The of_node_put() function tests whether its argument is NULL and then
returns immediately. Thus the test around the calls is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Acked-by: NPali Rohár <pali.rohar@gmail.com>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

Commit b68c3161 (bq2415x_charger: Allow to load and use driver even if
notify device is not registered yet) introduced null pointer dereference in
case bq is NULL. This patch fixes it.

Fixes: b68c3161 ("bq2415x_charger: Allow to load and use driver even if notify device is not registered yet")
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NPali Rohár <pali.rohar@gmail.com>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

Driver bq2415x_charger works also without notify power supply device for
charger detection. But when charger detection is specified in DT, then
bq2415x_charger refused to loaded with -EPROBE_DEFER.

This patch rewrites code so that notify device for charger detection is
checked when power supply event is received and not when registering power
supply device. So this patch allows to use bq2415x_charger driver also when
kernel is compiled without driver for notify power supply device.

Now after this patch scheduled workqueue is called after INIT_DELAYED_WORK,
so it also fix problem when scheduled workqueue was called before init.
Signed-off-by: NPali Rohár <pali.rohar@gmail.com>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

Replace of_property_read_u32() with device_property_read_u32(), which is a
wrapper over ACPI and device tree enumeration methods.
When ACPI enumeration is used, automode is not supported. Therefore,
bq2415x_charger does not update its input current automatically, depending
on the USB port type that is connected to. Input current may be updated via
sysfs.
Signed-off-by: NAnda-Maria Nicolae <anda-maria.nicolae@intel.com>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

This patch fixes the following issues reported by checkpatch.pl:
- use -EINVAL instead of -ENOSYS, to fix warning message:
  "ENOSYS means 'invalid syscall nr' and nothing else"
- remove unnecessary log message
- split lines whose length is greater than 80 characters
- if an arm statement uses braces, add braces to the other arms of the
  respective statement, too
- match alignment with open parenthesis
Signed-off-by: NAnda-Maria Nicolae <anda-maria.nicolae@intel.com>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

Use power_supply_put() to decrement the power supply's device reference
counter (increased by power_supply_get_by_name() or
power_supply_get_by_phandle()).
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: NPavel Machek <pavel@ucw.cz>
Reviewed-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Reviewed-by: NSebastian Reichel <sre@kernel.org>
Signed-off-by: NSebastian 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: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

[for the nvec part]
Reviewed-by: NMarc Dietrich <marvin24@gmx.de>

[for compal-laptop.c]
Acked-by: NDarren Hart <dvhart@linux.intel.com>

[for the mfd part]
Acked-by: NLee Jones <lee.jones@linaro.org>

[for the hid part]
Acked-by: NJiri Kosina <jkosina@suse.cz>

[for the acpi part]
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

Replace direct calls to power supply function attributes with wrappers.
Wrappers provide safe access in case of unregistering the power
supply (e.g. by removing the driver). Replace:
 - get_property -> power_supply_get_property
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: NJonghwa Lee <jonghwa3.lee@samsung.com>
Acked-by: NPavel Machek <pavel@ucw.cz>
Reviewed-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Reviewed-by: NSebastian Reichel <sre@kernel.org>
Signed-off-by: NSebastian 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: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: NPavel Machek <pavel@ucw.cz>

[for the nvec part]
Reviewed-by: NMarc Dietrich <marvin24@gmx.de>

[for drivers/platform/x86/compal-laptop.c]
Reviewed-by: NDarren Hart <dvhart@linux.intel.com>

[for drivers/hid/*]
Reviewed-by: NJiri Kosina <jkosina@suse.cz>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

This patch adds bq24157s charger in the list of supported chargers.
bq24157s is similar to bq24158, except for Bit6 from Special Charger
Voltage/Enable Pin Status register, but this register is currently
not used by bq2415x_charger.
Signed-off-by: NAnda-Maria Nicolae <anda-maria.nicolae@intel.com>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

Fix coding style to comply with checkpatch.pl
Signed-off-by: NAnda-Maria Nicolae <anda-maria.nicolae@intel.com>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

Cleanup comments  for bq2415x_charger, bq27x00_battery.c.
Signed-off-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

Memory allocated for 'name' was leaking if required binding properties
were not present.

The memory for 'name' was allocated early at probe with kasprintf(). It
was freed in error paths executed before and after parsing DTS but not
in that error path.

Fix the error path for parsing device tree properties.
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Fixes: faffd234 ("bq2415x_charger: Add DT support")
Cc: <stable@vger.kernel.org>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

The power_supply_get_by_phandle() on error returns ENODEV or NULL.
The driver later expects obtained pointer to power supply to be
valid or NULL. If it is not NULL then it dereferences it in
bq2415x_notifier_call() which would lead to dereferencing ENODEV-value
pointer.

Properly handle the power_supply_get_by_phandle() error case by
replacing error value with NULL. This indicates that usb charger
detection won't be used.

Fix also memory leak of 'name' if power_supply_get_by_phandle() fails
with NULL and probe should defer.
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Fixes: faffd234 ("bq2415x_charger: Add DT support")
Cc: <stable@vger.kernel.org>
[small fix regarding the missing ti,usb-charger-detection info message]
Signed-off-by: NSebastian Reichel <sre@kernel.org>

Move sysfs_notify and i2c_transfer calls from bq2415x_notifier_call
to bq2415x_timer_work to avoid sleeping in atomic context.

This fixes the following bug:

[ 7.667449] Workqueue: events power_supply_changed_work
[ 7.673034] [<c0015c28>] (unwind_backtrace+0x0/0xe0) from [<c0011e1c>] (show_stack+0x10/0x14)
[ 7.682098] [<c0011e1c>] (show_stack+0x10/0x14) from [<c052cdd0>] (dump_stack+0x78/0xac)
[ 7.690704] [<c052cdd0>] (dump_stack+0x78/0xac) from [<c052a044>] (__schedule_bug+0x48/0x60)
[ 7.699645] [<c052a044>] (__schedule_bug+0x48/0x60) from [<c053071c>] (__schedule+0x74/0x638)
[ 7.708618] [<c053071c>] (__schedule+0x74/0x638) from [<c05301fc>] (schedule_timeout+0x1dc/0x24c)
[ 7.718017] [<c05301fc>] (schedule_timeout+0x1dc/0x24c) from [<c05316ec>] (wait_for_common+0x138/0x17c)
[ 7.727966] [<c05316ec>] (wait_for_common+0x138/0x17c) from [<c0362a70>] (omap_i2c_xfer+0x340/0x4a0)
[ 7.737640] [<c0362a70>] (omap_i2c_xfer+0x340/0x4a0) from [<c035d928>] (__i2c_transfer+0x40/0x74)
[ 7.747039] [<c035d928>] (__i2c_transfer+0x40/0x74) from [<c035e22c>] (i2c_transfer+0x6c/0x90)
[ 7.756195] [<c035e22c>] (i2c_transfer+0x6c/0x90) from [<c037ad24>] (bq2415x_i2c_write+0x48/0x78)
[ 7.765563] [<c037ad24>] (bq2415x_i2c_write+0x48/0x78) from [<c037ae60>] (bq2415x_set_weak_battery_voltage+0x4c/0x50)
[ 7.776824] [<c037ae60>] (bq2415x_set_weak_battery_voltage+0x4c/0x50) from [<c037bce8>] (bq2415x_set_mode+0xdc/0x14c)
[ 7.788085] [<c037bce8>] (bq2415x_set_mode+0xdc/0x14c) from [<c037bfb8>] (bq2415x_notifier_call+0xa8/0xb4)
[ 7.798309] [<c037bfb8>] (bq2415x_notifier_call+0xa8/0xb4) from [<c005f228>] (notifier_call_chain+0x38/0x68)
[ 7.808715] [<c005f228>] (notifier_call_chain+0x38/0x68) from [<c005f284>] (__atomic_notifier_call_chain+0x2c/0x3c)
[ 7.819732] [<c005f284>] (__atomic_notifier_call_chain+0x2c/0x3c) from [<c005f2a8>] (atomic_notifier_call_chain+0x14/0x18)
[ 7.831420] [<c005f2a8>] (atomic_notifier_call_chain+0x14/0x18) from [<c0378078>] (power_supply_changed_work+0x6c/0xb8)
[ 7.842864] [<c0378078>] (power_supply_changed_work+0x6c/0xb8) from [<c00556c0>] (process_one_work+0x248/0x440)
[ 7.853546] [<c00556c0>] (process_one_work+0x248/0x440) from [<c0055d6c>] (worker_thread+0x208/0x350)
[ 7.863372] [<c0055d6c>] (worker_thread+0x208/0x350) from [<c005b0ac>] (kthread+0xc8/0xdc)
[ 7.872131] [<c005b0ac>] (kthread+0xc8/0xdc) from [<c000e138>] (ret_from_fork+0x14/0x3c)

Fixes: 32260308 ("bq2415x_charger: Use power_supply notifier for automode")
Cc: <stable@vger.kernel.org>
Signed-off-by: NSebastian Reichel <sre@kernel.org>

This adds DT support to the bq2415x driver.
Signed-off-by: NSebastian Reichel <sre@debian.org>
Reviewed-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NAnton Vorontsov <anton@enomsg.org>

This patch removing set_mode_hook function from board data and replacing
it with new string variable of notifier power supply device. After this
change it is possible to add DT support because driver does not need
specific board function anymore. Only static data and name of power supply
device is required.
Signed-off-by: NPali Rohár <pali.rohar@gmail.com>
Reviewed-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NAnton Vorontsov <anton@enomsg.org>

As per the datasheets, maximum battery regulation voltage is 4440mV.

The formula is (voltage - offset) / step, so the maximum value is:
(4440 - 3500) / 20 = 47
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Thanks-to: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: NAnton Vorontsov <anton@enomsg.org>

Convert to the much saner new idr interface.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NAnton Vorontsov <cbou@mail.ru>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* Renamed mode BQ2415X_MODE_NONE to BQ2415X_MODE_OFF because this mode
  turning chaging completly off

* Added new mode BQ2415X_MODE_NONE which enable charging with maximal
  current limit 100mA (this is minimal safe value for bq2415x chips)
Signed-off-by: NPali Rohár <pali.rohar@gmail.com>
Signed-off-by: NAnton Vorontsov <anton@enomsg.org>

devm_kzalloc is device managed and makes error handling and code cleanup a
bit simpler.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NAnton Vorontsov <anton@enomsg.org>

module_i2c_driver() makes the code simpler by eliminating module_init and
module_exit calls.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NAnton Vorontsov <anton@enomsg.org>

<linux/version.h> is not required here.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NAnton Vorontsov <anton@enomsg.org>

I hate doing these style fixups myself, but I also hate inconsitent code.
Normally I just ask to resubmit the patch with the issues fixed, but N900
is special: I have a selfish interest in it. :)
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>

The bq2415x charger driver is needed for example on Nokia N900 for
charging battery. Driver is part of open source project to replace
proprietary battery management.
Signed-off-by: NPali Rohár <pali.rohar@gmail.com>
Signed-off-by: NAnton Vorontsov <anton.vorontsov@linaro.org>