user/sven/linux.git/include/linux/power_supply.h, branch v4.14.235

power: remove possible deadlock when unregistering power_supply

2018-10-04T00:00:47Z

[ Upstream commit 3ffa6583e24e1ad1abab836d24bfc9d2308074e5 ] If a device gets removed right after having registered a power_supply node, we might enter in a deadlock between the remove call (that has a lock on the parent device) and the deferred register work. Allow the deferred register work to exit without taking the lock when we are in the remove state. Stack trace on a Ubuntu 16.04: [16072.109121] INFO: task kworker/u16:2:1180 blocked for more than 120 seconds. [16072.109127] Not tainted 4.13.0-41-generic #46~16.04.1-Ubuntu [16072.109129] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [16072.109132] kworker/u16:2 D 0 1180 2 0x80000000 [16072.109142] Workqueue: events_power_efficient power_supply_deferred_register_work [16072.109144] Call Trace: [16072.109152] __schedule+0x3d6/0x8b0 [16072.109155] schedule+0x36/0x80 [16072.109158] schedule_preempt_disabled+0xe/0x10 [16072.109161] __mutex_lock.isra.2+0x2ab/0x4e0 [16072.109166] __mutex_lock_slowpath+0x13/0x20 [16072.109168] ? __mutex_lock_slowpath+0x13/0x20 [16072.109171] mutex_lock+0x2f/0x40 [16072.109174] power_supply_deferred_register_work+0x2b/0x50 [16072.109179] process_one_work+0x15b/0x410 [16072.109182] worker_thread+0x4b/0x460 [16072.109186] kthread+0x10c/0x140 [16072.109189] ? process_one_work+0x410/0x410 [16072.109191] ? kthread_create_on_node+0x70/0x70 [16072.109194] ret_from_fork+0x35/0x40 [16072.109199] INFO: task test:2257 blocked for more than 120 seconds. [16072.109202] Not tainted 4.13.0-41-generic #46~16.04.1-Ubuntu [16072.109204] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [16072.109206] test D 0 2257 2256 0x00000004 [16072.109208] Call Trace: [16072.109211] __schedule+0x3d6/0x8b0 [16072.109215] schedule+0x36/0x80 [16072.109218] schedule_timeout+0x1f3/0x360 [16072.109221] ? check_preempt_curr+0x5a/0xa0 [16072.109224] ? ttwu_do_wakeup+0x1e/0x150 [16072.109227] wait_for_completion+0xb4/0x140 [16072.109230] ? wait_for_completion+0xb4/0x140 [16072.109233] ? wake_up_q+0x70/0x70 [16072.109236] flush_work+0x129/0x1e0 [16072.109240] ? worker_detach_from_pool+0xb0/0xb0 [16072.109243] __cancel_work_timer+0x10f/0x190 [16072.109247] ? device_del+0x264/0x310 [16072.109250] ? __wake_up+0x44/0x50 [16072.109253] cancel_delayed_work_sync+0x13/0x20 [16072.109257] power_supply_unregister+0x37/0xb0 [16072.109260] devm_power_supply_release+0x11/0x20 [16072.109263] release_nodes+0x110/0x200 [16072.109266] devres_release_group+0x7c/0xb0 [16072.109274] wacom_remove+0xc2/0x110 [wacom] [16072.109279] hid_device_remove+0x6e/0xd0 [hid] [16072.109284] device_release_driver_internal+0x158/0x210 [16072.109288] device_release_driver+0x12/0x20 [16072.109291] bus_remove_device+0xec/0x160 [16072.109293] device_del+0x1de/0x310 [16072.109298] hid_destroy_device+0x27/0x60 [hid] [16072.109303] usbhid_disconnect+0x51/0x70 [usbhid] [16072.109308] usb_unbind_interface+0x77/0x270 [16072.109311] device_release_driver_internal+0x158/0x210 [16072.109315] device_release_driver+0x12/0x20 [16072.109318] usb_driver_release_interface+0x77/0x80 [16072.109321] proc_ioctl+0x20f/0x250 [16072.109325] usbdev_do_ioctl+0x57f/0x1140 [16072.109327] ? __wake_up+0x44/0x50 [16072.109331] usbdev_ioctl+0xe/0x20 [16072.109336] do_vfs_ioctl+0xa4/0x600 [16072.109339] ? vfs_write+0x15a/0x1b0 [16072.109343] SyS_ioctl+0x79/0x90 [16072.109347] entry_SYSCALL_64_fastpath+0x24/0xab [16072.109349] RIP: 0033:0x7f20da807f47 [16072.109351] RSP: 002b:00007ffc422ae398 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [16072.109353] RAX: ffffffffffffffda RBX: 00000000010b8560 RCX: 00007f20da807f47 [16072.109355] RDX: 00007ffc422ae3a0 RSI: 00000000c0105512 RDI: 0000000000000009 [16072.109356] RBP: 0000000000000000 R08: 00007ffc422ae3e0 R09: 0000000000000010 [16072.109357] R10: 00000000000000a6 R11: 0000000000000246 R12: 0000000000000000 [16072.109359] R13: 00000000010b8560 R14: 00007ffc422ae2e0 R15: 0000000000000000 Reported-and-tested-by: Richard Hughes Tested-by: Aaron Skomra Signed-off-by: Benjamin Tissoires Fixes: 7f1a57fdd6cb ("power_supply: Fix possible NULL pointer dereference on early uevent") Signed-off-by: Sebastian Reichel Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

power: supply: Add power_supply_set_input_current_limit_from_supplier helper

2017-08-29T10:24:52Z

On some devices the USB Type-C port power (USB PD 2.0) negotiation is done by a separate port-controller IC, while the current limit is controlled through another (charger) IC. It has been decided to model this by modelling the external Type-C power brick (adapter/charger) as a power-supply class device which supplies the charger-IC, with its voltage-now and current-max representing the negotiated voltage and max current draw. This commit adds a power_supply_set_input_current_limit_from_supplier helper function which charger power-supply drivers can call to get the max-current from their supplier and have this applied through their set_property call-back to their input-current-limit. Signed-off-by: Hans de Goede Signed-off-by: Sebastian Reichel

power: supply: core: Add power_supply_prop_precharge

2017-06-08T14:29:28Z

Battery chargers use POWER_SUPPLY_PROP_PRECHARGE_CURRENT Clarify related item POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT Signed-off-by: Liam Breck Signed-off-by: Sebastian Reichel

power: supply: core: Add power_supply_battery_info and API

2017-06-08T14:29:28Z

power_supply_get_battery_info() reads battery data from devicetree. struct power_supply_battery_info provides battery data to drivers. Its fields correspond to elements in enum power_supply_property. Drivers may surface battery data in sysfs via corresponding POWER_SUPPLY_PROP_* fields. Signed-off-by: Matt Ranostay Signed-off-by: Liam Breck Signed-off-by: Sebastian Reichel

power: supply: Add Apple Brick ID power supply type

2017-06-08T11:05:22Z

Apple currently supports three very common USB chargers: https://www.apple.com/power-adapters/ These chargers implement a proprietary Apple method for advertising 1A, 2.1A, and 2.4A at 5V called "Brick ID". In addition, 3rd parties implement the same charging method in many charging accessories that work with iOS devices. Devices that have charger detection chips such as the Pericom PI3USB9281, eg. Google Chromebook Pixel 2015, are capable of detecting these chargers, so let's add a type to facilicate passing that info up to userspace. This adds a separate power supply type for Apple's proprietary "Brick ID" charging method. Signed-off-by: Benson Leung Signed-off-by: Sebastian Reichel

power_supply: fix return value of get_property

2016-07-01T20:44:34Z

power_supply_get_property() should ideally return -EAGAIN if it is called while the power_supply is being registered. There was no way previously to determine if use_cnt == 0 meant that the power_supply wasn't fully registered yet, or if it had already been unregistered. Add a new boolean to the power_supply struct to simply show if registration is completed. Lastly, modify the check in power_supply_show_property() to also ignore -EAGAIN when so it doesn't complain about not returning the property. Signed-off-by: Rhyland Klein Signed-off-by: Sebastian Reichel

power_supply: Add types for USB Type C and PD chargers

2016-02-15T06:02:32Z

This adds power supply types for USB chargers defined in the USB Type-C Specification 1.1 and in the USB Power Delivery Specification Revision 2.0 V1.1. The following are added : POWER_SUPPLY_TYPE_USB_TYPE_C, /* Type C Port */ POWER_SUPPLY_TYPE_USB_PD, /* Power Delivery Port */ POWER_SUPPLY_TYPE_USB_PD_DRP, /* PD Dual Role Port */ Signed-off-by: Benson Leung [tomeu: remove the mention to Type C from the comments] Signed-off-by: Tomeu Vizoso Reviewed-by: Alec Berg Reviewed-by: Vincent Palatin Reviewed-by: Todd Broch Signed-off-by: Sebastian Reichel

power: Add devm_power_supply_get_by_phandle() helper function

2015-06-10T14:15:54Z

This commit adds a resource-managed version of the power_supply_get_by_phandle() function. Signed-off-by: Hans de Goede Signed-off-by: Sebastian Reichel

power_supply: sysfs: Bring back write to writeable properties

2015-06-10T14:10:59Z

The fix for NULL pointer exception related to calling uevent for not finished probe caused to set all writeable properties as non-writeable. This was caused by checking if property is writeable before the initial increase of power supply usage counter and in the same time using wrapper over property_is_writeable(). The wrapper returns ENODEV if the usage counter is still 0. The call trace looked like: device probe: power_supply_register() use_cnt = 0; device_add() create sysfs entries power_supply_attr_is_visible() power_supply_property_is_writeable() if (use_cnt == 0) return -ENODEV; use_cnt++; Replace the usage of wrapper with direct call to property_is_writeable() from driver. This should be safe call during device probe because implementations of this callback just return 0/1 for different properties and they do not access any of the driver's internal data. Fixes: 8e59c7f23410 ("power_supply: Fix NULL pointer dereference during bq27x00_battery probe") Signed-off-by: Krzysztof Kozlowski Signed-off-by: Sebastian Reichel

power_supply: Fix possible NULL pointer dereference on early uevent

2015-05-21T13:41:09Z

Don't call the power_supply_changed() from power_supply_register() when parent is still probing because it may lead to accessing parent too early. In bq27x00_battery this caused NULL pointer exception because uevent of power_supply_changed called back the the get_property() method provided by the driver. The get_property() method accessed pointer which should be returned by power_supply_register(). Starting from bq27x00_battery_probe(): di->bat = power_supply_register() power_supply_changed() kobject_uevent() power_supply_uevent() power_supply_show_property() power_supply_get_property() bq27x00_battery_get_property() dereference of di->bat which is NULL here The dereference of di->bat (value returned by power_supply_register()) is the currently visible problem. However calling back the methods provided by driver before ending the probe may lead to accessing other driver-related data which is not yet initialized. The call to power_supply_changed() is postponed till probing ends - mutex of parent device is released. Reported-by: H. Nikolaus Schaller Signed-off-by: Krzysztof Kozlowski Fixes: 297d716f6260 ("power_supply: Change ownership from driver to core") Tested-By: Dr. H. Nikolaus Schaller Signed-off-by: Sebastian Reichel