1========================
  2Kernel driver for lp5523
  3========================
  4
  5* National Semiconductor LP5523 led driver chip
  6* Datasheet: http://www.national.com/pf/LP/LP5523.html
  7
  8Authors: Mathias Nyman, Yuri Zaporozhets, Samu Onkalo
  9Contact: Samu Onkalo (samu.p.onkalo-at-nokia.com)
 10
 11Description
 12-----------
 13LP5523 can drive up to 9 channels. Leds can be controlled directly via
 14the led class control interface.
 15The name of each channel is configurable in the platform data - name and label.
 16There are three options to make the channel name.
 17
 18a) Define the 'name' in the platform data
 19
 20To make specific channel name, then use 'name' platform data.
 21
 22- /sys/class/leds/R1               (name: 'R1')
 23- /sys/class/leds/B1               (name: 'B1')
 24
 25b) Use the 'label' with no 'name' field
 26
 27For one device name with channel number, then use 'label'.
 28- /sys/class/leds/RGB:channelN     (label: 'RGB', N: 0 ~ 8)
 29
 30c) Default
 31
 32If both fields are NULL, 'lp5523' is used by default.
 33- /sys/class/leds/lp5523:channelN  (N: 0 ~ 8)
 34
 35LP5523 has the internal program memory for running various LED patterns.
 36There are two ways to run LED patterns.
 37
 381) Legacy interface - enginex_mode, enginex_load and enginex_leds
 39
 40  Control interface for the engines:
 41
 42  x is 1 .. 3
 43
 44  enginex_mode:
 45	disabled, load, run
 46  enginex_load:
 47	microcode load
 48  enginex_leds:
 49	led mux control
 50
 51  ::
 52
 53	cd /sys/class/leds/lp5523:channel2/device
 54	echo "load" > engine3_mode
 55	echo "9d80400004ff05ff437f0000" > engine3_load
 56	echo "111111111" > engine3_leds
 57	echo "run" > engine3_mode
 58
 59  To stop the engine::
 60
 61	echo "disabled" > engine3_mode
 62
 632) Firmware interface - LP55xx common interface
 64
 65For the details, please refer to 'firmware' section in leds-lp55xx.txt
 66
 67LP5523 has three master faders. If a channel is mapped to one of
 68the master faders, its output is dimmed based on the value of the master
 69fader.
 70
 71For example::
 72
 73  echo "123000123" > master_fader_leds
 74
 75creates the following channel-fader mappings::
 76
 77  channel 0,6 to master_fader1
 78  channel 1,7 to master_fader2
 79  channel 2,8 to master_fader3
 80
 81Then, to have 25% of the original output on channel 0,6::
 82
 83  echo 64 > master_fader1
 84
 85To have 0% of the original output (i.e. no output) channel 1,7::
 86
 87  echo 0 > master_fader2
 88
 89To have 100% of the original output (i.e. no dimming) on channel 2,8::
 90
 91  echo 255 > master_fader3
 92
 93To clear all master fader controls::
 94
 95  echo "000000000" > master_fader_leds
 96
 97Selftest uses always the current from the platform data.
 98
 99Each channel contains led current settings.
100- /sys/class/leds/lp5523:channel2/led_current - RW
101- /sys/class/leds/lp5523:channel2/max_current - RO
102
103Format: 10x mA i.e 10 means 1.0 mA
104
105Example platform data::
106
107	static struct lp55xx_led_config lp5523_led_config[] = {
108		{
109			.name		= "D1",
110			.chan_nr        = 0,
111			.led_current    = 50,
112			.max_current    = 130,
113		},
114	...
115		{
116			.chan_nr        = 8,
117			.led_current    = 50,
118			.max_current    = 130,
119		}
120	};
121
122	static int lp5523_setup(void)
123	{
124		/* Setup HW resources */
125	}
126
127	static void lp5523_release(void)
128	{
129		/* Release HW resources */
130	}
131
132	static void lp5523_enable(bool state)
133	{
134		/* Control chip enable signal */
135	}
136
137	static struct lp55xx_platform_data lp5523_platform_data = {
138		.led_config     = lp5523_led_config,
139		.num_channels   = ARRAY_SIZE(lp5523_led_config),
140		.clock_mode     = LP55XX_CLOCK_EXT,
141		.setup_resources   = lp5523_setup,
142		.release_resources = lp5523_release,
143		.enable            = lp5523_enable,
144	};
145
146Note
147  chan_nr can have values between 0 and 8.