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pci-driver.c
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/*
* drivers/pci/pci-driver.c
*
* (C) Copyright 2002-2004, 2007 Greg Kroah-Hartman <[email protected]>
* (C) Copyright 2007 Novell Inc.
*
* Released under the GPL v2 only.
*
*/
#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 "pci.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 store_new_id(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(new_id, S_IWUSR, NULL, store_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 store_remove_id(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;
int 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 = 0;
break;
}
}
spin_unlock(&pdrv->dynids.lock);
if (retval)
return retval;
return count;
}
static DRIVER_ATTR(remove_id, S_IWUSR, NULL, store_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()
* 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 int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
const struct pci_device_id *id)
{
int error, node;
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);
/*
* On NUMA systems, we are likely to call a PF probe function using
* work_on_cpu(). If that probe calls pci_enable_sriov() (which
* adds the VF devices via pci_bus_add_device()), we may re-enter
* this function to call the VF probe function. Calling
* work_on_cpu() again will cause a lockdep warning. Since VFs are
* always on the same node as the PF, we can work around this by
* avoiding work_on_cpu() when we're already on the correct node.
*
* Preemption is enabled, so it's theoretically unsafe to use
* numa_node_id(), but even if we run the probe function on the
* wrong node, it should be functionally correct.
*/
if (node >= 0 && node != numa_node_id()) {
int cpu;
get_online_cpus();
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);
put_online_cpus();
} else
error = local_pci_probe(&ddi);
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);
if (error >= 0)
error = 0;
}
return error;
}
static int pci_device_probe(struct device *dev)
{
int error = 0;
struct pci_driver *drv;
struct pci_dev *pci_dev;
drv = to_pci_driver(dev->driver);
pci_dev = to_pci_dev(dev);
pci_dev_get(pci_dev);
error = __pci_device_probe(drv, pci_dev);
if (error)
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);
}
pci_dev->driver = NULL;
}
/* 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);
pci_msi_shutdown(pci_dev);
pci_msix_shutdown(pci_dev);
#ifdef CONFIG_KEXEC
/*
* 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);
#endif
}
#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);
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_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);
if (!pci_has_subordinate(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;
/*
* Devices having power.ignore_children set may still be necessary for
* suspending their children in the next phase of device suspend.
*/
if (dev->power.ignore_children)
pm_runtime_resume(dev);
if (drv && drv->pm && drv->pm->prepare) {
int error = drv->pm->prepare(dev);
if (error)
return error;
}
return pci_dev_keep_suspended(to_pci_dev(dev));
}
#else /* !CONFIG_PM_SLEEP */
#define pci_pm_prepare NULL
#endif /* !CONFIG_PM_SLEEP */
#ifdef CONFIG_SUSPEND
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);
goto Fixup;
}
/*
* PCI devices suspended at run time need to be resumed at this point,
* because in general it is necessary to reconfigure them for system
* suspend. Namely, if the device is supposed to wake up the system
* from the sleep state, we may need to reconfigure it for this purpose.
* In turn, if the device is not supposed to wake up the system from the
* sleep state, we'll have to prevent it from signaling wake-up.
*/
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);
}
}
Fixup:
pci_fixup_device(pci_fixup_suspend, pci_dev);
return 0;
}
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 (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_has_subordinate(pci_dev))
pci_prepare_to_sleep(pci_dev);
}
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);
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;
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->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_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.
*/
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;
}
if (pcibios_pm_ops.freeze)
return pcibios_pm_ops.freeze(dev);
return 0;
}
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 (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 (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_update_current_state(pci_dev, PCI_D0);
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 (pcibios_pm_ops.thaw) {
error = pcibios_pm_ops.thaw(dev);
if (error)
return error;
}
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);
goto Fixup;
}
/* The reason to do that is the same as in pci_pm_suspend(). */
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;
}
Fixup:
pci_fixup_device(pci_fixup_suspend, pci_dev);
if (pcibios_pm_ops.poweroff)
return pcibios_pm_ops.poweroff(dev);
return 0;
}
static int pci_pm_poweroff_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);