[PATCH v2 24/27] docs: scripts: kernel-doc: accept bitwise negation like ~@var

[Mark Rutland <mark.rutland@arm.com>]

In some cases we'd like to indicate the bitwise negation of a parameter,
e.g.

  ~@var

This will be helpful for describing the atomic andnot operations, where
we'd like to write comments of the form:

  Atomically updates @v to (@v & ~@i)

Which kernel-doc currently transforms to:

  Atomically updates **v** to (**v** & ~**i**)

Rather than the preferable form:

  Atomically updates **v** to (**v** & **~i**)

This is similar to what we did for '!@var' in commit:

  ee2aa7590398 ("scripts: kernel-doc: accept negation like !@var")

This patch follows the same pattern that commit used to permit a '!'
prefix on a param ref, allowing a '~' prefix on a param ref, cuasing
kernel-doc to generate the preferred form above.

Suggested-by: Akira Yokosawa <akiyks@gmail.com>
Link: https://lore.kernel.org/lkml/a5405368-d04c-f95c-ad18-95f429120dbe@gmail.com
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Will Deacon <will@kernel.org>
---
 scripts/kernel-doc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/kernel-doc b/scripts/kernel-doc
index 2486689ffc7b4..eb70c1fd4e868 100755
--- a/scripts/kernel-doc
+++ b/scripts/kernel-doc
@@ -64,7 +64,7 @@ my $type_constant = '\b``([^\`]+)``\b';
 my $type_constant2 = '\%([-_\w]+)';
 my $type_func = '(\w+)\(\)';
 my $type_param = '\@(\w*((\.\w+)|(->\w+))*(\.\.\.)?)';
-my $type_param_ref = '([\!]?)\@(\w*((\.\w+)|(->\w+))*(\.\.\.)?)';
+my $type_param_ref = '([\!~]?)\@(\w*((\.\w+)|(->\w+))*(\.\.\.)?)';
 my $type_fp_param = '\@(\w+)\(\)';  # Special RST handling for func ptr params
 my $type_fp_param2 = '\@(\w+->\S+)\(\)';  # Special RST handling for structs with func ptr params
 my $type_env = '(\$\w+)';
-- 
2.30.2