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Diffstat (limited to 'Documentation/leds/leds-lp55xx.txt')
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diff --git a/Documentation/leds/leds-lp55xx.txt b/Documentation/leds/leds-lp55xx.txt deleted file mode 100644 index e23fa91ea722..000000000000 --- a/Documentation/leds/leds-lp55xx.txt +++ /dev/null @@ -1,194 +0,0 @@ -LP5521/LP5523/LP55231/LP5562/LP8501 Common Driver -================================================= - -Authors: Milo(Woogyom) Kim <milo.kim@ti.com> - -Description ------------ -LP5521, LP5523/55231, LP5562 and LP8501 have common features as below. - - Register access via the I2C - Device initialization/deinitialization - Create LED class devices for multiple output channels - Device attributes for user-space interface - Program memory for running LED patterns - -The LP55xx common driver provides these features using exported functions. - lp55xx_init_device() / lp55xx_deinit_device() - lp55xx_register_leds() / lp55xx_unregister_leds() - lp55xx_regsister_sysfs() / lp55xx_unregister_sysfs() - -( Driver Structure Data ) - -In lp55xx common driver, two different data structure is used. - -o lp55xx_led - control multi output LED channels such as led current, channel index. -o lp55xx_chip - general chip control such like the I2C and platform data. - -For example, LP5521 has maximum 3 LED channels. -LP5523/55231 has 9 output channels. - -lp55xx_chip for LP5521 ... lp55xx_led #1 - lp55xx_led #2 - lp55xx_led #3 - -lp55xx_chip for LP5523 ... lp55xx_led #1 - lp55xx_led #2 - . - . - lp55xx_led #9 - -( Chip Dependent Code ) - -To support device specific configurations, special structure -'lpxx_device_config' is used. - - Maximum number of channels - Reset command, chip enable command - Chip specific initialization - Brightness control register access - Setting LED output current - Program memory address access for running patterns - Additional device specific attributes - -( Firmware Interface ) - -LP55xx family devices have the internal program memory for running -various LED patterns. -This pattern data is saved as a file in the user-land or -hex byte string is written into the memory through the I2C. -LP55xx common driver supports the firmware interface. - -LP55xx chips have three program engines. -To load and run the pattern, the programming sequence is following. - (1) Select an engine number (1/2/3) - (2) Mode change to load - (3) Write pattern data into selected area - (4) Mode change to run - -The LP55xx common driver provides simple interfaces as below. -select_engine : Select which engine is used for running program -run_engine : Start program which is loaded via the firmware interface -firmware : Load program data - -In case of LP5523, one more command is required, 'enginex_leds'. -It is used for selecting LED output(s) at each engine number. -In more details, please refer to 'leds-lp5523.txt'. - -For example, run blinking pattern in engine #1 of LP5521 -echo 1 > /sys/bus/i2c/devices/xxxx/select_engine -echo 1 > /sys/class/firmware/lp5521/loading -echo "4000600040FF6000" > /sys/class/firmware/lp5521/data -echo 0 > /sys/class/firmware/lp5521/loading -echo 1 > /sys/bus/i2c/devices/xxxx/run_engine - -For example, run blinking pattern in engine #3 of LP55231 -Two LEDs are configured as pattern output channels. -echo 3 > /sys/bus/i2c/devices/xxxx/select_engine -echo 1 > /sys/class/firmware/lp55231/loading -echo "9d0740ff7e0040007e00a0010000" > /sys/class/firmware/lp55231/data -echo 0 > /sys/class/firmware/lp55231/loading -echo "000001100" > /sys/bus/i2c/devices/xxxx/engine3_leds -echo 1 > /sys/bus/i2c/devices/xxxx/run_engine - -To start blinking patterns in engine #2 and #3 simultaneously, -for idx in 2 3 -do - echo $idx > /sys/class/leds/red/device/select_engine - sleep 0.1 - echo 1 > /sys/class/firmware/lp5521/loading - echo "4000600040FF6000" > /sys/class/firmware/lp5521/data - echo 0 > /sys/class/firmware/lp5521/loading -done -echo 1 > /sys/class/leds/red/device/run_engine - -Here is another example for LP5523. -Full LED strings are selected by 'engine2_leds'. -echo 2 > /sys/bus/i2c/devices/xxxx/select_engine -echo 1 > /sys/class/firmware/lp5523/loading -echo "9d80400004ff05ff437f0000" > /sys/class/firmware/lp5523/data -echo 0 > /sys/class/firmware/lp5523/loading -echo "111111111" > /sys/bus/i2c/devices/xxxx/engine2_leds -echo 1 > /sys/bus/i2c/devices/xxxx/run_engine - -As soon as 'loading' is set to 0, registered callback is called. -Inside the callback, the selected engine is loaded and memory is updated. -To run programmed pattern, 'run_engine' attribute should be enabled. - -The pattern sequence of LP8501 is similar to LP5523. -However pattern data is specific. -Ex 1) Engine 1 is used -echo 1 > /sys/bus/i2c/devices/xxxx/select_engine -echo 1 > /sys/class/firmware/lp8501/loading -echo "9d0140ff7e0040007e00a001c000" > /sys/class/firmware/lp8501/data -echo 0 > /sys/class/firmware/lp8501/loading -echo 1 > /sys/bus/i2c/devices/xxxx/run_engine - -Ex 2) Engine 2 and 3 are used at the same time -echo 2 > /sys/bus/i2c/devices/xxxx/select_engine -sleep 1 -echo 1 > /sys/class/firmware/lp8501/loading -echo "9d0140ff7e0040007e00a001c000" > /sys/class/firmware/lp8501/data -echo 0 > /sys/class/firmware/lp8501/loading -sleep 1 -echo 3 > /sys/bus/i2c/devices/xxxx/select_engine -sleep 1 -echo 1 > /sys/class/firmware/lp8501/loading -echo "9d0340ff7e0040007e00a001c000" > /sys/class/firmware/lp8501/data -echo 0 > /sys/class/firmware/lp8501/loading -sleep 1 -echo 1 > /sys/class/leds/d1/device/run_engine - -( 'run_engine' and 'firmware_cb' ) -The sequence of running the program data is common. -But each device has own specific register addresses for commands. -To support this, 'run_engine' and 'firmware_cb' are configurable in each driver. -run_engine : Control the selected engine -firmware_cb : The callback function after loading the firmware is done. - Chip specific commands for loading and updating program memory. - -( Predefined pattern data ) - -Without the firmware interface, LP55xx driver provides another method for -loading a LED pattern. That is 'predefined' pattern. -A predefined pattern is defined in the platform data and load it(or them) -via the sysfs if needed. -To use the predefined pattern concept, 'patterns' and 'num_patterns' should be -configured. - - Example of predefined pattern data: - - /* mode_1: blinking data */ - static const u8 mode_1[] = { - 0x40, 0x00, 0x60, 0x00, 0x40, 0xFF, 0x60, 0x00, - }; - - /* mode_2: always on */ - static const u8 mode_2[] = { 0x40, 0xFF, }; - - struct lp55xx_predef_pattern board_led_patterns[] = { - { - .r = mode_1, - .size_r = ARRAY_SIZE(mode_1), - }, - { - .b = mode_2, - .size_b = ARRAY_SIZE(mode_2), - }, - } - - struct lp55xx_platform_data lp5562_pdata = { - ... - .patterns = board_led_patterns, - .num_patterns = ARRAY_SIZE(board_led_patterns), - }; - -Then, mode_1 and mode_2 can be run via through the sysfs. - - echo 1 > /sys/bus/i2c/devices/xxxx/led_pattern # red blinking LED pattern - echo 2 > /sys/bus/i2c/devices/xxxx/led_pattern # blue LED always on - -To stop running pattern, - echo 0 > /sys/bus/i2c/devices/xxxx/led_pattern |