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