Hello everybody, I had an issue with the integration of our ehci and ohci drivers(these drivers are not developed by microsoft and not the 'usbehci.sys' and 'usbohci.sys' drivers coming along with the winxp operating system) and so thought of putting forth a query in this mailing list. We had developed our ehci and the ohci drivers(ehci.sys and ohci.sys) in a winxp system and as per the wdm model. The drivers alone are working fine - detecting device attach-detach, generating sofs, enumerating the attached devices and also performing all of the control, bulk, interrupt and iso xfers. Even when we load the windows ehci driver(usbehci.sys) and our customized ohci driver(ohci.sys) or our customized ehci driver(ehci.sys) and the windows ohci driver(usbohci.sys), the operations are fine with our customized drivers as well as the windows drivers. But the problem comes up, when we install both of our customized drivers(ehci.sys and ohci.sys) in the winxp system. What we are observing here is that, when we attach a FS mass storage device to the USB port for the first time, at first our ehci driver gets invoked and after it has detected that the attached device is a FS device, it transfers ownership to the ohci driver. The ohci driver then takes care of the required port reset and enabling of the port and all the device enumeration and xfers can be done through it to the mass storage device. When again we detach this FS mass storage device from the USB port and attach it back after a definite interval of time for the second time, in this case, we see that control has moved to the ehci driver as in the previous case and even the ownwership xfer to the ohci driver is done by the ehci driver, but the ohci driver does not seem to get invoked so as to perform the required port reset and enable. As the same code which worked for the first time, should be working for the second time also, we are not able to locate the cause of the problem. We had cross verified the ehci and ohci specs and found that everything seems to have been implemented in the drivers as mentioned the specs. Has anyone experienced such an issue in the past and can help me with a solution on this? Would be grateful if provided help. Note that in the presence of both the drivers, if we attach and detach HS devices from the system, the HS device functions appropriately through the ehci driver. But the issue is with the attachment of FS/LS devices. Thanking you in advance. With Regards, Monisha. ===== Success is a journey, not a destination. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.opencores.org/forums.cgi/usb/attachments/20051118/03815cbf/attachment-0001.html