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diff --git a/Documentation/hwmon/ads1015.rst b/Documentation/hwmon/ads1015.rst new file mode 100644 index 000000000000..e0951c4e57bb --- /dev/null +++ b/Documentation/hwmon/ads1015.rst @@ -0,0 +1,90 @@ +Kernel driver ads1015 +===================== + +Supported chips: + + * Texas Instruments ADS1015 + + Prefix: 'ads1015' + + Datasheet: Publicly available at the Texas Instruments website: + + http://focus.ti.com/lit/ds/symlink/ads1015.pdf + + * Texas Instruments ADS1115 + + Prefix: 'ads1115' + + Datasheet: Publicly available at the Texas Instruments website: + + http://focus.ti.com/lit/ds/symlink/ads1115.pdf + +Authors: + Dirk Eibach, Guntermann & Drunck GmbH <eibach@gdsys.de> + +Description +----------- + +This driver implements support for the Texas Instruments ADS1015/ADS1115. + +This device is a 12/16-bit A-D converter with 4 inputs. + +The inputs can be used single ended or in certain differential combinations. + +The inputs can be made available by 8 sysfs input files in0_input - in7_input: + + - in0: Voltage over AIN0 and AIN1. + - in1: Voltage over AIN0 and AIN3. + - in2: Voltage over AIN1 and AIN3. + - in3: Voltage over AIN2 and AIN3. + - in4: Voltage over AIN0 and GND. + - in5: Voltage over AIN1 and GND. + - in6: Voltage over AIN2 and GND. + - in7: Voltage over AIN3 and GND. + +Which inputs are available can be configured using platform data or devicetree. + +By default all inputs are exported. + +Platform Data +------------- + +In linux/platform_data/ads1015.h platform data is defined, channel_data contains +configuration data for the used input combinations: + +- pga is the programmable gain amplifier (values are full scale) + + - 0: +/- 6.144 V + - 1: +/- 4.096 V + - 2: +/- 2.048 V + - 3: +/- 1.024 V + - 4: +/- 0.512 V + - 5: +/- 0.256 V + +- data_rate in samples per second + + - 0: 128 + - 1: 250 + - 2: 490 + - 3: 920 + - 4: 1600 + - 5: 2400 + - 6: 3300 + +Example:: + + struct ads1015_platform_data data = { + .channel_data = { + [2] = { .enabled = true, .pga = 1, .data_rate = 0 }, + [4] = { .enabled = true, .pga = 4, .data_rate = 5 }, + } + }; + +In this case only in2_input (FS +/- 4.096 V, 128 SPS) and in4_input +(FS +/- 0.512 V, 2400 SPS) would be created. + +Devicetree +---------- + +Configuration is also possible via devicetree: +Documentation/devicetree/bindings/hwmon/ads1015.txt |