Alan Stern <[EMAIL PROTECTED]>@lists.sourceforge.net wrote:
... snip ... >> >No, it is normal. When no devices are attached the driver halts the >> >controller to reduce PCI utilization and avoid DMA activity, thereby >> >permitting improved power management. >> > >> Then is it safe to assume, the controller starts _itself_ up when it detects >> a change in one of its busses? > >No. The controller notifies the driver by an interrupt and the driver >starts the controller. However, connection status detection works even >when the controller is halted. In fact, it is connection status detection >that _causes_ the controller to raise the interrupt request. Then can you point me to what routine in what file, is responsible for receiving the interrupt and then starts the controller. The first thing to prove is that the interrupt never happens. Then to figure out why. Could this be related to acpi? If so, what can we look at? I tried booting the kernel with acpi=off, but again... no effect. I was reading a little last night in the Intel ICH4 chip manual, about the 'halt' state and that the controller needs to be 'reset' and given a timeout before continuing. Where is this code (what routine/file)? Because I'd like to fix it/get it fixed, but I need help/direction from the USB driver gurus. :-) What is the relationship between?: uhci-hub.c, uhci-hcd.c, ehci-hub.c, ehci-hcd.c hub.c and hcd.c I know its a big thing to ask, but ?is? there a high level flow diagram of how the Linux USB driver thing/family is supposed to work and what software/sobroutines performs what part of that flow? ------------------------------------------------------- This SF.Net email is sponsored by: Oracle 10g Get certified on the hottest thing ever to hit the market... Oracle 10g. Take an Oracle 10g class now, and we'll give you the exam FREE. http://ads.osdn.com/?ad_id=3149&alloc_id=8166&op=click _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
