linux-toradex.git/drivers/acpi/battery.c, branch v4.10

Replace with globally

2016-12-24T19:46:01+00:00

This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*'
  sed -i -e "s!$PATT!#include !" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro 
Signed-off-by: Linus Torvalds

ACPI / battery: If _BIX fails, retry with _BIF

2016-11-16T22:09:45+00:00

The Lenovo Yoga 300 laptop's firmware advertises that it provides the _BIX
the method to retrieve battery information. Unfortunately (some versions
of?) the implementation return with an error.

[   21.712228] ACPI Exception: AE_AML_PACKAGE_LIMIT, Index (0x000000010) is beyond end of object (length 0xD) (20160422/exoparg2-427)
[   21.712244] ACPI Error: Method parse/execution failed [\_SB.PCI0.LPCB.H_EC.BAT1._BIX] (Node ffff95f8ff0b20f0), AE_AML_PACKAGE_LIMIT (20160422/psparse-542)

The _BIF method does succeed and returns convincing data. We detect _BIX
failing and automatically retry with _BIF.

Signed-off-by: Dave Lambley 
Signed-off-by: Rafael J. Wysocki

ACPI / battery: Add sysfs representation after checking _BST

2016-08-30T22:35:16+00:00

Thus move sysfs_add_battery() after acpi_battery_get_state(), which doesn't
require the power_supply. Prevents possible hanged tasks if
acpi_battery_get_state() fails consistently (and takes a long time in doing
so) when called inside acpi_battery_add().

In this situation the battery module first calls sysfs_add_battery(),
which creates a power_supply, which spawns an async
power_supply_deferred_register_work() task, which shall try to hold the
parent battery device mutex (being already held) so this register work
is set up after device initialization. If initialization takes long enough
the thread will be eventually run and try to hold the mutex before
acpi_battery_add() had the chance to finish.

Eventually the 5 retries in acpi_battery_update_retry() fail, the error
state is propagated, and results in sysfs_remove_battery() being called
within the error handling paths of acpi_battery_add(), and the power_supply
tear down too.

This triggers a cancel_delayed_work_sync() of the deferred_register_work
task, which ends up in schedule(). The end result is that the deferred
task is blocked trying to acquire the parent device mutex, which is not
released because the thread doing initialization (and failure handling)
went to sleep awaiting for the deferred task to be cancelled.

The hanged tasks look like this:

INFO: task kworker/u8:0:6 blocked for more than 120 seconds.
 ...
Call Trace:
 [] schedule+0x35/0x80
 [] schedule_timeout+0x1ec/0x250
 [] ? check_preempt_curr+0x52/0x90
 [] ? ttwu_do_wakeup+0x19/0xe0
 [] wait_for_common+0xc5/0x190
 [] ? wake_up_q+0x70/0x70
 [] wait_for_completion+0x1d/0x20
 [] flush_work+0x111/0x1c0
 [] ? flush_workqueue_prep_pwqs+0x1a0/0x1a0
 [] __cancel_work_timer+0x9f/0x1d0
 [] cancel_delayed_work_sync+0x13/0x20
 [] power_supply_unregister+0x37/0xc0
 [] sysfs_remove_battery+0x3d/0x52 [battery]
 [] acpi_battery_add+0x112/0x181 [battery]
 [] acpi_device_probe+0x54/0x19b
 [] driver_probe_device+0x22c/0x440
 [] __driver_attach+0xd1/0xf0
 [] ? driver_probe_device+0x440/0x440
 [] bus_for_each_dev+0x6c/0xc0
 [] driver_attach+0x1e/0x20
 [] bus_add_driver+0x1c3/0x280
 [] driver_register+0x60/0xe0
 [] acpi_bus_register_driver+0x3b/0x43
 [] acpi_battery_init_async+0x1c/0x1e [battery]
 [] async_run_entry_fn+0x48/0x150
 [] process_one_work+0x1e9/0x440
 [] worker_thread+0x4b/0x4f0
 [] ? process_one_work+0x440/0x440
 [] kthread+0xd8/0xf0
 [] ret_from_fork+0x1f/0x40
 [] ? kthread_worker_fn+0x180/0x180

INFO: task kworker/u8:4:282 blocked for more than 120 seconds.
 ...
Call Trace:
 [] ? put_prev_entity+0x35/0x8b0
 [] schedule+0x35/0x80
 [] schedule_preempt_disabled+0xe/0x10
 [] __mutex_lock_slowpath+0xb3/0x120
 [] mutex_lock+0x1f/0x30
 [] power_supply_deferred_register_work+0x2b/0x50
 [] process_one_work+0x1e9/0x440
 [] worker_thread+0x4b/0x4f0
 [] ? process_one_work+0x440/0x440
 [] ? process_one_work+0x440/0x440
 [] kthread+0xd8/0xf0
 [] ret_from_fork+0x1f/0x40
 [] ? kthread_worker_fn+0x180/0x180

Making sysfs_add_battery() the last operation here means that the
power_supply won't be created yet when the acpi_add_battery() failure
handling happens, the deferred task won't even spawn, and
sysfs_remove_battery will just skip over the NULL battery->bat.

Signed-off-by: Carlos Garnacho 
Signed-off-by: Rafael J. Wysocki

ACPI / battery: Correctly serialise with the pending async probe

2016-05-20T23:25:07+00:00

async_synchronize_cookie() only serialises all tasks up to the specified
cookie, and importantly does not wait for the task corresponding with
the cookie. [This is so that it can be trivially used from inside the
async_func_t in order to serialise with all preceding tasks.] In order
to serialise with acpi_battery_init_async() we need to compensate and
pass in the next cookie instead.

The impact today is zero since performing an async_schedule() from inside
a module init function will trigger an async_synchronize_full() prior to
the module loader's completion. However, if the probe was moved to its
own unregistered async_domain, then the async_synchronize_cookie would
be replaced with an async_synchronize_full_domain.

Signed-off-by: Chris Wilson 
Signed-off-by: Rafael J. Wysocki

ACPI: Remove FSF mailing addresses

2015-07-08T00:27:32+00:00

There is no need to carry potentially outdated Free Software Foundation
mailing address in file headers since the COPYING file includes it.

Signed-off-by: Jarkko Nikula 
Signed-off-by: Rafael J. Wysocki

ACPI / battery: mark DMI table as __initconst

2015-06-15T12:23:44+00:00

The bat_dmi_table[] DMI table is referenced from the __init function
acpi_battery_init_async() only. It and its referenced functions can
therefore be marked __initconst to free up ~1kB of runtime memory after
initialization is done.

Signed-off-by: Mathias Krause 
Signed-off-by: Rafael J. Wysocki

ACPI / battery: minor tweaks to acpi_battery_units()

2015-06-15T12:23:06+00:00

Make the acpi_battery_units() function take a const argument and return
a const char*, too. Also make it static. It probably doesn't matter, as
gcc will be clever enough to optimize and inline the code even without
these hints. However, we also get rid of a #ifdef block by moving the
function closer to its usage location, so it's at least a small gain in
code readability.

Signed-off-by: Mathias Krause 
Signed-off-by: Rafael J. Wysocki

ACPI / battery: constify the offset tables

2015-06-15T12:21:22+00:00

The offset tables are only read, not modified. Make them const.

Signed-off-by: Mathias Krause 
Signed-off-by: Rafael J. Wysocki

ACPI / battery: ensure acpi_battery_init() has finish

2015-05-13T22:58:40+00:00

Make sure that async function scheduled with async_schedule() has already
been executed.

Signed-off-by: Luis Henriques 
Signed-off-by: Rafael J. Wysocki

ACPI / battery: drop useless return statements

2015-05-13T22:58:40+00:00

Signed-off-by: Luis Henriques 
Signed-off-by: Rafael J. Wysocki