diff options
| author | Matt Campbell <mattrcampbell@gmail.com> | 2015-04-28 07:44:17 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-05-24 12:08:59 -0700 |
| commit | d9411e57dc7fcdbf28eb825d090b06b4248a95bc (patch) | |
| tree | ecb950c779a3d706ae9679983e0fab66c911b5dd /Documentation/w1 | |
| parent | f7134eea05b2fb4a2c0935f8a540539fff01f3eb (diff) | |
| download | lwn-d9411e57dc7fcdbf28eb825d090b06b4248a95bc.tar.gz lwn-d9411e57dc7fcdbf28eb825d090b06b4248a95bc.zip | |
w1: Add support for DS28EA00 sequence to w1-therm
This patch provides support for the DS28EA00 digital thermometer.
The DS28EA00 provides an additional two pins for implementing a sequence
detection algorithm. This feature allows you to determine the physical
location of the chip in the 1-wire bus without needing pre-existing
knowledge of the bus ordering. Support is provided through the sysfs
w1_seq file. The file will contain a single line with an integer value
representing the device index in the bus starting at 0.
Signed-off-by: Matt Campbell <mattrcampbell@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/w1')
| -rw-r--r-- | Documentation/w1/slaves/w1_therm | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/Documentation/w1/slaves/w1_therm b/Documentation/w1/slaves/w1_therm index cc62a95e4776..13411fe52f7f 100644 --- a/Documentation/w1/slaves/w1_therm +++ b/Documentation/w1/slaves/w1_therm @@ -11,12 +11,14 @@ Author: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Description ----------- -w1_therm provides basic temperature conversion for ds18*20 devices. +w1_therm provides basic temperature conversion for ds18*20 devices, and the +ds28ea00 device. supported family codes: W1_THERM_DS18S20 0x10 W1_THERM_DS1822 0x22 W1_THERM_DS18B20 0x28 W1_THERM_DS1825 0x3B +W1_THERM_DS28EA00 0x42 Support is provided through the sysfs w1_slave file. Each open and read sequence will initiate a temperature conversion then provide two @@ -48,3 +50,10 @@ resistor). The DS18b20 temperature sensor specification lists a maximum current draw of 1.5mA and that a 5k pullup resistor is not sufficient. The strong pullup is designed to provide the additional current required. + +The DS28EA00 provides an additional two pins for implementing a sequence +detection algorithm. This feature allows you to determine the physical +location of the chip in the 1-wire bus without needing pre-existing +knowledge of the bus ordering. Support is provided through the sysfs +w1_seq file. The file will contain a single line with an integer value +representing the device index in the bus starting at 0. |