So. I picked up a Linksys USB200M USB 2.0 ethernet adapter that uses the ASIX Electronics AX88172 chip, and I started cobbling together a driver. This chip uses a series of vendor specific commands to do things like read/write the MII management interface on the MAC, read/write the SROM, set the RX filter, multicast hash table, etc. I can do all this no problem. The Linksys NIC uses a RealTek 8201L PHY, and I can attach it and negotiate a link.
However I can't send or receive any packets. Like all the other USB NICs, packet transfer is supposed to done via bulk in/bulk out endpoints, and I can open these endpoints and initiate transfers just fine, but nothing ever happens. Transmit attempts don't yield any packets on the wire, and I never get any RX transfer completions. (I can see the activity LED on the NIC blink when a frame arrives though.) One thing I have not attempted to do yet (but may try this weekend) is to directly read the RX or TX SRAM (there are commands to let you do this). Frankly, I'm a bit stumped. It looks as though I'm doing everything correctly, but I can't explain why the bulk transfers don't work. Clearly, the control endpoint works, since I can issue commands. There doesn't appear to be any special command that one has to issue to enable/disable the receiver or transmitter on the MAC. I have only one possible explanation. The manual for the AX88172 (http://www.freebsd.org/~wpaul/ASIX/Ax88172.PDF) says the following: "The AX88172 supports 2 interfaces, the interface 0 is Data Interface and interface 1 is for Communication interface." However the USB stack disagrees with the manual on this point: it steadfastly insists that configuration 1 has only 1 interface. So my question, for any USB gurus out there, is: is it possible that the USB stack is wrong on this point, and I really need to be using interface 1 for bulk in/out transfers? I'm a little suspicious at this point, because the stack can't seem to even read the device ID string correctly. (It identifies the chip only as "vendor 0x77b, device 0x2226".) -Bill -- ============================================================================= -Bill Paul (510) 749-2329 | Senior Engineer, Master of Unix-Fu [EMAIL PROTECTED] | Wind River Systems ============================================================================= "If stupidity were a handicap, you'd have the best parking spot." ============================================================================= _______________________________________________ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]"
