 */1637static int pci_dma_configure(struct device *dev)1638{1639	struct pci_driver *driver = to_pci_driver(dev->driver);1640	struct device *bridge;1641	int ret = 0;1642 1643	bridge = pci_get_host_bridge_device(to_pci_dev(dev));1644 1645	if (IS_ENABLED(CONFIG_OF) && bridge->parent &&1646	    bridge->parent->of_node) {1647		ret = of_dma_configure(dev, bridge->parent->of_node, true);1648	} else if (has_acpi_companion(bridge)) {1649		struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);1650 1651		ret = acpi_dma_configure(dev, acpi_get_dma_attr(adev));1652	}1653 1654	pci_put_host_bridge_device(bridge);1655 1656	if (!ret && !driver->driver_managed_dma) {1657		ret = iommu_device_use_default_domain(dev);1658		if (ret)1659			arch_teardown_dma_ops(dev);1660	}1661 1662	return ret;1663}1664 1665static void pci_dma_cleanup(struct device *dev)1666{1667	struct pci_driver *driver = to_pci_driver(dev->driver);1668 1669	if (!driver->driver_managed_dma)1670		iommu_device_unuse_default_domain(dev);1671}1672 1673const struct bus_type pci_bus_type = {1674	.name		= "pci",1675	.match		= pci_bus_match,1676	.uevent		= pci_uevent,1677	.probe		= pci_device_probe,1678	.remove		= pci_device_remove,1679	.shutdown	= pci_device_shutdown,1680	.dev_groups	= pci_dev_groups,1681	.bus_groups	= pci_bus_groups,1682	.drv_groups	= pci_drv_groups,1683	.pm		= PCI_PM_OPS_PTR,1684	.num_vf		= pci_bus_num_vf,1685	.dma_configure	= pci_dma_configure,1686	.dma_cleanup	= pci_dma_cleanup,1687};1688EXPORT_SYMBOL(pci_bus_type);1689 1690#ifdef CONFIG_PCIEPORTBUS1691static int pcie_port_bus_match(struct device *dev, const struct device_driver *drv)1692{1693	struct pcie_device *pciedev;1694	const struct pcie_port_service_driver *driver;1695 1696	if (drv->bus != &pcie_port_bus_type || dev->bus != &pcie_port_bus_type)1697		return 0;1698 1699	pciedev = to_pcie_device(dev);1700	driver = to_service_driver(drv);1701 1702	if (driver->service != pciedev->service)1703		return 0;1704 1705	if (driver->port_type != PCIE_ANY_PORT &&1706	    driver->port_type != pci_pcie_type(pciedev->port))1707		return 0;1708 1709	return 1;1710}1711 1712const struct bus_type pcie_port_bus_type = {1713	.name		= "pci_express",1714	.match		= pcie_port_bus_match,1715};1716#endif1717 1718static int __init pci_driver_init(void)1719{1720	int ret;1721 1722	ret = bus_register(&pci_bus_type);1723	if (ret)1724		return ret;1725 1726#ifdef CONFIG_PCIEPORTBUS1727	ret = bus_register(&pcie_port_bus_type);1728	if (ret)1729		return ret;1730#endif1731	dma_debug_add_bus(&pci_bus_type);1732	return 0;1733}1734postcore_initcall(pci_driver_init);1735