History log of /linux-master/drivers/leds/leds-lp55xx-common.c
Revision Date Author Comments
# 7c977019 18-Sep-2023 Stefan Eichenberger <eichest@gmail.com>

leds: lp55xx: Use gpiod_set_value_cansleep()

Use gpiod_set_value_cansleep in the init_device function. Without this
change, the driver may print a warning if the LP55xx enable pin is
connected to a GPIO chip which can sleep (e.g. a GPIO expander):

WARNING: CPU: 0 PID: 2719 at drivers/gpio/gpiolib.c:3051 gpiod_set_value+0x64/0xbc

Signed-off-by: Stefan Eichenberger <eichest@gmail.com>
Link: https://lore.kernel.org/r/20230918143238.75600-1-eichest@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>


# 54a7bef5 21-Apr-2023 Maarten Zanders <maarten.zanders@mind.be>

leds: lp55xx: Configure internal charge pump

The LP55xx range of devices have an internal charge pump which
can (automatically) increase the output voltage towards the
LED's, boosting the output voltage to 4.5V.

Implement this option from the devicetree. When the setting
is not present it will operate in automatic mode as before.

Tested on LP55231. Datasheet analysis shows that LP5521, LP5523
and LP8501 are identical in topology and are modified in the
same way.

Signed-off-by: Maarten Zanders <maarten.zanders@mind.be>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230421075305.37597-3-maarten.zanders@mind.be


# 3f6fb1cf 01-Dec-2022 ye xingchen <ye.xingchen@zte.com.cn>

leds: use sysfs_emit() to instead of scnprintf()

Replace the open-code with sysfs_emit() to simplify the code.

Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Signed-off-by: Pavel Machek <pavel@ucw.cz>


# fb0f4051 20-Oct-2022 Colin Ian King <colin.i.king@gmail.com>

leds: lp55xx: remove variable j

The variable j being incremented but it is never referenced,
it is redundant and can be removed.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>


# 9e87a8da 12-Dec-2021 Merlijn Wajer <merlijn@wizzup.org>

leds: lp55xx: initialise output direction from dts

Commit a5d3d1adc95f ("leds: lp55xx: Initialize enable GPIO direction to
output") attempts to fix this, but the fix did not work since at least
for the Nokia N900 the value needs to be set to HIGH, per the device
tree. So rather than hardcoding the value to a potentially invalid value
for some devices, let's set direction in lp55xx_init_device.

Fixes: a5d3d1adc95f ("leds: lp55xx: Initialize enable GPIO direction to output")
Fixes: 92a81562e695 ("leds: lp55xx: Add multicolor framework support to lp55xx")
Fixes: ac219bf3c9bd ("leds: lp55xx: Convert to use GPIO descriptors")
Signed-off-by: Merlijn Wajer <merlijn@wizzup.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>


# a5d3d1ad 10-May-2021 Doug Zobel <dougdev334@gmail.com>

leds: lp55xx: Initialize enable GPIO direction to output

The "Convert to use GPIO descriptors" commit changed the
initialization of the enable GPIO from GPIOF_DIR_OUT to
GPIOD_ASIS. This breaks systems where the GPIO does not
default to output. Changing the enable initialization
to GPIOD_OUT_LOW.

Signed-off-by: Doug Zobel <dougdev334@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>


# 2c677562 17-Sep-2020 Marek Behún <marek.behun@nic.cz>

leds: various: fix OF node leaks

Fix OF node leaks by calling of_node_put in
for_each_available_child_of_node when the cycle breaks or returns.

Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Nikita Travkin <nikitos.tr@gmail.com>
Cc: Milo Kim <milo.kim@ti.com>
Cc: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Not-for-stable: untested, theoretical, insignificant leaks


# 99a013c8 17-Sep-2020 Marek Behún <marek.behun@nic.cz>

leds: various: use only available OF children

Various drivers count and iterate over OF children nodes via
of_get_child_count and for_each_child_of_node. Instead they should use
of_get_available_child_count and for_each_available_child_of_node, so
that if a given node has the `status` property set to `disabled`, the
child will be ignored.

Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Andrey Utkin <andrey_utkin@fastmail.com>
Cc: Baolin Wang <baolin.wang7@gmail.com>
Cc: Baolin Wang <baolin.wang@linaro.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christian Mauderer <oss@c-mauderer.de>
Cc: Chunyan Zhang <zhang.lyra@gmail.com>
Cc: Dan Murphy <dmurphy@ti.com>
Cc: David Rivshin <drivshin@allworx.com>
Cc: Haojian Zhuang <haojian.zhuang@marvell.com>
Cc: H. Nikolaus Schaller <hns@goldelico.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Milo Kim <milo.kim@ti.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Nikita Travkin <nikitos.tr@gmail.com>
Cc: Orson Zhai <orsonzhai@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Philippe Retornaz <philippe.retornaz@epfl.ch>
Cc: Riku Voipio <riku.voipio@iki.fi>
Cc: Simon Guinot <sguinot@lacie.com>
Cc: Simon Shields <simon@lineageos.org>
Cc: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Cc: Xiaotong Lu <xiaotong.lu@spreadtrum.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>


# 54212f5a 03-Aug-2020 Pavel Machek <pavel@ucw.cz>

leds: add RGB color option, as that is different from multicolor.

Multicolor is a bit too abstract. Yes, we can have
Green-Magenta-Ultraviolet LED, but so far all the LEDs we support are
RGB, and not even RGB-White or RGB-Yellow variants emerged.

Multicolor is not a good fit for RGB LED. It does not really know
about LED color. In particular, there's no way to make LED "white".

Userspace is interested in knowing "this LED can produce arbitrary
color", which not all multicolor LEDs can.

Signed-off-by: Pavel Machek <pavel@ucw.cz>


# 92a81562 16-Jul-2020 Dan Murphy <dmurphy@ti.com>

leds: lp55xx: Add multicolor framework support to lp55xx

Add multicolor framework support for the lp55xx family.

Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>


# c732eaf0 16-Jul-2020 Dan Murphy <dmurphy@ti.com>

leds: lp55xx: Convert LED class registration to devm_*

Convert the LED class registration calls to the LED devm_*
registration calls.

Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>


# 7e6f7f3a 13-Jul-2020 Dan Murphy <dmurphy@ti.com>

leds: lp55xx: Fix file permissions to use DEVICE_ATTR macros

Fix the checkpatch warnings for the use of the file permission macros.
In converting the file permissions to the DEVICE_ATTR_XX macros the
call back function names needed to be updated within the code.

This means that the lp55xx_ needed to be dropped in the name to keep in
harmony with the ABI documentation.

Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
Signed-off-by: Pavel Machek <pavel@ucw.cz>


# ac219bf3 26-Jun-2020 Linus Walleij <linus.walleij@linaro.org>

leds: lp55xx: Convert to use GPIO descriptors

The LP55xx driver is already using the of_gpio() functions to
pick a global GPIO number for "enable" from the device tree and
request the line. Simplify it by just using a GPIO descriptor.

Make sure to keep the enable GPIO line optional, change the
naming from "lp5523_enable" to "LP55xx enable" to reflect that
this is used on all LP55xx LED drivers.

Cc: Milo Kim <milo.kim@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>


# d2912cb1 04-Jun-2019 Thomas Gleixner <tglx@linutronix.de>

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>


# 5ddb0869 11-Feb-2019 Michal Kazior <michal@plume.com>

leds: lp55xx: fix null deref on firmware load failure

I've stumbled upon a kernel crash and the logs
pointed me towards the lp5562 driver:

> <4>[306013.841294] lp5562 0-0030: Direct firmware load for lp5562 failed with error -2
> <4>[306013.894990] lp5562 0-0030: Falling back to user helper
> ...
> <3>[306073.924886] lp5562 0-0030: firmware request failed
> <1>[306073.939456] Unable to handle kernel NULL pointer dereference at virtual address 00000000
> <4>[306074.251011] PC is at _raw_spin_lock+0x1c/0x58
> <4>[306074.255539] LR is at release_firmware+0x6c/0x138
> ...

After taking a look I noticed firmware_release()
could be called with either NULL or a dangling
pointer.

Fixes: 10c06d178df11 ("leds-lp55xx: support firmware interface")
Signed-off-by: Michal Kazior <michal@plume.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>


# a86854d0 12-Jun-2018 Kees Cook <keescook@chromium.org>

treewide: devm_kzalloc() -> devm_kcalloc()

The devm_kzalloc() function has a 2-factor argument form, devm_kcalloc().
This patch replaces cases of:

devm_kzalloc(handle, a * b, gfp)

with:
devm_kcalloc(handle, a * b, gfp)

as well as handling cases of:

devm_kzalloc(handle, a * b * c, gfp)

with:

devm_kzalloc(handle, array3_size(a, b, c), gfp)

as it's slightly less ugly than:

devm_kcalloc(handle, array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

devm_kzalloc(handle, 4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

Some manual whitespace fixes were needed in this patch, as Coccinelle
really liked to write "=devm_kcalloc..." instead of "= devm_kcalloc...".

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
expression HANDLE;
type TYPE;
expression THING, E;
@@

(
devm_kzalloc(HANDLE,
- (sizeof(TYPE)) * E
+ sizeof(TYPE) * E
, ...)
|
devm_kzalloc(HANDLE,
- (sizeof(THING)) * E
+ sizeof(THING) * E
, ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression HANDLE;
expression COUNT;
typedef u8;
typedef __u8;
@@

(
devm_kzalloc(HANDLE,
- sizeof(u8) * (COUNT)
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(__u8) * (COUNT)
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(char) * (COUNT)
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(unsigned char) * (COUNT)
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(u8) * COUNT
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(__u8) * COUNT
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(char) * COUNT
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(unsigned char) * COUNT
+ COUNT
, ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
expression HANDLE;
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * (COUNT_ID)
+ COUNT_ID, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * COUNT_ID
+ COUNT_ID, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * (COUNT_CONST)
+ COUNT_CONST, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * COUNT_CONST
+ COUNT_CONST, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * (COUNT_ID)
+ COUNT_ID, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * COUNT_ID
+ COUNT_ID, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * (COUNT_CONST)
+ COUNT_CONST, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * COUNT_CONST
+ COUNT_CONST, sizeof(THING)
, ...)
)

// 2-factor product, only identifiers.
@@
expression HANDLE;
identifier SIZE, COUNT;
@@

- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- SIZE * COUNT
+ COUNT, SIZE
, ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression HANDLE;
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
devm_kzalloc(HANDLE,
- sizeof(TYPE) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression HANDLE;
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
devm_kzalloc(HANDLE,
- sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
expression HANDLE;
identifier STRIDE, SIZE, COUNT;
@@

(
devm_kzalloc(HANDLE,
- (COUNT) * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- COUNT * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- COUNT * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- (COUNT) * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- COUNT * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- (COUNT) * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- (COUNT) * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- COUNT * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression HANDLE;
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
devm_kzalloc(HANDLE,
- (E1) * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
|
devm_kzalloc(HANDLE,
- (E1) * (E2) * E3
+ array3_size(E1, E2, E3)
, ...)
|
devm_kzalloc(HANDLE,
- (E1) * (E2) * (E3)
+ array3_size(E1, E2, E3)
, ...)
|
devm_kzalloc(HANDLE,
- E1 * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression HANDLE;
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
devm_kzalloc(HANDLE, sizeof(THING) * C2, ...)
|
devm_kzalloc(HANDLE, sizeof(TYPE) * C2, ...)
|
devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
devm_kzalloc(HANDLE, C1 * C2, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * (E2)
+ E2, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * E2
+ E2, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * (E2)
+ E2, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * E2
+ E2, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- (E1) * E2
+ E1, E2
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- (E1) * (E2)
+ E1, E2
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- E1 * E2
+ E1, E2
, ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>


# 95b2af63 19-Aug-2015 Andrew Lunn <andrew@lunn.ch>

leds: lp55xx: 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: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: Milo Kim <milo.kim@ti.com>


# ed133352 24-Aug-2015 Milo Kim <milo.kim@ti.com>

leds:lp55xx: use the private data instead of updating I2C device platform data

Currently, lp55xx_of_populate_pdata() allocates lp55xx_platform_data if
it's null. And it parses the DT and copies values into the
'client->dev.platform_data'. This may have architectural issue.
Platform data is configurable through the DT or I2C board info inside the
platform area. However, lp55xx common driver changes this configuration
when it is loaded. So 'client->dev.platform_data' is not null anymore.
Eventually, the driver initialization is not identical when it's unloaded
and loaded again.
The lp55xx common driver should use the private data, 'lp55xx_chip->pdata'
instead of changing the original platform data.

So, lp55xx_of_populate_pdata() is modified as follows.
* Do not update 'dev->platform_data'. Return the pointer of new allocated
lp55xx_platform_data. Then the driver points it to private data,
'lp55xx_chip->pdata'.
* Each lp55xx driver checks the pointer and handles an error case.

Then, original platform data configuration will be kept regardless of
loading or unloading the driver.
The driver allocates the memory and copies them from the DT if it's NULL.
After the driver is loaded again, 'client->dev.platform_data' is same as
initial load, so the driver is initialized identically.

Cc: Toshi Kikuchi <toshik@chromium.org>
Cc: linux-leds@vger.kernel.org
Signed-off-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>


# b6789320 28-Jun-2015 Milo Kim <milo.kim@ti.com>

leds:lp55xx: fix firmware loading error

LP55xx driver uses not firmware file but raw data to load program through
the firmware interface.(Documents/leds/leds-lp55xx.txt)

For example, here is how to run blinking green channel pattern.
(The second engine is seleted and MUX is mapped to 'RGB' mode)
echo 2 > /sys/bus/i2c/devices/xxxx/select_engine
echo "RGB" > /sys/bus/i2c/devices/xxxx/engine_mux
echo 1 > /sys/class/firmware/lp5562/loading
echo "4000600040FF6000" > /sys/class/firmware/lp5562/data
echo 0 > /sys/class/firmware/lp5562/loading
echo 1 > /sys/bus/i2c/devices/xxxx/run_engine

However, '/sys/class/firmware/<device name>' is not created after the
firmware loader user helper was introduced.
This feature is used in the case below.

As soon as the firmware download is requested by the driver, firmware
class subsystem tries to find the binary file.
If it gets failed, then it just falls back to user helper to load
raw data manually. Here, you can see the device file under
/sys/class/firmware/.

To make it happen, LP55xx driver requires two configurations.

1. Enable CONFIG_FW_LOADER_USER_HELPER_FALLBACK in Kconfig
2. Set option, 'FW_OPT_USERHELPER' on requesting the firmware data.
It means the second option should be 'false' in
request_firmware_nowait().
This option enables to load firmware data manually by calling
fw_load_from_user_helper().

Cc: linux-leds@vger.kernel.org
Signed-off-by: Milo Kim <milo.kim@ti.com>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 44a1255b 25-Jun-2014 Johan Hovold <johan@kernel.org>

leds: lp55xx-common: fix attribute-creation race

Use the attribute groups of the led-class to create the LED attributes
during probe in order to avoid racing with userspace.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 660216bf 25-Jun-2014 Johan Hovold <johan@kernel.org>

leds: lp55xx-common: fix sysfs entry leak

Make sure the sysfs group is removed when the LEDs are unregistered.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 93ad8a1d 20-Nov-2013 Milo Kim <milo.kim@ti.com>

leds: lp5523: Support LED MUX configuration on running a pattern

There are two ways to run a pattern in LP5523.
One is using legacy sysfs files such as 'enginex_mode','enginex_load' and
'enginex_leds'. ('x' is from 1 to 3).
Among them, 'enginex_leds' are used for selecting specific LED channel MUX.
(MUX means which LEDs are used for running a pattern from LED 1 to 9.)

The other way is using the firmware interface.
In this mode, the default LED MUX strings are used.
In other words, LED MUX is not configurable on the fly.

This patch enables dynamic LED MUX configuration when the firmware is loaded.
By accessing the sysfs file 'enginex_leds', the LED channels can be configured.
To synchronize the operation mode, each engine mode should be set to 'LOAD'.

The documentation is updated as well.

Cc: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 30dae2f9 22-Oct-2013 Sebastian Reichel <sre@kernel.org>

leds: lp55xx: handle enable pin in driver

This patch moves the handling of the chip's enable pin from the board
code into the driver. It also updates all board-code files using the
driver to incorporate this change.

This is needed for device tree support of the enable pin.

Signed-off-by: Sebastian Reichel <sre@debian.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# f65f0a1a 15-Sep-2013 Linus Walleij <linus.walleij@linaro.org>

leds: lp55xx: enable setting default trigger

This enables setting a default trigger on an LP55xx channel,
either from platform data or device tree. This mechanism is
identical to the mechanism for GPIO LEDs and references the
common LEDs device tree bindings.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Milo Kim <milo.kim@ti.com>
Acked-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 33b3a561 09-Jul-2013 Kim, Milo <Milo.Kim@ti.com>

leds: support new LP8501 device - another LP55xx common

LP8501 can drive up to 9 channels like LP5523.
LEDs can be controlled directly via the I2C and programmable engines are
supported.

LP55xx common driver
LP8501 is one of LP55xx family device, so LP55xx common code are used.
Chip specific data is defined in the structure, 'lp55xx_device_config'.

Differences between LP8501 and LP5523
Different register layout for LED output control and others.
LP8501 specific feature for separate output power selection.
LP8501 doesn't support external clock detection.
Different programming engine data.

LP8501 specific feature - output power selection
Output channels are selected by power selection - Vout or Vdd.
Separate power for VDD1-6 and VDD7-9 are available.
It is configurable in the platform data.
To support this feature, LP55xx DT structure and header are changed.
Device tree binding is updated as well.

LED pattern data
Example pattern data is updated in the driver documentation.

Signed-off-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 2dac9128 07-May-2013 Kim, Milo <Milo.Kim@ti.com>

leds: lp55xx: support dynamic channel settings in the device tree structure

Currently, the LP55xx DT structure supports max 3 channels.
However, LP5523 has max 9 channels and LP5562 has 4 channels.
To enhance this constraint, the DT structure has been changed.

(a) Use the child node for various channel settings instead of fixed array
(b) Remove 'num_channel' property.
This value can be retrieved by counting the children node.
(c) 'chan-name' property supported
(d) Documentation updates for LP5521 and LP5523

(cooloney@gmail.com: fix a coding style issue in leds-lp55xx.txt)

Cc: Gabriel Fernandez <gabriel.fernandez@stericsson.com>
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 7542a04b 23-Apr-2013 Linus Walleij <linus.walleij@linaro.org>

leds: lp55xx: add support for Device Tree bindings

This patch allows the lp5521 driver to be successfully probed and
initialised when Device Tree support is enabled.

Based on a patch by Gabriel Fernandez, rewritten in accordance
with review feedback.

Cc: Gabriel Fernandez <gabriel.fernandez@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Milo Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 53b41922 20-Mar-2013 Kim, Milo <Milo.Kim@ti.com>

leds: lp55xx: use common clock framework when external clock is used

Program execution is timed with 32768Hz clock in the LP55xx family devices.
To run LED functionalities, LP55xx devices provide two options.
One is using internal clock. The other is using external clock.
This patch enables external clock detection automatically.
If external clock is not detected, then the internal clock will be used in the
LP55xx driver.

Valid clock rate is 32768Hz in LP55xx devices.

This new API is used in each LP55xx driver like LP5521 and LP5562.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 24d32128 14-Mar-2013 Kim, Milo <Milo.Kim@ti.com>

leds: lp55xx: fix the sysfs read operation

According to a sysfs documentation(Documentation/filesystem/sysfs.txt),
scnprintf() should be used in a read operation method.
It guarantees safe buffer size(PAGE_SIZE) which is allocated by the sysfs.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# ff45262a 18-Feb-2013 Kim, Milo <Milo.Kim@ti.com>

leds: add new LP5562 LED driver

LP5562 can drive up to 4 channels, RGB and White.
LEDs can be controlled directly via the led class control interface.

LP55xx common driver
LP5562 is one of LP55xx family device, so LP55xx common code are used.
On the other hand, chip specific configuration is defined in the structure
'lp55xx_device_config'

LED pattern data
LP5562 has also internal program memory which is used for running various LED
patterns. LP5562 driver supports the firmware interface and the predefined
pattern data as well.

LP5562 device attributes: 'led_pattern' and 'engine_mux'
A 'led_pattern' is an index code which runs the predefined pattern data.
And 'engine_mux' is updated with the firmware interface is activated.
Detailed description has been updated in the documentation files,
'leds-lp55xx.txt' and 'leds-lp5562.txt'.

Changes on the header file
LP5562 configurable definitions are added.
Pattern RGB data is fixed as constant value.
(No side effect on other devices, LP5521 or LP5523.)

(cooloney@gmail.com: remove redundant mutex_unlock(). Reported by Dan
Carpenter <dan.carpenter@oracle.com>)

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 109b8330 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: fix problem on removing LED attributes

LP55XX common device attributes, 'led_current' and 'max_current' are created
while loading the driver.
Those are LED device attributes which are removed automatically on releasing
led class devices - led_classdev_unregister().
Therefore, this duplicate code should be removed.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# ba6fa846 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: add new function for removing device attribtues

lp55xx_unregister_sysfs() is used for removing lp55xx device attributes.
Chip specific and engine attributes are removed on unloading the driver.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 240085e2 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: support device specific attributes

To support device specific attributes, new common driver function is added.
Eventually those are created on registering the sysfs with common dev attrs.
Furthermore, this patch makes adding device attributes simple in each driver.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 10c06d17 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: support firmware interface

This patch provides additional device attributes which enable
loading the firmware. ('select_engine' and 'run_engine')
To run a LED pattern, two parts of driver should be enabled.

Common features : lp55xx-common
===============================
Firmware interface for loading LED patterns

Chip specific features : leds-lp5521, leds-lp5523
=================================================
Register addresses for loading firmware data
Register addresses for running selected engine

Pattern programming sequence
============================
LP55xx chips have three program engines.
To load and run a LED pattern, the programming sequence is as follows.
(1) Select an engine number (1/2/3)
(2) Set engine mode to load
(3) Write pattern data into selected area
(4) Set engine mode to run

This sequence is almost same as the firmware interface.
(1) Select an engine number : 'select_engine' dev attribute
(2) Mode change to load : 'loading' of firmware class
(3) Write pattern data into selected area : 'data' of firmware class
(4) Mode change to run : 'run_engine' dev attribute

(1) and (4) are device specific features which provide callback functions
(2) and (3) are common features.

For example,
echo 1 or 2 or 3 > /sys/bus/i2c/devices/xxxx/select_engine
echo 1 > /sys/class/firmware/lp5521/loading
echo "4000600040FF6000" > /sys/class/firmware/lp5521/data
echo 0 > /sys/class/firmware/lp5521/loading
echo 1 > /sys/bus/i2c/devices/xxxx/run_engine

As soon as 'loading' is set to 0, registered callback is called.
Inside the callback, the selected engine is loaded and memory is updated.
To run programmed pattern, 'run_engine' attribute should be enabled.

Device specific data structure
==============================
o Firmware callback
load selected engine and update program memory
o Run engine
change the engine mode
o 'engine_idx' and firmware data, 'fw'
Those are used in the driver internally with callback functions

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# b3b6f811 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: add new lp55xx_register_sysfs() for the firmware interface

LP55xx family chips have internal program memory which run various patterns.
Using this memory, LEDs continue on blinking/dimming without continuous I2C
commands. That means the I2C HOST can be entered into sleep once the memory
is updated.

An application can get hex data from a file and write them into
the program memory through the I2C. This is general firwmare interface.

This patch is the initial step for adding the firmware interface.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# d9067d28 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: fix error condition in lp55xx_register_leds()

Use lp55xx_unregister_leds() rather than duplicate code.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# c3a68ebf 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: use lp55xx_unregister_leds()

To unregister led class devices and sysfs attributes,
LP5521 and LP5523 have each driver function.
This patch makes both drivers simple using common driver function,
lp55xx_unregister_leds().

And some unused variables are removed.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# a96bfa13 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: provide common LED current setting

LED current is configurable via the sysfs.
Max current is a read-only attribute.
These attributes code can be shared in lp55xx common driver.

Device attributes: 'led_current' and 'max_current'
move to lp55xx common driver

Replaced functions:
show_max_current() => lp55xx_show_max_current()
show_current() => lp55xx_show_current()
store_current() => lp55xx_store_current()

LED setting function: set_led_current()
Current registers are device specific, so configurable function is added
in each driver.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# a6e4679a 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: use lp55xx_set_brightness()

lp5521_set_brightness() and lp5523_set_brightness() are replaced with
common function, lp55xx_set_brightness().
This function is invoked when the brightness of each LED channel is updated.
LP5521 and LP5523 have different register address for the brightness control,
so this work is done by chip specific brightness_work_fn().

lp5521/5523_led_brightness_work():
use lp55xx_led and lp55xx_chip data structure.
use lp55xx write function.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 0e202346 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: use lp55xx_init_led() common function

lp5521_init_led() and lp5523_init_led() are replaced with one common function,
lp55xx_init_led().
Max channels is configurable, so it's used in lp55xx_init_led().

'LP5523_LEDS' are changed to 'LP5523_MAX_LEDS'.

lp55xx_set_brightness, lp55xx_led_attributes: skeleton
Will be filled in next patches.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 9e9b3db1 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: use lp55xx common led registration function

LED class devices are registered in lp5521_register_leds() and
lp5523_register_leds().
Two separate functions are merged into consolidated lp55xx function,
lp55xx_register_leds().

Error handling fix:
Unregistering LEDS are handled in lp55xx_register_leds() when LED registration
failure occurs. So each driver error handler is changed to 'err_register_leds'

Chip dependency: 'brightness_work_fn' and 'set_led_current'
To make the structure abstract, both functions are configured in each driver.
Those functions should be done by each driver because register control is
chip-dependant work.

lp55xx_init_led: skeleton
Will be filled in next patch

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 6ce61762 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: use lp55xx common deinit function

Two separate de-init functions are merged into one common function.
And it is used in err_post_init of lp55xx_init_device().

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 22ebeb48 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: clean up init function

lp5521/5523_init_device() are replaced with lp55xx common function,
lp55xx_init_device().

Error handler in init_device:
deinit function are matched with 'err_post_init' section in
lp55xx_init_device().

Remove LP5523 engine intialization code:
Engine functionality is not mandatory but optional.
Moreover engine initialization is done internally with device reset command.
Therefore, this code is unnecessary.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# ffbdccdb 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: use lp55xx common init function - post int

LP5521/5523 chip configuration is replaced with lp55xx common function,
lp55xx_post_init_device().

Name change:
lp5521/5523_configure() to lp5521/5523_post_init_device()
These are called in init function.

Register access function
Argument type is changed from 'i2c_client' to 'lp55xx_chip'.
Use exported R/W functions of lp55xx common driver.

Temporary variables in lp5521/5523_init_device()
These functions will be removed but temporary variables are needed for
blocking build warnings - incompatible pointer.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# e3a700d8 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: use lp55xx common init function - detect

LP5521/5523 chip detection functions are replaced with lp55xx common function,
lp55xx_detect_device().
Chip dependent address and values are configurable in each driver.
In init function, chip detection is executed.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# 48068d5d 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: use lp55xx common init function - reset

LP5521/5523 reset device functions are moved to lp55xx common driver.
Value of register address and value are chip dependent.
Those are configured in each driver.
In init function, reset command is executed.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# a85908dd 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: use lp55xx common init function - platform data

LP5521/5523 platform data functions are moved to lp55xx common driver.
New init function, lp55xx_init_device() is created.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>


# c93d08fa 05-Feb-2013 Milo(Woogyom) Kim <milo.kim@ti.com>

leds-lp55xx: add new common driver for lp5521/5523

This patch supports basic common driver code for LP5521, LP5523/55231 devices.

( Driver Structure Data )

lp55xx_led and lp55xx_chip
In lp55xx common driver, two different data structure is used.
o lp55xx_led
control multi output LED channels such as led current, channel index.
o lp55xx_chip
general chip control such like the I2C and platform data.

For example, LP5521 has maximum 3 LED channels.
LP5523/55231 has 9 output channels.

lp55xx_chip for LP5521 ... lp55xx_led #1
lp55xx_led #2
lp55xx_led #3

lp55xx_chip for LP5523 ... lp55xx_led #1
lp55xx_led #2
.
.
lp55xx_led #9

( Platform Data )

LP5521 and LP5523/55231 have own specific platform data.
However, this data can be handled with just one platform data structure.
The lp55xx platform data is declared in the header.
This structure is derived from leds-lp5521.h and leds-lp5523.h

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>