From: Hans Verkuil <hansverk@cisco.com>
To: Mauro Carvalho Chehab <mchehab@s-opensource.com>,
Linux Doc Mailing List <linux-doc@vger.kernel.org>,
Linux Media Mailing List <linux-media@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>,
Mauro Carvalho Chehab <mchehab@infradead.org>,
linux-kernel@vger.kernel.org, Jonathan Corbet <corbet@lwn.net>,
Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>,
Sakari Ailus <sakari.ailus@linux.intel.com>,
Hans Verkuil <hans.verkuil@cisco.com>
Subject: Re: [PATCH 2/3] media: videodev2: add a flag for vdev-centric devices
Date: Fri, 25 Aug 2017 11:44:27 +0200 [thread overview]
Message-ID: <4f771cfa-0e0d-3548-a363-6470b32a6634@cisco.com> (raw)
In-Reply-To: <8d504be517755ee9449a007b5f2de52738c2df63.1503653839.git.mchehab@s-opensource.com>
On 08/25/2017 11:40 AM, Mauro Carvalho Chehab wrote:
> From: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
>
> As both vdev-centric and mc-centric devices may implement the
> same APIs, we need a flag to allow userspace to distinguish
> between them.
>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
> ---
> Documentation/media/uapi/v4l/open.rst | 6 ++++++
> Documentation/media/uapi/v4l/vidioc-querycap.rst | 4 ++++
> include/uapi/linux/videodev2.h | 2 ++
> 3 files changed, 12 insertions(+)
>
> diff --git a/Documentation/media/uapi/v4l/open.rst b/Documentation/media/uapi/v4l/open.rst
> index a72d142897c0..eb3f0ec57edb 100644
> --- a/Documentation/media/uapi/v4l/open.rst
> +++ b/Documentation/media/uapi/v4l/open.rst
> @@ -33,6 +33,12 @@ For **vdev-centric** control, the device and their corresponding hardware
> pipelines are controlled via the **V4L2 device** node. They may optionally
> expose via the :ref:`media controller API <media_controller>`.
>
> +.. note::
> +
> + **vdev-centric** devices should report V4L2_VDEV_CENTERED
You mean CENTRIC, not CENTERED.
But I would change this to MC_CENTRIC: the vast majority of drivers are VDEV centric,
so it makes a lot more sense to keep that as the default and only set the cap for
MC-centric drivers.
Regards,
Hans
> + :c:type:`v4l2_capability` flag (see :ref:`VIDIOC_QUERYCAP`).
> +
> +
> For **MC-centric** control, before using the V4L2 device, it is required to
> set the hardware pipelines via the
> :ref:`media controller API <media_controller>`. For those devices, the
> diff --git a/Documentation/media/uapi/v4l/vidioc-querycap.rst b/Documentation/media/uapi/v4l/vidioc-querycap.rst
> index 12e0d9a63cd8..4856821b7608 100644
> --- a/Documentation/media/uapi/v4l/vidioc-querycap.rst
> +++ b/Documentation/media/uapi/v4l/vidioc-querycap.rst
> @@ -252,6 +252,10 @@ specification the ioctl returns an ``EINVAL`` error code.
> * - ``V4L2_CAP_TOUCH``
> - 0x10000000
> - This is a touch device.
> + * - ``V4L2_VDEV_CENTERED``
> + - 0x20000000
> + - This is controlled via V4L2 device nodes (radio, video, vbi,
> + sdr
> * - ``V4L2_CAP_DEVICE_CAPS``
> - 0x80000000
> - The driver fills the ``device_caps`` field. This capability can
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 45cf7359822c..d89090d99042 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -460,6 +460,8 @@ struct v4l2_capability {
>
> #define V4L2_CAP_TOUCH 0x10000000 /* Is a touch device */
>
> +#define V4L2_CAP_VDEV_CENTERED 0x20000000 /* V4L2 Device is controlled via V4L2 device devnode */
> +
> #define V4L2_CAP_DEVICE_CAPS 0x80000000 /* sets device capabilities field */
>
> /*
>
next prev parent reply other threads:[~2017-08-25 9:44 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-25 9:40 [PATCH 0/3] document types of hardware control for V4L2 Mauro Carvalho Chehab
2017-08-25 9:40 ` [PATCH 1/3] media: open.rst: document devnode-centric and mc-centric types Mauro Carvalho Chehab
2017-08-25 10:32 ` Hans Verkuil
2017-08-25 11:08 ` Sakari Ailus
2017-08-25 13:11 ` Laurent Pinchart
2017-08-25 13:38 ` Mauro Carvalho Chehab
2017-08-25 13:57 ` Laurent Pinchart
2017-08-25 14:02 ` Hans Verkuil
2017-08-25 9:40 ` [PATCH 2/3] media: videodev2: add a flag for vdev-centric devices Mauro Carvalho Chehab
2017-08-25 9:44 ` Hans Verkuil [this message]
2017-08-25 10:06 ` Mauro Carvalho Chehab
2017-08-25 10:13 ` Hans Verkuil
2017-08-25 10:35 ` Mauro Carvalho Chehab
2017-08-25 10:42 ` Hans Verkuil
2017-08-25 10:50 ` Mauro Carvalho Chehab
2017-08-25 10:56 ` Hans Verkuil
2017-08-25 11:15 ` Mauro Carvalho Chehab
2017-08-25 11:30 ` Mauro Carvalho Chehab
2017-08-25 11:35 ` Mauro Carvalho Chehab
2017-08-25 11:42 ` Hans Verkuil
2017-08-25 13:27 ` Laurent Pinchart
2017-08-25 9:40 ` [PATCH 3/3] media: add V4L2_CAP_VDEV_CENTERED flag on vdev-centric drivers Mauro Carvalho Chehab
2017-08-25 9:47 ` Lubomir Rintel
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=4f771cfa-0e0d-3548-a363-6470b32a6634@cisco.com \
--to=hansverk@cisco.com \
--cc=corbet@lwn.net \
--cc=hans.verkuil@cisco.com \
--cc=laurent.pinchart+renesas@ideasonboard.com \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=mchehab@infradead.org \
--cc=mchehab@osg.samsung.com \
--cc=mchehab@s-opensource.com \
--cc=sakari.ailus@linux.intel.com \
/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).