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1========================2Kernel driver for lp55623========================4 5* TI LP5562 LED Driver6 7Author: Milo(Woogyom) Kim <milo.kim@ti.com>8 9Description10===========11 12 LP5562 can drive up to 4 channels. R/G/B and White.13 LEDs can be controlled directly via the led class control interface.14 15 All four channels can be also controlled using the engine micro programs.16 LP5562 has the internal program memory for running various LED patterns.17 For the details, please refer to 'firmware' section in leds-lp55xx.txt18 19Device attribute20================21 22engine_mux23 3 Engines are allocated in LP5562, but the number of channel is 4.24 Therefore each channel should be mapped to the engine number.25 26 Value: RGB or W27 28 This attribute is used for programming LED data with the firmware interface.29 Unlike the LP5521/LP5523/55231, LP5562 has unique feature for the engine mux,30 so additional sysfs is required31 32 LED Map33 34 ===== === ===============================35 Red ... Engine 1 (fixed)36 Green ... Engine 2 (fixed)37 Blue ... Engine 3 (fixed)38 White ... Engine 1 or 2 or 3 (selective)39 ===== === ===============================40 41How to load the program data using engine_mux42=============================================43 44 Before loading the LP5562 program data, engine_mux should be written between45 the engine selection and loading the firmware.46 Engine mux has two different mode, RGB and W.47 RGB is used for loading RGB program data, W is used for W program data.48 49 For example, run blinking green channel pattern::50 51 echo 2 > /sys/bus/i2c/devices/xxxx/select_engine # 2 is for green channel52 echo "RGB" > /sys/bus/i2c/devices/xxxx/engine_mux # engine mux for RGB53 echo 1 > /sys/class/firmware/lp5562/loading54 echo "4000600040FF6000" > /sys/class/firmware/lp5562/data55 echo 0 > /sys/class/firmware/lp5562/loading56 echo 1 > /sys/bus/i2c/devices/xxxx/run_engine57 58 To run a blinking white pattern::59 60 echo 1 or 2 or 3 > /sys/bus/i2c/devices/xxxx/select_engine61 echo "W" > /sys/bus/i2c/devices/xxxx/engine_mux62 echo 1 > /sys/class/firmware/lp5562/loading63 echo "4000600040FF6000" > /sys/class/firmware/lp5562/data64 echo 0 > /sys/class/firmware/lp5562/loading65 echo 1 > /sys/bus/i2c/devices/xxxx/run_engine66 67How to load the predefined patterns68===================================69 70 Please refer to 'leds-lp55xx.txt"71 72Setting Current of Each Channel73===============================74 75 Like LP5521 and LP5523/55231, LP5562 provides LED current settings.76 The 'led_current' and 'max_current' are used.77 78Example of Platform data79========================80 81::82 83 static struct lp55xx_led_config lp5562_led_config[] = {84 {85 .name = "R",86 .chan_nr = 0,87 .led_current = 20,88 .max_current = 40,89 },90 {91 .name = "G",92 .chan_nr = 1,93 .led_current = 20,94 .max_current = 40,95 },96 {97 .name = "B",98 .chan_nr = 2,99 .led_current = 20,100 .max_current = 40,101 },102 {103 .name = "W",104 .chan_nr = 3,105 .led_current = 20,106 .max_current = 40,107 },108 };109 110 static int lp5562_setup(void)111 {112 /* setup HW resources */113 }114 115 static void lp5562_release(void)116 {117 /* Release HW resources */118 }119 120 static void lp5562_enable(bool state)121 {122 /* Control of chip enable signal */123 }124 125 static struct lp55xx_platform_data lp5562_platform_data = {126 .led_config = lp5562_led_config,127 .num_channels = ARRAY_SIZE(lp5562_led_config),128 .setup_resources = lp5562_setup,129 .release_resources = lp5562_release,130 .enable = lp5562_enable,131 };132 133To configure the platform specific data, lp55xx_platform_data structure is used134 135 136If the current is set to 0 in the platform data, that channel is137disabled and it is not visible in the sysfs.138