Hi balbi,
Thanks for reponse. Now I fixed this case without check STALL status
when clear-Halt request.
BDW, I have meet other case:
Run dwc3 for uvc function, the uvc video show video overlapping when windows 7
restart camera app.
I debug the dwc3 drivers ,found :
1. when camera app close, the dwc3 ep_dequeue is call. Then giveback
request with status: -ECONNRESET to uvc function layer. dep->trb_dequeue keep
stable
2.when camera app reopen ,the dwc3 ep_queue is call. Then kick a
transfer, fetch a new trb to dwc3 core. dep->trb_enqueue increment.
3.when one trb tranfter complete, handle event process function fetch
one frb by current dep->trb_dequeue, and uvc function would get one request
complete giveback, which have been dequeue.
But in fact, current dep->trb_dequeue pointer buffer is "old",
because stp1 have been dequeue it.
Current dwc3 drivers: the correct enqueue req process is " ep
enqueue > fetch a new trb by trb_enqueue > increase trb_enqueue > pack trb to
dwc3 core", Right?
For dequeue request process, now is " ep dequeue > stop started_list
request > giveback request with -ECONNRESET status" Right ?
To avoid getting a older request which has been dequeued, I think dequeue
process necessary sync the trb_dequeue to trb_enqueue. Right ?
Liang Shengjun
-----邮件原件-----
发件人: Felipe Balbi [mailto:felipe.ba...@linux.intel.com]
发送时间: 2018年6月25日 15:48
收件人: Alan Stern <st...@rowland.harvard.edu>
抄送: liangshengjun <liangsheng...@hisilicon.com>; sta...@vger.kernel.org;
linux-usb@vger.kernel.org
主题: Re: make a confirm for [usb: dwc3: gadget: skip Set/Clear Halt when invalid]
Hi,
Alan Stern <st...@rowland.harvard.edu> writes:
>> that patch is not 100% correct. You can revert it in your tree. I
>> added that because of a problem I found when running adb against macOS.
>>
>> It's actually okay to send Clear Halt at any time, but for some
>> reason
>> dwc3 was hanging when running adb against macOS.
>
> Note: According to the USB spec it's okay to send Clear-Halt at any
> time. But there are plenty of devices that get upset if they receive
> this message when the endpoint isn't actually halted.
right. The weird thing here is that dwc3 has never suffered from this until we
ran ADB against macOS. That was the only way to get any problems.
Without clear halt, though, we have no means for syncing data toggle.
--
balbi
