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Message-ID: <aa1819fa5faf786573df298e5e2e7d357ba7d4ad.camel@perches.com>
Subject: [PATCH] checkpatch: Warn when missing newline in return
 sysfs_emit() formats
From:   Joe Perches <joe@perches.com>
To:     Andrew Morton <akpm@linux-foundation.org>,
        Andy Whitcroft <apw@canonical.com>
Cc:     Tomas Winkler <tomas.winkler@intel.com>,
        Greg KH <gregkh@linuxfoundation.org>,
        LKML <linux-kernel@vger.kernel.org>
Date:   Tue, 30 Mar 2021 11:48:34 -0700
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return sysfs_emit() uses should include a newline.

Suggest adding a newline when one is missing.
Add one using --fix too.

Signed-off-by: Joe Perches <joe@perches.com>
---
 scripts/checkpatch.pl | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index d67146d0b33c..4dbda85fd7e5 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -7198,6 +7198,17 @@ sub process {
 			     "Using $1 should generally have parentheses around the comparison\n" . $herecurr);
 		}
 
+# return sysfs_emit(foo, fmt, ...) fmt without newline
+		if ($line =~ /\breturn\s+sysfs_emit\s*\(\s*$FuncArg\s*,\s*($String)/ &&
+		    substr($rawline, $-[6], $+[6] - $-[6]) !~ /\\n"$/) {
+			my $offset = $+[6] - 1;
+			if (WARN("SYSFS_EMIT",
+				 "return sysfs_emit(...) formats should include a terminating newline\n" . $herecurr) &&
+			    $fix) {
+				substr($fixed[$fixlinenr], $offset, 0) = '\\n';
+			}
+		}
+
 # nested likely/unlikely calls
 		if ($line =~ /\b(?:(?:un)?likely)\s*\(\s*!?\s*(IS_ERR(?:_OR_NULL|_VALUE)?|WARN)/) {
 			WARN("LIKELY_MISUSE",