Hello, with my ohci usb controller problem I came to conclusion that it hangs only during big transfers when ohci usb controller is unable to keep up with rest of the system. That is why it only hangs on fast bulk/iso transfers and not when slow usb keyboard or mouse is used. After being inspired by this uhci usb bugfix (which is very similar to my problem but in my case Nvidia does not provide any driver for windows usb. Just use default windows one): http://osdir.com/ml/linux.usb.user/2002-12/msg00112.html So I modified ohci usb driver source code (ohci-q.c, ohci-hub.c) in similar way by adding mdelay(5); before most of ohci_writel(...) and ohci_readl(...). After recompilation and reboot I used ohci usb without noapic workaround for much longer time without hanging. However after this modification usb hangs immediately after hotpluging other usb device so my ugly hack did not fix all the issues. :( I hope I find here someone who wrote or know Linux ohci driver so he/she knows how to slow down ohci bulk/iso IO operations without breaking hotplug. It looks Linux ohci driver is more aggressive on ohci IO than windows one so making Linux less timing demanding would help my MCP78S keep working. have a nice day, Zbigniew Luszpinski -- 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
