Commit graph

428 commits

Author SHA1 Message Date
Rafael J. Wysocki
befd9b5b0c ACPI: EC: Relocate acpi_ec_create_query() and drop acpi_ec_delete_query()
Move acpi_ec_create_query() after acpi_ec_event_processor(), drop the
no longer needed forward declaration of the latter, and eliminate
acpi_ec_delete_query() which isn't really necessary.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-01 20:17:32 +01:00
Rafael J. Wysocki
c33676aa48 ACPI: EC: Make the event work state machine visible
The EC driver uses a relatively simple state machine for the event
work handling, but it is not really straightforward to figure out.

The states are as follows:

 "Ready": The event handling work can be submitted.

  In this state, the EC_FLAGS_QUERY_PENDING flag is clear.

 "In progress": The event handling work is pending or is being
                processed.  It cannot be submitted again.

  In ths state, the EC_FLAGS_QUERY_PENDING flag is set and both the
  events_to_process count is nonzero and the EC_FLAGS_QUERY_GUARDING
  flag is clear.

 "Complete": The event handling work has been completed, but it still
             cannot be submitted again.

  In ths state, the EC_FLAGS_QUERY_PENDING flag is set and the
  events_to_process count is zero or the EC_FLAGS_QUERY_GUARDING
  flag is set.

The state changes from "Ready" to "In progress" when new event is
detected by advance_transaction() and acpi_ec_submit_event() is
called by it.

Next, the state can change from "In progress" directly to "Ready" in
the following situations:

 * ec_event_clearing is ACPI_EC_EVT_TIMING_STATUS and the state of
   an ACPI_EC_COMMAND_QUERY transaction becomes ACPI_EC_COMMAND_POLL.

 * ec_event_clearing is ACPI_EC_EVT_TIMING_QUERY and the state of
   an ACPI_EC_COMMAND_QUERY transaction becomes
   ACPI_EC_COMMAND_COMPLETE.

 * ec_event_clearing is either ACPI_EC_EVT_TIMING_STATUS or
   ACPI_EC_EVT_TIMING_QUERY and there are no more events to
   process (ie. ec->events_to_process becomes 0).

If ec_event_clearing is ACPI_EC_EVT_TIMING_EVENT, however, the
state must change from "In progress" to "Complete" before it
can change to "Ready".  The changes from "In progress" to
"Complete" in that case occur in the following situations:

 * The state of an ACPI_EC_COMMAND_QUERY transaction becomes
   ACPI_EC_COMMAND_COMPLETE.

 * There are no more events to process (ie. ec->events_to_process
   becomes 0).

Finally, the state changes from "Complete" to "Ready" when
advance_transaction() is invoked when the state is "Complete" and
the state of the current transaction is not ACPI_EC_COMMAND_POLL.

To make this state machine visible in the code, add a new
event_state field to struct acpi_ec and modify the code to use
it istead the EC_FLAGS_QUERY_PENDING and EC_FLAGS_QUERY_GUARDING
flags.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-01 20:17:32 +01:00
Rafael J. Wysocki
c793570d87 ACPI: EC: Avoid queuing unnecessary work in acpi_ec_submit_event()
Notice that it is not necessary to queue up the event work again
if the while () loop in acpi_ec_event_handler() is still running
which is the case if nr_pending_queries is greater than 0 at the
beginning of acpi_ec_submit_event() and modify the code to avoid
doing that.

While at it, rename nr_pending_queries in struct acpi_ec to
events_to_process which actually matches the role of that field
and change its data type to unsigned int which is sufficient.

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-01 20:17:32 +01:00
Rafael J. Wysocki
eafe7509ab ACPI: EC: Rename three functions
Rename acpi_ec_submit_query() to acpi_ec_submit_event(),
acpi_ec_query() to acpi_ec_submit_query(), and
acpi_ec_complete_query() to acpi_ec_close_event() to make
the names reflect what the functions do.

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-01 20:17:32 +01:00
Rafael J. Wysocki
a105acd7e3 ACPI: EC: Simplify locking in acpi_ec_event_handler()
Because acpi_ec_event_handler() is a work function, it always
runs in process context with interrupts enabled, so it can use
spin_lock_irq() and spin_unlock_irq() for the locking.

Make it do so and adjust white space around those calls.

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-01 20:17:32 +01:00
Rafael J. Wysocki
388fb77dcf ACPI: EC: Rearrange the loop in acpi_ec_event_handler()
It is not necessary to check ec->nr_pending_queries against 0 in the
while () loop in acpi_ec_event_handler(), because that loop terminates
when ec->nr_pending_queries is 0 and the code depending on that can be
run after the loop has ended.

Modify the code accordingly and while at it rewrite the comment
regarding that code to make it clearer.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-01 20:17:32 +01:00
Rafael J. Wysocki
98d364509d ACPI: EC: Fold acpi_ec_check_event() into acpi_ec_event_handler()
Because acpi_ec_event_handler() is the only caller of
acpi_ec_check_event() and the separation of these two functions
makes it harder to follow the code flow, fold the latter into the
former (and simplify that code while at it).

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-01 20:17:32 +01:00
Rafael J. Wysocki
1f2350443d ACPI: EC: Pass one argument to acpi_ec_query()
Notice that the second argument to acpi_ec_query() is redundant,
because in the only case when it is not NULL, the value passed
through it is only checked against 0 and it can only be 0 when
acpi_ec_query() returns an error code, but its return value
is checked along with the value passed through its second
argument.

Accordingly, modify acpi_ec_query() to take only one argument
and while at it, change its handling of the case when
acpi_ec_transaction() returns an error so as to return that
error value to the caller right away.

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-01 20:17:32 +01:00
Rafael J. Wysocki
ca8283dcd9 ACPI: EC: Call advance_transaction() from acpi_ec_dispatch_gpe()
Calling acpi_dispatch_gpe() from acpi_ec_dispatch_gpe() is generally
problematic, because it may cause the spurious interrupt handling in
advance_transaction() to trigger in theory.

However, instead of calling acpi_dispatch_gpe() to dispatch the EC
GPE, acpi_ec_dispatch_gpe() can call advance_transaction() directly
on first_ec and it can pass 'false' as its second argument to indicate
calling it from process context.

Moreover, if advance_transaction() is modified to return a bool value
indicating whether or not the EC work needs to be flushed, it can be
used to avoid unnecessary EC work flushing in acpi_ec_dispatch_gpe(),
so change the code accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-01 20:17:32 +01:00
Rafael J. Wysocki
4a9af6cac0 ACPI: EC: Rework flushing of EC work while suspended to idle
The flushing of pending work in the EC driver uses drain_workqueue()
to flush the event handling work that can requeue itself via
advance_transaction(), but this is problematic, because that
work may also be requeued from the query workqueue.

Namely, if an EC transaction is carried out during the execution of
a query handler, it involves calling advance_transaction() which
may queue up the event handling work again.  This causes the kernel
to complain about attempts to add a work item to the EC event
workqueue while it is being drained and worst-case it may cause a
valid event to be skipped.

To avoid this problem, introduce two new counters, events_in_progress
and queries_in_progress, incremented when a work item is queued on
the event workqueue or the query workqueue, respectively, and
decremented at the end of the corresponding work function, and make
acpi_ec_dispatch_gpe() the workqueues in a loop until the both of
these counters are zero (or system wakeup is pending) instead of
calling acpi_ec_flush_work().

At the same time, change __acpi_ec_flush_work() to call
flush_workqueue() instead of drain_workqueue() to flush the event
workqueue.

While at it, use the observation that the work item queued in
acpi_ec_query() cannot be pending at that time, because it is used
only once, to simplify the code in there.

Additionally, clean up a comment in acpi_ec_query() and adjust white
space in acpi_ec_event_processor().

Fixes: f0ac20c3f6 ("ACPI: EC: Fix flushing of pending work")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-01 20:17:32 +01:00
wangzhitong
69cace6e18 ACPI: EC: Remove initialization of static variables to false
Remove the initialization of two static variables to false which is
pointless.

Signed-off-by: wangzhitong <wangzhitong@uniontech.com>
[ rjw: Subject and changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-11-03 19:17:40 +01:00
Binbin Zhou
eb794e3c6b ACPI: EC: Use ec_no_wakeup on HP ZHAN 66 Pro
EC interrupts constantly wake up system from s2idle, so set
ec_no_wakeup by default to keep the system in s2idle and reduce
energy consumption.

Signed-off-by: Binbin Zhou <zhoubinbin@uniontech.com>
[ rjw: Changelog and subject edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-11-03 19:13:01 +01:00
Rafael J. Wysocki
64f9111dd6 Merge branches 'acpi-ec', 'acpi-apei', 'acpi-soc' and 'acpi-misc'
* acpi-ec:
  ACPI: EC: trust DSDT GPE for certain HP laptop
  ACPI: EC: Make more Asus laptops use ECDT _GPE

* acpi-apei:
  ACPI: APEI: fix synchronous external aborts in user-mode
  ACPI: APEI: Don't warn if ACPI is disabled

* acpi-soc:
  ACPI: LPSS: Use kstrtol() instead of simple_strtol()

* acpi-misc:
  ACPI: NVS: fix doc warnings in nvs.c
  ACPI: NUMA: fix typo in a comment
  ACPI: OSL: Use DEFINE_RES_IO_NAMED() to simplify code
  ACPI: bus: Call kobject_put() in acpi_init() error path
  ACPI: bus: Remove unneeded assignment
  ACPI: configfs: Replace ACPI_INFO() with pr_debug()
  ACPI: ipmi: Remove address space handler in error path
  ACPI: event: Remove redundant initialization of local variable
  ACPI: sbshc: Fix fall-through warning for Clang
2021-06-29 15:51:25 +02:00
Zhang Rui
4370cbf350 ACPI: EC: trust DSDT GPE for certain HP laptop
On HP Pavilion Gaming Laptop 15-cx0xxx, the ECDT EC and DSDT EC share
the same port addresses but different GPEs. And the DSDT GPE is the
right one to use.

The current code duplicates DSDT EC with ECDT EC if the port addresses
are the same, and uses ECDT GPE as a result, which breaks this machine.

Introduce a new quirk for the HP laptop to trust the DSDT GPE,
and avoid duplicating even if the port addresses are the same.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=209989
Reported-and-tested-by: Shao Fu, Chen <leo881003@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-21 18:48:22 +02:00
Daniel Scally
a9e10e5873 ACPI: scan: Extend acpi_walk_dep_device_list()
The acpi_walk_dep_device_list() function is not as generic as its
name implies, serving only to decrement the dependency count for each
dependent device of the input.

Extend it to accept a callback which can be applied to all the
dependencies in acpi_dep_list.

Replace all existing calls to the function with calls to a wrapper,
passing a callback that applies the same dependency reduction.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Maximilian Luz <luzmaximilian@gmail.com>  # for platform/surface parts
Signed-off-by: Daniel Scally <djrscally@gmail.com>
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-07 16:45:05 +02:00
Chris Chiu
6306f04319 ACPI: EC: Make more Asus laptops use ECDT _GPE
More ASUS laptops have the _GPE define in the DSDT table with a
different value than the _GPE number in the ECDT.

This is causing media keys not working on ASUS X505BA/BP, X542BA/BP

Add model info to the quirks list.

Signed-off-by: Chris Chiu <chris.chiu@canonical.com>
Signed-off-by: Jian-Hong Pan <jhp@endlessos.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-05-21 19:17:20 +02:00
Rafael J. Wysocki
2a39a30f0d ACPI: EC: Clean up status flags checks in advance_transaction()
Eliminate comparisons from the status flags checks in
advance_transaction() (especially from the one that is only correct,
because the value of the flag checked in there is 1) and rearrange
the code for more clarity while at it.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-23 20:01:01 +01:00
Rafael J. Wysocki
631734fce3 ACPI: EC: Untangle error handling in advance_transaction()
Introduce acpi_ec_spurious_interrupt() for recording spurious
interrupts and use it for error handling in advance_transaction(),
drop the (now redundant) original error handling block from there
along with a frew goto statements that are not necessary any more.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-23 20:00:42 +01:00
Rafael J. Wysocki
902675fa87 ACPI: EC: Simplify error handling in advance_transaction()
Notice that the value of t in advance_transaction() does not change
after its initialization and:

 - Initialize t upfront (and rearrange the definitions of local
   variables while at it).

 - Check it against NULL in a block executed when it is NULL.

 - Skip error handling for t == NULL, because a valid pointer value
   of t is required for the error handling.

 - Drop the (now redundant) check of t against NULL from the error
   handling block and reduce the indentation level in there.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-23 20:00:34 +01:00
Rafael J. Wysocki
d2a2e6cceb ACPI: EC: Rename acpi_ec_is_gpe_raised()
Rename acpi_ec_is_gpe_raised() into acpi_ec_gpe_status_set(),
update its callers accordingly and drop the ternary operator
(which isn't really necessary in there) from it.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-23 20:00:25 +01:00
Rafael J. Wysocki
d269fb0313 ACPI: EC: Fold acpi_ec_clear_gpe() into its caller
Fold acpi_ec_clear_gpe() which is only used in one place into its
caller and clean up comments related to that function while at it.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-23 20:00:18 +01:00
Sebastian Andrzej Siewior
2e84ea5a32 ACPI: EC: Eliminate in_interrupt() usage
advance_transaction() is using in_interrupt() to distinguish between
an invocation from the interrupt handler and an invocation from
another part of the stack.

This looks misleading because chains like

  acpi_update_all_gpes() -> acpi_ev_gpe_detect() ->
  acpi_ev_detect_gpe() -> acpi_ec_gpe_handler()

should probably also behave as if they were called from an interrupt
handler.

Replace in_interrupt() usage with a function parameter.

Set this parameter to `true' if invoked from an interrupt handler
(acpi_ec_gpe_handler() and acpi_ec_irq_handler()) and `false'
otherwise.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
[ rjw: Subject edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-23 13:39:45 +01:00
Rafael J. Wysocki
e0e9ce390d ACPI: EC: PM: Drop ec_no_wakeup check from acpi_ec_dispatch_gpe()
It turns out that in some cases there are EC events to flush in
acpi_ec_dispatch_gpe() even though the ec_no_wakeup kernel parameter
is set and the EC GPE is disabled while sleeping, so drop the
ec_no_wakeup check that prevents those events from being processed
from acpi_ec_dispatch_gpe().

Reported-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-06 12:31:31 +02:00
Rafael J. Wysocki
5e92442bb4 ACPI: EC: PM: Flush EC work unconditionally after wakeup
Commit 607b9df630 ("ACPI: EC: PM: Avoid flushing EC work when EC
GPE is inactive") has been reported to cause some power button wakeup
events to be missed on some systems, so modify acpi_ec_dispatch_gpe()
to call acpi_ec_flush_work() unconditionally to effectively reverse
the changes made by that commit.

Also note that the problem which prompted commit 607b9df630 is not
reproducible any more on the affected machine.

Fixes: 607b9df630 ("ACPI: EC: PM: Avoid flushing EC work when EC GPE is inactive")
Reported-by: Raymond Tan <raymond.tan@intel.com>
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-06 12:31:31 +02:00
Xiongfeng Wang
fc293b7a0e ACPI: EC: add newline when printing 'ec_event_clearing' module parameter
When I cat acpi module parameter
'/sys/module/acpi/parameters/ec_event_clearing', it displays as follows.
It is better to add a newline for easy reading.

[root@hulk-202 ~]# cat /sys/module/acpi/parameters/ec_event_clearing
query[root@hulk-202 ~]#

Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-06-22 17:17:18 +02:00
Linus Torvalds
118d6e9829 ACPI updates for 5.8-rc1
- Update the ACPICA code in the kernel to upstream revision
    20200430:
 
    * Move acpi_gbl_next_cmd_num definition (Erik Kaneda).
 
    * Ignore AE_ALREADY_EXISTS status in the disassembler when parsing
      create operators (Erik Kaneda).
 
    * Add status checks to the dispatcher (Erik Kaneda).
 
    * Fix required parameters for _NIG and _NIH (Erik Kaneda).
 
    * Make acpi_protocol_lengths static (Yue Haibing).
 
  - Fix ACPI table reference counting errors in several places, mostly
    in error code paths (Hanjun Guo).
 
  - Extend the Generic Event Device (GED) driver to support _Exx and
    _Lxx handler methods (Ard Biesheuvel).
 
  - Add new acpi_evaluate_reg() helper and modify the ACPI PCI hotplug
    code to use it (Hans de Goede).
 
  - Add new DPTF battery participant driver and make the DPFT power
    participant driver create more sysfs device attributes (Srinivas
    Pandruvada).
 
  - Improve the handling of memory failures in APEI (James Morse).
 
  - Add new blacklist entry for Acer TravelMate 5735Z to the backlight
    driver (Paul Menzel).
 
  - Add i2c address for thermal control to the PMIC driver (Mauro
    Carvalho Chehab).
 
  - Allow the ACPI processor idle driver to work on platforms with
    only one ACPI C-state present (Zhang Rui).
 
  - Fix kobject reference count leaks in error code paths in two
    places (Qiushi Wu).
 
  - Delete unused proc filename macros and make some symbols static
    (Pascal Terjan, Zheng Zengkai, Zou Wei).
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Merge tag 'acpi-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:
 "These update the ACPICA code in the kernel to upstream revision
  20200430, fix several reference counting errors related to ACPI
  tables, add _Exx / _Lxx support to the GED driver, add a new
  acpi_evaluate_reg() helper, add new DPTF battery participant driver
  and extend the DPFT power participant driver, improve the handling of
  memory failures in the APEI code, add a blacklist entry to the
  backlight driver, update the PMIC driver and the processor idle
  driver, fix two kobject reference count leaks, and make a few janitory
  changes.

  Specifics:

   - Update the ACPICA code in the kernel to upstream revision 20200430:

      - Move acpi_gbl_next_cmd_num definition (Erik Kaneda).

      - Ignore AE_ALREADY_EXISTS status in the disassembler when parsing
        create operators (Erik Kaneda).

      - Add status checks to the dispatcher (Erik Kaneda).

      - Fix required parameters for _NIG and _NIH (Erik Kaneda).

      - Make acpi_protocol_lengths static (Yue Haibing).

   - Fix ACPI table reference counting errors in several places, mostly
     in error code paths (Hanjun Guo).

   - Extend the Generic Event Device (GED) driver to support _Exx and
     _Lxx handler methods (Ard Biesheuvel).

   - Add new acpi_evaluate_reg() helper and modify the ACPI PCI hotplug
     code to use it (Hans de Goede).

   - Add new DPTF battery participant driver and make the DPFT power
     participant driver create more sysfs device attributes (Srinivas
     Pandruvada).

   - Improve the handling of memory failures in APEI (James Morse).

   - Add new blacklist entry for Acer TravelMate 5735Z to the backlight
     driver (Paul Menzel).

   - Add i2c address for thermal control to the PMIC driver (Mauro
     Carvalho Chehab).

   - Allow the ACPI processor idle driver to work on platforms with only
     one ACPI C-state present (Zhang Rui).

   - Fix kobject reference count leaks in error code paths in two places
     (Qiushi Wu).

   - Delete unused proc filename macros and make some symbols static
     (Pascal Terjan, Zheng Zengkai, Zou Wei)"

* tag 'acpi-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (32 commits)
  ACPI: CPPC: Fix reference count leak in acpi_cppc_processor_probe()
  ACPI: sysfs: Fix reference count leak in acpi_sysfs_add_hotplug_profile()
  ACPI: GED: use correct trigger type field in _Exx / _Lxx handling
  ACPI: DPTF: Add battery participant driver
  ACPI: DPTF: Additional sysfs attributes for power participant driver
  ACPI: video: Use native backlight on Acer TravelMate 5735Z
  arm64: acpi: Make apei_claim_sea() synchronise with APEI's irq work
  ACPI: APEI: Kick the memory_failure() queue for synchronous errors
  mm/memory-failure: Add memory_failure_queue_kick()
  ACPI / PMIC: Add i2c address for thermal control
  ACPI: GED: add support for _Exx / _Lxx handler methods
  ACPI: Delete unused proc filename macros
  ACPI: hotplug: PCI: Use the new acpi_evaluate_reg() helper
  ACPI: utils: Add acpi_evaluate_reg() helper
  ACPI: debug: Make two functions static
  ACPI: sleep: Put the FACS table after using it
  ACPI: scan: Put SPCR and STAO table after using it
  ACPI: EC: Put the ACPI table after using it
  ACPI: APEI: Put the HEST table for error path
  ACPI: APEI: Put the error record serialization table for error path
  ...
2020-06-02 13:25:52 -07:00
Rafael J. Wysocki
228b79aa33 Merge branches 'acpi-processor', 'acpi-cppc', 'acpi-dbg', 'acpi-misc' and 'acpi-pci'
* acpi-processor:
  ACPI: processor: idle: Allow probing on platforms with one ACPI C-state

* acpi-cppc:
  ACPI: CPPC: Fix reference count leak in acpi_cppc_processor_probe()
  ACPI: CPPC: Make some symbols static

* acpi-dbg:
  ACPI: debug: Make two functions static

* acpi-misc:
  ACPI: GED: use correct trigger type field in _Exx / _Lxx handling
  ACPI: GED: add support for _Exx / _Lxx handler methods
  ACPI: Delete unused proc filename macros

* acpi-pci:
  ACPI: hotplug: PCI: Use the new acpi_evaluate_reg() helper
  ACPI: utils: Add acpi_evaluate_reg() helper
2020-06-01 17:19:06 +02:00
Rafael J. Wysocki
48c604151a Merge branches 'acpica' and 'acpi-tables'
* acpica:
  ACPICA: Update version to 20200430
  ACPICA: Fix required parameters for _NIG and _NIH
  ACPICA: Dispatcher: add status checks
  ACPICA: Disassembler: ignore AE_ALREADY_EXISTS status when parsing create operators
  ACPICA: Move acpi_gbl_next_cmd_num definition to acglobal.h
  ACPICA: Make acpi_protocol_lengths static

* acpi-tables:
  ACPI: sleep: Put the FACS table after using it
  ACPI: scan: Put SPCR and STAO table after using it
  ACPI: EC: Put the ACPI table after using it
  ACPI: APEI: Put the HEST table for error path
  ACPI: APEI: Put the error record serialization table for error path
  ACPI: APEI: Put the error injection table for error path and module exit
  ACPI: APEI: Put the boot error record table after parsing
  ACPI: watchdog: Put the watchdog action table after parsing
  ACPI: LPIT: Put the low power idle table after using it
2020-06-01 15:22:05 +02:00
Rafael J. Wysocki
5fcd735901 ACPI: EC: PM: s2idle: Extend GPE dispatching debug message
Add the "ACPI" string to the "EC GPE dispatched" message as it is
ACPI-related.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-05-25 12:10:41 +02:00
Rafael J. Wysocki
607b9df630 ACPI: EC: PM: Avoid flushing EC work when EC GPE is inactive
Flushing the EC work while suspended to idle when the EC GPE status
is not set causes some EC wakeup events (notably power button and
lid ones) to be missed after a series of spurious wakeups on the Dell
XPS13 9360 in my office.

If that happens, the machine cannot be woken up from suspend-to-idle
by the power button or lid status change and it needs to be woken up
in some other way (eg. by a key press).

Flushing the EC work only after successful dispatching the EC GPE,
which means that its status has been set, avoids the issue, so change
the code in question accordingly.

Fixes: 7b301750f7 ("ACPI: EC: PM: Avoid premature returns from acpi_s2idle_wake()")
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Chris Chiu <chiu@endlessm.com>
2020-05-18 13:15:13 +02:00
Pascal Terjan
a10660f778 ACPI: Delete unused proc filename macros
Those were used to create files in /proc/acpi long ago
and were missed when that code was deleted.

Signed-off-by: Pascal Terjan <pterjan@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-05-14 13:49:33 +02:00
Rafael J. Wysocki
7b301750f7 ACPI: EC: PM: Avoid premature returns from acpi_s2idle_wake()
If the EC GPE status is not set after checking all of the other GPEs,
acpi_s2idle_wake() returns 'false', to indicate that the SCI event
that has just triggered is not a system wakeup one, but it does that
without canceling the pending wakeup and re-arming the SCI for system
wakeup which is a mistake, because it may cause s2idle_loop() to busy
spin until the next valid wakeup event.  [If that happens, the first
spurious wakeup is still pending after acpi_s2idle_wake() has
returned, so s2idle_enter() does nothing, acpi_s2idle_wake()
is called again and it sees that the SCI has triggered, but no GPEs
are active, so 'false' is returned again, and so on.]

Fix that by moving all of the GPE checking logic from
acpi_s2idle_wake() to acpi_ec_dispatch_gpe() and making the
latter return 'true' only if a non-EC GPE has triggered and
'false' otherwise, which will cause acpi_s2idle_wake() to
cancel the pending SCI wakeup and re-arm the SCI for system
wakeup regardless of the EC GPE status.

This also addresses a lockup observed on an Elitegroup EF20EA laptop
after attempting to wake it up from suspend-to-idle by a key press.

Fixes: d5406284ff ("ACPI: PM: s2idle: Refine active GPEs check")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=207603
Reported-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Fixes: fdde0ff859 ("ACPI: PM: s2idle: Prevent spurious SCIs from waking up the system")
Link: https://lore.kernel.org/linux-acpi/CAB4CAwdqo7=MvyG_PE+PGVfeA17AHF5i5JucgaKqqMX6mjArbQ@mail.gmail.com/
Reported-by: Chris Chiu <chiu@endlessm.com>
Tested-by: Chris Chiu <chiu@endlessm.com>
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-05-11 10:11:38 +02:00
Hanjun Guo
f900bf4951 ACPI: EC: Put the ACPI table after using it
The embedded controller boot resources table needs to be
released after using it.

Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
[ rjw: avoid adding a label in acpi_ec_ecdt_start() ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-05-09 11:29:17 +02:00
Rafael J. Wysocki
d7e0481c0d ACPI: EC: Fix up fast path check in acpi_ec_add()
The fast path check in acpi_ec_add() is not incorrect, because in
fact acpi_device_hid(device) can be equal to ACPI_ECDT_HID only if
boot_ec is not NULL, but it may confuse static checkers, so change
it to explicitly check boot_ec upfront and use the slow path if
that pointer is NULL.

Link: https://lore.kernel.org/linux-acpi/20200406144217.GA68494@mwanda/
Fixes: 3d9b8dd832 ("ACPI: EC: Use fast path in acpi_ec_add() for DSDT boot EC")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-06 17:40:27 +02:00
Linus Torvalds
6d90508121 ACPI updates for 5.7-rc1
- Update the ACPICA code in the kernel to the 20200214 upstream
    release including:
 
    * Fix to re-enable the sleep button after wakeup (Anchal Agarwal).
    * Fixes for mistakes in comments and typos (Bob Moore).
    * ASL-ASL+ converter updates (Erik Kaneda).
    * Type casting cleanups (Sven Barth).
 
  - Clean up the intialization of the EC driver and eliminate some
    dead code from it (Rafael Wysocki).
 
  - Clean up the quirk tables in the AC and battery drivers (Hans de
    Goede).
 
  - Fix the global lock handling on x86 to ignore unspecified bit
    positions in the global lock field (Jan Engelhardt).
 
  - Add a new "tiny" driver for ACPI button devices exposed by VMs to
    guest kernels to send signals directly to init (Josh Triplett).
 
  - Add a kernel parameter to disable ACPI BGRT on x86 (Alex Hung).
 
  - Make the ACPI PCI host bridge and fan drivers use scnprintf() to
    avoid potential buffer overflows (Takashi Iwai).
 
  - Clean up assorted pieces of code:
 
    * Reorder "asmlinkage" to make g++ happy (Alexey Dobriyan).
    * Drop unneeded variable initialization (Colin Ian King).
    * Add missing __acquires/__releases annotations (Jules Irenge).
    * Replace list_for_each_safe() with list_for_each_entry_safe()
      (chenqiwu).
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Merge tag 'acpi-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:

   - Update the ACPICA code in the kernel to the 20200214 upstream
     release including:

       * Fix to re-enable the sleep button after wakeup (Anchal
         Agarwal).

       * Fixes for mistakes in comments and typos (Bob Moore).

       * ASL-ASL+ converter updates (Erik Kaneda).

       * Type casting cleanups (Sven Barth).

   - Clean up the intialization of the EC driver and eliminate some dead
     code from it (Rafael Wysocki).

   - Clean up the quirk tables in the AC and battery drivers (Hans de
     Goede).

   - Fix the global lock handling on x86 to ignore unspecified bit
     positions in the global lock field (Jan Engelhardt).

   - Add a new "tiny" driver for ACPI button devices exposed by VMs to
     guest kernels to send signals directly to init (Josh Triplett).

   - Add a kernel parameter to disable ACPI BGRT on x86 (Alex Hung).

   - Make the ACPI PCI host bridge and fan drivers use scnprintf() to
     avoid potential buffer overflows (Takashi Iwai).

   - Clean up assorted pieces of code:

       * Reorder "asmlinkage" to make g++ happy (Alexey Dobriyan).

       * Drop unneeded variable initialization (Colin Ian King).

       * Add missing __acquires/__releases annotations (Jules Irenge).

       * Replace list_for_each_safe() with list_for_each_entry_safe()
         (chenqiwu)"

* tag 'acpi-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (31 commits)
  ACPICA: Update version to 20200214
  ACPI: PCI: Use scnprintf() for avoiding potential buffer overflow
  ACPI: fan: Use scnprintf() for avoiding potential buffer overflow
  ACPI: EC: Eliminate EC_FLAGS_QUERY_HANDSHAKE
  ACPI: EC: Do not clear boot_ec_is_ecdt in acpi_ec_add()
  ACPI: EC: Simplify acpi_ec_ecdt_start() and acpi_ec_init()
  ACPI: EC: Consolidate event handler installation code
  acpi/x86: ignore unspecified bit positions in the ACPI global lock field
  acpi/x86: add a kernel parameter to disable ACPI BGRT
  x86/acpi: make "asmlinkage" part first thing in the function definition
  ACPI: list_for_each_safe() -> list_for_each_entry_safe()
  ACPI: video: remove redundant assignments to variable result
  ACPI: OSL: Add missing __acquires/__releases annotations
  ACPI / battery: Cleanup Lenovo Ideapad Miix 320 DMI table entry
  ACPI / AC: Cleanup DMI quirk table
  ACPI: EC: Use fast path in acpi_ec_add() for DSDT boot EC
  ACPI: EC: Simplify acpi_ec_add()
  ACPI: EC: Drop AE_NOT_FOUND special case from ec_install_handlers()
  ACPI: EC: Avoid passing redundant argument to functions
  ACPI: EC: Avoid printing confusing messages in acpi_ec_setup()
  ...
2020-03-30 15:17:04 -07:00
Rafael J. Wysocki
d5406284ff ACPI: PM: s2idle: Refine active GPEs check
The check for any active GPEs added by commit fdde0ff859 ("ACPI:
PM: s2idle: Prevent spurious SCIs from waking up the system") turns
out to be insufficiently precise to prevent some systems from
resuming prematurely due to a spurious EC wakeup, so refine it
by first checking if any GPEs other than the EC GPE are active
and skipping all of the SCIs coming from the EC that do not produce
any genuine wakeup events after processing.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=206629
Fixes: fdde0ff859 ("ACPI: PM: s2idle: Prevent spurious SCIs from waking up the system")
Reported-by: Ondřej Caletka <ondrej@caletka.cz>
Tested-by: Ondřej Caletka <ondrej@caletka.cz>
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-25 12:57:27 +01:00
Rafael J. Wysocki
b1e14999a4 ACPI: EC: Eliminate EC_FLAGS_QUERY_HANDSHAKE
The EC_FLAGS_QUERY_HANDSHAKE switch is never set in the current
code (the only function setting it is defined under #if 0) and
has no effect whatever, so eliminate it and drop the code
depending on it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-14 11:04:17 +01:00
Rafael J. Wysocki
65a691f5f8 ACPI: EC: Do not clear boot_ec_is_ecdt in acpi_ec_add()
The reason for clearing boot_ec_is_ecdt in acpi_ec_add() (if a
PNP0C09 device object matching the ECDT boot EC had been found in
the namespace) was to cause acpi_ec_ecdt_start() to return early,
but since the latter does not look at boot_ec_is_ecdt any more,
acpi_ec_add() need not clear it.

Moreover, doing that may be confusing as it may cause "DSDT" to be
printed instead of "ECDT" in the EC initialization completion
message, so stop doing it.

While at it, split the EC initialization completion message into
two messages, one regarding the boot EC and another one printed
regardless of whether or not the EC at hand is the boot one.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-14 11:04:17 +01:00
Rafael J. Wysocki
98ada3c59d ACPI: EC: Simplify acpi_ec_ecdt_start() and acpi_ec_init()
Notice that the return value of acpi_ec_init() is discarded anyway,
so it can be void and it doesn't need to check the return values of
acpi_bus_register_driver() and acpi_ec_ecdt_start() called by it.
Thus the latter can be void too and it really has nothing to do
if acpi_ec_add() has already found an EC matching the boot one in the
namespace.  Also, acpi_ec_ecdt_get_handle() can be folded into it.

Modify the code accordingly and while at it create a propoer kerneldoc
comment to document acpi_ec_ecdt_start() and move the remark regarding
ASUS X550ZE along with the related bug URL from acpi_ec_init() into
that comment.

Additionally, fix up a stale comment in acpi_ec_init().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-14 11:04:17 +01:00
Rafael J. Wysocki
03e9a0e057 ACPI: EC: Consolidate event handler installation code
Commit 406857f773 ("ACPI: EC: add support for hardware-reduced
systems") made ec_install_handlers() return an error on failures
to configure a GPIO IRQ for the EC, but that is inconsistent with
the handling of the GPE event handler installation failures even
though it is exactly the same issue and the driver can respond to
it in the same way in both cases (the EC can be actively polled
for events through its registers if the event handler installation
fails).

Moreover, it requires acpi_ec_add() to take that special case into
account and disagrees with the ec_install_handlers() header comment.

For this reason, rework the event handler installation code in
ec_install_handlers() to explicitly take deferred probing (that
may be needed in the GPIO IRQ case) into account and to avoid
failing the EC initialization in any other case.

Among other things, reduce code duplication between
install_gpe_event_handler() and install_gpio_irq_event_handler() by
moving some code from there into ec_install_handlers() itself and
simplify the error code path in acpi_ec_add().

While at it, turn the ec_install_handlers() header comment into
a proper kerneldoc one and add some general control flow information
to it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Jian-Hong Pan <jian-hong@endlessm.com>
2020-03-14 10:59:44 +01:00
Rafael J. Wysocki
3d9b8dd832 ACPI: EC: Use fast path in acpi_ec_add() for DSDT boot EC
If the boot EC comes from the DSDT, its ACPI handle is equal to the
handle of a device object with the PNP0C09 device ID.  If that
device object is passed to acpi_ec_add(), it is not necessary to
allocate a new EC structure for it and parse it, because that has
been done already, so change the function to use the fast path in
that case.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-02 11:25:21 +01:00
Rafael J. Wysocki
e3cfabcd73 ACPI: EC: Simplify acpi_ec_add()
First, notice that if the device ID in acpi_ec_add() is equal to
ACPI_ECDT_HID, boot_ec_is_ecdt must be set, because this means
that the device object passed to acpi_ec_add() comes from
acpi_ec_ecdt_start() which fails if boot_ec_is_ecdt is unset.
Accordingly, boot_ec_is_ecdt need not be set again in that case,
so drop that redundant update of it from the code.

Next, ec->handle must be a valid ACPI handle right before
returning 0 from acpi_ec_add(), because it either is the handle
of the device object passed to that function, or it is the boot EC
handle coming from acpi_ec_ecdt_start() which fails if it cannot
find a valid handle for the boot EC.  Moreover, the object with
that handle is regarded as a valid representation of the EC in all
cases, so there is no reason to avoid the _DEP list update walk if
that handle is the boot EC handle.  Accordingly, drop the dep_update
local variable from acpi_ec_add() and call acpi_walk_dep_device_list()
for ec->handle unconditionally before returning 0 from it.

Finally, the ec local variable in acpi_ec_add() need not be
initialized to NULL and the status local variable declaration
can be moved to the block in which it is used, so change the code
in accordance with these observations.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-02 11:25:13 +01:00
Rafael J. Wysocki
7247f0c24c ACPI: EC: Drop AE_NOT_FOUND special case from ec_install_handlers()
If the status value returned by acpi_install_address_space_handler()
in ec_install_handlers() is AE_NOT_FOUND, it is treated in a special
way, apparently because it might mean a _REG method evaluation
failure (at least that is the case according to the comment in
there), but acpi_install_address_space_handler() does not take
_REG evaluation errors into account at all, so the AE_NOT_FOUND
special handling is confusing at best.

For this reason, change ec_install_handlers() to stop the EC and
return -ENODEV on all acpi_install_address_space_handler() errors.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-02-27 22:56:28 +01:00
Rafael J. Wysocki
a2b691772a ACPI: EC: Avoid passing redundant argument to functions
After commit 406857f773 ("ACPI: EC: add support for hardware-reduced
systems") the handle_events argument passed to ec_install_handlers()
and acpi_ec_setup() is redundant, because it is always 'false' when
the device argument passed to them in NULL and it is always 'true'
otherwise, so the device argument can be tested against NULL instead
of testing the handle_events one.

Accordingly, modify ec_install_handlers() and acpi_ec_setup() to take
two arguments and reduce the number of checks in the former.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-02-27 22:55:22 +01:00
Rafael J. Wysocki
c823c17a8e ACPI: EC: Avoid printing confusing messages in acpi_ec_setup()
It doesn't really make sense to pass ec->handle of the ECDT EC to
acpi_handle_info(), because it is set to ACPI_ROOT_OBJECT in
acpi_ec_ecdt_probe(), so rework acpi_ec_setup() to avoid using
acpi_handle_info() for printing messages.

First, notice that the "Used as first EC" message is not really
useful, because it is immediately followed by a more meaningful one
from either acpi_ec_ecdt_probe() or acpi_ec_dsdt_probe() (the latter
also includes the EC object path), so drop it altogether.

Second, use pr_info() for printing the EC configuration information.

While at it, make the code in question avoid printing invalid GPE or
IRQ numbers and make it print the GPE/IRQ information only when the
driver is ready to handle events.

Fixes: 72c77b7ea9 ("ACPI / EC: Cleanup first_ec/boot_ec code")
Fixes: 406857f773 ("ACPI: EC: add support for hardware-reduced systems")
Cc: 5.5+ <stable@vger.kernel.org> # 5.5+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-02-27 22:51:36 +01:00
Rafael J. Wysocki
f0ac20c3f6 ACPI: EC: Fix flushing of pending work
Commit 016b87ca5c ("ACPI: EC: Rework flushing of pending work")
introduced a subtle bug into the flushing of pending EC work while
suspended to idle, which may cause the EC driver to fail to
re-enable the EC GPE after handling a non-wakeup event (like a
battery status change event, for example).

The problem is that the work item flushed by flush_scheduled_work()
in __acpi_ec_flush_work() may disable the EC GPE and schedule another
work item expected to re-enable it, but that new work item is not
flushed, so __acpi_ec_flush_work() returns with the EC GPE disabled
and the CPU running it goes into an idle state subsequently.  If all
of the other CPUs are in idle states at that point, the EC GPE won't
be re-enabled until at least one CPU is woken up by another interrupt
source, so system wakeup events that would normally come from the EC
then don't work.

This is reproducible on a Dell XPS13 9360 in my office which
sometimes stops reacting to power button and lid events (triggered
by the EC on that machine) after switching from AC power to battery
power or vice versa while suspended to idle (each of those switches
causes the EC GPE to trigger for several times in a row, but they
are not system wakeup events).

To avoid this problem, it is necessary to drain the workqueue
entirely in __acpi_ec_flush_work(), but that cannot be done with
respect to system_wq, because work items may be added to it from
other places while __acpi_ec_flush_work() is running.  For this
reason, make the EC driver use a dedicated workqueue for EC events
processing (let that workqueue be ordered so that EC events are
processed sequentially) and use drain_workqueue() on it in
__acpi_ec_flush_work().

Fixes: 016b87ca5c ("ACPI: EC: Rework flushing of pending work")
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-02-11 10:07:43 +01:00
Rafael J. Wysocki
3df663a147 ACPI: EC: Reference count query handlers under lock
There is a race condition in acpi_ec_get_query_handler()
theoretically allowing query handlers to go away before refernce
counting them.

In order to avoid it, call kref_get() on query handlers under
ec->mutex.

Also simplify the code a bit while at it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-12-27 11:04:21 +01:00
Rafael J. Wysocki
1e4230f56d Merge branches 'pm-sleep', 'pm-cpuidle', 'pm-cpufreq', 'pm-devfreq' and 'pm-avs'
* pm-sleep:
  ACPI: PM: s2idle: Rework ACPI events synchronization
  ACPI: EC: Rework flushing of pending work

* pm-cpuidle:
  cpuidle: minor Kconfig help text fixes
  cpuidle: Drop disabled field from struct cpuidle_state
  cpuidle: Fix Kconfig indentation

* pm-cpufreq:
  cpufreq: Fix Kconfig indentation

* pm-devfreq:
  PM / devfreq: Add missing locking while setting suspend_freq

* pm-avs:
  power: avs: Fix Kconfig indentation
2019-12-04 10:20:17 +01:00
Rafael J. Wysocki
016b87ca5c ACPI: EC: Rework flushing of pending work
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>
2019-12-02 09:22:54 +01:00
Daniel Drake
406857f773 ACPI: EC: add support for hardware-reduced systems
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>
2019-10-28 16:00:09 +01:00