Even with the previous commit 27af8e2c90
("leds: trigger: fix potential deadlock with libata")
to this file, we still get lockdep unhappy, and Boqun
explained the report here:
https://lore.kernel.org/r/YNA+d1X4UkoQ7g8a@boqun-archlinux
Effectively, this means that the read_lock_irqsave() isn't
enough here because another CPU might be trying to do a
write lock, and thus block the readers.
This is all pretty messy, but it doesn't seem right that
the LEDs framework imposes some locking requirements on
users, in particular we'd have to make the spinlock in the
iwlwifi driver always disable IRQs, even if we don't need
that for any other reason, just to avoid this deadlock.
Since writes to the led_cdevs list are rare (and are done
by userspace), just switch the list to RCU. This costs a
synchronize_rcu() at removal time so we can ensure things
are correct, but that seems like a small price to pay for
getting lock-free iterations and no deadlocks (nor any
locking requirements imposed on users.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
This patch introduces a new function to read initial
default_state from fwnode.
Suggested-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Denis Osterland-Heim <Denis.Osterland@diehl.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
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>
Some LED controllers may come with an internal HW triggering mechanism
for the LED and the ability to switch between SW control and the
internal HW control. This includes most PHYs, various ethernet switches,
the Turris Omnia LED controller or AXP20X PMIC.
This adds support for registering such triggers.
This code is based on work by Pavel Machek <pavel@ucw.cz> and
Ondřej Jirman <megous@megous.com>.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
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>
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>
Update the leds.h structure documentation to define the
correct arguments.
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
extern is implied and is not needed in the header file.
Remove the extern keyword and re-align the code.
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
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>
Replace preprocessor macro aliases for legacy LED registration helpers
with inline functions. It will allow to avoid misleading compiler error
messages about missing symbol that actually wasn't explicitly used
in the code. It used to occur when CONFIG_LEDS_CLASS was undefined
and legacy (non-ext) function had been used in the code.
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
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>
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>
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>
Multiple LED triggers might need to access default pattern so add a
helper for that.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Pull LED updates from Jacek Anaszewski:
"There are several few-liners, where most of them are fixes and
improvments. One thing standing out is ground preparation for
inititializing trigger parameters via Device Tree.
We introduce LED_INIT_DEFAULT_TRIGGER flag for that purpose and set it
when default trigger is matched. It indicates that trigger should
parse DT properties to retrieve the initialization data when set as
default one"
* tag 'leds-for-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
led: triggers: Initialize LED_INIT_DEFAULT_TRIGGER if trigger is brought after class
led: triggers: Add LED_INIT_DEFAULT_TRIGGER flag
led: triggers: Break the for loop after default trigger is found
leds: pwm: Use OF variant of LED registering function
leds: pwm: Simplify with resource-managed devm_led_classdev_register()
leds: gpio: Drop unneeded manual of_node assignment
leds: 88pm860x: Use of_node_name_eq for node name comparisons
leds: powernv: add of_node_put()
Add the flag LED_INIT_DEFAULT_TRIGGER for indicating that trigger
being set is a default trigger for the LED class device, and
thus it should be initialized with settings provided in the fwnode.
Set the flag in the led_trigger_set_default(). It is expected to be
cleared in the activate() op of a trigger after trigger fwnode
initialization data is parsed and applied. This should happen only
once after LED class device registration, to allow leaving triggers
in the idle state on re-apply and let the users apply their own
settings without interference from the default ones.
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
This patch adds a new LED trigger for coupling the audio mixer change
with the LED on laptops or other devices. Currently there are two
trigger types, "audio-mute" and "audio-micmute".
The audio driver triggers the LED brightness change via
ledtrig_audio_set() call with the proper type (either mute or
mic-mute). OTOH, the consumers may call ledtrig_audio_get() for the
initial brightness value that may have been set by the audio driver
beforehand.
This new stuff will be used by HD-audio codec driver and some platform
drivers (thinkpad_acpi and dell-laptop, also upcoming huawei-wmi).
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This patch adds a new LED trigger that LED device can configure
to employ software or hardware pattern engine.
Consumers can write 'pattern' file to enable the software pattern
which alters the brightness for the specified duration with one
software timer.
Moreover consumers can write 'hw_pattern' file to enable the hardware
pattern for some LED controllers which can autonomously control
brightness over time, according to some preprogrammed hardware
patterns.
Signed-off-by: Raphael Teysseyre <rteysseyre@gmail.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
This helps to simplify modules that provide a simple led_trigger. It's
inspired by module_platform_driver, module_i2c_driver et al.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
As many triggers use device attributes, add support for these in
led_trigger_set which allows simplifying the drivers accordingly.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Given that activating a trigger can fail, let the callback return an
indication. This prevents to have a trigger active according to the
"trigger" sysfs attribute but not functional.
All users are changed accordingly to return 0 for now. There is no intended
change in behaviour.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
This adds two new disk triggers for triggering on reads
and writes respectively, named "disk-read" and "disk-write".
The use case comes from working on the D-Link DNS-313 NAS
box. This features an RGB LED for disk activity. with
these two triggers I can couple the green LED to read
activity and the red LED to write activity, which gives
the appropriate user feedback about what is happening
on the disk. When tested it gave exactly the feedback
desired.
The in-kernel interface is simply changed to pass a bool
indicating if the activity is write activity and update
each trigger (and the composite "disk-activity" trigger)
depending on what is passed in.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
This is for readability as well as to avoid checkpatch warnings when
adding new bit flag information in the future.
Signed-off-by: David Lin <dtwlin@google.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
