0001 ========================
0002 Kernel driver for lp5523
0003 ========================
0004
0005 * National Semiconductor LP5523 led driver chip
0006 * Datasheet: http://www.national.com/pf/LP/LP5523.html
0007
0008 Authors: Mathias Nyman, Yuri Zaporozhets, Samu Onkalo
0009 Contact: Samu Onkalo (samu.p.onkalo-at-nokia.com)
0010
0011 Description
0012 -----------
0013 LP5523 can drive up to 9 channels. Leds can be controlled directly via
0014 the led class control interface.
0015 The name of each channel is configurable in the platform data - name and label.
0016 There are three options to make the channel name.
0017
0018 a) Define the 'name' in the platform data
0019
0020 To make specific channel name, then use 'name' platform data.
0021
0022 - /sys/class/leds/R1 (name: 'R1')
0023 - /sys/class/leds/B1 (name: 'B1')
0024
0025 b) Use the 'label' with no 'name' field
0026
0027 For one device name with channel number, then use 'label'.
0028 - /sys/class/leds/RGB:channelN (label: 'RGB', N: 0 ~ 8)
0029
0030 c) Default
0031
0032 If both fields are NULL, 'lp5523' is used by default.
0033 - /sys/class/leds/lp5523:channelN (N: 0 ~ 8)
0034
0035 LP5523 has the internal program memory for running various LED patterns.
0036 There are two ways to run LED patterns.
0037
0038 1) Legacy interface - enginex_mode, enginex_load and enginex_leds
0039
0040 Control interface for the engines:
0041
0042 x is 1 .. 3
0043
0044 enginex_mode:
0045 disabled, load, run
0046 enginex_load:
0047 microcode load
0048 enginex_leds:
0049 led mux control
0050
0051 ::
0052
0053 cd /sys/class/leds/lp5523:channel2/device
0054 echo "load" > engine3_mode
0055 echo "9d80400004ff05ff437f0000" > engine3_load
0056 echo "111111111" > engine3_leds
0057 echo "run" > engine3_mode
0058
0059 To stop the engine::
0060
0061 echo "disabled" > engine3_mode
0062
0063 2) Firmware interface - LP55xx common interface
0064
0065 For the details, please refer to 'firmware' section in leds-lp55xx.txt
0066
0067 LP5523 has three master faders. If a channel is mapped to one of
0068 the master faders, its output is dimmed based on the value of the master
0069 fader.
0070
0071 For example::
0072
0073 echo "123000123" > master_fader_leds
0074
0075 creates the following channel-fader mappings::
0076
0077 channel 0,6 to master_fader1
0078 channel 1,7 to master_fader2
0079 channel 2,8 to master_fader3
0080
0081 Then, to have 25% of the original output on channel 0,6::
0082
0083 echo 64 > master_fader1
0084
0085 To have 0% of the original output (i.e. no output) channel 1,7::
0086
0087 echo 0 > master_fader2
0088
0089 To have 100% of the original output (i.e. no dimming) on channel 2,8::
0090
0091 echo 255 > master_fader3
0092
0093 To clear all master fader controls::
0094
0095 echo "000000000" > master_fader_leds
0096
0097 Selftest uses always the current from the platform data.
0098
0099 Each channel contains led current settings.
0100 - /sys/class/leds/lp5523:channel2/led_current - RW
0101 - /sys/class/leds/lp5523:channel2/max_current - RO
0102
0103 Format: 10x mA i.e 10 means 1.0 mA
0104
0105 Example platform data::
0106
0107 static struct lp55xx_led_config lp5523_led_config[] = {
0108 {
0109 .name = "D1",
0110 .chan_nr = 0,
0111 .led_current = 50,
0112 .max_current = 130,
0113 },
0114 ...
0115 {
0116 .chan_nr = 8,
0117 .led_current = 50,
0118 .max_current = 130,
0119 }
0120 };
0121
0122 static int lp5523_setup(void)
0123 {
0124 /* Setup HW resources */
0125 }
0126
0127 static void lp5523_release(void)
0128 {
0129 /* Release HW resources */
0130 }
0131
0132 static void lp5523_enable(bool state)
0133 {
0134 /* Control chip enable signal */
0135 }
0136
0137 static struct lp55xx_platform_data lp5523_platform_data = {
0138 .led_config = lp5523_led_config,
0139 .num_channels = ARRAY_SIZE(lp5523_led_config),
0140 .clock_mode = LP55XX_CLOCK_EXT,
0141 .setup_resources = lp5523_setup,
0142 .release_resources = lp5523_release,
0143 .enable = lp5523_enable,
0144 };
0145
0146 Note
0147 chan_nr can have values between 0 and 8.
