USB HCD driver

Greg KH gregkh at
Sun Jun 3 17:08:27 EDT 2012

On Sun, Jun 03, 2012 at 07:06:37PM +0100, Simon Arlott wrote:
> I'm giving up on writing a USB HCD driver.
> There's no specification on how to use the hardware, only a mountain of
> documentation on the driver itself which is needlessly full of wrappers
> making it very difficult to understand what it's actually doing.
> I've looked the v16 version of the APM driver and they don't appear to
> know what they're doing, e.g.
> drivers/usb/dwc/cil_intr.c:
> 	BUG_ON(count > 10000);
> I'm trying to get it to compile on ARM. The fact that the patches are
> still failing after 16 revisions may have more to do with inability to
> identify unacceptable code than the structure of the code itself.
> I'm not sure Samsung are capable of writing the HCD driver either:
> This could really use some attention from someone with enough USB
> experience to understand what the original driver is really doing in
> order to rewrite it.

I know a bit about USB :)

I thought that I applied some patches recently that showed up in 3.5-rc1
that should work for this hardware, have you checked there to see if
that really is true or not?

And if not, where would a good place for me to start be?

Oh, and why no documentation on the hardware, I thought we had it around
here somewhere?


greg k-h

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