ACPI: s2idle: Add a new ->check() callback for platform_s2idle_ops

On some platforms it is found that Linux more aggressively enters s2idle
than Windows enters Modern Standby and this uncovers some synchronization
issues for the platform. To aid in debugging this class of problems in
the future, add support for an extra optional callback intended for
drivers to emit extra debugging.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20220829162953.5947-2-mario.limonciello@amd.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Revert "Revert "ACPI: scan: Turn off unused power resources during initialization""

Revert commit 5db91e9cb5b3 ("Revert "ACPI: scan: Turn off unused
power resources during initialization") which was not necessary.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Revert "ACPI: scan: Turn off unused power resources during initialization"

Revert commit 4b9ee772eaa8 ("ACPI: scan: Turn off unused power
resources during initialization") that is reported to cause
initialization issues to occur.

Reported-by: Shujun Wang <wsj20369@163.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI: scan: Turn off unused power resources during initialization

It is reported that on certain platforms there are power resources
that are not associated with any devices physically present in the
platform. Those power resources are expected to be turned off by
the OS in accordance with the ACPI specification (section 7.3 of
ACPI 6.4) which currently is not done by Linux and that may lead
to obscure issues.

For instance, leaving those power resources in the "on" state may
prevent the platform from reaching the lowest power state in
suspend-to-idle which leads to excessive power draw.

For this reason, turn all of the unused ACPI power resources off
at the end of the initial namespace scan for devices in analogy with
resume from suspend-to-RAM.

Link: https://uefi.org/specs/ACPI/6.4/07_Power_and_Performance_Mgmt/device-power-management-objects.html
Reported-by: David Box <david.e.box@linux.intel.com>
Tested-by: Wendy Wang <wendy.wang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI: PM: s2idle: Move x86-specific code to the x86 directory

Some code in drivers/acpi/sleep.c (which is regarded as a generic
file) related to suspend-to-idle support has grown direct dependencies
on x86, but in fact it has been specific to x86 (which is the only
user of it) anyway for a long time.

For this reason, move that code to a separate file under acpi/x86/
and make it build and run as before under the right conditions.

While at it, rename a vendor checking function in that code and
consistently use acpi_handle_debug() for printing debug-related
information in it.

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI: PM: Add acpi_[un]register_wakeup_handler()

Since commit fdde0ff8590b ("ACPI: PM: s2idle: Prevent spurious SCIs from
waking up the system") the SCI triggering without there being a wakeup
cause recognized by the ACPI sleep code will no longer wakeup the system.

This works as intended, but this is a problem for devices where the SCI
is shared with another device which is also a wakeup source.

In the past these, from the pov of the ACPI sleep code, spurious SCIs
would still cause a wakeup so the wakeup from the device sharing the
interrupt would actually wakeup the system. This now no longer works.

This is a problem on e.g. Bay Trail-T and Cherry Trail devices where
some peripherals (typically the XHCI controller) can signal a
Power Management Event (PME) to the Power Management Controller (PMC)
to wakeup the system, this uses the same interrupt as the SCI.
These wakeups are handled through a special INT0002 ACPI device which
checks for events in the GPE0a_STS for this and takes care of acking
the PME so that the shared interrupt stops triggering.

The change to the ACPI sleep code to ignore the spurious SCI, causes
the system to no longer wakeup on these PME events. To make things
worse this means that the INT0002 device driver interrupt handler will
no longer run, causing the PME to not get cleared and resulting in the
system hanging. Trying to wakeup the system after such a PME through e.g.
the power button no longer works.

Add an acpi_register_wakeup_handler() function which registers
a handler to be called from acpi_s2idle_wake() and when the handler
returns true, return true from acpi_s2idle_wake().

The INT0002 driver will use this mechanism to check the GPE0a_STS
register from acpi_s2idle_wake() and to tell the system to wakeup
if a PME is signaled in the register.

Fixes: fdde0ff8590b ("ACPI: PM: s2idle: Prevent spurious SCIs from waking up the system")
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ACPI / power: Delay turning off unused power resources after suspend

Commit 660b1113e0f3 (ACPI / PM: Fix consistency check for power resources
during resume) introduced a check for ACPI power resources which have
been turned on by the BIOS during suspend and turns these back off again.

This is causing problems on a Dell Venue Pro 11 7130 (i5-4300Y) it causes
the following messages to show up in dmesg:

[ 131.014605] ACPI: Waking up from system sleep state S3
[ 131.150271] acpi LNXPOWER:07: Turning OFF
[ 131.150323] acpi LNXPOWER:06: Turning OFF
[ 131.150911] acpi LNXPOWER:00: Turning OFF
[ 131.169014] ACPI : EC: interrupt unblocked
[ 131.181811] xhci_hcd 0000:00:14.0: System wakeup disabled by ACPI
[ 133.535728] pci_raw_set_power_state: 76 callbacks suppressed
[ 133.535735] iwlwifi 0000:01:00.0: Refused to change power state,
currently in D3
[ 133.597672] PM: noirq resume of devices complete after 2428.891 msecs

Followed by a bunch of iwlwifi errors later on and the pcie device
dropping from the bus (acpiphp thinks it has been unplugged).

Disabling the turning off of unused power resources fixes this. Instead
of adding a quirk for this system, this commit fixes this by moving the
disabling of unused power resources to later in the resume sequence
when the iwlwifi card has been moved out of D3 so the ref_count for
its power resource no longer is 0.

This new behavior seems to match the intend of the original commit which
commit-msg says: "(... which means that no devices are going to need them
any time soon) and we should turn them off".

This also avoids power resources which we need when bringing devices out
of D3 from getting bounced off and then back on again.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPICA: Drop Linux-specific waking vector functions

Commit f06147f9fbf1 (ACPICA: Hardware: Enable firmware waking vector
for both 32-bit and 64-bit FACS) added three functions that aren't
present in upstream ACPICA, acpi_hw_set_firmware_waking_vectors(),
acpi_set_firmware_waking_vectors() and acpi_set_firmware_waking_vector64(),
to allow Linux to use the previously existing API for setting the
platform firmware waking vector.

However, that wasn't necessary, since the ACPI sleep support code
in Linux can be modified to use the upstream ACPICA's API easily
and the additional functions may be dropped which reduces the code
size and puts the kernel's ACPICA code more in line with the upstream.

Make the changes as per the above. While at it, make the relevant
function desctiption comments reflect the upstream ACPICA's ones.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Lv Zheng <lv.zheng@intel.com>

ACPI / sleep: Drop acpi_suspend() which is not used

The acpi_suspend() function has no callers, so drop it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>

ACPI: Drop power resources driver

The ACPI power resources driver is not very useful, because the only
thing it really does is to restore the state of the power resources
that were "on" before system suspend or hibernation, but that may be
achieved in a different way.

Drop the ACPI power resources driver entirely and add
acpi_resume_power_resources() that will walk the list of all
registered power resources during system resume and turn on the ones
that were "on" before the preceding system suspend or hibernation.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI: static sleep_states[] and acpi_gts_bfs_check

Only used in one file so should be static.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Len Brown <len.brown@intel.com>

ACPI / Wakeup: Simplify enabling of wakeup devices

To simplify the enabling of wakeup devices during system suspend and
hibernation, merge acpi_enable_wakeup_device_prep() with
acpi_disable_wakeup_device() and remove unnecessary (and no longer
valid) comments from the latter. Rename acpi_enable_wakeup_device()
to acpi_enable_wakeup_devices() and acpi_disable_wakeup_device()
to acpi_disable_wakeup_devices(), because these functions usually
operate on multiple device objects.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/acpi/sleep.h: Checkpatch cleanup

drivers/acpi/sleep.h:3: WARNING: space prohibited between function name and open parenthesis '('

Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Len Brown <len.brown@intel.com>

ACPI: convert acpi_device_lock spinlock to mutex

Convert acpi_device_lock to a mutex to avoid
a potential race upon access to /proc/acpi/wakeup

Delete the lock entirely in wakeup.c
since it is not necessary (and can not sleep)

Found-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

ACPICA: create acpica/ directory

also, delete sleep/ and delete ACPI_CFLAGS from Makefile

Signed-off-by: Len Brown <len.brown@intel.com>