[PATCH] checkpatch: add DT compatible string documentation checks

[Antony Pavlov]

This adds a simple check that any compatible strings in DeviceTree dts
files are present in Documentation/devicetree/bindings and
in dts/Bindings/.

Vendor prefixes are also checked for existing in vendor-prefixes.txt.

This code is based on linux v4.0-rc6 checkpatch.pl dt-checking code by
Rob Herring & Florian Vaussard:

    Rob Herring (2):
        checkpatch: add DT compatible string documentation checks
        checkpatch: fix wildcard DT compatible string checking

    Florian Vaussard (3):
        checkpatch: fix spurious vendor compatible warnings
        checkpatch: check compatible strings in .c and .h too
        checkpatch: improve the compatible vendor match

Signed-off-by: Antony Pavlov <antonynpavlov at gmail.com>
Cc: Rob Herring <robh at kernel.org>
Cc: Florian Vaussard <florian.vaussard at epfl.ch>
---
 scripts/checkpatch.pl | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index a40d32c..8d96434 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -1466,6 +1466,41 @@ sub process {
 			#print "is_end<$is_end> length<$length>\n";
 		}
 
+# check for DT compatible documentation
+		if (defined $root &&
+			(($realfile =~ /\.dtsi?$/ && $line =~ /^\+\s*compatible\s*=\s*\"/) ||
+			 ($realfile =~ /\.[ch]$/ && $line =~ /^\+.*\.compatible\s*=\s*\"/))) {
+
+			my @compats = $rawline =~ /\"([a-zA-Z0-9\-\,\.\+_]+)\"/g;
+
+			# linux device tree files
+			my $dt_path = $root . "/dts/Bindings/";
+			my $vp_file = $dt_path . "vendor-prefixes.txt";
+
+			# barebox-specific bindings
+			$dt_path = $dt_path . " " . $root . "/Documentation/devicetree/bindings/";
+
+			foreach my $compat (@compats) {
+				my $compat2 = $compat;
+				$compat2 =~ s/\,[a-zA-Z0-9]*\-/\,<\.\*>\-/;
+				my $compat3 = $compat;
+				$compat3 =~ s/\,([a-z]*)[0-9]*\-/\,$1<\.\*>\-/;
+				`grep -Erq "$compat|$compat2|$compat3" $dt_path`;
+				if ( $? >> 8 ) {
+					WARN(
+					     "DT compatible string \"$compat\" appears un-documented -- check $dt_path\n" . $herecurr);
+				}
+
+				next if $compat !~ /^([a-zA-Z0-9\-]+)\,/;
+				my $vendor = $1;
+				`grep -Eq "^$vendor\\b" $vp_file`;
+				if ( $? >> 8 ) {
+					WARN(
+					     "DT compatible string vendor \"$vendor\" appears un-documented -- check $vp_file\n" . $herecurr);
+				}
+			}
+		}
+
 # check we are in a valid source file if not then ignore this hunk
 		next if ($realfile !~ /\.(h|c|s|S|pl|sh)$/);
 
-- 
2.1.4