Merge tag 'docs-6.16' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "A moderately busy cycle for documentation this time around:

   - The most significant change is the replacement of the old
     kernel-doc script (a monstrous collection of Perl regexes that
     predates the Git era) with a Python reimplementation. That, too, is
     a horrifying collection of regexes, but in a much cleaner and more
     maintainable structure that integrates far better with the Sphinx
     build system.

     This change has been in linux-next for the full 6.15 cycle; the
     small number of problems that turned up have been addressed,
     seemingly to everybody's satisfaction. The Perl kernel-doc script
     remains in tree (as scripts/kernel-doc.pl) and can be used with a
     command-line option if need be. Unless some reason to keep it
     around materializes, it will probably go away in 6.17.

     Credit goes to Mauro Carvalho Chehab for doing all this work.

   - Some RTLA documentation updates

   - A handful of Chinese translations

   - The usual collection of typo fixes, general updates, etc"

* tag 'docs-6.16' of git://git.lwn.net/linux: (85 commits)
  Docs: doc-guide: update sphinx.rst Sphinx version number
  docs: doc-guide: clarify latest theme usage
  Documentation/scheduler: Fix typo in sched-stats domain field description
  scripts: kernel-doc: prevent a KeyError when checking output
  docs: kerneldoc.py: simplify exception handling logic
  MAINTAINERS: update linux-doc entry to cover new Python scripts
  docs: align with scripts/syscall.tbl migration
  Documentation: NTB: Fix typo
  Documentation: ioctl-number: Update table intro
  docs: conf.py: drop backward support for old Sphinx versions
  Docs: driver-api/basics: add kobject_event interfaces
  Docs: relay: editing cleanups
  docs: fix "incase" typo in coresight/panic.rst
  Fix spelling error for 'parallel'
  docs: admin-guide: fix typos in reporting-issues.rst
  docs: dmaengine: add explanation for DMA_ASYNC_TX capability
  Documentation: leds: improve readibility of multicolor doc
  docs: fix typo in firmware-related section
  docs: Makefile: Inherit PYTHONPYCACHEPREFIX setting as env variable
  Documentation: ioctl-number: Update outdated submission info
  ...

1 files changed, 1745 insertions, 0 deletions

diff --git a/scripts/lib/kdoc/kdoc_parser.py b/scripts/lib/kdoc/kdoc_parser.py
new file mode 100644
index 000000000000..062453eefc7a
--- /dev/null
+++ b/scripts/lib/kdoc/kdoc_parser.py
@@ -0,0 +1,1745 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+# Copyright(c) 2025: Mauro Carvalho Chehab <mchehab@kernel.org>.
+#
+# pylint: disable=C0301,C0302,R0904,R0912,R0913,R0914,R0915,R0917,R1702
+
+"""
+kdoc_parser
+===========
+
+Read a C language source or header FILE and extract embedded
+documentation comments
+"""
+
+import re
+from pprint import pformat
+
+from kdoc_re import NestedMatch, KernRe
+
+
+#
+# Regular expressions used to parse kernel-doc markups at KernelDoc class.
+#
+# Let's declare them in lowercase outside any class to make easier to
+# convert from the python script.
+#
+# As those are evaluated at the beginning, no need to cache them
+#
+
+# Allow whitespace at end of comment start.
+doc_start = KernRe(r'^/\*\*\s*$', cache=False)
+
+doc_end = KernRe(r'\*/', cache=False)
+doc_com = KernRe(r'\s*\*\s*', cache=False)
+doc_com_body = KernRe(r'\s*\* ?', cache=False)
+doc_decl = doc_com + KernRe(r'(\w+)', cache=False)
+
+# @params and a strictly limited set of supported section names
+# Specifically:
+#   Match @word:
+#         @...:
+#         @{section-name}:
+# while trying to not match literal block starts like "example::"
+#
+doc_sect = doc_com + \
+            KernRe(r'\s*(\@[.\w]+|\@\.\.\.|description|context|returns?|notes?|examples?)\s*:([^:].*)?$',
+                flags=re.I, cache=False)
+
+doc_content = doc_com_body + KernRe(r'(.*)', cache=False)
+doc_block = doc_com + KernRe(r'DOC:\s*(.*)?', cache=False)
+doc_inline_start = KernRe(r'^\s*/\*\*\s*$', cache=False)
+doc_inline_sect = KernRe(r'\s*\*\s*(@\s*[\w][\w\.]*\s*):(.*)', cache=False)
+doc_inline_end = KernRe(r'^\s*\*/\s*$', cache=False)
+doc_inline_oneline = KernRe(r'^\s*/\*\*\s*(@[\w\s]+):\s*(.*)\s*\*/\s*$', cache=False)
+attribute = KernRe(r"__attribute__\s*\(\([a-z0-9,_\*\s\(\)]*\)\)",
+               flags=re.I | re.S, cache=False)
+
+export_symbol = KernRe(r'^\s*EXPORT_SYMBOL(_GPL)?\s*\(\s*(\w+)\s*\)\s*', cache=False)
+export_symbol_ns = KernRe(r'^\s*EXPORT_SYMBOL_NS(_GPL)?\s*\(\s*(\w+)\s*,\s*"\S+"\)\s*', cache=False)
+
+type_param = KernRe(r"\@(\w*((\.\w+)|(->\w+))*(\.\.\.)?)", cache=False)
+
+class state:
+    """
+    State machine enums
+    """
+
+    # Parser states
+    NORMAL        = 0        # normal code
+    NAME          = 1        # looking for function name
+    BODY_MAYBE    = 2        # body - or maybe more description
+    BODY          = 3        # the body of the comment
+    BODY_WITH_BLANK_LINE = 4 # the body which has a blank line
+    PROTO         = 5        # scanning prototype
+    DOCBLOCK      = 6        # documentation block
+    INLINE        = 7        # gathering doc outside main block
+
+    name = [
+        "NORMAL",
+        "NAME",
+        "BODY_MAYBE",
+        "BODY",
+        "BODY_WITH_BLANK_LINE",
+        "PROTO",
+        "DOCBLOCK",
+        "INLINE",
+    ]
+
+    # Inline documentation state
+    INLINE_NA     = 0 # not applicable ($state != INLINE)
+    INLINE_NAME   = 1 # looking for member name (@foo:)
+    INLINE_TEXT   = 2 # looking for member documentation
+    INLINE_END    = 3 # done
+    INLINE_ERROR  = 4 # error - Comment without header was found.
+                      # Spit a warning as it's not
+                      # proper kernel-doc and ignore the rest.
+
+    inline_name = [
+        "",
+        "_NAME",
+        "_TEXT",
+        "_END",
+        "_ERROR",
+    ]
+
+SECTION_DEFAULT = "Description"  # default section
+
+class KernelEntry:
+
+    def __init__(self, config, ln):
+        self.config = config
+
+        self.contents = ""
+        self.function = ""
+        self.sectcheck = ""
+        self.struct_actual = ""
+        self.prototype = ""
+
+        self.warnings = []
+
+        self.parameterlist = []
+        self.parameterdescs = {}
+        self.parametertypes = {}
+        self.parameterdesc_start_lines = {}
+
+        self.section_start_lines = {}
+        self.sectionlist = []
+        self.sections = {}
+
+        self.anon_struct_union = False
+
+        self.leading_space = None
+
+        # State flags
+        self.brcount = 0
+
+        self.in_doc_sect = False
+        self.declaration_start_line = ln + 1
+
+    # TODO: rename to emit_message after removal of kernel-doc.pl
+    def emit_msg(self, log_msg, warning=True):
+        """Emit a message"""
+
+        if not warning:
+            self.config.log.info(log_msg)
+            return
+
+        # Delegate warning output to output logic, as this way it
+        # will report warnings/info only for symbols that are output
+
+        self.warnings.append(log_msg)
+        return
+
+    def dump_section(self, start_new=True):
+        """
+        Dumps section contents to arrays/hashes intended for that purpose.
+        """
+
+        name = self.section
+        contents = self.contents
+
+        if type_param.match(name):
+            name = type_param.group(1)
+
+            self.parameterdescs[name] = contents
+            self.parameterdesc_start_lines[name] = self.new_start_line
+
+            self.sectcheck += name + " "
+            self.new_start_line = 0
+
+        elif name == "@...":
+            name = "..."
+            self.parameterdescs[name] = contents
+            self.sectcheck += name + " "
+            self.parameterdesc_start_lines[name] = self.new_start_line
+            self.new_start_line = 0
+
+        else:
+            if name in self.sections and self.sections[name] != "":
+                # Only warn on user-specified duplicate section names
+                if name != SECTION_DEFAULT:
+                    self.emit_msg(self.new_start_line,
+                                  f"duplicate section name '{name}'\n")
+                self.sections[name] += contents
+            else:
+                self.sections[name] = contents
+                self.sectionlist.append(name)
+                self.section_start_lines[name] = self.new_start_line
+                self.new_start_line = 0
+
+#        self.config.log.debug("Section: %s : %s", name, pformat(vars(self)))
+
+        if start_new:
+            self.section = SECTION_DEFAULT
+            self.contents = ""
+
+
+class KernelDoc:
+    """
+    Read a C language source or header FILE and extract embedded
+    documentation comments.
+    """
+
+    # Section names
+
+    section_intro = "Introduction"
+    section_context = "Context"
+    section_return = "Return"
+
+    undescribed = "-- undescribed --"
+
+    def __init__(self, config, fname):
+        """Initialize internal variables"""
+
+        self.fname = fname
+        self.config = config
+
+        # Initial state for the state machines
+        self.state = state.NORMAL
+        self.inline_doc_state = state.INLINE_NA
+
+        # Store entry currently being processed
+        self.entry = None
+
+        # Place all potential outputs into an array
+        self.entries = []
+
+    def emit_msg(self, ln, msg, warning=True):
+        """Emit a message"""
+
+        log_msg = f"{self.fname}:{ln} {msg}"
+
+        if self.entry:
+            self.entry.emit_msg(log_msg, warning)
+            return
+
+        if warning:
+            self.config.log.warning(log_msg)
+        else:
+            self.config.log.info(log_msg)
+
+    def dump_section(self, start_new=True):
+        """
+        Dumps section contents to arrays/hashes intended for that purpose.
+        """
+
+        if self.entry:
+            self.entry.dump_section(start_new)
+
+    # TODO: rename it to store_declaration after removal of kernel-doc.pl
+    def output_declaration(self, dtype, name, **args):
+        """
+        Stores the entry into an entry array.
+
+        The actual output and output filters will be handled elsewhere
+        """
+
+        # The implementation here is different than the original kernel-doc:
+        # instead of checking for output filters or actually output anything,
+        # it just stores the declaration content at self.entries, as the
+        # output will happen on a separate class.
+        #
+        # For now, we're keeping the same name of the function just to make
+        # easier to compare the source code of both scripts
+
+        args["declaration_start_line"] = self.entry.declaration_start_line
+        args["type"] = dtype
+        args["warnings"] = self.entry.warnings
+
+        # TODO: use colletions.OrderedDict to remove sectionlist
+
+        sections = args.get('sections', {})
+        sectionlist = args.get('sectionlist', [])
+
+        # Drop empty sections
+        # TODO: improve empty sections logic to emit warnings
+        for section in ["Description", "Return"]:
+            if section in sectionlist:
+                if not sections[section].rstrip():
+                    del sections[section]
+                    sectionlist.remove(section)
+
+        self.entries.append((name, args))
+
+        self.config.log.debug("Output: %s:%s = %s", dtype, name, pformat(args))
+
+    def reset_state(self, ln):
+        """
+        Ancillary routine to create a new entry. It initializes all
+        variables used by the state machine.
+        """
+
+        self.entry = KernelEntry(self.config, ln)
+
+        # State flags
+        self.state = state.NORMAL
+        self.inline_doc_state = state.INLINE_NA
+
+    def push_parameter(self, ln, decl_type, param, dtype,
+                       org_arg, declaration_name):
+        """
+        Store parameters and their descriptions at self.entry.
+        """
+
+        if self.entry.anon_struct_union and dtype == "" and param == "}":
+            return  # Ignore the ending }; from anonymous struct/union
+
+        self.entry.anon_struct_union = False
+
+        param = KernRe(r'[\[\)].*').sub('', param, count=1)
+
+        if dtype == "" and param.endswith("..."):
+            if KernRe(r'\w\.\.\.$').search(param):
+                # For named variable parameters of the form `x...`,
+                # remove the dots
+                param = param[:-3]
+            else:
+                # Handles unnamed variable parameters
+                param = "..."
+
+            if param not in self.entry.parameterdescs or \
+                not self.entry.parameterdescs[param]:
+
+                self.entry.parameterdescs[param] = "variable arguments"
+
+        elif dtype == "" and (not param or param == "void"):
+            param = "void"
+            self.entry.parameterdescs[param] = "no arguments"
+
+        elif dtype == "" and param in ["struct", "union"]:
+            # Handle unnamed (anonymous) union or struct
+            dtype = param
+            param = "{unnamed_" + param + "}"
+            self.entry.parameterdescs[param] = "anonymous\n"
+            self.entry.anon_struct_union = True
+
+        # Handle cache group enforcing variables: they do not need
+        # to be described in header files
+        elif "__cacheline_group" in param:
+            # Ignore __cacheline_group_begin and __cacheline_group_end
+            return
+
+        # Warn if parameter has no description
+        # (but ignore ones starting with # as these are not parameters
+        # but inline preprocessor statements)
+        if param not in self.entry.parameterdescs and not param.startswith("#"):
+            self.entry.parameterdescs[param] = self.undescribed
+
+            if "." not in param:
+                if decl_type == 'function':
+                    dname = f"{decl_type} parameter"
+                else:
+                    dname = f"{decl_type} member"
+
+                self.emit_msg(ln,
+                              f"{dname} '{param}' not described in '{declaration_name}'")
+
+        # Strip spaces from param so that it is one continuous string on
+        # parameterlist. This fixes a problem where check_sections()
+        # cannot find a parameter like "addr[6 + 2]" because it actually
+        # appears as "addr[6", "+", "2]" on the parameter list.
+        # However, it's better to maintain the param string unchanged for
+        # output, so just weaken the string compare in check_sections()
+        # to ignore "[blah" in a parameter string.
+
+        self.entry.parameterlist.append(param)
+        org_arg = KernRe(r'\s\s+').sub(' ', org_arg)
+        self.entry.parametertypes[param] = org_arg
+
+    def save_struct_actual(self, actual):
+        """
+        Strip all spaces from the actual param so that it looks like
+        one string item.
+        """
+
+        actual = KernRe(r'\s*').sub("", actual, count=1)
+
+        self.entry.struct_actual += actual + " "
+
+    def create_parameter_list(self, ln, decl_type, args,
+                              splitter, declaration_name):
+        """
+        Creates a list of parameters, storing them at self.entry.
+        """
+
+        # temporarily replace all commas inside function pointer definition
+        arg_expr = KernRe(r'(\([^\),]+),')
+        while arg_expr.search(args):
+            args = arg_expr.sub(r"\1#", args)
+
+        for arg in args.split(splitter):
+            # Strip comments
+            arg = KernRe(r'\/\*.*\*\/').sub('', arg)
+
+            # Ignore argument attributes
+            arg = KernRe(r'\sPOS0?\s').sub(' ', arg)
+
+            # Strip leading/trailing spaces
+            arg = arg.strip()
+            arg = KernRe(r'\s+').sub(' ', arg, count=1)
+
+            if arg.startswith('#'):
+                # Treat preprocessor directive as a typeless variable just to fill
+                # corresponding data structures "correctly". Catch it later in
+                # output_* subs.
+
+                # Treat preprocessor directive as a typeless variable
+                self.push_parameter(ln, decl_type, arg, "",
+                                    "", declaration_name)
+
+            elif KernRe(r'\(.+\)\s*\(').search(arg):
+                # Pointer-to-function
+
+                arg = arg.replace('#', ',')
+
+                r = KernRe(r'[^\(]+\(\*?\s*([\w\[\]\.]*)\s*\)')
+                if r.match(arg):
+                    param = r.group(1)
+                else:
+                    self.emit_msg(ln, f"Invalid param: {arg}")
+                    param = arg
+
+                dtype = KernRe(r'([^\(]+\(\*?)\s*' + re.escape(param)).sub(r'\1', arg)
+                self.save_struct_actual(param)
+                self.push_parameter(ln, decl_type, param, dtype,
+                                    arg, declaration_name)
+
+            elif KernRe(r'\(.+\)\s*\[').search(arg):
+                # Array-of-pointers
+
+                arg = arg.replace('#', ',')
+                r = KernRe(r'[^\(]+\(\s*\*\s*([\w\[\]\.]*?)\s*(\s*\[\s*[\w]+\s*\]\s*)*\)')
+                if r.match(arg):
+                    param = r.group(1)
+                else:
+                    self.emit_msg(ln, f"Invalid param: {arg}")
+                    param = arg
+
+                dtype = KernRe(r'([^\(]+\(\*?)\s*' + re.escape(param)).sub(r'\1', arg)
+
+                self.save_struct_actual(param)
+                self.push_parameter(ln, decl_type, param, dtype,
+                                    arg, declaration_name)
+
+            elif arg:
+                arg = KernRe(r'\s*:\s*').sub(":", arg)
+                arg = KernRe(r'\s*\[').sub('[', arg)
+
+                args = KernRe(r'\s*,\s*').split(arg)
+                if args[0] and '*' in args[0]:
+                    args[0] = re.sub(r'(\*+)\s*', r' \1', args[0])
+
+                first_arg = []
+                r = KernRe(r'^(.*\s+)(.*?\[.*\].*)$')
+                if args[0] and r.match(args[0]):
+                    args.pop(0)
+                    first_arg.extend(r.group(1))
+                    first_arg.append(r.group(2))
+                else:
+                    first_arg = KernRe(r'\s+').split(args.pop(0))
+
+                args.insert(0, first_arg.pop())
+                dtype = ' '.join(first_arg)
+
+                for param in args:
+                    if KernRe(r'^(\*+)\s*(.*)').match(param):
+                        r = KernRe(r'^(\*+)\s*(.*)')
+                        if not r.match(param):
+                            self.emit_msg(ln, f"Invalid param: {param}")
+                            continue
+
+                        param = r.group(1)
+
+                        self.save_struct_actual(r.group(2))
+                        self.push_parameter(ln, decl_type, r.group(2),
+                                            f"{dtype} {r.group(1)}",
+                                            arg, declaration_name)
+
+                    elif KernRe(r'(.*?):(\w+)').search(param):
+                        r = KernRe(r'(.*?):(\w+)')
+                        if not r.match(param):
+                            self.emit_msg(ln, f"Invalid param: {param}")
+                            continue
+
+                        if dtype != "":  # Skip unnamed bit-fields
+                            self.save_struct_actual(r.group(1))
+                            self.push_parameter(ln, decl_type, r.group(1),
+                                                f"{dtype}:{r.group(2)}",
+                                                arg, declaration_name)
+                    else:
+                        self.save_struct_actual(param)
+                        self.push_parameter(ln, decl_type, param, dtype,
+                                            arg, declaration_name)
+
+    def check_sections(self, ln, decl_name, decl_type, sectcheck, prmscheck):
+        """
+        Check for errors inside sections, emitting warnings if not found
+        parameters are described.
+        """
+
+        sects = sectcheck.split()
+        prms = prmscheck.split()
+        err = False
+
+        for sx in range(len(sects)):                  # pylint: disable=C0200
+            err = True
+            for px in range(len(prms)):               # pylint: disable=C0200
+                prm_clean = prms[px]
+                prm_clean = KernRe(r'\[.*\]').sub('', prm_clean)
+                prm_clean = attribute.sub('', prm_clean)
+
+                # ignore array size in a parameter string;
+                # however, the original param string may contain
+                # spaces, e.g.:  addr[6 + 2]
+                # and this appears in @prms as "addr[6" since the
+                # parameter list is split at spaces;
+                # hence just ignore "[..." for the sections check;
+                prm_clean = KernRe(r'\[.*').sub('', prm_clean)
+
+                if prm_clean == sects[sx]:
+                    err = False
+                    break
+
+            if err:
+                if decl_type == 'function':
+                    dname = f"{decl_type} parameter"
+                else:
+                    dname = f"{decl_type} member"
+
+                self.emit_msg(ln,
+                              f"Excess {dname} '{sects[sx]}' description in '{decl_name}'")
+
+    def check_return_section(self, ln, declaration_name, return_type):
+        """
+        If the function doesn't return void, warns about the lack of a
+        return description.
+        """
+
+        if not self.config.wreturn:
+            return
+
+        # Ignore an empty return type (It's a macro)
+        # Ignore functions with a "void" return type (but not "void *")
+        if not return_type or KernRe(r'void\s*\w*\s*$').search(return_type):
+            return
+
+        if not self.entry.sections.get("Return", None):
+            self.emit_msg(ln,
+                          f"No description found for return value of '{declaration_name}'")
+
+    def dump_struct(self, ln, proto):
+        """
+        Store an entry for an struct or union
+        """
+
+        type_pattern = r'(struct|union)'
+
+        qualifiers = [
+            "__attribute__",
+            "__packed",
+            "__aligned",
+            "____cacheline_aligned_in_smp",
+            "____cacheline_aligned",
+        ]
+
+        definition_body = r'\{(.*)\}\s*' + "(?:" + '|'.join(qualifiers) + ")?"
+        struct_members = KernRe(type_pattern + r'([^\{\};]+)(\{)([^\{\}]*)(\})([^\{\}\;]*)(\;)')
+
+        # Extract struct/union definition
+        members = None
+        declaration_name = None
+        decl_type = None
+
+        r = KernRe(type_pattern + r'\s+(\w+)\s*' + definition_body)
+        if r.search(proto):
+            decl_type = r.group(1)
+            declaration_name = r.group(2)
+            members = r.group(3)
+        else:
+            r = KernRe(r'typedef\s+' + type_pattern + r'\s*' + definition_body + r'\s*(\w+)\s*;')
+
+            if r.search(proto):
+                decl_type = r.group(1)
+                declaration_name = r.group(3)
+                members = r.group(2)
+
+        if not members:
+            self.emit_msg(ln, f"{proto} error: Cannot parse struct or union!")
+            return
+
+        if self.entry.identifier != declaration_name:
+            self.emit_msg(ln,
+                          f"expecting prototype for {decl_type} {self.entry.identifier}. Prototype was for {decl_type} {declaration_name} instead\n")
+            return
+
+        args_pattern = r'([^,)]+)'
+
+        sub_prefixes = [
+            (KernRe(r'\/\*\s*private:.*?\/\*\s*public:.*?\*\/', re.S | re.I), ''),
+            (KernRe(r'\/\*\s*private:.*', re.S | re.I), ''),
+
+            # Strip comments
+            (KernRe(r'\/\*.*?\*\/', re.S), ''),
+
+            # Strip attributes
+            (attribute, ' '),
+            (KernRe(r'\s*__aligned\s*\([^;]*\)', re.S), ' '),
+            (KernRe(r'\s*__counted_by\s*\([^;]*\)', re.S), ' '),
+            (KernRe(r'\s*__counted_by_(le|be)\s*\([^;]*\)', re.S), ' '),
+            (KernRe(r'\s*__packed\s*', re.S), ' '),
+            (KernRe(r'\s*CRYPTO_MINALIGN_ATTR', re.S), ' '),
+            (KernRe(r'\s*____cacheline_aligned_in_smp', re.S), ' '),
+            (KernRe(r'\s*____cacheline_aligned', re.S), ' '),
+
+            # Unwrap struct_group macros based on this definition:
+            # __struct_group(TAG, NAME, ATTRS, MEMBERS...)
+            # which has variants like: struct_group(NAME, MEMBERS...)
+            # Only MEMBERS arguments require documentation.
+            #
+            # Parsing them happens on two steps:
+            #
+            # 1. drop struct group arguments that aren't at MEMBERS,
+            #    storing them as STRUCT_GROUP(MEMBERS)
+            #
+            # 2. remove STRUCT_GROUP() ancillary macro.
+            #
+            # The original logic used to remove STRUCT_GROUP() using an
+            # advanced regex:
+            #
+            #   \bSTRUCT_GROUP(\(((?:(?>[^)(]+)|(?1))*)\))[^;]*;
+            #
+            # with two patterns that are incompatible with
+            # Python re module, as it has:
+            #
+            #   - a recursive pattern: (?1)
+            #   - an atomic grouping: (?>...)
+            #
+            # I tried a simpler version: but it didn't work either:
+            #   \bSTRUCT_GROUP\(([^\)]+)\)[^;]*;
+            #
+            # As it doesn't properly match the end parenthesis on some cases.
+            #
+            # So, a better solution was crafted: there's now a NestedMatch
+            # class that ensures that delimiters after a search are properly
+            # matched. So, the implementation to drop STRUCT_GROUP() will be
+            # handled in separate.
+
+            (KernRe(r'\bstruct_group\s*\(([^,]*,)', re.S), r'STRUCT_GROUP('),
+            (KernRe(r'\bstruct_group_attr\s*\(([^,]*,){2}', re.S), r'STRUCT_GROUP('),
+            (KernRe(r'\bstruct_group_tagged\s*\(([^,]*),([^,]*),', re.S), r'struct \1 \2; STRUCT_GROUP('),
+            (KernRe(r'\b__struct_group\s*\(([^,]*,){3}', re.S), r'STRUCT_GROUP('),
+
+            # Replace macros
+            #
+            # TODO: use NestedMatch for FOO($1, $2, ...) matches
+            #
+            # it is better to also move those to the NestedMatch logic,
+            # to ensure that parenthesis will be properly matched.
+
+            (KernRe(r'__ETHTOOL_DECLARE_LINK_MODE_MASK\s*\(([^\)]+)\)', re.S), r'DECLARE_BITMAP(\1, __ETHTOOL_LINK_MODE_MASK_NBITS)'),
+            (KernRe(r'DECLARE_PHY_INTERFACE_MASK\s*\(([^\)]+)\)', re.S), r'DECLARE_BITMAP(\1, PHY_INTERFACE_MODE_MAX)'),
+            (KernRe(r'DECLARE_BITMAP\s*\(' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'unsigned long \1[BITS_TO_LONGS(\2)]'),
+            (KernRe(r'DECLARE_HASHTABLE\s*\(' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'unsigned long \1[1 << ((\2) - 1)]'),
+            (KernRe(r'DECLARE_KFIFO\s*\(' + args_pattern + r',\s*' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'\2 *\1'),
+            (KernRe(r'DECLARE_KFIFO_PTR\s*\(' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'\2 *\1'),
+            (KernRe(r'(?:__)?DECLARE_FLEX_ARRAY\s*\(' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'\1 \2[]'),
+            (KernRe(r'DEFINE_DMA_UNMAP_ADDR\s*\(' + args_pattern + r'\)', re.S), r'dma_addr_t \1'),
+            (KernRe(r'DEFINE_DMA_UNMAP_LEN\s*\(' + args_pattern + r'\)', re.S), r'__u32 \1'),
+        ]
+
+        # Regexes here are guaranteed to have the end limiter matching
+        # the start delimiter. Yet, right now, only one replace group
+        # is allowed.
+
+        sub_nested_prefixes = [
+            (re.compile(r'\bSTRUCT_GROUP\('), r'\1'),
+        ]
+
+        for search, sub in sub_prefixes:
+            members = search.sub(sub, members)
+
+        nested = NestedMatch()
+
+        for search, sub in sub_nested_prefixes:
+            members = nested.sub(search, sub, members)
+
+        # Keeps the original declaration as-is
+        declaration = members
+
+        # Split nested struct/union elements
+        #
+        # This loop was simpler at the original kernel-doc perl version, as
+        #   while ($members =~ m/$struct_members/) { ... }
+        # reads 'members' string on each interaction.
+        #
+        # Python behavior is different: it parses 'members' only once,
+        # creating a list of tuples from the first interaction.
+        #
+        # On other words, this won't get nested structs.
+        #
+        # So, we need to have an extra loop on Python to override such
+        # re limitation.
+
+        while True:
+            tuples = struct_members.findall(members)
+            if not tuples:
+                break
+
+            for t in tuples:
+                newmember = ""
+                maintype = t[0]
+                s_ids = t[5]
+                content = t[3]
+
+                oldmember = "".join(t)
+
+                for s_id in s_ids.split(','):
+                    s_id = s_id.strip()
+
+                    newmember += f"{maintype} {s_id}; "
+                    s_id = KernRe(r'[:\[].*').sub('', s_id)
+                    s_id = KernRe(r'^\s*\**(\S+)\s*').sub(r'\1', s_id)
+
+                    for arg in content.split(';'):
+                        arg = arg.strip()
+
+                        if not arg:
+                            continue
+
+                        r = KernRe(r'^([^\(]+\(\*?\s*)([\w\.]*)(\s*\).*)')
+                        if r.match(arg):
+                            # Pointer-to-function
+                            dtype = r.group(1)
+                            name = r.group(2)
+                            extra = r.group(3)
+
+                            if not name:
+                                continue
+
+                            if not s_id:
+                                # Anonymous struct/union
+                                newmember += f"{dtype}{name}{extra}; "
+                            else:
+                                newmember += f"{dtype}{s_id}.{name}{extra}; "
+
+                        else:
+                            arg = arg.strip()
+                            # Handle bitmaps
+                            arg = KernRe(r':\s*\d+\s*').sub('', arg)
+
+                            # Handle arrays
+                            arg = KernRe(r'\[.*\]').sub('', arg)
+
+                            # Handle multiple IDs
+                            arg = KernRe(r'\s*,\s*').sub(',', arg)
+
+                            r = KernRe(r'(.*)\s+([\S+,]+)')
+
+                            if r.search(arg):
+                                dtype = r.group(1)
+                                names = r.group(2)
+                            else:
+                                newmember += f"{arg}; "
+                                continue
+
+                            for name in names.split(','):
+                                name = KernRe(r'^\s*\**(\S+)\s*').sub(r'\1', name).strip()
+
+                                if not name:
+                                    continue
+
+                                if not s_id:
+                                    # Anonymous struct/union
+                                    newmember += f"{dtype} {name}; "
+                                else:
+                                    newmember += f"{dtype} {s_id}.{name}; "
+
+                members = members.replace(oldmember, newmember)
+
+        # Ignore other nested elements, like enums
+        members = re.sub(r'(\{[^\{\}]*\})', '', members)
+
+        self.create_parameter_list(ln, decl_type, members, ';',
+                                   declaration_name)
+        self.check_sections(ln, declaration_name, decl_type,
+                            self.entry.sectcheck, self.entry.struct_actual)
+
+        # Adjust declaration for better display
+        declaration = KernRe(r'([\{;])').sub(r'\1\n', declaration)
+        declaration = KernRe(r'\}\s+;').sub('};', declaration)
+
+        # Better handle inlined enums
+        while True:
+            r = KernRe(r'(enum\s+\{[^\}]+),([^\n])')
+            if not r.search(declaration):
+                break
+
+            declaration = r.sub(r'\1,\n\2', declaration)
+
+        def_args = declaration.split('\n')
+        level = 1
+        declaration = ""
+        for clause in def_args:
+
+            clause = clause.strip()
+            clause = KernRe(r'\s+').sub(' ', clause, count=1)
+
+            if not clause:
+                continue
+
+            if '}' in clause and level > 1:
+                level -= 1
+
+            if not KernRe(r'^\s*#').match(clause):
+                declaration += "\t" * level
+
+            declaration += "\t" + clause + "\n"
+            if "{" in clause and "}" not in clause:
+                level += 1
+
+        self.output_declaration(decl_type, declaration_name,
+                                struct=declaration_name,
+                                definition=declaration,
+                                parameterlist=self.entry.parameterlist,
+                                parameterdescs=self.entry.parameterdescs,
+                                parametertypes=self.entry.parametertypes,
+                                parameterdesc_start_lines=self.entry.parameterdesc_start_lines,
+                                sectionlist=self.entry.sectionlist,
+                                sections=self.entry.sections,
+                                section_start_lines=self.entry.section_start_lines,
+                                purpose=self.entry.declaration_purpose)
+
+    def dump_enum(self, ln, proto):
+        """
+        Stores an enum inside self.entries array.
+        """
+
+        # Ignore members marked private
+        proto = KernRe(r'\/\*\s*private:.*?\/\*\s*public:.*?\*\/', flags=re.S).sub('', proto)
+        proto = KernRe(r'\/\*\s*private:.*}', flags=re.S).sub('}', proto)
+
+        # Strip comments
+        proto = KernRe(r'\/\*.*?\*\/', flags=re.S).sub('', proto)
+
+        # Strip #define macros inside enums
+        proto = KernRe(r'#\s*((define|ifdef|if)\s+|endif)[^;]*;', flags=re.S).sub('', proto)
+
+        members = None
+        declaration_name = None
+
+        r = KernRe(r'typedef\s+enum\s*\{(.*)\}\s*(\w*)\s*;')
+        if r.search(proto):
+            declaration_name = r.group(2)
+            members = r.group(1).rstrip()
+        else:
+            r = KernRe(r'enum\s+(\w*)\s*\{(.*)\}')
+            if r.match(proto):
+                declaration_name = r.group(1)
+                members = r.group(2).rstrip()
+
+        if not members:
+            self.emit_msg(ln, f"{proto}: error: Cannot parse enum!")
+            return
+
+        if self.entry.identifier != declaration_name:
+            if self.entry.identifier == "":
+                self.emit_msg(ln,
+                              f"{proto}: wrong kernel-doc identifier on prototype")
+            else:
+                self.emit_msg(ln,
+                              f"expecting prototype for enum {self.entry.identifier}. Prototype was for enum {declaration_name} instead")
+            return
+
+        if not declaration_name:
+            declaration_name = "(anonymous)"
+
+        member_set = set()
+
+        members = KernRe(r'\([^;]*?[\)]').sub('', members)
+
+        for arg in members.split(','):
+            if not arg:
+                continue
+            arg = KernRe(r'^\s*(\w+).*').sub(r'\1', arg)
+            self.entry.parameterlist.append(arg)
+            if arg not in self.entry.parameterdescs:
+                self.entry.parameterdescs[arg] = self.undescribed
+                self.emit_msg(ln,
+                              f"Enum value '{arg}' not described in enum '{declaration_name}'")
+            member_set.add(arg)
+
+        for k in self.entry.parameterdescs:
+            if k not in member_set:
+                self.emit_msg(ln,
+                              f"Excess enum value '%{k}' description in '{declaration_name}'")
+
+        self.output_declaration('enum', declaration_name,
+                                enum=declaration_name,
+                                parameterlist=self.entry.parameterlist,
+                                parameterdescs=self.entry.parameterdescs,
+                                parameterdesc_start_lines=self.entry.parameterdesc_start_lines,
+                                sectionlist=self.entry.sectionlist,
+                                sections=self.entry.sections,
+                                section_start_lines=self.entry.section_start_lines,
+                                purpose=self.entry.declaration_purpose)
+
+    def dump_declaration(self, ln, prototype):
+        """
+        Stores a data declaration inside self.entries array.
+        """
+
+        if self.entry.decl_type == "enum":
+            self.dump_enum(ln, prototype)
+            return
+
+        if self.entry.decl_type == "typedef":
+            self.dump_typedef(ln, prototype)
+            return
+
+        if self.entry.decl_type in ["union", "struct"]:
+            self.dump_struct(ln, prototype)
+            return
+
+        self.output_declaration(self.entry.decl_type, prototype,
+                                entry=self.entry)
+
+    def dump_function(self, ln, prototype):
+        """
+        Stores a function of function macro inside self.entries array.
+        """
+
+        func_macro = False
+        return_type = ''
+        decl_type = 'function'
+
+        # Prefixes that would be removed
+        sub_prefixes = [
+            (r"^static +", "", 0),
+            (r"^extern +", "", 0),
+            (r"^asmlinkage +", "", 0),
+            (r"^inline +", "", 0),
+            (r"^__inline__ +", "", 0),
+            (r"^__inline +", "", 0),
+            (r"^__always_inline +", "", 0),
+            (r"^noinline +", "", 0),
+            (r"^__FORTIFY_INLINE +", "", 0),
+            (r"__init +", "", 0),
+            (r"__init_or_module +", "", 0),
+            (r"__deprecated +", "", 0),
+            (r"__flatten +", "", 0),
+            (r"__meminit +", "", 0),
+            (r"__must_check +", "", 0),
+            (r"__weak +", "", 0),
+            (r"__sched +", "", 0),
+            (r"_noprof", "", 0),
+            (r"__printf\s*\(\s*\d*\s*,\s*\d*\s*\) +", "", 0),
+            (r"__(?:re)?alloc_size\s*\(\s*\d+\s*(?:,\s*\d+\s*)?\) +", "", 0),
+            (r"__diagnose_as\s*\(\s*\S+\s*(?:,\s*\d+\s*)*\) +", "", 0),
+            (r"DECL_BUCKET_PARAMS\s*\(\s*(\S+)\s*,\s*(\S+)\s*\)", r"\1, \2", 0),
+            (r"__attribute_const__ +", "", 0),
+
+            # It seems that Python support for re.X is broken:
+            # At least for me (Python 3.13), this didn't work
+#            (r"""
+#              __attribute__\s*\(\(
+#                (?:
+#                    [\w\s]+          # attribute name
+#                    (?:\([^)]*\))?   # attribute arguments
+#                    \s*,?            # optional comma at the end
+#                )+
+#              \)\)\s+
+#             """, "", re.X),
+
+            # So, remove whitespaces and comments from it
+            (r"__attribute__\s*\(\((?:[\w\s]+(?:\([^)]*\))?\s*,?)+\)\)\s+", "", 0),
+        ]
+
+        for search, sub, flags in sub_prefixes:
+            prototype = KernRe(search, flags).sub(sub, prototype)
+
+        # Macros are a special case, as they change the prototype format
+        new_proto = KernRe(r"^#\s*define\s+").sub("", prototype)
+        if new_proto != prototype:
+            is_define_proto = True
+            prototype = new_proto
+        else:
+            is_define_proto = False
+
+        # Yes, this truly is vile.  We are looking for:
+        # 1. Return type (may be nothing if we're looking at a macro)
+        # 2. Function name
+        # 3. Function parameters.
+        #
+        # All the while we have to watch out for function pointer parameters
+        # (which IIRC is what the two sections are for), C types (these
+        # regexps don't even start to express all the possibilities), and
+        # so on.
+        #
+        # If you mess with these regexps, it's a good idea to check that
+        # the following functions' documentation still comes out right:
+        # - parport_register_device (function pointer parameters)
+        # - atomic_set (macro)
+        # - pci_match_device, __copy_to_user (long return type)
+
+        name = r'[a-zA-Z0-9_~:]+'
+        prototype_end1 = r'[^\(]*'
+        prototype_end2 = r'[^\{]*'
+        prototype_end = fr'\(({prototype_end1}|{prototype_end2})\)'
+
+        # Besides compiling, Perl qr{[\w\s]+} works as a non-capturing group.
+        # So, this needs to be mapped in Python with (?:...)? or (?:...)+
+
+        type1 = r'(?:[\w\s]+)?'
+        type2 = r'(?:[\w\s]+\*+)+'
+
+        found = False
+
+        if is_define_proto:
+            r = KernRe(r'^()(' + name + r')\s+')
+
+            if r.search(prototype):
+                return_type = ''
+                declaration_name = r.group(2)
+                func_macro = True
+
+                found = True
+
+        if not found:
+            patterns = [
+                rf'^()({name})\s*{prototype_end}',
+                rf'^({type1})\s+({name})\s*{prototype_end}',
+                rf'^({type2})\s*({name})\s*{prototype_end}',
+            ]
+
+            for p in patterns:
+                r = KernRe(p)
+
+                if r.match(prototype):
+
+                    return_type = r.group(1)
+                    declaration_name = r.group(2)
+                    args = r.group(3)
+
+                    self.create_parameter_list(ln, decl_type, args, ',',
+                                               declaration_name)
+
+                    found = True
+                    break
+        if not found:
+            self.emit_msg(ln,
+                          f"cannot understand function prototype: '{prototype}'")
+            return
+
+        if self.entry.identifier != declaration_name:
+            self.emit_msg(ln,
+                          f"expecting prototype for {self.entry.identifier}(). Prototype was for {declaration_name}() instead")
+            return
+
+        prms = " ".join(self.entry.parameterlist)
+        self.check_sections(ln, declaration_name, "function",
+                            self.entry.sectcheck, prms)
+
+        self.check_return_section(ln, declaration_name, return_type)
+
+        if 'typedef' in return_type:
+            self.output_declaration(decl_type, declaration_name,
+                                    function=declaration_name,
+                                    typedef=True,
+                                    functiontype=return_type,
+                                    parameterlist=self.entry.parameterlist,
+                                    parameterdescs=self.entry.parameterdescs,
+                                    parametertypes=self.entry.parametertypes,
+                                    parameterdesc_start_lines=self.entry.parameterdesc_start_lines,
+                                    sectionlist=self.entry.sectionlist,
+                                    sections=self.entry.sections,
+                                    section_start_lines=self.entry.section_start_lines,
+                                    purpose=self.entry.declaration_purpose,
+                                    func_macro=func_macro)
+        else:
+            self.output_declaration(decl_type, declaration_name,
+                                    function=declaration_name,
+                                    typedef=False,
+                                    functiontype=return_type,
+                                    parameterlist=self.entry.parameterlist,
+                                    parameterdescs=self.entry.parameterdescs,
+                                    parametertypes=self.entry.parametertypes,
+                                    parameterdesc_start_lines=self.entry.parameterdesc_start_lines,
+                                    sectionlist=self.entry.sectionlist,
+                                    sections=self.entry.sections,
+                                    section_start_lines=self.entry.section_start_lines,
+                                    purpose=self.entry.declaration_purpose,
+                                    func_macro=func_macro)
+
+    def dump_typedef(self, ln, proto):
+        """
+        Stores a typedef inside self.entries array.
+        """
+
+        typedef_type = r'((?:\s+[\w\*]+\b){0,7}\s+(?:\w+\b|\*+))\s*'
+        typedef_ident = r'\*?\s*(\w\S+)\s*'
+        typedef_args = r'\s*\((.*)\);'
+
+        typedef1 = KernRe(r'typedef' + typedef_type + r'\(' + typedef_ident + r'\)' + typedef_args)
+        typedef2 = KernRe(r'typedef' + typedef_type + typedef_ident + typedef_args)
+
+        # Strip comments
+        proto = KernRe(r'/\*.*?\*/', flags=re.S).sub('', proto)
+
+        # Parse function typedef prototypes
+        for r in [typedef1, typedef2]:
+            if not r.match(proto):
+                continue
+
+            return_type = r.group(1).strip()
+            declaration_name = r.group(2)
+            args = r.group(3)
+
+            if self.entry.identifier != declaration_name:
+                self.emit_msg(ln,
+                              f"expecting prototype for typedef {self.entry.identifier}. Prototype was for typedef {declaration_name} instead\n")
+                return
+
+            decl_type = 'function'
+            self.create_parameter_list(ln, decl_type, args, ',', declaration_name)
+
+            self.output_declaration(decl_type, declaration_name,
+                                    function=declaration_name,
+                                    typedef=True,
+                                    functiontype=return_type,
+                                    parameterlist=self.entry.parameterlist,
+                                    parameterdescs=self.entry.parameterdescs,
+                                    parametertypes=self.entry.parametertypes,
+                                    parameterdesc_start_lines=self.entry.parameterdesc_start_lines,
+                                    sectionlist=self.entry.sectionlist,
+                                    sections=self.entry.sections,
+                                    section_start_lines=self.entry.section_start_lines,
+                                    purpose=self.entry.declaration_purpose)
+            return
+
+        # Handle nested parentheses or brackets
+        r = KernRe(r'(\(*.\)\s*|\[*.\]\s*);$')
+        while r.search(proto):
+            proto = r.sub('', proto)
+
+        # Parse simple typedefs
+        r = KernRe(r'typedef.*\s+(\w+)\s*;')
+        if r.match(proto):
+            declaration_name = r.group(1)
+
+            if self.entry.identifier != declaration_name:
+                self.emit_msg(ln,
+                              f"expecting prototype for typedef {self.entry.identifier}. Prototype was for typedef {declaration_name} instead\n")
+                return
+
+            self.output_declaration('typedef', declaration_name,
+                                    typedef=declaration_name,
+                                    sectionlist=self.entry.sectionlist,
+                                    sections=self.entry.sections,
+                                    section_start_lines=self.entry.section_start_lines,
+                                    purpose=self.entry.declaration_purpose)
+            return
+
+        self.emit_msg(ln, "error: Cannot parse typedef!")
+
+    @staticmethod
+    def process_export(function_set, line):
+        """
+        process EXPORT_SYMBOL* tags
+
+        This method doesn't use any variable from the class, so declare it
+        with a staticmethod decorator.
+        """
+
+        # Note: it accepts only one EXPORT_SYMBOL* per line, as having
+        # multiple export lines would violate Kernel coding style.
+
+        if export_symbol.search(line):
+            symbol = export_symbol.group(2)
+            function_set.add(symbol)
+            return
+
+        if export_symbol_ns.search(line):
+            symbol = export_symbol_ns.group(2)
+            function_set.add(symbol)
+
+    def process_normal(self, ln, line):
+        """
+        STATE_NORMAL: looking for the /** to begin everything.
+        """
+
+        if not doc_start.match(line):
+            return
+
+        # start a new entry
+        self.reset_state(ln)
+        self.entry.in_doc_sect = False
+
+        # next line is always the function name
+        self.state = state.NAME
+
+    def process_name(self, ln, line):
+        """
+        STATE_NAME: Looking for the "name - description" line
+        """
+
+        if doc_block.search(line):
+            self.entry.new_start_line = ln
+
+            if not doc_block.group(1):
+                self.entry.section = self.section_intro
+            else:
+                self.entry.section = doc_block.group(1)
+
+            self.entry.identifier = self.entry.section
+            self.state = state.DOCBLOCK
+            return
+
+        if doc_decl.search(line):
+            self.entry.identifier = doc_decl.group(1)
+            self.entry.is_kernel_comment = False
+
+            decl_start = str(doc_com)       # comment block asterisk
+            fn_type = r"(?:\w+\s*\*\s*)?"  # type (for non-functions)
+            parenthesis = r"(?:\(\w*\))?"   # optional parenthesis on function
+            decl_end = r"(?:[-:].*)"         # end of the name part
+
+            # test for pointer declaration type, foo * bar() - desc
+            r = KernRe(fr"^{decl_start}([\w\s]+?){parenthesis}?\s*{decl_end}?$")
+            if r.search(line):
+                self.entry.identifier = r.group(1)
+
+            # Test for data declaration
+            r = KernRe(r"^\s*\*?\s*(struct|union|enum|typedef)\b\s*(\w*)")
+            if r.search(line):
+                self.entry.decl_type = r.group(1)
+                self.entry.identifier = r.group(2)
+                self.entry.is_kernel_comment = True
+            else:
+                # Look for foo() or static void foo() - description;
+                # or misspelt identifier
+
+                r1 = KernRe(fr"^{decl_start}{fn_type}(\w+)\s*{parenthesis}\s*{decl_end}?$")
+                r2 = KernRe(fr"^{decl_start}{fn_type}(\w+[^-:]*){parenthesis}\s*{decl_end}$")
+
+                for r in [r1, r2]:
+                    if r.search(line):
+                        self.entry.identifier = r.group(1)
+                        self.entry.decl_type = "function"
+
+                        r = KernRe(r"define\s+")
+                        self.entry.identifier = r.sub("", self.entry.identifier)
+                        self.entry.is_kernel_comment = True
+                        break
+
+            self.entry.identifier = self.entry.identifier.strip(" ")
+
+            self.state = state.BODY
+
+            # if there's no @param blocks need to set up default section here
+            self.entry.section = SECTION_DEFAULT
+            self.entry.new_start_line = ln + 1
+
+            r = KernRe("[-:](.*)")
+            if r.search(line):
+                # strip leading/trailing/multiple spaces
+                self.entry.descr = r.group(1).strip(" ")
+
+                r = KernRe(r"\s+")
+                self.entry.descr = r.sub(" ", self.entry.descr)
+                self.entry.declaration_purpose = self.entry.descr
+                self.state = state.BODY_MAYBE
+            else:
+                self.entry.declaration_purpose = ""
+
+            if not self.entry.is_kernel_comment:
+                self.emit_msg(ln,
+                              f"This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst\n{line}")
+                self.state = state.NORMAL
+
+            if not self.entry.declaration_purpose and self.config.wshort_desc:
+                self.emit_msg(ln,
+                              f"missing initial short description on line:\n{line}")
+
+            if not self.entry.identifier and self.entry.decl_type != "enum":
+                self.emit_msg(ln,
+                              f"wrong kernel-doc identifier on line:\n{line}")
+                self.state = state.NORMAL
+
+            if self.config.verbose:
+                self.emit_msg(ln,
+                              f"Scanning doc for {self.entry.decl_type} {self.entry.identifier}",
+                                  warning=False)
+
+            return
+
+        # Failed to find an identifier. Emit a warning
+        self.emit_msg(ln, f"Cannot find identifier on line:\n{line}")
+
+    def process_body(self, ln, line):
+        """
+        STATE_BODY and STATE_BODY_MAYBE: the bulk of a kerneldoc comment.
+        """
+
+        if self.state == state.BODY_WITH_BLANK_LINE:
+            r = KernRe(r"\s*\*\s?\S")
+            if r.match(line):
+                self.dump_section()
+                self.entry.section = SECTION_DEFAULT
+                self.entry.new_start_line = ln
+                self.entry.contents = ""
+
+        if doc_sect.search(line):
+            self.entry.in_doc_sect = True
+            newsection = doc_sect.group(1)
+
+            if newsection.lower() in ["description", "context"]:
+                newsection = newsection.title()
+
+            # Special case: @return is a section, not a param description
+            if newsection.lower() in ["@return", "@returns",
+                                      "return", "returns"]:
+                newsection = "Return"
+
+            # Perl kernel-doc has a check here for contents before sections.
+            # the logic there is always false, as in_doc_sect variable is
+            # always true. So, just don't implement Wcontents_before_sections
+
+            # .title()
+            newcontents = doc_sect.group(2)
+            if not newcontents:
+                newcontents = ""
+
+            if self.entry.contents.strip("\n"):
+                self.dump_section()
+
+            self.entry.new_start_line = ln
+            self.entry.section = newsection
+            self.entry.leading_space = None
+
+            self.entry.contents = newcontents.lstrip()
+            if self.entry.contents:
+                self.entry.contents += "\n"
+
+            self.state = state.BODY
+            return
+
+        if doc_end.search(line):
+            self.dump_section()
+
+            # Look for doc_com + <text> + doc_end:
+            r = KernRe(r'\s*\*\s*[a-zA-Z_0-9:\.]+\*/')
+            if r.match(line):
+                self.emit_msg(ln, f"suspicious ending line: {line}")
+
+            self.entry.prototype = ""
+            self.entry.new_start_line = ln + 1
+
+            self.state = state.PROTO
+            return
+
+        if doc_content.search(line):
+            cont = doc_content.group(1)
+
+            if cont == "":
+                if self.entry.section == self.section_context:
+                    self.dump_section()
+
+                    self.entry.new_start_line = ln
+                    self.state = state.BODY
+                else:
+                    if self.entry.section != SECTION_DEFAULT:
+                        self.state = state.BODY_WITH_BLANK_LINE
+                    else:
+                        self.state = state.BODY
+
+                    self.entry.contents += "\n"
+
+            elif self.state == state.BODY_MAYBE:
+
+                # Continued declaration purpose
+                self.entry.declaration_purpose = self.entry.declaration_purpose.rstrip()
+                self.entry.declaration_purpose += " " + cont
+
+                r = KernRe(r"\s+")
+                self.entry.declaration_purpose = r.sub(' ',
+                                                       self.entry.declaration_purpose)
+
+            else:
+                if self.entry.section.startswith('@') or        \
+                   self.entry.section == self.section_context:
+                    if self.entry.leading_space is None:
+                        r = KernRe(r'^(\s+)')
+                        if r.match(cont):
+                            self.entry.leading_space = len(r.group(1))
+                        else:
+                            self.entry.leading_space = 0
+
+                    # Double-check if leading space are realy spaces
+                    pos = 0
+                    for i in range(0, self.entry.leading_space):
+                        if cont[i] != " ":
+                            break
+                        pos += 1
+
+                    cont = cont[pos:]
+
+                    # NEW LOGIC:
+                    # In case it is different, update it
+                    if self.entry.leading_space != pos:
+                        self.entry.leading_space = pos
+
+                self.entry.contents += cont + "\n"
+            return
+
+        # Unknown line, ignore
+        self.emit_msg(ln, f"bad line: {line}")
+
+    def process_inline(self, ln, line):
+        """STATE_INLINE: docbook comments within a prototype."""
+
+        if self.inline_doc_state == state.INLINE_NAME and \
+           doc_inline_sect.search(line):
+            self.entry.section = doc_inline_sect.group(1)
+            self.entry.new_start_line = ln
+
+            self.entry.contents = doc_inline_sect.group(2).lstrip()
+            if self.entry.contents != "":
+                self.entry.contents += "\n"
+
+            self.inline_doc_state = state.INLINE_TEXT
+            # Documentation block end */
+            return
+
+        if doc_inline_end.search(line):
+            if self.entry.contents not in ["", "\n"]:
+                self.dump_section()
+
+            self.state = state.PROTO
+            self.inline_doc_state = state.INLINE_NA
+            return
+
+        if doc_content.search(line):
+            if self.inline_doc_state == state.INLINE_TEXT:
+                self.entry.contents += doc_content.group(1) + "\n"
+                if not self.entry.contents.strip(" ").rstrip("\n"):
+                    self.entry.contents = ""
+
+            elif self.inline_doc_state == state.INLINE_NAME:
+                self.emit_msg(ln,
+                              f"Incorrect use of kernel-doc format: {line}")
+
+                self.inline_doc_state = state.INLINE_ERROR
+
+    def syscall_munge(self, ln, proto):         # pylint: disable=W0613
+        """
+        Handle syscall definitions
+        """
+
+        is_void = False
+
+        # Strip newlines/CR's
+        proto = re.sub(r'[\r\n]+', ' ', proto)
+
+        # Check if it's a SYSCALL_DEFINE0
+        if 'SYSCALL_DEFINE0' in proto:
+            is_void = True
+
+        # Replace SYSCALL_DEFINE with correct return type & function name
+        proto = KernRe(r'SYSCALL_DEFINE.*\(').sub('long sys_', proto)
+
+        r = KernRe(r'long\s+(sys_.*?),')
+        if r.search(proto):
+            proto = KernRe(',').sub('(', proto, count=1)
+        elif is_void:
+            proto = KernRe(r'\)').sub('(void)', proto, count=1)
+
+        # Now delete all of the odd-numbered commas in the proto
+        # so that argument types & names don't have a comma between them
+        count = 0
+        length = len(proto)
+
+        if is_void:
+            length = 0  # skip the loop if is_void
+
+        for ix in range(length):
+            if proto[ix] == ',':
+                count += 1
+                if count % 2 == 1:
+                    proto = proto[:ix] + ' ' + proto[ix + 1:]
+
+        return proto
+
+    def tracepoint_munge(self, ln, proto):
+        """
+        Handle tracepoint definitions
+        """
+
+        tracepointname = None
+        tracepointargs = None
+
+        # Match tracepoint name based on different patterns
+        r = KernRe(r'TRACE_EVENT\((.*?),')
+        if r.search(proto):
+            tracepointname = r.group(1)
+
+        r = KernRe(r'DEFINE_SINGLE_EVENT\((.*?),')
+        if r.search(proto):
+            tracepointname = r.group(1)
+
+        r = KernRe(r'DEFINE_EVENT\((.*?),(.*?),')
+        if r.search(proto):
+            tracepointname = r.group(2)
+
+        if tracepointname:
+            tracepointname = tracepointname.lstrip()
+
+        r = KernRe(r'TP_PROTO\((.*?)\)')
+        if r.search(proto):
+            tracepointargs = r.group(1)
+
+        if not tracepointname or not tracepointargs:
+            self.emit_msg(ln,
+                          f"Unrecognized tracepoint format:\n{proto}\n")
+        else:
+            proto = f"static inline void trace_{tracepointname}({tracepointargs})"
+            self.entry.identifier = f"trace_{self.entry.identifier}"
+
+        return proto
+
+    def process_proto_function(self, ln, line):
+        """Ancillary routine to process a function prototype"""
+
+        # strip C99-style comments to end of line
+        r = KernRe(r"\/\/.*$", re.S)
+        line = r.sub('', line)
+
+        if KernRe(r'\s*#\s*define').match(line):
+            self.entry.prototype = line
+        elif line.startswith('#'):
+            # Strip other macros like #ifdef/#ifndef/#endif/...
+            pass
+        else:
+            r = KernRe(r'([^\{]*)')
+            if r.match(line):
+                self.entry.prototype += r.group(1) + " "
+
+        if '{' in line or ';' in line or KernRe(r'\s*#\s*define').match(line):
+            # strip comments
+            r = KernRe(r'/\*.*?\*/')
+            self.entry.prototype = r.sub('', self.entry.prototype)
+
+            # strip newlines/cr's
+            r = KernRe(r'[\r\n]+')
+            self.entry.prototype = r.sub(' ', self.entry.prototype)
+
+            # strip leading spaces
+            r = KernRe(r'^\s+')
+            self.entry.prototype = r.sub('', self.entry.prototype)
+
+            # Handle self.entry.prototypes for function pointers like:
+            #       int (*pcs_config)(struct foo)
+
+            r = KernRe(r'^(\S+\s+)\(\s*\*(\S+)\)')
+            self.entry.prototype = r.sub(r'\1\2', self.entry.prototype)
+
+            if 'SYSCALL_DEFINE' in self.entry.prototype:
+                self.entry.prototype = self.syscall_munge(ln,
+                                                          self.entry.prototype)
+
+            r = KernRe(r'TRACE_EVENT|DEFINE_EVENT|DEFINE_SINGLE_EVENT')
+            if r.search(self.entry.prototype):
+                self.entry.prototype = self.tracepoint_munge(ln,
+                                                             self.entry.prototype)
+
+            self.dump_function(ln, self.entry.prototype)
+            self.reset_state(ln)
+
+    def process_proto_type(self, ln, line):
+        """Ancillary routine to process a type"""
+
+        # Strip newlines/cr's.
+        line = KernRe(r'[\r\n]+', re.S).sub(' ', line)
+
+        # Strip leading spaces
+        line = KernRe(r'^\s+', re.S).sub('', line)
+
+        # Strip trailing spaces
+        line = KernRe(r'\s+$', re.S).sub('', line)
+
+        # Strip C99-style comments to the end of the line
+        line = KernRe(r"\/\/.*$", re.S).sub('', line)
+
+        # To distinguish preprocessor directive from regular declaration later.
+        if line.startswith('#'):
+            line += ";"
+
+        r = KernRe(r'([^\{\};]*)([\{\};])(.*)')
+        while True:
+            if r.search(line):
+                if self.entry.prototype:
+                    self.entry.prototype += " "
+                self.entry.prototype += r.group(1) + r.group(2)
+
+                self.entry.brcount += r.group(2).count('{')
+                self.entry.brcount -= r.group(2).count('}')
+
+                self.entry.brcount = max(self.entry.brcount, 0)
+
+                if r.group(2) == ';' and self.entry.brcount == 0:
+                    self.dump_declaration(ln, self.entry.prototype)
+                    self.reset_state(ln)
+                    break
+
+                line = r.group(3)
+            else:
+                self.entry.prototype += line
+                break
+
+    def process_proto(self, ln, line):
+        """STATE_PROTO: reading a function/whatever prototype."""
+
+        if doc_inline_oneline.search(line):
+            self.entry.section = doc_inline_oneline.group(1)
+            self.entry.contents = doc_inline_oneline.group(2)
+
+            if self.entry.contents != "":
+                self.entry.contents += "\n"
+                self.dump_section(start_new=False)
+
+        elif doc_inline_start.search(line):
+            self.state = state.INLINE
+            self.inline_doc_state = state.INLINE_NAME
+
+        elif self.entry.decl_type == 'function':
+            self.process_proto_function(ln, line)
+
+        else:
+            self.process_proto_type(ln, line)
+
+    def process_docblock(self, ln, line):
+        """STATE_DOCBLOCK: within a DOC: block."""
+
+        if doc_end.search(line):
+            self.dump_section()
+            self.output_declaration("doc", self.entry.identifier,
+                                    sectionlist=self.entry.sectionlist,
+                                    sections=self.entry.sections,
+                                    section_start_lines=self.entry.section_start_lines)
+            self.reset_state(ln)
+
+        elif doc_content.search(line):
+            self.entry.contents += doc_content.group(1) + "\n"
+
+    def parse_export(self):
+        """
+        Parses EXPORT_SYMBOL* macros from a single Kernel source file.
+        """
+
+        export_table = set()
+
+        try:
+            with open(self.fname, "r", encoding="utf8",
+                      errors="backslashreplace") as fp:
+
+                for line in fp:
+                    self.process_export(export_table, line)
+
+        except IOError:
+            return None
+
+        return export_table
+
+    def parse_kdoc(self):
+        """
+        Open and process each line of a C source file.
+        The parsing is controlled via a state machine, and the line is passed
+        to a different process function depending on the state. The process
+        function may update the state as needed.
+
+        Besides parsing kernel-doc tags, it also parses export symbols.
+        """
+
+        cont = False
+        prev = ""
+        prev_ln = None
+        export_table = set()
+
+        try:
+            with open(self.fname, "r", encoding="utf8",
+                      errors="backslashreplace") as fp:
+                for ln, line in enumerate(fp):
+
+                    line = line.expandtabs().strip("\n")
+
+                    # Group continuation lines on prototypes
+                    if self.state == state.PROTO:
+                        if line.endswith("\\"):
+                            prev += line.rstrip("\\")
+                            cont = True
+
+                            if not prev_ln:
+                                prev_ln = ln
+
+                            continue
+
+                        if cont:
+                            ln = prev_ln
+                            line = prev + line
+                            prev = ""
+                            cont = False
+                            prev_ln = None
+
+                    self.config.log.debug("%d %s%s: %s",
+                                          ln, state.name[self.state],
+                                          state.inline_name[self.inline_doc_state],
+                                          line)
+
+                    # This is an optimization over the original script.
+                    # There, when export_file was used for the same file,
+                    # it was read twice. Here, we use the already-existing
+                    # loop to parse exported symbols as well.
+                    #
+                    # TODO: It should be noticed that not all states are
+                    # needed here. On a future cleanup, process export only
+                    # at the states that aren't handling comment markups.
+                    self.process_export(export_table, line)
+
+                    # Hand this line to the appropriate state handler
+                    if self.state == state.NORMAL:
+                        self.process_normal(ln, line)
+                    elif self.state == state.NAME:
+                        self.process_name(ln, line)
+                    elif self.state in [state.BODY, state.BODY_MAYBE,
+                                        state.BODY_WITH_BLANK_LINE]:
+                        self.process_body(ln, line)
+                    elif self.state == state.INLINE:  # scanning for inline parameters
+                        self.process_inline(ln, line)
+                    elif self.state == state.PROTO:
+                        self.process_proto(ln, line)
+                    elif self.state == state.DOCBLOCK:
+                        self.process_docblock(ln, line)
+        except OSError:
+            self.config.log.error(f"Error: Cannot open file {self.fname}")
+
+        return export_table, self.entries