> There stay 3 main questions:
> 1. How is ensured that hcd und hd do not access simultaneously that data
> structure?
usb-uhci.c
imho:
1. At initialisation tds are written before hc is started, initskel
after starthc.
2. At urb submission tds are written in uhci_submit_iso_urb, but linked
with fr
Hi,
>
> > 2. I do neither know what is the enqueue() nor do I find an identifier
> > with that name.
> > But if I understand you right your statement does not answer my
> > question.
> > I want to know where in usb-uhci.c transfer is triggered (at
> > hardwarelevel).( in order to conclude how it i
> 2. I do neither know what is the enqueue() nor do I find an identifier
> with that name.
> But if I understand you right your statement does not answer my
> question.
> I want to know where in usb-uhci.c transfer is triggered (at
> hardwarelevel).( in order to conclude how it is working periodic
Hi,
>
> > Where in particular is the point where hcd says to hc: now do transfer!?
>
> In the enqueue() method when it patches the queues that
> the HC will be reading (using DMA). All the HCs have
> some kind of "transfer descriptors" (TDs), read by the
> controller. EHCI has three different t
Three main ways to understand how the Linux-USB stack works:
- Use the USB 2.0 spec. (1.1 is obsolete now.)
- Use The Source! Turn on all the debugging info you can,
and run things too. I'd strongly recommend looking at
the ohci-hcd code for HC level stuff ... it's simplest,
and it
> Sure, "queue_urb" puts the urb in the list of pending urbs, and in the
> interrupt routine thread "process_urb" picks them up, but here is where
> I loose track.
> Where in particular is the point where hcd says to hc: now do transfer!?
> How are the synchronisation mechanisms implemented in thi
On Wed, Feb 04, 2004 at 10:07:03AM +0100, [EMAIL PROTECTED] wrote:
> Hello all,
> you might think I am crazy but my aim is to get a usb-driver for rtai,
> as there is none. I have only a cpia camera there to test.(P3, 2.4.21)
> Now I am trying to understand the usb subsystem as a whole. Newbie, who
Hello all,
you might think I am crazy but my aim is to get a usb-driver for rtai,
as there is none. I have only a cpia camera there to test.(P3, 2.4.21)
Now I am trying to understand the usb subsystem as a whole. Newbie, who
am i, I have read _anything_ related to the usb-core, like the usb
Program
Hello all,
you might think I am crazy but my aim is to get a usb-driver for rtai,
as there is none. I have only a cpia camera there to test.(P3, 2.4.21)
Now I am trying to understand the usb subsystem as a whole. Newbie, who
am i, I have read _anything_ related to the usb-core, like the usb
Program
