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Documentation/input/cma3000_d0x.txt 2.78 KB
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b029ffafe   Hemanth V   Input: add CMA300... 
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  Kernel driver for CMA3000-D0x
  ============================
  
  Supported chips:
  * VTI CMA3000-D0x
  Datasheet:
    CMA3000-D0X Product Family Specification 8281000A.02.pdf
    <http://www.vti.fi/en/>
  
  Author: Hemanth V <hemanthv@ti.com>
  
  
  Description
  -----------
  CMA3000 Tri-axis accelerometer supports Motion detect, Measurement and
  Free fall modes.
  
  Motion Detect Mode: Its the low power mode where interrupts are generated only
  when motion exceeds the defined thresholds.
  
  Measurement Mode: This mode is used to read the acceleration data on X,Y,Z
  axis and supports 400, 100, 40 Hz sample frequency.
  
  Free fall Mode: This mode is intended to save system resources.
  
  Threshold values: Chip supports defining threshold values for above modes
  which includes time and g value. Refer product specifications for more details.
  
  CMA3000 chip supports mutually exclusive I2C and SPI interfaces for
  communication, currently the driver supports I2C based communication only.
  Initial configuration for bus mode is set in non volatile memory and can later
  be modified through bus interface command.
  
  Driver reports acceleration data through input subsystem. It generates ABS_MISC
  event with value 1 when free fall is detected.
  
  Platform data need to be configured for initial default values.
  
  Platform Data
  -------------
  fuzz_x: Noise on X Axis
  
  fuzz_y: Noise on Y Axis
  
  fuzz_z: Noise on Z Axis
  
  g_range: G range in milli g i.e 2000 or 8000
  
  mode: Default Operating mode
  
  mdthr: Motion detect g range threshold value
  
  mdfftmr: Motion detect and free fall time threshold value
  
  ffthr: Free fall g range threshold value
  
  Input Interface
  --------------
  Input driver version is 1.0.0
  Input device ID: bus 0x18 vendor 0x0 product 0x0 version 0x0
  Input device name: "cma3000-accelerometer"
  Supported events:
    Event type 0 (Sync)
    Event type 3 (Absolute)
      Event code 0 (X)
        Value     47
        Min    -8000
        Max     8000
        Fuzz     200
      Event code 1 (Y)
        Value    -28
        Min    -8000
        Max     8000
        Fuzz     200
      Event code 2 (Z)
        Value    905
        Min    -8000
        Max     8000
        Fuzz     200
      Event code 40 (Misc)
        Value      0
        Min        0
        Max        1
    Event type 4 (Misc)
  
  
  Register/Platform parameters Description
  ----------------------------------------
  
  mode:
  	0: power down mode
  	1: 100 Hz Measurement mode
  	2: 400 Hz Measurement mode
  	3: 40 Hz Measurement mode
  	4: Motion Detect mode (default)
  	5: 100 Hz Free fall mode
  	6: 40 Hz Free fall mode
  	7: Power off mode
  
  grange:
  	2000: 2000 mg or 2G Range
  	8000: 8000 mg or 8G Range
  
  mdthr:
  	X: X * 71mg (8G Range)
  	X: X * 18mg (2G Range)
  
  mdfftmr:
  	X: (X & 0x70) * 100 ms (MDTMR)
  	   (X & 0x0F) * 2.5 ms (FFTMR 400 Hz)
  	   (X & 0x0F) * 10 ms  (FFTMR 100 Hz)
  
  ffthr:
         X: (X >> 2) * 18mg (2G Range)
         X: (X & 0x0F) * 71 mg (8G Range)