[10/14] usb: dwc3: gadget: remove wait_end_transfer

[Felipe Balbi <felipe.balbi@linux.intel.com>]

Hi,

Thinh Nguyen <thinh.nguyen@synopsys.com> writes:
>>>>> Try to dequeue a request that was already completed. Odd. Why are we
>>>>> missing a call to giveback??
>>>> Got a little more information:
>>>>
>>>>     file-storage-3982  [006] d...   131.010663: dwc3_ep_queue: ep1in: req 00000000eccaa10f length 0/16384 zsI ==> -115
>>>>     file-storage-3982  [006] d...   131.010667: dwc3_prepare_trb: ep1in: trb 000000002ab8a1f9 buf 00000000bde24000 size 16384 ctrl 00000811 (Hlcs:sC:normal)
>>>>     file-storage-3982  [006] d...   131.010674: dwc3_gadget_ep_cmd: ep1in: cmd 'Update Transfer' [30007] params 00000000 00000000 00000000 --> status: Successful
>>>>      irq/16-dwc3-3983  [004] d...   131.010942: dwc3_event: event (00004086): ep1in: Transfer In Progress [0] (sIm)
>>>>      irq/16-dwc3-3983  [004] d...   131.010942: dwc3_complete_trb: ep1in: trb 00000000426cd8cf buf 00000000bde20000 size 0 ctrl 00000810 (hlcs:sC:normal)
>>>>      irq/16-dwc3-3983  [004] d...   131.010944: dwc3_gadget_giveback: ep1in: req 00000000f7765e56 length 16384/16384 zsI ==> 0
>>>>     file-storage-3982  [006] d...   131.010994: dwc3_ep_queue: ep1in: req 00000000f7765e56 length 0/16384 zsI ==> -115
>>>>     file-storage-3982  [006] d...   131.010998: dwc3_prepare_trb: ep1in: trb 0000000065d9143d buf 00000000bde28000 size 16384 ctrl 00000811 (Hlcs:sC:normal)
>>>>     file-storage-3982  [006] d...   131.011005: dwc3_gadget_ep_cmd: ep1in: cmd 'Update Transfer' [30007] params 00000000 00000000 00000000 --> status: Successful
>>>>      irq/16-dwc3-3983  [004] d...   131.065517: dwc3_event: event (00000001): Disconnect: [U0]
>>>>     file-storage-3982  [006] ....   131.065558: dwc3_ep_dequeue: ep1in: req 00000000f7765e56 length 0/16384 zsI ==> -115
>>>>     file-storage-3982  [006] d...   131.065687: dwc3_gadget_ep_cmd: ep1in: cmd 'End Transfer' [30d08] params 00000000 00000000 00000000 --> status: Successful
>>>>      irq/16-dwc3-3983  [004] d...   131.065729: dwc3_event: event (080301c6): ep1in: Endpoint Command Complete
>>>>      irq/16-dwc3-3983  [004] d...   131.065731: dwc3_gadget_giveback: ep1in: req 00000000f7765e56 length 0/16384 zsI ==> -104
>>>>     file-storage-3982  [006] ....   131.065766: dwc3_ep_dequeue: ep1in: req 00000000eccaa10f length 0/16384 zsI ==> -115
>>>>      irq/16-dwc3-3983  [004] d...   135.071714: dwc3_event: event (00000101): Reset [U0]
>>>>      irq/16-dwc3-3983  [004] d...   135.126440: dwc3_event: event (00000201): Connection Done [U0]
>>>>
>>>> From this snippet above it seems like we got End Transfer completed
>>>> *before* we tried to dequeue the request. This is a race in the driver,
>>>> since it will wait for End Transfer complete forever :-p We can see that
>>>> ep_dequeue won't send a new End Transfer unless it's necessary:
>
> Right. That was what I try to point in my previous reply.
>
>>>>
>>>> static void dwc3_stop_active_transfer(struct dwc3_ep *dep, bool force)
>>>> {
>>>> 	struct dwc3 *dwc = dep->dwc;
>>>> 	struct dwc3_gadget_ep_cmd_params params;
>>>> 	u32 cmd;
>>>> 	int ret;
>>>>
>>>> 	if ((dep->flags & DWC3_EP_END_TRANSFER_PENDING) ||
>>>> 	    !dep->resource_index)
>>>> 		return;
>>>> [...]
>>>> }
>>>>
>>>> So this will wait forever. Here's a patch that takes into consideration
>>>> this possibility:
>>> a version that compiles now (#facepalm):
>> I've prepared a branch with a few patches on top of my testing/fixes to
>> test this out. Seems to work fine on my end. Can you try with your test
>> setup?
>
> I think you need to fix this:

indeed, I was thinking about this some more and came up with the same
thing. I'll update all patches and force update the branch, then send
final patches to mailing list.

Thank you