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1Kernel driver ads1015
2=====================
3
4Supported chips:
5  * Texas Instruments ADS1015
6    Prefix: 'ads1015'
7    Datasheet: Publicly available at the Texas Instruments website :
8               http://focus.ti.com/lit/ds/symlink/ads1015.pdf
9
10Authors:
11        Dirk Eibach, Guntermann & Drunck GmbH <eibach@gdsys.de>
12
13Description
14-----------
15
16This driver implements support for the Texas Instruments ADS1015.
17
18This device is a 12-bit A-D converter with 4 inputs.
19
20The inputs can be used single ended or in certain differential combinations.
21
22The inputs can be made available by 8 sysfs input files in0_input - in7_input:
23in0: Voltage over AIN0 and AIN1.
24in1: Voltage over AIN0 and AIN3.
25in2: Voltage over AIN1 and AIN3.
26in3: Voltage over AIN2 and AIN3.
27in4: Voltage over AIN0 and GND.
28in5: Voltage over AIN1 and GND.
29in6: Voltage over AIN2 and GND.
30in7: Voltage over AIN3 and GND.
31
32Which inputs are available can be configured using platform data or devicetree.
33
34By default all inputs are exported.
35
36Platform Data
37-------------
38
39In linux/i2c/ads1015.h platform data is defined, channel_data contains
40configuration data for the used input combinations:
41- pga is the programmable gain amplifier (values are full scale)
42  0: +/- 6.144 V
43  1: +/- 4.096 V
44  2: +/- 2.048 V
45  3: +/- 1.024 V
46  4: +/- 0.512 V
47  5: +/- 0.256 V
48- data_rate in samples per second
49  0: 128
50  1: 250
51  2: 490
52  3: 920
53  4: 1600
54  5: 2400
55  6: 3300
56
57Example:
58struct ads1015_platform_data data = {
59	.channel_data = {
60		[2] = { .enabled = true, .pga = 1, .data_rate = 0 },
61		[4] = { .enabled = true, .pga = 4, .data_rate = 5 },
62	}
63};
64
65In this case only in2_input (FS +/- 4.096 V, 128 SPS) and in4_input
66(FS +/- 0.512 V, 2400 SPS) would be created.
67
68Devicetree
69----------
70
71Configuration is also possible via devicetree:
72Documentation/devicetree/bindings/hwmon/ads1015.txt
73