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+MODULE: i2c-stub
+
+DESCRIPTION:
+
+This module is a very simple fake I2C/SMBus driver.  It implements four
+types of SMBus commands: write quick, (r/w) byte, (r/w) byte data, and
+(r/w) word data.
+
+You need to provide chip addresses as a module parameter when loading this
+driver, which will then only react to SMBus commands to these addresses.
+
+No hardware is needed nor associated with this module.  It will accept write
+quick commands to the specified addresses; it will respond to the other
+commands (also to the specified addresses) by reading from or writing to
+arrays in memory.  It will also spam the kernel logs for every command it
+handles.
+
+A pointer register with auto-increment is implemented for all byte
+operations.  This allows for continuous byte reads like those supported by
+EEPROMs, among others.
+
+The typical use-case is like this:
+	1. load this module
+	2. use i2cset (from lm_sensors project) to pre-load some data
+	3. load the target sensors chip driver module
+	4. observe its behavior in the kernel log
+
+There's a script named i2c-stub-from-dump in the i2c-tools package which
+can load register values automatically from a chip dump.
+
+PARAMETERS:
+
+int chip_addr[10]:
+	The SMBus addresses to emulate chips at.
+
+CAVEATS:
+
+If your target driver polls some byte or word waiting for it to change, the
+stub could lock it up.  Use i2cset to unlock it.
+
+If the hardware for your driver has banked registers (e.g. Winbond sensors
+chips) this module will not work well - although it could be extended to
+support that pretty easily.
+
+If you spam it hard enough, printk can be lossy.  This module really wants
+something like relayfs.
+