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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /Documentation/w1/slaves
Initial import
Diffstat (limited to 'Documentation/w1/slaves')
-rw-r--r--Documentation/w1/slaves/00-INDEX8
-rw-r--r--Documentation/w1/slaves/w1_ds240625
-rw-r--r--Documentation/w1/slaves/w1_ds242347
-rw-r--r--Documentation/w1/slaves/w1_ds28e0436
-rw-r--r--Documentation/w1/slaves/w1_therm50
5 files changed, 166 insertions, 0 deletions
diff --git a/Documentation/w1/slaves/00-INDEX b/Documentation/w1/slaves/00-INDEX
new file mode 100644
index 000000000..6e18c70c3
--- /dev/null
+++ b/Documentation/w1/slaves/00-INDEX
@@ -0,0 +1,8 @@
+00-INDEX
+ - This file
+w1_therm
+ - The Maxim/Dallas Semiconductor ds18*20 temperature sensor.
+w1_ds2423
+ - The Maxim/Dallas Semiconductor ds2423 counter device.
+w1_ds28e04
+ - The Maxim/Dallas Semiconductor ds28e04 eeprom.
diff --git a/Documentation/w1/slaves/w1_ds2406 b/Documentation/w1/slaves/w1_ds2406
new file mode 100644
index 000000000..8137fe6f6
--- /dev/null
+++ b/Documentation/w1/slaves/w1_ds2406
@@ -0,0 +1,25 @@
+w1_ds2406 kernel driver
+=======================
+
+Supported chips:
+ * Maxim DS2406 (and other family 0x12) addressable switches
+
+Author: Scott Alfter <scott@alfter.us>
+
+Description
+-----------
+
+The w1_ds2406 driver allows connected devices to be switched on and off.
+These chips also provide 128 bytes of OTP EPROM, but reading/writing it is
+not supported. In TSOC-6 form, the DS2406 provides two switch outputs and
+can be provided with power on a dedicated input. In TO-92 form, it provides
+one output and uses parasitic power only.
+
+The driver provides two sysfs files. state is readable; it gives the
+current state of each switch, with PIO A in bit 0 and PIO B in bit 1. The
+driver ORs this state with 0x30, so shell scripts get an ASCII 0/1/2/3 to
+work with. output is writable; bits 0 and 1 control PIO A and B,
+respectively. Bits 2-7 are ignored, so it's safe to write ASCII data.
+
+CRCs are checked on read and write. Failed checks cause an I/O error to be
+returned. On a failed write, the switch status is not changed.
diff --git a/Documentation/w1/slaves/w1_ds2423 b/Documentation/w1/slaves/w1_ds2423
new file mode 100644
index 000000000..3f98b505a
--- /dev/null
+++ b/Documentation/w1/slaves/w1_ds2423
@@ -0,0 +1,47 @@
+Kernel driver w1_ds2423
+=======================
+
+Supported chips:
+ * Maxim DS2423 based counter devices.
+
+supported family codes:
+ W1_THERM_DS2423 0x1D
+
+Author: Mika Laitio <lamikr@pilppa.org>
+
+Description
+-----------
+
+Support is provided through the sysfs w1_slave file. Each opening and
+read sequence of w1_slave file initiates the read of counters and ram
+available in DS2423 pages 12 - 15.
+
+Result of each page is provided as an ASCII output where each counter
+value and associated ram buffer is outpputed to own line.
+
+Each lines will contain the values of 42 bytes read from the counter and
+memory page along the crc=YES or NO for indicating whether the read operation
+was successful and CRC matched.
+If the operation was successful, there is also in the end of each line
+a counter value expressed as an integer after c=
+
+Meaning of 42 bytes represented is following:
+ - 1 byte from ram page
+ - 4 bytes for the counter value
+ - 4 zero bytes
+ - 2 bytes for crc16 which was calculated from the data read since the previous crc bytes
+ - 31 remaining bytes from the ram page
+ - crc=YES/NO indicating whether read was ok and crc matched
+ - c=<int> current counter value
+
+example from the successful read:
+00 02 00 00 00 00 00 00 00 6d 38 00 ff ff 00 00 fe ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=YES c=2
+00 02 00 00 00 00 00 00 00 e0 1f 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=YES c=2
+00 29 c6 5d 18 00 00 00 00 04 37 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=YES c=408798761
+00 05 00 00 00 00 00 00 00 8d 39 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff crc=YES c=5
+
+example from the read with crc errors:
+00 02 00 00 00 00 00 00 00 6d 38 00 ff ff 00 00 fe ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=YES c=2
+00 02 00 00 22 00 00 00 00 e0 1f 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=NO
+00 e1 61 5d 19 00 00 00 00 df 0b 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=NO
+00 05 00 00 20 00 00 00 00 8d 39 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff crc=NO
diff --git a/Documentation/w1/slaves/w1_ds28e04 b/Documentation/w1/slaves/w1_ds28e04
new file mode 100644
index 000000000..7819b65cf
--- /dev/null
+++ b/Documentation/w1/slaves/w1_ds28e04
@@ -0,0 +1,36 @@
+Kernel driver w1_ds28e04
+========================
+
+Supported chips:
+ * Maxim DS28E04-100 4096-Bit Addressable 1-Wire EEPROM with PIO
+
+supported family codes:
+ W1_FAMILY_DS28E04 0x1C
+
+Author: Markus Franke, <franke.m@sebakmt.com> <franm@hrz.tu-chemnitz.de>
+
+Description
+-----------
+
+Support is provided through the sysfs files "eeprom" and "pio". CRC checking
+during memory accesses can optionally be enabled/disabled via the device
+attribute "crccheck". The strong pull-up can optionally be enabled/disabled
+via the module parameter "w1_strong_pullup".
+
+Memory Access
+
+ A read operation on the "eeprom" file reads the given amount of bytes
+ from the EEPROM of the DS28E04.
+
+ A write operation on the "eeprom" file writes the given byte sequence
+ to the EEPROM of the DS28E04. If CRC checking mode is enabled only
+ fully aligned blocks of 32 bytes with valid CRC16 values (in bytes 30
+ and 31) are allowed to be written.
+
+PIO Access
+
+ The 2 PIOs of the DS28E04-100 are accessible via the "pio" sysfs file.
+
+ The current status of the PIO's is returned as an 8 bit value. Bit 0/1
+ represent the state of PIO_0/PIO_1. Bits 2..7 do not care. The PIO's are
+ driven low-active, i.e. the driver delivers/expects low-active values.
diff --git a/Documentation/w1/slaves/w1_therm b/Documentation/w1/slaves/w1_therm
new file mode 100644
index 000000000..cc62a95e4
--- /dev/null
+++ b/Documentation/w1/slaves/w1_therm
@@ -0,0 +1,50 @@
+Kernel driver w1_therm
+====================
+
+Supported chips:
+ * Maxim ds18*20 based temperature sensors.
+ * Maxim ds1825 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
+W1_THERM_DS1825 0x3B
+
+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=.
+
+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).
+
+The module parameter strong_pullup can be set to 0 to disable the
+strong pullup, 1 to enable autodetection or 2 to force strong pullup.
+In case of autodetection, the driver will use the "READ POWER SUPPLY"
+command to check if there are pariste powered devices on the bus.
+If so, it will activate the master's strong pullup.
+In case the detection of parasite devices using this command fails
+(seems to be the case with some DS18S20) the strong pullup can
+be force-enabled.
+If the strong pullup is enabled, the master's strong pullup will be
+driven when the conversion is taking place, provided the master driver
+does support the strong pullup (or it falls back to a pullup
+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.