[PATCH 2.6] Add class definition to the elektor bus driver

Jean Delvare khali at linux-fr.org
Fri Feb 25 23:31:46 CET 2005

Hi Frank,

> The patch works BUT...
> The PCF8584 device is a bridge, not a hardware monitor. One of the
> other  I2C device types could very well be behind it such as a sound
> chip.  Maybe we could add a BRIDGE type or have it as a I2C_CLASS_ALL
> device.  This is just a suggestion - like I said, the patch works for
> me.

The PCF8584 is an I2C master, as I understand it. It's as much of a
bridge as every other I2C or SMBus master is. The idea of a bridge class
doesn't make any sense to me. A class is meant to isolate chip drivers
from bus drivers. As such, class definitions are carried by bus drivers
and checked by chip drivers. This doesn't leave any room for a bridge
class unless I'm missing something obvious.

Setting class to I2C_CLASS_ALL would somehow defeat our attempt to
isolate different types of I2C busses. It's better to add classes when
it is found that we actually need them.

That being said, I don't know exactly where the PCF8584 is found and
what the Elektor is. Care to tell me what kind of hardware your are
playing with?

Jean Delvare

More information about the lm-sensors mailing list