Commit Graph

87 Commits

Author SHA1 Message Date
Kai-Heng Feng
302a085c20 leds: core: Flush scheduled work for system suspend
Sometimes LED won't be turned off by LED_CORE_SUSPENDRESUME flag upon
system suspend.

led_set_brightness_nopm() uses schedule_work() to set LED brightness.
However, there's no guarantee that the scheduled work gets executed
because no one flushes the work.

So flush the scheduled work to make sure LED gets turned off.

Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Fixes: 81fe8e5b73 ("leds: core: Add led_set_brightness_nosleep{nopm} functions")
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-07-12 10:10:37 +02:00
Ricardo Ribalda Delgado
64ed6588c2 leds: core: Fix warning message when init_data
The warning message when a led is renamed due to name collition can fail
to show proper original name if init_data is used. Eg:

[    9.073996] leds-gpio a0040000.leds_0: Led (null) renamed to red_led_1 due to name collision

Fixes: bb4e9af034 ("leds: core: Add support for composing LED class device names")
Signed-off-by: Ricardo Ribalda Delgado <ribalda@kernel.org>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-04-06 23:12:08 +02:00
Jean-Jacques Hiblot
7a349e8c53 leds: populate the device's of_node
If initialization data is available and its fwnode is actually a
of_node, store this information in the led device's structure. This
will allow the device to use or provide OF-based API such (devm_xxx).

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-01-06 00:20:22 +01:00
Jean-Jacques Hiblot
e389240ad9 leds: Add managed API to get a LED from a device driver
If the LED is acquired by a consumer device with devm_led_get(), it is
automatically released when the device is detached.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-01-06 00:20:18 +01:00
Tomi Valkeinen
699a8c7c4b leds: Add of_led_get() and led_put()
This patch adds basic support for a kernel driver to get a LED device.
This will be used by the led-backlight driver.

Only OF version is implemented for now, and the behavior is similar to
PWM's of_pwm_get() and pwm_put().

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-01-06 00:20:06 +01:00
Dan Murphy
4b83cf07d7 leds: core: Fix devm_classdev_match to reference correct structure
Fix the devm_classdev_match pointer initialization to the correct
structure type.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2019-11-03 17:38:51 +01:00
Akinobu Mita
11f7000221 leds: remove PAGE_SIZE limit of /sys/class/leds/<led>/trigger
Reading /sys/class/leds/<led>/trigger returns all available LED triggers.
However, the size of this file is limited to PAGE_SIZE because of the
limitation for sysfs attribute.

Enabling LED CPU trigger on systems with thousands of CPUs easily hits
PAGE_SIZE limit, and makes it impossible to see all available LED triggers
and which trigger is currently activated.

We work around it here by converting /sys/class/leds/<led>/trigger to
binary attribute, which is not limited by length. This is _not_ good
design, do not copy it.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Dan Murphy <dmurphy@ti.com>A
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2019-11-03 17:38:14 +01:00
Andy Shevchenko
1dbb9fb408 leds: Allow to call led_classdev_unregister() unconditionally
If in the certain driver the LED is optional, and it's a majority of them,
the call of led_classdev_unregister() still requires some additional
checks.

The usual pattern on unregistering is to check for NULL, but we also check
for IS_ERR() in case device_create_with_groups() fails.

The change will reduce a burden in a lot of drivers to repeatedly check
for above conditions.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-08-26 20:03:58 +02:00
Andy Shevchenko
fd81d7e946 leds: Switch to use fwnode instead of be stuck with OF one
There is no need to be stuck with OF node when we may use agnostic
firmware node instead.

It allows users to get property if needed independently of provider.

Note, some OF parts are left because %pfw [1] is in progress.

[1]: https://lore.kernel.org/patchwork/cover/1054863/

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-08-23 23:39:37 +02:00
Jacek Anaszewski
be7fc2cc86 Generic Device Lookup Helpers
Persistent tag for others to pull this branch from
 
 Based on patch series from Suzuki K Poulose <suzuki.poulose@arm.com>
 with Subject: [PATCH v3 0/7] drivers: Add generic device lookup helpers
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'generic_lookup_helpers' into for-next

Generic Device Lookup Helpers

Persistent tag for others to pull this branch from

Based on patch series from Suzuki K Poulose <suzuki.poulose@arm.com>
with Subject: [PATCH v3 0/7] drivers: Add generic device lookup helpers

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

* tag 'generic_lookup_helpers':
  platform: Add platform_find_device_by_driver() helper
  drivers: Add generic helper to match any device
  drivers: Introduce device lookup variants by ACPI_COMPANION device
  drivers: Introduce device lookup variants by device type
  drivers: Introduce device lookup variants by fwnode
  drivers: Introduce device lookup variants by of_node
  drivers: Introduce device lookup variants by name
2019-07-30 22:36:31 +02:00
Suzuki K Poulose
6cda08a20d drivers: Introduce device lookup variants by name
Add a helper to match the device name for device lookup. Also
reuse this generic exported helper for the existing bus_find_device_by_name().
and add similar variants for driver/class.

Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexander Aring <alex.aring@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Murphy <dmurphy@ti.com>
Cc: Harald Freudenberger <freude@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: linux-leds@vger.kernel.org
Cc: linux-rtc@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Cc: linux-wpan@vger.kernel.org
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Stefan Schmidt <stefan@datenfreihafen.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20190723221838.12024-2-suzuki.poulose@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-30 13:07:41 +02:00
Jacek Anaszewski
bb4e9af034 leds: core: Add support for composing LED class device names
Add generic support for composing LED class device name. The newly
introduced led_compose_name() function composes device name according
to either <color:function> or <devicename:color:function> pattern,
depending on the configuration of initialization data.

Backward compatibility with in-driver hard-coded LED class device
names is assured thanks to the default_label and devicename properties
of newly introduced struct led_init_data.

In case none of the aforementioned properties was found, then, for OF
nodes, the node name is adopted for LED class device name.

At the occassion of amending the Documentation/leds/leds-class.txt
unify spelling: colour -> color.

Alongside these changes added is a new tool - tools/leds/get_led_device_info.sh.
The tool allows retrieving details of a LED class device's parent device,
which proves that using vendor or product name for devicename part
of LED name doesn't convey any added value since that information had been
already available in sysfs. The script performs also basic validation
of a LED class device name.

Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Baolin Wang <baolin.wang@linaro.org>
Cc: Dan Murphy <dmurphy@ti.com>
Cc: Daniel Mack <daniel@zonque.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Oleh Kravchenko <oleg@kaa.org.ua>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Simon Shields <simon@lineageos.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
2019-07-25 20:07:52 +02:00
Jacek Anaszewski
b2b998c0f9 leds: class: Improve LED and LED flash class registration API
Replace of_led_classdev_register() with led_classdev_register_ext(), which
accepts easily extendable struct led_init_data, instead of the fixed
struct device_node argument. The latter can be now passed in an fwnode
property of the struct led_init_data.

The modification is driven by the need for passing additional arguments
required for the forthcoming generic mechanism for composing LED names.
Currently the LED name is conveyed in the "name" char pointer property of
the struct led_classdev. This is redundant since LED class device name
is accessible throughout the whole LED class device life time via
associated struct device's kobj->name property.

The change will not break any existing clients since the patch alters
also existing led_classdev{_flash}_register() macro wrappers, that pass
NULL in place of init_data, which leads to using legacy name
initialization path basing on the struct led_classdev's "name" property.

Three existing users of devm_of_led_classdev_registers() are modified
to use devm_led_classdev_register(), which will not impact their
operation since they in fact didn't need to pass struct device_node on
registration from the beginning.

Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Baolin Wang <baolin.wang@linaro.org>
Cc: Dan Murphy <dmurphy@ti.com>
Cc: Daniel Mack <daniel@zonque.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Oleh Kravchenko <oleg@kaa.org.ua>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Simon Shields <simon@lineageos.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
2019-07-25 20:07:50 +02:00
Thomas Gleixner
d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Pavel Machek
0db37915d9 leds: avoid races with workqueue
There are races between "main" thread and workqueue. They manifest
themselves on Thinkpad X60:

This should result in LED blinking, but it turns it off instead:

    root@amd:/data/pavel# cd /sys/class/leds/tpacpi\:\:power
    root@amd:/sys/class/leds/tpacpi::power# echo timer > trigger
    root@amd:/sys/class/leds/tpacpi::power# echo timer > trigger

It should be possible to transition from blinking to solid on by echo
0 > brightness; echo 1 > brightness... but that does not work, either,
if done too quickly.

Synchronization of the workqueue fixes both.

Fixes: 1afcadfcd1 ("leds: core: Use set_brightness_work for the blocking op")
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-05-02 22:54:51 +02:00
Luis Henriques
6d71021ab3 leds: class: ensure workqueue is initialized before setting brightness
An application can try to set brightness before all the initialization is
done, in particular before the workqueue is initialized with the call to
led_init_core().  Here's a WARNING easy to trigger:

[   36.780813] WARNING: CPU: 3 PID: 1411 at ../kernel/workqueue.c:1444 __queue_work+0x37b/0x420
[   36.780815] Modules linked in: ...
[   36.780868] CPU: 3 PID: 1411 Comm: systemd-backlig Not tainted 4.16.9-1-default #1 openSUSE Tumbleweed (unreleased)
[   36.780868] Hardware name: Dell Inc. Precision 5510/0N8J4R, BIOS 1.6.1 12/11/2017
[   36.780870] RIP: 0010:__queue_work+0x37b/0x420
[   36.780871] RSP: 0018:ffffaced048b7d78 EFLAGS: 00010086
[   36.780873] RAX: 0000000000000000 RBX: ffffffffb3f01440 RCX: 0000000000000000
[   36.780873] RDX: ffffffffc05a90d8 RSI: 0000000000000000 RDI: ffff8eac7dce2700
[   36.780874] RBP: ffff8ea547c16400 R08: ffff8ea547800000 R09: ffff8eac7dc22700
[   36.780875] R10: 0000000000000000 R11: 0000000000000040 R12: 0000000000000003
[   36.780876] R13: 0000000000000200 R14: ffffffffc05a90d0 R15: ffff8eac7dce8600
[   36.780877] FS:  00007f871e61cf40(0000) GS:ffff8eac7dcc0000(0000) knlGS:0000000000000000
[   36.780878] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   36.780879] CR2: 000055c91115e308 CR3: 0000000883ee0005 CR4: 00000000003606e0
[   36.780880] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   36.780880] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   36.780881] Call Trace:
[   36.780886]  queue_work_on+0x81/0x90
[   36.780889]  brightness_store+0x5d/0x90
[   36.780892]  kernfs_fop_write+0x105/0x180
[   36.780894]  __vfs_write+0x26/0x150
[   36.780897]  ? common_file_perm+0x51/0x150
[   36.780900]  ? security_file_permission+0x3c/0xb0
[   36.780901]  vfs_write+0xad/0x1a0
[   36.780903]  SyS_write+0x42/0x90
[   36.780906]  do_syscall_64+0x76/0x140
[   36.780908]  entry_SYSCALL_64_after_hwframe+0x42/0xb7
[   36.780910] RIP: 0033:0x7f871dd04c94
[   36.780910] RSP: 002b:00007ffeb3a57d38 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   36.780912] RAX: ffffffffffffffda RBX: 000055c91115c810 RCX: 00007f871dd04c94
[   36.780912] RDX: 0000000000000001 RSI: 000055c91115c810 RDI: 0000000000000004
[   36.780913] RBP: 00007ffeb3a57e10 R08: 0000000000000003 R09: 0000000000000000
[   36.780914] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
[   36.780914] R13: 000055c911158f30 R14: 000055c90f3a9a4e R15: 0000000000000004
[   36.780917] Code: 74 18 e8 49 80 00 00 48 85 c0 74 0e 48 8b 40 20 48 3b 68 08
0f 84 c2 fc ff ff 0f 0b 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 <0f> 0b e9
82 fd ff ff 83 cd 02 49 8d 57 60 e9 69 fd ff ff 80 3d
[   36.780942] ---[ end trace 1fce4edad54c4017 ]---

This patch initializes and acquires the led_access mutex early in the
of_led_classdev_register function, so that any application trying to write
to sysfs to set brightness will block until initialization ends.

Signed-off-by: Luis Henriques <lhenriques@suse.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2018-05-24 22:08:26 +02:00
Rafał Miłecki
442c609830 leds: core: add OF variants of LED registering functions
These new functions allow passing an additional device_node argument
that will be internally set for created LED device. Thanks to this LED
core code and triggers will be able to access DT node for reading extra
info.

The easiest solution for achieving this was reworking old functions to
more generic ones & adding simple defines for API compatibility.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2017-03-08 21:10:01 +01:00
Hans de Goede
0cb8eb30d4 leds: class: Add new optional brightness_hw_changed attribute
Some LEDs may have their brightness level changed autonomously
(outside of kernel control) by hardware / firmware. This commit
adds support for an optional brightness_hw_changed attribute to
signal such changes to userspace (if a driver can detect them):

What:		/sys/class/leds/<led>/brightness_hw_changed
Date:		January 2017
KernelVersion:	4.11
Description:
		Last hardware set brightness level for this LED. Some LEDs
		may be changed autonomously by hardware/firmware. Only LEDs
		where this happens and the driver can detect this, will
		have this file.

		This file supports poll() to detect when the hardware
		changes the brightness.

		Reading this file will return the last brightness level set
		by the hardware, this may be different from the current
		brightness.

Drivers which want to support this, simply add LED_BRIGHT_HW_CHANGED to
their flags field and call led_classdev_notify_brightness_hw_changed()
with the hardware set brightness when they detect a hardware / firmware
triggered brightness change.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2017-01-29 19:59:42 +01:00
Hans de Goede
a9c6ce57ec led: core: Use atomic bit-field for the blink-flags
All the LED_BLINK* flags are accessed read-modify-write from e.g.
led_set_brightness and led_blink_set_oneshot while both
set_brightness_work and the blink_timer may be running.

If these race then the modify step done by one of them may be lost,
switch the LED_BLINK* flags to a new atomic work_flags bit-field
to avoid this race.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2016-11-22 12:07:05 +01:00
David Lechner
eb1ce74699 leds: Use macro for max device node name size
Use a macro instead of hard-coding the max device node name size. The
uleds driver introduced a macro for this value, so using it.

Signed-off-by: David Lechner <david@lechnology.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2016-11-22 12:07:02 +01:00
Heiner Kallweit
d84d80f38f leds: core: avoid error message when a USB LED device is unplugged
When a USB LED device is unplugged the remove call chain calls
led_classdev_unregister which tries to switch the LED off.
As the device has been removed already this results in a ENODEV
error message in dmesg.
Avoid this error message by ignoring ENODEV in calls from
led_classdev_unregister if the LED device is flagged as pluggable.

Therefore a new flag LED_HW_PLUGGABLE was introduced which should be set by
all LED drivers handling pluggable LED devices (mainly USB LED devices).

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2016-03-14 09:22:20 +01:00
Milo Kim
d1aa577f5e leds: turn off the LED and wait for completion on unregistering LED class device
Workqueue, 'set_brightness_work' is used for scheduling brightness control.
This workqueue is canceled when the LED class device is unregistered.
Currently, LED subsystem handles like below.

  cancel_work_sync(&led_cdev->set_brightness_work)
  led_set_brightness(led_cdev, LED_OFF)

However, this could be a problem.
Workqueue is going to be canceled but LED device needs to be off.
The worst case is null pointer access due to scheduling a workqueue.

LED module is loaded.
  LED driver private data is allocated by using devm_zalloc().

LED module is unloaded.
  led_classdev_unregister() is called.
    cancel_work_sync()
      led_set_brightness(led_cdev, LED_OFF)
        schedule_work() if LED driver uses brightness_set_blocking()
        In the meantime, driver private data will be freed.

        ..scheduling..

        brightness_set_blocking() callback is invoked.
          For the brightness control, LED driver tries to access private
          data but resource is removed!

To avoid this problem, LED subsystem should turn off the brightness first
and wait for completion.

  led_set_brightness(led_cdev, LED_OFF)
  flush_work(&led_cdev->set_brightness_work)

It guarantees that LED driver turns off the brightness prior to
resource management.

Cc: linux-leds@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2016-01-04 09:57:37 +01:00
Jacek Anaszewski
13ae79bbe4 leds: core: Drivers shouldn't enforce SYNC/ASYNC brightness setting
This patch removes SET_BRIGHTNESS_ASYNC and SET_BRIGHTNESS_SYNC flags.
led_set_brightness() now calls led_set_brightness_nosleep() instead of
choosing between sync and async op basing on the flags defined by the
driver.

From now on, if a user wants to make sure that brightness will be set
synchronously, they have to use led_set_brightness_sync() API. It is now
being made publicly available since it has become apparent that it is
a caller who should decide whether brightness is to be set in
a synchronous or an asynchronous way.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
2016-01-04 09:57:31 +01:00
Jacek Anaszewski
81fe8e5b73 leds: core: Add led_set_brightness_nosleep{nopm} functions
This patch adds led_set_brightness_nosleep() and led_set_brightness_nopm()
functions, that guarantee setting LED brightness in a non-blocking way.
The latter is used from pm_ops context and doesn't modify the brightness
cached in the struct led_classdev. Its execution always ends up with
a call to brightness setting op - either directly or through
a set_brightness_work, regardless of LED_SUSPENDED flag state.

The patch also replaces led_set_brightness_async() with
led_set_brightness_nosleep() in all places where the most vital was setting
brightness in a non sleeping way but not necessarily asynchronously, which
is not needed for non-blocking drivers.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
2016-01-04 09:57:30 +01:00
Jacek Anaszewski
757b06ae04 leds: core: Move LED core callbacks out of led-class.c
Since the API for controlling LED brightness and blinking is defined in
the LED core, move the related timer and work callbacks to the led-core.c,
and initialize them through a new led_core_init API.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Pavel Machek <pavel@ucw.cz>
2015-11-03 08:59:22 +01:00
Ricardo Ribalda Delgado
e5b5a61fcb leds/led-class: Add missing put_device()
Devices found by class_find_device must be freed with put_device().
Otherwise the reference count will not work properly.

Fixes: a96aa64cb5 ("leds/led-class: Handle LEDs with the same name")
Reported-by: Alan Tull <delicious.quinoa@gmail.com>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2015-08-28 14:06:19 +02:00
Linus Torvalds
13d45f79a2 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds
Pull LED subsystem updates from Bryan Wu:
 "In this cycle, we finished to merge patches for LED Flash class
  driver.

  Other than that we have some bug fixes and new drivers for LED
  controllers"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds: (33 commits)
  leds:lp55xx: fix firmware loading error
  leds: fix max77693-led build errors
  leds: fix aat1290 build errors
  leds: aat1290: pass flags parameter to devm_gpiod_get
  leds: ktd2692: pass flags parameter to devm_gpiod_get
  drivers/leds: don't use module_init in non-modular leds-cobalt-raq.c
  leds: aat1290: add support for V4L2 Flash sub-device
  DT: aat1290: Document handling external strobe sources
  leds: max77693: add support for V4L2 Flash sub-device
  media: Add registration helpers for V4L2 flash sub-devices
  v4l: async: Add a pointer to of_node to struct v4l2_subdev, match it
  Documentation: leds: Add description of v4l2-flash sub-device
  leds: add BCM6358 LED driver
  leds: add DT binding for BCM6358 LED controller
  leds: fix brightness changing when software blinking is active
  Documentation: leds-lp5523: describe master fader attributes
  leds: lp5523: add master_fader support
  leds: leds-gpio: Allow compile test if !GPIOLIB
  leds: leds-gpio: Add missing #include <linux/of.h>
  gpiolib: Add missing dummies for the unified device properties interface
  ...
2015-07-01 19:09:11 -07:00
Stas Sergeev
76931edd54 leds: fix brightness changing when software blinking is active
The following sequence:
echo timer >/sys/class/leds/<name>/trigger
echo 1 >/sys/class/leds/<name>/brightness
should change the ON brightness for blinking.
The function led_set_brightness() was mistakenly initiating the
delayed blink stop procedure, which resulted in no blinking with
the timer trigger still active.

This patch fixes the problem by changing led_set_brightness()
to not initiate the delayed blink stop when brightness is not 0.

CC: Richard Purdie <rpurdie@rpsys.net>
CC: Kyungmin Park <kyungmin.park@samsung.com>
CC: linux-leds@vger.kernel.org
CC: linux-kernel@vger.kernel.org

Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Stas Sergeev <stsp@users.sourceforge.net>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2015-05-25 13:26:47 -07:00
Grygorii Strashko
084609bf72 leds / PM: fix hibernation on arm when gpio-led used with CPU led trigger
Setting a dev_pm_ops suspend/resume pair of callbacks but not a set of
hibernation callbacks means those pm functions will not be
called upon hibernation - that leads to system crash on ARM during
freezing if gpio-led is used in combination with CPU led trigger.
It may happen after freeze_noirq stage (GPIO is suspended)
and before syscore_suspend stage (CPU led trigger is suspended)
- usually when disable_nonboot_cpus() is called.

Log:
  PM: noirq freeze of devices complete after 1.425 msecs
  Disabling non-boot CPUs ...
    ^ system may crash or stuck here with message (TI AM572x)

  WARNING: CPU: 0 PID: 3100 at drivers/bus/omap_l3_noc.c:148 l3_interrupt_handler+0x22c/0x370()
  44000000.ocp:L3 Custom Error: MASTER MPU TARGET L4_PER1_P3 (Idle): Data Access in Supervisor mode during Functional access

  CPU1: shutdown
    ^ or here

Fix this by using SIMPLE_DEV_PM_OPS, which appropriately
assigns the suspend and hibernation callbacks and move
led_suspend/led_resume under CONFIG_PM_SLEEP to avoid
build warnings.

Fixes: 73e1ab41a8 (leds: Convert led class driver from legacy pm ops to dev_pm_ops)
Signed-off-by: Grygorii Strashko <Grygorii.Strashko@linaro.org>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: 3.11+ <stable@vger.kernel.org> # 3.11+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-12 23:58:24 +02:00
Sakari Ailus
ccdc45075a leds: Don't treat the LED name as a format string
The LED name was wrongly interpreted as format string. Stop doing that.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
2015-03-30 14:26:32 -07:00
Sakari Ailus
6f06c7f87c leds: Use log level warn instead of info when telling about a name clash
The LED names are expected to be unique in the system. Use KERN_WARNING log
level to notify the user about the matter.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
2015-03-30 14:26:25 -07:00
Ricardo Ribalda Delgado
a96aa64cb5 leds/led-class: Handle LEDs with the same name
The current code expected that every LED had an unique name. This is a
legit expectation when the device tree can no be modified or extended.
But with device tree overlays this requirement can be easily broken.

This patch finds out if the name is already in use and adds the suffix
_1, _2... if not.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2015-03-30 11:55:57 -07:00
Bjorn Andersson
ca1bb4ee4c leds: Introduce devres helper for led_classdev_register
(cooloney@gmail.com: add _unregister function into the document)

Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2015-03-09 13:43:41 -07:00
Jacek Anaszewski
7aea8389a7 leds: Add LED Flash class extension to the LED subsystem
Some LED devices support two operation modes - torch and flash.
This patch provides support for flash LED devices in the LED subsystem
by introducing new sysfs attributes and kernel internal interface.
The attributes being introduced are: flash_brightness, flash_strobe,
flash_timeout, max_flash_timeout, max_flash_brightness, flash_fault,
flash_sync_strobe and available_sync_leds. All the flash related
features are placed in a separate module.

The modifications aim to be compatible with V4L2 framework requirements
related to the flash devices management. The design assumes that V4L2
sub-device can take of the LED class device control and communicate
with it through the kernel internal interface. When V4L2 Flash sub-device
file is opened, the LED class device sysfs interface is made
unavailable.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2015-01-26 14:59:08 -08:00
Julia Lawall
137fe48d39 leds: Use setup_timer
Convert a call to init_timer and accompanying intializations of
the timer's data and function fields to a call to setup_timer.

A simplified version of the semantic match that fixes this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression t,f,d;
@@

-init_timer(&t);
+setup_timer(&t,f,d);
-t.function = f;
-t.data = d;
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2015-01-14 10:40:20 -08:00
Jacek Anaszewski
4d71a4a12b leds: Add support for setting brightness in a synchronous way
There are use cases when setting a LED brightness has to
have immediate effect (e.g. setting a torch LED brightness).
This patch extends LED subsystem to support such operations.
The LED subsystem internal API __led_set_brightness is changed
to led_set_brightness_async and new led_set_brightness_sync API
is added.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-11-14 14:29:35 -08:00
Jacek Anaszewski
acd899e4f3 leds: implement sysfs interface locking mechanism
Add a mechanism for locking LED subsystem sysfs interface.
This patch prepares ground for addition of LED Flash Class
extension, whose API will be integrated with V4L2 Flash API.
Such a fusion enforces introducing a locking scheme, which
will secure consistent access to the LED Flash Class device.

The mechanism being introduced allows for disabling LED
subsystem sysfs interface by calling led_sysfs_disable function
and enabling it by calling led_sysfs_enable. The functions
alter the LED_SYSFS_DISABLE flag state and must be called
under mutex lock. The state of the lock is checked with use
of led_sysfs_is_disabled function. Such a design allows for
providing immediate feedback to the user space on whether
the LED Flash Class device is available or is under V4L2 Flash
sub-device control.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-11-14 14:29:35 -08:00
Jacek Anaszewski
3ef7de5304 leds: Improve and export led_update_brightness
led_update_brightness helper function used to be exploited only locally
in the led-class.c module, where its result was being passed to the
brightness_show sysfs callback. With the introduction of v4l2-flash
subdevice the same functionality becomes required for reading current
brightness from a LED device. This patch adds checking of return value
of the brightness_get callback and moves the led_update_brightness()
function to the LED subsystem public API.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-09-12 14:01:54 -07:00
Jacek Anaszewski
3841961269 leds: avoid using DEVICE_ATTR macro for max_brightness attribute
Make definition of the brightness related sysfs attributes
consistent. The modification entails change of the function
name: led_max_brightness_show -> max_brightness_show

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-09-11 16:55:26 -07:00
Jacek Anaszewski
047133066e leds: Reorder include directives
Reorder include directives so that they are arranged
in alphabetical order.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-09-11 16:55:25 -07:00
Jiri Kosina
9067359faf Revert "leds: convert blink timer to workqueue"
This reverts commit 8b37e1bef5.

It's broken as it changes led_blink_set() in a way that it can now sleep
(while synchronously waiting for workqueue to be cancelled). That's a
problem, because it's possible that this function gets called from atomic
context (tpt_trig_timer() takes a readlock and thus disables preemption).

This has been brought up 3 weeks ago already [1] but no proper fix has
materialized, and I keep seeing the problem since 3.17-rc1.

[1] https://lkml.org/lkml/2014/8/16/128

 BUG: sleeping function called from invalid context at kernel/workqueue.c:2650
 in_atomic(): 1, irqs_disabled(): 0, pid: 2335, name: wpa_supplicant
 5 locks held by wpa_supplicant/2335:
  #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff814c7c92>] rtnl_lock+0x12/0x20
  #1:  (&wdev->mtx){+.+.+.}, at: [<ffffffffc06e649c>] cfg80211_mgd_wext_siwessid+0x5c/0x180 [cfg80211]
  #2:  (&local->mtx){+.+.+.}, at: [<ffffffffc0817dea>] ieee80211_prep_connection+0x17a/0x9a0 [mac80211]
  #3:  (&local->chanctx_mtx){+.+.+.}, at: [<ffffffffc08081ed>] ieee80211_vif_use_channel+0x5d/0x2a0 [mac80211]
  #4:  (&trig->leddev_list_lock){.+.+..}, at: [<ffffffffc081e68c>] tpt_trig_timer+0xec/0x170 [mac80211]
 CPU: 0 PID: 2335 Comm: wpa_supplicant Not tainted 3.17.0-rc3 #1
 Hardware name: LENOVO 7470BN2/7470BN2, BIOS 6DET38WW (2.02 ) 12/19/2008
  ffff8800360b5a50 ffff8800751f76d8 ffffffff8159e97f ffff8800360b5a30
  ffff8800751f76e8 ffffffff810739a5 ffff8800751f77b0 ffffffff8106862f
  ffffffff810685d0 0aa2209200000000 ffff880000000004 ffff8800361c59d0
 Call Trace:
  [<ffffffff8159e97f>] dump_stack+0x4d/0x66
  [<ffffffff810739a5>] __might_sleep+0xe5/0x120
  [<ffffffff8106862f>] flush_work+0x5f/0x270
  [<ffffffff810685d0>] ? mod_delayed_work_on+0x80/0x80
  [<ffffffff810945ca>] ? mark_held_locks+0x6a/0x90
  [<ffffffff81068a5f>] ? __cancel_work_timer+0x6f/0x100
  [<ffffffff810946ed>] ? trace_hardirqs_on_caller+0xfd/0x1c0
  [<ffffffff81068a6b>] __cancel_work_timer+0x7b/0x100
  [<ffffffff81068b0e>] cancel_delayed_work_sync+0xe/0x10
  [<ffffffff8147cf3b>] led_blink_set+0x1b/0x40
  [<ffffffffc081e6b0>] tpt_trig_timer+0x110/0x170 [mac80211]
  [<ffffffffc081ecdd>] ieee80211_mod_tpt_led_trig+0x9d/0x160 [mac80211]
  [<ffffffffc07e4278>] __ieee80211_recalc_idle+0x98/0x140 [mac80211]
  [<ffffffffc07e59ce>] ieee80211_idle_off+0xe/0x10 [mac80211]
  [<ffffffffc0804e5b>] ieee80211_add_chanctx+0x3b/0x220 [mac80211]
  [<ffffffffc08062e4>] ieee80211_new_chanctx+0x44/0xf0 [mac80211]
  [<ffffffffc080838a>] ieee80211_vif_use_channel+0x1fa/0x2a0 [mac80211]
  [<ffffffffc0817df8>] ieee80211_prep_connection+0x188/0x9a0 [mac80211]
  [<ffffffffc081c246>] ieee80211_mgd_auth+0x256/0x2e0 [mac80211]
  [<ffffffffc07eab33>] ieee80211_auth+0x13/0x20 [mac80211]
  [<ffffffffc06cb006>] cfg80211_mlme_auth+0x106/0x270 [cfg80211]
  [<ffffffffc06ce085>] cfg80211_conn_do_work+0x155/0x3b0 [cfg80211]
  [<ffffffffc06cf670>] cfg80211_connect+0x3f0/0x540 [cfg80211]
  [<ffffffffc06e6148>] cfg80211_mgd_wext_connect+0x158/0x1f0 [cfg80211]
  [<ffffffffc06e651e>] cfg80211_mgd_wext_siwessid+0xde/0x180 [cfg80211]
  [<ffffffffc06e36c0>] ? cfg80211_wext_giwessid+0x50/0x50 [cfg80211]
  [<ffffffffc06e36dd>] cfg80211_wext_siwessid+0x1d/0x40 [cfg80211]
  [<ffffffff81584d0c>] ioctl_standard_iw_point+0x14c/0x3e0
  [<ffffffff810946ed>] ? trace_hardirqs_on_caller+0xfd/0x1c0
  [<ffffffff8158502a>] ioctl_standard_call+0x8a/0xd0
  [<ffffffff81584fa0>] ? ioctl_standard_iw_point+0x3e0/0x3e0
  [<ffffffff81584b76>] wireless_process_ioctl.constprop.10+0xb6/0x100
  [<ffffffff8158521d>] wext_handle_ioctl+0x5d/0xb0
  [<ffffffff814cfb29>] dev_ioctl+0x329/0x620
  [<ffffffff810946ed>] ? trace_hardirqs_on_caller+0xfd/0x1c0
  [<ffffffff8149c7f2>] sock_ioctl+0x142/0x2e0
  [<ffffffff811b0140>] do_vfs_ioctl+0x300/0x520
  [<ffffffff815a67fb>] ? sysret_check+0x1b/0x56
  [<ffffffff810946ed>] ? trace_hardirqs_on_caller+0xfd/0x1c0
  [<ffffffff811b03e1>] SyS_ioctl+0x81/0xa0
  [<ffffffff815a67d6>] system_call_fastpath+0x1a/0x1f
 wlan0: send auth to 00:0b:6b:3c:8c:e4 (try 1/3)
 wlan0: authenticated
 wlan0: associate with 00:0b:6b:3c:8c:e4 (try 1/3)
 wlan0: RX AssocResp from 00:0b:6b:3c:8c:e4 (capab=0x431 status=0 aid=2)
 wlan0: associated
 IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
 cfg80211: Calling CRDA for country: NA
 wlan0: Limiting TX power to 27 (27 - 0) dBm as advertised by 00:0b:6b:3c:8c:e4

 =================================
 [ INFO: inconsistent lock state ]
 3.17.0-rc3 #1 Not tainted
 ---------------------------------
 inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
 swapper/0/0 [HC0[0]:SC1[1]:HE1:SE0] takes:
  ((&(&led_cdev->blink_work)->work)){+.?...}, at: [<ffffffff810685d0>] flush_work+0x0/0x270
 {SOFTIRQ-ON-W} state was registered at:
   [<ffffffff81094dbe>] __lock_acquire+0x30e/0x1a30
   [<ffffffff81096c81>] lock_acquire+0x91/0x110
   [<ffffffff81068608>] flush_work+0x38/0x270
   [<ffffffff81068a6b>] __cancel_work_timer+0x7b/0x100
   [<ffffffff81068b0e>] cancel_delayed_work_sync+0xe/0x10
   [<ffffffff8147cf3b>] led_blink_set+0x1b/0x40
   [<ffffffffc081e6b0>] tpt_trig_timer+0x110/0x170 [mac80211]
   [<ffffffffc081ecdd>] ieee80211_mod_tpt_led_trig+0x9d/0x160 [mac80211]
   [<ffffffffc07e4278>] __ieee80211_recalc_idle+0x98/0x140 [mac80211]
   [<ffffffffc07e59ce>] ieee80211_idle_off+0xe/0x10 [mac80211]
   [<ffffffffc0804e5b>] ieee80211_add_chanctx+0x3b/0x220 [mac80211]
   [<ffffffffc08062e4>] ieee80211_new_chanctx+0x44/0xf0 [mac80211]
   [<ffffffffc080838a>] ieee80211_vif_use_channel+0x1fa/0x2a0 [mac80211]
   [<ffffffffc0817df8>] ieee80211_prep_connection+0x188/0x9a0 [mac80211]
   [<ffffffffc081c246>] ieee80211_mgd_auth+0x256/0x2e0 [mac80211]
   [<ffffffffc07eab33>] ieee80211_auth+0x13/0x20 [mac80211]
   [<ffffffffc06cb006>] cfg80211_mlme_auth+0x106/0x270 [cfg80211]
   [<ffffffffc06ce085>] cfg80211_conn_do_work+0x155/0x3b0 [cfg80211]
   [<ffffffffc06cf670>] cfg80211_connect+0x3f0/0x540 [cfg80211]
   [<ffffffffc06e6148>] cfg80211_mgd_wext_connect+0x158/0x1f0 [cfg80211]
   [<ffffffffc06e651e>] cfg80211_mgd_wext_siwessid+0xde/0x180 [cfg80211]
   [<ffffffffc06e36dd>] cfg80211_wext_siwessid+0x1d/0x40 [cfg80211]
   [<ffffffff81584d0c>] ioctl_standard_iw_point+0x14c/0x3e0
   [<ffffffff8158502a>] ioctl_standard_call+0x8a/0xd0
   [<ffffffff81584b76>] wireless_process_ioctl.constprop.10+0xb6/0x100
   [<ffffffff8158521d>] wext_handle_ioctl+0x5d/0xb0
   [<ffffffff814cfb29>] dev_ioctl+0x329/0x620
   [<ffffffff8149c7f2>] sock_ioctl+0x142/0x2e0
   [<ffffffff811b0140>] do_vfs_ioctl+0x300/0x520
   [<ffffffff811b03e1>] SyS_ioctl+0x81/0xa0
   [<ffffffff815a67d6>] system_call_fastpath+0x1a/0x1f
 irq event stamp: 493416
 hardirqs last  enabled at (493416): [<ffffffff81068a5f>] __cancel_work_timer+0x6f/0x100
 hardirqs last disabled at (493415): [<ffffffff81067e9f>] try_to_grab_pending+0x1f/0x160
 softirqs last  enabled at (493408): [<ffffffff81053ced>] _local_bh_enable+0x1d/0x50
 softirqs last disabled at (493409): [<ffffffff81054c75>] irq_exit+0xa5/0xb0

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock((&(&led_cdev->blink_work)->work));
   <Interrupt>
     lock((&(&led_cdev->blink_work)->work));

  *** DEADLOCK ***

 2 locks held by swapper/0/0:
  #0:  (((&tpt_trig->timer))){+.-...}, at: [<ffffffff810b4c50>] call_timer_fn+0x0/0x180
  #1:  (&trig->leddev_list_lock){.+.?..}, at: [<ffffffffc081e68c>] tpt_trig_timer+0xec/0x170 [mac80211]

 stack backtrace:
 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.17.0-rc3 #1
 Hardware name: LENOVO 7470BN2/7470BN2, BIOS 6DET38WW (2.02 ) 12/19/2008
  ffffffff8246eb30 ffff88007c203b00 ffffffff8159e97f ffffffff81a194c0
  ffff88007c203b50 ffffffff81599c29 0000000000000001 ffffffff00000001
  ffff880000000000 0000000000000006 ffffffff81a194c0 ffffffff81093ad0
 Call Trace:
  <IRQ>  [<ffffffff8159e97f>] dump_stack+0x4d/0x66
  [<ffffffff81599c29>] print_usage_bug+0x1f4/0x205
  [<ffffffff81093ad0>] ? check_usage_backwards+0x140/0x140
  [<ffffffff810944d3>] mark_lock+0x223/0x2b0
  [<ffffffff81094d60>] __lock_acquire+0x2b0/0x1a30
  [<ffffffff81096c81>] lock_acquire+0x91/0x110
  [<ffffffff810685d0>] ? mod_delayed_work_on+0x80/0x80
  [<ffffffffc081e5a0>] ? __ieee80211_get_rx_led_name+0x10/0x10 [mac80211]
  [<ffffffff81068608>] flush_work+0x38/0x270
  [<ffffffff810685d0>] ? mod_delayed_work_on+0x80/0x80
  [<ffffffff810945ca>] ? mark_held_locks+0x6a/0x90
  [<ffffffff81068a5f>] ? __cancel_work_timer+0x6f/0x100
  [<ffffffffc081e5a0>] ? __ieee80211_get_rx_led_name+0x10/0x10 [mac80211]
  [<ffffffff8109469d>] ? trace_hardirqs_on_caller+0xad/0x1c0
  [<ffffffffc081e5a0>] ? __ieee80211_get_rx_led_name+0x10/0x10 [mac80211]
  [<ffffffff81068a6b>] __cancel_work_timer+0x7b/0x100
  [<ffffffff81068b0e>] cancel_delayed_work_sync+0xe/0x10
  [<ffffffff8147cf3b>] led_blink_set+0x1b/0x40
  [<ffffffffc081e6b0>] tpt_trig_timer+0x110/0x170 [mac80211]
  [<ffffffff810b4cc5>] call_timer_fn+0x75/0x180
  [<ffffffff810b4c50>] ? process_timeout+0x10/0x10
  [<ffffffffc081e5a0>] ? __ieee80211_get_rx_led_name+0x10/0x10 [mac80211]
  [<ffffffff810b50ac>] run_timer_softirq+0x1fc/0x2f0
  [<ffffffff81054805>] __do_softirq+0x115/0x2e0
  [<ffffffff81054c75>] irq_exit+0xa5/0xb0
  [<ffffffff810049b3>] do_IRQ+0x53/0xf0
  [<ffffffff815a74af>] common_interrupt+0x6f/0x6f
  <EOI>  [<ffffffff8147b56e>] ? cpuidle_enter_state+0x6e/0x180
  [<ffffffff8147b732>] cpuidle_enter+0x12/0x20
  [<ffffffff8108bba0>] cpu_startup_entry+0x330/0x360
  [<ffffffff8158fb51>] rest_init+0xc1/0xd0
  [<ffffffff8158fa90>] ? csum_partial_copy_generic+0x170/0x170
  [<ffffffff81af3ff2>] start_kernel+0x44f/0x45a
  [<ffffffff81af399c>] ? set_init_arg+0x53/0x53
  [<ffffffff81af35ad>] x86_64_start_reservations+0x2a/0x2c
  [<ffffffff81af36a0>] x86_64_start_kernel+0xf1/0xf4

Cc: Vincent Donnefort <vdonnefort@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-09-02 10:02:13 -07:00
Vincent Donnefort
8b37e1bef5 leds: convert blink timer to workqueue
This patch converts the blink timer from led-core to workqueue which is more
suitable for this kind of non-priority operations. Moreover, timer may lead to
errors when a LED setting function use a scheduling function such as pinctrl
which is using mutex.

Signed-off-by: Vincent Donnefort <vdonnefort@gmail.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-07-03 12:02:14 -07:00
Johan Hovold
d0d480cce8 leds: add led-class attribute-group support
Allow led-class devices to be created with optional attribute groups.

This is needed in order to allow led drivers to create custom device
attributes in a race-free manner.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-06-25 14:55:03 -07:00
Greg Kroah-Hartman
5baa7503a7 leds: convert class code to use dev_groups
The dev_attrs field of struct class is going away soon, dev_groups
should be used instead.  This converts the led class code to use the
correct field.

Acked-by: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26 18:05:17 -07:00
Shuah Khan
73e1ab41a8 leds: Convert led class driver from legacy pm ops to dev_pm_ops
Convert drivers/leds/led-class to use dev_pm_ops for power management and
remove Legacy PM ops hooks. With this change, led class registers
suspend/resume callbacks via class->pm (dev_pm_ops) instead of Legacy
class->suspend/resume. When __device_suspend() runs call-backs, it will
find class->pm ops for the led class.

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2013-06-20 17:36:45 -07:00
Sachin Kamat
d23e7b8b61 leds: led-class: Fix checkpatch warning
Fixes the following checkpatch warning:
WARNING: Prefer netdev_dbg(netdev, ... then dev_dbg(dev, ... then pr_debug(...  to printk(KERN_DEBUG ...
FILE: leds/led-class.c:214:
	printk(KERN_DEBUG "Registered led device: %s\n",

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2012-11-27 14:49:25 -08:00
Fabio Baltieri
d23a22a74f leds: delay led_set_brightness if stopping soft-blink
Delay execution of led_set_brightness() if need to stop soft-blink
timer.

This allows led_set_brightness to be called in hard-irq context even if
soft-blink was activated on that LED.

Signed-off-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
2012-09-11 18:32:40 +08:00
Shuah Khan
19cd67e2d5 leds: Rename led_brightness_set() to led_set_brightness()
Rename leds external interface led_brightness_set() to led_set_brightness().
This is the second phase of the change to reduce confusion between the
leds internal and external interfaces that set brightness. With this change,
now the external interface is led_set_brightness(). The first phase renamed
the internal interface led_set_brightness() to __led_set_brightness().
There are no changes to the interface implementations.

Signed-off-by: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
2012-07-24 07:52:34 +08:00
Shuah Khan
0da3e65ba8 leds: Rename led_set_brightness() to __led_set_brightness()
Rename leds internal interface led_set_brightness() to __led_set_brightness()
to reduce confusion between led_set_brightness() and the external interface
led_brightness_set(). led_brightness_set() cancels the timer and then calls
led_set_brightness().

Signed-off-by: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
2012-07-24 07:52:34 +08:00
Fabio Baltieri
5bb629c504 leds: add oneshot blink functions
Add two new functions, led_blink_set_oneshot and
led_trigger_blink_oneshot, to be used by triggers for one-shot blink of
led devices.

This is implemented extending the existing software-blink code, and uses
the same timer and handler function.

The behavior of the code is to do a blink-on, blink-off sequence when
the function is called, ignoring other calls until the sequence is
completed so that the leds keep blinking at constant rate if the
functions are called repeatedly.

This is meant to be used by drivers which needs to trigger on sporadic
event, but doesn't have clear busy/idle trigger points.

After the blink sequence the led remains off. This behavior can be
inverted setting the "invert" argument, which blink the led off, than on
and leave the led on after the sequence.

(bryan.wu@canonical.com: rebase to commit 'leds: don't disable blinking
when writing the same value to delay_on or delay_off')

Signed-off-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Acked-by: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
2012-07-24 07:52:34 +08:00