checkpatch: fix spurious vendor compatible warnings

With a compatible string like

  compatible = "foo";

checkpatch will currently try to find "foo" in vendor-prefixes.txt,
which is wrong since the vendor prefix is empty in this specific case.

Skip the vendor test if the compatible is not like

  compatible = "vendor,something";

Signed-off-by: Florian Vaussard <florian.vaussard@epfl.ch>
Cc: Joe Perches <joe@perches.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 3b268b3f2362..75b587e8ddfd 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2088,10 +2088,10 @@ sub process {
                                              "DT compatible string \"$compat\" appears un-documented -- check $dt_path\n" . $herecurr);
                                 }
 
-                                my $vendor = $compat;
                                 my $vendor_path = $dt_path . "vendor-prefixes.txt";
                                 next if (! -f $vendor_path);
-                                $vendor =~ s/^([a-zA-Z0-9\-]+)\,.*/$1/;
+                                next if $compat !~ /^([a-zA-Z0-9\-]+)\,/;
+                                my $vendor = $1;
                                 `grep -Eq "$vendor" $vendor_path`;
                                 if ( $? >> 8 ) {
                                         WARN("UNDOCUMENTED_DT_STRING",