diff options
| author |   Robert Coulson <rob.coulson@gmail.com> | 2013-05-23 09:22:22 -0700 |
|---|---|---|
| committer |   Guenter Roeck <linux@roeck-us.net> | 2013-06-27 10:29:02 -0700 |
| commit | ed7c34e89d1e9d07f787a51571be0b96ae93d678 (patch) | |
| tree | 9ed1edda458a6aa57f23ab07e68c042fbb69b63b /Documentation/hwmon | |
| parent | hwmon: (ds1621) Add ds1631 chip support to ds1621 driver and documentation (diff) | |
| download | linux-dev-ed7c34e89d1e9d07f787a51571be0b96ae93d678.tar.xz linux-dev-ed7c34e89d1e9d07f787a51571be0b96ae93d678.zip | |
hwmon: (ds1621) Remove detect function
Due to a lack of device and vendor identification registers, the
Dallas/Maxim DS16xx devices cannot be uniquely detected, sometimes
resulting in false positives. Therefore, the detect function is
being removed in favor of explicit device instantiation.
Signed-off-by: Robert Coulson <rob.coulson@gmail.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'Documentation/hwmon')
| -rw-r--r-- | Documentation/hwmon/ds1621 | 25 |
1 files changed, 12 insertions, 13 deletions
diff --git a/Documentation/hwmon/ds1621 b/Documentation/hwmon/ds1621 index 1ebaa2485770..83780660f5b1 100644 --- a/Documentation/hwmon/ds1621 +++ b/Documentation/hwmon/ds1621 @@ -4,24 +4,22 @@ Kernel driver ds1621 Supported chips: * Dallas Semiconductor / Maxim Integrated DS1621 Prefix: 'ds1621' - Addresses scanned: I2C 0x48 - 0x4f + Addresses scanned: none Datasheet: Publicly available from www.maximintegrated.com * Dallas Semiconductor DS1625 - Prefix: - 'ds1621' - if binding via _detect function - 'ds1625' - explicit instantiation - Addresses scanned: I2C 0x48 - 0x4f + Prefix: 'ds1625' + Addresses scanned: none Datasheet: Publicly available from www.datasheetarchive.com * Maxim Integrated DS1631 Prefix: 'ds1631' - Addresses scanned: I2C 0x48 - 0x4f + Addresses scanned: none Datasheet: Publicly available from www.maximintegrated.com * Maxim Integrated DS1721 Prefix: 'ds1721' - Addresses scanned: I2C 0x48 - 0x4f + Addresses scanned: none Datasheet: Publicly available from www.maximintegrated.com Authors: @@ -77,12 +75,13 @@ The DS1625 is pin compatible and functionally equivalent with the DS1621, but the DS1621 is meant to replace it. The DS1631 and DS1721 are also pin compatible with the DS1621, but provide multi-resolution support. -Since there is no version register, there is no unique identification -for these devices. In addition, the DS1631 and DS1721 will emulate a -DS1621 device, if not explicitly instantiated (why? because the detect -function compares the temperature register values bits and checks for a -9-bit resolution). Therefore, for correct device identification and -functionality, explicit device instantiation is required. +Since there is no version or vendor identification register, there is +no unique identification for these devices. Therefore, explicit device +instantiation is required for correct device identification and functionality. + +And, for correct identification and operation, each device must be +explicitly instantiated, one device per address, in this address +range: 0x48..0x4f. The DS1721 is pin compatible with the DS1621, has an accuracy of +/- 1.0 degree Celsius over a -10 to +85 degree range, a minimum/maximum alarm |