Documentation/hwmon/ads1015

   1 Kernel driver ads1015
   2 =====================
   3
   4 Supported 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   * Texas Instruments ADS1115
  10     Prefix: 'ads1115'
  11     Datasheet: Publicly available at the Texas Instruments website :
  12                http://focus.ti.com/lit/ds/symlink/ads1115.pdf
  13
  14 Authors:
  15         Dirk Eibach, Guntermann & Drunck GmbH <eibach@gdsys.de>
  16
  17 Description
  18 -----------
  19
  20 This driver implements support for the Texas Instruments ADS1015/ADS1115.
  21
  22 This device is a 12/16-bit A-D converter with 4 inputs.
  23
  24 The inputs can be used single ended or in certain differential combinations.
  25
  26 The inputs can be made available by 8 sysfs input files in0_input - in7_input:
  27 in0: Voltage over AIN0 and AIN1.
  28 in1: Voltage over AIN0 and AIN3.
  29 in2: Voltage over AIN1 and AIN3.
  30 in3: Voltage over AIN2 and AIN3.
  31 in4: Voltage over AIN0 and GND.
  32 in5: Voltage over AIN1 and GND.
  33 in6: Voltage over AIN2 and GND.
  34 in7: Voltage over AIN3 and GND.
  35
  36 Which inputs are available can be configured using platform data or devicetree.
  37
  38 By default all inputs are exported.
  39
  40 Platform Data
  41 -------------
  42
  43 In linux/i2c/ads1015.h platform data is defined, channel_data contains
  44 configuration data for the used input combinations:
  45 - pga is the programmable gain amplifier (values are full scale)
  46   0: +/- 6.144 V
  47   1: +/- 4.096 V
  48   2: +/- 2.048 V
  49   3: +/- 1.024 V
  50   4: +/- 0.512 V
  51   5: +/- 0.256 V
  52 - data_rate in samples per second
  53   0: 128
  54   1: 250
  55   2: 490
  56   3: 920
  57   4: 1600
  58   5: 2400
  59   6: 3300
  60
  61 Example:
  62 struct ads1015_platform_data data = {
  63         .channel_data = {
  64                 [2] = { .enabled = true, .pga = 1, .data_rate = 0 },
  65                 [4] = { .enabled = true, .pga = 4, .data_rate = 5 },
  66         }
  67 };
  68
  69 In this case only in2_input (FS +/- 4.096 V, 128 SPS) and in4_input
  70 (FS +/- 0.512 V, 2400 SPS) would be created.
  71
  72 Devicetree
  73 ----------
  74
  75 Configuration is also possible via devicetree:
  76 Documentation/devicetree/bindings/hwmon/ads1015.txt