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PCI/PM: Remove unused pci_driver.suspend_late() hook

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The struct pci_driver.suspend_late() hook is one of the legacy PCI power
management callbacks, and there are no remaining users of it.  Remove it.

Link: https://lore.kernel.org/r/20191101204558.210235-7-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Bjorn Helgaas 2019-10-31 17:37:54 -05:00
parent 89cdbc3546
commit 1a1daf097e
3 changed files with 6 additions and 28 deletions
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10
Documentation/power/pci.rst
View file

@ -692,11 +692,11 @@ controlling the runtime power management of their devices.
At the time of this writing there are two ways to define power management
callbacks for a PCI device driver, the recommended one, based on using a
dev_pm_ops structure described in Documentation/driver-api/pm/devices.rst, and
the "legacy" one, in which the .suspend(), .suspend_late(), and
.resume() callbacks from struct pci_driver are used. The legacy approach,
however, doesn't allow one to define runtime power management callbacks and is
not really suitable for any new drivers. Therefore it is not covered by this
document (refer to the source code to learn more about it).
the "legacy" one, in which the .suspend() and .resume() callbacks from struct
pci_driver are used. The legacy approach, however, doesn't allow one to define
runtime power management callbacks and is not really suitable for any new
drivers. Therefore it is not covered by this document (refer to the source code
to learn more about it).
It is recommended that all PCI device drivers define a struct dev_pm_ops object
containing pointers to power management (PM) callbacks that will be executed by

22
drivers/pci/pci-driver.c
View file

@ -599,32 +599,12 @@ static int pci_legacy_suspend(struct device *dev, pm_message_t state)
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) {
pci_WARN_ONCE(pci_dev, pci_dev->current_state != prev,
"PCI PM: Device state not saved by %pS\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;
@ -653,7 +633,7 @@ static void pci_pm_default_suspend(struct pci_dev *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);
bool ret = drv && (drv->suspend || drv->resume);
/*
* Legacy PM support is used by default, so warn if the new framework is

2
include/linux/pci.h
View file

@ -805,7 +805,6 @@ struct module;
* The remove function always gets called from process
* context, so it can sleep.
* @suspend: Put device into low power state.
* @suspend_late: Put device into low power state.
* @resume: Wake device from low power state.
* (Please see Documentation/power/pci.rst for descriptions
* of PCI Power Management and the related functions.)
@ -828,7 +827,6 @@ struct pci_driver {
int (*probe)(struct pci_dev *dev, const struct pci_device_id *id); /* New device inserted */
void (*remove)(struct pci_dev *dev); /* Device removed (NULL if not a hot-plug capable driver) */
int (*suspend)(struct pci_dev *dev, pm_message_t state); /* Device suspended */
int (*suspend_late)(struct pci_dev *dev, pm_message_t state);
int (*resume)(struct pci_dev *dev); /* Device woken up */
void (*shutdown)(struct pci_dev *dev);
int (*sriov_configure)(struct pci_dev *dev, int num_vfs); /* On PF */