Commit a22b41a31e ("sbs-battery: Probe should try talking to the
device") introduced a step in probing the SBS battery, that tries to
talk to the device before actually registering it, saying:
this driver doesn't actually try talking to the device at probe
time, so if it's incorrectly configured in the device tree or
platform data (or if the battery has been removed from the system),
then probe will succeed and every access will sit there and time
out. The end result is a possibly laggy system that thinks it has a
battery but can never read status, which isn't very useful.
Which is of course reasonable. However, it is also very well possible
for a device to boot up on wall-power and be connected to a battery
later on. This is a scenario that the driver supported before said patch
was applied, and even easily achieved by booting up with the battery
attached and removing it later on. sbs-battery's 'present' sysfs file
can be used to determine if the device is available or not.
So with automated device detection lacking for now, in some cases it is
possible that one wants to register a battery, even if none are attached
at the moment. To facilitate this, add a module parameter that can be
used to configure forced loading module loading time. If set, the battery
will always be registered without checking the sanity of the connection.
Signed-off-by: Frans Klaver <frans.klaver@xsens.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Change the ownership of power_supply structure from each driver
implementing the class to the power supply core.
The patch changes power_supply_register() function thus all drivers
implementing power supply class are adjusted.
Each driver provides the implementation of power supply. However it
should not be the owner of power supply class instance because it is
exposed by core to other subsystems with power_supply_get_by_name().
These other subsystems have no knowledge when the driver will unregister
the power supply. This leads to several issues when driver is unbound -
mostly because user of power supply accesses freed memory.
Instead let the core own the instance of struct 'power_supply'. Other
users of this power supply will still access valid memory because it
will be freed when device reference count reaches 0. Currently this
means "it will leak" but power_supply_put() call in next patches will
solve it.
This solves invalid memory references in following race condition
scenario:
Thread 1: charger manager
Thread 2: power supply driver, used by charger manager
THREAD 1 (charger manager) THREAD 2 (power supply driver)
========================== ==============================
psy = power_supply_get_by_name()
Driver unbind, .remove
power_supply_unregister()
Device fully removed
psy->get_property()
The 'get_property' call is executed in invalid context because the driver was
unbound and struct 'power_supply' memory was freed.
This could be observed easily with charger manager driver (here compiled
with max17040 fuel gauge):
$ cat /sys/devices/virtual/power_supply/cm-battery/capacity &
$ echo "1-0036" > /sys/bus/i2c/drivers/max17040/unbind
[ 55.725123] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[ 55.732584] pgd = d98d4000
[ 55.734060] [00000000] *pgd=5afa2831, *pte=00000000, *ppte=00000000
[ 55.740318] Internal error: Oops: 80000007 [#1] PREEMPT SMP ARM
[ 55.746210] Modules linked in:
[ 55.749259] CPU: 1 PID: 2936 Comm: cat Tainted: G W 3.19.0-rc1-next-20141226-00048-gf79f475f3c44-dirty #1496
[ 55.760190] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[ 55.766270] task: d9b76f00 ti: daf54000 task.ti: daf54000
[ 55.771647] PC is at 0x0
[ 55.774182] LR is at charger_get_property+0x2f4/0x36c
[ 55.779201] pc : [<00000000>] lr : [<c034b0b4>] psr: 60000013
[ 55.779201] sp : daf55e90 ip : 00000003 fp : 00000000
[ 55.790657] r10: 00000000 r9 : c06e2878 r8 : d9b26c68
[ 55.795865] r7 : dad81610 r6 : daec7410 r5 : daf55ebc r4 : 00000000
[ 55.802367] r3 : 00000000 r2 : daf55ebc r1 : 0000002a r0 : d9b26c68
[ 55.808879] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user
[ 55.815994] Control: 10c5387d Table: 598d406a DAC: 00000015
[ 55.821723] Process cat (pid: 2936, stack limit = 0xdaf54210)
[ 55.827451] Stack: (0xdaf55e90 to 0xdaf56000)
[ 55.831795] 5e80: 60000013 c01459c4 0000002a c06f8ef8
[ 55.839956] 5ea0: db651000 c06f8ef8 daebac00 c04cb668 daebac08 c0346864 00000000 c01459c4
[ 55.848115] 5ec0: d99eaa80 c06f8ef8 00000fff 00001000 db651000 c027f25c c027f240 d99eaa80
[ 55.856274] 5ee0: d9a06c00 c0146218 daf55f18 00001000 d99eaa80 db4c18c0 00000001 00000001
[ 55.864468] 5f00: daf55f80 c0144c78 c0144c54 c0107f90 00015000 d99eaab0 00000000 00000000
[ 55.872603] 5f20: 000051c7 00000000 db4c18c0 c04a9370 00015000 00001000 daf55f80 00001000
[ 55.880763] 5f40: daf54000 00015000 00000000 c00e53dc db4c18c0 c00e548c 0000000d 00008124
[ 55.888937] 5f60: 00000001 00000000 00000000 db4c18c0 db4c18c0 00001000 00015000 c00e5550
[ 55.897099] 5f80: 00000000 00000000 00001000 00001000 00015000 00000003 00000003 c000f364
[ 55.905239] 5fa0: 00000000 c000f1a0 00001000 00015000 00000003 00015000 00001000 0001333c
[ 55.913399] 5fc0: 00001000 00015000 00000003 00000003 00000002 00000000 00000000 00000000
[ 55.921560] 5fe0: 7fffe000 be999850 0000a225 b6f3c19c 60000010 00000003 00000000 00000000
[ 55.929744] [<c034b0b4>] (charger_get_property) from [<c0346864>] (power_supply_show_property+0x48/0x20c)
[ 55.939286] [<c0346864>] (power_supply_show_property) from [<c027f25c>] (dev_attr_show+0x1c/0x48)
[ 55.948130] [<c027f25c>] (dev_attr_show) from [<c0146218>] (sysfs_kf_seq_show+0x84/0x104)
[ 55.956298] [<c0146218>] (sysfs_kf_seq_show) from [<c0144c78>] (kernfs_seq_show+0x24/0x28)
[ 55.964536] [<c0144c78>] (kernfs_seq_show) from [<c0107f90>] (seq_read+0x1b0/0x484)
[ 55.972172] [<c0107f90>] (seq_read) from [<c00e53dc>] (__vfs_read+0x18/0x4c)
[ 55.979188] [<c00e53dc>] (__vfs_read) from [<c00e548c>] (vfs_read+0x7c/0x100)
[ 55.986304] [<c00e548c>] (vfs_read) from [<c00e5550>] (SyS_read+0x40/0x8c)
[ 55.993164] [<c00e5550>] (SyS_read) from [<c000f1a0>] (ret_fast_syscall+0x0/0x48)
[ 56.000626] Code: bad PC value
[ 56.011652] ---[ end trace 7b64343fbdae8ef1 ]---
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
[for the nvec part]
Reviewed-by: Marc Dietrich <marvin24@gmx.de>
[for compal-laptop.c]
Acked-by: Darren Hart <dvhart@linux.intel.com>
[for the mfd part]
Acked-by: Lee Jones <lee.jones@linaro.org>
[for the hid part]
Acked-by: Jiri Kosina <jkosina@suse.cz>
[for the acpi part]
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Add new structure 'power_supply_config' for holding run-time
initialization data like of_node, supplies and private driver data.
The power_supply_register() function is changed so all power supply
drivers need updating.
When registering the power supply this new 'power_supply_config' should be
used instead of directly initializing 'struct power_supply'. This allows
changing the ownership of power_supply structure from driver to the
power supply core in next patches.
When a driver does not use of_node or supplies then it should use NULL
as config. If driver uses of_node or supplies then it should allocate
config on stack and initialize it with proper values.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
[for the nvec part]
Reviewed-by: Marc Dietrich <marvin24@gmx.de>
[for drivers/platform/x86/compal-laptop.c]
Reviewed-by: Darren Hart <dvhart@linux.intel.com>
[for drivers/hid/*]
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
sbs-battery has a max design voltage but not a min design voltage field.
The SBS spec only has one design voltage:
http://www.sbs-forum.org/specs/sbdat110.pdf
Currently this is being used for max design voltage. This patch uses it
for min design voltage as well.
Signed-off-by: Simon Que <sque@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Todd Broch <tbroch@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
This CL supports two power_supply_property items for smart battery:
POWER_SUPPLY_PROP_MANUFACTURER and POWER_SUPPLY_PROP_MODEL_NAME such
that battery information 'manufacturer' and 'model_name' can be exported
to sysfs.
Signed-off-by: Cheng-Yi Chiang <cychiang@chromium.org>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
By passing in the dt node of this device, we enable the logic for linking
power_supplies together from dt. This is specified by adding a
"power-supplies" property with a phandle to the charger for a given
supply.
Enable this logic now for the sbs-battery driver.
Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>
Use dev_pm_ops instead of the deprecated legacy suspend/resume callbacks.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>
This eliminates having an #ifdef returning NULL for the case when OF is
disabled.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>
CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Anton Vorontsov <cbou@mail.ru>
Cc: David Woodhouse <dwmw2@infradead.org>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Anton Vorontsov <cbou@mail.ru>
Cc: David Woodhouse <dwmw2@infradead.org>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Anton Vorontsov <cbou@mail.ru>
Cc: David Woodhouse <dwmw2@infradead.org>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Turns out this driver doesn't actually try talking to the device at
probe time, so if it's incorrectly configured in the device tree or
platform data (or if the battery has been removed from the system),
then probe will succeed and every access will sit there and time out.
The end result is a possibly laggy system that thinks it has a battery
but can never read status, which isn't very useful.
Instead, just read any register (I chose status) at probe, and if that
fails, don't register the device.
Signed-off-by: Olof Johansson <olof@lixom.net>
Acked-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
power_supply_changed() events are triggerd based on the return value
of a get_property() call. However the property TECHNOLOGY is
hard-coded to LION in this driver, thus always succeeds.
So, with the battery removed, this triggers a false battery present
uevent. This uevent triggers a new query via power_supply_uevent()
which again starts to query all known properties and thus leads to
an infinite loop of battery present/not-present uevents.
This patch skips the battery presence detection for the hard-coded
property TECHNOLOGY.
Signed-off-by: Nikolaus Voss <n.voss@weinmann.de>
Acked-by Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Currently, the capacity exported by this driver refers to reg 0x0e,
which is the absolute state of charge which according to SBS
refers to the design capacity/ energy of the battery. It can be
> 100 % and drops below 100 % for a fully charged battery with
the battery aging.
This is not what the user exspects of a remaining capacity
indication between 0 and 100 % with 100 % referring to
a fully charged battery. This is provided by SBS reg 0x0d,
which is the relative state of charge referring to the
full charge capacity.
Signed-off-by: Nikolaus Voss <n.voss@weinmann.de>
Acked-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Factor out some boilerplate code for i2c driver registration
into module_i2c_driver.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Woogyom Kim <milo.kim@ti.com>
Cc: Daniel Jeong <daniel.jeong@ti.com>
Cc: Minkyu Kang <mk7.kang@samsung.com>
Cc: Peter Edwards <sweetlilmre@gmail.com>
Acked-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Acked-by: Rhyland Klein <rklein@nvidia.com>
Acked-by: Ryan Mallon <rmallon@gmail.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
It should be an of module table, not i2c.
Signed-off-by: Olof Johansson <olof@lixom.net>
Acked-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
The power supply name used to be fixed as "battery". This change allows
for multiple batteries by generating the name rather than using a fixed
value.
Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Now that this driver is named more generally, this change updates
the internal variables, defines and functions to use this new name.
Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
This driver for the bq20z75 implemented the register spec defined
by the SBS standard. As this is not unique to this the TI part this
was originally written for, we can generalize this driver to
show its support for any SBS compliant battery.
Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
