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path: root/drivers/power/ds2781_battery.c
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2015-07-27power: ds2781_battery: clean up eeprom read/write functionsVladimir Zapolskiy
The change removes redundant calculation of left space on eeprom while reading or writing "param_eeprom" or "user_eeprom", the checks are not needed, since this task is done on caller side in fs/sysfs/file.c Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Sebastian Reichel <sre@kernel.org>
2015-03-13power_supply: Change ownership from driver to coreKrzysztof Kozlowski
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>
2015-03-13power_supply: Move run-time configuration to separate structureKrzysztof Kozlowski
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>
2012-11-28power: remove use of __devexitBill Pemberton
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>
2012-11-28power: remove use of __devinitBill Pemberton
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>
2012-11-28power: remove use of __devexit_pBill Pemberton
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>
2012-08-22ds2781_battery: Replace call to kzalloc with devm_kzallocDevendra Naga
With devm_kzalloc there is no need of freeing at the errorpath and also at unregister it. Signed-off-by: Devendra Naga <develkernel412222@gmail.com> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
2012-08-22ds2781_battery: Convert to module_platform_driverDevendra Naga
module_platform_driver can be used to replace the platform_driver register and unregister functions, with the calls to module_init and module_exit, i.e. all the code that is doing like the below static int __init mymod_init(void) { return platform_driver_register(&drv_operations); } static void __exit mymod_exit(void) { platform_driver_unregister(&drv_operations); } module_init(mymod_init); module_exit(mymod_exit); can be replaced with module_platform_driver(drv_operations)... Signed-off-by: Devendra Naga <develkernel412222@gmail.com> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
2012-07-31Merge tag 'for-v3.6' of git://git.infradead.org/battery-2.6Linus Torvalds
Pull battery updates from Anton Vorontsov: "The tag contains just a few battery-related changes for v3.6. It's is all pretty straightforward, except one thing. One of our patches added thermal support for power supply class, but thermal/ subsystem changed under our feet. We (well, Stephen, that is) caught the issue and it was decided[1] that I'd just delay the battery pull request, and then will fix it up by merging upstream back into battery tree at the specific commit. That's not all though: another[2] small fixup for thermal subsystem was needed to get rid of a warning in power supply subsystem (the warning was not drivers/power's "fault", the thermal registration function just needed a proper const annotation, which is also done by a small commit on top of the merge. So, to sum this up: - The 'master' branch of the battery tree was in the -next tree for weeks, was never rebased, altered etc. It should be all OK; - Although, for-v3.6 tag contains the 'master' branch + merge + the warning fix. [1] http://lkml.org/lkml/2012/6/19/23 [2] http://lkml.org/lkml/2012/6/18/28" * tag 'for-v3.6' of git://git.infradead.org/battery-2.6: (23 commits) thermal: Constify 'type' argument for the registration routine olpc-battery: update CHARGE_FULL_DESIGN property for BYD LiFe batteries olpc-battery: Add VOLTAGE_MAX_DESIGN property charger-manager: Fix build break related to EXTCON lp8727_charger: Move header file into platform_data directory power_supply: Add min/max alert properties for CAPACITY, TEMP, TEMP_AMBIENT bq27x00_battery: Add support for BQ27425 chip charger-manager: Set current limit of regulator for over current protection charger-manager: Use EXTCON Subsystem to detect charger cables for charging test_power: Add VOLTAGE_NOW and BATTERY_TEMP properties test_power: Add support for USB AC source gpio-charger: Use cansleep version of gpio_set_value bq27x00_battery: Add support for power average and health properties sbs-battery: Don't trigger false supply_changed event twl4030_charger: Allow charger to control the regulator that feeds it twl4030_charger: Add backup-battery charging twl4030_charger: Fix some typos max17042_battery: Support CHARGE_COUNTER power supply attribute smb347-charger: Add constant charge and current properties power_supply: Add constant charge_current and charge_voltage properties ...
2012-06-17ds2781_battery: w1_ds2781_read() should be staticAnton Vorontsov
This patch fixes the following sparse warning: CHECK drivers/power/ds2781_battery.c drivers/power/ds2781_battery.c:72:5: warning: symbol 'w1_ds2781_read' was not declared. Should it be static? Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
2012-06-13W1: split master mutex to avoid deadlocks.NeilBrown
The 'mutex' in struct w1_master is use for two very different purposes. Firstly it protects various data structures such as the list of all slaves. Secondly it protects the w1 buss against concurrent accesses. This can lead to deadlocks when the ->probe code called while adding a slave needs to talk on the bus, as is the case for power_supply devices. ds2780 and ds2781 drivers contain a work around to track which process hold the lock simply to avoid this deadlock. bq27000 doesn't have that work around and so deadlocks. There are other possible deadlocks involving sysfs. When removing a device the sysfs s_active lock is held, so the lock that protects the slave list must take precedence over s_active. However when access power_supply attributes via sysfs, the s_active lock must take precedence over the lock that protects accesses to the bus. So to avoid deadlocks between w1 slaves and sysfs, these must be two separate locks. Making them separate means that the work around in ds2780 and ds2781 can be removed. So this patch: - adds a new mutex: "bus_mutex" which serialises access to the bus. - takes in mutex in w1_search and ds1wm_search while they access the bus for searching. The mutex is dropped before calling the callback which adds the slave. - changes all slaves to use bus_mutex instead of mutex to protect access to the bus - removes w1_ds2790_io_nolock and w1_ds2781_io_nolock, and the related code from drivers/power/ds278[01]_battery.c which calls them. Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-05ds2781_battery: Use DS2781_PARAM_EEPROM_SIZE and DS2781_USER_EEPROM_SIZEAxel Lin
Since we have defined DS2781_PARAM_EEPROM_SIZE and DS2781_USER_EEPROM_SIZE, use them to simplify the code. Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
2012-03-08DS2781 Maxim Stand-Alone Fuel Gauge battery and w1 slave driversRenata Sayakhova
Signed-off-by: Renata Sayakhova <rsayakhova@gmail.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>