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>

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>

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: 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>

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>

leds: lp55xx: add common macros for device attributes

This patch provides common macros for LP5521 and LP5523 device attributes and
functions.

(Device attributes)
LP5521: 'mode', 'load' and 'selftest'
LP5523: 'mode', 'load', 'leds' and 'selftest'

(Permissions)
mode: R/W
load: Write-only
leds: R/W
selftest: Read-only

Couple of lines are duplicate, so use these macros for adding device attributes
in LP5521 and LP5523 drivers.

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

leds: lp55xx: add common data structure for program

LP55xx family devices have internal three program engines which are used for
loading LED patterns. To maintain legacy device attributes, specific data
structure is used, 'mode' and 'led_mux'. The mode is used for showing/storing
current engine mode such like disabled, load and run. Then led_mux is used for
showing/storing current output LED selection.

This is only for LP5523/55231.

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

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>