Messages in this thread | | | From | David Brownell <> | Subject | Re: EHCI Regression in 2.6.23-rc2 | Date | Tue, 14 Aug 2007 01:01:19 -0700 |
| |
On Monday 13 August 2007, Daniel Exner wrote: > David Brownell wrote: > > On Monday 13 August 2007, Stuart_Hayes@dell.com wrote: > > > With the VIA controller I have, > > > > Which kind is that? The VT6202 is buggy as all get-out, and > > they sold a *LOT* of those discrete chips for use in add-on PCI > > cards. We generally warn people away from those. A more current > > version is the VT6212, which was much more usable. (If it says > > EHCI 0.95, it's a VT6202... their EHCI 1.0 chips were much better.) > > Where exactly should I search for this? Neither lspci nor lsusb showed any > hint on the EHCI rev. the chip conforms to..
The driver logs that information as it starts; on this sytem:
ehci_hcd 0000:00:02.2: USB 2.0 started, EHCI 1.00, driver 10 Dec 2004
vs "EHCI 0.95".
> [..] > > > Perhaps for now the best thing would just be to bypass the EHCI CPU > > > frequency notifier code (i.e., my patch) for VIA EHCI controllers, since > > > they are broken. Would a hard-coded blacklist (just an "if > > > (manufacturer==VIA)..." type thing) be OK? > > > > Yes ... although if you don't need to blacklist their EHCI 1.0 chips > > don't do it. (Any VIA EHCI integrated into a southbridge is going > > to follow spec rev 1.0 pretty well, modulo idiosyncratic timings.) > > I guess its needed to blacklist even the ECHI 1.0 chips, since my problem is > with exactly one of those ;)
Something doesn't add up then ... above you ask where to find that info, but here you say you already got it from somwhere ... ?
> I'm not really into USB protocol specs, but perhaps its possible to test > wether the problem Stuarts patch addressed can actually happen on VIA EHCI > chips? Perhaps those guys solved the problem in Hard/Firmware..
Theoretically possible, and I've certainly seen hardware made to do stranger things than that.
> > > I've also acquired a card with an NEC EHCI controller on it, which I'm > > > going to look at while I'm into it... > > > > Another case where there are a lot of add-on "EHCI 0.95" cards; but > > in this case the quirks were less significant. > > Some guy donated me a PCMCIA card with one of those, cause it'll wont work in > his Windows only Notebook :)
A NEC 0.95 ?? Should be fine with Linux. Assuming no bugs have crept in.
- Dave
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |