linuxdebug/drivers/pci/pci-driver.c

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2024-07-16 15:50:57 +02:00
// SPDX-License-Identifier: GPL-2.0
/*
* (C) Copyright 2002-2004, 2007 Greg Kroah-Hartman <greg@kroah.com>
* (C) Copyright 2007 Novell Inc.
*/
#include <linux/pci.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/mempolicy.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/sched/isolation.h>
#include <linux/cpu.h>
#include <linux/pm_runtime.h>
#include <linux/suspend.h>
#include <linux/kexec.h>
#include <linux/of_device.h>
#include <linux/acpi.h>
#include <linux/dma-map-ops.h>
#include <linux/iommu.h>
#include "pci.h"
#include "pcie/portdrv.h"
struct pci_dynid {
struct list_head node;
struct pci_device_id id;
};
/**
* pci_add_dynid - add a new PCI device ID to this driver and re-probe devices
* @drv: target pci driver
* @vendor: PCI vendor ID
* @device: PCI device ID
* @subvendor: PCI subvendor ID
* @subdevice: PCI subdevice ID
* @class: PCI class
* @class_mask: PCI class mask
* @driver_data: private driver data
*
* Adds a new dynamic pci device ID to this driver and causes the
* driver to probe for all devices again. @drv must have been
* registered prior to calling this function.
*
* CONTEXT:
* Does GFP_KERNEL allocation.
*
* RETURNS:
* 0 on success, -errno on failure.
*/
int pci_add_dynid(struct pci_driver *drv,
unsigned int vendor, unsigned int device,
unsigned int subvendor, unsigned int subdevice,
unsigned int class, unsigned int class_mask,
unsigned long driver_data)
{
struct pci_dynid *dynid;
dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
if (!dynid)
return -ENOMEM;
dynid->id.vendor = vendor;
dynid->id.device = device;
dynid->id.subvendor = subvendor;
dynid->id.subdevice = subdevice;
dynid->id.class = class;
dynid->id.class_mask = class_mask;
dynid->id.driver_data = driver_data;
spin_lock(&drv->dynids.lock);
list_add_tail(&dynid->node, &drv->dynids.list);
spin_unlock(&drv->dynids.lock);
return driver_attach(&drv->driver);
}
EXPORT_SYMBOL_GPL(pci_add_dynid);
static void pci_free_dynids(struct pci_driver *drv)
{
struct pci_dynid *dynid, *n;
spin_lock(&drv->dynids.lock);
list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
list_del(&dynid->node);
kfree(dynid);
}
spin_unlock(&drv->dynids.lock);
}
/**
* pci_match_id - See if a PCI device matches a given pci_id table
* @ids: array of PCI device ID structures to search in
* @dev: the PCI device structure to match against.
*
* Used by a driver to check whether a PCI device is in its list of
* supported devices. Returns the matching pci_device_id structure or
* %NULL if there is no match.
*
* Deprecated; don't use this as it will not catch any dynamic IDs
* that a driver might want to check for.
*/
const struct pci_device_id *pci_match_id(const struct pci_device_id *ids,
struct pci_dev *dev)
{
if (ids) {
while (ids->vendor || ids->subvendor || ids->class_mask) {
if (pci_match_one_device(ids, dev))
return ids;
ids++;
}
}
return NULL;
}
EXPORT_SYMBOL(pci_match_id);
static const struct pci_device_id pci_device_id_any = {
.vendor = PCI_ANY_ID,
.device = PCI_ANY_ID,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
};
/**
* pci_match_device - See if a device matches a driver's list of IDs
* @drv: the PCI driver to match against
* @dev: the PCI device structure to match against
*
* Used by a driver to check whether a PCI device is in its list of
* supported devices or in the dynids list, which may have been augmented
* via the sysfs "new_id" file. Returns the matching pci_device_id
* structure or %NULL if there is no match.
*/
static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
struct pci_dev *dev)
{
struct pci_dynid *dynid;
const struct pci_device_id *found_id = NULL, *ids;
/* When driver_override is set, only bind to the matching driver */
if (dev->driver_override && strcmp(dev->driver_override, drv->name))
return NULL;
/* Look at the dynamic ids first, before the static ones */
spin_lock(&drv->dynids.lock);
list_for_each_entry(dynid, &drv->dynids.list, node) {
if (pci_match_one_device(&dynid->id, dev)) {
found_id = &dynid->id;
break;
}
}
spin_unlock(&drv->dynids.lock);
if (found_id)
return found_id;
for (ids = drv->id_table; (found_id = pci_match_id(ids, dev));
ids = found_id + 1) {
/*
* The match table is split based on driver_override.
* In case override_only was set, enforce driver_override
* matching.
*/
if (found_id->override_only) {
if (dev->driver_override)
return found_id;
} else {
return found_id;
}
}
/* driver_override will always match, send a dummy id */
if (dev->driver_override)
return &pci_device_id_any;
return NULL;
}
/**
* new_id_store - sysfs frontend to pci_add_dynid()
* @driver: target device driver
* @buf: buffer for scanning device ID data
* @count: input size
*
* Allow PCI IDs to be added to an existing driver via sysfs.
*/
static ssize_t new_id_store(struct device_driver *driver, const char *buf,
size_t count)
{
struct pci_driver *pdrv = to_pci_driver(driver);
const struct pci_device_id *ids = pdrv->id_table;
u32 vendor, device, subvendor = PCI_ANY_ID,
subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
unsigned long driver_data = 0;
int fields = 0;
int retval = 0;
fields = sscanf(buf, "%x %x %x %x %x %x %lx",
&vendor, &device, &subvendor, &subdevice,
&class, &class_mask, &driver_data);
if (fields < 2)
return -EINVAL;
if (fields != 7) {
struct pci_dev *pdev = kzalloc(sizeof(*pdev), GFP_KERNEL);
if (!pdev)
return -ENOMEM;
pdev->vendor = vendor;
pdev->device = device;
pdev->subsystem_vendor = subvendor;
pdev->subsystem_device = subdevice;
pdev->class = class;
if (pci_match_device(pdrv, pdev))
retval = -EEXIST;
kfree(pdev);
if (retval)
return retval;
}
/* Only accept driver_data values that match an existing id_table
entry */
if (ids) {
retval = -EINVAL;
while (ids->vendor || ids->subvendor || ids->class_mask) {
if (driver_data == ids->driver_data) {
retval = 0;
break;
}
ids++;
}
if (retval) /* No match */
return retval;
}
retval = pci_add_dynid(pdrv, vendor, device, subvendor, subdevice,
class, class_mask, driver_data);
if (retval)
return retval;
return count;
}
static DRIVER_ATTR_WO(new_id);
/**
* remove_id_store - remove a PCI device ID from this driver
* @driver: target device driver
* @buf: buffer for scanning device ID data
* @count: input size
*
* Removes a dynamic pci device ID to this driver.
*/
static ssize_t remove_id_store(struct device_driver *driver, const char *buf,
size_t count)
{
struct pci_dynid *dynid, *n;
struct pci_driver *pdrv = to_pci_driver(driver);
u32 vendor, device, subvendor = PCI_ANY_ID,
subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
int fields = 0;
size_t retval = -ENODEV;
fields = sscanf(buf, "%x %x %x %x %x %x",
&vendor, &device, &subvendor, &subdevice,
&class, &class_mask);
if (fields < 2)
return -EINVAL;
spin_lock(&pdrv->dynids.lock);
list_for_each_entry_safe(dynid, n, &pdrv->dynids.list, node) {
struct pci_device_id *id = &dynid->id;
if ((id->vendor == vendor) &&
(id->device == device) &&
(subvendor == PCI_ANY_ID || id->subvendor == subvendor) &&
(subdevice == PCI_ANY_ID || id->subdevice == subdevice) &&
!((id->class ^ class) & class_mask)) {
list_del(&dynid->node);
kfree(dynid);
retval = count;
break;
}
}
spin_unlock(&pdrv->dynids.lock);
return retval;
}
static DRIVER_ATTR_WO(remove_id);
static struct attribute *pci_drv_attrs[] = {
&driver_attr_new_id.attr,
&driver_attr_remove_id.attr,
NULL,
};
ATTRIBUTE_GROUPS(pci_drv);
struct drv_dev_and_id {
struct pci_driver *drv;
struct pci_dev *dev;
const struct pci_device_id *id;
};
static long local_pci_probe(void *_ddi)
{
struct drv_dev_and_id *ddi = _ddi;
struct pci_dev *pci_dev = ddi->dev;
struct pci_driver *pci_drv = ddi->drv;
struct device *dev = &pci_dev->dev;
int rc;
/*
* Unbound PCI devices are always put in D0, regardless of
* runtime PM status. During probe, the device is set to
* active and the usage count is incremented. If the driver
* supports runtime PM, it should call pm_runtime_put_noidle(),
* or any other runtime PM helper function decrementing the usage
* count, in its probe routine and pm_runtime_get_noresume() in
* its remove routine.
*/
pm_runtime_get_sync(dev);
pci_dev->driver = pci_drv;
rc = pci_drv->probe(pci_dev, ddi->id);
if (!rc)
return rc;
if (rc < 0) {
pci_dev->driver = NULL;
pm_runtime_put_sync(dev);
return rc;
}
/*
* Probe function should return < 0 for failure, 0 for success
* Treat values > 0 as success, but warn.
*/
pci_warn(pci_dev, "Driver probe function unexpectedly returned %d\n",
rc);
return 0;
}
static bool pci_physfn_is_probed(struct pci_dev *dev)
{
#ifdef CONFIG_PCI_IOV
return dev->is_virtfn && dev->physfn->is_probed;
#else
return false;
#endif
}
static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
const struct pci_device_id *id)
{
int error, node, cpu;
struct drv_dev_and_id ddi = { drv, dev, id };
/*
* Execute driver initialization on node where the device is
* attached. This way the driver likely allocates its local memory
* on the right node.
*/
node = dev_to_node(&dev->dev);
dev->is_probed = 1;
cpu_hotplug_disable();
/*
* Prevent nesting work_on_cpu() for the case where a Virtual Function
* device is probed from work_on_cpu() of the Physical device.
*/
if (node < 0 || node >= MAX_NUMNODES || !node_online(node) ||
pci_physfn_is_probed(dev)) {
cpu = nr_cpu_ids;
} else {
cpumask_var_t wq_domain_mask;
if (!zalloc_cpumask_var(&wq_domain_mask, GFP_KERNEL)) {
error = -ENOMEM;
goto out;
}
cpumask_and(wq_domain_mask,
housekeeping_cpumask(HK_TYPE_WQ),
housekeeping_cpumask(HK_TYPE_DOMAIN));
cpu = cpumask_any_and(cpumask_of_node(node),
wq_domain_mask);
free_cpumask_var(wq_domain_mask);
}
if (cpu < nr_cpu_ids)
error = work_on_cpu(cpu, local_pci_probe, &ddi);
else
error = local_pci_probe(&ddi);
out:
dev->is_probed = 0;
cpu_hotplug_enable();
return error;
}
/**
* __pci_device_probe - check if a driver wants to claim a specific PCI device
* @drv: driver to call to check if it wants the PCI device
* @pci_dev: PCI device being probed
*
* returns 0 on success, else error.
* side-effect: pci_dev->driver is set to drv when drv claims pci_dev.
*/
static int __pci_device_probe(struct pci_driver *drv, struct pci_dev *pci_dev)
{
const struct pci_device_id *id;
int error = 0;
if (drv->probe) {
error = -ENODEV;
id = pci_match_device(drv, pci_dev);
if (id)
error = pci_call_probe(drv, pci_dev, id);
}
return error;
}
int __weak pcibios_alloc_irq(struct pci_dev *dev)
{
return 0;
}
void __weak pcibios_free_irq(struct pci_dev *dev)
{
}
#ifdef CONFIG_PCI_IOV
static inline bool pci_device_can_probe(struct pci_dev *pdev)
{
return (!pdev->is_virtfn || pdev->physfn->sriov->drivers_autoprobe ||
pdev->driver_override);
}
#else
static inline bool pci_device_can_probe(struct pci_dev *pdev)
{
return true;
}
#endif
static int pci_device_probe(struct device *dev)
{
int error;
struct pci_dev *pci_dev = to_pci_dev(dev);
struct pci_driver *drv = to_pci_driver(dev->driver);
if (!pci_device_can_probe(pci_dev))
return -ENODEV;
pci_assign_irq(pci_dev);
error = pcibios_alloc_irq(pci_dev);
if (error < 0)
return error;
pci_dev_get(pci_dev);
error = __pci_device_probe(drv, pci_dev);
if (error) {
pcibios_free_irq(pci_dev);
pci_dev_put(pci_dev);
}
return error;
}
static void pci_device_remove(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
struct pci_driver *drv = pci_dev->driver;
if (drv->remove) {
pm_runtime_get_sync(dev);
drv->remove(pci_dev);
pm_runtime_put_noidle(dev);
}
pcibios_free_irq(pci_dev);
pci_dev->driver = NULL;
pci_iov_remove(pci_dev);
/* Undo the runtime PM settings in local_pci_probe() */
pm_runtime_put_sync(dev);
/*
* If the device is still on, set the power state as "unknown",
* since it might change by the next time we load the driver.
*/
if (pci_dev->current_state == PCI_D0)
pci_dev->current_state = PCI_UNKNOWN;
/*
* We would love to complain here if pci_dev->is_enabled is set, that
* the driver should have called pci_disable_device(), but the
* unfortunate fact is there are too many odd BIOS and bridge setups
* that don't like drivers doing that all of the time.
* Oh well, we can dream of sane hardware when we sleep, no matter how
* horrible the crap we have to deal with is when we are awake...
*/
pci_dev_put(pci_dev);
}
static void pci_device_shutdown(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
struct pci_driver *drv = pci_dev->driver;
pm_runtime_resume(dev);
if (drv && drv->shutdown)
drv->shutdown(pci_dev);
/*
* If this is a kexec reboot, turn off Bus Master bit on the
* device to tell it to not continue to do DMA. Don't touch
* devices in D3cold or unknown states.
* If it is not a kexec reboot, firmware will hit the PCI
* devices with big hammer and stop their DMA any way.
*/
if (kexec_in_progress && (pci_dev->current_state <= PCI_D3hot))
pci_clear_master(pci_dev);
}
#ifdef CONFIG_PM_SLEEP
/* Auxiliary functions used for system resume */
/**
* pci_restore_standard_config - restore standard config registers of PCI device
* @pci_dev: PCI device to handle
*/
static int pci_restore_standard_config(struct pci_dev *pci_dev)
{
pci_update_current_state(pci_dev, PCI_UNKNOWN);
if (pci_dev->current_state != PCI_D0) {
int error = pci_set_power_state(pci_dev, PCI_D0);
if (error)
return error;
}
pci_restore_state(pci_dev);
pci_pme_restore(pci_dev);
return 0;
}
#endif /* CONFIG_PM_SLEEP */
#ifdef CONFIG_PM
/* Auxiliary functions used for system resume and run-time resume */
static void pci_pm_default_resume(struct pci_dev *pci_dev)
{
pci_fixup_device(pci_fixup_resume, pci_dev);
pci_enable_wake(pci_dev, PCI_D0, false);
}
static void pci_pm_power_up_and_verify_state(struct pci_dev *pci_dev)
{
pci_power_up(pci_dev);
pci_update_current_state(pci_dev, PCI_D0);
}
static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
{
pci_pm_power_up_and_verify_state(pci_dev);
pci_restore_state(pci_dev);
pci_pme_restore(pci_dev);
}
static void pci_pm_bridge_power_up_actions(struct pci_dev *pci_dev)
{
pci_bridge_wait_for_secondary_bus(pci_dev, "resume", PCI_RESET_WAIT);
/*
* When powering on a bridge from D3cold, the whole hierarchy may be
* powered on into D0uninitialized state, resume them to give them a
* chance to suspend again
*/
pci_resume_bus(pci_dev->subordinate);
}
#endif /* CONFIG_PM */
#ifdef CONFIG_PM_SLEEP
/*
* Default "suspend" method for devices that have no driver provided suspend,
* or not even a driver at all (second part).
*/
static void pci_pm_set_unknown_state(struct pci_dev *pci_dev)
{
/*
* mark its power state as "unknown", since we don't know if
* e.g. the BIOS will change its device state when we suspend.
*/
if (pci_dev->current_state == PCI_D0)
pci_dev->current_state = PCI_UNKNOWN;
}
/*
* Default "resume" method for devices that have no driver provided resume,
* or not even a driver at all (second part).
*/
static int pci_pm_reenable_device(struct pci_dev *pci_dev)
{
int retval;
/* if the device was enabled before suspend, re-enable */
retval = pci_reenable_device(pci_dev);
/*
* if the device was busmaster before the suspend, make it busmaster
* again
*/
if (pci_dev->is_busmaster)
pci_set_master(pci_dev);
return retval;
}
static int pci_legacy_suspend(struct device *dev, pm_message_t state)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
struct pci_driver *drv = pci_dev->driver;
if (drv && drv->suspend) {
pci_power_t prev = pci_dev->current_state;
int error;
error = drv->suspend(pci_dev, state);
suspend_report_result(dev, drv->suspend, error);
if (error)
return error;
if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
&& pci_dev->current_state != PCI_UNKNOWN) {
pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
"PCI PM: Device state not saved by %pS\n",
drv->suspend);
}
}
pci_fixup_device(pci_fixup_suspend, pci_dev);
return 0;
}
static int pci_legacy_suspend_late(struct device *dev, pm_message_t state)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
if (!pci_dev->state_saved)
pci_save_state(pci_dev);
pci_pm_set_unknown_state(pci_dev);
pci_fixup_device(pci_fixup_suspend_late, pci_dev);
return 0;
}
static int pci_legacy_resume(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
struct pci_driver *drv = pci_dev->driver;
pci_fixup_device(pci_fixup_resume, pci_dev);
return drv && drv->resume ?
drv->resume(pci_dev) : pci_pm_reenable_device(pci_dev);
}
/* Auxiliary functions used by the new power management framework */
static void pci_pm_default_suspend(struct pci_dev *pci_dev)
{
/* Disable non-bridge devices without PM support */
if (!pci_has_subordinate(pci_dev))
pci_disable_enabled_device(pci_dev);
}
static bool pci_has_legacy_pm_support(struct pci_dev *pci_dev)
{
struct pci_driver *drv = pci_dev->driver;
bool ret = drv && (drv->suspend || drv->resume);
/*
* Legacy PM support is used by default, so warn if the new framework is
* supported as well. Drivers are supposed to support either the
* former, or the latter, but not both at the same time.
*/
pci_WARN(pci_dev, ret && drv->driver.pm, "device %04x:%04x\n",
pci_dev->vendor, pci_dev->device);
return ret;
}
/* New power management framework */
static int pci_pm_prepare(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
if (pm && pm->prepare) {
int error = pm->prepare(dev);
if (error < 0)
return error;
if (!error && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
return 0;
}
if (pci_dev_need_resume(pci_dev))
return 0;
/*
* The PME setting needs to be adjusted here in case the direct-complete
* optimization is used with respect to this device.
*/
pci_dev_adjust_pme(pci_dev);
return 1;
}
static void pci_pm_complete(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
pci_dev_complete_resume(pci_dev);
pm_generic_complete(dev);
/* Resume device if platform firmware has put it in reset-power-on */
if (pm_runtime_suspended(dev) && pm_resume_via_firmware()) {
pci_power_t pre_sleep_state = pci_dev->current_state;
pci_refresh_power_state(pci_dev);
/*
* On platforms with ACPI this check may also trigger for
* devices sharing power resources if one of those power
* resources has been activated as a result of a change of the
* power state of another device sharing it. However, in that
* case it is also better to resume the device, in general.
*/
if (pci_dev->current_state < pre_sleep_state)
pm_request_resume(dev);
}
}
#else /* !CONFIG_PM_SLEEP */
#define pci_pm_prepare NULL
#define pci_pm_complete NULL
#endif /* !CONFIG_PM_SLEEP */
#ifdef CONFIG_SUSPEND
static void pcie_pme_root_status_cleanup(struct pci_dev *pci_dev)
{
/*
* Some BIOSes forget to clear Root PME Status bits after system
* wakeup, which breaks ACPI-based runtime wakeup on PCI Express.
* Clear those bits now just in case (shouldn't hurt).
*/
if (pci_is_pcie(pci_dev) &&
(pci_pcie_type(pci_dev) == PCI_EXP_TYPE_ROOT_PORT ||
pci_pcie_type(pci_dev) == PCI_EXP_TYPE_RC_EC))
pcie_clear_root_pme_status(pci_dev);
}
static int pci_pm_suspend(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
pci_dev->skip_bus_pm = false;
/*
* Disabling PTM allows some systems, e.g., Intel mobile chips
* since Coffee Lake, to enter a lower-power PM state.
*/
pci_suspend_ptm(pci_dev);
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_suspend(dev, PMSG_SUSPEND);
if (!pm) {
pci_pm_default_suspend(pci_dev);
return 0;
}
/*
* PCI devices suspended at run time may need to be resumed at this
* point, because in general it may be necessary to reconfigure them for
* system suspend. Namely, if the device is expected to wake up the
* system from the sleep state, it may have to be reconfigured for this
* purpose, or if the device is not expected to wake up the system from
* the sleep state, it should be prevented from signaling wakeup events
* going forward.
*
* Also if the driver of the device does not indicate that its system
* suspend callbacks can cope with runtime-suspended devices, it is
* better to resume the device from runtime suspend here.
*/
if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
pci_dev_need_resume(pci_dev)) {
pm_runtime_resume(dev);
pci_dev->state_saved = false;
} else {
pci_dev_adjust_pme(pci_dev);
}
if (pm->suspend) {
pci_power_t prev = pci_dev->current_state;
int error;
error = pm->suspend(dev);
suspend_report_result(dev, pm->suspend, error);
if (error)
return error;
if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
&& pci_dev->current_state != PCI_UNKNOWN) {
pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
"PCI PM: State of device not saved by %pS\n",
pm->suspend);
}
}
return 0;
}
static int pci_pm_suspend_late(struct device *dev)
{
if (dev_pm_skip_suspend(dev))
return 0;
pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev));
return pm_generic_suspend_late(dev);
}
static int pci_pm_suspend_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
if (dev_pm_skip_suspend(dev))
return 0;
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_suspend_late(dev, PMSG_SUSPEND);
if (!pm) {
pci_save_state(pci_dev);
goto Fixup;
}
if (pm->suspend_noirq) {
pci_power_t prev = pci_dev->current_state;
int error;
error = pm->suspend_noirq(dev);
suspend_report_result(dev, pm->suspend_noirq, error);
if (error)
return error;
if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
&& pci_dev->current_state != PCI_UNKNOWN) {
pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
"PCI PM: State of device not saved by %pS\n",
pm->suspend_noirq);
goto Fixup;
}
}
if (!pci_dev->state_saved) {
pci_save_state(pci_dev);
/*
* If the device is a bridge with a child in D0 below it,
* it needs to stay in D0, so check skip_bus_pm to avoid
* putting it into a low-power state in that case.
*/
if (!pci_dev->skip_bus_pm && pci_power_manageable(pci_dev))
pci_prepare_to_sleep(pci_dev);
}
pci_dbg(pci_dev, "PCI PM: Suspend power state: %s\n",
pci_power_name(pci_dev->current_state));
if (pci_dev->current_state == PCI_D0) {
pci_dev->skip_bus_pm = true;
/*
* Per PCI PM r1.2, table 6-1, a bridge must be in D0 if any
* downstream device is in D0, so avoid changing the power state
* of the parent bridge by setting the skip_bus_pm flag for it.
*/
if (pci_dev->bus->self)
pci_dev->bus->self->skip_bus_pm = true;
}
if (pci_dev->skip_bus_pm && pm_suspend_no_platform()) {
pci_dbg(pci_dev, "PCI PM: Skipped\n");
goto Fixup;
}
pci_pm_set_unknown_state(pci_dev);
/*
* Some BIOSes from ASUS have a bug: If a USB EHCI host controller's
* PCI COMMAND register isn't 0, the BIOS assumes that the controller
* hasn't been quiesced and tries to turn it off. If the controller
* is already in D3, this can hang or cause memory corruption.
*
* Since the value of the COMMAND register doesn't matter once the
* device has been suspended, we can safely set it to 0 here.
*/
if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
pci_write_config_word(pci_dev, PCI_COMMAND, 0);
Fixup:
pci_fixup_device(pci_fixup_suspend_late, pci_dev);
/*
* If the target system sleep state is suspend-to-idle, it is sufficient
* to check whether or not the device's wakeup settings are good for
* runtime PM. Otherwise, the pm_resume_via_firmware() check will cause
* pci_pm_complete() to take care of fixing up the device's state
* anyway, if need be.
*/
if (device_can_wakeup(dev) && !device_may_wakeup(dev))
dev->power.may_skip_resume = false;
return 0;
}
static int pci_pm_resume_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
pci_power_t prev_state = pci_dev->current_state;
bool skip_bus_pm = pci_dev->skip_bus_pm;
if (dev_pm_skip_resume(dev))
return 0;
/*
* In the suspend-to-idle case, devices left in D0 during suspend will
* stay in D0, so it is not necessary to restore or update their
* configuration here and attempting to put them into D0 again is
* pointless, so avoid doing that.
*/
if (!(skip_bus_pm && pm_suspend_no_platform()))
pci_pm_default_resume_early(pci_dev);
pci_fixup_device(pci_fixup_resume_early, pci_dev);
pcie_pme_root_status_cleanup(pci_dev);
if (!skip_bus_pm && prev_state == PCI_D3cold)
pci_pm_bridge_power_up_actions(pci_dev);
if (pci_has_legacy_pm_support(pci_dev))
return 0;
if (pm && pm->resume_noirq)
return pm->resume_noirq(dev);
return 0;
}
static int pci_pm_resume_early(struct device *dev)
{
if (dev_pm_skip_resume(dev))
return 0;
return pm_generic_resume_early(dev);
}
static int pci_pm_resume(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
/*
* This is necessary for the suspend error path in which resume is
* called without restoring the standard config registers of the device.
*/
if (pci_dev->state_saved)
pci_restore_standard_config(pci_dev);
pci_resume_ptm(pci_dev);
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_resume(dev);
pci_pm_default_resume(pci_dev);
if (pm) {
if (pm->resume)
return pm->resume(dev);
} else {
pci_pm_reenable_device(pci_dev);
}
return 0;
}
#else /* !CONFIG_SUSPEND */
#define pci_pm_suspend NULL
#define pci_pm_suspend_late NULL
#define pci_pm_suspend_noirq NULL
#define pci_pm_resume NULL
#define pci_pm_resume_early NULL
#define pci_pm_resume_noirq NULL
#endif /* !CONFIG_SUSPEND */
#ifdef CONFIG_HIBERNATE_CALLBACKS
static int pci_pm_freeze(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_suspend(dev, PMSG_FREEZE);
if (!pm) {
pci_pm_default_suspend(pci_dev);
return 0;
}
/*
* Resume all runtime-suspended devices before creating a snapshot
* image of system memory, because the restore kernel generally cannot
* be expected to always handle them consistently and they need to be
* put into the runtime-active metastate during system resume anyway,
* so it is better to ensure that the state saved in the image will be
* always consistent with that.
*/
pm_runtime_resume(dev);
pci_dev->state_saved = false;
if (pm->freeze) {
int error;
error = pm->freeze(dev);
suspend_report_result(dev, pm->freeze, error);
if (error)
return error;
}
return 0;
}
static int pci_pm_freeze_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_suspend_late(dev, PMSG_FREEZE);
if (pm && pm->freeze_noirq) {
int error;
error = pm->freeze_noirq(dev);
suspend_report_result(dev, pm->freeze_noirq, error);
if (error)
return error;
}
if (!pci_dev->state_saved)
pci_save_state(pci_dev);
pci_pm_set_unknown_state(pci_dev);
return 0;
}
static int pci_pm_thaw_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
/*
* The pm->thaw_noirq() callback assumes the device has been
* returned to D0 and its config state has been restored.
*
* In addition, pci_restore_state() restores MSI-X state in MMIO
* space, which requires the device to be in D0, so return it to D0
* in case the driver's "freeze" callbacks put it into a low-power
* state.
*/
pci_pm_power_up_and_verify_state(pci_dev);
pci_restore_state(pci_dev);
if (pci_has_legacy_pm_support(pci_dev))
return 0;
if (pm && pm->thaw_noirq)
return pm->thaw_noirq(dev);
return 0;
}
static int pci_pm_thaw(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
int error = 0;
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_resume(dev);
if (pm) {
if (pm->thaw)
error = pm->thaw(dev);
} else {
pci_pm_reenable_device(pci_dev);
}
pci_dev->state_saved = false;
return error;
}
static int pci_pm_poweroff(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_suspend(dev, PMSG_HIBERNATE);
if (!pm) {
pci_pm_default_suspend(pci_dev);
return 0;
}
/* The reason to do that is the same as in pci_pm_suspend(). */
if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
pci_dev_need_resume(pci_dev)) {
pm_runtime_resume(dev);
pci_dev->state_saved = false;
} else {
pci_dev_adjust_pme(pci_dev);
}
if (pm->poweroff) {
int error;
error = pm->poweroff(dev);
suspend_report_result(dev, pm->poweroff, error);
if (error)
return error;
}
return 0;
}
static int pci_pm_poweroff_late(struct device *dev)
{
if (dev_pm_skip_suspend(dev))
return 0;
pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev));
return pm_generic_poweroff_late(dev);
}
static int pci_pm_poweroff_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
if (dev_pm_skip_suspend(dev))
return 0;
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_suspend_late(dev, PMSG_HIBERNATE);
if (!pm) {
pci_fixup_device(pci_fixup_suspend_late, pci_dev);
return 0;
}
if (pm->poweroff_noirq) {
int error;
error = pm->poweroff_noirq(dev);
suspend_report_result(dev, pm->poweroff_noirq, error);
if (error)
return error;
}
if (!pci_dev->state_saved && !pci_has_subordinate(pci_dev))
pci_prepare_to_sleep(pci_dev);
/*
* The reason for doing this here is the same as for the analogous code
* in pci_pm_suspend_noirq().
*/
if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
pci_write_config_word(pci_dev, PCI_COMMAND, 0);
pci_fixup_device(pci_fixup_suspend_late, pci_dev);
return 0;
}
static int pci_pm_restore_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
pci_pm_default_resume_early(pci_dev);
pci_fixup_device(pci_fixup_resume_early, pci_dev);
if (pci_has_legacy_pm_support(pci_dev))
return 0;
if (pm && pm->restore_noirq)
return pm->restore_noirq(dev);
return 0;
}
static int pci_pm_restore(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
/*
* This is necessary for the hibernation error path in which restore is
* called without restoring the standard config registers of the device.
*/
if (pci_dev->state_saved)
pci_restore_standard_config(pci_dev);
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_resume(dev);
pci_pm_default_resume(pci_dev);
if (pm) {
if (pm->restore)
return pm->restore(dev);
} else {
pci_pm_reenable_device(pci_dev);
}
return 0;
}
#else /* !CONFIG_HIBERNATE_CALLBACKS */
#define pci_pm_freeze NULL
#define pci_pm_freeze_noirq NULL
#define pci_pm_thaw NULL
#define pci_pm_thaw_noirq NULL
#define pci_pm_poweroff NULL
#define pci_pm_poweroff_late NULL
#define pci_pm_poweroff_noirq NULL
#define pci_pm_restore NULL
#define pci_pm_restore_noirq NULL
#endif /* !CONFIG_HIBERNATE_CALLBACKS */
#ifdef CONFIG_PM
static int pci_pm_runtime_suspend(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
pci_power_t prev = pci_dev->current_state;
int error;
pci_suspend_ptm(pci_dev);
/*
* If pci_dev->driver is not set (unbound), we leave the device in D0,
* but it may go to D3cold when the bridge above it runtime suspends.
* Save its config space in case that happens.
*/
if (!pci_dev->driver) {
pci_save_state(pci_dev);
return 0;
}
pci_dev->state_saved = false;
if (pm && pm->runtime_suspend) {
error = pm->runtime_suspend(dev);
/*
* -EBUSY and -EAGAIN is used to request the runtime PM core
* to schedule a new suspend, so log the event only with debug
* log level.
*/
if (error == -EBUSY || error == -EAGAIN) {
pci_dbg(pci_dev, "can't suspend now (%ps returned %d)\n",
pm->runtime_suspend, error);
return error;
} else if (error) {
pci_err(pci_dev, "can't suspend (%ps returned %d)\n",
pm->runtime_suspend, error);
return error;
}
}
pci_fixup_device(pci_fixup_suspend, pci_dev);
if (pm && pm->runtime_suspend
&& !pci_dev->state_saved && pci_dev->current_state != PCI_D0
&& pci_dev->current_state != PCI_UNKNOWN) {
pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
"PCI PM: State of device not saved by %pS\n",
pm->runtime_suspend);
return 0;
}
if (!pci_dev->state_saved) {
pci_save_state(pci_dev);
pci_finish_runtime_suspend(pci_dev);
}
return 0;
}
static int pci_pm_runtime_resume(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
pci_power_t prev_state = pci_dev->current_state;
int error = 0;
/*
* Restoring config space is necessary even if the device is not bound
* to a driver because although we left it in D0, it may have gone to
* D3cold when the bridge above it runtime suspended.
*/
pci_pm_default_resume_early(pci_dev);
pci_resume_ptm(pci_dev);
if (!pci_dev->driver)
return 0;
pci_fixup_device(pci_fixup_resume_early, pci_dev);
pci_pm_default_resume(pci_dev);
if (prev_state == PCI_D3cold)
pci_pm_bridge_power_up_actions(pci_dev);
if (pm && pm->runtime_resume)
error = pm->runtime_resume(dev);
return error;
}
static int pci_pm_runtime_idle(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
/*
* If pci_dev->driver is not set (unbound), the device should
* always remain in D0 regardless of the runtime PM status
*/
if (!pci_dev->driver)
return 0;
if (!pm)
return -ENOSYS;
if (pm->runtime_idle)
return pm->runtime_idle(dev);
return 0;
}
static const struct dev_pm_ops pci_dev_pm_ops = {
.prepare = pci_pm_prepare,
.complete = pci_pm_complete,
.suspend = pci_pm_suspend,
.suspend_late = pci_pm_suspend_late,
.resume = pci_pm_resume,
.resume_early = pci_pm_resume_early,
.freeze = pci_pm_freeze,
.thaw = pci_pm_thaw,
.poweroff = pci_pm_poweroff,
.poweroff_late = pci_pm_poweroff_late,
.restore = pci_pm_restore,
.suspend_noirq = pci_pm_suspend_noirq,
.resume_noirq = pci_pm_resume_noirq,
.freeze_noirq = pci_pm_freeze_noirq,
.thaw_noirq = pci_pm_thaw_noirq,
.poweroff_noirq = pci_pm_poweroff_noirq,
.restore_noirq = pci_pm_restore_noirq,
.runtime_suspend = pci_pm_runtime_suspend,
.runtime_resume = pci_pm_runtime_resume,
.runtime_idle = pci_pm_runtime_idle,
};
#define PCI_PM_OPS_PTR (&pci_dev_pm_ops)
#else /* !CONFIG_PM */
#define pci_pm_runtime_suspend NULL
#define pci_pm_runtime_resume NULL
#define pci_pm_runtime_idle NULL
#define PCI_PM_OPS_PTR NULL
#endif /* !CONFIG_PM */
/**
* __pci_register_driver - register a new pci driver
* @drv: the driver structure to register
* @owner: owner module of drv
* @mod_name: module name string
*
* Adds the driver structure to the list of registered drivers.
* Returns a negative value on error, otherwise 0.
* If no error occurred, the driver remains registered even if
* no device was claimed during registration.
*/
int __pci_register_driver(struct pci_driver *drv, struct module *owner,
const char *mod_name)
{
/* initialize common driver fields */
drv->driver.name = drv->name;
drv->driver.bus = &pci_bus_type;
drv->driver.owner = owner;
drv->driver.mod_name = mod_name;
drv->driver.groups = drv->groups;
drv->driver.dev_groups = drv->dev_groups;
spin_lock_init(&drv->dynids.lock);
INIT_LIST_HEAD(&drv->dynids.list);
/* register with core */
return driver_register(&drv->driver);
}
EXPORT_SYMBOL(__pci_register_driver);
/**
* pci_unregister_driver - unregister a pci driver
* @drv: the driver structure to unregister
*
* Deletes the driver structure from the list of registered PCI drivers,
* gives it a chance to clean up by calling its remove() function for
* each device it was responsible for, and marks those devices as
* driverless.
*/
void pci_unregister_driver(struct pci_driver *drv)
{
driver_unregister(&drv->driver);
pci_free_dynids(drv);
}
EXPORT_SYMBOL(pci_unregister_driver);
static struct pci_driver pci_compat_driver = {
.name = "compat"
};
/**
* pci_dev_driver - get the pci_driver of a device
* @dev: the device to query
*
* Returns the appropriate pci_driver structure or %NULL if there is no
* registered driver for the device.
*/
struct pci_driver *pci_dev_driver(const struct pci_dev *dev)
{
if (dev->driver)
return dev->driver;
else {
int i;
for (i = 0; i <= PCI_ROM_RESOURCE; i++)
if (dev->resource[i].flags & IORESOURCE_BUSY)
return &pci_compat_driver;
}
return NULL;
}
EXPORT_SYMBOL(pci_dev_driver);
/**
* pci_bus_match - Tell if a PCI device structure has a matching PCI device id structure
* @dev: the PCI device structure to match against
* @drv: the device driver to search for matching PCI device id structures
*
* Used by a driver to check whether a PCI device present in the
* system is in its list of supported devices. Returns the matching
* pci_device_id structure or %NULL if there is no match.
*/
static int pci_bus_match(struct device *dev, struct device_driver *drv)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
struct pci_driver *pci_drv;
const struct pci_device_id *found_id;
if (!pci_dev->match_driver)
return 0;
pci_drv = to_pci_driver(drv);
found_id = pci_match_device(pci_drv, pci_dev);
if (found_id)
return 1;
return 0;
}
/**
* pci_dev_get - increments the reference count of the pci device structure
* @dev: the device being referenced
*
* Each live reference to a device should be refcounted.
*
* Drivers for PCI devices should normally record such references in
* their probe() methods, when they bind to a device, and release
* them by calling pci_dev_put(), in their disconnect() methods.
*
* A pointer to the device with the incremented reference counter is returned.
*/
struct pci_dev *pci_dev_get(struct pci_dev *dev)
{
if (dev)
get_device(&dev->dev);
return dev;
}
EXPORT_SYMBOL(pci_dev_get);
/**
* pci_dev_put - release a use of the pci device structure
* @dev: device that's been disconnected
*
* Must be called when a user of a device is finished with it. When the last
* user of the device calls this function, the memory of the device is freed.
*/
void pci_dev_put(struct pci_dev *dev)
{
if (dev)
put_device(&dev->dev);
}
EXPORT_SYMBOL(pci_dev_put);
static int pci_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct pci_dev *pdev;
if (!dev)
return -ENODEV;
pdev = to_pci_dev(dev);
if (add_uevent_var(env, "PCI_CLASS=%04X", pdev->class))
return -ENOMEM;
if (add_uevent_var(env, "PCI_ID=%04X:%04X", pdev->vendor, pdev->device))
return -ENOMEM;
if (add_uevent_var(env, "PCI_SUBSYS_ID=%04X:%04X", pdev->subsystem_vendor,
pdev->subsystem_device))
return -ENOMEM;
if (add_uevent_var(env, "PCI_SLOT_NAME=%s", pci_name(pdev)))
return -ENOMEM;
if (add_uevent_var(env, "MODALIAS=pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02X",
pdev->vendor, pdev->device,
pdev->subsystem_vendor, pdev->subsystem_device,
(u8)(pdev->class >> 16), (u8)(pdev->class >> 8),
(u8)(pdev->class)))
return -ENOMEM;
return 0;
}
#if defined(CONFIG_PCIEAER) || defined(CONFIG_EEH)
/**
* pci_uevent_ers - emit a uevent during recovery path of PCI device
* @pdev: PCI device undergoing error recovery
* @err_type: type of error event
*/
void pci_uevent_ers(struct pci_dev *pdev, enum pci_ers_result err_type)
{
int idx = 0;
char *envp[3];
switch (err_type) {
case PCI_ERS_RESULT_NONE:
case PCI_ERS_RESULT_CAN_RECOVER:
envp[idx++] = "ERROR_EVENT=BEGIN_RECOVERY";
envp[idx++] = "DEVICE_ONLINE=0";
break;
case PCI_ERS_RESULT_RECOVERED:
envp[idx++] = "ERROR_EVENT=SUCCESSFUL_RECOVERY";
envp[idx++] = "DEVICE_ONLINE=1";
break;
case PCI_ERS_RESULT_DISCONNECT:
envp[idx++] = "ERROR_EVENT=FAILED_RECOVERY";
envp[idx++] = "DEVICE_ONLINE=0";
break;
default:
break;
}
if (idx > 0) {
envp[idx++] = NULL;
kobject_uevent_env(&pdev->dev.kobj, KOBJ_CHANGE, envp);
}
}
#endif
static int pci_bus_num_vf(struct device *dev)
{
return pci_num_vf(to_pci_dev(dev));
}
/**
* pci_dma_configure - Setup DMA configuration
* @dev: ptr to dev structure
*
* Function to update PCI devices's DMA configuration using the same
* info from the OF node or ACPI node of host bridge's parent (if any).
*/
static int pci_dma_configure(struct device *dev)
{
struct pci_driver *driver = to_pci_driver(dev->driver);
struct device *bridge;
int ret = 0;
bridge = pci_get_host_bridge_device(to_pci_dev(dev));
if (IS_ENABLED(CONFIG_OF) && bridge->parent &&
bridge->parent->of_node) {
ret = of_dma_configure(dev, bridge->parent->of_node, true);
} else if (has_acpi_companion(bridge)) {
struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);
ret = acpi_dma_configure(dev, acpi_get_dma_attr(adev));
}
pci_put_host_bridge_device(bridge);
if (!ret && !driver->driver_managed_dma) {
ret = iommu_device_use_default_domain(dev);
if (ret)
arch_teardown_dma_ops(dev);
}
return ret;
}
static void pci_dma_cleanup(struct device *dev)
{
struct pci_driver *driver = to_pci_driver(dev->driver);
if (!driver->driver_managed_dma)
iommu_device_unuse_default_domain(dev);
}
struct bus_type pci_bus_type = {
.name = "pci",
.match = pci_bus_match,
.uevent = pci_uevent,
.probe = pci_device_probe,
.remove = pci_device_remove,
.shutdown = pci_device_shutdown,
.dev_groups = pci_dev_groups,
.bus_groups = pci_bus_groups,
.drv_groups = pci_drv_groups,
.pm = PCI_PM_OPS_PTR,
.num_vf = pci_bus_num_vf,
.dma_configure = pci_dma_configure,
.dma_cleanup = pci_dma_cleanup,
};
EXPORT_SYMBOL(pci_bus_type);
#ifdef CONFIG_PCIEPORTBUS
static int pcie_port_bus_match(struct device *dev, struct device_driver *drv)
{
struct pcie_device *pciedev;
struct pcie_port_service_driver *driver;
if (drv->bus != &pcie_port_bus_type || dev->bus != &pcie_port_bus_type)
return 0;
pciedev = to_pcie_device(dev);
driver = to_service_driver(drv);
if (driver->service != pciedev->service)
return 0;
if (driver->port_type != PCIE_ANY_PORT &&
driver->port_type != pci_pcie_type(pciedev->port))
return 0;
return 1;
}
struct bus_type pcie_port_bus_type = {
.name = "pci_express",
.match = pcie_port_bus_match,
};
EXPORT_SYMBOL_GPL(pcie_port_bus_type);
#endif
static int __init pci_driver_init(void)
{
int ret;
ret = bus_register(&pci_bus_type);
if (ret)
return ret;
#ifdef CONFIG_PCIEPORTBUS
ret = bus_register(&pcie_port_bus_type);
if (ret)
return ret;
#endif
dma_debug_add_bus(&pci_bus_type);
return 0;
}
postcore_initcall(pci_driver_init);