Re: [RFC/PATCH 2/2] usb: ehci: Add support for SINGLE_STEP_SET_FEATURE test of EHSET

[Felipe Balbi <balbi@ti.com>]

[-- Attachment #1: Type: text/plain, Size: 1393 bytes --]

Hi,

On Fri, Aug 09, 2013 at 10:37:50AM -0400, Alan Stern wrote:
> > > > Wait a minute, didn't we discuss a while back that these test features
> > > > should be built into usbcore so that we could have a usbcv clone for
> > > > linux ?
> > > 
> > > There's no way this can be built into the core.  This test requires the
> > > behavior of the host controller to be modified at a low level
> > > (introducing a 15-second delay between the Setup and Data stages of a
> > > control transfer).  Only the HCD can do that.
> > 
> > heh, it doesn't need to be entirely in the core. Core could have the
> > generic calls and HCDs could implement some callbacks, but I think quite
> > a bit of the code will be similar if we implement the same thing on all
> > HCDs.
> 
> What generic calls and callbacks would you suggest?  I assume you want 
> enough to cover not just this one test but the entire USB-CV suite.

maybe a single callback for supporting 'testmodes' ? which receives the
test mode as argument ?

> > > Besides, doesn't USB-CV install its own version of Windows' EHCI driver 
> > > while it runs its tests?
> > 
> > IIRC only USB20CV, the new USB30CV (which also tests USB2) doesn't do
> > that.
> 
> I don't have more than the foggiest notion of how these things really
> work under Windows.

and that's hardly necessary to understand...

-- 
balbi

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]