Commit Graph

57 Commits

Author SHA1 Message Date
Hui Wang d8960dfb9d leds: pwm: Clear the led structure before parsing each child node
I defined 2 leds in the device tree, in the 1st led node, the
max-brightness is set to 248, while in the 2nd led node, I
mis-spelled the max-brightness to max-brighttness, but the driver
is still able to get the max-brightness 248 for the 2nd node,  that
is because the led structure is not cleared before parsing each child
node.

	pwmleds {
		compatible = "pwm-leds";

		pwm-green {
			...
			max-brightness = <248>;
		};

		pwm-red {
		        ...
			max-brighttness = <128>;
		};

Signed-off-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20221220073335.393489-1-hui.wang@canonical.com
2023-01-30 08:00:51 +00:00
Denis Osterland-Heim 3d3d65bd27 leds: pwm: add support for default-state device property
This patch adds support for "default-state" devicetree property, which
allows to defer pwm init to first use of led.

This allows to configure the PWM early in bootloader to let the LED
blink until an application in Linux userspace sets something different.

Signed-off-by: Denis Osterland-Heim <Denis.Osterland@diehl.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2021-08-18 08:27:31 +02:00
Andy Shevchenko 95138e0127 leds: pwm: Make error handling more robust
It's easy to miss necessary clean up, e.g. firmware node reference counting,
during error path in ->probe(). Make it more robust by moving to a single
point of return.

Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2021-05-28 12:00:16 +02:00
Alexander Dahl 19d2e0cef0 leds: pwm: Remove platform_data support
Since commit 141f15c66d ("leds: pwm: remove header") that platform
interface is not usable from outside and there seems to be no in tree
user anymore.  All in-tree users of the leds-pwm driver seem to use DT
currently.  Getting rid of the old platform interface allows the
leds-pwm driver to switch over from 'devm_led_classdev_register()' to
'devm_led_classdev_register_ext()'.

Signed-off-by: Alexander Dahl <post@lespocky.de>
Cc: Denis Osterland-Heim <denis.osterland@diehl.com>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-10-07 12:02:58 +02:00
Marek Behún c49d6cab0d 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>
2020-09-26 21:56:43 +02:00
Alexander Dahl de73f275a0 leds: pwm: Allow automatic labels for DT based devices
If LEDs are configured through device tree and the property 'label' is
omitted, the label is supposed to be generated from the properties
'function' and 'color' if present.  While this works fine for e.g. the
'leds-gpio' driver, it did not for 'leds-pwm'.

The reason is, you get this label naming magic only if you add a LED
device through 'devm_led_classdev_register_ext()' and pass a pointer to
the current device tree node.

For the following node from dts the LED appeared as 'led-5' in sysfs
before and as 'red:debug' after this change.

        pwm_leds {
                compatible = "pwm-leds";

                led-5 {
                        function = LED_FUNCTION_DEBUG;
                        color = <LED_COLOR_ID_RED>;
                        pwms = <&pwm0 2 10000000 0>;
                        max-brightness = <127>;

                        linux,default-trigger = "heartbeat";
                        panic-indicator;
                };
        };

Signed-off-by: Alexander Dahl <post@lespocky.de>
Cc: Marek Behún <marek.behun@nic.cz>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-09-26 21:56:38 +02:00
Krzysztof Kozlowski 7e8da60596 leds: pwm: Simplify with dev_err_probe()
Common pattern of handling deferred probe can be simplified with
dev_err_probe().  Less code and also it prints the error value.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-09-09 11:20:09 +02:00
Denis Osterland-Heim 44c606b005 leds: pwm: check result of led_pwm_set() in led_pwm_add()
led_pwm_set() now returns an error when setting the PWM fails.

Signed-off-by: Denis Osterland-Heim <Denis.Osterland@diehl.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-04-27 11:35:11 +02:00
Gustavo A. R. Silva 7bbec6c4b5 leds: leds-pwm: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-03-21 16:21:16 +01:00
Denis Osterland-Heim 4227685b4d leds: pwm: remove useless pwm_period_ns
This member seems to was a way to pass PWM period to the LED.
Since there is no header anymore, this is useless.

Signed-off-by: Denis Osterland-Heim <Denis.Osterland@diehl.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-03-21 16:17:53 +01:00
Denis Osterland-Heim 141f15c66d leds: pwm: remove header
The header is only used by leds_pwm.c, so move contents to leds_pwm.c
and remove it.
Apply minor changes suggested by checkpatch.
Remove deprecated and unused pwm_id member.

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>
2020-03-21 16:17:53 +01:00
Uwe Kleine-König dd47a83453 leds: pwm: convert to atomic PWM API
pwm_config(), pwm_enable() and pwm_disable() should get removed in the
long run. So update the driver to use the atomic API that is here to
stay.

A few side effects:

 - led_pwm_set() now returns an error when setting the PWM fails.
 - During .probe() the PWM isn't disabled implicitly by pwm_apply_args()
   any more.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Tested-by: Jeff LaBundy <jeff@labundy.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-02-26 21:49:39 +01:00
Uwe Kleine-König b43a8f01fc leds: pwm: simplify if condition
.pwm_period_ns is an unsigned integer. So when led->pwm_period_ns > 0
is false, we now assign 0 to a value that is already 0, so it doesn't
hurt and we can skip checking the actual value.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Tested-by: Jeff LaBundy <jeff@labundy.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-02-26 21:49:39 +01:00
Gustavo A. R. Silva d4b02200ae leds: pwm: Use struct_size() helper
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct led_pwm_priv {
	...
        struct led_pwm_data leds[0];
};

Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes.

So, replace the following function:

static inline size_t sizeof_pwm_leds_priv(int num_leds)
{
       return sizeof(struct led_pwm_priv) +
                     (sizeof(struct led_pwm_data) * num_leds);
}

with:

struct_size(priv, leds, count)

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-09-01 13:33:29 +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
Linus Torvalds 6e2bbb688a pwm: Changes for v5.3-rc1
This set of changes contains a new driver for SiFive SoCs as well as
 enhancements to the core (device links are used to track dependencies
 between PWM providers and consumers, support for PWM controllers via
 ACPI, sysfs will now suspend/resume PWMs that it has claimed) and
 various existing drivers.
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Merge tag 'pwm/for-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "This set of changes contains a new driver for SiFive SoCs as well as
  enhancements to the core (device links are used to track dependencies
  between PWM providers and consumers, support for PWM controllers via
  ACPI, sysfs will now suspend/resume PWMs that it has claimed) and
  various existing drivers"

* tag 'pwm/for-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (37 commits)
  pwm: fsl-ftm: Make sure to unlock mutex on failure
  pwm: fsl-ftm: Use write protection for prescaler & polarity
  pwm: fsl-ftm: More relaxed permissions for updating period
  pwm: atmel-hlcdc: Add compatible for SAM9X60 HLCDC's PWM
  pwm: bcm2835: Improve precision of PWM
  leds: pwm: Support ACPI via firmware-node framework
  pwm: Add support referencing PWMs from ACPI
  pwm: rcar: Remove suspend/resume support
  pwm: sysfs: Add suspend/resume support
  pwm: Add power management descriptions
  pwm: meson: Add documentation to the driver
  pwm: meson: Add support PWM_POLARITY_INVERSED when disabling
  pwm: meson: Don't cache struct pwm_state internally
  pwm: meson: Read the full hardware state in meson_pwm_get_state()
  pwm: meson: Simplify the calculation of the pre-divider and count
  pwm: meson: Move pwm_set_chip_data() to meson_pwm_request()
  pwm: meson: Add the per-channel register offsets and bits in a struct
  pwm: meson: Add the meson_pwm_channel data to struct meson_pwm
  pwm: meson: Pass struct pwm_device to meson_pwm_calc()
  pwm: meson: Don't duplicate the polarity internally
  ...
2019-07-09 08:57:45 -07:00
Nikolaus Voss 3f467ebe9e leds: pwm: Support ACPI via firmware-node framework
DT specific handling is replaced by firmware-node abstration to support
ACPI specification of PWM LEDS.

Example ASL:
Device (PWML)
{
    Name (_HID, "PRP0001")
    Name (_DSD, Package () {
          ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
          Package () { Package () {"compatible",
                                    Package () {"pwm-leds"}}}})

    Device (PWL0)
    {
        Name (_HID, "PRP0001")
        Name (_DSD, Package () {
              ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
              Package () {
                           Package () {"label", "alarm-led"},
                           Package () {"pwms", Package ()
                                       {\_SB_.PCI0.PWM, 0, 600000, 0}},
                           Package () {"linux,default-state", "off"}}})
    }
}

Signed-off-by: Nikolaus Voss <nikolaus.voss@loewensteinmedical.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-06-26 11:39:12 +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
Krzysztof Kozlowski cb14e6d6d8 leds: pwm: Use OF variant of LED registering function
The PWM leds can be instantiated from Device Tree so pass the
respective device node to LED core.  This provides the LED system with
proper device node and exposes it through uevent.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2018-12-08 18:59:47 +01:00
Krzysztof Kozlowski e5a0436dd0 leds: pwm: Simplify with resource-managed devm_led_classdev_register()
Simplify the exit path with resource-managed version of registering LED
class device.  The code should be functionally the same, except that on
device removal the led_pwm_priv->num_leds is not decremented to zero
(which should not have any effect as device is going away).

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2018-12-08 18:59:35 +01:00
Jerome Brunet 9aec30371f leds: pwm: silently error out on EPROBE_DEFER
When probing, if we fail to get the pwm due to probe deferal, we shouldn't
print an error message. Just be silent in this case.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2018-09-08 22:47:15 +02:00
Fabio Estevam e82e34ba30 leds: pwm: Remove unneeded header file
There is nothing provided by <linux/fb.h> that is used here,
so remove this unneeded header file.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2018-01-08 21:28:10 +01:00
Thierry Reding 247bde13b9 leds: pwm: Remove atomic code paths
PWM devices have all been marked as "might sleep" since v4.5. It no
longer makes sense to keep the alternative code paths around because
it is effectively dead code.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2017-01-04 09:37:56 +01:00
Boris Brezillon 1b50673dfa leds: pwm: Use pwm_get_args() where appropriate
The PWM framework has clarified the concept of reference PWM config (the
platform dependent config retrieved from the DT or the PWM lookup table)
and real PWM state.

Use pwm_get_args() when the PWM user wants to retrieve this reference
config and not the current state.

This is part of the rework allowing the PWM framework to support
hardware readout and expose real PWM state even when the PWM has just
been requested (before the user calls pwm_config/enable/disable()).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-05-17 14:45:02 +02:00
Uwe Kleine-König 49651c6c66 leds: pwm: fix driver description and make license match the header
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2016-01-04 09:57:37 +01:00
Markus Hofstaetter f16703360d leds: call led_pwm_set() in leds-pwm to enforce default LED_OFF
Some PWMs are disabled by default or the default pin setting
does not match the LED_OFF state (e.g., active-low leds).
Hence, the driver may end up reporting 0 brightness, but
the leds are actually on using full brightness, because
it never enforces its default configuration.
So enforce it by calling led_pwm_set() after successfully
registering the device.

Tested on a Phytec phyFLEX i.MX6Q board based on kernel
v3.19.5.

Signed-off-by: Markus Hofstaetter <markus.hofstaetter@ait.ac.at>
Tested-by: Markus Hofstaetter <markus.hofstaetter@ait.ac.at>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2016-01-04 09:57:36 +01:00
Jacek Anaszewski 9aa0762579 leds: pwm: remove work queue
Now the core implements the work queue, remove it from the drivers,
and switch to using brightness_set_blocking op.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: Raphael Assenat <raph@8d.com>
2016-01-04 09:57:35 +01:00
Sebastian Andrzej Siewior ed97604e36 leds: leds-pwm: drop one pwm_get_period() call
pwm_get_period() is called twice in case the child parameter is set. I
assume retrieving this parameter once is enough therefore this patch
removes the conditial invocation of pwm_get_period().

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2015-02-24 11:42:18 -08:00
Wolfram Sang 81902d5f65 leds: drop owner assignment from platform_drivers
A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20 16:20:43 +02:00
Linus Torvalds 7c574cf6ae Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds
Pull LED updates from Bryan Wu:
 "I just found merge window is open and I'm quite busy and almost forget
  to send out this pull request.  Thanks Russell and Alexandre ping me
  about this.

  So basically we got some clean up and leds-pwm fixing patches from
  Russell"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds:
  leds: Remove duplicated OOM message for individual driver
  drivers/leds: Replace __get_cpu_var use through this_cpu_ptr
  leds: lp55xx: add DT bindings for LP55231
  leds: 88pm860x: Fix missing refcount decrement for parent of_node
  leds: 88pm860x: Use of_get_child_by_name
  leds: leds-pwm: add DT support for LEDs wired to supply
  leds: leds-pwm: implement PWM inversion
  leds: leds-pwm: convert OF parsing code to use led_pwm_add()
  leds: leds-pwm: provide a common function to setup a single led-pwm device
  leds: pca9685: Remove leds-pca9685 driver
  dell-led: add mic mute led interface
2014-06-12 13:08:09 -07:00
Alexandre Belloni 81225bed32 leds: leds-pwm: retrieve configured PWM period
The PWM core is now able to initialize the PWM period from a lookup
table defined by board files. Use it if available and fallback to the
value supplied in pwm_period_ns.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2014-05-21 11:19:45 +02:00
Russell King b0571e7e4e leds: leds-pwm: add DT support for LEDs wired to supply
The non-DT driver allowed an active low property to be specified, but DT
is missing this in its description.  Add the property to the DT binding
document, making it optional.  It defaults to active high, which retains
compatibility with existing descriptions.

This should only be used for causes where the LED is wired to supply,
and the PWM does not sensibly support its own inversion.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-05-08 14:28:07 +08:00
Russell King d19a8a7078 leds: leds-pwm: implement PWM inversion
Some PWM outputs are wired such that the LED they're controlling is
connected to supply rather than ground.  These PWMs may not support
output inversion, or when they do, disabling the PWM may set the
PWM output low, causing a "brightness" value of zero to turn the LED
fully on.

The platform data for this driver already indicates that this was
thought about, and we have the "active_low" property there already.
However, the implementation for this is missing.

Add the trivial implementation for this feature.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-05-08 14:28:07 +08:00
Russell King b795e6d94f leds: leds-pwm: convert OF parsing code to use led_pwm_add()
Convert the OF parsing code to use the common PWM LED registration code,
which means we have a consistent method, and single point where the
registration happens for both paths.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-05-08 14:28:07 +08:00
Russell King 5f7b03dc2a leds: leds-pwm: provide a common function to setup a single led-pwm device
Provide a common function to setup a single led-pwm device, replacing
the platform data initialisation path with this function.  This allows
us to have a common method of creating these devices in a consistent
manner, which then allows us to place the probe failure cleanup in one
place.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-05-08 14:28:07 +08:00
Russell King 392369019e leds: leds-pwm: properly clean up after probe failure
When probing with DT, we add each LED one at a time.  If we find a LED
without a PWM device (because it is not available yet) we fail the
initialisation, unregister previous LEDs, and then by way of managed
resources, we free the structure.

The problem with this is we may have a scheduled and active work_struct
in this structure, and this results in a nasty kernel oops.

We need to cancel this work_struct properly upon cleanup - and the
cleanup we require is the same cleanup as we do when the LED platform
device is removed.  Rather than writing this same code three times,
move it into a separate function and use it in all three places.

Fixes: c971ff185f ("leds: leds-pwm: Defer led_pwm_set() if PWM can sleep")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-04-07 14:41:50 -07:00
Paul Gortmaker 7c7d2a26db drivers/leds: delete non-required instances of include <linux/init.h>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: linux-leds@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-02-27 09:56:56 -08:00
Olof Johansson 33fc94506b leds: pwm: Remove a warning on non-DT platforms
This removes a warning on non-DT-enabled platforms:

drivers/leds/leds-pwm.c: In function 'led_pwm_create_of':
drivers/leds/leds-pwm.c:88:22: warning: unused variable 'node'

Really caused by the local variable that is assigned to and then never
used. Just do away with the local var, it's not needed.

Technically this code path can never be entered without DT enabled,
since there's an earlier check about number of children in the calling
function, but the compiler can't see that.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-01-27 17:28:51 -08:00
Xiubo Li fc1aee038b leds: leds-pwm: fix duty time overflow.
Overflow maybe occurs when calculates the duty time. For instance,
the period time is 990000000ns, and the max_brightness is 127, when
setting the brightness to 12, the duty value will be 25906026ns, but
it should be 93543307ns.

Signed-off-by: Bryan Wu <cooloney@gmail.com>
2014-01-27 17:28:50 -08:00
Peter Ujfalusi aa1a6d6d74 leds: pwm: Fix for deferred probe in DT booted mode
We need to make sure that the error code from devm_of_pwm_get() is the one
the module returns in case of failure.
Restructure the code to make this possible for DT booted case.
With this patch the driver can ask for deferred probing when the board is
booted with DT.
Fixes for example omap4-sdp board's keyboard backlight led.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2013-12-02 11:53:17 -08:00
Sachin Kamat 1e08f72dd2 leds: pwm: Remove redundant of_match_ptr
The data structure of_match_ptr() protects is always compiled in.
Hence of_match_ptr() is not needed.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2013-10-22 10:57:34 -07:00
Jingoo Han 87aae1ea82 leds: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2013-08-26 17:22:11 -07:00
Florian Vaussard c971ff185f leds: leds-pwm: Defer led_pwm_set() if PWM can sleep
Call to led_pwm_set() can happen inside atomic context, like triggers.
If the PWM call can sleep, defer using a worker.

Signed-off-by: Florian Vaussard <florian.vaussard@epfl.ch>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2013-04-01 11:04:50 -07:00
Peter Ujfalusi 08541cbcc7 leds: leds-pwm: Add device tree bindings
The DT binding for the pwm-leds devices are similar to the gpio-leds type.
LEDs are represented as sub-nodes of the pwm-leds device.
The code for handling the DT boot is based on the code found in the
leds-gpio driver and adapted to use PWMs instead of GPIOs.
To avoid having custom cleanup code in case of DT boot the newly created
devm_of_pwm_get() API is used to get the correct PWM instance.

For usage see:
Documentation/devicetree/bindings/leds/leds-pwm.txt

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2013-02-01 17:47:05 -08:00
Peter Ujfalusi 8a66a57908 leds: leds-pwm: Simplify cleanup code
The code looks more nicer if we use:

while (i--)

instead:
if (i > 0)
	for (i = i - 1; i >= 0; i--)

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2013-02-01 17:47:05 -08:00
Peter Ujfalusi 0f86815ad0 leds: leds-pwm: Preparing the driver for device tree support
In order to be able to add device tree support for leds-pwm driver we need
to rearrange the data structures used by the drivers.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2013-02-01 17:47:04 -08:00
Peter Ujfalusi 9ea6cdac9b leds: leds-pwm: Convert to use devm_get_pwm
Update the driver to use the new API for requesting pwm so we can take
advantage of the pwm_lookup table to find the correct pwm to be used for the
LED functionality.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2013-02-01 17:47:04 -08:00
Linus Torvalds e81d372ff9 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds
Pull LED subsystem update from Bryan Wu.

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds: (47 commits)
  leds: leds-lp5521: return an error code on error in probe()
  leds: leds-clevo-mail: Use pr_* instead of printks
  leds: leds-rb532: Fix checkpatch errors
  leds: led-triggers: Fix checkpatch warnings
  leds: ledtrig-backlight: Fix checkpatch error
  leds: leds-wrap: Use <linux/io.h> instead of <asm/io.h>
  leds: leds-wm8350: Use dev_err instead of printk
  leds: leds-pwm: Fix checkpatch warning
  leds: leds-pca955x: Use dev_info instead of printk
  leds: leds-net48xx: Use linux/io.h instead of asm/io.h
  leds: leds-lt3593: Fix checkpatch warnings
  leds: leds-gpio: Use dev_info instead of printk
  leds: leds-da903x: Fix checkpatch error and warnings
  leds: leds-bd2802: Fix checkpatch warnings
  leds: leds-adp5520: Fix checkpatch warnings
  leds: led-class: Fix checkpatch warning
  leds: leds-ns2: use devm_gpio_request_one
  leds: leds-lt3593: use devm_gpio_request_one
  leds: leds-gpio: use devm_gpio_request_one
  leds: lp3944: Fix return value
  ...
2012-12-15 12:52:42 -08:00
Bill Pemberton 678e8a6be9 leds: remove use of __devexit
CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Jan-Simon Moeller <jansimon.moeller@gmx.de>
Acked-by: Bryan Wu <cooloney@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:35:06 -08:00
Bill Pemberton df07cf8126 leds: remove use of __devexit_p
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Jan-Simon Moeller <jansimon.moeller@gmx.de>
Acked-by: Bryan Wu <cooloney@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:33:20 -08:00