linux-media.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
To: Hans de Goede <hdegoede@redhat.com>, Hans Verkuil <hverkuil@xs4all.nl>
Cc: linux-media <linux-media@vger.kernel.org>, workshop-2011@linuxtv.org
Subject: Re: [Workshop-2011] RFC: V4L2 API ambiguities
Date: Mon, 13 Aug 2012 21:15:58 +0200	[thread overview]
Message-ID: <5029526E.7020605@gmail.com> (raw)
In-Reply-To: <5028FD7E.1010402@redhat.com>

Hi!

On 08/13/2012 03:13 PM, Hans de Goede wrote:
>> 2) If a driver supports only formats with more than one plane, should
>> V4L2_CAP_VIDEO_CAPTURE still be defined?
> 
> No

Agreed.

>> And if a driver also supports
>> single-plane formats in addition to >1 plane formats, should
>> V4L2_CAP_VIDEO_CAPTURE be compulsary?
> 
> Yes, so that non multi-plane aware apps keep working.

There is the multi-planar API and there are multi-planar formats. Single- 
and multi-planar formats can be handled with the multi-planar API. So if 
a driver supports single- and multi-planar formats by means on multi-planar
APIs, there shouldn't be a need for signalling V4L2_CAP_VIDEO_CAPTURE, 
which normally indicates single-planar API. The driver may choose to not 
support it, in order to handle single-planar formats. Thus, in my opinion 
making V4L2_CAP_VIDEO_CAPTURE compulsory wouldn't make sense. Unless the 
driver supports both types of ioctls (_mplane and regular versions), we 
shouldn't flag V4L2_CAP_VIDEO_CAPTURE. 

Regards,
Sylwester

  parent reply	other threads:[~2012-08-13 19:16 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-08-13 12:27 RFC: V4L2 API ambiguities Hans Verkuil
2012-08-13 13:13 ` [Workshop-2011] " Hans de Goede
2012-08-13 14:52   ` Hans Verkuil
2012-08-13 14:58     ` Hans de Goede
2012-08-13 15:09   ` Ilyes Gouta
2012-08-13 19:15   ` Sylwester Nawrocki [this message]
2012-08-14  8:13     ` Hans de Goede
2012-08-14  0:00   ` Laurent Pinchart
2012-08-14  8:15     ` Hans de Goede
2012-08-13 16:09 ` Rémi Denis-Courmont
2012-08-13 20:27 ` Walter Van Eetvelt
2012-08-13 21:31   ` Devin Heitmueller
2012-08-13 21:39     ` Mauro Carvalho Chehab
2012-08-13 21:42       ` Devin Heitmueller
2012-08-13 21:55         ` Mauro Carvalho Chehab
2012-08-13 23:54 ` [Workshop-2011] " Laurent Pinchart
2012-08-14 10:54   ` Hans Verkuil
2012-08-14 11:06     ` Laurent Pinchart
2012-08-14 11:11       ` Hans Verkuil
2012-08-14 11:15         ` Laurent Pinchart
2012-08-14 11:32           ` Hans Verkuil
2012-08-14 11:42             ` Laurent Pinchart
2012-08-14 21:14               ` Guennadi Liakhovetski
2012-08-14 22:10                 ` Laurent Pinchart
2012-08-14 12:43     ` Hans de Goede
2012-08-14 12:44       ` Chinmay V S

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=5029526E.7020605@gmail.com \
    --to=sylvester.nawrocki@gmail.com \
    --cc=hdegoede@redhat.com \
    --cc=hverkuil@xs4all.nl \
    --cc=linux-media@vger.kernel.org \
    --cc=workshop-2011@linuxtv.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).