Re: [PATCHv17 01/34] Documentation: v4l: document request API

[Mauro Carvalho Chehab <mchehab+samsung@kernel.org>]

Em Tue, 14 Aug 2018 11:51:30 +0200
Hans Verkuil <hverkuil@xs4all.nl> escreveu:

> On 14/08/18 10:48, Mauro Carvalho Chehab wrote:
> > Em Tue, 14 Aug 2018 09:57:27 +0200
> > Hans Verkuil <hverkuil@xs4all.nl> escreveu:
> >   
> >> On 09/08/18 19:43, Mauro Carvalho Chehab wrote:  
> >>>> diff --git a/Documentation/media/uapi/v4l/vidioc-qbuf.rst b/Documentation/media/uapi/v4l/vidioc-qbuf.rst
> >>>> index 9e448a4aa3aa..0e415f2551b2 100644
> >>>> --- a/Documentation/media/uapi/v4l/vidioc-qbuf.rst
> >>>> +++ b/Documentation/media/uapi/v4l/vidioc-qbuf.rst
> >>>> @@ -65,7 +65,7 @@ To enqueue a :ref:`memory mapped <mmap>` buffer applications set the
> >>>>  with a pointer to this structure the driver sets the
> >>>>  ``V4L2_BUF_FLAG_MAPPED`` and ``V4L2_BUF_FLAG_QUEUED`` flags and clears
> >>>>  the ``V4L2_BUF_FLAG_DONE`` flag in the ``flags`` field, or it returns an
> >>>> -EINVAL error code.
> >>>> +``EINVAL`` error code.    
> >>>
> >>> Side note: we should likely do a similar replacement on all other places
> >>> inside the media uAPI docs.
> >>>     
> >>>>  
> >>>>  To enqueue a :ref:`user pointer <userp>` buffer applications set the
> >>>>  ``memory`` field to ``V4L2_MEMORY_USERPTR``, the ``m.userptr`` field to
> >>>> @@ -98,6 +98,25 @@ dequeued, until the :ref:`VIDIOC_STREAMOFF <VIDIOC_STREAMON>` or
> >>>>  :ref:`VIDIOC_REQBUFS` ioctl is called, or until the
> >>>>  device is closed.
> >>>>  
> >>>> +The ``request_fd`` field can be used with the ``VIDIOC_QBUF`` ioctl to specify    
> >>>
> >>> Please prefer using :ref: for QBUF too, e. g.: 
> >>> 	:ref:`ioctl VIDIOC_QBUF <VIDIOC_QBUF>`    
> >>
> >> Does this make sense when you are in the QBUF documentation itself? Using :ref: will
> >> just link back to the same page.
> >>
> >> We need some guidelines here. I personally don't think this makes sense.  
> > 
> > I'm almost sure we're doing the same on every other place within media docs.  
> 
> Not in vidioc-qbuf.rst: there you never use :ref: to refer to a QBUF/DQBUF.
> I want to keep this as-is. If we really want to change this, then it should
> be done for all vidioc-*.rst files.
> 
> A quick grep shows that this is very common:
> 
> git grep '``VIDIOC_' Documentation/media/uapi/v4l/vidioc-*
> 
> I honestly think it is silly and even confusing to use a :ref: to the page
> you are already on.
> 
> I keep this as-is since this is consistent with the usage elsewhere in vidioc-qbuuf.rst.
> If we want to change this, then that's something we should do separately from this
> patch.

Ok, let's be consistent with what's already there.

Thanks,
Mauro