From: Felipe Balbi <balbi@kernel.org>
To: Thinh Nguyen <Thinh.Nguyen@synopsys.com>,
Thinh Nguyen <Thinh.Nguyen@synopsys.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"linux-usb\@vger.kernel.org" <linux-usb@vger.kernel.org>
Cc: John Youn <John.Youn@synopsys.com>
Subject: Re: [PATCH 1/3] usb: dwc3: gadget: Properly handle failed kick_transfer
Date: Sun, 15 Mar 2020 10:48:05 +0200 [thread overview]
Message-ID: <87o8syf1h6.fsf@kernel.org> (raw)
In-Reply-To: <c17da637-abf1-75b0-e8bf-737958773e8e@synopsys.com>
[-- Attachment #1: Type: text/plain, Size: 1408 bytes --]
Hi,
Thinh Nguyen <Thinh.Nguyen@synopsys.com> writes:
>> Thinh Nguyen <Thinh.Nguyen@synopsys.com> writes:
>>> If dwc3 fails to issue START_TRANSFER/UPDATE_TRANSFER command, then we
>>> should properly end an active transfer and give back all the started
>>> requests. However if it's for an isoc endpoint, the failure maybe due to
>>> bus-expiry status. In this case, don't give back the requests and wait
>>> for the next retry.
>>>
>>> Fixes: 72246da40f37 ("usb: Introduce DesignWare USB3 DRD Driver")
>>> Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
>> could you give some details regarding when does this happen?
>>
>
> So, here are the scenarios in which dwc3_send_gadget_ep_cmd() may return
> a negative errno:
>
> * -EAGAIN: Isoc bus-expiry status
> As you already know, this occurs when we try to schedule isoc too
> late. If we're going to retry the request, don't unmap it.
right
> * -EINVAL: No resource due to issuing START_TRANSFER to an already
> started endpoint
> This happens generally because of SW programming error
Sounds like this should be fixed separately and, probably, we should add
a WARN() so we catch these situations. Have you reproduced this
particular case?
> * -ETIMEDOUT: Polling for CMDACT timed out
> This should not happen unless the controller is dead or in some bad
> state
Understood
--
balbi
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 832 bytes --]
next prev parent reply other threads:[~2020-03-15 8:48 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-13 2:18 [PATCH 0/3] usb: dwc3: gadget: Improve isoc starting mechanism Thinh Nguyen
2020-03-13 2:18 ` [PATCH 1/3] usb: dwc3: gadget: Properly handle failed kick_transfer Thinh Nguyen
2020-03-13 14:20 ` Felipe Balbi
2020-03-13 19:50 ` Thinh Nguyen
2020-03-15 8:48 ` Felipe Balbi [this message]
2020-03-16 0:33 ` Thinh Nguyen
2020-03-16 7:03 ` Felipe Balbi
2020-03-16 19:06 ` Thinh Nguyen
2020-03-29 7:52 ` Felipe Balbi
2020-03-29 23:14 ` Thinh Nguyen
2020-03-13 2:18 ` [PATCH 2/3] ute: dwc3: gadget: Store resource index of start cmd Thinh Nguyen
2020-03-13 2:18 ` [PATCH 3/3] usb: dwc3: gadget: Issue END_TRANSFER to retry isoc transfer Thinh Nguyen
2020-03-13 14:38 ` Felipe Balbi
2020-03-13 20:01 ` Thinh Nguyen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87o8syf1h6.fsf@kernel.org \
--to=balbi@kernel.org \
--cc=John.Youn@synopsys.com \
--cc=Thinh.Nguyen@synopsys.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-usb@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).