Device probe issue with an em(4) compatible device

Brenden Grace bcg at
Wed Sep 29 12:20:25 PDT 2004

On Wed, 2004-09-29 at 13:37, Peter Buckingham wrote:
> why compile the em driver in at all? it won't probe the device if it 
> doesn't exist ;-)

because I need it ...

> otherwise, just add some code to the em's probe routine to check for 
> your subvendor, subdevice pair and exit without attaching.

Well sure (though ugly), but I think having it just return a negative
number would be a better fix than that. I was more interested in why the
em driver (and others) returns 0 and ends the probing of a device that
it could possibly only partially support (based on its matching of
PCI_ANY_ID). If I understand DEVICE_PROBE(9) correctly it seems that the
whole reason for the negative return scale is to avoid this very issue.

Brenden C. Grace

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