Re: [PATCH v10 3/4] media: docs: add glossary.rst with common terms used at V4L2 spec
From: Sakari Ailus <sakari.ailus@iki.fi>
Date: 2020-08-28 10:50:51
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Hi Mauro, On Fri, Aug 28, 2020 at 11:11:00AM +0200, Mauro Carvalho Chehab wrote:
quoted hunk ↗ jump to hunk
Em Thu, 27 Aug 2020 14:08:11 +0300 Sakari Ailus [off-list ref] escreveu:quoted
quoted
+ MC-centric + :term:`V4L2 hardware` that requires a :term:`MC API`. + + Such hardware have ``V4L2_CAP_IO_MC`` device_caps field set + (see :ref:`VIDIOC_QUERYCAP`). + + See :ref:`v4l2_hardware_control` for more details.I think this should be documented as referring to drivers, for it's a property of a driver, not hardware. There is hardware that better fits for MC-enabled drivers but still has V4L2-centric driver written for it. The matter is further complicated by e.g. raw camera systems that may consist of several different kinds of devices, including external ISPs. Say, a simple raw sensor + a CSI-2 receiver would fit for V4L2-centric model well, but add a more complex sensor or that external ISP and that no longer is the case. The CSI-2 receiver is still the same in both cases though. Similar comment on video-node-centric.I guess I got what you meant. I'm folding it with the following diff:diff --git a/Documentation/userspace-api/media/glossary.rst b/Documentation/userspace-api/media/glossary.rst index 45f0933e03c0..023bb561c406 100644 --- a/Documentation/userspace-api/media/glossary.rst +++ b/Documentation/userspace-api/media/glossary.rst@@ -138,9 +138,9 @@ Glossary See :ref:`media_controller`. MC-centric - :term:`V4L2 hardware` that requires a :term:`MC API`. + :term:`V4L2 hardware` device driver that requires :term:`MC API`. - Such hardware have ``V4L2_CAP_IO_MC`` device_caps field set + Such drivers have ``V4L2_CAP_IO_MC`` device_caps field set (see :ref:`VIDIOC_QUERYCAP`). See :ref:`v4l2_hardware_control` for more details.@@ -203,9 +203,9 @@ Glossary :term:`bridge driver`. See :ref:`subdev`. Video-node-centric - V4L2 hardware that doesn't require a media controller to be used. + V4L2 device driver that doesn't require a media controller to be used. - Such hardware have the ``V4L2_CAP_IO_MC`` device_caps field unset + Such drivers have the ``V4L2_CAP_IO_MC`` device_caps field unset (see :ref:`VIDIOC_QUERYCAP`). V4L2 Sub-device API
Yes, something like that. I also looked at a few more terms such as "V4L2 hardware" that are a bit of an oxymoron. This isn't in current documentation so we should give them a little bit more thought before adding them. I'll reply to the latest patch. -- Kind regards, Sakari Ailus