Re: Attaching to an attribute

[Paul Goyette <paul%whooppee.com@localhost>]

On Fri, 8 Dec 2017, Valery Ushakov wrote:

> This, however, still highlights a problem.  How can a module device
> driver attach wsmouse as a child regardless of how the kernel is
> configured.

The device driver module does all appropriate initialization, which 
includes config_init_component().  That ends up calling parent "bus" 
drivers (or other attachment attributes drivers) to "rescan", which 
causes the parents to attach any potential new child.

So, if the configuration has "wsmouse* at wsmousedev?" all drivers 
offering the wsmousedev attribute are told to rescan...  If the 
configuration has specific parents (ie, not attributes), then each of 
those parents get the rescan command.

Note that config(1) doesn't handle

	pseudoroot <attribute>

You need to list each possible parent, even if the attachemt is via an 
attribute:

	pseudoroot ums?
	pseudoroot xxxms?

	wsmouse* at wsmousedev?



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