| Kernel driver ads7828 | |
| ===================== | |
| Supported chips: | |
| * Texas Instruments/Burr-Brown ADS7828 | |
| Prefix: 'ads7828' | |
| Datasheet: Publicly available at the Texas Instruments website: | |
| http://focus.ti.com/lit/ds/symlink/ads7828.pdf | |
| * Texas Instruments ADS7830 | |
| Prefix: 'ads7830' | |
| Datasheet: Publicly available at the Texas Instruments website: | |
| http://focus.ti.com/lit/ds/symlink/ads7830.pdf | |
| Authors: | |
| Steve Hardy <shardy@redhat.com> | |
| Vivien Didelot <vivien.didelot@savoirfairelinux.com> | |
| Guillaume Roguez <guillaume.roguez@savoirfairelinux.com> | |
| Platform data | |
| ------------- | |
| The ads7828 driver accepts an optional ads7828_platform_data structure (defined | |
| in include/linux/platform_data/ads7828.h). The structure fields are: | |
| * diff_input: (bool) Differential operation | |
| set to true for differential mode, false for default single ended mode. | |
| * ext_vref: (bool) External reference | |
| set to true if it operates with an external reference, false for default | |
| internal reference. | |
| * vref_mv: (unsigned int) Voltage reference | |
| if using an external reference, set this to the reference voltage in mV, | |
| otherwise it will default to the internal value (2500mV). This value will be | |
| bounded with limits accepted by the chip, described in the datasheet. | |
| If no structure is provided, the configuration defaults to single ended | |
| operation and internal voltage reference (2.5V). | |
| Description | |
| ----------- | |
| This driver implements support for the Texas Instruments ADS7828 and ADS7830. | |
| The ADS7828 device is a 12-bit 8-channel A/D converter, while the ADS7830 does | |
| 8-bit sampling. | |
| It can operate in single ended mode (8 +ve inputs) or in differential mode, | |
| where 4 differential pairs can be measured. | |
| The chip also has the facility to use an external voltage reference. This | |
| may be required if your hardware supplies the ADS7828 from a 5V supply, see | |
| the datasheet for more details. | |
| There is no reliable way to identify this chip, so the driver will not scan | |
| some addresses to try to auto-detect it. That means that you will have to | |
| statically declare the device in the platform support code. |