diff options
Diffstat (limited to 'Documentation/hwmon/ads7828')
-rw-r--r-- | Documentation/hwmon/ads7828 | 46 |
1 files changed, 34 insertions, 12 deletions
diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828 index 2bbebe6f771f..f6e263e0f607 100644 --- a/Documentation/hwmon/ads7828 +++ b/Documentation/hwmon/ads7828 | |||
@@ -4,29 +4,47 @@ Kernel driver ads7828 | |||
4 | Supported chips: | 4 | Supported chips: |
5 | * Texas Instruments/Burr-Brown ADS7828 | 5 | * Texas Instruments/Burr-Brown ADS7828 |
6 | Prefix: 'ads7828' | 6 | Prefix: 'ads7828' |
7 | Addresses scanned: I2C 0x48, 0x49, 0x4a, 0x4b | 7 | Datasheet: Publicly available at the Texas Instruments website: |
8 | Datasheet: Publicly available at the Texas Instruments website : | ||
9 | http://focus.ti.com/lit/ds/symlink/ads7828.pdf | 8 | http://focus.ti.com/lit/ds/symlink/ads7828.pdf |
10 | 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 | |||
11 | Authors: | 15 | Authors: |
12 | Steve Hardy <shardy@redhat.com> | 16 | Steve Hardy <shardy@redhat.com> |
17 | Vivien Didelot <vivien.didelot@savoirfairelinux.com> | ||
18 | Guillaume Roguez <guillaume.roguez@savoirfairelinux.com> | ||
19 | |||
20 | Platform data | ||
21 | ------------- | ||
22 | |||
23 | The ads7828 driver accepts an optional ads7828_platform_data structure (defined | ||
24 | in include/linux/platform_data/ads7828.h). The structure fields are: | ||
13 | 25 | ||
14 | Module Parameters | 26 | * diff_input: (bool) Differential operation |
15 | ----------------- | 27 | set to true for differential mode, false for default single ended mode. |
16 | 28 | ||
17 | * se_input: bool (default Y) | 29 | * ext_vref: (bool) External reference |
18 | Single ended operation - set to N for differential mode | 30 | set to true if it operates with an external reference, false for default |
19 | * int_vref: bool (default Y) | 31 | internal reference. |
20 | Operate with the internal 2.5V reference - set to N for external reference | 32 | |
21 | * vref_mv: int (default 2500) | 33 | * vref_mv: (unsigned int) Voltage reference |
22 | If using an external reference, set this to the reference voltage in mV | 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). | ||
23 | 40 | ||
24 | Description | 41 | Description |
25 | ----------- | 42 | ----------- |
26 | 43 | ||
27 | This driver implements support for the Texas Instruments ADS7828. | 44 | This driver implements support for the Texas Instruments ADS7828 and ADS7830. |
28 | 45 | ||
29 | This device is a 12-bit 8-channel A-D converter. | 46 | The ADS7828 device is a 12-bit 8-channel A/D converter, while the ADS7830 does |
47 | 8-bit sampling. | ||
30 | 48 | ||
31 | It can operate in single ended mode (8 +ve inputs) or in differential mode, | 49 | It can operate in single ended mode (8 +ve inputs) or in differential mode, |
32 | where 4 differential pairs can be measured. | 50 | where 4 differential pairs can be measured. |
@@ -34,3 +52,7 @@ where 4 differential pairs can be measured. | |||
34 | The chip also has the facility to use an external voltage reference. This | 52 | The chip also has the facility to use an external voltage reference. This |
35 | may be required if your hardware supplies the ADS7828 from a 5V supply, see | 53 | may be required if your hardware supplies the ADS7828 from a 5V supply, see |
36 | the datasheet for more details. | 54 | the datasheet for more details. |
55 | |||
56 | There is no reliable way to identify this chip, so the driver will not scan | ||
57 | some addresses to try to auto-detect it. That means that you will have to | ||
58 | statically declare the device in the platform support code. | ||