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authorMatt Campbell <mattrcampbell@gmail.com>2015-04-28 07:44:17 -0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-05-24 12:08:59 -0700
commitd9411e57dc7fcdbf28eb825d090b06b4248a95bc (patch)
treeecb950c779a3d706ae9679983e0fab66c911b5dd /Documentation/w1
parentf7134eea05b2fb4a2c0935f8a540539fff01f3eb (diff)
downloadlinux-sh-d9411e57dc7fcdbf28eb825d090b06b4248a95bc.tar.gz
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_therm11
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.