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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)
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