From d9411e57dc7fcdbf28eb825d090b06b4248a95bc Mon Sep 17 00:00:00 2001 From: Matt Campbell Date: Tue, 28 Apr 2015 07:44:17 -0400 Subject: 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 Acked-by: Evgeniy Polyakov Signed-off-by: Greg Kroah-Hartman --- Documentation/w1/slaves/w1_therm | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'Documentation/w1') 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 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. -- cgit