Sometimes, the users may require a quirk to be provided from ACPI subsystem
core to prevent a GPE from flooding.
Normally, if a GPE cannot be dispatched, ACPICA core automatically prevents
the GPE from firing. But there are cases the GPE is dispatched by _Lxx/_Exx
provided via AML table, and OSPM is lacking of the knowledge to get
_Lxx/_Exx correctly executed to handle the GPE, thus the GPE flooding may
still occur.

The existing quirk mechanism can be enabled/disabled using the following
commands to prevent such kind of GPE flooding during runtime:
 # echo mask > /sys/firmware/acpi/interrupts/gpe00
 # echo unmask > /sys/firmware/acpi/interrupts/gpe00
To avoid GPE flooding during boot, we need a boot stage mechanism.

This patch provides such a boot stage quirk mechanism to stop this kind of
GPE flooding. This patch doesn't fix any feature gap but since the new
feature gaps could be found in the future endlessly, and can disappear if
the feature gaps are filled, providing a boot parameter rather than a DMI
table should suffice.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=53071
Link: https://bugzilla.kernel.org/show_bug.cgi?id=117481
Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/887793Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The introduction of acpi_dma_configure() allows to configure DMA
and related IOMMU for any device that is DMA capable. To achieve
that goal it ensures DMA masks are set-up to sane default values
before proceeding with IOMMU and DMA ops configuration.

On x86/ia64 systems, through acpi_bind_one(), acpi_dma_configure() is
called for every device that has an ACPI companion, in that every device
is considered DMA capable on x86/ia64 systems (ie acpi_get_dma_attr() API),
which has the side effect of initializing dma masks also for
pseudo-devices (eg CPUs and memory nodes) and potentially for devices
whose dma masks were not set-up before the acpi_dma_configure() API was
introduced, which may have noxious side effects.

Therefore, in preparation for IORT firmware specific DMA masks set-up,
wrap the default DMA masks set-up in acpi_dma_configure() inside an IORT
specific wrapper that reverts to a NOP on x86/ia64 systems, restoring the
default expected behaviour on x86/ia64 systems and keeping DMA default
masks set-up on IORT based (ie ARM) arch configurations.
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NHanjun Guo <hanjun.guo@linaro.org>
Tested-by: NHanjun Guo <hanjun.guo@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
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>
Cc: Sricharan R <sricharan@codeaurora.org>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Starting from ACPI spec 3.0, it's only clarified that _BCM control
method is required if _BCL is implemented. There is no word
saying _BQC is required.

And in ACPI spec 6.1 B.5.4, for _BQC, it is explicitly stated that
"This optional method returns the current brightness level of a
built-in display output device. If present, it must be set by
the platform for initial brightness."

Thus remove the obsolete warning message.
Signed-off-by: NZhang Rui <rui.zhang@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

DT based systems have a generic kernel API to configure IOMMUs
for devices (ie of_iommu_configure()).

On ARM based ACPI systems, the of_iommu_configure() equivalent can
be implemented atop ACPI IORT kernel API, with the corresponding
functions to map device identifiers to IOMMUs and retrieve the
corresponding IOMMU operations necessary for DMA operations set-up.

By relying on the iommu_fwspec generic kernel infrastructure,
implement the IORT based IOMMU configuration for ARM ACPI systems
and hook it up in the ACPI kernel layer that implements DMA
configuration for a device.
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [ACPI core]
Reviewed-by: NTomasz Nowicki <tn@semihalf.com>
Tested-by: NHanjun Guo <hanjun.guo@linaro.org>
Tested-by: NTomasz Nowicki <tn@semihalf.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Tomasz Nowicki <tn@semihalf.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

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: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> [pci]
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NTomasz Nowicki <tn@semihalf.com>
Tested-by: NHanjun Guo <hanjun.guo@linaro.org>
Tested-by: NTomasz 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: NWill Deacon <will.deacon@arm.com>

We have a couple of drivers, acpi_apd.c and acpi_lpss.c,
that need to pass extra build-in properties to the devices
they create. Previously the drivers added those properties
to the struct device which is member of the struct
acpi_device, but that does not work. Those properties need
to be assigned to the struct device of the platform device
instead in order for them to become available to the
drivers.

To fix this, this patch changes acpi_create_platform_device
function to take struct property_entry pointer as parameter.

Fixes: 20a875e2 (serial: 8250_dw: Add quirk for APM X-Gene SoC)
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: NYazen Ghannam <yazen.ghannam@amd.com>
Tested-by: NJérôme de Bretagne <jerome.debretagne@gmail.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Starting from Intel Skylake the iTCO watchdog timer registers were moved to
reside in the same register space with SMBus host controller.  Not all
needed registers are available though and we need to unhide P2SB (Primary
to Sideband) device briefly to be able to read status of required NO_REBOOT
bit. The i2c-i801.c SMBus driver used to handle this and creation of the
iTCO watchdog platform device.

Windows, on the other hand, does not use the iTCO watchdog hardware
directly even if it is available. Instead it relies on ACPI Watchdog Action
Table (WDAT) table to describe the watchdog hardware to the OS. This table
contains necessary information about the the hardware and also set of
actions which are executed by a driver as needed.

This patch implements a new watchdog driver that takes advantage of the
ACPI WDAT table. We split the functionality into two parts: first part
enumerates the WDAT table and if found, populates resources and creates
platform device for the actual driver. The second part is the driver
itself.

The reason for the split is that this way we can make the driver itself to
be a module and loaded automatically if the WDAT table is found. Otherwise
the module is not loaded.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

It is possible to register _Qxx from namespace and use the ECDT EC to
perform event handling. The reported bug reveals that Windows is using ECDT
in this way in case the namespace EC is not present. This patch facilitates
Linux to support ECDT in this way.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=115021Reported-and-tested-by: NLuya Tshimbalanga <luya@fedoraproject.org>
Tested-by: NJonh Henderson <jw.hendy@gmail.com>
Reviewed-by: NPeter Wu <peter@lekensteyn.nl>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit e647b532 ("ACPI: Add early device probing infrastructure")
introduced code that allows inserting driver specific
struct acpi_probe_entry probe entries into ACPI linker sections
(one per-subsystem, eg irqchip, clocksource) that are then walked
to retrieve the data and function hooks required to probe the
respective kernel components.

Probing for all entries in a section is triggered through
the __acpi_probe_device_table() function, that in turn, according
to the table ID a given probe entry reports parses the table
with the function retrieved from the respective section structures
(ie struct acpi_probe_entry). Owing to the current ACPI table
parsing implementation, the __acpi_probe_device_table() function
has to share global variables with the acpi_match_madt() function, so
in order to guarantee mutual exclusion locking is required
between the two functions.

Current kernel code implements the locking through the acpi_probe_lock
spinlock; this has the side effect of requiring all code called
within the lock (ie struct acpi_probe_entry.probe_{table/subtbl} hooks)
not to sleep.

However, kernel subsystems that make use of the early probing
infrastructure are relying on kernel APIs that may sleep (eg
irq_domain_alloc_fwnode(), among others) in the function calls
pointed at by struct acpi_probe_entry.{probe_table/subtbl} entries
(eg gic_v2_acpi_init()), which is a bug.

Since __acpi_probe_device_table() is called from context
that is allowed to sleep the acpi_probe_lock spinlock can be replaced
with a mutex; this fixes the issue whilst still guaranteeing
mutual exclusion.
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Fixes: e647b532 (ACPI: Add early device probing infrastructure)
Cc: 4.4+ <stable@vger.kernel.org> # 4.4+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Add support for ACPI reconfiguration notifiers to allow subsystems
to react to changes in the ACPI tables that happen after the initial
enumeration. This is similar with the way dynamic device tree
notifications work.

The reconfigure notifications supported for now are device add and
device remove.

Since ACPICA allows only one table notification handler, this patch
makes the table notifier function generic and moves it out of the
sysfs specific code.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

If the ACPI tables change as a result of a dinamically loaded table
and a bus rescan is required the enumeration/visited flag are not
consistent.

I2C/SPI are not directly enumerated in acpi_bus_attach(), however
the visited flag is set. This makes it impossible to check if an
ACPI device has already been enumerated by the I2C and SPI
subsystems. To fix this issue we only set the visited flags if
the device is not I2C or SPI.

With this change we also need to remove setting visited to false
from acpi_bus_attach(), otherwise if we rescan already enumerated
I2C/SPI devices we try to re-enumerate them.

Note that I2C/SPI devices can be enumerated either via a scan handler
(when using PRP0001) or via regular device_attach(). In either case
the flow goes through acpi_default_enumeration() which makes it the
ideal place to mark the ACPI device as enumerated.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI 6.0 introduces a new table STAO to list the devices which are used
by Xen and can't be used by Dom0. On Xen virtual platforms, the physical
UART is used by Xen. So here it hides UART from Dom0.

CC: "Rafael J. Wysocki" <rjw@rjwysocki.net> (supporter:ACPI)
CC: Len Brown <lenb@kernel.org> (supporter:ACPI)
CC: linux-acpi@vger.kernel.org (open list:ACPI)
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

On ARM64 some devices use the AMBA device and not the platform bus for
probing so add support for this. Uses a dummy clock for apb_pclk as ACPI
does not have a suitable clock representation and to keep the core
AMBA bus code unchanged between probing methods.
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NGraeme Gregory <graeme.gregory@linaro.org>
Signed-off-by: NAleksey Makarov <aleksey.makarov@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There's an idiom in use by 7 Linux drivers to detect the presence of a
particular ACPI HID by walking the namespace with acpi_get_devices().
The callback passed to acpi_get_devices() is mostly identical across
the drivers, leading to lots of duplicate code.

Add acpi_dev_present(), the ACPI equivalent to pci_dev_present(),
allowing us to deduplicate all that boilerplate in the drivers.
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Reviewed-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

acpi_device_add() allocates and adds an element to acpi_bus_id_list
(or increments the instance count if the device's HID is already
present in the list), but the element is never deleted from the list
nor freed. Fix it.
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Some ACPI node's _STA will touch operation region field, since the
evaluation of _STA in acpi_bus_type_and_status is very early, the
operation region handler is not ready yet. Instead of fail that function
and not creating the acpi_device node consequently, set status to 0 so
that later when the driver for that device is probing, it can find
the acpi_device node and proceed normally. And at that time, the
handler for the operation region is ready and its _STA evaluation will
succeed, its present status can be checked there.

Even there will be no driver using this node later, it doesn't seem
hurt to have one more acpi_device node created with status set to 0.

This happens on Microsoft Surface 3, where the SPI device node NTRG's
_STA touches GPIO fields and the SPI core driver will only enumerate SPI
devices from ACPI if the acpi_device node is 1: created; 2: _STA
indicates it's present.

Note that due to another problem in SPI driver, for NTRG to be actually
enumerated, some changes have to be made in the SPI layer, which is
addressed by Mika(not send out yet):
https://bugzilla.kernel.org/show_bug.cgi?id=104291#c23

Link: https://bugzilla.kernel.org/show_bug.cgi?id=104291Reported-by: NBastien Nocera <bugzilla@hadess.net>
Signed-off-by: NAaron Lu <aaron.lu@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Adding acpi_get_dma_attr() to query DMA attributes of ACPI devices.
It returns the enum dev_dma_attr, which communicates DMA information
more clearly. This API replaces the acpi_check_dma(), which will be
removed in subsequent patch.

This patch also provides a convenient function, acpi_dma_supported(),
to check DMA support of the specified ACPI device.
Signed-off-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

IRQ controllers and timers are the two types of device the kernel
requires before being able to use the device driver model.

ACPI so far lacks a proper probing infrastructure similar to the one
we have with DT, where we're able to declare IRQ chips and
clocksources inside the driver code, and let the core code pick it up
and call us back on a match. This leads to all kind of really ugly
hacks all over the arm64 code and even in the ACPI layer.

In order to allow some basic probing based on the ACPI tables,
introduce "struct acpi_probe_entry" which contains just enough
data and callbacks to match a table, an optional subtable, and
call a probe function. A driver can, at build time, register itself
and expect being called if the right entry exists in the ACPI
table.

A acpi_probe_device_table() is provided, taking an identifier for
a set of acpi_prove_entries, and iterating over the registered
entries.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Reviewed-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NHanjun Guo <hanjun.guo@linaro.org>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Empirically, acpi_add_id is mostly called with string literals, so
using kstrdup_const for initializing struct acpi_hardware_id::id saves
a little run-time memory and a string copy.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This is preparation for using kstrdup_const to initialize that member.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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>