0001 ========================
0002 Kernel driver w1_ds28e04
0003 ========================
0004
0005 Supported chips:
0006
0007 * Maxim DS28E04-100 4096-Bit Addressable 1-Wire EEPROM with PIO
0008
0009 supported family codes:
0010
0011 ================= ====
0012 W1_FAMILY_DS28E04 0x1C
0013 ================= ====
0014
0015 Author: Markus Franke, <franke.m@sebakmt.com> <franm@hrz.tu-chemnitz.de>
0016
0017 Description
0018 -----------
0019
0020 Support is provided through the sysfs files "eeprom" and "pio". CRC checking
0021 during memory accesses can optionally be enabled/disabled via the device
0022 attribute "crccheck". The strong pull-up can optionally be enabled/disabled
0023 via the module parameter "w1_strong_pullup".
0024
0025 Memory Access
0026
0027 A read operation on the "eeprom" file reads the given amount of bytes
0028 from the EEPROM of the DS28E04.
0029
0030 A write operation on the "eeprom" file writes the given byte sequence
0031 to the EEPROM of the DS28E04. If CRC checking mode is enabled only
0032 fully aligned blocks of 32 bytes with valid CRC16 values (in bytes 30
0033 and 31) are allowed to be written.
0034
0035 PIO Access
0036
0037 The 2 PIOs of the DS28E04-100 are accessible via the "pio" sysfs file.
0038
0039 The current status of the PIO's is returned as an 8 bit value. Bit 0/1
0040 represent the state of PIO_0/PIO_1. Bits 2..7 do not care. The PIO's are
0041 driven low-active, i.e. the driver delivers/expects low-active values.
