1Kernel driver ads7828
2=====================
3
4Supported chips:
5  * Texas Instruments/Burr-Brown ADS7828
6    Prefix: 'ads7828'
7    Datasheet: Publicly available at the Texas Instruments website:
8               http://focus.ti.com/lit/ds/symlink/ads7828.pdf
9
10  * Texas Instruments ADS7830
11    Prefix: 'ads7830'
12    Datasheet: Publicly available at the Texas Instruments website:
13               http://focus.ti.com/lit/ds/symlink/ads7830.pdf
14
15Authors:
16        Steve Hardy <shardy@redhat.com>
17        Vivien Didelot <vivien.didelot@savoirfairelinux.com>
18        Guillaume Roguez <guillaume.roguez@savoirfairelinux.com>
19
20Platform data
21-------------
22
23The ads7828 driver accepts an optional ads7828_platform_data structure (defined
24in include/linux/platform_data/ads7828.h). The structure fields are:
25
26* diff_input: (bool) Differential operation
27  set to true for differential mode, false for default single ended mode.
28
29* ext_vref: (bool) External reference
30  set to true if it operates with an external reference, false for default
31  internal reference.
32
33* vref_mv: (unsigned int) Voltage reference
34  if using an external reference, set this to the reference voltage in mV,
35  otherwise it will default to the internal value (2500mV). This value will be
36  bounded with limits accepted by the chip, described in the datasheet.
37
38 If no structure is provided, the configuration defaults to single ended
39 operation and internal voltage reference (2.5V).
40
41Description
42-----------
43
44This driver implements support for the Texas Instruments ADS7828 and ADS7830.
45
46The ADS7828 device is a 12-bit 8-channel A/D converter, while the ADS7830 does
478-bit sampling.
48
49It can operate in single ended mode (8 +ve inputs) or in differential mode,
50where 4 differential pairs can be measured.
51
52The chip also has the facility to use an external voltage reference.  This
53may be required if your hardware supplies the ADS7828 from a 5V supply, see
54the datasheet for more details.
55
56There is no reliable way to identify this chip, so the driver will not scan
57some addresses to try to auto-detect it. That means that you will have to
58statically declare the device in the platform support code.
59