Re: [RFC 0/2] USB gadget - configfs

[Joel Becker]

On Thu, Aug 16, 2012 at 03:47:15PM +0200, Sebastian Andrzej Siewior wrote:
> On 08/16/2012 03:17 PM, Andrzej Pietrasiewicz wrote:
> >A lun is "opened" on storing the "file" attribute of the lun, it is in
> >fsg_lun_store_file, storage_common.c. So, again, this is a configfs
> >callback.
> >
> >On storing the connect attribute, the following happens: a composite driver
> >is probed, then all the configurations are iterated over, their functions
> >being bound in turn. After the gadget is set up this way, the host notices
> >connecting a new mass storage device.
> 
> The configuration has to remain unchanged until the "connect" attribute
> is changed (i.e. unconnected). That means the gadget can only be
> reconfigured once it is not active.

	Yes, that's my understanding of the driver code.  What I'm
trying to understand is the trigger for setting connect=1.  See, all of
the other configfs steps you outlined make sense to me as "part of the
gadget's internal state".  While I don't know what C1 and F1 are (I
assume G1 is Gadget1), I don't know that it matters.
	What changes the state to "active"?  That is, what triggers
setting connect=1?  Is it just part of the flow of power-up, or is there
some separation between "setting myself up" and "seeing that a host
wants to talk to me"?

Joel

-- 

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 appreciate it."
	- Franklin P. Jones

			http://www.jlbec.org/
			jlbec@xxxxxxxxxxxx
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