Re: USB driver for Sierra Wireless EM5625/MC5720 1xEVDO modules

From: Andy Gay
Date: Wed Jun 28 2006 - 22:35:12 EST


On Wed, 2006-06-28 at 17:11 -0700, Jeremy Fitzhardinge wrote:
> Andy Gay wrote:
> > - these modules present 3 bulk EPs, the 2nd & 3rd can be used for
> > control & status monitoring while data transfer is in progress on the
> > 1st EP. This is useful (and necessary for my application) so we need to
> > increase the port count.
> >
> Ooh, can you share the details of those EPs?
Probably not, but I'll check. The customer I'm developing for is a
Sierra OEM, so they're probably under an NDA.

The useful port is the second one, it talks a Sierra protocol called CnS
(control and status). You could google for that, I guess. Or ask Sierra
nicely :)

> Is your application public?

>
> > So what should I do next? I see a few possibilities, assuming anyone is
> > interested in this:
> >
> > - I could post a diff from Greg's driver. But I don't have hardware to
> > test whether my changes will break it for the other devices that it
> > supports;
> >
> Well, it is specifically an airprime driver. My card also presents
> another two endpoints, but I don't know what to do with them, so I
> haven't worried about them too much. If they all talk the same thing,
> then they may as well be in the same driver.
I'd think so too, but I can't test that my changes won't break things
for other cards. Just being cautious here...
>
> Are you proposing adding some more protocol knowledge to airprime, or
> just make those EPs appear as more serial ports?
They are just serial ports, there's nothing special the driver can or
should do with them. I just changed the driver so you can get to them.

The main change I made to Greg's driver is to fix the memory leak - it
leaks 16k per endpoint for each open(), that made it unusable on the
very limited memory embedded platform I'm developing for.
>
> Thanks,
> J

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