This short series convers device-drivers.tmpl into the RST format, splits
it up, and sets up the result under Documentation/driver-api/.  For added
fun, I've taken one top-level file (hsi.txt) and folded it into the
document as a way of showing the direction I'm thinking I would like things
to go.  There is plenty more of this sort of work that could be done, to
say the least - this is just a beginning!

The formatted results can be seen at:

    http://static.lwn.net/kerneldoc/driver-api/index.html

As part of the long-term task to turn Documentation/ into less of a horror
movie, I'd like to collect documentation of the driver-specific API here.
Arguably gpu/ and the media API stuff should eventually move here, though
we can discuss the color of that particular shed some other day.
Meanwhile, I'd appreciate comments on the general idea.

No need to be be, just be should be sufficient.
Signed-off-by: Laurent Navet <laurent.navet@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

So don't mention it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Handle signatures of function-like macros well. Don't try to deduce
arguments types of function-like macros.
Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The self.indexnode's tuple has changed in sphinx version 1.4, from a
former 4 element tuple to a 5 element tuple.

https://github.com/sphinx-doc/sphinx/commit/e6a5a3a92e938fcd75866b4227db9e0524d58f7cSigned-off-by: Markus Heiser <markus.heiser@darmarIT.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Fixed a -> an typo.
Signed-off-by: Robert Foss <robert.foss@collabora.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This is the driver API document, so the internal stuff is just noise here.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

It never made sense to keep these documents together; move each into its
own file.

Drop the section numbering on hsi.txt on its way to its own file.
Suggested-by: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The HSI subsystem documentation was split across hsi.txt and the
device-drivers docbook.  Now that the latter has been converted to Sphinx,
pull in the HSI document so that it's all in one place.
Acked-by: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add yet another regex to kernel-doc to trap @param() references separately
and not produce corrupt RST markup.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

As far as I can tell, the handling of "..." arguments has never worked
right, so any documentation provided was ignored in favor of "variable
arguments."  This makes kernel-doc handle "@...:" as documented.  It does
*not* fix spots in kerneldoc comments that don't follow that convention,
but they are no more broken than before.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This is a trivial fix to correct upper bound addresses to always be
inclusive. Previously, the majority of ranges specified were inclusive with a
small minority specifying an exclusive upper bound. This patch fixes this
inconsistency.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The driver that used the 'nodisconnect' parameter was removed in
commit 565bae6a ("[SCSI] 53c7xx: kill driver"). Related documentation
was cleaned up in commit f37a7238 ("[SCSI] 53c7xx: fix removal
fallout"), except for the remaining two mentions that are removed here.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

- The guide currently says to pad the structure to a multiple of
  64-bits. This is not necessary in cases where the structure contains
  no 64-bit types. Clarify this concept to avoid unnecessary padding.
- When using __u64 to hold user pointers, blindly trying to do a cast to
  a void __user * may generate a warning on 32-bit systems about a cast
  from an integer to a pointer of different size. There is a macro to
  deal with this which hides an ugly double cast. Add a reference to
  this macro.
Signed-off-by: Laura Abbott <labbott@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

To build only the PDF of the media folder run::

  make SPHINXDIRS=media pdfdocs
Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This extends the method to build only sub-folders to the targets
"latexdocs" and "pdfdocs". To do so, a conf.py in the sub-folder is
required, where the latex_documents of the sub-folder are
defined. E.g. to build only gpu's PDF add the following to the
Documentation/gpu/conf.py::

  +latex_documents = [
  +    ("index", "gpu.tex", "Linux GPU Driver Developer's Guide",
  +     "The kernel development community", "manual"),
  +]

and run:

  make SPHINXDIRS=gpu pdfdocs
Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The setup() function of a Sphinx-extension can return a dictionary. This
is treated by Sphinx as metadata of the extension [1].

With metadata "parallel_read_safe = True" a extension is marked as
save for "parallel reading of source". This is needed if you want
build in parallel with N processes. E.g.:

  make SPHINXOPTS=-j4 htmldocs

will no longer log warnings like:

  WARNING: the foobar extension does not declare if it is safe for
  parallel reading, assuming it isn't - please ask the extension author
  to check and make it explicit.

Add metadata to extensions:

* kernel-doc
* flat-table
* kernel-include

[1] http://www.sphinx-doc.org/en/stable/extdev/#extension-metadataSigned-off-by: Markus Heiser <markus.heiser@darmarIT.de>
Tested-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

When using a typedef function like this one:
	typedef bool v4l2_check_dv_timings_fnc (const struct v4l2_dv_timings * t, void * handle);

The Sphinx C domain expects it to create a c:type: reference,
as that's the way it creates the type references when parsing
a c:function:: declaration.

So, a declaration like:

	.. c:function:: bool v4l2_valid_dv_timings (const struct v4l2_dv_timings * t, const struct v4l2_dv_timings_cap * cap, v4l2_check_dv_timings_fnc fnc, void * fnc_handle)

Will create a cross reference for :c:type:`v4l2_check_dv_timings_fnc`.

So, when outputting such typedefs in RST format, we need to handle
this special case, as otherwise it will produce those warnings:

	./include/media/v4l2-dv-timings.h:43: WARNING: c:type reference target not found: v4l2_check_dv_timings_fnc
	./include/media/v4l2-dv-timings.h:60: WARNING: c:type reference target not found: v4l2_check_dv_timings_fnc
	./include/media/v4l2-dv-timings.h:81: WARNING: c:type reference target not found: v4l2_check_dv_timings_fnc

So, change the kernel-doc script to produce a RST output for the
above typedef as:
	.. c:type:: v4l2_check_dv_timings_fnc

	   **Typedef**: timings check callback

	**Syntax**

	  ``bool v4l2_check_dv_timings_fnc (const struct v4l2_dv_timings * t, void * handle);``
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Improve the parser to handle typedefs like:

	typedef bool v4l2_check_dv_timings_fnc(const struct v4l2_dv_timings *t, void *handle);
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

From the old description people still can't get what's the exact
difference between nr_cpus and maxcpus. Especially in kdump kernel
nr_cpus is always suggested if it's implemented in the ARCH. The
reason is nr_cpus is used to limit the max number of possible cpu
in system, the sum of already plugged cpus and hot plug cpus can't
exceed its value. However maxcpus is used to limit how many cpus
are allowed to be brought up during bootup.
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Right now, for a struct, kernel-doc produces the following output:

	.. c:type:: struct v4l2_prio_state

	   stores the priority states

	**Definition**

	::

	  struct v4l2_prio_state {
	    atomic_t prios[4];
	  };

	**Members**

	``atomic_t prios[4]``
	  array with elements to store the array priorities

Putting a member name in verbatim and adding a continuation line
causes the LaTeX output to generate something like:
	item[atomic_t prios\[4\]] array with elements to store the array priorities

Everything inside "item" is non-breakable, with may produce
lines bigger than the column width.

Also, for function members, like:

        int (* rx_read) (struct v4l2_subdev *sd, u8 *buf, size_t count,ssize_t *num);

It puts the name of the member at the end, like:

        int (*) (struct v4l2_subdev *sd, u8 *buf, size_t count,ssize_t *num) read

With is very confusing.

The best is to highlight what really matters: the member name.
is a secondary information.

So, change kernel-doc, for it to produce the output on a different way:

	**Members**

	``prios[4]``

	  array with elements to store the array priorities

Also, as the type is not part of LaTeX "item[]", LaTeX will split it into
multiple lines, if needed.

So, both LaTeX/PDF and HTML outputs will look good.

It should be noticed, however, that the way Sphinx LaTeX output handles
things like:

	Foo
	   bar

is different than the HTML output. On HTML, it will produce something
like:

	**Foo**
	   bar

While, on LaTeX, it puts both foo and bar at the same line, like:

	**Foo** bar
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

We need adjustbox to allow adjusting the size of tables that
are bigger than the line width. There are quite a few of them
at the media books.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

When XeLaTeX is in interactive mode, it complains that
py@noticelength already exists. Rename it and declare it
only once to avoid such messages.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Instead of painting the box with gray, let's use a colored
box. IMHO, that makes easier to warn users about some issue
pointed by the Sphinx. It also matches to what we do already
with the HTML output.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

While the current implementation works well when using as a
paragraph, it doesn't work properly if inside a table. As we
have quite a few such cases, fix the logic to take the column
size into account.

PS.: I took the logic there from the latest version of Sphinx.sty
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Sphinx supports LaTeX output. Sometimes, it is interesting to
call it directly, instead of also generating a PDF. As it comes
for free, add a target for it.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This is only one example, demonstrating the benefits of the patch
series.  The CEC_DQEVENT ioctl is migrated to the sphinx c-domain and
referred by ":name: CEC_DQEVENT".

With this change the indirection using ":ref:`CEC_DQEVENT` is no longer
needed, we can refer the ioctl directly with ":c:func:`CEC_DQEVENT`". As
addition in the index, there is a entry "CEC_DQEVENT (C function)".
Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This reverts commit a88b1672.

From the origin comit log::

  The RST cpp:function handler is very pedantic: it doesn't allow any
  macros like __user on it

Since the kernel-doc parser does NOT make use of the cpp:domain, there
is no need to change the kernel-doc parser eleminating the address_space
tags.
Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Moved the *duplicate C object description* warnings for function
declarations in the nitpicky mode. In nitpick mode, you can suppress
those warnings (e.g. ioctl) with::

  nitpicky = True
  nitpick_ignore = [
      ("c:func", "ioctl"),
  ]

See Sphinx documentation for the config values for ``nitpick`` and
``nitpick_ignore`` [1].

With this change all the ".. cpp:function:: int ioctl(..)" descriptions
(found in the media book) can be migrated to ".. c:function:: int
ioctl(..)", without getting any warnings. E.g.::

  .. cpp:function:: int ioctl( int fd, int request, struct cec_event *argp )

  .. c:function:: int ioctl( int fd, int request, struct cec_event *argp )

The main effect, is that we get those *CPP-types* back into Sphinx's C-
namespace and we need no longer to distinguish between c/cpp references,
when we refer a function like the ioctl.

[1] http://www.sphinx-doc.org/en/stable/config.html?highlight=nitpick#confval-nitpickySigned-off-by: Markus Heiser <markus.heiser@darmarIT.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add option 'name' to the "c:function:" directive.  With option 'name'
the ref-name of a function can be modified. E.g.::

    .. c:function:: int ioctl( int fd, int request )
       :name: VIDIOC_LOG_STATUS

The func-name (e.g. ioctl) remains in the output but the ref-name
changed from ``ioctl`` to ``VIDIOC_LOG_STATUS``. The index entry for
this function is also changed to ``VIDIOC_LOG_STATUS`` and the function
can now referenced by::

    :c:func:`VIDIOC_LOG_STATUS`
Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Add a sphinx-extension to customize the sphinx c-domain.  No functional
changes right yet, just the boilerplate code.
Signed-off-by: Markus Heiser <markus.heiser@darmarIT.de>
[ jc: coding-style tweak ]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

We don't need to keep it as a single large file anymore; split it up so
that it is easier to manage and the individual sections can be read
directly as plain files.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Perform a basic sphinx conversion of the device-drivers docbook and move it
to its own directory.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Coalesce development-tool documents into a single directory and sphinxify
them.

Acked-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>