wd at denx.de
Sun Dec 20 05:56:57 EST 2009
Dear Hunter Cobbs,
In message <1261190115.14590.5.camel at mobiLinux> you wrote:
> Hello list. I've run into a rather odd problem. I seem to have a
> problem with full-speed isochronous transfers across a USB2.0 Hub. I
> believe this was observed before with the general EHCI drivers in Linux.
Which exazct kernel / driver cversions are you talking about?
> In the latest branch of the kernel, the EHCI driver has some "Enhanced
> Transaction Translation" scheduling. This would be great for me to use
> as it seems to directly address the issues I've seen. However, I'm not
> really sure on how to proceed because the DWC_OTG driver is not GPL code
Oops? if that wa the case you could not use (and distribute) this code
in a Linux context at all.
> while the EHCI code I'd like to use is. Therefore, I don't believe that
> I can port the Enhanced Transaction Translation routine into the DWC_OTG
> driver without violating both the GPL and Synopsis's own driver.
What makes you think so?
The Synopsis dwc_otg driver license does not seem to be in conflict
to the GPL, if you ask me (but then, I am not a layer). When we
worked on this, we were assured that the use of this driver source in
the context of GPLed software like the Linux kernel (or U-Boot) was
not considered an issue by Synopsis.
> Does anyone have a suggestion on how to proceed?
We have been doing some work on the DWC drivers in the past, fixing a
number of issues. [We never attempted to psuh any of this into
mainline as the Synopsis drivers are - in our opinion - not
avcceptable for mainline but require more or less a rewrite from
scratch. But you can find all this stuff in our linux-2.6-denx repo.]
I recommend you give a try to our latest stable branch.
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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