Kernel driver `mic74.o' ========================= Status: Beta Supported chips: * Micrel MIC74 Prefix: 'mic74' Addresses scanned: I2C 0x20 - 0x27 Datasheet: Publicly available at the Micrel website http://www.micrel.com/ Authors: zebo25 mds (cleanups and this doc) Module Parameters ----------------- Description ----------- The MIC74 is an 8-bit I/O expander for the I2C bus. Semiconductors. It is designed to provide a byte I2C interface to up to 8 separate devices. This device consists of a quasi-bidirectionnal port. Each of the eight I/Os can be independently used as an input or output. The driver does not initialize the ports, they will be at their power-up defaults, or however the BIOS programmed them. For more information see the datasheet. Accessing MIC74 via /proc interface ------------------------------------- ! Be careful ! The chip is plainly impossible to detect ! Stupid chip. So every chip with adress in the interval [20..27] could be detected as an MIC74 or a PCF8574. Don't load both drivers. If you have other chips in this address range, the workaround is to load this module after the one for your others chips. On detection, directories are created for each detected chip: /proc/sys/dev/sensors/mic74-<0>-<1>/ where <0> is the bus the chip was detected on (e. g. i2c-0) and <1> the chip address [20..27]: ./mic74-i2c-0-27/ Inside these directories, there are seven files each, one for each of the seven registers in the device. At this point you really need the datasheet. It should be self-explanatory which file is for which register.