leds: class: If no default trigger is given, make hw_control trigger the default trigger

If a hw_control_trigger is defined, it's usually desirable to make it
the default trigger. Therefore make it the default trigger, except
the driver explicitly set a default trigger.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/f33543de-3800-488f-a779-1fa282614462@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>

leds: class: Don't expose color sysfs entry

The commit c7d80059b086 ("leds: class: Store the color index in struct
led_classdev") introduced a new sysfs entry "color" that is commonly
created for the led classdev. Unfortunately, this conflicts with the
"color" sysfs entry of already existing drivers such as Logitech HID
or System76 ACPI drivers. The driver probe fails due to the conflict,
hence it leads to a severe regression with the missing keyboard, for
example.

This patch reverts partially the change in the commit above for
removing the led class color sysfs entries again for addressing the
regressions. The newly introduced led_classdev.color field is kept as
it's already used by other driver.

Fixes: c7d80059b086 ("leds: class: Store the color index in struct led_classdev")
Reported-by: Johannes Penßel <johannes.penssel@gmail.com>
Closes: https://lore.kernel.org/r/b5646db3-acff-45aa-baef-df3f660486fb@gmail.com
Link: https://bugzilla.kernel.org/show_bug.cgi?id=218045
Link: https://bugzilla.kernel.org/show_bug.cgi?id=218155
Link: https://bugzilla.suse.com/show_bug.cgi?id=1217172
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20231121162359.9332-1-tiwai@suse.de
Signed-off-by: Lee Jones <lee@kernel.org>

leds: Make leds_class a static const structure

Now that the driver core allows for struct class to be in read-only
memory, move the leds_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at boot time.

Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Link: https://lore.kernel.org/r/20230810174905.7997-1-ivan.orlov0322@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>

leds: class: Store the color index in struct led_classdev

Store the color of the LED so that it is not lost after the LED's
name has been composed. This color information can then be exposed to
the user space or used by the LED consumer.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
Link: https://lore.kernel.org/r/20230728153731.3742339-3-jjhiblot@traphandler.com
Signed-off-by: Lee Jones <lee@kernel.org>

leds: Provide devm_of_led_get_optional()

Add an optional variant of devm_of_led_get(). It behaves the same as
devm_of_led_get() except where the LED doesn't exist. In this case,
instead of returning -ENOENT, the function returns NULL.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20230728153731.3742339-2-jjhiblot@traphandler.com
Signed-off-by: Lee Jones <lee@kernel.org>

led: led-class: Read max-brightness from devicetree

Normally, the maximum brightness is determined by the hardware, and this
property is not required. This property is used to set a software limit.
It could happen that an LED is made so bright that it gets damaged or
causes damage due to restrictions in a specific system, such as mounting
conditions.
Note that this flag is mainly used for PWM-LEDs, where it is not possible
to map brightness to current. Drivers for other controllers should use
led-max-microamp.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Astrid Rost <astrid.rost@axis.com>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Link: https://lore.kernel.org/r/20230703130313.548519-3-astrid.rost@axis.com
Signed-off-by: Lee Jones <lee@kernel.org>

leds: Replace all non-returning strlcpy with strscpy

strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230523021451.2406362-1-azeemshaikh38@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>

driver core: class: remove module * from class_create()

The module pointer in class_create() never actually did anything, and it
shouldn't have been requred to be set as a parameter even if it did
something. So just remove it and fix up all callers of the function in
the kernel tree at the same time.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

leds: led-core: Fix refcount leak in of_led_get()

class_find_device_by_of_node() calls class_find_device(), it will take
the reference, use the put_device() to drop the reference when not need
anymore.

Fixes: 699a8c7c4bd3 ("leds: Add of_led_get() and led_put()")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20221220121807.1543790-1-linmq006@gmail.com

leds: led-class: Add generic [devm_]led_get()

Add a generic [devm_]led_get() method which can be used on both devicetree
and non devicetree platforms to get a LED classdev associated with
a specific function on a specific device, e.g. the privacy LED associated
with a specific camera sensor.

Note unlike of_led_get() this takes a string describing the function
rather then an index. This is done because e.g. camera sensors might
have a privacy LED, or a flash LED, or both and using an index
approach leaves it unclear what the function of index 0 is if there is
only 1 LED.

This uses a lookup-table mechanism for non devicetree platforms.
This allows the platform code to map specific LED class_dev-s to a specific
device,function combinations this way.

For devicetree platforms getting the LED by function-name could be made
to work using the standard devicetree pattern of adding a -names string
array to map names to the indexes.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230120114524.408368-5-hdegoede@redhat.com

leds: led-class: Add __devm_led_get() helper

Add a __devm_led_get() helper which registers a passed in led_classdev
with devm for unregistration.

This is a preparation patch for adding a generic (non devicetree specific)
devm_led_get() function.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230120114524.408368-4-hdegoede@redhat.com

leds: led-class: Add led_module_get() helper

Split out part of of_led_get() into a generic led_module_get() helper
function.

This is a preparation patch for adding a generic (non devicetree specific)
led_get() function.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230120114524.408368-3-hdegoede@redhat.com

leds: led-class: Add missing put_device() to led_put()

led_put() is used to "undo" a successful of_led_get() call,
of_led_get() uses class_find_device_by_of_node() which returns
a reference to the device which must be free-ed with put_device()
when the caller is done with it.

Add a put_device() call to led_put() to free the reference returned
by class_find_device_by_of_node().

And also add a put_device() in the error-exit case of try_module_get()
failing.

Fixes: 699a8c7c4bd3 ("leds: Add of_led_get() and led_put()")
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230120114524.408368-2-hdegoede@redhat.com

leds: led-core: Update fwnode with device_set_node

Update a newly created device's fwnode and of_node pointers using the
recently added device_set_node helper. This keeps some firmware node
specifics out of led-class and should help tracking future changes
regarding device firmware node updates.

Signed-off-by: Sander Vanheule <sander@svanheule.net>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

leds: leds-core: Implement the retain-state-shutdown property

Read the retain-state-shutdown device tree property to set the
existing LED_RETAIN_AT_SHUTDOWN flag. Then check the flag when
unregistering, and if set, don't set the brightness to OFF. This
is useful for systems that want to keep the HW state of the LED
across reboots.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

leds: class: The -ENOTSUPP should never be seen by user space

Drop the bogus error code and let of_led_get() to take care about absent
of_node.

Fixes: e389240ad992 ("leds: Add managed API to get a LED from a device driver")
Cc: Jean-Jacques Hiblot <jjhiblot@ti.com>
Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

leds: led-class: Fix incorrectly documented param 'dev'

Fixes the following W=1 kernel build warning(s):

drivers/leds/led-class.c:521: warning: Function parameter or member 'dev' not described in 'devm_led_classdev_unregister'
drivers/leds/led-class.c:521: warning: Excess function parameter 'parent' description in 'devm_led_classdev_unregister'

Cc: Pavel Machek <pavel@ucw.cz>
Cc: John Lenz <lenz@cs.wisc.edu>
Cc: Richard Purdie <rpurdie@openedhand.com>
Cc: linux-leds@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

leds: led-core: Get rid of enum led_brightness

This gets rid of enum led_brightness in the main led files,
because it is deprecated, and an unsigned int can be used instead.

We can get rid of led_brightness completely and
patches can also be supplied for the other drivers' files.

Signed-off-by: Abanoub Sameh <abanoubsameh@protonmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

leds: parse linux,default-trigger DT property in LED core

Do the parsing of `linux,default-trigger` DT property to LED core.
Currently it is done in many different drivers and the code is repeated.

This patch removes the parsing from 23 drivers:
an30259a, aw2013, bcm6328, bcm6358, cr0014114, el15203000, gpio,
is31fl32xx, lm3532, lm36274, lm3692x, lm3697, lp50xx, lp8860, lt3593,
max77650, mt6323, ns2, pm8058, pwm, syscon, tlc591xx and turris-omnia.

There is one driver in drivers/input which parses this property on it's
own. I shall send a separate patch there after this is applied.

There are still 8 drivers that parse this property on their own because
they do not pass the led_init_data structure to the registering
function. I will try to refactor those in the future.

Signed-off-by: Marek Behún <marek.behun@nic.cz>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

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: 81fe8e5b73e3 ("leds: core: Add led_set_brightness_nosleep{nopm} functions")
Signed-off-by: Pavel Machek <pavel@ucw.cz>

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: bb4e9af0348d ("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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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: 1afcadfcd184 ("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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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: a96aa64cb572 ("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>

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>

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: 73e1ab41a80d (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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

Revert "leds: convert blink timer to workqueue"

This reverts commit 8b37e1bef5a6b60e949e28a4db3006e4b00bd758.

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

leds: fixed a coding style issue.

Fixed a coding style issue relating to trailing
white space error found by checkpatch.pl tool in drivers/leds/led-class.c

Signed-off-by: Jeffrin Jose <ahiliation@yahoo.co.in>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>

leds: simple_strtoul() cleanup

led-class.c and ledtrig-timer.c still use simple_strtoul(). Change them
to use kstrtoul() instead of obsolete simple_strtoul().

Also fix the existing int ret declaration to be ssize_t to match the
return type for _store functions in ledtrig-timer.c.

Signed-off-by: Shuah Khan <shuahkhan@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

led-class: change back LEDS_CLASS to tristate instead of bool

After moving some core functions to led-core.c, led-class.c can be built
as module again.

Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Acked-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

driver-core: remove sysdev.h usage.

The sysdev.h file should not be needed by any in-kernel code, so remove
the .h file from these random files that seem to still want to include
it.

The sysdev code will be going away soon, so this include needs to be
removed no matter what.

Cc: Jiandong Zheng <jdzheng@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: David Brown <davidb@codeaurora.org>
Cc: Daniel Walker <dwalker@fifo99.com>
Cc: Bryan Huntsman <bryanh@codeaurora.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: "Venkatesh Pallipadi
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>

Revert "leds: save the delay values after a successful call to blink_set()"

Revert commit 6123b0e274503a0d3588e84fbe07c9aa01bfaf5d.

The problem this patch intends to solve has alreadqy been fixed by
commit 7a5caabd090b ("drivers/leds/ledtrig-timer.c: fix broken sysfs
delay handling").

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Cc: Antonio Ospite <ospite@studenti.unina.it>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: turn the blink_timer off before starting to blink

Depending on the implementation of the hardware blinking function in
blink_set(), the led can support hardware blinking for some values of
delay_on and delay_off and fall-back to software blinking for some other
values.

Turning off the blink_timer unconditionally before starting to blink
make sure that a sequence like:

OFF
hardware blinking
software blinking
hardware blinking

does not leave the software blinking timer active.

Signed-off-by: Antonio Ospite <ospite@studenti.unina.it>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: <stable@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: save the delay values after a successful call to blink_set()

When calling the hardware blinking function implemented by blink_set(),
the delay_on and delay_off values are not preserved across calls.

Fix that and make the "timer" trigger work as expected when hardware
blinking is available.

BEFORE the fix:
$ cd /sys/class/leds/someled
$ echo timer > trigger
$ cat delay_on delay_off
0
0
$ echo 100 > delay_on
$ cat delay_on delay_off
0
0
$ echo 100 > delay_off
$ cat delay_on delay_off
0
0

AFTER the fix:
$ cd /sys/class/leds/someled
$ echo timer > trigger
$ cat delay_on delay_off
0
0
$ echo 100 > delay_on
$ cat delay_on delay_off
100
0
$ echo 100 > delay_off
$ cat delay_on delay_off
100
100

Signed-off-by: Antonio Ospite <ospite@studenti.unina.it>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: <stable@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: support automatic start of blinking with ledtrig-timer

By setting initial values blink_delay_on and blink_delay_off in a
led_classdev struct, this change starts the blinking when the led is
initialized.

With this patch, you can initialize blink_delay_on and blink_delay_off in
led_classdev with default_trigger set to "timer", and the led will start
up blinking. The current ledtrig-timer implementation ignores any initial
blink_delay_on/blink_delay_off settings, and requires setting
blink_delay_on/blink_delay_off (typically from userspace) before the led
blinks.

Signed-off-by: Esben Haabendal <eha@doredevelopment.dk>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

led_class: fix typo in blink API

When I added led_blink_set I had a typo: the return value of the hw
offload is a regular error code that is zero when succesful, and in that
case software emulation should not be used, rather than the other way
around.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Cc: Richard Purdie <rpurdie@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

led-class: always implement blinking

Currently, blinking LEDs can be awkward because it is not guaranteed that
all LEDs implement blinking. The trigger that wants it to blink then
needs to implement its own timer solution.

Rather than require that, add led_blink_set() API that triggers can use.
This function will attempt to use hw blinking, but if that fails
implements a timer for it. To stop blinking again, brightness_set() also
needs to be wrapped into API that will stop the software blink.

As a result of this, the timer trigger becomes a very trivial one, and
hopefully we can finally see triggers using blinking as well because it's
always easy to use.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: led-class: set permissions on max_brightness file to 0444

max_brightness is not writable, thus set permissions to 0444.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

leds: Fix race between LED device uevent and actual attributes creation

If we were to dynamically register/unregister leds and have udev or other
daemons handle the leds class uevents, we would be notified of the adding of a
new LED and if the daemon immediately tries to open one of the attributes of
the led device, it would fail with a "no such file or directory" error since
this the attributes are not yet created. Fix this by switching attributes to be
class-wide, such that the driver core will register these attributes with
device_add_attrs and then emit the kobject_uevent ADD signal.

Signed-off-by: Fainelli <ffainelli@freebox.fr>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

leds: led-class.c - Quiet boot messages

As each led device gets registered a kernel message gets printed. In
an embedded system with a number of leds this can produce a lot
of output that just looks like noise.

Change the message type to KERN_DEBUG since it might be useful
in the dmesg output "after" booting.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

tree-wide: convert open calls to remove spaces to skip_spaces() lib function

Makes use of skip_spaces() defined in lib/string.c for removing leading
spaces from strings all over the tree.

It decreases lib.a code size by 47 bytes and reuses the function tree-wide:
text data bss dec hex filename
64688 584 592 65864 10148 (TOTALS-BEFORE)
64641 584 592 65817 10119 (TOTALS-AFTER)

Also, while at it, if we see (*str && isspace(*str)), we can be sure to
remove the first condition (*str) as the second one (isspace(*str)) also
evaluates to 0 whenever *str == 0, making it redundant. In other words,
"a char equals zero is never a space".

Julia Lawall tried the semantic patch (http://coccinelle.lip6.fr) below,
and found occurrences of this pattern on 3 more files:
drivers/leds/led-class.c
drivers/leds/ledtrig-timer.c
drivers/video/output.c

@@
expression str;
@@

( // ignore skip_spaces cases
while (*str && isspace(*str)) { \(str++;\|++str;\) }
|
- *str &&
isspace(*str)
)

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Cc: Julia Lawall <julia@diku.dk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Neil Brown <neilb@suse.de>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: David Howells <dhowells@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: allow led-drivers to use a variable range of brightness values

This patch allows drivers to override the default maximum brightness value
of 255. We take care to preserve backwards-compatibility as much as
possible, so that user-space ABI doesn't change for existing drivers.
LED trigger code has also been updated to use the per-LED maximum.

Signed-off-by: Guennadi Liakhovetski <lg@denx.de>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

leds: Add suspend/resume to the core class

Add suspend/resume to the core class and remove all the now unneeded
code from various drivers. Originally the class code couldn't support
suspend/resume but since class_device can there is no reason for
each driver doing its own suspend/resume anymore.

leds: Fixup kdoc comment to match parameter names

Signed-off-by: Sven Wegener <sven.wegener@stealer.net>
Signed-off-by: Richard Purdie <rpurdie@intel.linux.com>

leds: Fix trigger registration race

Fix a race during trigger registration where we could try and use a lock
before it was initialised.

Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

leds: Fix leds-class.c comment

led_classdev_unregister() has no "__" prefix, remove it.

Signed-off-by: Qinghuang Feng <qhfeng.kernel@gmail.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

leds: Remove uneeded strlen calls

There's no need for the additional call to strlen(), we can directly
return the value returned by sprintf(). We now return a length value
that doesn't include the final '\0', but user space shouldn't bother
about it anyway.

Signed-off-by: Sven Wegener <sven.wegener@stealer.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

device create: misc: convert device_create_drvdata to device_create

Now that device_create() has been audited, rename things back to the
original call to be sane.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

LEDS: fix race in device_create

There is a race from when a device is created with device_create() and
then the drvdata is set with a call to dev_set_drvdata() in which a
sysfs file could be open, yet the drvdata will be NULL, causing all
sorts of bad things to happen.

This patch fixes the problem by using the new function,
device_create_drvdata().

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Remove duplicated unlikely() in IS_ERR()

Some drivers have duplicated unlikely() macros. IS_ERR() already has
unlikely() in itself.

This patch cleans up such pointless code.

Signed-off-by: Hirofumi Nakagawa <hnakagawa@miraclelinux.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Jeff Garzik <jeff@garzik.org>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: Add support to leds with readable status

Some led hardware allows drivers to query the led state, and this patch
adds a hook to let the led class take advantage of that information when
available.

Without this functionality, when access to the led hardware is not
exclusive (i.e. firmware or hardware might change its state behind the
kernel's back), reality goes out of sync with the led class' idea of what
the led is doing, which is annoying at best.

Behaviour for drivers that do not or cannot read the led status is
unchanged.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>

leds: disable triggers on brightness set

Disable any active triggers when the brightness attribute is
set to zero.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Márton Németh <nm127@freemail.hu>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>

PM: Remove destroy_suspended_device()

After 2.6.24 there was a plan to make the PM core acquire all device
semaphores during a suspend/hibernation to protect itself from
concurrent operations involving device objects. That proved to be
too heavy-handed and we found a better way to achieve the goal, but
before it happened, we had introduced the functions
device_pm_schedule_removal() and destroy_suspended_device() to allow
drivers to "safely" destroy a suspended device and we had adapted some
drivers to use them. Now that these functions are no longer necessary,
it seems reasonable to remove them and modify their users to use the
normal device unregistration instead.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

leds: add possibility to remove leds classdevs during suspend/resume

Make it possible to unregister a led classdev object in a safe way during a
suspend/resume cycle.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

leds: Fix leds_list_lock locking issues

Covert leds_list_lock to a rw_sempahore to match previous LED trigger
locking fixes, fixing lock ordering.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>

leds: Fix led trigger locking bugs

Convert part of the led trigger core from rw spinlocks to rw
semaphores. We're calling functions which can sleep from invalid
contexts otherwise. Fixes bug #9264.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>

leds: Convert from struct class_device to struct device

Convert the LEDs class from struct class_device to struct device
since class_device is scheduled for removal.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] drivers/led: handle sysfs errors

Signed-off-by: Jeff Garzik <jeff@garzik.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

kerneldoc-typo in led-class.c

Fixes a typo in led-class.c kerneldoc.

Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

Remove obsolete #include <linux/config.h>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

[PATCH] LED: Fix sysfs store function error handling

Fix the error handling of some LED _store functions. This corrects them to
return -EINVAL if the value is not numeric with an optional byte of trailing
whitespace.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] LED: add LED trigger tupport

Add support for LED triggers to the LED subsystem. "Triggers" are events
which change the state of an LED. Two kinds of trigger are available, simple
ones which can be added to exising code with minimum disruption and complex
ones for implementing new or more complex functionality.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] LED: add LED class

Add the foundations of a new LEDs subsystem. This patch adds a class which
presents LED devices within sysfs and allows their brightness to be
controlled.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>