[U-Boot] [PATCH 13/17] post/i2c: Add ability to ignore I2C devices

Heiko Schocher
2010-10-01T06:29:19Z

Hello Wolfgang,

Wolfgang Denk wrote:
> Dear Peter Tyser,
>
> In message <1285851649.22004.5.camel@ptyser-laptop> you wrote:
>> Currently the POST code makes sure every entry in the white list is
>> found, but it also considers any unexpected devices found an error. Eg
>> you plug in a daughter card with an EEPROM on it that isn't listed in
>> I2C_ADDR_LIST, and the POST fails with:
>> I2C: addr 50 not expected
>
> Yes, and this is actually intentional.
>
>> As an alternative to this patch we could not treat unexpected devices as
>> an error, but you'd lose a small amount of POST coverage and
>> flexibility.
>
> No, we don't want to do this.
>
> So the IGNORE_LIST is intended for devices that may or may not be
> present, and neither state is considered an error?
>
>
>>>>> I2C_POST_ADDR_IGNORE_LIST
>>>> I was following the lead of the existing I2C_ADDR_LIST define. Agreed
>>>> it should be named differently. I'll go with CONFIG_SYS_POST_I2C_ADDRS
>>>> and CONFIG_SYS_POST_I2C_IGNORES unless someone else chimes in.
>>> Argh... I don't like identifiers that need half a line or more...
>> Agreed, but its hard when over half the name is the mandatory
>> CONFIG_SYS_POST_ prefix. Any suggestions?
>
> Omit that ?

:-(

... this is not only here a problem, this problem occurs *all* over
the code, because we have defined that we use CONFIG_SYS_ or CONFIG_
prefixes ... see README "Software Configuration" ...

and yes, this is a long fix prefix definition ... especially if
we want to add subsystem prefixes like I2C, POST, USB (which I think
is not a bad thing) ... then definelength will grow ...

bye,
Heiko