diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/input/cma3000_d0x.txt | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/Documentation/input/cma3000_d0x.txt b/Documentation/input/cma3000_d0x.txt new file mode 100644 index 000000000000..29d088db4afd --- /dev/null +++ b/Documentation/input/cma3000_d0x.txt | |||
@@ -0,0 +1,115 @@ | |||
1 | Kernel driver for CMA3000-D0x | ||
2 | ============================ | ||
3 | |||
4 | Supported chips: | ||
5 | * VTI CMA3000-D0x | ||
6 | Datasheet: | ||
7 | CMA3000-D0X Product Family Specification 8281000A.02.pdf | ||
8 | <http://www.vti.fi/en/> | ||
9 | |||
10 | Author: Hemanth V <hemanthv@ti.com> | ||
11 | |||
12 | |||
13 | Description | ||
14 | ----------- | ||
15 | CMA3000 Tri-axis accelerometer supports Motion detect, Measurement and | ||
16 | Free fall modes. | ||
17 | |||
18 | Motion Detect Mode: Its the low power mode where interrupts are generated only | ||
19 | when motion exceeds the defined thresholds. | ||
20 | |||
21 | Measurement Mode: This mode is used to read the acceleration data on X,Y,Z | ||
22 | axis and supports 400, 100, 40 Hz sample frequency. | ||
23 | |||
24 | Free fall Mode: This mode is intended to save system resources. | ||
25 | |||
26 | Threshold values: Chip supports defining threshold values for above modes | ||
27 | which includes time and g value. Refer product specifications for more details. | ||
28 | |||
29 | CMA3000 chip supports mutually exclusive I2C and SPI interfaces for | ||
30 | communication, currently the driver supports I2C based communication only. | ||
31 | Initial configuration for bus mode is set in non volatile memory and can later | ||
32 | be modified through bus interface command. | ||
33 | |||
34 | Driver reports acceleration data through input subsystem. It generates ABS_MISC | ||
35 | event with value 1 when free fall is detected. | ||
36 | |||
37 | Platform data need to be configured for initial default values. | ||
38 | |||
39 | Platform Data | ||
40 | ------------- | ||
41 | fuzz_x: Noise on X Axis | ||
42 | |||
43 | fuzz_y: Noise on Y Axis | ||
44 | |||
45 | fuzz_z: Noise on Z Axis | ||
46 | |||
47 | g_range: G range in milli g i.e 2000 or 8000 | ||
48 | |||
49 | mode: Default Operating mode | ||
50 | |||
51 | mdthr: Motion detect g range threshold value | ||
52 | |||
53 | mdfftmr: Motion detect and free fall time threshold value | ||
54 | |||
55 | ffthr: Free fall g range threshold value | ||
56 | |||
57 | Input Interface | ||
58 | -------------- | ||
59 | Input driver version is 1.0.0 | ||
60 | Input device ID: bus 0x18 vendor 0x0 product 0x0 version 0x0 | ||
61 | Input device name: "cma3000-accelerometer" | ||
62 | Supported events: | ||
63 | Event type 0 (Sync) | ||
64 | Event type 3 (Absolute) | ||
65 | Event code 0 (X) | ||
66 | Value 47 | ||
67 | Min -8000 | ||
68 | Max 8000 | ||
69 | Fuzz 200 | ||
70 | Event code 1 (Y) | ||
71 | Value -28 | ||
72 | Min -8000 | ||
73 | Max 8000 | ||
74 | Fuzz 200 | ||
75 | Event code 2 (Z) | ||
76 | Value 905 | ||
77 | Min -8000 | ||
78 | Max 8000 | ||
79 | Fuzz 200 | ||
80 | Event code 40 (Misc) | ||
81 | Value 0 | ||
82 | Min 0 | ||
83 | Max 1 | ||
84 | Event type 4 (Misc) | ||
85 | |||
86 | |||
87 | Register/Platform parameters Description | ||
88 | ---------------------------------------- | ||
89 | |||
90 | mode: | ||
91 | 0: power down mode | ||
92 | 1: 100 Hz Measurement mode | ||
93 | 2: 400 Hz Measurement mode | ||
94 | 3: 40 Hz Measurement mode | ||
95 | 4: Motion Detect mode (default) | ||
96 | 5: 100 Hz Free fall mode | ||
97 | 6: 40 Hz Free fall mode | ||
98 | 7: Power off mode | ||
99 | |||
100 | grange: | ||
101 | 2000: 2000 mg or 2G Range | ||
102 | 8000: 8000 mg or 8G Range | ||
103 | |||
104 | mdthr: | ||
105 | X: X * 71mg (8G Range) | ||
106 | X: X * 18mg (2G Range) | ||
107 | |||
108 | mdfftmr: | ||
109 | X: (X & 0x70) * 100 ms (MDTMR) | ||
110 | (X & 0x0F) * 2.5 ms (FFTMR 400 Hz) | ||
111 | (X & 0x0F) * 10 ms (FFTMR 100 Hz) | ||
112 | |||
113 | ffthr: | ||
114 | X: (X >> 2) * 18mg (2G Range) | ||
115 | X: (X & 0x0F) * 71 mg (8G Range) | ||