Hi Jim, > I am coding a usb host driver on an embedded ARM processor (ep93xx), the > ohci-ep93xx started fine (please see following messages) with bus number > 1. Then, after plugging a device to the host, it detected the device and > started a hub init process. But the hub.c printed out an error of > "device not accepting address 2". Why the ep93xx started with bus > address 1 while the hub was looking for bus address 2? What I was > missing here? Because the device can be detected by the usb host, can I > say at least the hardware and device driver level works? Any tips to > help me debug are appreciated.
Bus number and device addresses are different things. As a system can have several USB busses, each bus gets assigned a number. Your bus is the first USB bus to be detected on the system, so it gets assigned number 1. When you plugged the device on the bus, the host controller detected the plug event and reported it to the kernel. The USB subsystem then assigns an address to the device. The hub got address 1, so your device gets address 2. Nothing surprising there. > ep93xx usb: init > ep93xxusb ep93xxusb0: new USB bus registered, assigned bus number 1 > ep93xx usb: start > usb usb1: Product: EP93XX OHCI > usb usb1: SerialNumber: ep93xx_usb > hub 1-0:1.0: USB hub found > hub 1-0:1.0: 3 ports detected > > > usb 1-3: new full speed USB device using address 2 > usb 1-3: device not accepting address 2, error -110 > usb 1-3: new full speed USB device using address 3 > usb 1-3: device not accepting address 3, error -110 -110 means -ETIMEOUT. The USB subsystem tried to sent a SET_ADDRESS request to the device, but not response was received. This either means that the device didn't answer, or that the host controller did something wrong. The second is unfortunately much more likely, so this means your driver still needs debugging :-) Cheers, Laurent Pinchart ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
