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1CMA3000-D0x Accelerometer2=========================3 4Supported chips:5* VTI CMA3000-D0x6 7Datasheet:8 CMA3000-D0X Product Family Specification 8281000A.02.pdf9 <http://www.vti.fi/en/>10 11:Author: Hemanth V <hemanthv@ti.com>12 13 14Description15-----------16 17CMA3000 Tri-axis accelerometer supports Motion detect, Measurement and18Free fall modes.19 20Motion Detect Mode:21 Its the low power mode where interrupts are generated only22 when motion exceeds the defined thresholds.23 24Measurement Mode:25 This mode is used to read the acceleration data on X,Y,Z26 axis and supports 400, 100, 40 Hz sample frequency.27 28Free fall Mode:29 This mode is intended to save system resources.30 31Threshold values:32 Chip supports defining threshold values for above modes33 which includes time and g value. Refer product specifications for34 more details.35 36CMA3000 chip supports mutually exclusive I2C and SPI interfaces for37communication, currently the driver supports I2C based communication only.38Initial configuration for bus mode is set in non volatile memory and can later39be modified through bus interface command.40 41Driver reports acceleration data through input subsystem. It generates ABS_MISC42event with value 1 when free fall is detected.43 44Platform data need to be configured for initial default values.45 46Platform Data47-------------48 49fuzz_x:50 Noise on X Axis51 52fuzz_y:53 Noise on Y Axis54 55fuzz_z:56 Noise on Z Axis57 58g_range:59 G range in milli g i.e 2000 or 800060 61mode:62 Default Operating mode63 64mdthr:65 Motion detect g range threshold value66 67mdfftmr:68 Motion detect and free fall time threshold value69 70ffthr:71 Free fall g range threshold value72 73Input Interface74---------------75 76Input driver version is 1.0.077Input device ID: bus 0x18 vendor 0x0 product 0x0 version 0x078Input device name: "cma3000-accelerometer"79 80Supported events::81 82 Event type 0 (Sync)83 Event type 3 (Absolute)84 Event code 0 (X)85 Value 4786 Min -800087 Max 800088 Fuzz 20089 Event code 1 (Y)90 Value -2891 Min -800092 Max 800093 Fuzz 20094 Event code 2 (Z)95 Value 90596 Min -800097 Max 800098 Fuzz 20099 Event code 40 (Misc)100 Value 0101 Min 0102 Max 1103 Event type 4 (Misc)104 105 106Register/Platform parameters Description107----------------------------------------108 109mode::110 111 0: power down mode112 1: 100 Hz Measurement mode113 2: 400 Hz Measurement mode114 3: 40 Hz Measurement mode115 4: Motion Detect mode (default)116 5: 100 Hz Free fall mode117 6: 40 Hz Free fall mode118 7: Power off mode119 120grange::121 122 2000: 2000 mg or 2G Range123 8000: 8000 mg or 8G Range124 125mdthr::126 127 X: X * 71mg (8G Range)128 X: X * 18mg (2G Range)129 130mdfftmr::131 132 X: (X & 0x70) * 100 ms (MDTMR)133 (X & 0x0F) * 2.5 ms (FFTMR 400 Hz)134 (X & 0x0F) * 10 ms (FFTMR 100 Hz)135 136ffthr::137 138 X: (X >> 2) * 18mg (2G Range)139 X: (X & 0x0F) * 71 mg (8G Range)140