v4.19.13 snapshot.
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
new file mode 100644
index 0000000..bef17c3
--- /dev/null
+++ b/drivers/pci/pci-driver.c
@@ -0,0 +1,1674 @@
+// 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/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 "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);
+}
+
+/**
+ * store_new_id - 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_id(pdrv->id_table, 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);
+
+/**
+ * store_remove_id - 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);
+
+/**
+ * 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 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.
+ *
+ * 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 - Tell if a PCI device structure has a matching PCI device id structure
+ * @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 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 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;
+
+ /* 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)
+ found_id = pci_match_id(drv->id_table, dev);
+
+ /* driver_override will always match, send a dummy id */
+ if (!found_id && dev->driver_override)
+ found_id = &pci_device_id_any;
+
+ return found_id;
+}
+
+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.
+ */
+ dev_warn(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
+ cpu = cpumask_any_and(cpumask_of_node(node), cpu_online_mask);
+
+ if (cpu < nr_cpu_ids)
+ error = work_on_cpu(cpu, local_pci_probe, &ddi);
+ else
+ error = local_pci_probe(&ddi);
+
+ 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 (!pci_dev->driver && 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);
+}
+#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);
+
+ pci_assign_irq(pci_dev);
+
+ error = pcibios_alloc_irq(pci_dev);
+ if (error < 0)
+ return error;
+
+ pci_dev_get(pci_dev);
+ if (pci_device_can_probe(pci_dev)) {
+ error = __pci_device_probe(drv, pci_dev);
+ if (error) {
+ pcibios_free_irq(pci_dev);
+ pci_dev_put(pci_dev);
+ }
+ }
+
+ return error;
+}
+
+static int pci_device_remove(struct device *dev)
+{
+ struct pci_dev *pci_dev = to_pci_dev(dev);
+ struct pci_driver *drv = pci_dev->driver;
+
+ if (drv) {
+ 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);
+ return 0;
+}
+
+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
+
+/* Auxiliary functions used for system resume and run-time 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
+
+#ifdef CONFIG_PM_SLEEP
+
+static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
+{
+ pci_power_up(pci_dev);
+ pci_restore_state(pci_dev);
+ pci_pme_restore(pci_dev);
+ pci_fixup_device(pci_fixup_resume_early, pci_dev);
+}
+
+/*
+ * 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, reenable */
+ 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(drv->suspend, error);
+ if (error)
+ return error;
+
+ if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
+ && pci_dev->current_state != PCI_UNKNOWN) {
+ WARN_ONCE(pci_dev->current_state != prev,
+ "PCI PM: Device state not saved by %pF\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);
+ struct pci_driver *drv = pci_dev->driver;
+
+ if (drv && drv->suspend_late) {
+ pci_power_t prev = pci_dev->current_state;
+ int error;
+
+ error = drv->suspend_late(pci_dev, state);
+ suspend_report_result(drv->suspend_late, error);
+ if (error)
+ return error;
+
+ if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
+ && pci_dev->current_state != PCI_UNKNOWN) {
+ WARN_ONCE(pci_dev->current_state != prev,
+ "PCI PM: Device state not saved by %pF\n",
+ drv->suspend_late);
+ goto Fixup;
+ }
+ }
+
+ if (!pci_dev->state_saved)
+ pci_save_state(pci_dev);
+
+ pci_pm_set_unknown_state(pci_dev);
+
+Fixup:
+ pci_fixup_device(pci_fixup_suspend_late, pci_dev);
+
+ return 0;
+}
+
+static int pci_legacy_resume_early(struct device *dev)
+{
+ struct pci_dev *pci_dev = to_pci_dev(dev);
+ struct pci_driver *drv = pci_dev->driver;
+
+ return drv && drv->resume_early ?
+ drv->resume_early(pci_dev) : 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_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_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->suspend_late || drv->resume
+ || drv->resume_early);
+
+ /*
+ * 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.
+ */
+ WARN(ret && drv->driver.pm, "driver %s device %04x:%04x\n",
+ drv->name, pci_dev->vendor, pci_dev->device);
+
+ return ret;
+}
+
+/* New power management framework */
+
+static int pci_pm_prepare(struct device *dev)
+{
+ struct device_driver *drv = dev->driver;
+
+ if (drv && drv->pm && drv->pm->prepare) {
+ int error = drv->pm->prepare(dev);
+ if (error < 0)
+ return error;
+
+ if (!error && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
+ return 0;
+ }
+ return pci_dev_keep_suspended(to_pci_dev(dev));
+}
+
+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_update_current_state(pci_dev, pci_dev->current_state);
+ 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;
+
+ 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_keep_suspended(pci_dev)) {
+ pm_runtime_resume(dev);
+ pci_dev->state_saved = false;
+ }
+
+ if (pm->suspend) {
+ pci_power_t prev = pci_dev->current_state;
+ int error;
+
+ error = pm->suspend(dev);
+ suspend_report_result(pm->suspend, error);
+ if (error)
+ return error;
+
+ if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
+ && pci_dev->current_state != PCI_UNKNOWN) {
+ WARN_ONCE(pci_dev->current_state != prev,
+ "PCI PM: State of device not saved by %pF\n",
+ pm->suspend);
+ }
+ }
+
+ return 0;
+}
+
+static int pci_pm_suspend_late(struct device *dev)
+{
+ if (dev_pm_smart_suspend_and_suspended(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_smart_suspend_and_suspended(dev)) {
+ dev->power.may_skip_resume = true;
+ 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(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) {
+ WARN_ONCE(pci_dev->current_state != prev,
+ "PCI PM: State of device not saved by %pF\n",
+ pm->suspend_noirq);
+ goto Fixup;
+ }
+ }
+
+ if (!pci_dev->state_saved) {
+ pci_save_state(pci_dev);
+ if (pci_power_manageable(pci_dev))
+ pci_prepare_to_sleep(pci_dev);
+ }
+
+ dev_dbg(dev, "PCI PM: Suspend power state: %s\n",
+ pci_power_name(pci_dev->current_state));
+
+ 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.
+ */
+ dev->power.may_skip_resume = device_may_wakeup(dev) ||
+ !device_can_wakeup(dev);
+
+ return 0;
+}
+
+static int pci_pm_resume_noirq(struct device *dev)
+{
+ struct pci_dev *pci_dev = to_pci_dev(dev);
+ struct device_driver *drv = dev->driver;
+ int error = 0;
+
+ if (dev_pm_may_skip_resume(dev))
+ return 0;
+
+ /*
+ * Devices with DPM_FLAG_SMART_SUSPEND may be left in runtime suspend
+ * during system suspend, so update their runtime PM status to "active"
+ * as they are going to be put into D0 shortly.
+ */
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ pm_runtime_set_active(dev);
+
+ pci_pm_default_resume_early(pci_dev);
+
+ if (pci_has_legacy_pm_support(pci_dev))
+ return pci_legacy_resume_early(dev);
+
+ pcie_pme_root_status_cleanup(pci_dev);
+
+ if (drv && drv->pm && drv->pm->resume_noirq)
+ error = drv->pm->resume_noirq(dev);
+
+ return error;
+}
+
+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;
+ int error = 0;
+
+ /*
+ * 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);
+
+ if (pci_has_legacy_pm_support(pci_dev))
+ return pci_legacy_resume(dev);
+
+ pci_pm_default_resume(pci_dev);
+
+ if (pm) {
+ if (pm->resume)
+ error = pm->resume(dev);
+ } else {
+ pci_pm_reenable_device(pci_dev);
+ }
+
+ return error;
+}
+
+#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_noirq NULL
+
+#endif /* !CONFIG_SUSPEND */
+
+#ifdef CONFIG_HIBERNATE_CALLBACKS
+
+
+/*
+ * pcibios_pm_ops - provide arch-specific hooks when a PCI device is doing
+ * a hibernate transition
+ */
+struct dev_pm_ops __weak pcibios_pm_ops;
+
+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;
+ }
+
+ /*
+ * This used to be done in pci_pm_prepare() for all devices and some
+ * drivers may depend on it, so do it here. Ideally, runtime-suspended
+ * devices should not be touched during freeze/thaw transitions,
+ * however.
+ */
+ if (!dev_pm_smart_suspend_and_suspended(dev)) {
+ pm_runtime_resume(dev);
+ pci_dev->state_saved = false;
+ }
+
+ if (pm->freeze) {
+ int error;
+
+ error = pm->freeze(dev);
+ suspend_report_result(pm->freeze, error);
+ if (error)
+ return error;
+ }
+
+ return 0;
+}
+
+static int pci_pm_freeze_late(struct device *dev)
+{
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ return 0;
+
+ return pm_generic_freeze_late(dev);
+}
+
+static int pci_pm_freeze_noirq(struct device *dev)
+{
+ struct pci_dev *pci_dev = to_pci_dev(dev);
+ struct device_driver *drv = dev->driver;
+
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ return 0;
+
+ if (pci_has_legacy_pm_support(pci_dev))
+ return pci_legacy_suspend_late(dev, PMSG_FREEZE);
+
+ if (drv && drv->pm && drv->pm->freeze_noirq) {
+ int error;
+
+ error = drv->pm->freeze_noirq(dev);
+ suspend_report_result(drv->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);
+
+ if (pcibios_pm_ops.freeze_noirq)
+ return pcibios_pm_ops.freeze_noirq(dev);
+
+ return 0;
+}
+
+static int pci_pm_thaw_noirq(struct device *dev)
+{
+ struct pci_dev *pci_dev = to_pci_dev(dev);
+ struct device_driver *drv = dev->driver;
+ int error = 0;
+
+ /*
+ * If the device is in runtime suspend, the code below may not work
+ * correctly with it, so skip that code and make the PM core skip all of
+ * the subsequent "thaw" callbacks for the device.
+ */
+ if (dev_pm_smart_suspend_and_suspended(dev)) {
+ dev_pm_skip_next_resume_phases(dev);
+ return 0;
+ }
+
+ if (pcibios_pm_ops.thaw_noirq) {
+ error = pcibios_pm_ops.thaw_noirq(dev);
+ if (error)
+ return error;
+ }
+
+ if (pci_has_legacy_pm_support(pci_dev))
+ return pci_legacy_resume_early(dev);
+
+ /*
+ * pci_restore_state() requires the device to be in D0 (because of MSI
+ * restoration among other things), so force it into D0 in case the
+ * driver's "freeze" callbacks put it into a low-power state directly.
+ */
+ pci_set_power_state(pci_dev, PCI_D0);
+ pci_restore_state(pci_dev);
+
+ if (drv && drv->pm && drv->pm->thaw_noirq)
+ error = drv->pm->thaw_noirq(dev);
+
+ return error;
+}
+
+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_keep_suspended(pci_dev))
+ pm_runtime_resume(dev);
+
+ pci_dev->state_saved = false;
+ if (pm->poweroff) {
+ int error;
+
+ error = pm->poweroff(dev);
+ suspend_report_result(pm->poweroff, error);
+ if (error)
+ return error;
+ }
+
+ return 0;
+}
+
+static int pci_pm_poweroff_late(struct device *dev)
+{
+ if (dev_pm_smart_suspend_and_suspended(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);
+ struct device_driver *drv = dev->driver;
+
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ return 0;
+
+ if (pci_has_legacy_pm_support(to_pci_dev(dev)))
+ return pci_legacy_suspend_late(dev, PMSG_HIBERNATE);
+
+ if (!drv || !drv->pm) {
+ pci_fixup_device(pci_fixup_suspend_late, pci_dev);
+ return 0;
+ }
+
+ if (drv->pm->poweroff_noirq) {
+ int error;
+
+ error = drv->pm->poweroff_noirq(dev);
+ suspend_report_result(drv->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);
+
+ if (pcibios_pm_ops.poweroff_noirq)
+ return pcibios_pm_ops.poweroff_noirq(dev);
+
+ return 0;
+}
+
+static int pci_pm_restore_noirq(struct device *dev)
+{
+ struct pci_dev *pci_dev = to_pci_dev(dev);
+ struct device_driver *drv = dev->driver;
+ int error = 0;
+
+ /* This is analogous to the pci_pm_resume_noirq() case. */
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ pm_runtime_set_active(dev);
+
+ if (pcibios_pm_ops.restore_noirq) {
+ error = pcibios_pm_ops.restore_noirq(dev);
+ if (error)
+ return error;
+ }
+
+ pci_pm_default_resume_early(pci_dev);
+
+ if (pci_has_legacy_pm_support(pci_dev))
+ return pci_legacy_resume_early(dev);
+
+ if (drv && drv->pm && drv->pm->restore_noirq)
+ error = drv->pm->restore_noirq(dev);
+
+ return error;
+}
+
+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;
+ int error = 0;
+
+ /*
+ * 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)
+ error = pm->restore(dev);
+ } else {
+ pci_pm_reenable_device(pci_dev);
+ }
+
+ return error;
+}
+
+#else /* !CONFIG_HIBERNATE_CALLBACKS */
+
+#define pci_pm_freeze NULL
+#define pci_pm_freeze_late 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;
+
+ /*
+ * 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;
+ }
+
+ if (!pm || !pm->runtime_suspend)
+ return -ENOSYS;
+
+ pci_dev->state_saved = false;
+ error = pm->runtime_suspend(dev);
+ if (error) {
+ /*
+ * -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)
+ dev_dbg(dev, "can't suspend now (%pf returned %d)\n",
+ pm->runtime_suspend, error);
+ else
+ dev_err(dev, "can't suspend (%pf returned %d)\n",
+ pm->runtime_suspend, error);
+
+ return error;
+ }
+
+ pci_fixup_device(pci_fixup_suspend, pci_dev);
+
+ if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
+ && pci_dev->current_state != PCI_UNKNOWN) {
+ WARN_ONCE(pci_dev->current_state != prev,
+ "PCI PM: State of device not saved by %pF\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)
+{
+ int rc;
+ struct pci_dev *pci_dev = to_pci_dev(dev);
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+
+ /*
+ * 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_restore_standard_config(pci_dev);
+
+ if (!pci_dev->driver)
+ return 0;
+
+ if (!pm || !pm->runtime_resume)
+ return -ENOSYS;
+
+ pci_fixup_device(pci_fixup_resume_early, pci_dev);
+ pci_enable_wake(pci_dev, PCI_D0, false);
+ pci_fixup_device(pci_fixup_resume, pci_dev);
+
+ rc = pm->runtime_resume(dev);
+
+ pci_dev->runtime_d3cold = false;
+
+ return rc;
+}
+
+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;
+ int ret = 0;
+
+ /*
+ * 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)
+ ret = pm->runtime_idle(dev);
+
+ return ret;
+}
+
+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,
+ .freeze = pci_pm_freeze,
+ .freeze_late = pci_pm_freeze_late,
+ .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;
+
+ 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_PCIEPORTBUS) || 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 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);
+ enum dev_dma_attr attr = acpi_get_dma_attr(adev);
+
+ if (attr != DEV_DMA_NOT_SUPPORTED)
+ ret = acpi_dma_configure(dev, attr);
+ }
+
+ pci_put_host_bridge_device(bridge);
+ return ret;
+}
+
+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,
+};
+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);