Discussion of the implementations of VIRTIO specification
 help / color / mirror / Atom feed
From: Jie Deng <jie.deng@intel.com>
To: Paolo Bonzini <pbonzini@redhat.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Cornelia Huck <cohuck@redhat.com>
Cc: virtio-comment@lists.oasis-open.org, virtio-dev@lists.oasis-open.org
Subject: Re: [virtio-comment] [PATCH v3] virtio-i2c: add the device specification
Date: Wed, 4 Nov 2020 16:05:50 +0800	[thread overview]
Message-ID: <a1497eb0-91c0-551f-37e2-041b91c68e4b@intel.com> (raw)
In-Reply-To: <f0a25b9d-c1e7-21e8-0944-9fa5796adfca@redhat.com>


On 2020/10/29 4:10, Paolo Bonzini wrote:
> On 27/10/20 07:00, Jie Deng wrote:
>> +The driver queues requests to the virtqueue, and they are used by the
>> +device. The request is the representation of one segment of an I2C
>> +transaction. Each request is of form:
>> +
>> +\begin{lstlisting}
>> +struct virtio_i2c_req {
>> +        le16 addr;
>> +        le16 flags;
>> +        le16 len;
>> +        u8 buf[];
>> +        u8 status;
>> +};
>> +\end{lstlisting}
> Hi,
>
> one extremely common two-segment I2C transaction is not reproducible
> with virtio-i2c.  This is when a write is followed by a read: the master
> starts off the transmission with a write, then sends a second START,
> then continues with a read from the same address.
>
> Would it make sense to define the request like
>
> struct virtio_i2c_req {
> 	le16 addr;
> 	le16 written;
> 	le16 read;
> 	u8 bufwrite[];
> 	u8 status;
> 	u8 bufread[];
> };
>
> instead?
>
> Thanks,
>
> Paolo

Hi,

Do you have any comments on Paolo's proposal ?

Thanks.


This publicly archived list offers a means to provide input to the
OASIS Virtual I/O Device (VIRTIO) TC.

In order to verify user consent to the Feedback License terms and
to minimize spam in the list archive, subscription is required
before posting.

Subscribe: virtio-comment-subscribe@lists.oasis-open.org
Unsubscribe: virtio-comment-unsubscribe@lists.oasis-open.org
List help: virtio-comment-help@lists.oasis-open.org
List archive: https://lists.oasis-open.org/archives/virtio-comment/
Feedback License: https://www.oasis-open.org/who/ipr/feedback_license.pdf
List Guidelines: https://www.oasis-open.org/policies-guidelines/mailing-lists
Committee: https://www.oasis-open.org/committees/virtio/
Join OASIS: https://www.oasis-open.org/join/


      parent reply	other threads:[~2020-11-04  8:05 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-27  6:00 [virtio-comment] [PATCH v3] virtio-i2c: add the device specification Jie Deng
2020-10-27 12:20 ` [virtio-comment] " Michael S. Tsirkin
2020-10-28  7:54   ` Jie Deng
2020-10-28 11:27     ` Michael S. Tsirkin
2020-10-29  2:20       ` Jie Deng
2020-10-28 20:10 ` [virtio-comment] " Paolo Bonzini
2020-10-29  7:38   ` Jie Deng
2020-11-04  8:05   ` Jie Deng [this message]

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=a1497eb0-91c0-551f-37e2-041b91c68e4b@intel.com \
    --to=jie.deng@intel.com \
    --cc=cohuck@redhat.com \
    --cc=mst@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=virtio-comment@lists.oasis-open.org \
    --cc=virtio-dev@lists.oasis-open.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