w1: Add 1-wire slave device driver for DS28E04-100

Signed-off-by: Markus Franke <franm@hrz.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 51 insertions, 0 deletions

diff --git a/Documentation/ABI/stable/sysfs-driver-w1_ds28e04 b/Documentation/ABI/stable/sysfs-driver-w1_ds28e04
new file mode 100644
index 000000000000..26579ee868c9
--- /dev/null
+++ b/Documentation/ABI/stable/sysfs-driver-w1_ds28e04
@@ -0,0 +1,15 @@
+What:           /sys/bus/w1/devices/.../pio
+Date:           May 2012
+Contact:        Markus Franke <franm@hrz.tu-chemnitz.de>
+Description:    read/write the contents of the two PIO's of the DS28E04-100
+                see Documentation/w1/slaves/w1_ds28e04 for detailed information
+Users:          any user space application which wants to communicate with DS28E04-100
+
+
+
+What:           /sys/bus/w1/devices/.../eeprom
+Date:           May 2012
+Contact:        Markus Franke <franm@hrz.tu-chemnitz.de>
+Description:    read/write the contents of the EEPROM memory of the DS28E04-100
+                see Documentation/w1/slaves/w1_ds28e04 for detailed information
+Users:          any user space application which wants to communicate with DS28E04-100
diff --git a/Documentation/w1/slaves/w1_ds28e04 b/Documentation/w1/slaves/w1_ds28e04
new file mode 100644
index 000000000000..85bc9a7e02fe
--- /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 alligned 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.