On Fri, Oct 05, 2012 at 02:36:57PM -0700, Sarah Sharp wrote: > On Fri, Oct 05, 2012 at 04:51:53PM -0400, Alan Stern wrote: > > We could add a USB_QUIRK_NO_LPM flag and put a static entry for the > > SIIG hub (and maybe other broken devices) in quirks.c. xhci-hcd could > > set this flag when it sees control transfers timing out or other > > transfer errors. > > I think it would make sense to use the static entry for the SIIG hub, > since the other VIA hubs I have also exhibit this hardware issue, and > they all have the same VID:PID. > > The flag you're talking about is a bit in usb_device->quirks, right? > That would only apply to the particular USB device that's acting up, so > when that device disconnected, the quirks information effectively goes > away, correct? On a replug, the host will see at least one more > transfer error before the flag is re-applied, which isn't great for hard > drives. > > Would it make sense to load the usb_quirks_list into a linked list at > USB core initialization time, and then allow drivers to dynamically add > entries to it? Hmm, so I've tested the VIA hubs under a different Intel chipset (Lynx Point), and they exhibit the same issues as when a bus analyzer is connected on Panther Point. Only the issues show up without the analyzer in between. I'll do some more triaging, but it looks like some devices may work with LPM enabled on some hosts and not others. What do you think about dynamically adding device VID:PIDs to a blacklist? Sarah Sharp -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
