Make device_get_next_child_node() work with ACPI data-only subnodes
introduced previously.

Namely, replace acpi_get_next_child() with acpi_get_next_subnode()
that can handle (and return) child device objects as well as child
data-only subnodes of the given device and modify the ACPI part
of the GPIO subsystem to handle data-only subnodes returned by it.

To that end, introduce acpi_node_get_gpiod() taking a struct
fwnode_handle pointer as the first argument.  That argument may
point to an ACPI device object as well as to a data-only subnode
and the function should do the right thing (ie. look for the matching
GPIO descriptor correctly) in either case.

Next, modify fwnode_get_named_gpiod() to use acpi_node_get_gpiod()
instead of acpi_get_gpiod_by_index() which automatically causes
devm_get_gpiod_from_child() to work with ACPI data-only subnodes
that may be returned by device_get_next_child_node() which in turn
is required by the users of that function (the gpio_keys_polled
and gpio-leds drivers).
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>

Some devices, like MFD subdevices, share a single ACPI companion device so
that they are able to access their resources and children. However,
currently all these subdevices are attached to the ACPI power domain and
this might cause that the power methods for the companion device get called
more than once.

In order to solve this we attach the ACPI power domain only to the first
physical device that is bound to the ACPI companion device. In case of MFD
devices, this is the parent MFD device itself.
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NLee Jones <lee.jones@linaro.org>

Move the registration of the ACPI bus type to acpi_bus_init() and
avoid using ACPI going forward if it fails (too many things depend on
the presence of the ACPI bus type).
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

To reduce the size of scan.c and improve the readability of it, move
code related to device notification, the definitions of the ACPI bus
operations and the driver management code to drivers/acpi/bus.c.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

To reduce the size of scan.c and improve the readability of it, move
code related device matching into drivers/acpi/bus.c.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

To reduce the size of scan.c and improve the readability of it, move
all code related to device sysfs, modalias creation etc. to a new
file called device_sysfs.c.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Device drivers typically use ACPI _HIDs/_CIDs listed in struct device_driver
acpi_match_table to match devices. However, for generic drivers, we do not
want to list _HID for all supported devices. Also, certain classes of devices
do not have _CID (e.g. SATA, USB). Instead, we can leverage ACPI _CLS,
which specifies PCI-defined class code (i.e. base-class, subclass and
programming interface). This patch adds support for matching ACPI devices using
the _CLS method.

To support loadable module, current design uses _HID or _CID to match device's
modalias. With the new way of matching with _CLS this would requires modification
to the current ACPI modalias key to include _CLS. This patch appends PCI-defined
class-code to the existing ACPI modalias as following.

    acpi:<HID>:<CID1>:<CID2>:..:<CIDn>:<bbsspp>:
E.g:
    # cat /sys/devices/platform/AMDI0600:00/modalias
    acpi:AMDI0600:010601:

where bb is th base-class code, ss is te sub-class code, and pp is the
programming interface code

Since there would not be _HID/_CID in the ACPI matching table of the driver,
this patch adds a field to acpi_device_id to specify the matching _CLS.

    static const struct acpi_device_id ahci_acpi_match[] = {
        { ACPI_DEVICE_CLASS(PCI_CLASS_STORAGE_SATA_AHCI, 0xffffff) },
        {},
    };

In this case, the corresponded entry in modules.alias file would be:

    alias acpi*:010601:* ahci_platform
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This allows video_detect.c to be build as a module, this is a preparation
patch for the backlight interface selection logic cleanup.

Note this commit also causes acpi_is_video_device() to always be build
indepedent of CONFIG_ACPI_VIDEO, as there is no reason to make its
building depend on CONFIG_ACPI_VIDEO.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Acked-by: NDarren Hart <dvhart@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NMark Salter <msalter@redhat.com>
Signed-off-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Make the button ACPI device ID array static const. Safes us a little bit
of code.
Signed-off-by: NMathias Krause <minipli@googlemail.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Use a #defined symbol ACPI_DT_NAMESPACE_HID instead of the PRP0001
string.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NHanjun Guo <hanjun.guo@linaro.org>

The ACPI 6 specification has made some changes in the device power
management area.  In particular:

 * The D3hot power state is now supposed to be always available
   (instead of D3cold) and D3cold is only regarded as valid if the
   _PR3 object is present for the given device.

 * The required ordering of transitions into power states deeper than
   D0 is now such that for a transition into state Dx the _PSx method
   is supposed to be executed first, if present, and the states of
   the power resources the device depends on are supposed to be
   changed after that.

 * It is now explicitly forbidden to transition devices from
   lower-power (deeper) into higher-power (shallower) power states
   other than D0.

Those changes have been made so the specification reflects the
Windows' device power management code that the vast majority of
systems using ACPI is validated against.

To avoid artificial differences in ACPI device power management
between Windows and Linux, modify the ACPI device power management
code to follow the new specification.  Add comments explaining the
code flow in some unclear places.

This only may affect some real corner cases in which the OS behavior
expected by the firmware is different from the Windows one, but that's
quite unlikely.  The transition ordering change affects transitions
to D1 and D2 which are rarely used (if at all) and into D3hot and
D3cold for devices actually having _PR3, but those are likely to
be validated against Windows anyway.  The other changes may affect
code calling acpi_device_get_power() or acpi_device_update_power()
where ACPI_STATE_D3_HOT may be returned instead of ACPI_STATE_D3_COLD
(that's why the ACPI fan driver needs to be updated too) and since
transitions into ACPI_STATE_D3_HOT may remove power now, it is better
to avoid this one in acpi_pm_device_sleep_state() if the "no power
off" PM QoS flag is set.

The only existing user of acpi_device_can_poweroff() really cares
about the case when _PR3 is present, so the change in that function
should not cause any problems to happen too.

A plus is that PCI_D3hot can be mapped to ACPI_STATE_D3_HOT
now and the compatibility with older systems should be covered
automatically.

In any case, if any real problems result from this, it still will
be better to follow the Windows' behavior (which now is reflected
by the specification too) in general and handle the cases when it
doesn't work via quirks.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

If the special PRP0001 device ID is present in the given device's list
of ACPI/PNP IDs and the device has a valid "compatible" property in
the _DSD, it should be enumerated using the default mechanism,
unless some scan handlers match the IDs preceding PRP0001 in the
device's list of ACPI/PNP IDs.  In addition to that, no scan handlers
matching the IDs following PRP0001 in that list should be attached
to the device.

To make that happen, define a scan handler that will match PRP0001
and trigger the default enumeration for the matching devices if the
"compatible" property is present for them.

Since that requires the check for platform_id and device->handler
to be removed from acpi_default_enumeration(), move the fallback
invocation of acpi_default_enumeration() to acpi_bus_attach()
(after it's checked if there's a matching ACPI driver for the
device), which is a better place to call it, and do the platform_id
check in there too (device->handler is guaranteed to be unset at
the point where the function is looking for a matching ACPI driver).
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NDarren Hart <dvhart@linux.intel.com>

acpi_scan_is_offline() may be called under the physical_node_lock
lock of the given device object's parent, so prevent lockdep from
complaining about that by annotating that instance with
SINGLE_DEPTH_NESTING.

Fixes: caa73ea1 (ACPI / hotplug / driver core: Handle containers in a special way)
Reported-and-tested-by: NXie XiuQi <xiexiuqi@huawei.com>
Reviewed-by: NToshi Kani <toshi.kani@hp.com>
Cc: 3.14+ <stable@vger.kernel.org> # 3.14+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit e1acdeb0 "ACPI / scan: Simplify acpi_match_device()"
introduced code that may lead to a NULL pointer dereference when
trying to unlock a mutex.  Fix that.

Fixes: e1acdeb0 "ACPI / scan: Simplify acpi_match_device()"
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Currently, the ACPI modalias creation covers two mutually exclusive
cases: If the PRP0001 device ID is present in the device's list of
ACPI/PNP IDs and the "compatible" property is present in _DSD, the
created modalias will follow the OF rules of modalias creation.
Otherwise, ACPI rules are used.

However, that is not really desirable, because the presence of PRP0001
in the list of device IDs generally does not preclude using other
ACPI/PNP IDs with that device and those other IDs may be of higher
priority.  In those cases, the other IDs should take preference over
PRP0001 and therefore they also should be present in the modalias.

For this reason, rework the modalias creation for ACPI so that it
shows both the ACPI-style and OF-style modalias strings if the
device has a non-empty list of ACPI/PNP IDs (other than PRP0001)
and a valid "compatible" property at the same time.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>

If the special PRP0001 device ID is present in a device's _CID list,
it should not prevent any ACPI/PNP IDs preceding it in the device's
list of identifiers from being matched first.  That is, only if none
of the IDs preceding PRP0001 in the device's PNP/ACPI IDs list
matches the IDs recognized by the driver, the driver's list of
"compatible" IDs should be matched against the device's "compatible"
property, if present.

In addition to that, drivers can provide both acpi_match_table and
of_match_table at the same time and the of_compatible matching
should be used in that case too if PRP0001 is present in the
device's list of identifiers.

To make that happen, rework acpi_driver_match_device() to do the
"compatible" property check in addition to matching the driver's
list of ACPI IDs against the device's one.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>

Redefine acpi_companion_match() to return an ACPI device object
pointer instead of a bool and use it to remove some redundant code
from acpi_match_device().
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>

Redefine the function used for matching the device's "compatible"
property against a given list of "compatible" strings to take
a pointer to that list instead of a driver object pointer to
make it more general.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>

The fixed event handler should return a value that is either 0 or 1
meanning if the event is handled or not, instead of an acpi_status to
mean if the handler runs well or not.
Suggested-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NAaron Lu <aaron.lu@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This new feature is to interpret AMD specific ACPI device to
platform device such as I2C, UART, GPIO found on AMD CZ and
later chipsets. It based on example intel LPSS. Now, it can
support AMD I2C, UART and GPIO.
Signed-off-by: NKen Xue <Ken.Xue@amd.com>
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

If an ACPI device object whose _STA returns 0 (not present and not
functional) has _PR0 or _PS0, its power_manageable flag will be set
and acpi_bus_init_power() will return 0 for it.  Consequently, if
such a device object is passed to the ACPI device PM functions, they
will attempt to carry out the requested operation on the device,
although they should not do that for devices that are not present.

To fix that problem make acpi_bus_init_power() return an error code
for devices that are not present which will cause power_manageable to
be cleared for them as appropriate in acpi_bus_get_power_flags().
However, the lists of power resources should not be freed for the
device in that case, so modify acpi_bus_get_power_flags() to keep
those lists even if acpi_bus_init_power() returns an error.
Accordingly, when deciding whether or not the lists of power
resources need to be freed, acpi_free_power_resources_lists()
should check the power.flags.power_resources flag instead of
flags.power_manageable, so make that change too.

Furthermore, if acpi_bus_attach() sees that flags.initialized is
unset for the given device, it should reset the power management
settings of the device and re-initialize them from scratch instead
of relying on the previous settings (the device may have appeared
after being not present previously, for example), so make it use
the 'valid' flag of the D0 power state as the initial value of
flags.power_manageable for it and call acpi_bus_init_power() to
discover its current power state.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Cc: 3.10+ <stable@vger.kernel.org> # 3.10+

Two _DEP-related failure messages are printed as dev_err() which is
unnecessary and annoying.  Use dev_dbg() to print them.

While at it, one of the messages should actually say it is related
to _DEP, so modify it to that effect.

Fixes: 40e7fcb1 (ACPI: Add _DEP support to fix battery issue on Asus T100TA)
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI 5.0 introduces _DEP (Operation Region Dependencies) to designate
device objects that OSPM should assign a higher priority in start
ordering due to future operation region accesses.

On Asus T100TA, ACPI battery info are read from a I2C slave device via
I2C operation region. Before I2C operation region handler is installed,
battery _STA always returns 0. There is a _DEP method of designating
start order under battery device node.

This patch is to implement _DEP feature to fix battery issue on the
Asus T100TA.  Introducing acpi_dep_list and adding dep_unmet count
in struct acpi_device. During ACPI namespace scan, create struct
acpi_dep_data for a valid pair of master (device pointed to by _DEP)/
slave(device with _DEP), record master's and slave's ACPI handle in
it and put it into acpi_dep_list. The dep_unmet count will increase
by one if there is a device under its _DEP. Driver's probe() should
return EPROBE_DEFER when find dep_unmet is larger than 0. When I2C
operation region handler is installed, remove all struct acpi_dep_data
on the acpi_dep_list whose master is pointed to I2C host controller
and decrease slave's dep_unmet. When dep_unmet decreases to 0, all
_DEP conditions are met and then do acpi_bus_attach() for the device
in order to resolve battery _STA issue on the Asus T100TA.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=69011Tested-by: NJan-Michael Brummer <jan.brummer@tabos.org>
Tested-by: NAdam Williamson <adamw@happyassassin.net>
Tested-by: NMichael Shigorin <shigorin@gmail.com>
Acked-by: NWolfram Sang <wsa@the-dreams.de>
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Add new generic routines are provided for retrieving properties from
device description objects in the platform firmware in case there are
no struct device objects for them (either those objects have not been
created yet or they do not exist at all).

The following functions are provided:

fwnode_property_present()
fwnode_property_read_u8()
fwnode_property_read_u16()
fwnode_property_read_u32()
fwnode_property_read_u64()
fwnode_property_read_string()
fwnode_property_read_u8_array()
fwnode_property_read_u16_array()
fwnode_property_read_u32_array()
fwnode_property_read_u64_array()
fwnode_property_read_string_array()

in analogy with the corresponding functions for struct device added
previously.  For all of them, the first argument is a pointer to struct
fwnode_handle (new type) that allows a device description object
(depending on what platform firmware interface is in use) to be
obtained.

Add a new macro device_for_each_child_node() for iterating over the
children of the device description object associated with a given
device and a new function device_get_child_node_count() returning the
number of a given device's child nodes.

The interface covers both ACPI and Device Trees.
Suggested-by: NGrant Likely <grant.likely@linaro.org>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NGrant Likely <grant.likely@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We have lots of existing Device Tree enabled drivers and allocating
separate _HID for each is not feasible. Instead we allocate special _HID
"PRP0001" that means that the match should be done using Device Tree
compatible property using driver's .of_match_table instead if the driver
is missing .acpi_match_table.

If there is a need to distinguish from where the device is enumerated
(DT/ACPI) driver can check dev->of_node or ACPI_COMPATION(dev).
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NGrant Likely <grant.likely@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Device Tree is used in many embedded systems to describe the system
configuration to the OS. It supports attaching properties or name-value
pairs to the devices it describe. With these properties one can pass
additional information to the drivers that would not be available
otherwise.

ACPI is another configuration mechanism (among other things) typically
seen, but not limited to, x86 machines. ACPI allows passing arbitrary
data from methods but there has not been mechanism equivalent to Device
Tree until the introduction of _DSD in the recent publication of the
ACPI 5.1 specification.

In order to facilitate ACPI usage in systems where Device Tree is
typically used, it would be beneficial to standardize a way to retrieve
Device Tree style properties from ACPI devices, which is what we do in
this patch.

If a given device described in ACPI namespace wants to export properties it
must implement _DSD method (Device Specific Data, introduced with ACPI 5.1)
that returns the properties in a package of packages. For example:

	Name (_DSD, Package () {
		ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
		Package () {
			Package () {"name1", <VALUE1>},
			Package () {"name2", <VALUE2>},
			...
		}
	})

The UUID reserved for properties is daffd814-6eba-4d8c-8a91-bc9bbf4aa301
and is documented in the ACPI 5.1 companion document called "_DSD
Implementation Guide" [1], [2].

We add several helper functions that can be used to extract these
properties and convert them to different Linux data types.

The ultimate goal is that we only have one device property API that
retrieves the requested properties from Device Tree or from ACPI
transparent to the caller.

[1] http://www.uefi.org/sites/default/files/resources/_DSD-implementation-guide-toplevel.htm
[2] http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdfReviewed-by: NHanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
Reviewed-by: NGrant Likely <grant.likely@linaro.org>
Signed-off-by: NDarren Hart <dvhart@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 6ab34301 ("mfd: Add ACPI support") made the MFD subdevices
share the parent MFD ACPI companion if no _HID/_CID is specified for
the subdevice in mfd_cell description. However, since all the subdevices
share the ACPI companion, the match and modalias generation logic started
to use the ACPI companion as well resulting this:

  # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias
  acpi:INT33D1:PNP0C50:

instead of the expected one

  # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias
  platform:HID-SENSOR-200041

In other words the subdevice modalias is overwritten by the one taken from
ACPI companion. This causes udev not to load the driver anymore.

It is useful to be able to share the ACPI companion so that MFD subdevices
(and possibly other devices as well) can access the ACPI resources even if
they do not have ACPI representation in the namespace themselves.

An example where this is used is Minnowboard LPC driver that creates GPIO
as a subdevice among other things. Without the ACPI companion gpiolib is
not able to lookup the corresponding GPIO controller from ACPI GpioIo
resource.

To fix this, restrict the match and modalias logic to be limited to the
first (primary) physical device associated with the given ACPI comapnion.
The secondary devices will still be able to access the ACPI companion,
but they will be matched in a different way.

Fixes: 6ab34301 (mfd: Add ACPI support)
Reported-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This patch is partial linuxized result of the following ACPICA commit:
  ACPICA commit: a73b66c6aa1846d055bb6390d9c9b9902f7d804d
  Subject: Add "has handler" flag to event/gpe status interfaces.
  This change adds a new flag, ACPI_EVENT_FLAGS_HAS_HANDLER to the
  acpi_get_event_status and acpi_get_gpe_status external interfaces. It
  is set if the event/gpe currently has a handler associated with it.
This patch contains the code to rename ACPI_EVENT_FLAG_HANDLE to
ACPI_EVENT_FLAG_HAS_HANDLER, and the corresponding updates of its usages.

Link: https://github.com/acpica/acpica/commit/a73b66c6Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There is a typo, it should be negative -errno instead.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 46394fd0 (ACPI / hotplug: Move container-specific code out of
the core) removed the generation of "online" uevents for containers,
because "add" uevents are now generated for them automatically when
container system devices are registered.  However, there are user
space tools that need to be notified when the container and all of
its children have been enumerated, which doesn't happen any more.

For this reason, add a mechanism allowing "online" uevents to be
generated for ACPI containers after enumerating the container along
with all of its children.

Fixes: 46394fd0 (ACPI / hotplug: Move container-specific code out of the core)
Reported-and-tested-by: NYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: 3.14+ <stable@vger.kernel.org> # 3.14+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Newer laptops and tablets that use ACPI may have thermal sensors and
other devices with thermal control capabilities outside the core CPU/SOC,
for thermal safety reasons.
They are exposed for the OS to use via
1) INT3400 ACPI device object as the master.
2) INT3401 ~ INT340B ACPI device objects as the slaves.

This patch introduces a scan handler to enumerate the INT3400
ACPI device object to platform bus, and prevent its slaves
from being enumerated before the controller driver being probed.
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

The _SUN device indentification object is not guaranteed to return
the same value every time it is executed, so we should not cache its
return value, but rather execute it every time as needed.  If it is
cached, an incorrect stale value may be used in some situations.

This issue was exposed by commit 202317a5 (ACPI / scan: Add
acpi_device objects for all device nodes in the namespace).  Fix it
by avoiding to cache the return value of _SUN.

Fixes: 202317a5 (ACPI / scan: Add acpi_device objects for all device nodes in the namespace)
Signed-off-by: NYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: 3.14+ <stable@vger.kernel.org> # 3.14+
[ rjw: Changelog ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Currently, notify callbacks for fixed button events are run from
interrupt context.  That is not necessary and after commit 0bf6368e
(ACPI / button: Add ACPI Button event via netlink routine) it causes
netlink routines to be called from interrupt context which is not
correct.

Also, that is different from non-fixed device events (including
non-fixed button events) whose notify callbacks are all executed from
process context.

For the above reasons, make fixed button device notify callbacks run
in process context which will avoid the deadlock when using netlink
to report button events to user space.

Fixes: 0bf6368e (ACPI / button: Add ACPI Button event via netlink routine)
Link: https://lkml.org/lkml/2014/8/21/606Reported-by: NBenjamin Block <bebl@mageta.org>
Reported-by: NKnut Petersen <Knut_Petersen@t-online.de>
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
[rjw: Function names, subject and changelog.]
Cc: 3.15+ <stable@vger.kernel.org> # 3.15+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We generally don't allow ACPI drivers to bind to ACPI device objects
that companion "physical" device objects are created for to avoid
situations in which two different drivers may attempt to handle one
device at the same time.  Recent ACPI device enumeration rework
extended that approach to ACPI PNP devices by starting to use a scan
handler for enumerating them.  However, we previously allowed ACPI
drivers to bind to ACPI device objects with existing PNP device
companions and changing that led to functional regressions on some
systems.

For this reason, add a special check for PNP devices in
acpi_device_probe() so that ACPI drivers can bind to ACPI device
objects having existing PNP device companions as before.

Fixes: eec15edb (ACPI / PNP: use device ID list for PNPACPI device enumeration)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=81511
Link: https://bugzilla.kernel.org/show_bug.cgi?id=81971Reported-by: NGabriele Mazzotta <gabriele.mzt@gmail.com>
Reported-by: NDirk Griesbach <spamthis@freenet.de>
Cc: 3.16+ <stable@vger.kernel.org> # 3.16+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

When ACPI_HOTPLUG_MEMORY is not configured, memory_device_handler.attach
is not set.  In acpi_scan_attach_handler(), the acpi_device->handler will
not be initialized.

In acpi_scan_hot_remove(), it doesn't check if acpi_device->handler is NULL.
If we do memory hot-remove without ACPI_HOTPLUG_MEMORY configured, the kernel
will panic.

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000088
 IP: [<ffffffff813e318f>] acpi_device_hotplug+0x1d7/0x4c4
 PGD 0
 Oops: 0000 [#1] SMP
 Modules linked in: sd_mod(E) sr_mod(E) cdrom(E) crc_t10dif(E) crct10dif_common(E) ata_piix(E) libata(E)
 CPU: 0 PID: 41 Comm: kworker/u2:1 Tainted: G            E 3.16.0-rc7--3.16-rc7-tangchen+ #20
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
 Workqueue: kacpi_hotplug acpi_hotplug_work_fn
 task: ffff8800182436c0 ti: ffff880018254000 task.ti: ffff880018254000
 RIP: 0010:[<ffffffff813e318f>]  [<ffffffff813e318f>] acpi_device_hotplug+0x1d7/0x4c4
 RSP: 0000:ffff880018257da8  EFLAGS: 00000246
 RAX: 0000000000000000 RBX: ffff88001cd8d800 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: ffff88001e40e6f8 RDI: 0000000000000246
 RBP: ffff880018257df0 R08: 0000000000000096 R09: 00000000000011a0
 R10: 63735f6970636120 R11: 725f746f685f6e61 R12: 0000000000000003
 R13: ffff88001cc1c400 R14: ffff88001e062028 R15: 0000000000000040
 FS:  0000000000000000(0000) GS:ffff88001e400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
 CR2: 0000000000000088 CR3: 000000001a9a2000 CR4: 00000000000006f0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 0000000000000000 DR7: 0000000000000000
 Stack:
  00000000523cab58 ffff88001cd8d9f8 ffff88001852d480 00000000523cab58
  ffff88001852d480 ffff880018221e40 ffff88001cc1c400 ffff88001cce2d00
  0000000000000040 ffff880018257e08 ffffffff813dc31d ffff88001852d480
 Call Trace:
  [<ffffffff813dc31d>] acpi_hotplug_work_fn+0x1e/0x29
  [<ffffffff8108eefb>] process_one_work+0x17b/0x460
  [<ffffffff8108f69d>] worker_thread+0x11d/0x5b0
  [<ffffffff8108f580>] ? rescuer_thread+0x3a0/0x3a0
  [<ffffffff81096811>] kthread+0xe1/0x100
  [<ffffffff81096730>] ? kthread_create_on_node+0x1a0/0x1a0
  [<ffffffff816cc6bc>] ret_from_fork+0x7c/0xb0
  [<ffffffff81096730>] ? kthread_create_on_node+0x1a0/0x1a0

This patch fixes this problem by checking if acpi_device->handler is NULL
in acpi_scan_hot_remove().

Fixes: d22ddcbc (ACPI / hotplug: Add demand_offline hotplug profile flag)
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Cc: 3.14+ <stable@vger.kernel.org> # 3.14+
[rjw: Subject]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The ACPI device enumeration code in Linux assumes that buttons always
are wakeup devices, so it calls acpi_setup_gpe_for_wake() for them
which leads to undesirable side effects.  Namely, that function sets
up implicit device wake notification mechanism for a given GPE if
there is no handler method in the ACPI namespace, which from the
ACPICA's perspective means that there always is a way to handle
that GPE if enabled.  However, we don't handle wake notify events
for buttons, so if there are no handler methods for their GPEs in
the namespace, enabling a button GPE at run time leads to a GPE
storm in some cases (the GPE triggers, ACPICA carries out the
implicit wake notification for it which isn't handled, so the
GPE triggers again and so on).

To prevent that from happening use acpi_mark_gpe_for_wake()
instead of acpi_setup_gpe_for_wake() for buttons which will cause
ACPICA to only enable button GPEs if there are handler methods for
the in the namespace.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Since all of the acpi_set_hp_context() callers pass at least one NULL
function pointer and one caller passes NULL function pointers only
to it, drop function pointer arguments from acpi_set_hp_context()
and make the callers initialize the function pointers in struct
acpi_hotplug_context by themselves before passing it to
acpi_set_hp_context().
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>

Because of the growing demand for enumerating ACPI devices to
platform bus, change the code to enumerate ACPI device objects to
platform bus by default.  Namely, create platform devices for the
ACPI device objects that
 1. Have pnp.type.platform_id set (device objects with _HID currently).
 2. Do not have a scan handler attached.
 3. Are not SPI/I2C slave devices (that should be enumerated to the
    appropriate buses bus by their parent).
Signed-off-by: NZhang Rui <rui.zhang@intel.com>
[rjw: Subject and changelog, rebase and code cleanup]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>

Currently, some scan handlers can be compiled out entirely, which
leaves the device objects they normally attach to without a scan
handler.  This isn't a problem as long as we don't have any default
enumeration mechanism that applies to all devices without a scan
handler.  However, if such a default enumeration is added, it still
should not be applied to devices that are normally attached to by
scan handlers, because that may result in creating "physical" device
objects of a wrong type for them.

Since we are going to create platform device objects for all ACPI
device objects with pnp.type.platform_id set by default, clear
pnp.type.platform_id where there is a matching scan handler without
an .attach() callback and otherwise simply treat that scan handler
as though the .attach() callback was present but always returned 0.

This will allow us to compile out scan handler callbacks and leave
the device ID lists used by them so as to prevent creating platform
device objects for the matching ACPI devices.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>