Commit Graph
102 Commits
Author SHA1 Message Date
Andy Shevchenko 719cf71cad ACPI / glue: Split dev_is_platform() out of module for wide use
There would be useful to have in future the similar API in platform
core, as we have, for example, for PCI subsystem, to check if device
belongs to it.

Thus, split out conditional to a macro dev_is_platform() for wide use.

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-09-10 12:48:50 +02:00
Linus Torvalds 28b47809b2 Merge tag 'iommu-updates-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel:

 - code optimizations for the Intel VT-d driver

 - ability to switch off a previously enabled Intel IOMMU

 - support for 'struct iommu_device' for OMAP, Rockchip and Mediatek
   IOMMUs

 - header optimizations for IOMMU core code headers and a few fixes that
   became necessary in other parts of the kernel because of that

 - ACPI/IORT updates and fixes

 - Exynos IOMMU optimizations

 - updates for the IOMMU dma-api code to bring it closer to use per-cpu
   iova caches

 - new command-line option to set default domain type allocated by the
   iommu core code

 - another command line option to allow the Intel IOMMU switched off in
   a tboot environment

 - ARM/SMMU: TLB sync optimisations for SMMUv2, Support for using an
   IDENTITY domain in conjunction with DMA ops, Support for SMR masking,
   Support for 16-bit ASIDs (was previously broken)

 - various other small fixes and improvements

* tag 'iommu-updates-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (63 commits)
  soc/qbman: Move dma-mapping.h include to qman_priv.h
  soc/qbman: Fix implicit header dependency now causing build fails
  iommu: Remove trace-events include from iommu.h
  iommu: Remove pci.h include from trace/events/iommu.h
  arm: dma-mapping: Don't override dma_ops in arch_setup_dma_ops()
  ACPI/IORT: Fix CONFIG_IOMMU_API dependency
  iommu/vt-d: Don't print the failure message when booting non-kdump kernel
  iommu: Move report_iommu_fault() to iommu.c
  iommu: Include device.h in iommu.h
  x86, iommu/vt-d: Add an option to disable Intel IOMMU force on
  iommu/arm-smmu: Return IOVA in iova_to_phys when SMMU is bypassed
  iommu/arm-smmu: Correct sid to mask
  iommu/amd: Fix incorrect error handling in amd_iommu_bind_pasid()
  iommu: Make iommu_bus_notifier return NOTIFY_DONE rather than error code
  omap3isp: Remove iommu_group related code
  iommu/omap: Add iommu-group support
  iommu/omap: Make use of 'struct iommu_device'
  iommu/omap: Store iommu_dev pointer in arch_data
  iommu/omap: Move data structures to omap-iommu.h
  iommu/omap: Drop legacy-style device support
  ...
2017-05-09 15:15:47 -07:00
Linus Torvalds ab182e67ec Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:

 - kdump support, including two necessary memblock additions:
   memblock_clear_nomap() and memblock_cap_memory_range()

 - ARMv8.3 HWCAP bits for JavaScript conversion instructions, complex
   numbers and weaker release consistency

 - arm64 ACPI platform MSI support

 - arm perf updates: ACPI PMU support, L3 cache PMU in some Qualcomm
   SoCs, Cortex-A53 L2 cache events and DTLB refills, MAINTAINERS update
   for DT perf bindings

 - architected timer errata framework (the arch/arm64 changes only)

 - support for DMA_ATTR_FORCE_CONTIGUOUS in the arm64 iommu DMA API

 - arm64 KVM refactoring to use common system register definitions

 - remove support for ASID-tagged VIVT I-cache (no ARMv8 implementation
   using it and deprecated in the architecture) together with some
   I-cache handling clean-up

 - PE/COFF EFI header clean-up/hardening

 - define BUG() instruction without CONFIG_BUG

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits)
  arm64: Fix the DMA mmap and get_sgtable API with DMA_ATTR_FORCE_CONTIGUOUS
  arm64: Print DT machine model in setup_machine_fdt()
  arm64: pmu: Wire-up Cortex A53 L2 cache events and DTLB refills
  arm64: module: split core and init PLT sections
  arm64: pmuv3: handle pmuv3+
  arm64: Add CNTFRQ_EL0 trap handler
  arm64: Silence spurious kbuild warning on menuconfig
  arm64: pmuv3: use arm_pmu ACPI framework
  arm64: pmuv3: handle !PMUv3 when probing
  drivers/perf: arm_pmu: add ACPI framework
  arm64: add function to get a cpu's MADT GICC table
  drivers/perf: arm_pmu: split out platform device probe logic
  drivers/perf: arm_pmu: move irq request/free into probe
  drivers/perf: arm_pmu: split cpu-local irq request/free
  drivers/perf: arm_pmu: rename irq request/free functions
  drivers/perf: arm_pmu: handle no platform_device
  drivers/perf: arm_pmu: simplify cpu_pmu_request_irqs()
  drivers/perf: arm_pmu: factor out pmu registration
  drivers/perf: arm_pmu: fold init into alloc
  drivers/perf: arm_pmu: define armpmu_init_fn
  ...
2017-05-05 12:11:37 -07:00
Joerg Roedel 2c0248d688 Merge branches 'arm/exynos', 'arm/omap', 'arm/rockchip', 'arm/mediatek', 'arm/smmu', 'arm/core', 'x86/vt-d', 'x86/amd' and 'core' into next 2017-05-04 18:06:17 +02:00
Sricharan R 09515ef5dd of/acpi: Configure dma operations at probe time for platform/amba/pci bus devices
Configuring DMA ops at probe time will allow deferring device probe when
the IOMMU isn't available yet. The dma_configure for the device is
now called from the generic device_attach callback just before the
bus/driver probe is called. This way, configuring the DMA ops for the
device would be called at the same place for all bus_types, hence the
deferred probing mechanism should work for all buses as well.

pci_bus_add_devices    (platform/amba)(_device_create/driver_register)
       |                         |
pci_bus_add_device     (device_add/driver_register)
       |                         |
device_attach           device_initial_probe
       |                         |
__device_attach_driver    __device_attach_driver
       |
driver_probe_device
       |
really_probe
       |
dma_configure

Similarly on the device/driver_unregister path __device_release_driver is
called which inturn calls dma_deconfigure.

This patch changes the dma ops configuration to probe time for
both OF and ACPI based platform/amba/pci bus devices.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci part)
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sricharan R <sricharan@codeaurora.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-04-20 16:31:06 +02:00
Rafael J. Wysocki fdad4e7a87 ACPI / scan: Prefer devices without _HID for _ADR matching
Commit c2a6bbaf0c (ACPI / scan: Prefer devices without _HID/_CID
for _ADR matching) added a list_empty(&adev->pnp.ids) check to
find_child_checks() so as to catch situations in which the ACPI
core attempts to decode _ADR for a device having a _HID too which
is strictly against the spec.  However, it overlooked the fact that
the adev->pnp.ids list for the devices taken into account by
find_child_checks() may contain device IDs set internally by the
kernel, like "LNXVIDEO" (thanks to Zhang Rui for that realization),
and it broke the enumeration of those devices as a result.

To unbreak it, replace the overly coarse grained list_empty()
check with a much more precise check against the pnp.type.platform_id
flag which is only set for devices having a _HID (that's how it
should be done from the start, as having both _ADR and _CID is
actually permitted).

Fixes: c2a6bbaf0c (ACPI / scan: Prefer devices without _HID/_CID for _ADR matching)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=194889
Reported-and-tested-by: Mike <mike@mikewilson.me.uk>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Cc: 4.10+ <stable@vger.kernel.org> # 4.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-04-01 00:55:22 +02:00
Hanjun Guo d4f54a1866 ACPI: platform: setup MSI domain for ACPI based platform device
By allowing platform MSI domain to be created on ACPI platforms,
a platform device MSI domain can be set-up when it is probed.

In order to do that, the MSI domain the platform device connects
to should be retrieved, so the iort_get_platform_device_domain() is
introduced to retrieve the domain from the IORT kernel layer.

With the domain retrieved, we need a proper way to set the
domain to platform device.

Given that some platform devices (irqchips) require the MSI irqdomain
to be their interrupt parent domain, the MSI irqdomain should be
determined before platform device is probed but after the platform
device is allocated which means that the code setting up the MSI
irqdomain, ie acpi_configure_pmsi_domain() should be called in
acpi_platform_notify() (that is triggered after adding a device but
before the respective driver is probed) for the platform MSI domain
code set-up path to work properly.

Acked-by: Rafael J. Wysocki <rafael@kernel.org> [for glue.c]
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
[lorenzo.pieralisi@arm.com: rewrote commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Ming Lei <ming.lei@canonical.com>
Tested-by: Wei Xu <xuwei5@hisilicon.com>
Tested-by: Sinan Kaya <okaya@codeaurora.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Tomasz Nowicki <tn@semihalf.com>
2017-03-30 10:20:01 +01:00
Rafael J. Wysocki c2a6bbaf0c ACPI / scan: Prefer devices without _HID/_CID for _ADR matching
The way acpi_find_child_device() works currently is that, if there
are two (or more) devices with the same _ADR value in the same
namespace scope (which is not specifically allowed by the spec and
the OS behavior in that case is not defined), the first one of them
found to be present (with the help of _STA) will be returned.

This covers the majority of cases, but is not sufficient if some of
the devices in question have a _HID (or _CID) returning some valid
ACPI/PNP device IDs (which is disallowed by the spec) and the
ASL writers' expectation appears to be that the OS will match
devices without a valid ACPI/PNP device ID against a given bus
address first.

To cover this special case as well, modify find_child_checks()
to prefer devices without ACPI/PNP device IDs over devices that
have them.

Suggested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
2017-01-02 22:21:59 +01:00
Lorenzo Pieralisi 709f94ff01 ACPI: Drop misplaced acpi_dma_deconfigure() call from acpi_bind_one()
The acpi_bind_one() error return path can be hit either on physical node
allocation failure or if the device being configured is already
associated with an ACPI node and its ACPI companion does not match the
one acpi_bind_one() is setting it up with. In both cases the error
return path is executed before DMA is configured for a device therefore
there is no need to call acpi_dma_deconfigure() on the function error
return path.

Furthermore, if acpi_bind_one() does configure DMA for a device (ie it
successfully executes acpi_dma_configure()) acpi_bind_one() always
completes execution successfully hence there is no need to add an exit
path to deconfigure the DMA set-up (ie by calling acpi_dma_deconfigure()).

Remove the misplaced acpi_dma_deconfigure() in acpi_bind_one() to
reinstate its correct error return path behaviour.

Fixes: d760a1baf2 (ACPI: Implement acpi_dma_configure)
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-26 23:15:36 +01:00
Lorenzo Pieralisi d760a1baf2 ACPI: Implement acpi_dma_configure
On DT based systems, the of_dma_configure() API implements DMA
configuration for a given device. On ACPI systems an API equivalent to
of_dma_configure() is missing which implies that it is currently not
possible to set-up DMA operations for devices through the ACPI generic
kernel layer.

This patch fills the gap by introducing acpi_dma_configure/deconfigure()
calls that for now are just wrappers around arch_setup_dma_ops() and
arch_teardown_dma_ops() and also updates ACPI and PCI core code to use
the newly introduced acpi_dma_configure/acpi_dma_deconfigure functions.

Since acpi_dma_configure() is used to configure DMA operations, the
function initializes the dma/coherent_dma masks to sane default values
if the current masks are uninitialized (also to keep the default values
consistent with DT systems) to make sure the device has a complete
default DMA set-up.

The DMA range size passed to arch_setup_dma_ops() is sized according
to the device coherent_dma_mask (starting at address 0x0), mirroring the
DT probing path behaviour when a dma-ranges property is not provided
for the device being probed; this changes the current arch_setup_dma_ops()
call parameters in the ACPI probing case, but since arch_setup_dma_ops()
is a NOP on all architectures but ARM/ARM64 this patch does not change
the current kernel behaviour on them.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> [pci]
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Tomasz Nowicki <tn@semihalf.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Tomasz Nowicki <tn@semihalf.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Tomasz Nowicki <tn@semihalf.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-11-29 15:57:44 +00:00
Rafael J. Wysocki f2115faaf0 Merge branch 'acpi-pci'
* acpi-pci:
  PCI: ACPI: Add support for PCI device DMA coherency
  PCI: OF: Move of_pci_dma_configure() to pci_dma_configure()
  of/pci: Fix pci_get_host_bridge_device leak
  device property: ACPI: Remove unused DMA APIs
  device property: ACPI: Make use of the new DMA Attribute APIs
  device property: Adding DMA Attribute APIs for Generic Devices
  ACPI: Adding DMA Attribute APIs for ACPI Device
  device property: Introducing enum dev_dma_attr
  ACPI: Honor ACPI _CCA attribute setting

Conflicts:
	drivers/crypto/ccp/ccp-platform.c
2015-11-07 01:30:10 +01:00
Suthikulpanit, Suravee 1831eff876 device property: ACPI: Make use of the new DMA Attribute APIs
Now that we have the new DMA attribute APIs, we can replace the older
acpi_check_dma() and device_dma_is_coherent().

Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-07 01:29:22 +01:00
Rami Rosen c33cab60bc ACPI: change init_acpi_device_notify() to return void
This patch changes the type of the return value of the init_acpi_device_notify()
method to be void, as this method never fails and its return value is never
used.

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-15 03:01:01 +02:00
Suthikulpanit, Suravee d056267483 ACPI / scan: Parse _CCA and setup device coherency
This patch implements support for ACPI _CCA object, which is introduced in
ACPIv5.1, can be used for specifying device DMA coherency attribute.

The parsing logic traverses device namespace to parse coherency
information, and stores it in acpi_device_flags. Then uses it to call
arch_setup_dma_ops() when creating each device enumerated in DSDT
during ACPI scan.

This patch also introduces acpi_dma_is_coherent(), which provides
an interface for device drivers to check the coherency information
similarly to the of_dma_is_coherent().

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-15 14:40:48 +02:00
Rafael J. Wysocki ca5b74d267 ACPI: Introduce has_acpi_companion()
Now that the ACPI companions of devices are represented by pointers
to struct fwnode_handle, it is not quite efficient to check whether
or not an ACPI companion of a device is present by evaluating the
ACPI_COMPANION() macro.

For this reason, introduce a special static inline routine for that,
has_acpi_companion(), and update the code to use it where applicable.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-16 23:49:08 +01:00
Rafael J. Wysocki 9cb32acf09 ACPI / scan: Add bind/unbind callbacks to struct acpi_scan_handler
In some cases it may be necessary to perform certain setup/cleanup
operations on a device object representing a physical device after
it has been associated with an ACPI companion by acpi_bind_one() or
before disassociating it from that companion by acpi_unbind_one(),
respectively.  If there is a struct acpi_bus_type object for the
given device's bus type, the .setup()/.cleanup() callbacks from there
are executed for these purposes.  However, an analogous mechanism will
be necessary for devices whose bus types don't have corresponding
struct acpi_bus_type objects and that have specific ACPI scan handlers.

For those devices, add new .bind() and .unbind() callbacks to struct
acpi_scan_handler that will be executed by acpi_platform_notify()
right after the given device has been associated with an ACPI
comapnion and by acpi_platform_notify_remove() right before calling
acpi_unbind_one() for that device, respectively.

To make that work for scan handlers registering new devices in their
.attach() callbacks, modify acpi_scan_attach_handler() to set the
ACPI device object's handler field before calling .attach() from the
scan handler at hand.

This changeset includes a fix from Mika Westerberg.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-11 00:35:46 +01:00
Rafael J. Wysocki bfecc2b3e3 ACPI / bind: Move acpi_get_child() to drivers/ide/ide-acpi.c
Since drivers/ide/ide-acpi.c is the only remaining user of
acpi_get_child(), move that function into that file as a static
routine.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-12-07 01:05:50 +01:00
Rafael J. Wysocki 24dee1fc99 ACPI / bind: Pass struct acpi_device pointer to acpi_bind_one()
There is no reason to pass an ACPI handle to acpi_bind_one() instead
of a struct acpi_device pointer to the target device object, so
modify that function to take a struct acpi_device pointer as its
second argument and update all code depending on it accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Lan Tianyu <tianyu.lan@intel.com> # for USB/ACPI
2013-12-07 01:05:50 +01:00
Rafael J. Wysocki e3f02c5228 ACPI / bind: Rework struct acpi_bus_type
Replace the .find_device function pointer in struct acpi_bus_type
with a new one, .find_companion, that is supposed to point to a
function returning struct acpi_device pointer (instead of an int)
and takes one argument (instead of two).  This way the role of
this callback is more clear and the implementation of it can
be more straightforward.

Update all of the users of struct acpi_bus_type (PCI, PNP/ACPI and
USB) to reflect the structure change.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Lan Tianyu <tianyu.lan@intel.com> # for USB/ACPI
2013-12-07 01:05:50 +01:00
Rafael J. Wysocki 9c5ad36d98 ACPI / bind: Redefine acpi_preset_companion()
Modify acpi_preset_companion() to take a struct acpi_device pointer
instead of an ACPI handle as its second argument and redefine it as
a static inline wrapper around ACPI_COMPANION_SET() passing the
return value of acpi_find_child_device() directly as the second
argument to it.  Update its users to pass struct acpi_device
pointers instead of ACPI handles to it.

This allows some unnecessary acpi_bus_get_device() calls to be
avoided.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Aaron Lu <aaron.lu@intel.com> # for ATA binding
2013-12-07 01:05:49 +01:00
Rafael J. Wysocki 11dcc75dba ACPI / bind: Redefine acpi_get_child()
Since acpi_get_child() is the only user of acpi_find_child() now,
drop the static inline definition of the former and redefine the
latter as new acpi_get_child().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Aaron Lu <aaron.lu@intel.com> # for ATA binding
2013-12-07 01:05:49 +01:00
Rafael J. Wysocki 5ce79d2013 PCI / ACPI: Use acpi_find_child_device() for child devices lookup
It is much more efficient to use acpi_find_child_device()
for child devices lookup in acpi_pci_find_device() and pass
ACPI_COMPANION(dev->parent) to it directly instead of obtaining
ACPI_HANDLE() of ACPI_COMPANION(dev->parent) and passing it to
acpi_find_child() which has to run acpi_bus_get_device() to
obtain ACPI_COMPANION(dev->parent) from that again.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
2013-12-07 01:05:48 +01:00
Rafael J. Wysocki d9fef0c4d2 ACPI / bind: Simplify child device lookups
Now that we create a struct acpi_device object for every ACPI
namespace node representing a device, it is not necessary to
use acpi_walk_namespace() for child device lookup in
acpi_find_child() any more.  Instead, we can simply walk the
list of children of the given struct acpi_device object and
return the matching one (or the one which is the best match if
there are more of them).  The checks done during the matching
loop can be simplified too so that the secondary namespace walks
in find_child_checks() are not necessary any more.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
2013-12-07 01:05:48 +01:00
Rafael J. Wysocki a104b4d467 ACPI / bind: Use (put|get)_device() on ACPI device objects too
When associating a "physical" device with an ACPI device object
acpi_bind_one() only uses get_device() to increment the reference
counter of the former, but there is no reason not to do that with
the latter too.  Among other things, that may help to avoid
use-after-free when an ACPI device object is freed without calling
acpi_unbind_one() for all "physical" devices associated with it
(that only can happen in buggy code, but then it's better if the
kernel doesn't crash as a result of a bug).

For this reason, modify acpi_bind_one() to apply get_device() to
the ACPI device object too and update acpi_unbind_one() to drop
that reference using put_device() as appropriate.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Lan Tianyu <tianyu.lan@intel.com>
2013-11-14 23:18:32 +01:00
Rafael J. Wysocki 7b1998116b ACPI / driver core: Store an ACPI device pointer in struct acpi_dev_node
Modify struct acpi_dev_node to contain a pointer to struct acpi_device
associated with the given device object (that is, its ACPI companion
device) instead of an ACPI handle corresponding to it.  Introduce two
new macros for manipulating that pointer in a CONFIG_ACPI-safe way,
ACPI_COMPANION() and ACPI_COMPANION_SET(), and rework the
ACPI_HANDLE() macro to take the above changes into account.
Drop the ACPI_HANDLE_SET() macro entirely and rework its users to
use ACPI_COMPANION_SET() instead.  For some of them who used to
pass the result of acpi_get_child() directly to ACPI_HANDLE_SET()
introduce a helper routine acpi_preset_companion() doing an
equivalent thing.

The main motivation for doing this is that there are things
represented by struct acpi_device objects that don't have valid
ACPI handles (so called fixed ACPI hardware features, such as
power and sleep buttons) and we would like to create platform
device objects for them and "glue" them to their ACPI companions
in the usual way (which currently is impossible due to the
lack of valid ACPI handles).  However, there are more reasons
why it may be useful.

First, struct acpi_device pointers allow of much better type checking
than void pointers which are ACPI handles, so it should be more
difficult to write buggy code using modified struct acpi_dev_node
and the new macros.  Second, the change should help to reduce (over
time) the number of places in which the result of ACPI_HANDLE() is
passed to acpi_bus_get_device() in order to obtain a pointer to the
struct acpi_device associated with the given "physical" device,
because now that pointer is returned by ACPI_COMPANION() directly.
Finally, the change should make it easier to write generic code that
will build both for CONFIG_ACPI set and unset without adding explicit
compiler directives to it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> # on Haswell
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com> # for ATA and SDIO part
2013-11-14 23:14:43 +01:00