Documentation/leds/leds-lp5562.rst

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Documentation/leds/leds-lp5562.rst
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========================
Kernel driver for lp5562
========================

* TI LP5562 LED Driver

Author: Milo(Woogyom) Kim <milo.kim@ti.com>

Description
===========

  LP5562 can drive up to 4 channels. R/G/B and White.
  LEDs can be controlled directly via the led class control interface.

  All four channels can be also controlled using the engine micro programs.
  LP5562 has the internal program memory for running various LED patterns.
  For the details, please refer to 'firmware' section in leds-lp55xx.txt

Device attribute
================

engine_mux
  3 Engines are allocated in LP5562, but the number of channel is 4.
  Therefore each channel should be mapped to the engine number.

  Value: RGB or W

  This attribute is used for programming LED data with the firmware interface.
  Unlike the LP5521/LP5523/55231, LP5562 has unique feature for the engine mux,
  so additional sysfs is required

  LED Map

  ===== === ===============================
  Red   ... Engine 1 (fixed)
  Green ... Engine 2 (fixed)
  Blue  ... Engine 3 (fixed)
  White ... Engine 1 or 2 or 3 (selective)
  ===== === ===============================

How to load the program data using engine_mux
=============================================

  Before loading the LP5562 program data, engine_mux should be written between
  the engine selection and loading the firmware.
  Engine mux has two different mode, RGB and W.
  RGB is used for loading RGB program data, W is used for W program data.

  For example, run blinking green channel pattern::

    echo 2 > /sys/bus/i2c/devices/xxxx/select_engine     # 2 is for green channel
    echo "RGB" > /sys/bus/i2c/devices/xxxx/engine_mux    # engine mux for RGB
    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

  To run a blinking white pattern::

    echo 1 or 2 or 3 > /sys/bus/i2c/devices/xxxx/select_engine
    echo "W" > /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

How to load the predefined patterns
===================================

  Please refer to 'leds-lp55xx.txt"

Annotation

Implementation Notes