linux-toradex.git/drivers/pci/pci-driver.c, branch v3.0.2

PCI / PM: Block races between runtime PM and system sleep

2011-06-21T21:47:15+00:00

After commit e8665002477f0278f84f898145b1f141ba26ee26
(PM: Allow pm_runtime_suspend() to succeed during system suspend) it
is possible that a device resumed by the pm_runtime_resume(dev) in
pci_pm_prepare() will be suspended immediately from a work item,
timer function or otherwise, defeating the very purpose of calling
pm_runtime_resume(dev) from there.  To prevent that from happening
it is necessary to increment the runtime PM usage counter of the
device by replacing pm_runtime_resume() with pm_runtime_get_sync().
Moreover, the incremented runtime PM usage counter has to be
decremented by the corresponding pci_pm_complete(), via
pm_runtime_put_sync().

Signed-off-by: Rafael J. Wysocki 
Cc: stable@kernel.org
Acked-by: Jesse Barnes

PM / Hibernate: Introduce CONFIG_HIBERNATE_CALLBACKS

2011-04-11T20:54:42+00:00

Xen save/restore is going to use hibernate device callbacks for
quiescing devices and putting them back to normal operations and it
would need to select CONFIG_HIBERNATION for this purpose.  However,
that also would cause the hibernate interfaces for user space to be
enabled, which might confuse user space, because the Xen kernels
don't support hibernation.  Moreover, it would be wasteful, as it
would make the Xen kernels include a substantial amount of code that
they would never use.

To address this issue introduce new power management Kconfig option
CONFIG_HIBERNATE_CALLBACKS, such that it will only select the code
that is necessary for the hibernate device callbacks to work and make
CONFIG_HIBERNATION select it.  Then, Xen save/restore will be able to
select CONFIG_HIBERNATE_CALLBACKS without dragging the entire
hibernate code along with it.

Signed-off-by: Rafael J. Wysocki 
Tested-by: Shriram Rajagopalan

PM: Remove CONFIG_PM_OPS

2011-03-14T23:43:15+00:00

After redefining CONFIG_PM to depend on (CONFIG_PM_SLEEP ||
CONFIG_PM_RUNTIME) the CONFIG_PM_OPS option is redundant and can be
replaced with CONFIG_PM.

Signed-off-by: Rafael J. Wysocki

PCI: fix __pci_device_probe kernel-doc warning

2010-12-23T20:53:09+00:00

Fix kernel-doc warning for __pci_device_probe():

Warning(drivers/pci/pci-driver.c:341): missing initial short description on line:
 * __pci_device_probe()

Signed-off-by: Randy Dunlap 
Signed-off-by: Jesse Barnes

PCI: make pci_restore_state return void

2010-12-23T20:53:09+00:00

pci_restore_state only ever returns 0, thus there is no benefit in
having it return any value.  Also, a large majority of the callers do
not check the return code of pci_restore_state.  Make the
pci_restore_state a void return and avoid the overhead.

Acked-by: Mauro Carvalho Chehab 
Signed-off-by: Jon Mason 
Signed-off-by: Jesse Barnes

PCI: change device runtime PM settings for probe and remove

2010-07-30T16:29:09+00:00

This patch (as1388) changes the way the PCI core handles runtime PM
settings when probing or unbinding drivers.  Now the core will make
sure the device is enabled for runtime PM, with a usage count >= 1,
when a driver is probed.  It does the same when calling a driver's
remove method.

If the driver wants to use runtime PM, all it has to do is call
pm_runtime_pu_noidle() near the end of its probe routine (to cancel
the core's usage increment) and pm_runtime_get_noresume() near the
start of its remove routine (to restore the usage count).  It does not
need to mess around with setting the runtime state to enabled,
disabled, active, or suspended.

The patch updates e1000e and r8169, the only PCI drivers that already
use the existing runtime PM interface.

Signed-off-by: Alan Stern 
Acked-by: Rafael J. Wysocki 
Signed-off-by: Jesse Barnes

PCI PM: Run-time callbacks for PCI bus type

2010-02-23T00:21:19+00:00

Introduce run-time PM callbacks for the PCI bus type.  Make the new
callbacks work in analogy with the existing system sleep PM
callbacks, so that the drivers already converted to struct dev_pm_ops
can use their suspend and resume routines for run-time PM without
modifications.

Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Jesse Barnes

Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6

2009-09-16T14:49:54+00:00

* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (75 commits)
  PCI hotplug: clean up acpi_run_hpp()
  PCI hotplug: acpiphp: use generic pci_configure_slot()
  PCI hotplug: shpchp: use generic pci_configure_slot()
  PCI hotplug: pciehp: use generic pci_configure_slot()
  PCI hotplug: add pci_configure_slot()
  PCI hotplug: clean up acpi_get_hp_params_from_firmware() interface
  PCI hotplug: acpiphp: don't cache hotplug_params in acpiphp_bridge
  PCI hotplug: acpiphp: remove superfluous _HPP/_HPX evaluation
  PCI: Clear saved_state after the state has been restored
  PCI PM: Return error codes from pci_pm_resume()
  PCI: use dev_printk in quirk messages
  PCI / PCIe portdrv: Fix pcie_portdrv_slot_reset()
  PCI Hotplug: convert acpi_pci_detect_ejectable() to take an acpi_handle
  PCI Hotplug: acpiphp: find bridges the easy way
  PCI: pcie portdrv: remove unused variable
  PCI / ACPI PM: Propagate wake-up enable for devices w/o ACPI support
  ACPI PM: Replace wakeup.prepared with reference counter
  PCI PM: Introduce device flag wakeup_prepared
  PCI / ACPI PM: Rework some debug messages
  PCI PM: Simplify PCI wake-up code
  ...

Fixed up conflict in arch/powerpc/kernel/pci_64.c due to OF device tree
scanning having been moved and merged for the 32- and 64-bit cases.  The
'needs_freset' initialization added in 6e19314cc ("PCI/powerpc: support
PCIe fundamental reset") is now in arch/powerpc/kernel/pci_of_scan.c.

PCI: Clear saved_state after the state has been restored

2009-09-14T20:41:46+00:00

Some PCI devices fail if their standard configuration registers are
restored twice in a row.  Prevent this from happening by making
pci_restore_state() clear the saved_state flag of the device right
after the device's standard configuration registers have been
populated with the previously saved values.

Simplify PCI PM callbacks by removing the direct clearing of
state_saved from them, as it shouldn't be necessary any more (except
in pci_pm_thaw(), where it has to be cleared, so that the values saved
during the "freeze" phase of hibernation are not used later by mistake).

Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Jesse Barnes

PCI PM: Return error codes from pci_pm_resume()

2009-09-14T20:41:42+00:00

Currently pci_pm_resume() always returns 0, which makes the error
variable defined in there a bit pointless.  Make pci_pm_resume()
return error codes obtained from drivers' callbacks.

Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Jesse Barnes