1========================
2Kernel driver for lp5562
3========================
4
5* TI LP5562 LED Driver
6
7Author: Milo(Woogyom) Kim <milo.kim@ti.com>
8
9Description
10===========
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.txt
18
19Device attribute
20================
21
22engine_mux
23  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 W
27
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 required
31
32  LED Map
33
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_mux
42=============================================
43
44  Before loading the LP5562 program data, engine_mux should be written between
45  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 channel
52    echo "RGB" > /sys/bus/i2c/devices/xxxx/engine_mux    # engine mux for RGB
53    echo 1 > /sys/class/firmware/lp5562/loading
54    echo "4000600040FF6000" > /sys/class/firmware/lp5562/data
55    echo 0 > /sys/class/firmware/lp5562/loading
56    echo 1 > /sys/bus/i2c/devices/xxxx/run_engine
57
58  To run a blinking white pattern::
59
60    echo 1 or 2 or 3 > /sys/bus/i2c/devices/xxxx/select_engine
61    echo "W" > /sys/bus/i2c/devices/xxxx/engine_mux
62    echo 1 > /sys/class/firmware/lp5562/loading
63    echo "4000600040FF6000" > /sys/class/firmware/lp5562/data
64    echo 0 > /sys/class/firmware/lp5562/loading
65    echo 1 > /sys/bus/i2c/devices/xxxx/run_engine
66
67How to load the predefined patterns
68===================================
69
70  Please refer to 'leds-lp55xx.txt"
71
72Setting Current of Each Channel
73===============================
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 data
79========================
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 used
134
135
136If the current is set to 0 in the platform data, that channel is
137disabled and it is not visible in the sysfs.
138