A PCI Express device can potentially report a link width and speed which it will
not properly fulfill due to being plugged into a slower link higher in the
chain. This function walks up the PCI bus chain and calculates the minimum link
width and speed of this entire chain. This can be useful to enable a device to
determine if it has enough bandwidth for optimum functionality.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
pcie_link_speed and pcix_bus_speed are arrays used by probe.c to correctly
convert lnksta register values into the pci_bus_speed enum. These static arrays
are useful outside probe for this purpose. This patch makes these defines into
conist arrays and exposes them with an extern header in drivers/pci/pci.h
-v2-
* move extern declarations to drivers/pci/pci.h
CC: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Currently, we only update NumVFs register during sriov_enable().
This register should also be updated during sriov_disable() and when
sriov_enable() fails. Otherwise, we will get the stale "Number of VFs"
info from lspci.
[bhelgaas: changelog]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Ben Herrenschmidt reported the following problem:
- The bus has space for all desired MMIO resources, including optional
space for SR-IOV devices
- We attempt to allocate I/O port space, but it fails because the bus
has no I/O space
- Because of the I/O allocation failure, we retry MMIO allocation,
requesting only the required space, without the optional SR-IOV space
This means we don't allocate the optional SR-IOV space, even though we
could.
This is related to 0c5be0cb0e ("PCI: Retry on IORESOURCE_IO type
allocations").
This patch changes how we handle allocation failures. We will now retry
allocation of only the resource type that failed. If MMIO allocation
fails, we'll retry only MMIO allocation. If I/O port allocation fails,
we'll retry only I/O port allocation.
[bhelgaas: changelog]
Reference: https://lkml.kernel.org/r/1367712653.11982.19.camel@pasglop
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org # v3.10+
Convert CONFIG_HOTPLUG_PCI from tristate to bool. This only affects
the hotplug core; several of the hotplug drivers can still be modules.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Hot-removing a device with SR-IOV enabled causes a null pointer dereference
in v3.9 and v3.10.
This is a regression caused by ba518e3c17 ("PCI: pciehp: Iterate over all
devices in slot, not functions 0-7"). When we iterate over the
bus->devices list, we first remove the PF, which also removes all the VFs
from the list. Then the list iterator blows up because more than just the
current entry was removed from the list.
ac205b7bb7 ("PCI: make sriov work with hotplug remove") works around a
similar problem in pci_stop_bus_devices() by iterating over the list in
reverse, so the VFs are stopped and removed from the list first, before the
PF.
This patch changes pciehp_unconfigure_device() to iterate over the list in
reverse, too.
[bhelgaas: bugzilla, changelog]
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=60604
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yijing Wang <wangyijing@huawei.com>
CC: stable@vger.kernel.org # v3.9+
When hot-adding an ACPI host bridge, use
pci_assign_unassigned_root_bus_resources() instead of
pci_assign_unassigned_bus_resources().
The former is more aggressive and will release and reassign existing
resources if necessary. This is safe at hot-add time because no drivers
are bound to devices below the new host bridge yet.
[bhelgaas: changelog, split __init changes out for reviewability]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Resource reallocation is currently done only at boot-time, but will
soon be done when host bridge is hot-added. This patch removes the
__init annotations so the code will still be present after boot.
[bhelgaas: split __init changes out]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
We currently enable PCI bridges after scanning a bus and assigning
resources. This is often done in arch code.
This patch changes this so we don't enable a bridge until necessary, i.e.,
until we enable a PCI device behind the bridge. We do this in the generic
pci_enable_device() path, so this also removes the arch-specific code to
enable bridges.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously, we did resource assignment globally. This patch splits up
pci_assign_unassigned_resources() so assignment is done for each root bus
in turn. We check each root bus individually to see whether it needs any
reassignment, and if it does, we assign resources for just that bus.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
pci_realloc_detect() turns on automatic resource allocation when it finds
unassigned SR-IOV resources. Previously it did this on a global basis, so
we enabled reallocation if any PCI device anywhere had an unassigned SR-IOV
resource.
This patch changes pci_realloc_detect() so it looks at a single bus, so we
can do this when a host bridge is hot-added.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously we did not turn on automatic PCI resource reallocation for
unassigned IOV resources behind a host bridge with address offset. This
patch fixes that bug.
The intent was that "!r->start" would check for a BAR containing zero. But
that check is incorrect for host bridges that apply an offset, because in
that case the resource address is not the same as the bus address.
This patch fixes that by converting the resource address back to a bus
address before checking for zero.
[bhelgaas: changelog]
Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
When CONFIG_PCI_REALLOC_ENABLE_AUTO=y, pci_realloc_detect() looks at PCI
devices to see if any have SR-IOV resources that need to be assigned. If
it finds any, it turns on automatic resource reallocation.
This patch changes pci_realloc_detect() so it uses pci_walk_bus() on
each root bus instead of using for_each_pci_dev(). This is a step
toward doing reallocation on a per-bus basis, so we can do it for
a hot-added host bridge.
[bhelgaas: changelog, rename callback to iov_resources_unassigned(), use
boolean for "unassigned"]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Drop the "bus" temporary variable. No functional change, but simplifies
later patch slightly.
[bhelgaas: changelog, make same change in
pci_assign_unassigned_bridge_resources() to keep it parallel with
pci_assign_unassigned_resources()]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
AMD confirmed that peer-to-peer between these devices is
not possible. We can therefore claim that they support a
subset of ACS.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Donald Dutile <ddutile@redhat.com>
We currently misinterpret that in order for an ACS feature to be
enabled it must be set in the control field. In reality, this means
that the feature is not only enabled, but controllable. Many of the
ACS capability bits are not required if the device behaves by default
in the way specified when both the capability and control bit are set
and does not support or allow the alternate mode. We therefore need
to check the capabilities and mask out flags that are enabled but not
controllable. Egress control seems to be the only flag which is
purely optional.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Donald Dutile <ddutile@redhat.com>
The multifunction ACS rules do not apply to downstream ports. Those
should be tested regardless of whether they are single function or
multifunction. The PCIe spec also fully specifies which PCIe types
are subject to the multifunction rules and excludes event collectors
and PCIe-to-PCI bridges entirely. Document each rule to the section
of the PCIe spec and provide overall documentation of the function.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Donald Dutile <ddutile@redhat.com>
The dev_attrs field of struct class is going away soon, dev_groups
should be used instead. This converts the PCI class code to use the
correct field.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The previous option title "PCI Express support" is confusing. The name
seems to imply this option is required to get PCIe support, which is not
true.
Fix it to "PCI Express Port Bus support" which is more accurate.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Now that acpiphp_check_bridge() always enumerates devices behind the
bridge, there is no need to do that for each sub-bridge anymore like
it is done in the current ACPI-based PCI hotplug (ACPIPHP) code.
Given this we don't need check_sub_bridges() anymore, so drop that
function completely.
This also simplifies the ACPIPHP code a bit.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Do not acquire bridge_mutex around the addition of a slot to its
bridge's list of slots and arount the addition of a function to
its slot's list of functions, because that doesn't help anything
right now (those lists are walked without any locking anyway).
However, acquire bridge_mutex around the list walk in
acpiphp_remove_slots() and use list_for_each_entry() there,
because we terminate the walk as soon as we find the first matching
entry. This prevents that list walk from colliding with bridge
addition and removal.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Notice that functions enable_device() and disable_device() cannot
fail and their return values are ignored in the majority of places,
so redefine them as void and use the opportunity to change their
names to enable_slot() and disable_slot(), respectively, which much
better reflects what they do.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
There is no need for a temporary variable and all the tricks with
ternary operators in acpiphp_get_(latch)|(adapter)_status(). Change
those functions to be a bit more straightforward.
[rjw: Changelog]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The current implementation of acpiphp_check_bridge() is pretty dumb:
- It enables a slot if it's not enabled and the slot status is
ACPI_STA_ALL.
- It disables a slot if it's enabled and the slot status is not
ACPI_STA_ALL.
This behavior is not sufficient to handle the Thunderbolt daisy
chaining case properly, however, because in that case the bus
behind the already enabled slot needs to be rescanned for new
devices.
For this reason, modify acpiphp_check_bridge() so that slots are
disabled and stopped if they are not in the ACPI_STA_ALL state.
For slots in the ACPI_STA_ALL state, devices behind them that don't
respond are trimmed using a new function, trim_stale_devices(),
introduced specifically for this purpose. That function walks
the given bus and checks each device on it. If the device doesn't
respond, it is assumed to be gone and is removed.
Once all of the stale devices directy behind the slot have been
removed, acpiphp_check_bridge() will start looking for new devices
that might have appeared on the given bus. It will do that even if
the slot is already enabled (SLOT_ENABLED is set for it).
In addition to that, make the bus check notification ignore
SLOT_ENABLED and go for enable_device() directly if bridge is NULL,
so that devices behind the slot are re-enumerated in that case too.
This change is based on earlier patches from Kirill A Shutemov
and Mika Westerberg.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Currently, enable_device() checks the return value of pci_scan_slot()
and returns immediately if that's 0 (meaning that no new functions
have been found in the slot). However, if one of the functions in
the slot is a bridge, some new devices may appear below it even if
the bridge itself is present continuously, so it generally is
necessary to do the rescan anyway just in case. [In particular,
that's necessary with the Thunderbolt daisy chaining in which case
new devices may be connected to the existing ones down the chain.]
The correctness of this change relies on the ability of
pcibios_resource_survey_bus() to detect if it has already been called
for the given bus and to skip it if so. Failure to do that will lead
to resource allocation conflicts.
[rjw: Changelog]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
With Thunderbolt you can daisy chain devices: connect new devices to
an already plugged one. In that case the "hotplug slot" is already
enabled, but we still want to look for new PCI devices behind it.
Reuse enable_device() to scan for new PCI devices on enabled slots
and push the SLOT_ENABLED check up into acpiphp_enable_slot().
[rjw: Rebased, modified the changelog]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ACPI-based PCI hotplug (acpiphp) core code need not and really
should not execute _PS0 and _PS3 directly for devices it handles.
First of all, it is not necessary to put devices into D3 after
acpi_bus_trim() has walked through them, because
acpi_device_unregister() invoked by it puts each device into D3cold
before returning. Thus after disable_device() the slot should be
powered down already.
Second, calling _PS0 directly on ACPI device objects may not be
appropriate, because it may require power resources to be set up in
a specific way in advance and that must be taken care of by the ACPI
core. Thus modify acpiphp_bus_add() to power up the device using
the appropriate interface after it has run acpi_bus_scan() on its
handle.
After that, the functions executing _PS0 and _PS3, power_on_slot()
and power_off_slot(), are not necessary any more, so drop them
and update the code calling them accordingly. Also drop the
function flags related to device power states, since they aren't
useful any more too.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Modify handle_hotplug_event() to avoid queing up the execution of
handle_hotplug_event_work_fn() as a work item on kacpi_hotplug_wq
for non-hotplug events, such as ACPI_NOTIFY_DEVICE_WAKE. Move
the code printing diagnostic messages for those events into
handle_hotplug_event().
In addition to that, remove the bogus comment about how the core
should distinguish between hotplug and non-hotplug events and
queue them up on different workqueues. The core clearly cannot
know in advance what events will be interesting to the given
caller of acpi_install_notify_handler().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Both acpiphp_disable_slot() and acpiphp_eject_slot() are always
called together so instead of calling each separately we can
consolidate them into one function acpiphp_disable_and_eject_slot()
that does both (but it will return success on _EJ0 failures that
were ignored in the majority of call sites anyway).
[rjw: Rebased plus minor tweaks]
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Two checks in check_hotplug_bridge() are redundant (they have been
done by the caller already), so drop them.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The acpiphp_bus_trim() and acpiphp_bus_add() functions need not
return error codes that are never checked, so redefine them and
simplify them a bit.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
To avoid chasing more pointers than necessary in some situations,
move the bridge pointer from struct acpiphp_slot to struct
acpiphp_func (and call it 'parent') and add a bus pointer to
struct acpiphp_slot.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The handle field in struct acpiphp_bridge is only used by
acpiphp_enumerate_slots(), but in that function the local handle
variable can be used instead, so make that happen and drop handle
from struct acpiphp_bridge.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The ACPI handle stored in struct acpiphp_func is also stored in the
struct acpiphp_context object containing it and it is trivial to get
from a struct acpiphp_func pointer to the handle field of the outer
struct acpiphp_context.
Hence, the handle field of struct acpiphp_func is redundant, so drop
it and provide a helper function, func_to_handle(), allowing it
users to get the ACPI handle for the given struct acpiphp_func
pointer.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Since there has to be a struct acpiphp_func object for every struct
acpiphp_context created by register_slot(), the struct acpiphp_func
one can be embedded into the struct acpiphp_context one, which allows
some code simplifications to be made.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The only bridge flag used by the ACPI-based PCI hotplug (ACPIPHP)
code is BRIDGE_HAS_EJ0, but it is only used by the event handling
function hotplug_event() and if that flag is set, the corresponding
function flag FUNC_HAS_EJ0 is set as well, so that bridge flag is
redundant.
For this reason, drop BRIDGE_HAS_EJ0 and all code referring to it
and since it is the only bridge flag defined, drop the flags field
from struct acpiphp_bridge entirely.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
If the slot unique number is passed as an additional argument to
acpiphp_register_hotplug_slot(), the 'sun' field in struct
acpiphp_slot is only used by ibm_[s|g]et_attention_status(),
but then it's more efficient to store it in struct slot.
Thus move the 'sun' field from struct acpiphp_slot to struct slot
changing its data type to unsigned int in the process, and redefine
acpiphp_register_hotplug_slot() to take the slot number as separate
argument.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Rework register_slot() to create a struct acpiphp_func object for
every function it is called for and to create acpiphp slots for all
of them. Although acpiphp_register_hotplug_slot() is only called for
the slots whose functions are identified as "ejectable", so that user
space can manipulate them, the ACPIPHP notify handler,
handle_hotplug_event(), is now installed for all of the registered
functions (that aren't dock stations) and hotplug events may be
handled for all of them.
As a result, essentially, all PCI bridges represented by objects in
the ACPI namespace are now going to be "hotplug" bridges and that may
affect resources allocation in general, although it shouldn't lead to
problems.
This allows the code to be simplified substantially and addresses
the problem where bus check or device check notifications for some
PCI bridges or devices are not handled, because those devices are
not recognized as "ejectable" or there appear to be no "ejectable"
devices under those bridges.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
To make the code in register_slot() a bit easier to follow, change
the way the slot allocation part is organized. Drop one local
variable that's not used any more after that modification.
This code change should not lead to any changes in behavior.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Since the func pointer in struct acpiphp_context can always be used
instead of the func pointer in struct acpiphp_bridge, drop the
latter.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
There are separate handling event functions for hotplug bridges and
for hotplug functions, but they may be combined into one common
hotplug event handling function which simplifies the code slightly.
That also allows a theoretical bug to be dealt with which in
principle may occur if a hotplug bridge is on a dock station, because
in that case the bridge-specific notification should be used instead
of the function-specific one, but the dock station always uses the
latter.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Modify handle_hotplug_event() to pass the entire context object
(instead of its fields individually) to work functions started by it.
This change makes the subsequent consolidation of the event handling
work functions a bit more straightforward.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Using the hotplug context objects introduced previously rework the
ACPI-based PCI hotplug (ACPIPHP) core code to get to acpiphp_bridge
objects associated with hotplug bridges from those context objects
rather than from the global list of hotplug bridges.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Using the hotplug context objects introduced previously rework the
ACPI-based PCI hotplug (ACPIPHP) core code so that all notifications
for ACPI device objects corresponding to the hotplug PCI devices are
handled by one function, handle_hotplug_event(), which recognizes
whether it has to handle a bridge or a function.
In addition to code size reduction it allows some ugly pieces of code
where notify handlers have to be uninstalled and installed again to
go away. Moreover, it fixes a theoretically possible race between
handle_hotplug_event() and free_bridge() tearing down data structures
for the same handle.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
When either a new hotplug bridge or a new hotplug function is added
by the ACPI-based PCI hotplug (ACPIPHP) code, attach a context object
to its ACPI handle to store hotplug-related information in it. To
start with, put the handle's bridge and function pointers into that
object. Count references to the context objects and drop them when
they are not needed any more.
First of all, this makes it possible to find out if the given bridge
has been registered as a function already in a much more
straightforward way and acpiphp_bridge_handle_to_function() can be
dropped (Yay!).
This also will allow some more simplifications to be made going
forward.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
When a new ACPIPHP function is added by register_slot() and the
notify handler cannot be installed for it, register_slot() returns an
error status without cleaning up, which causes the entire namespace
walk in acpiphp_enumerate_slots() to be aborted, although it still
may be possible to successfully install the function notify handler
for other device objects under the given brigde.
To address this issue make register_slot() return success after
a new function has been added, even if the addition of the notify
handler for it has failed.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>