> From: vichy [mailto:vichy.kuo@xxxxxxxxx] > Sent: Tuesday, July 22, 2014 9:27 AM > >>>>> My questions are >>>>> 1. The xhci controller seems not handle the normal TRB for short package. >>>>> as you can see the length of event package for normal package is 0. >>>>> am I correct? >>>>> 2. if above #1 is correct, how xhci controller get the left 0x6f8 data >>>>> in original normal package? >>>> >>>> This looks like a hardware bug to me. Which xHCI controller is this? >>> >>> Synopsys >> >> Ouch ;) >> >>>>> the controller did fire iso in token to get 0x4fc bytes, above >>>>> marked "xxxx", and if xhci controller didn't firing the left in tokens >>>>> to get 0x6f8 bytes, that mean the data we get from iso-in pipe is not >>>>> continuous, right? >>>> >>>> I would bet that no data was transferred at all, but the controller >>>> forgot to set the transfer length correctly for the chained normal TRB. >>> >>> so you mean the ISO will be sent but the chained normal TRB won't. >>> that mean the host only get 0x4fc instead of total 0xbf4 Bytes. >>> Am I right? >> >> No, I'm thinking that no data at all was received. That is what the Isoc >> event TRB shows. > > But from isoc event TRB it shows there did get 0x4fc bytes from > device, since the data length of event trb is not 0. No. Read the description of the TRB Transfer Length field in section 6.4.2.1 of the xHCI spec. "This field shall reflect the residual number of bytes not transferred". >>>> Are you seeing an actual problem with this? If not, maybe the xHCI driver >>>> is written in such a way that this does not cause a problem. >>> >>> I found this problem because when I activate ISO for my webcam, I get >>> below message >>> "ERROR Transfer event TRB DMA ptr not part of current TD" >> >> Yes, but does the webcam work? Without the patch that you mentioned >> below, you will get these messages, but they shouldn't cause any >> functional problem. > > we will try to eliminate the message and check whether webcam is ok. > >> Also, which webcam is this? Maybe I can try to reproduce the problem >> here. > > And normal uvc webcam will have this issue.(But you have to purposely > disable "XHCI_SPURIOUS_SUCCESS") ?? Why would you purposely disable XHCI_SPURIOUS_SUCCESS? It is there for a reason. >> Which version of the kernel are you using? Please try this with the >> latest version (3.16-rc5) to make sure this is not some problem that >> has already been fixed. > > the version I use is 3.8.2. > I will try to merge 3.16-rc5 into our system. Good. -- Paul ��.n��������+%������w��{.n�����{���)�� jg��� �����ݢj����G���� ���j:+v���w�m������w�������h�����٥
