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>

Commit 73f7d1ca "ACPI / init: Run acpi_early_init() before
timekeeping_init()" moved the ACPI subsystem initialization,
including the ACPI mode enabling, to an earlier point in the
initialization sequence, to allow the timekeeping subsystem
use ACPI early.  Unfortunately, that resulted in boot regressions
on some systems and the early ACPI initialization was moved toward
its original position in the kernel initialization code by commit
c4e1acbb "ACPI / init: Invoke early ACPI initialization later".

However, that turns out to be insufficient, as boot is still broken
on the Tyan S8812 mainboard.

To fix that issue, split the ACPI early initialization code into
two pieces so the majority of it still located in acpi_early_init()
and the part switching over the platform into the ACPI mode goes into
a new function, acpi_subsystem_init(), executed at the original early
ACPI initialization spot.

That fixes the Tyan S8812 boot problem, but still allows ACPI
tables to be loaded earlier which is useful to the EFI code in
efi_enter_virtual_mode().

Link: https://bugzilla.kernel.org/show_bug.cgi?id=97141
Fixes: 73f7d1ca "ACPI / init: Run acpi_early_init() before timekeeping_init()"
Reported-and-tested-by: NMarius Tolzmann <tolzmann@molgen.mpg.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NToshi Kani <toshi.kani@hp.com>
Reviewed-by: NHanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: NLee, Chun-Yi <jlee@suse.com>

Introduce ACPI_IRQ_MODEL_GIC which is needed for ARM64 as GIC is
used, and then register device's gsi with the core IRQ subsystem.

acpi_register_gsi() is similar to DT based irq_of_parse_and_map(),
since gsi is unique in the system, so use hwirq number directly
for the mapping.

We are going to implement stacked domains when GICv2m, GICv3, ITS
support are added.

CC: Marc Zyngier <marc.zyngier@arm.com>
Originally-by: NAmit Daniel Kachhap <amit.daniel@samsung.com>
Tested-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Tested-by: NYijing Wang <wangyijing@huawei.com>
Tested-by: NMark Langsdorf <mlangsdo@redhat.com>
Tested-by: NJon Masters <jcm@redhat.com>
Tested-by: NTimur Tabi <timur@codeaurora.org>
Tested-by: NRobert Richter <rrichter@cavium.com>
Acked-by: NRobert Richter <rrichter@cavium.com>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NGrant Likely <grant.likely@linaro.org>
Signed-off-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Revert parts of f244d8b6 ("ACPIPHP / radeon / nouveau: Fix VGA
switcheroo problem related to hotplug").

A previous commit 5493b31f0b55 ("PCI: Add pci_ignore_hotplug() to ignore
hotplug events for a device") added equivalent functionality implemented in
a different way for both acpiphp and pciehp.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NDave Airlie <airlied@redhat.com>
Acked-by: NRajat Jain <rajatxjain@gmail.com>

There are global variables and functions not upstreamed to the ACPICA code
base.  Such symbols still can be referenced by external users as they are
listed in the acpixf.h.  This patch uses ACPI_GLOBAL and
ACPI_EXTERNAL_RETURN_STATUS mechanism to add stub support for such symbols.
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The following warning message is triggered:
 WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:136 __early_ioremap+0x11f/0x1f2()
 Modules linked in:
 CPU: 0 PID: 0 Comm: swapper Not tainted 3.15.0-rc1-00017-g86dfc6f3-dirty #298
 Hardware name: Intel Corporation S2600CP/S2600CP, BIOS SE5C600.86B.99.99.x036.091920111209 09/19/2011
  0000000000000009 ffffffff81b75c40 ffffffff817c627b 0000000000000000
  ffffffff81b75c78 ffffffff81067b5d 000000000000007b 8000000000000563
  00000000b96b20dc 0000000000000001 ffffffffff300e0c ffffffff81b75c88
 Call Trace:
  [<ffffffff817c627b>] dump_stack+0x45/0x56
  [<ffffffff81067b5d>] warn_slowpath_common+0x7d/0xa0
  [<ffffffff81067c3a>] warn_slowpath_null+0x1a/0x20
  [<ffffffff81d4b9d5>] __early_ioremap+0x11f/0x1f2
  [<ffffffff81d4bc5b>] early_ioremap+0x13/0x15
  [<ffffffff81d2b8f3>] __acpi_map_table+0x13/0x18
  [<ffffffff817b8d1a>] acpi_os_map_memory+0x26/0x14e
  [<ffffffff813ff018>] acpi_tb_acquire_table+0x42/0x70
  [<ffffffff813ff086>] acpi_tb_validate_table+0x27/0x37
  [<ffffffff813ff0e5>] acpi_tb_verify_table+0x22/0xd8
  [<ffffffff813ff6a8>] acpi_tb_install_non_fixed_table+0x60/0x1c9
  [<ffffffff81d61024>] acpi_tb_parse_root_table+0x218/0x26a
  [<ffffffff81d1b120>] ? early_idt_handlers+0x120/0x120
  [<ffffffff81d610cd>] acpi_initialize_tables+0x57/0x59
  [<ffffffff81d5f25d>] acpi_table_init+0x1b/0x99
  [<ffffffff81d2bca0>] acpi_boot_table_init+0x1e/0x85
  [<ffffffff81d23043>] setup_arch+0x99d/0xcc6
  [<ffffffff81d1b120>] ? early_idt_handlers+0x120/0x120
  [<ffffffff81d1bbbe>] start_kernel+0x8b/0x415
  [<ffffffff81d1b120>] ? early_idt_handlers+0x120/0x120
  [<ffffffff81d1b5ee>] x86_64_start_reservations+0x2a/0x2c
  [<ffffffff81d1b72e>] x86_64_start_kernel+0x13e/0x14d
 ---[ end trace 11ae599a1898f4e7 ]---
when installing the following table during early stage:
 ACPI: SSDT 0x00000000B9638018 07A0C4 (v02 INTEL  S2600CP  00004000 INTL 20100331)
The regression is caused by the size limitation of the x86 early IO mapping.

The root cause is:
 1. ACPICA doesn't split IO memory mapping and table mapping;
 2. Linux x86 OSL implements acpi_os_map_memory() using a size limited fix-map
    mechanism during early boot stage, which is more suitable for only IO
    mappings.

This patch fixes this issue by utilizing acpi_gbl_verify_table_checksum to
disable the table mapping during early stage and enabling it again for the
late stage. In this way, the normal code path is not affected. Then after
the code related to the root cause is cleaned up, the early checksum
verification can be easily re-enabled.

A new boot parameter - acpi_force_table_verification is introduced for
the platforms that require the checksum verification to stop loading bad
tables.

This fix also covers the checksum verification for the table overrides. Now
large tables can also be overridden using the initrd override mechanism.
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Reported-and-tested-by: NYuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There is already acpi_bus_get_private_data() to get ACPI handle data
which is associated with acpi_bus_private_data_handler(). This patch
is to add acpi_bus_attach_private_data() to make a pair and facilitate
to attach and get data to/from ACPI handle.
Reviewed-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>

This patch fixes the following issue:
If DSDT is customized, no local DSDT copy is needed.

References: https://bugzilla.kernel.org/show_bug.cgi?id=69711Signed-off-by: NEnrico Etxe Arte <goitizena.generoa@gmail.com>
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Cc: 2.6.35+ <stable@vger.kernel.org> # 2.6.35+
[rjw: Subject]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Make the handling of hotplug events in acpi_bus_notify() slightly
cleaner by using an extra local variable to indicate when
acpi_hotplug_schedule() should be called.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 1a699476 "ACPI / hotplug / PCI: Hotplug notifications from
acpi_bus_notify()" changed the root notify handler, acpi_bus_notify(),
to block unknown type norifications, but it overlooked the fact that
they might be propagated to drivers via the ->notify() callback.

Fix the problem by allowing drivers to receive unknown type
notifications via ->notify() as before.

Fixes: 1a699476 (ACPI / hotplug / PCI: Hotplug notifications from acpi_bus_notify())
Reported-and-tested-by: NMantas Mikulėnas <grawity@gmail.com>
Reported-and-tested-by: NSitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Since the only function executed by acpi_hotplug_execute() is
acpi_device_hotplug() and it only is called by the ACPI core,
simplify its definition so that it only takes two arguments, the
ACPI device object pointer and event code, rename it to
acpi_hotplug_schedule() and move its header from acpi_bus.h to
the ACPI core's internal header file internal.h.  Modify the
definition of acpi_device_hotplug() so that its first argument is
an ACPI device object pointer and modify the definition of
struct acpi_hp_work accordingly.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NToshi Kani <toshi.kani@hp.com>

Replace acpi_evaluate_hotplug_ost() with acpi_evaluate_ost()
everywhere and drop the ACPI_HOTPLUG_OST symbol so that hotplug
_OST is supported unconditionally.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NToshi Kani <toshi.kani@hp.com>

Since acpi_bus_notify() is executed on all notifications for all
devices anyway, make it execute acpi_device_hotplug() for all
hotplug events instead of installing notify handlers pointing to
the same function for all hotplug devices.

This change reduces both the size and complexity of ACPI-based device
hotplug code.  Moreover, since acpi_device_hotplug() only does
significant things for devices that have either an ACPI scan handler,
or a hotplug context with .eject() defined, and those devices
had notify handlers pointing to acpi_hotplug_notify_cb() installed
before anyway, this modification shouldn't change functionality.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There is a slight possibility for the ACPI device object pointed to
by adev in acpi_hotplug_notify_cb() to become invalid between the
acpi_bus_get_device() that it comes from and the subsequent dereference
of that pointer under get_device().  Namely, if acpi_scan_drop_device()
runs in parallel with acpi_hotplug_notify_cb(), acpi_device_del_work_fn()
queued up by it may delete the device object in question right after
a successful execution of acpi_bus_get_device() in acpi_bus_notify().

An analogous problem is present in acpi_bus_notify() where the device
pointer coming from acpi_bus_get_device() may become invalid before
it subsequent dereference in the "if" block.

To prevent that from happening, introduce a new function,
acpi_bus_get_acpi_device(), working analogously to acpi_bus_get_device()
except that it will grab a reference to the ACPI device object returned
by it and it will do that under the ACPICA's namespace mutex.  Then,
make both acpi_hotplug_notify_cb() and acpi_bus_notify() use
acpi_bus_get_acpi_device() instead of acpi_bus_get_device() so as to
ensure that the pointers used by them will not become stale at one
point.

In addition to that, introduce acpi_bus_put_acpi_device() as a wrapper
around put_device() to be used along with acpi_bus_get_acpi_device()
and make the (new) users of the latter use acpi_bus_put_acpi_device()
too.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>

There is currently no facility in ACPI to express the hookup of voltage
regulators, the expectation is that the regulators that exist in the
system will be handled transparently by firmware if they need software
control at all. This means that if for some reason the regulator API is
enabled on such a system it should assume that any supplies that devices
need are provided by the system at all relevant times without any software
intervention.

Tell the regulator core to make this assumption by calling
regulator_has_full_constraints(). Do this as soon as we know we are using
ACPI so that the information is available to the regulator core as early
as possible. This will cause the regulator core to pretend that there is
an always on regulator supplying any supply that is requested but that has
not otherwise been mapped which is the behaviour expected on a system with
ACPI.

Should the ability to specify regulators be added in future revisions of
ACPI then once we have support for ACPI mappings in the kernel the same
assumptions will apply. It is also likely that systems will default to a
mode of operation which does not require any interpretation of these
mappings in order to be compatible with existing operating system releases
so it should remain safe to make these assumptions even if the mappings
exist but are not supported by the kernel.
Signed-off-by: NMark Brown <broonie@linaro.org>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The changes in the ACPI-based PCI hotplug (ACPIPHP) subsystem made
during the 3.12 development cycle uncovered a problem with VGA
switcheroo that on some systems, when the device-specific method
(ATPX in the radeon case, _DSM in the nouveau case) is used to turn
off the discrete graphics, the BIOS generates ACPI hotplug events for
that device and those events cause ACPIPHP to attempt to remove the
device from the system (they are events for a device that was present
previously and is not present any more, so that's what should be done
according to the spec).  Then, the system stops functioning correctly.

Since the hotplug events in question were simply silently ignored
previously, the least intrusive way to address that problem is to
make ACPIPHP ignore them again.  For this purpose, introduce a new
ACPI device flag, no_hotplug, and modify ACPIPHP to ignore hotplug
events for PCI devices whose ACPI companions have that flag set.
Next, make the radeon and nouveau switcheroo detection code set the
no_hotplug flag for the discrete graphics' ACPI companion.

Fixes: bbd34fcd (ACPI / hotplug / PCI: Register all devices under the given bridge)
References: https://bugzilla.kernel.org/show_bug.cgi?id=61891
References: https://bugzilla.kernel.org/show_bug.cgi?id=64891Reported-and-tested-by: NMike Lothian <mike@fireburn.co.uk>
Reported-and-tested-by: <madcatx@atlas.cz>
Reported-and-tested-by: NJoaquín Aramendía <samsagax@gmail.com>
Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 3.12+ <stable@vger.kernel.org> # 3.12+

Replace direct inclusions of <acpi/acpi.h>, <acpi/acpi_bus.h> and
<acpi/acpi_drivers.h>, which are incorrect, with <linux/acpi.h>
inclusions and remove some inclusions of those files that aren't
necessary.

First of all, <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h>
should not be included directly from any files that are built for
CONFIG_ACPI unset, because that generally leads to build warnings about
undefined symbols in !CONFIG_ACPI builds.  For CONFIG_ACPI set,
<linux/acpi.h> includes those files and for CONFIG_ACPI unset it
provides stub ACPI symbols to be used in that case.

Second, there are ordering dependencies between those files that always
have to be met.  Namely, it is required that <acpi/acpi_bus.h> be included
prior to <acpi/acpi_drivers.h> so that the acpi_pci_root declarations the
latter depends on are always there.  And <acpi/acpi.h> which provides
basic ACPICA type declarations should always be included prior to any other
ACPI headers in CONFIG_ACPI builds.  That also is taken care of including
<linux/acpi.h> as appropriate.
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci stuff)
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> (Xen stuff)
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Introduce a static inline function for setting the status field
of struct acpi_device on the basis of a supplied u32 number,
acpi_set_device_status(), and use it instead of the horrible
horrible STRUCT_TO_INT() macro wherever applicable.  Having done
that, drop STRUCT_TO_INT() (and pretend that it has never existed).
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>

There are two global hotplug notification handling routines in bus.c,
acpi_bus_check_device() and acpi_bus_check_scope(), that have never
been finished and don't do anything useful, so drop them.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This H/W error log driver (a.k.a eMCA driver) is implemented based on
http://www.intel.com/content/www/us/en/architecture-and-technology/enhanced-mca-logging-xeon-paper.html

After errors are captured, more detailed platform specific information
can be got via this new enhanced H/W error log driver. Most notably we
can track memory errors back to the DIMM slot silk screen label.
Signed-off-by: NChen, Gong <gong.chen@linux.intel.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

OSC_QUERY_TYPE isn't a "type"; it's an index into the _OSC Capabilities
Buffer of DWORDs.  Rename OSC_QUERY_TYPE, OSC_SUPPORT_TYPE, and
OSC_CONTROL_TYPE to OSC_QUERY_DWORD, etc., to make this clear.
No functional change.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Move acpi_bus_get_device() from bus.c to scan.c which allows
acpi_bus_data_handler() to become static and clean up the latter.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This patch cleans up the following sparse warning:

# make C=2 drivers/acpi/osl.o
...
drivers/acpi/osl.c:1775:20: warning: symbol 'acpi_os_initialize1' was not declared. Should it be static?
...
  CC      drivers/acpi/osl.o
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

It is quite some time that this one has been deprecated.
Get rid of it.

Should some really important user be overseen, it may be reverted and
the userspace program worked on first, but it is time to do something
to get rid of this old stuff...
Signed-off-by: NThomas Renninger <trenn@suse.de>
Acked-by: NMatthew Garrett <matthew.garrett@nebula.com>
Acked-by: NHenrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There are no users of the ACPI bus notifier call chain,
acpi_bus_notify_list, any more, so drop it.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Introduce helper function acpi_execute_simple_method() and use it in
a number of places to simplify code.

[rjw: Changelog]
Signed-off-by: NJiang Liu <jiang.liu@huawei.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

These local variables are all initialized at their first use, so there's
no point in initializing them earlier.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Replace the combination of kmalloc() and memcpy() in acpi_run_osc()
with a single call to kmemdup().

[rjw: Changelog]
Signed-off-by: NAndrei Epure <epure.andrei@gmail.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Move ACPI device power management functions from drivers/acpi/bus.c
to drivers/acpi/device_pm.c.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The function returning string representations of ACPI device power
states, state_string((), is now static, because it is only used
internally in drivers/acpi/bus.c.  However, it will be used outside
of that file going forward, so rename it to
acpi_power_state_string(), add a kerneldoc comment to it and add its
header to acpi_bus.h.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The function used for retrieving ACPI device power states,
__acpi_bus_get_power(), is now static, because it is only used
internally in drivers/acpi/bus.c.  However, it will be used
outside of that file going forward, so rename it to
acpi_device_get_power(), in analogy with acpi_device_set_power(),
add a kerneldoc comment to it and add its header to acpi_bus.h.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

During power transitions into D3cold from any shallower power states
we are supposed to transition the device into D3hot and remove power
from it afterward, but the current code in acpi_device_set_power()
doesn't work this way.

At the same time, though, we need to be careful enough to preserve
backwards compatibility for systems that don't distinguish between
D3hot and D3cold (e.g. designed before ACPI 4).

Modify acpi_device_set_power() so that it works in accordance with
the expectations in both cases.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

No power transitioning from D3 state up to a non-D0 state is allowed
so make acpi_device_set_power() fail and complain if such a transition
is attempted.
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

If the caller of acpi_bus_set_power() already has a pointer to the
struct acpi_device object corresponding to the device in question, it
doesn't make sense for it to go through acpi_bus_get_device(), which
may be costly, because it involves acquiring the global ACPI
namespace mutex.

For this reason, export the function operating on struct acpi_device
objects used internally by acpi_bus_set_power(), so that it may be
called instead of acpi_bus_set_power() in the above case, and change
its name to acpi_device_set_power().

Additionally, introduce two inline wrappers for checking ACPI PM
capabilities of devices represented by struct acpi_device objects.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The _OSC method may exist in module level code,
so it must be called after ACPI_FULL_INITIALIZATION

On some new platforms with Zero-Power-Optical-Disk-Drive (ZPODD)
support, this fix is necessary to save power.
Signed-off-by: NLin Ming <ming.m.lin@intel.com>
Tested-by: NAaron Lu <aaron.lu@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>
Cc: stable@vger.kernel.org

It turns out that there are ACPI BIOSes defining device objects with
_PSx and without either _PSC or _PRx.  For devices corresponding to
those ACPI objetcs __acpi_bus_get_power() returns ACPI_STATE_UNKNOWN
and their initial power states are regarded as unknown as a result.
If such a device is a parent of another power-manageable device, the
child cannot be put into a low-power state through ACPI, because
__acpi_bus_set_power() refuses to change power states of devices
whose parents' power states are unknown.

To work around this problem, observe that the ACPI power state of
a device cannot be higher-power (lower-number) than the power state
of its parent.  Thus, if the device's _PSC method or the
configuration of its power resources indicates that the device is
in D0, the device's parent has to be in D0 as well.  Consequently,
if the parent's power state is unknown when we've just learned that
its child's power state is D0, we can safely set the parent's
power.state field to ACPI_STATE_D0.
Tested-by: NAaron Lu <aaron.lu@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

When ACPI_HOTPLUG_OST is defined, set hotplug _OST support bit
OSC_SB_HOTPLUG_OST_SUPPORT to indicate that the OS supports hotplug
_OST by calling the platform-wide ACPI Operating System Capabilities
(_OSC).
Signed-off-by: NToshi Kani <toshi.kani@hp.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

After recent changes of the ACPI device power states definitions, if
power resources are not used for the device's power management, the
state returned by __acpi_bus_get_power() cannot exceed D3hot, because
the return values of _PSC are 0 through 3.  However, if the _PR3
method is not present for the device and _PS3 returns 3, we have to
assume that the device is in D3cold, so the value returned by
__acpi_bus_get_power() in that case should be 4.

Similarly, acpi_power_get_inferred_state() should take the power
resources for the D3hot state into account in general, so that it
can return 3 if those resources are "on" or 4 (D3cold) otherwise.

Fix the the above two issues and make sure that if both _PSC and
_PR3 are present for the device, the power resources listed by _PR3
will be used to determine if the number 3 returned by _PSC is meant
to represent D3cold or D3hot.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>