From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from aer-iport-1.cisco.com ([173.38.203.51]:7227 "EHLO aer-iport-1.cisco.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755549AbdHYJoa (ORCPT ); Fri, 25 Aug 2017 05:44:30 -0400 Subject: Re: [PATCH 2/3] media: videodev2: add a flag for vdev-centric devices To: Mauro Carvalho Chehab , Linux Doc Mailing List , Linux Media Mailing List Cc: Mauro Carvalho Chehab , Mauro Carvalho Chehab , linux-kernel@vger.kernel.org, Jonathan Corbet , Laurent Pinchart , Sakari Ailus , Hans Verkuil References: <8d504be517755ee9449a007b5f2de52738c2df63.1503653839.git.mchehab@s-opensource.com> From: Hans Verkuil Message-ID: <4f771cfa-0e0d-3548-a363-6470b32a6634@cisco.com> Date: Fri, 25 Aug 2017 11:44:27 +0200 MIME-Version: 1.0 In-Reply-To: <8d504be517755ee9449a007b5f2de52738c2df63.1503653839.git.mchehab@s-opensource.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: On 08/25/2017 11:40 AM, Mauro Carvalho Chehab wrote: > From: Mauro Carvalho Chehab > > 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 > Signed-off-by: Mauro Carvalho Chehab > --- > 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 `. > > +.. 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 `. 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 */ > > /* >