From: Peter Chen <peter.chen@kernel.org>
To: Pawel Laszczak <pawell@cadence.com>
Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org,
linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH v2] usb: cdnsp: fix issue with ZLP - added TD_SIZE = 1
Date: Thu, 27 Oct 2022 15:24:21 +0800 [thread overview]
Message-ID: <20221027072421.GA75844@nchen-desktop> (raw)
In-Reply-To: <1666620275-139704-1-git-send-email-pawell@cadence.com>
On 22-10-24 10:04:35, Pawel Laszczak wrote:
> Patch modifies the TD_SIZE in TRB before ZLP TRB.
> The TD_SIZE in TRB before ZLP TRB must be set to 1 to force
> processing ZLP TRB by controller.
>
> cc: <stable@vger.kernel.org>
> Fixes: 3d82904559f4 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver")
> Signed-off-by: Pawel Laszczak <pawell@cadence.com>
>
> ---
> Changelog:
> v2:
> - returned value for last TRB must be 0
>
> drivers/usb/cdns3/cdnsp-ring.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/cdns3/cdnsp-ring.c b/drivers/usb/cdns3/cdnsp-ring.c
> index 04dfcaa08dc4..aa79bce89d8a 100644
> --- a/drivers/usb/cdns3/cdnsp-ring.c
> +++ b/drivers/usb/cdns3/cdnsp-ring.c
> @@ -1769,8 +1769,13 @@ static u32 cdnsp_td_remainder(struct cdnsp_device *pdev,
>
> /* One TRB with a zero-length data packet. */
> if (!more_trbs_coming || (transferred == 0 && trb_buff_len == 0) ||
> - trb_buff_len == td_total_len)
> + trb_buff_len == td_total_len) {
> + /* Before ZLP driver needs set TD_SIZE=1. */
> + if (more_trbs_coming)
> + return 1;
> +
> return 0;
> + }
Does that fix the issue you want at bulk transfer, which has zero-length
packet at the last packet? It seems not align with your previous fix.
Would you mind explaining more?
>
> maxp = usb_endpoint_maxp(preq->pep->endpoint.desc);
> total_packet_count = DIV_ROUND_UP(td_total_len, maxp);
> --
> 2.25.1
>
--
Thanks,
Peter Chen
next prev parent reply other threads:[~2022-10-27 7:24 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-24 14:04 [PATCH v2] usb: cdnsp: fix issue with ZLP - added TD_SIZE = 1 Pawel Laszczak
2022-10-27 7:24 ` Peter Chen [this message]
2022-10-27 8:46 ` Pawel Laszczak
2022-11-06 9:02 ` Peter Chen
2022-11-07 5:39 ` Pawel Laszczak
2022-11-10 1:02 ` Peter Chen
2022-11-10 5:38 ` Pawel Laszczak
2022-11-11 1:28 ` Peter Chen
2022-11-15 9:31 ` Pawel Laszczak
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=20221027072421.GA75844@nchen-desktop \
--to=peter.chen@kernel.org \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=pawell@cadence.com \
--cc=stable@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.