On Wed, 2003-01-15 at 19:38, David Brownell wrote:
> oliverthered wrote:
> > On Wed, 2003-01-15 at 17:42, David Brownell wrote:
> > 
> >>>+          if(!(ep_desc = usb_epnum_to_ep_desc(ps->dev, uurb.endpoint)))
> >>>+                  return -ENOENT;
> >>>+          interval = ep_desc->bInterval;
> >>>+          
> >>
> >>Shouldn't it be "interval = 1 << (ep_desc->bInterval -1);" instead?
> >>For iso, bInterval is always a log2 encoding.
> > 
> > 
> > Is this also true for interrupt or just ISO?
> 
> What it says in the USB 2.0 spec:  true for high speed interrupt
> as well as all ISO endpoints.
> 
> Full and low speed interrupt endpoints use a linear encoding
> (with an effective max interval 128msec).

Ok so usb_device.speed  needs to be checked against usb_device_speed.

also.... (from usb.h)
* Interrupt UBS must provide an interval, saying how often (in
milliseconds
* or, for highspeed devices, 125 microsecond units)


I take it bInterval is log2(microframes)

 
-- 
oliverthered <[EMAIL PROTECTED]>



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