Introduce user space interface for manipulating hotplug profiles
associated with ACPI scan handlers.
The interface consists of sysfs directories under
/sys/firmware/acpi/hotplug/, one for each hotplug profile, containing
an attribute allowing user space to manipulate the enabled field of
the corresponding profile. Namely, switching the enabled attribute
from '0' to '1' will cause the common hotplug notify handler to be
installed for all ACPI namespace objects representing devices matching
the scan handler associated with the given hotplug profile (and
analogously for the converse switch).
Drivers willing to use the new user space interface should add their
ACPI scan handlers with the help of new funtion
acpi_scan_add_handler_with_hotplug().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Tested-by: Toshi Kani <toshi.kani@hp.com>
Multiple drivers handling hotplug-capable ACPI device nodes install
notify handlers covering the same types of events in a very similar
way. Moreover, those handlers are installed in separate namespace
walks, although that really should be done during namespace scans
carried out by acpi_bus_scan(). This leads to substantial code
duplication, unnecessary overhead and behavior that is hard to
follow.
For this reason, introduce common code in drivers/acpi/scan.c for
handling hotplug-related notification and carrying out device
insertion and eject operations in a generic fashion, such that it
may be used by all of the relevant drivers in the future. To cover
the existing differences between those drivers introduce struct
acpi_hotplug_profile for representing collections of hotplug
settings associated with different ACPI scan handlers that can be
used by the drivers to make the common code reflect their current
behavior.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Tested-by: Toshi Kani <toshi.kani@hp.com>
Pull PCI changes from Bjorn Helgaas:
"Host bridge hotplug
- Major overhaul of ACPI host bridge add/start (Rafael Wysocki, Yinghai Lu)
- Major overhaul of PCI/ACPI binding (Rafael Wysocki, Yinghai Lu)
- Split out ACPI host bridge and ACPI PCI device hotplug (Yinghai Lu)
- Stop caching _PRT and make independent of bus numbers (Yinghai Lu)
PCI device hotplug
- Clean up cpqphp dead code (Sasha Levin)
- Disable ARI unless device and upstream bridge support it (Yijing Wang)
- Initialize all hot-added devices (not functions 0-7) (Yijing Wang)
Power management
- Don't touch ASPM if disabled (Joe Lawrence)
- Fix ASPM link state management (Myron Stowe)
Miscellaneous
- Fix PCI_EXP_FLAGS accessor (Alex Williamson)
- Disable Bus Master in pci_device_shutdown (Konstantin Khlebnikov)
- Document hotplug resource and MPS parameters (Yijing Wang)
- Add accessor for PCIe capabilities (Myron Stowe)
- Drop pciehp suspend/resume messages (Paul Bolle)
- Make pci_slot built-in only (not a module) (Jiang Liu)
- Remove unused PCI/ACPI bind ops (Jiang Liu)
- Removed used pci_root_bus (Bjorn Helgaas)"
* tag 'pci-v3.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (51 commits)
PCI/ACPI: Don't cache _PRT, and don't associate them with bus numbers
PCI: Fix PCI Express Capability accessors for PCI_EXP_FLAGS
ACPI / PCI: Make pci_slot built-in only, not a module
PCI/PM: Clear state_saved during suspend
PCI: Use atomic_inc_return() rather than atomic_add_return()
PCI: Catch attempts to disable already-disabled devices
PCI: Disable Bus Master unconditionally in pci_device_shutdown()
PCI: acpiphp: Remove dead code for PCI host bridge hotplug
PCI: acpiphp: Create companion ACPI devices before creating PCI devices
PCI: Remove unused "rc" in virtfn_add_bus()
PCI: pciehp: Drop suspend/resume ENTRY messages
PCI/ASPM: Don't touch ASPM if forcibly disabled
PCI/ASPM: Deallocate upstream link state even if device is not PCIe
PCI: Document MPS parameters pci=pcie_bus_safe, pci=pcie_bus_perf, etc
PCI: Document hpiosize= and hpmemsize= resource reservation parameters
PCI: Use PCI Express Capability accessor
PCI: Introduce accessor to retrieve PCIe Capabilities Register
PCI: Put pci_dev in device tree as early as possible
PCI: Skip attaching driver in device_add()
PCI: acpiphp: Keep driver loaded even if no slots found
...
This changeset is aimed at fixing a few different but related
problems in the ACPI hotplug infrastructure.
First of all, since notify handlers may be run in parallel with
acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device()
and some of them are installed for ACPI handles that have no struct
acpi_device objects attached (i.e. before those objects are created),
those notify handlers have to take acpi_scan_lock to prevent races
from taking place (e.g. a struct acpi_device is found to be present
for the given ACPI handle, but right after that it is removed by
acpi_bus_trim() running in parallel to the given notify handler).
Moreover, since some of them call acpi_bus_scan() and
acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock
should be acquired by the callers of these two funtions rather by
these functions themselves.
For these reasons, make all notify handlers that can handle device
addition and eject events take acpi_scan_lock and remove the
acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim().
Accordingly, update all of their users to make sure that they
are always called under acpi_scan_lock.
Furthermore, since eject operations are carried out asynchronously
with respect to the notify events that trigger them, with the help
of acpi_bus_hot_remove_device(), even if notify handlers take the
ACPI scan lock, it still is possible that, for example,
acpi_bus_trim() will run between acpi_bus_hot_remove_device() and
the notify handler that scheduled its execution and that
acpi_bus_trim() will remove the device node passed to
acpi_bus_hot_remove_device() for ejection. In that case, the struct
acpi_device object obtained by acpi_bus_hot_remove_device() will be
invalid and not-so-funny things will ensue. To protect agaist that,
make the users of acpi_bus_hot_remove_device() run get_device() on
ACPI device node objects that are about to be passed to it and make
acpi_bus_hot_remove_device() run put_device() on them and check if
their ACPI handles are not NULL (make acpi_device_unregister() clear
the device nodes' ACPI handles for that check to work).
Finally, observe that acpi_os_hotplug_execute() actually can fail,
in which case its caller ought to free memory allocated for the
context object to prevent leaks from happening. It also needs to
run put_device() on the device node that it ran get_device() on
previously in that case. Modify the code accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Introduce struct acpi_scan_handler for representing objects that
will do configuration tasks depending on ACPI device nodes'
hardware IDs (HIDs).
Currently, those tasks are done either directly by the ACPI namespace
scanning code or by ACPI device drivers designed specifically for
this purpose. None of the above is desirable, however, because
doing that directly in the namespace scanning code makes that code
overly complicated and difficult to follow and doing that in
"special" device drivers leads to a great deal of confusion about
their role and to confusing interactions with the driver core (for
example, sysfs directories are created for those drivers, but they
are completely unnecessary and only increase the kernel's memory
footprint in vain).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
* pci/yinghai-root-bus-hotplug:
PCI: Put pci_dev in device tree as early as possible
PCI: Skip attaching driver in device_add()
PCI: acpiphp: Keep driver loaded even if no slots found
PCI/ACPI: Print info if host bridge notify handler installation fails
PCI: acpiphp: Move host bridge hotplug to pci_root.c
PCI/ACPI: acpiphp: Rename alloc_acpiphp_hp_work() to alloc_acpi_hp_work()
PCI: Make device create/destroy logic symmetric
PCI: Fix reference count leak in pci_dev_present()
PCI: Set pci_dev dev_node early so IOAPIC irq_descs are allocated locally
PCI: Add root bus children dev's res to fail list
PCI: acpiphp: Add is_hotplug_bridge detection
Conflicts:
drivers/pci/pci.h
* pci/acpi-scan2:
ACPI / scan: Drop acpi_bus_add() and use acpi_bus_scan() instead
ACPI: update ej_event interface to take acpi_device
ACPI / scan: Add second pass to acpi_bus_trim()
ACPI / scan: Change the implementation of acpi_bus_trim()
ACPI / scan: Drop the second argument of acpi_bus_trim()
ACPI / scan: Drop the second argument of acpi_device_unregister()
ACPI: Remove the ops field from struct acpi_device
ACPI: remove unused acpi_op_bind and acpi_op_unbind
ACPI / scan: Fix check of device_attach() return value.
The second argument of ACPI driver .remove() operation is only used
by the ACPI processor driver and the value passed to that driver
through it is always available from the given struct acpi_device
object's removal_type field. For this reason, the second ACPI driver
.remove() argument is in fact useless, so drop it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Since ACPI power resources are going to be used more extensively on
new hardware platforms, it becomes necessary for user space (powertop
in particular) to observe some properties of those resources for
diagnostics purposes.
For this reason, expose the current status of each ACPI power
resource to user space via sysfs by adding a new resource_in_use
attribute to the sysfs directory representing the given power
resource.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move ACPI device power management functions from drivers/acpi/bus.c
to drivers/acpi/device_pm.c.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The only difference between acpi_bus_scan() and acpi_bus_add() is the
invocation of acpi_update_all_gpes() in the latter which in fact is
unnecessary, because acpi_update_all_gpes() has already been called
by acpi_scan_init() and the way it is implemented guarantees the next
invocations of it to do nothing.
For this reason, drop acpi_bus_add() and make all its callers use
acpi_bus_scan() directly instead of it. Additionally, rearrange the
code in acpi_scan_init() slightly to improve the visibility of the
acpi_update_all_gpes() call in there.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
The function returning string representations of ACPI device power
states, state_string((), is now static, because it is only used
internally in drivers/acpi/bus.c. However, it will be used outside
of that file going forward, so rename it to
acpi_power_state_string(), add a kerneldoc comment to it and add its
header to acpi_bus.h.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The function used for retrieving ACPI device power states,
__acpi_bus_get_power(), is now static, because it is only used
internally in drivers/acpi/bus.c. However, it will be used
outside of that file going forward, so rename it to
acpi_device_get_power(), in analogy with acpi_device_set_power(),
add a kerneldoc comment to it and add its header to acpi_bus.h.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI power resources have an order attribute that should be taken
into account when turning them on and off, but it is not used now.
Modify the power resources management code to preserve the
spec-compliant ordering of wakeup power resources.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI power resources have an order attribute that should be taken
into account when turning them on and off, but it is not used now.
Modify the power resources management code to preserve the
spec-compliant ordering of power resources that power states of
devices depend on (analogous changes will be done separately for
power resources used for wakeup).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 0090def6 (ACPI: Add interface to register/unregister device
to/from power resources) made it possible to indicate to the ACPI
core that if the given device depends on any power resources, then
it should be resumed as soon as all of the power resources required
by it to transition to the D0 power state have been turned on.
Unfortunately, however, this was a mistake, because all devices
depending on power resources should be treated this way (i.e. they
should be resumed when all power resources required by their D0
state have been turned on) and for the majority of those devices
the ACPI core can figure out by itself which (physical) devices
depend on what power resources.
For this reason, replace the code added by commit 0090def6 with a
new, much more straightforward, mechanism that will be used
internally by the ACPI core and remove all references to that code
from kernel subsystems using ACPI.
For the cases when there are (physical) devices that should be
resumed whenever a not directly related ACPI device node goes into
D0 as a result of power resources configuration changes, like in
the SATA case, add two new routines, acpi_dev_pm_add_dependent()
and acpi_dev_pm_remove_dependent(), allowing subsystems to manage
such dependencies. Convert the SATA subsystem to use the new
functions accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Should use acpi_device pointer directly instead of use handle and
get the device pointer again later.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
All callers of acpi_bus_trim() pass 1 (true) as the second argument
of it, so remove that argument entirely and change acpi_bus_trim()
to always behave as though it were 1.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
With commit f2a33cde55a03 "ACPI: Drop ACPI device .bind() and .unbind()
callbacks", acpi_op_bind and acpi_op_unbind are not used any more. So
remove them.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rafael J. Wysocki
Linus Torvalds
Bjorn Helgaas
Yinghai Lu
Jiang Liu