> >>> > >>> Further down in the mailing list chain Peter Chen states > >>>> Besides, do not connect HUB between your host board and emulation > >>>> board (for sending VID/PID). > >>> but there is no additional information regarding this statement. > >> EHSET is used to test embedded host electrical signal required by USB > >> IF Compliance Test, not test the signal for USB HUB, since the EHSET > >> module could only let embedded host controller enter test mode by > >> writing TEST MODE registers follows EHCI or xHCI spec. Maybe the USB > >> HUB could let its port enter test mode, but it needs to use other > >> ways, maybe vendor specific commands. > > > >IMO ehset should work with external HUB as well since all it takes to put a > >HUB's > port in compliance mode is sending a SetFeature request which I believe driver > already does. If HUB is sending stall then you can try putting a different > port in > compliance which is not connected. > > How do I specify which port I put in compliance? The way I have been doing it > was > using a PIDVID from testusb.com which, as I understand it, turns into the > correct > device by setting its VID and PID so by nature of how it works I must have a > "device" connected. >
Which port your test device is connected, then which port will enter test mode, it is controlled by EHSET. The test device's VID/PID must be the same with ehset_id_table in ehset.c. For external HUB, I have never done since I only test USB controller on SoC. As Manu said, if it supports the commands in EHSET in its firmware, it should support put its downstream port in test mode. Peter
