There is a race condition in the ACPI EC driver, between
__acpi_ec_flush_event() and acpi_ec_event_handler(), that may
cause systems to stay in suspended-to-idle forever after a wakeup
event coming from the EC.
Namely, acpi_s2idle_wake() calls acpi_ec_flush_work() to wait until
the delayed work resulting from the handling of the EC GPE in
acpi_ec_dispatch_gpe() is processed, and that function invokes
__acpi_ec_flush_event() which uses wait_event() to wait for
ec->nr_pending_queries to become zero on ec->wait, and that wait
queue may be woken up too early.
Suppose that acpi_ec_dispatch_gpe() has caused acpi_ec_gpe_handler()
to run, so advance_transaction() has been called and it has invoked
acpi_ec_submit_query() to queue up an event work item, so
ec->nr_pending_queries has been incremented (under ec->lock). The
work function of that work item, acpi_ec_event_handler() runs later
and calls acpi_ec_query() to process the event. That function calls
acpi_ec_transaction() which invokes acpi_ec_transaction_unlocked()
and the latter wakes up ec->wait under ec->lock, but it drops that
lock before returning.
When acpi_ec_query() returns, acpi_ec_event_handler() acquires
ec->lock and decrements ec->nr_pending_queries, but at that point
__acpi_ec_flush_event() (woken up previously) may already have
acquired ec->lock, checked the value of ec->nr_pending_queries (and
it would not have been zero then) and decided to go back to sleep.
Next, if ec->nr_pending_queries is equal to zero now, the loop
in acpi_ec_event_handler() terminates, ec->lock is released and
acpi_ec_check_event() is called, but it does nothing unless
ec_event_clearing is equal to ACPI_EC_EVT_TIMING_EVENT (which is
not the case by default). In the end, if no more event work items
have been queued up while executing acpi_ec_transaction_unlocked(),
there is nothing to wake up __acpi_ec_flush_event() again and it
sleeps forever, so the suspend-to-idle loop cannot make progress and
the system is permanently suspended.
To avoid this issue, notice that it actually is not necessary to
wait for ec->nr_pending_queries to become zero in every case in
which __acpi_ec_flush_event() is used.
First, during platform-based system suspend (not suspend-to-idle),
__acpi_ec_flush_event() is called by acpi_ec_disable_event() after
clearing the EC_FLAGS_QUERY_ENABLED flag, which prevents
acpi_ec_submit_query() from submitting any new event work items,
so calling flush_scheduled_work() and flushing ec_query_wq
subsequently (in order to wait until all of the queries in that
queue have been processed) would be sufficient to flush all of
the pending EC work in that case.
Second, the purpose of the flushing of pending EC work while
suspended-to-idle described above really is to wait until the
first event work item coming from acpi_ec_dispatch_gpe() is
complete, because it should produce system wakeup events if
that is a valid EC-based system wakeup, so calling
flush_scheduled_work() followed by flushing ec_query_wq is also
sufficient for that purpose.
Rework the code to follow the above observations.
Fixes: 56b9918490 ("PM: sleep: Simplify suspend-to-idle control flow")
Reported-by: Kenneth R. Crudup <kenny@panix.com>
Tested-by: Kenneth R. Crudup <kenny@panix.com>
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
As defined in the ACPI spec section 12.11, ACPI hardware-reduced
platforms define the EC SCI interrupt as a GpioInt in the _CRS object.
This replaces the previous way of using a GPE for this interrupt;
GPE blocks are not available on reduced hardware platforms.
Add support for handling this interrupt as an EC event source, and
avoid GPE usage on reduced hardware platforms.
This enables the use of several media keys (e.g. screen brightness
up/down) on Asus UX434DA.
Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In preparation for supporting reduced hardware platforms which use a
GpioInt instead of a GPE, rename some functions and constants to have
more appropriate names. No logical changes.
Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 10a08fd65e ("ACPI: PM: Set up EC GPE for system wakeup from
drivers that need it") assumed that the EC GPE would only need to be
set up for system wakeup if either the intel-hid or the intel-vbtn
driver was in use, but that turns out to be incorrect. In particular,
on ASUS Zenbook UX430UNR/i7-8550U, if the EC GPE is not enabled while
suspended, the system cannot be woken up by opening the lid or
pressing a key, and that machine doesn't use any of the drivers
mentioned above.
For this reason, always set up the EC GPE for system wakeup from
suspend-to-idle by setting and clearing its wake mask in the ACPI
suspend-to-idle callbacks.
Fixes: 10a08fd65e ("ACPI: PM: Set up EC GPE for system wakeup from drivers that need it")
Reported-by: Kristian Klausen <kristian@klausen.dk>
Tested-by: Kristian Klausen <kristian@klausen.dk>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add a pm_pr_dbg() debug statement to acpi_ec_dispatch_gpe() to print
a message when the EC GPE has been dispatched (because its status
was set).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Move some routines, including acpi_ec_dispatch_gpe(), that are only
used if CONFIG_PM_SLEEP is set to the #ifdef block containing the EC
suspend and resume callbacks, to make the "full EC PM picture" easier
to follow.
While at it, move the header of acpi_ec_dispatch_gpe() in the
header file to a CONFIG_PM_SLEEP #ifdef block.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Change acpi_ec_suspend() to use pm_suspend_no_platform() instead of
acpi_sleep_no_ec_events(), which allows the latter to be eliminated
along with the s2idle_in_progress variable which is only used by it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Since the ACPI SCI is set up for system wakeup before the "noirq"
suspend of devices, it is better to make suspend-to-idle follow
suspend-to-RAM (S3) and switch over the EC to polling during "noirq"
suspend (and back to interrupt-based flow during "noirq" resume).
The frequency of spurious wakeup interrupts from the EC may be
reduced this way.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
The EC GPE needs to be set up for system wakeup only if there is a
driver depending on it, either intel-hid or intel-vbtn, bound to a
button device that is expected to wake up the system from sleep (such
as the power button on some Dell systems, like the XPS13 9360). It
doesn't need to be set up for waking up the system from sleep in any
other cases and whether or not it is expected to wake up the system
from sleep doesn't depend on whether or not the LPS0 device is
present in the ACPI namespace.
For this reason, rearrange the ACPI suspend-to-idle code to make the
drivers depending on the EC GPE wakeup take care of setting it up and
decouple that from the LPS0 device handling.
While at it, make intel-hid and intel-vbtn prepare for system wakeup
only if they are allowed to wake up the system from sleep by user
space (via sysfs).
[Note that acpi_ec_mark_gpe_for_wake() and acpi_ec_set_gpe_wake_mask()
are there to prevent the EC GPE from being disabled by the
acpi_enable_all_wakeup_gpes() call in acpi_s2idle_prepare(), so on
systems with either intel-hid or intel-vbtn this change doesn't
affect any interactions with the hardware or platform firmware.]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
On some systems, if suspend-to-idle is used, the EC may signal system
wakeup events (power button events, for example) as well as events
that should not cause the system to resume and acpi_ec_dispatch_gpe()
needs to be called to determine whether or not the system should
resume then. In particular, if acpi_ec_dispatch_gpe() doesn't detect
any EC events at all, the system should remain suspended, so it is
useful to know when that is the case.
For this reason, make acpi_ec_dispatch_gpe() return a bool value
indicating whether or not any EC events have been detected by it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Based on 3 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [kishon] [vijay] [abraham]
[i] [kishon]@[ti] [com] this program is distributed in the hope that
it will be useful but without any warranty without even the implied
warranty of merchantability or fitness for a particular purpose see
the gnu general public license for more details
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version [author] [graeme] [gregory]
[gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
[kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
[hk] [hemahk]@[ti] [com] this program is distributed in the hope
that it will be useful but without any warranty without even the
implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 1105 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On some Samsung hardware, it is necessary to clear events accumulated by
the EC during sleep. These ECs stop reporting GPEs until they are manually
polled, if too many events are accumulated.
Thus the CLEAR_ON_RESUME quirk is introduced to send EC query commands
unconditionally after resume to clear all the EC query events on those
platforms.
Later, commit 4c237371f2 ("ACPI / EC: Remove old CLEAR_ON_RESUME quirk")
removes the CLEAR_ON_RESUME quirk because we thought the new EC IRQ
polling logic should handle this case.
Now it has been proved that the EC IRQ Polling logic does not fix the
issue actually because we got regression report on these Samsung
platforms after removing the quirk.
Thus revert commit 4c237371f2 ("ACPI / EC: Remove old CLEAR_ON_RESUME
quirk") to introduce back the Samsung quirk in this patch.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=44161
Tested-by: Ortwin Glück <odi@odi.ch>
Tested-by: Francisco Cribari <cribari@gmail.com>
Tested-by: Balazs Varga <balazs4web@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Consolidate boot EC checks in acpi_ec_add(), put the acpi_is_boot_ec()
checks directly into it and drop the latter.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Notice that acpi_ec_add() calls acpi_config_boot_ec() when it finds
that the device object passed to it represents a "boot" EC, but in
that case the ec pointer passed to acpi_config_boot_ec() is guaranteed
to be equal to boot_ec and ec->handle is passed as the handle
argument to it, so acpi_config_boot_ec() really only calls
acpi_ec_setup() and prints a message.
Avoid the pointless checks in acpi_config_boot_ec() by calling
acpi_ec_setup() directly and print the message separately.
With the above changes in place, there are no users of
acpi_config_boot_ec(), so drop it.
No intentional functional impact except for a changed message.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since acpi_ec_dsdt_probe() returns early if boot_ec is set, it is
always unset when that function calls acpi_config_boot_ec() (passing
ec->handle as the handle argument to it). Thus it is not really
useful to call acpi_config_boot_ec() at that point. It is sufficient to
call acpi_ec_setup() directly and (if that is successful) set boot_ec,
so make acpi_ec_dsdt_probe() do that and avoid some pointless checks
in acpi_config_boot_ec().
No intentional functional impact except for a changed message.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since acpi_ec_ecdt_probe() is called when boot_ec is not set, it
doesn't neeed to take the other possibility into account.
Accordingly, it only needs to set the handle field in the ec object
to ACPI_ROOT_OBJECT, call acpi_ec_setup() and (if that is successful)
set boot_ec to ec and boot_ec_is_ecdt to 'true'. Make it do so
directly, without calling acpi_config_boot_ec(), and avoid some
pointless checks in the latter.
No intentional functional impact except for a changed message.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The boot_ec variable is not used outside of the file it is defined
in, so declare it as static.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Both acpi_ec_dsdt_probe() and acpi_ec_ecdt_probe() may be void as
their return values are ignored anyway. This allows a couple of
gotos and labels to go away from there.
Moreover, acpi_ec_ecdt_probe() only needs to allocate the ec
object after getting the ECDT pointer and checking it, so the
pointless memory allocation and release on systems without the
ECDT can be avoided by reordering it.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There are systems in which non-wakeup GPEs fire during the "noirq"
suspend stage of suspending devices and that effectively prevents the
system that tries to suspend to idle from entering any low-power
state at all. If the offending GPE fires regularly and often enough,
the system appears to be suspended, but in fact it is in a tight loop
over "noirq" suspend and "noirq" resume of devices all the time.
To prevent that from happening, disable all non-wakeup GPEs except
for the EC GPE for suspend-to-idle (the EC GPE is special, because
on some systems it has to be enabled for power button wakeup events
to be generated as expected).
Fixes: 147a7d9d25 (ACPI / PM: Do not reconfigure GPEs for suspend-to-idle)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201987
Reported-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 2c4d6baf1b (ACPI / EC: Use ec_no_wakeup on more Thinkpad X1
Carbon 6th systems) changed the DMI table to match all systems where
DMI product family is "Thinkpad X1 Carbon 6th". However, the system I
have here has this string written differently (ThinkPad vs. Thinkpad)
which makes the match fail.
In addition to that, after BIOS upgrade Robin now has the same string
than my system has (perhaps newer BIOS has changed the string).
In any case add another DMI entry to acpi_ec_no_wakeup[] table hopefully
covering all the X1 Carbon 6th systems out there.
Fixes: 2c4d6baf1b (ACPI / EC: Use ec_no_wakeup on more Thinkpad X1 Carbon 6th systems)
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[ rjw: Rebase and change the ident string to match the product familiy ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Like on X1C6, on X1Y3 EC interrupts constantly wake up system from
s2idle, the power consumption is extremely high.
So make ec_no_wakeup be true as default to keep system in s2idle mode
and reduce power consumption.
Power button works when ec_no_wakeup=true.
Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ec_no_wakeup matcher added for Thinkpad X1 Carbon 6th gen systems
beyond matched only a single DMI model (20KGS3JF01), that didn't cover
my laptop (20KH002JUS). Change to match based on DMI product family to
cover all X1 6th gen systems.
Signed-off-by: Robin H. Johnson <robbat2@gentoo.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On this system EC interrupt triggers constantly kicking devices out of
low power states and thus blocking power management. The system also has
a PCIe root port hosting Alpine Ridge Thunderbolt controller and it
never gets a chance to go to D3cold because of this.
Since the power button works the same regardless if EC interrupt is
enabled or not during s2idle, add a quirk for this machine that sets
ec_no_wakeup=true preventing spurious wakeups.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On platforms where the Low Power S0 Idle _DSM interface is used,
on wakeup from suspend-to-idle, when it is known that the ACPI SCI
has triggered while suspended, dispatch the EC GPE in order to catch
all EC events that may have triggered the wakeup before carrying out
the noirq phase of device resume.
That is needed to handle power button wakeup on some platforms where
the EC goes into a low-power mode during suspend-to-idle and while in
that mode it will discard events after a timeout. If that timeout is
shorter than the time it takes to complete the noirq resume of
devices, looking for EC events after the latter is too late.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reported-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wendy Wang <wendy.wang@intel.com>
Commit 662591461c (ACPI / EC: Drop EC noirq hooks to fix a
regression) modified the ACPI EC driver so that it doesn't switch
over to busy polling mode during noirq stages of system suspend and
resume in an attempt to fix an issue resulting from that behavior.
However, that modification introduced a system resume regression on
Thinkpad X240, so make the EC driver switch over to the polling mode
during noirq stages of system suspend and resume again, which
effectively reverts the problematic commit.
Fixes: 662591461c (ACPI / EC: Drop EC noirq hooks to fix a regression)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=197863
Reported-by: Markus Demleitner <m@tfiu.de>
Tested-by: Markus Demleitner <m@tfiu.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
acpi_ec.gpe is "unsigned long", hence treating it as "u32" would expose
the wrong half on big-endian 64-bit systems. Fix this by changing its
type to "u32" and removing the cast, as all other code already uses u32
or sometimes even only u8.
Fixes: 1195a09816 (ACPI: Provide /sys/kernel/debug/ec/...)
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On platforms (ASUS X550ZE and possibly all ASUS X series) with valid ECDT
EC but invalid DSDT EC, EC PM ops won't be invoked as ECDT EC is not an
ACPI device. Thus the following commit actually removed post-resume
acpi_ec_enable_event() invocation for such platforms, and triggered a
regression on them that after being resumed, EC (actually should be ECDT)
driver stops handling EC events:
Commit: c2b46d679b
Subject: ACPI / EC: Add PM operations to improve event handling for resume process
Notice that the root cause actually is "ECDT is not an ACPI device" rather
than "the timing of acpi_ec_enable_event() invocation", this patch fixes
this issue by enumerating ECDT EC as an ACPI device. Due to the existence
of the noirq stage, the ability of tuning the timing of
acpi_ec_enable_event() invocation is still meaningful.
This patch is a little bit different from the posted fix by moving
acpi_config_boot_ec() from acpi_ec_ecdt_start() to acpi_ec_add() to make
sure that EC event handling won't be stopped as long as the ACPI EC driver
is bound. Thus the following sequence shouldn't disable EC event handling:
unbind,suspend,resume,bind.
Fixes: c2b46d679b (ACPI / EC: Add PM operations to improve event handling for resume process)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=196847
Reported-by: Luya Tshimbalanga <luya@fedoraproject.org>
Tested-by: Luya Tshimbalanga <luya@fedoraproject.org>
Cc: 4.9+ <stable@vger.kernel.org> # 4.9+
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Summary of modules changes for the 4.15 merge window:
- Treewide module_param_call() cleanup, fix up set/get function
prototype mismatches, from Kees Cook
- Minor code cleanups
Signed-off-by: Jessica Yu <jeyu@kernel.org>
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Merge tag 'modules-for-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull module updates from Jessica Yu:
"Summary of modules changes for the 4.15 merge window:
- treewide module_param_call() cleanup, fix up set/get function
prototype mismatches, from Kees Cook
- minor code cleanups"
* tag 'modules-for-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module: Do not paper over type mismatches in module_param_call()
treewide: Fix function prototypes for module_param_call()
module: Prepare to convert all module_param_call() prototypes
kernel/module: Delete an error message for a failed memory allocation in add_module_usage()
Originally the Samsung quirks removed by commit 4c237371 can be covered
by commit e923e8e7 and ec_freeze_events=Y mode. But commit 9c40f956
changed ec_freeze_events=Y back to N, making this problem re-surface.
Actually, if commit e923e8e7 is robust enough, we can freely change
ec_freeze_events mode, so this patch fixes the issue by improving
commit e923e8e7.
Related commits listed in the merged order:
Commit: e923e8e79e
Subject: ACPI / EC: Fix an issue that SCI_EVT cannot be detected
after event is enabled
Commit: 4c237371f2
Subject: ACPI / EC: Remove old CLEAR_ON_RESUME quirk
Commit: 9c40f956ce
Subject: Revert "ACPI / EC: Enable event freeze mode..." to fix
a regression
This patch not only fixes the reported post-resume EC event triggering
source issue, but also fixes an unreported similar issue related to the
driver bind by adding EC event triggering source in ec_install_handlers().
Fixes: e923e8e79e (ACPI / EC: Fix an issue that SCI_EVT cannot be detected after event is enabled)
Fixes: 4c237371f2 (ACPI / EC: Remove old CLEAR_ON_RESUME quirk)
Fixes: 9c40f956ce (Revert "ACPI / EC: Enable event freeze mode..." to fix a regression)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=196833
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reported-by: Alistair Hamilton <ahpatent@gmail.com>
Tested-by: Alistair Hamilton <ahpatent@gmail.com>
Cc: 4.11+ <stable@vger.kernel.org> # 4.11+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Several function prototypes for the set/get functions defined by
module_param_call() have a slightly wrong argument types. This fixes
those in an effort to clean up the calls when running under type-enforced
compiler instrumentation for CFI. This is the result of running the
following semantic patch:
@match_module_param_call_function@
declarer name module_param_call;
identifier _name, _set_func, _get_func;
expression _arg, _mode;
@@
module_param_call(_name, _set_func, _get_func, _arg, _mode);
@fix_set_prototype
depends on match_module_param_call_function@
identifier match_module_param_call_function._set_func;
identifier _val, _param;
type _val_type, _param_type;
@@
int _set_func(
-_val_type _val
+const char * _val
,
-_param_type _param
+const struct kernel_param * _param
) { ... }
@fix_get_prototype
depends on match_module_param_call_function@
identifier match_module_param_call_function._get_func;
identifier _val, _param;
type _val_type, _param_type;
@@
int _get_func(
-_val_type _val
+char * _val
,
-_param_type _param
+const struct kernel_param * _param
) { ... }
Two additional by-hand changes are included for places where the above
Coccinelle script didn't notice them:
drivers/platform/x86/thinkpad_acpi.c
fs/lockd/svc.c
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
... and __initconst if applicable.
Based on similar work for an older kernel in the Grsecurity patch.
[JD: fix toshiba-wmi build]
[JD: add htcpen]
[JD: move __initconst where checkscript wants it]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
EC_FLAGS_COMMAND_STORM is actually used to mask GPE during IRQ processing.
This patch cleans it up using more readable flag/function names.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Tomislav Ivek <tomislav.ivek@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Use the observation that the EC command/data register addresses are
sufficient to determine if two EC devices are equivelent to modify
acpi_is_boot_ec().
Then, for the removed comparison factors, EC ID and EC GPE, they need
to be synchronized for the boot_ec:
1. Before registering the BIOS-provided EC event handlers in
acpi_ec_register_query_methods(), the namespace node holding
_Qxx methods should be located. The real namespace PNP0C09
device location then is apparently more trustworthy than the
ECDT EC ID.
2. Because of the ASUS quirks, the ECDT EC GPE is more trustworthy
than the namespace PNP0C09 device's _GPE setting.
Use the above observations to synchronize the boot_ec settings in
acpi_ec_add().
Finally, change the order of acpi_ec_ecdt_start() and acpi_ec_add(),
called from acpi_bus_register_driver(), so as to follow the fast path
of determining the location of _Qxx.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
[ rjw : Changelog & comments ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 2a5708409e (ACPI / EC: Fix a gap that ECDT EC cannot handle
EC events) introduced acpi_ec_ecdt_start(), but that function is
invoked before acpi_ec_query_init(), which is too early. This causes
the kernel to crash if an EC event occurs after boot, when ec_query_wq
is not valid:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000102
...
Workqueue: events acpi_ec_event_handler
task: ffff9f539790dac0 task.stack: ffffb437c0e10000
RIP: 0010:__queue_work+0x32/0x430
Normally, the DSDT EC should always be valid, so acpi_ec_ecdt_start()
is actually a no-op in the majority of cases. However, commit
c712bb58d8 (ACPI / EC: Add support to skip boot stage DSDT probe)
caused the probing of the DSDT EC as the "boot EC" to be skipped when
the ECDT EC is valid and uncovered the bug.
Fix this issue by invoking acpi_ec_ecdt_start() after acpi_ec_query_init()
in acpi_ec_init().
Link: https://jira01.devtools.intel.com/browse/LCK-4348
Fixes: 2a5708409e (ACPI / EC: Fix a gap that ECDT EC cannot handle EC events)
Fixes: c712bb58d8 (ACPI / EC: Add support to skip boot stage DSDT probe)
Reported-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: Feng Chenzhou <chenzhoux.feng@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit eed4d47efe (ACPI / sleep: Ignore spurious SCI wakeups from
suspend-to-idle) introduced acpi_freeze_sync() whose purpose is to
flush all of the processing of possible wakeup events signaled via
the ACPI SCI. However, it doesn't flush the query workqueue used
by the EC driver, so the events generated by the EC may not be
processed timely which leads to issues (increased overhead at least,
lost events possibly).
To fix that introduce acpi_ec_flush_work() that will flush all of
the outstanding EC work and call it from acpi_freeze_sync().
Fixes: eed4d47efe (ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
After commit 8110dd281e (ACPI / sleep: EC-based wakeup from
suspend-to-idle on recent systems) the configuration of GPEs,
including the EC one, is not changed during suspend-to-idle on
recent systems. That's in order to make system wakeup events
generated by the EC work, in particular.
However, on some of the systems in question (for example on Dell
XPS13 9365), in addition to generating system wakeup events the
EC generates a heartbeat sequence of interrupts that have nothing
to do with wakeup while suspended, and the Low Power Idle S0 _DSM
interface doesn't change that behavior.
The users of those systems may prefer to disable the EC GPE during
system suspend, for the cost of non-functional power button wakeup
or similar, but currently there is no way to do that.
For this reason, add a new module parameter, ec_no_wakeup, for the
EC driver module that, if set, will cause the EC GPE to be disabled
during system suspend and re-enabled during the subsequent system
resume.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=192591#c106
Amends: 8110dd281e (ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems)
Reported-and-tested-by: Patrik Kullman <patrik.kullman@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On Lenovo ThinkPad X1 Carbon - the 5th Generation, enabling an earlier
EC event freezing timing causes acpitz-virtual-0 to report a stuck
48C temparature. And with EC firmware revisioned as 1.14, without
reverting back to old EC event freezing timing, the fan still blows
up after a system resume.
This reverts the culprit change so that the regression can be fixed
without upgrading the EC firmware.
Fixes: d30283057e (ACPI / EC: Enable event freeze mode to improve event handling)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=191181#c168
Tested-by: Damjan Georgievski <gdamjan@gmail.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: 4.9+ <stable@vger.kernel.org> # 4.9+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
According to bug reports, although the busy polling mode can make
noirq stages execute faster, it causes abnormal fan blowing up after
system resume (see the first link below for a video demonstration)
on Lenovo ThinkPad X1 Carbon - the 5th Generation. The problem can
be fixed by upgrading the EC firmware on that machine.
However, many reporters confirm that the problem can be fixed by
stopping busy polling during suspend/resume and for some of them
upgrading the EC firmware is not an option.
For this reason, drop the noirq stage hooks from the EC driver
to fix the regression.
Fixes: c3a696b6e8 (ACPI / EC: Use busy polling mode when GPE is not enabled)
Link: https://youtu.be/9NQ9x-Jm99Q
Link: https://bugzilla.kernel.org/show_bug.cgi?id=196129
Reported-by: Andreas Lindhe <andreas@lindhe.io>
Tested-by: Gjorgji Jankovski <j.gjorgji@gmail.com>
Tested-by: Damjan Georgievski <gdamjan@gmail.com>
Tested-by: Fernando Chaves <nanochaves@gmail.com>
Tested-by: Tomislav Ivek <tomislav.ivek@gmail.com>
Tested-by: Denis P. <theoriginal.skullburner@gmail.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- Update the ACPICA code in the kernel to upstream revision
revision 20170531 (which covers all of the new material from
ACPI 6.2) including:
* Support for the PinFunction(), PinConfig(), PinGroup(),
PinGroupFunction(), and PinGroupConfig() resource descriptors
(Mika Westerberg).
* Support for new subtables in HEST and SRAT, new notify value
for HEST, header support for TPM2 table changes, and BGRT
Status field update (Bob Moore).
* Support for new PCCT subtables (David Box).
* Support for _LSI, _LSR, _LSW, and _HMA as predefined methods
(Erik Schmauss).
* Support for the new WSMT, HMAT, and PPTT tables (Lv Zheng).
* New UUID values for Processor Properties (Bob Moore).
* New notify values for memory attributes and graceful shutdown
(Bob Moore).
* Fix related to the PCAT_COMPAT MADT flag (Janosch Hildebrand).
* Resource to AML conversion fix for resources containing GPIOs
(Mika Westerberg).
* Disassembler-related updates (Bob Moore, David Box, Erik
Schmauss).
* Assorted fixes and cleanups (Bob Moore, Erik Schmauss, Lv Zheng,
Cao Jin).
- Modify ACPICA to always use designated initializers for function
pointer structures to make the structure layout randomization GCC
plugin work with it (Kees Cook).
- Update the tables configfs interface to unload SSDTs on configfs
entry removal (Jan Kiszka).
- Add support for the GPI1 regulator to the xpower PMIC Operation
Region handler (Hans de Goede).
- Fix ACPI EC issues related to conflicting EC definitions in the
ECDT and in the ACPI namespace (Lv Zheng, Carlo Caione, Chris
Chiu).
- Fix an interrupt storm issue in the EC driver and make its debug
output work with dynamic debug as expected (Lv Zheng).
- Add ACPI backlight quirk for Dell Precision 7510 (Shih-Yuan Lee).
- Fix whitespace in pr_fmt() to align log entries properly in some
places in the ACPI subsystem (Vincent Legoll).
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Merge tag 'acpi-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki:
"These mostly update the ACPICA code in the kernel to upstream revision
20170531 which covers all of the new material from ACPI 6.2, including
new tables (WSMT, HMAT, PPTT), new subtables and definition changes
for some existing tables (BGRT, HEST, SRAT, TPM2, PCCT), new resource
descriptor macros for pin control, support for new predefined methods
(_LSI, _LSR, _LSW, _HMA), fixes and cleanups.
On top of that, an additional ACPICA change from Kees (which also is
upstream already) switches all of the definitions of function pointer
structures in ACPICA to use designated initializers so as to make the
structure layout randomization GCC plugin work with it.
The rest is a few fixes and cleanups in the EC driver, an xpower PMIC
driver update, a new backlight blacklist entry, and update of the
tables configfs interface and a messages formatting cleanup.
Specifics:
- Update the ACPICA code in the kernel to upstream revision revision
20170531 (which covers all of the new material from ACPI 6.2)
including:
* Support for the PinFunction(), PinConfig(), PinGroup(),
PinGroupFunction(), and PinGroupConfig() resource descriptors
(Mika Westerberg).
* Support for new subtables in HEST and SRAT, new notify value for
HEST, header support for TPM2 table changes, and BGRT Status
field update (Bob Moore).
* Support for new PCCT subtables (David Box).
* Support for _LSI, _LSR, _LSW, and _HMA as predefined methods
(Erik Schmauss).
* Support for the new WSMT, HMAT, and PPTT tables (Lv Zheng).
* New UUID values for Processor Properties (Bob Moore).
* New notify values for memory attributes and graceful shutdown
(Bob Moore).
* Fix related to the PCAT_COMPAT MADT flag (Janosch Hildebrand).
* Resource to AML conversion fix for resources containing GPIOs
(Mika Westerberg).
* Disassembler-related updates (Bob Moore, David Box, Erik
Schmauss).
* Assorted fixes and cleanups (Bob Moore, Erik Schmauss, Lv Zheng,
Cao Jin).
- Modify ACPICA to always use designated initializers for function
pointer structures to make the structure layout randomization GCC
plugin work with it (Kees Cook).
- Update the tables configfs interface to unload SSDTs on configfs
entry removal (Jan Kiszka).
- Add support for the GPI1 regulator to the xpower PMIC Operation
Region handler (Hans de Goede).
- Fix ACPI EC issues related to conflicting EC definitions in the
ECDT and in the ACPI namespace (Lv Zheng, Carlo Caione, Chris
Chiu).
- Fix an interrupt storm issue in the EC driver and make its debug
output work with dynamic debug as expected (Lv Zheng).
- Add ACPI backlight quirk for Dell Precision 7510 (Shih-Yuan Lee).
- Fix whitespace in pr_fmt() to align log entries properly in some
places in the ACPI subsystem (Vincent Legoll)"
* tag 'acpi-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (63 commits)
ACPI / EC: Add quirk for GL720VMK
ACPI / EC: Fix media keys not working problem on some Asus laptops
ACPI / EC: Add support to skip boot stage DSDT probe
ACPI / EC: Enhance boot EC sanity check
ACPI / video: Add quirks for the Dell Precision 7510
ACPI: EC: Fix EC command visibility for dynamic debug
ACPI: EC: Fix an EC event IRQ storming issue
ACPICA: Use designated initializers
ACPICA: Update version to 20170531
ACPICA: Update a couple of debug output messages
ACPICA: acpiexec: enhance local signal handler
ACPICA: Simplify output for the ACPI Debug Object
ACPICA: Unix application OSL: Correctly handle control-c (EINTR)
ACPICA: Improvements for debug output only
ACPICA: Disassembler: allow conflicting external declarations to be emitted.
ACPICA: Disassembler: add external op to namespace on first pass
ACPICA: Disassembler: prevent external op's from opening a new scope
ACPICA: Changed Gbl_disasm_flag to acpi_gbl_disasm_flag
ACPICA: Changing External to a named object
ACPICA: Update two error messages to emit control method name
...
ASUS GL720VMK is also affected by the EC GPE preference issue.
Signed-off-by: Carlo Caione <carlo@caione.org>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Some Asus laptops (verified on X550VXK/FX502VD/FX502VE) get no
interrupts when pressing media keys thus the corresponding functions
are not invoked. It's due to the _GPE defines in DSDT for EC returns
differnt value compared to the GPE Number in ECDT. Confirmed with Asus
that the vale in ECDT is the correct one. This commit uses DMI quirks
to prevent calling _GPE when doing ec_parse_device() and keep the ECDT
GPE number setting for the EC device.
With previous commit, it is ensured that if there is an ECDT, it can
always be kept as boot_ec, this patch thus can implement a quirk on
top of the determined ECDT boot_ec.
Link: https://phabricator.endlessm.com/T16033
Link: https://phabricator.endlessm.com/T16722
Link: https://bugzilla.kernel.org/show_bug.cgi?id=195651
Tested-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Chris Chiu <chiu@endlessm.com>
Signed-off-by: Carlo Caione <carlo@caione.org>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We prepared _INI/_STA methods for \_SB, \_SB.PCI0, \_SB.LID0 and
\_SB.EC, _HID(PNP0C09)/_CRS/_GPE for \_SB.EC to poke Windows behavior
with qemu, we got the following execution sequence:
\_SB._INI
\_SB.PCI0._STA
\_SB.LID0._STA
\_SB.EC._STA
\_SB.PCI0._INI
\_SB.LID0._INI
\_SB.EC._INI
There is no extra DSDT EC device enumeration process occurring before
the main ACPI device enumeration process. That means acpi_ec_dsdt_probe()
is not Windows-compatible.
Tracking back, it was added by the following commit:
Commit: c5279dee26
Subject: ACPI: EC: Add some basic check for ECDT data
but that commit was misguided.
Why we shouldn't enumerate DSDT EC before the main ACPI device
enumeration?
The only way to know if the DSDT EC is valid would be to evaluate its
_STA control method, but it's not safe to evaluate this control method
that early and out of the ACPI enumeration process, because _STA may
refer to entities (such as resources or ACPI device objects) that may
not have been initialized before OSPM starts to enumerate them via
the main ACPI device enumeration.
But after we had reverted back to the expected behavior, a regression
was reported. On that platform, there is no ECDT, but the platform
control methods access EC operation region earlier than Linux expects
causing some ACPI method execution errors. For this reason, we just
go back to old behavior to still probe DSDT EC as the boot EC.
However, that turns out to lead to yet another functional breakage
and in order to work around all of the problems, we skip boot stage
DSDT probe when the ECDT exists so that a later quirk can always use
correct ECDT GPE setting.
Link: http://bugzilla.kernel.org/show_bug.cgi?id=11880
Link: http://bugzilla.kernel.org/show_bug.cgi?id=119261
Link: http://bugzilla.kernel.org/show_bug.cgi?id=195651
Tested-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
[ rjw: Changelog & comments massage ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
It's reported that some buggy BIOS tables can contain 2 DSDT ECs, one of
them is invalid but acpi_ec_dsdt_probe() fails to pick the valid one.
This patch simply enhances sanity checks in ec_parse_device() as a
workaround to skip probing wrong namespace ECs.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=195651
Tested-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
acpi_ec_cmd_string() currently is only enabled for "DEBUG" macro, but users
trend to use CONFIG_DYNAMIC_DEBUG and enable ec.c pr_debug() print-outs by
"dyndbg='file ec.c +p'". In this use case, all command names are turned
into UNDEF and the log is confusing. This affects bugzilla triage work.
This patch fixes this issue by enabling acpi_ec_cmd_string() for
CONFIG_DYNAMIC_DEBUG.
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: Feng Chenzhou <chenzhoux.feng@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The EC event IRQ (SCI_EVT) can only be handled by submitting QR_EC. As the
EC driver handles SCI_EVT in a workqueue, after SCI_EVT is flagged and
before QR_EC is submitted, there is a period risking IRQ storming. EC IRQ
must be masked for this period but linux EC driver never does so.
No end user notices the IRQ storming and no developer fixes this known
issue because:
1. The EC IRQ is always edge triggered GPE, and
2. The kernel can execute no-op EC IRQ handler very fast.
For edge-triggered EC GPE platforms, it is only reported of post-resume EC
event lost issues, there won't be an IRQ storming. For level triggered EC
GPE platforms, fortunately the kernel is always fast enough to execute such
a no-op EC IRQ handler so that the IRQ handler won't be accumulated to
starve the task contexts, causing a real IRQ storming.
But the IRQ storming actually can still happen when:
1. The EC IRQ performs like level triggered GPE, and
2. The kernel EC debugging log is turned on but the console is slow enough.
There are more and more platforms using EC GPE as wake GPE where the EC GPE
is likely designed as level triggered. Then when EC debugging log is
enabled, the EC IRQ handler is no longer a no-op but dumps IRQ status to
the consoles. If the consoles are slow enough, the EC IRQs can arrive much
faster than executing the handler. Finally the accumulated EC event IRQ
handlers starve the task contexts, causing the IRQ storming to occur, and
the kernel hangs can be observed during boot/resume.
This patch fixes this issue by masking EC IRQ for this period:
1. Begins when there is an SCI_EVT IRQ pending, and
2. Ends when there is a QR_EC completed (SCI_EVT acknowledged).
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: Feng Chenzhou <chenzhoux.feng@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rafael J. Wysocki
Daniel Drake
Thomas Gleixner
Zhang Rui
Mika Westerberg
Aaron Ma
Robin H. Johnson
Geert Uytterhoeven
Lv Zheng
Linus Torvalds
Kees Cook
Christoph Hellwig
Carlo Caione
Chris Chiu