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

Wolfgang Denk wd at denx.de
Thu Sep 30 19:21:24 CEST 2010


Dear Peter Tyser,

In message <1285851649.22004.5.camel at 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 ?

<me hides />

Best regards,

Wolfgang Denk

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