Subject: Re: i2c
To: Matt Thomas <matt@3am-software.com>
From: Garrett D'Amore <garrett_damore@tadpole.com>
List: tech-embed
Date: 05/30/2006 21:30:23
Matt Thomas wrote:
> Jachym Holecek wrote:
>> Hello,
>>
>> # Christopher Beck 2006-06-05:
>>> I've seen NetBSD supports i2c, but i don't know how to use it. Is
>>> there a special Device and/or a lib with that I can acces it? I want
>>> to connect my Atmels and other NetBSD PCs together (just to give
>>> commands to other units). Has anyone an idea or a link to a HowTo
>>> for me?
>>
>> Well, ${sys}/dev/i2c/i2c_io.h sketches an ioctl() interface to I2C bus,
>> but it's not actually exported to userland anywhere (ie. I2C controllers
>> are not attached to device files), AFAICS. This means that currently,
>> the I2C API is kernel-only.
>>
>> Exposing it to userland shouldn't be hard, please file a PR so that it
>> doesn't get forgotten (unless you want to implement it yourself ;-).
>
> Exporting i2c generically to userland is a bad idea. A suitable
> abstraction
> for the device(s) would be designed and implemented instead.

Having recently looked at i2c, I agree completely with this.

    -- Garrett

-- 
Garrett D'Amore, Principal Software Engineer
Tadpole Computer / Computing Technologies Division,
General Dynamics C4 Systems
http://www.tadpolecomputer.com/
Phone: 951 325-2134  Fax: 951 325-2191