Merge branch 'mauro' into docs-mw

Mauro's work to include documentation from our Python modules.  His cover
letter follows:

This is an extended version of:
    https://lore.kernel.org/linux-doc/cover.1768488832.git.mchehab+huawei@kernel.org/

It basically adds everything we currently have inside libs/tool/python
to "tools" book inside documentation.

This version should be independent of the other series yet to be merged,
(including the jobserver one).

The vast amount of changes here are docstring cleanups and additions.
They mainly consists on:

- ensuring that every phrase will end with a period, making it uniform
  along all files;
- cleaning ups to better uniform docstrings;
- variable descriptions now use "#:" markup, as it allows autodoc to
  add them inside the documentation;
- added some missing docstrings;
- some new blank lines at comments to make ReST syntax parser happy;
- add a couple of sphinx markups (mainly, code blocks).

Most of those are minor changes, affecting only comments.

It also has one patch per libarary type, adding them to docs.

For kernel-doc, I did the cleanups first, as there is one code block
inside tools/lib/python/kdoc/latex_fonts.py that would cause a Sphinx
crash without such markups.

The series actually starts with 3 fixes:

- avoid "*" markups on indexes with deep> 3 to override text
- a variable rename to stop abusing doctree name
- don't rely on cwd to get Documentation/ location

patch 4 adds support to document scripts either at:
    - tools/
    - scripts/

patch 5 contains a CSS to better display autodoc html output.

For those who want to play with documentation, documenting a python
file is very simple. All it takes is to use:

    .. automodule:: lib.python.<dir+name>

Usually, we add a couple of control members to it to adjust
the desired documentation scope (add/remove members, showing class
inheritance, showing members that currently don't have
docstrings, etc). That's why we're using:

    .. automodule:: lib.python.kdoc.enrich_formatter
       :members:
       :show-inheritance:
       :undoc-members:

(and similar) inside tools/kdoc*.rst.

autodoc allows filtering in/out members, file docstrings, etc.

It also allows documenting just some members or functions with
directives like:

    ..autofunction:
    ..automember:

Sphinx also has a helper script to generate .rst files with
documentation:

    $ sphinx-apidoc -o foobar tools/lib/python/

which can be helpful to discover what should be documented,
although changes are needed to use what it produces.

1 files changed, 56 insertions, 39 deletions

diff --git a/tools/lib/python/kdoc/latex_fonts.py b/tools/lib/python/kdoc/latex_fonts.py
index 29317f8006ea..1d04cbda169f 100755
--- a/tools/lib/python/kdoc/latex_fonts.py
+++ b/tools/lib/python/kdoc/latex_fonts.py
@@ -5,12 +5,13 @@
 # Ported to Python by (c) Mauro Carvalho Chehab, 2025
 
 """
-Detect problematic Noto CJK variable fonts.
+Detect problematic Noto CJK variable fonts
+==========================================
 
-For "make pdfdocs", reports of build errors of translations.pdf started
-arriving early 2024 [1, 2].  It turned out that Fedora and openSUSE
-tumbleweed have started deploying variable-font [3] format of "Noto CJK"
-fonts [4, 5].  For PDF, a LaTeX package named xeCJK is used for CJK
+For ``make pdfdocs``, reports of build errors of translations.pdf started
+arriving early 2024 [1]_ [2]_.  It turned out that Fedora and openSUSE
+tumbleweed have started deploying variable-font [3]_ format of "Noto CJK"
+fonts [4]_ [5]_.  For PDF, a LaTeX package named xeCJK is used for CJK
 (Chinese, Japanese, Korean) pages.  xeCJK requires XeLaTeX/XeTeX, which
 does not (and likely never will) understand variable fonts for historical
 reasons.
@@ -25,68 +26,77 @@ This script is invoked from the error path of "make pdfdocs" and emits
 suggestions if variable-font files of "Noto CJK" fonts are in the list of
 fonts accessible from XeTeX.
 
-References:
-[1]: https://lore.kernel.org/r/8734tqsrt7.fsf@meer.lwn.net/
-[2]: https://lore.kernel.org/r/1708585803.600323099@f111.i.mail.ru/
-[3]: https://en.wikipedia.org/wiki/Variable_font
-[4]: https://fedoraproject.org/wiki/Changes/Noto_CJK_Variable_Fonts
-[5]: https://build.opensuse.org/request/show/1157217
+.. [1] https://lore.kernel.org/r/8734tqsrt7.fsf@meer.lwn.net/
+.. [2] https://lore.kernel.org/r/1708585803.600323099@f111.i.mail.ru/
+.. [3] https://en.wikipedia.org/wiki/Variable_font
+.. [4] https://fedoraproject.org/wiki/Changes/Noto_CJK_Variable_Fonts
+.. [5] https://build.opensuse.org/request/show/1157217
 
-#===========================================================================
 Workarounds for building translations.pdf
-#===========================================================================
+-----------------------------------------
 
 * Denylist "variable font" Noto CJK fonts.
+
   - Create $HOME/deny-vf/fontconfig/fonts.conf from template below, with
     tweaks if necessary.  Remove leading "".
+
   - Path of fontconfig/fonts.conf can be overridden by setting an env
     variable FONTS_CONF_DENY_VF.
 
-    * Template:
------------------------------------------------------------------
-<?xml version="1.0"?>
-<!DOCTYPE fontconfig SYSTEM "urn:fontconfig:fonts.dtd">
-<fontconfig>
-<!--
-  Ignore variable-font glob (not to break xetex)
--->
-    <selectfont>
-        <rejectfont>
-            <!--
-                for Fedora
-            -->
-            <glob>/usr/share/fonts/google-noto-*-cjk-vf-fonts</glob>
-            <!--
-                for openSUSE tumbleweed
-            -->
-            <glob>/usr/share/fonts/truetype/Noto*CJK*-VF.otf</glob>
-        </rejectfont>
-    </selectfont>
-</fontconfig>
------------------------------------------------------------------
+    * Template::
+
+        <?xml version="1.0"?>
+        <!DOCTYPE fontconfig SYSTEM "urn:fontconfig:fonts.dtd">
+        <fontconfig>
+        <!--
+        Ignore variable-font glob (not to break xetex)
+        -->
+            <selectfont>
+                <rejectfont>
+                    <!--
+                        for Fedora
+                    -->
+                    <glob>/usr/share/fonts/google-noto-*-cjk-vf-fonts</glob>
+                    <!--
+                        for openSUSE tumbleweed
+                    -->
+                    <glob>/usr/share/fonts/truetype/Noto*CJK*-VF.otf</glob>
+                </rejectfont>
+            </selectfont>
+        </fontconfig>
 
     The denylisting is activated for "make pdfdocs".
 
 * For skipping CJK pages in PDF
+
   - Uninstall texlive-xecjk.
     Denylisting is not needed in this case.
 
 * For printing CJK pages in PDF
+
   - Need non-variable "Noto CJK" fonts.
+
     * Fedora
+
       - google-noto-sans-cjk-fonts
       - google-noto-serif-cjk-fonts
+
     * openSUSE tumbleweed
+
       - Non-variable "Noto CJK" fonts are not available as distro packages
         as of April, 2024.  Fetch a set of font files from upstream Noto
         CJK Font released at:
+
           https://github.com/notofonts/noto-cjk/tree/main/Sans#super-otc
+
         and at:
+
           https://github.com/notofonts/noto-cjk/tree/main/Serif#super-otc
-        , then uncompress and deploy them.
+
+        then uncompress and deploy them.
       - Remember to update fontconfig cache by running fc-cache.
 
-!!! Caution !!!
+.. caution::
     Uninstalling "variable font" packages can be dangerous.
     They might be depended upon by other packages important for your work.
     Denylisting should be less invasive, as it is effective only while
@@ -115,10 +125,15 @@ class LatexFontChecker:
         self.re_cjk = re.compile(r"([^:]+):\s*Noto\s+(Sans|Sans Mono|Serif) CJK")
 
     def description(self):
+        """
+        Returns module description.
+        """
         return __doc__
 
     def get_noto_cjk_vf_fonts(self):
-        """Get Noto CJK fonts"""
+        """
+        Get Noto CJK fonts.
+        """
 
         cjk_fonts = set()
         cmd = ["fc-list", ":", "file", "family", "variable"]
@@ -143,7 +158,9 @@ class LatexFontChecker:
         return sorted(cjk_fonts)
 
     def check(self):
-        """Check for problems with CJK fonts"""
+        """
+        Check for problems with CJK fonts.
+        """
 
         fonts = textwrap.indent("\n".join(self.get_noto_cjk_vf_fonts()), "    ")
         if not fonts: