i2c-stub-from-dump Man page

I2C-STUB-FROM-DUMP(8) System Manager’s Manual I2C-STUB-FROM-DUMP(8)

NAME

i2c-stub-from-dump – feed i2c-stub with dump files

SYNOPSIS

i2c-stub-from-dump address[,address,…] dump-file [dump-file …]

DESCRIPTION

i2c-stub-from-dump is a small helper script for the i2c-stub kernel
driver. It lets you setup one or more fake I2C chips on the i2c-stub
bus based on dumps of the chips you want to emulate.

i2c-stub-from-dump requires i2cdetect and i2cset to be installed and
reachable through the user’s PATH. The former is used to find out the
i2c-stub bus number, while the latter is used to write to the fake I2C
chips.

EXAMPLE
You have an I2C chip on system A. You would like to do some development
on its driver on system B. Here are the few steps you have to follow.

On system A, use i2cdump to capture a dump from the chip. Assuming that
the chip in question lives at address 0x4c on I2C bus 0, you would run:

i2cdump -y 0 0x4c b > chip.dump

Adjust the bus number and chip address for your case. i2cdetect can
help you find out their values. If the device uses word (16-bit) regis‐
ter access instead of the traditional byte (8-bit) access, use mode w
instead of b.

Copy the dump file to system B.

On system B, run:

i2c-stub-from-dump 0x4c chip.dump

This will load the required i2c-dev and i2c-stub kernel drivers if
needed, then write all the register values to the emulated I2C chip at
address 0x4c. Again, adjust the address as needed.

LIMITATIONS
There are some limitations to the kind of devices that can be handled:

· Device must not have banks (as most Winbond devices do).

SEE ALSO

i2cdump(8), i2cdetect(8), i2cset(8)

AUTHOR

Jean Delvare

March 2010 I2C-STUB-FROM-DUMP(8)