Re: PXA27x UDC Power

David Brownell <[email protected]>
Newsgroups gmane.linux.usb.devel
Message-ID <[email protected]>
On Wednesday 28 November 2007, Justin Clacherty wrote:
> David Brownell wrote:
> > I'm not sure I see it as a problem.  At that level, power
> > management is highly product-specific -- if you want anything
> > other than very generic behavior.
>
> Good point :)  Also, I just noticed the fixme for higher powered devices 
> in ether.c.
> 
> > Plus, didn't you say you wanted multiple configurations ... a
> > standard one, and a higher power one for battery recharging?
>   
> We really only want the high powered one but I figured it should at 
> least talk if connected to an unpowered hub.

Yes.


> > You get connected to a host ... the host chooses a configuration
> > it can support.
> 
> I thought that was the case.  My real concern was that I wasn't sure 
> multiple configurations worked properly on the pxa27x.

ISTR the basic problems being (a) hardware limitiation to
at most three configurations, (b) bugs preventing those three
from working sanely, despite  (c) changes between 25x and 27x.


> The pxa27x  
> doesn't seem to like having RNDIS enabled and as far as I can recall it 
> is something to do with the strange way Intel implemented the 
> configurations.  I may have misinterpreted the problem though.

The basic strangeness is the hardware actually caring about
configurations, rather than letting software handle *all* those
issues.  Once they decided to do that, they were hosed first by
constraints in how they designed that hardware (mis)feature and
then by bugs in how they implemented that design.

- Dave

 
> Justin.
> 



-------------------------------------------------------------------------
SF.Net email is sponsored by: The Future of Linux Business White Paper
from Novell.  From the desktop to the data center, Linux is going
mainstream.  Let it simplify your IT future.
http://altfarm.mediaplex.com/ad/ck/8857-50307-18918-4
_______________________________________________
[email protected]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.