| 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. |