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+========================
+Kernel driver for lm3556
+========================
+
+* Texas Instrument:
+  1.5 A Synchronous Boost LED Flash Driver w/ High-Side Current Source
+* Datasheet: http://www.national.com/ds/LM/LM3556.pdf
+
+Authors:
+      - Daniel Jeong
+
+        Contact:Daniel Jeong(daniel.jeong-at-ti.com, gshark.jeong-at-gmail.com)
+
+Description
+-----------
+There are 3 functions in LM3556, Flash, Torch and Indicator.
+
+Flash Mode
+^^^^^^^^^^
+
+In Flash Mode, the LED current source(LED) provides 16 target current levels
+from 93.75 mA to 1500 mA.The Flash currents are adjusted via the CURRENT
+CONTROL REGISTER(0x09).Flash mode is activated by the ENABLE REGISTER(0x0A),
+or by pulling the STROBE pin HIGH.
+
+LM3556 Flash can be controlled through sys/class/leds/flash/brightness file
+
+* if STROBE pin is enabled, below example control brightness only, and
+  ON / OFF will be controlled by STROBE pin.
+
+Flash Example:
+
+OFF::
+
+        #echo 0 > sys/class/leds/flash/brightness
+
+93.75 mA::
+
+        #echo 1 > sys/class/leds/flash/brightness
+
+...
+
+1500  mA::
+
+        #echo 16 > sys/class/leds/flash/brightness
+
+Torch Mode
+^^^^^^^^^^
+
+In Torch Mode, the current source(LED) is programmed via the CURRENT CONTROL
+REGISTER(0x09).Torch Mode is activated by the ENABLE REGISTER(0x0A) or by the
+hardware TORCH input.
+
+LM3556 torch can be controlled through sys/class/leds/torch/brightness file.
+* if TORCH pin is enabled, below example control brightness only,
+and ON / OFF will be controlled by TORCH pin.
+
+Torch Example:
+
+OFF::
+
+        #echo 0 > sys/class/leds/torch/brightness
+
+46.88 mA::
+
+        #echo 1 > sys/class/leds/torch/brightness
+
+...
+
+375 mA::
+
+        #echo 8 > sys/class/leds/torch/brightness
+
+Indicator Mode
+^^^^^^^^^^^^^^
+
+Indicator pattern can be set through sys/class/leds/indicator/pattern file,
+and 4 patterns are pre-defined in indicator_pattern array.
+
+According to N-lank, Pulse time and N Period values, different pattern wiill
+be generated.If you want new patterns for your own device, change
+indicator_pattern array with your own values and INDIC_PATTERN_SIZE.
+
+Please refer datasheet for more detail about N-Blank, Pulse time and N Period.
+
+Indicator pattern example:
+
+pattern 0::
+
+        #echo 0 > sys/class/leds/indicator/pattern
+
+...
+
+pattern 3::
+
+        #echo 3 > sys/class/leds/indicator/pattern
+
+Indicator brightness can be controlled through
+sys/class/leds/indicator/brightness file.
+
+Example:
+
+OFF::
+
+        #echo 0 > sys/class/leds/indicator/brightness
+
+5.86 mA::
+
+        #echo 1 > sys/class/leds/indicator/brightness
+
+...
+
+46.875mA::
+
+        #echo 8 > sys/class/leds/indicator/brightness
+
+Notes
+-----
+Driver expects it is registered using the i2c_board_info mechanism.
+To register the chip at address 0x63 on specific adapter, set the platform data
+according to include/linux/platform_data/leds-lm3556.h, set the i2c board info
+
+Example::
+
+        static struct i2c_board_info board_i2c_ch4[] __initdata = {
+                {
+                         I2C_BOARD_INFO(LM3556_NAME, 0x63),
+                         .platform_data = &lm3556_pdata,
+                 },
+        };
+
+and register it in the platform init function
+
+Example::
+
+        board_register_i2c_bus(4, 400,
+                                board_i2c_ch4, ARRAY_SIZE(board_i2c_ch4));