On Tue, Mar 31, 2015 at 10:02:52AM -0400, Alan Stern wrote: > On Tue, 31 Mar 2015, Peter Chen wrote: > > > I reproduced this issue, I can't see the fifth endpoints during the SoFs > > although the time to SoF boundary is about 800us, see attached. > > > > - At transaction 3749, the third UAC2 gadget is ready to send/receive > > data. > > - At next SoF periods, the first and the second devices send/receive > > data. > > - At transaction 3754, the third device's OUT is on the bus, but the > > address 11's OUT is disappeared. > > > > I reported this problem to IC team, but they are on new SoC validation > > periods, they said they will simulate it after new project has finished. > > That's great! I'm happy that you were able to duplicate the problem. > Please let me know what the IC team has to say when they look at it. > > Do you know whether Freescale's root-hub TT implementation was done > in-house? Or was it based on the old ARC/TDI IP? It's possible that a > lot of different kinds of host controllers suffer from this problem. > > Alan Stern > Hi Alan, I am not sure if you have noticed the patch[1], it is the solution for this issue, in the RTL, the default reserved time for one packet is 1023 bytes for siTD, so after 4 * 64 packets has transfered, the reserved time is not enough for 1023 bytes packet. This issue should exist at all ARC/Chipidea cores. [1] http://www.spinics.net/lists/linux-usb/msg126278.html -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
