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+========================
+Kernel driver for lp5562
+========================
+
+* TI LP5562 LED Driver
+
+Author: Milo(Woogyom) Kim <milo.kim@ti.com>
+
+Description
+===========
+
+ LP5562 can drive up to 4 channels. R/G/B and White.
+ LEDs can be controlled directly via the led class control interface.
+
+ All four channels can be also controlled using the engine micro programs.
+ LP5562 has the internal program memory for running various LED patterns.
+ For the details, please refer to 'firmware' section in leds-lp55xx.txt
+
+Device attribute
+================
+
+engine_mux
+ 3 Engines are allocated in LP5562, but the number of channel is 4.
+ Therefore each channel should be mapped to the engine number.
+
+ Value: RGB or W
+
+ This attribute is used for programming LED data with the firmware interface.
+ Unlike the LP5521/LP5523/55231, LP5562 has unique feature for the engine mux,
+ so additional sysfs is required
+
+ LED Map
+
+ ===== === ===============================
+ Red ... Engine 1 (fixed)
+ Green ... Engine 2 (fixed)
+ Blue ... Engine 3 (fixed)
+ White ... Engine 1 or 2 or 3 (selective)
+ ===== === ===============================
+
+How to load the program data using engine_mux
+=============================================
+
+ Before loading the LP5562 program data, engine_mux should be written between
+ the engine selection and loading the firmware.
+ Engine mux has two different mode, RGB and W.
+ RGB is used for loading RGB program data, W is used for W program data.
+
+ For example, run blinking green channel pattern::
+
+ echo 2 > /sys/bus/i2c/devices/xxxx/select_engine # 2 is for green channel
+ echo "RGB" > /sys/bus/i2c/devices/xxxx/engine_mux # engine mux for RGB
+ echo 1 > /sys/class/firmware/lp5562/loading
+ echo "4000600040FF6000" > /sys/class/firmware/lp5562/data
+ echo 0 > /sys/class/firmware/lp5562/loading
+ echo 1 > /sys/bus/i2c/devices/xxxx/run_engine
+
+ To run a blinking white pattern::
+
+ echo 1 or 2 or 3 > /sys/bus/i2c/devices/xxxx/select_engine
+ echo "W" > /sys/bus/i2c/devices/xxxx/engine_mux
+ echo 1 > /sys/class/firmware/lp5562/loading
+ echo "4000600040FF6000" > /sys/class/firmware/lp5562/data
+ echo 0 > /sys/class/firmware/lp5562/loading
+ echo 1 > /sys/bus/i2c/devices/xxxx/run_engine
+
+How to load the predefined patterns
+===================================
+
+ Please refer to 'leds-lp55xx.txt"
+
+Setting Current of Each Channel
+===============================
+
+ Like LP5521 and LP5523/55231, LP5562 provides LED current settings.
+ The 'led_current' and 'max_current' are used.
+
+Example of Platform data
+========================
+
+::
+
+ static struct lp55xx_led_config lp5562_led_config[] = {
+ {
+ .name = "R",
+ .chan_nr = 0,
+ .led_current = 20,
+ .max_current = 40,
+ },
+ {
+ .name = "G",
+ .chan_nr = 1,
+ .led_current = 20,
+ .max_current = 40,
+ },
+ {
+ .name = "B",
+ .chan_nr = 2,
+ .led_current = 20,
+ .max_current = 40,
+ },
+ {
+ .name = "W",
+ .chan_nr = 3,
+ .led_current = 20,
+ .max_current = 40,
+ },
+ };
+
+ static int lp5562_setup(void)
+ {
+ /* setup HW resources */
+ }
+
+ static void lp5562_release(void)
+ {
+ /* Release HW resources */
+ }
+
+ static void lp5562_enable(bool state)
+ {
+ /* Control of chip enable signal */
+ }
+
+ static struct lp55xx_platform_data lp5562_platform_data = {
+ .led_config = lp5562_led_config,
+ .num_channels = ARRAY_SIZE(lp5562_led_config),
+ .setup_resources = lp5562_setup,
+ .release_resources = lp5562_release,
+ .enable = lp5562_enable,
+ };
+
+To configure the platform specific data, lp55xx_platform_data structure is used
+
+
+If the current is set to 0 in the platform data, that channel is
+disabled and it is not visible in the sysfs.