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Subject[PATCH 9/35] W1: create documentation for the w1_therm slave device
New directory for temperature sensor documentation.

Documentation/w1/00-INDEX 1.2
Added new subdirectory slaves

Documentation/w1/slaves/00-INDEX 1.1 1.2
Added index and w1_therm entry.

Documentation/w1/slaves/w1_therm 1.1 1.2
Initial entry for the temperature sensor.

Signed-off-by: David Fries <david@fries.net>
---
Documentation/w1/00-INDEX | 2 ++
Documentation/w1/slaves/00-INDEX | 4 ++++
Documentation/w1/slaves/w1_therm | 35 +++++++++++++++++++++++++++++++++++
3 files changed, 41 insertions(+), 0 deletions(-)

diff --git a/Documentation/w1/00-INDEX b/Documentation/w1/00-INDEX
index 5270cf4..cb49802 100644
--- a/Documentation/w1/00-INDEX
+++ b/Documentation/w1/00-INDEX
@@ -1,5 +1,7 @@
00-INDEX
- This file
+slaves/
+ - Drivers that provide support for specific family codes.
masters/
- Individual chips providing 1-wire busses.
w1.generic
diff --git a/Documentation/w1/slaves/00-INDEX b/Documentation/w1/slaves/00-INDEX
new file mode 100644
index 0000000..f8101d6
--- /dev/null
+++ b/Documentation/w1/slaves/00-INDEX
@@ -0,0 +1,4 @@
+00-INDEX
+ - This file
+w1_therm
+ - The Maxim/Dallas Semiconductor ds18*20 temperature sensor.
diff --git a/Documentation/w1/slaves/w1_therm b/Documentation/w1/slaves/w1_therm
new file mode 100644
index 0000000..7b045ae
--- /dev/null
+++ b/Documentation/w1/slaves/w1_therm
@@ -0,0 +1,35 @@
+Kernel driver w1_therm
+====================
+
+Supported chips:
+ * Maxim ds18*20 based temperature sensors.
+
+Author: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
+
+
+Description
+-----------
+
+w1_therm provides basic temperature conversion for ds18*20 devices.
+supported family codes:
+W1_THERM_DS18S20 0x10
+W1_THERM_DS1822 0x22
+W1_THERM_DS18B20 0x28
+Support is provided through the sysfs w1_slave file. Each open and
+read sequence will initiate a temperature conversion then provide two
+lines of ASCII output. The first line contains the nine hex bytes
+read along with a calculated crc value and YES or NO if it matched.
+If the crc matched the returned values are retained. The second line
+displays the retained values along with a temperature in millidegrees
+Centigrade after t=.
+
+w1_therm selects the current slave device for temperature conversion
+and provides a strong pullup if the master devices supports one and
+delays 750ms for the conversion.
+
+Parasite powered devices are limited to one slave performing a
+temperature conversion at a time. If none of the devices are parasite
+powered it would be possible to convert all the devices at the same
+time and then go back to read individual sensors. That isn't
+currently supported. The driver also doesn't support reduced
+precision (which would also reduce the conversion time).
--
1.4.4.4[unhandled content-type:application/pgp-signature]
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