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