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Date:	Wed, 6 Dec 2000 11:38:30 -0800 (PST)
From:	Linus Torvalds <torvalds@transmeta.com>
To:	Erik Mouw <J.A.K.Mouw@ITS.TUDelft.NL>
Subject: Re: test12-pre6



On Wed, 6 Dec 2000, Erik Mouw wrote:
> > 
> > Can you tell me what device it is that doesn't work for you? 
> 
> The USB controller. That's device 00:07.2:
> 
> 00:07.2 USB Controller: Intel Corporation 82440MX USB Universal Host Controller (prog-if 00 [UHCI])
>         Control: I/O+ Mem- BusMaster- SpecCycle- MemWINV- VGASnoop-  ParErr- Stepping- SERR- FastB2B-
>         Status: Cap- 66Mhz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
>         Interrupt: pin D routed to IRQ 11
>         Region 4: I/O ports at fcc0 [size=32]

Now, this is with a bog-standard PIIX irq router, so we definitely know
that we have the pirq table parsing right. I even have unofficial
confirmation from intel engineers on this.

But I see something obviously wrong there: you have busmaster disabled.

Looking into the UHCI controller code, I notice that neither UHCI driver
actually does the (required)

	pci_set_master(dev);

Please add that to just after a successful "pci_enable_device(dev)", and I
just bet your USB will start working.

Johannes, Georg, the above is a fairly embarrassing bug, and is likely to
explain a _lot_ of USB failures (the OHCI driver does do this, btw).

		Linus

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