monitor-parse-edid:

  add support for Detailed Timing Descriptors in CEA EDID Timing
  Extension

2 files changed, 61 insertions, 10 deletions

diff --git a/NEWS b/NEWS
index 193e5ab..3134111 100644
--- a/NEWS
+++ b/NEWS
@@ -10,6 +10,8 @@
 - monitor-parse-edid:
   o print EDID version and the number of EDID extension blocks
   o accept EDID data with multiple extension blocks
+  o add support for Detailed Timing Descriptors in CEA EDID Timing
+    Extension
 
 Version 2.5 - 18 October 2009, by Anssi Hannula
 
diff --git a/monitor-parse-edid b/monitor-parse-edid
index 68fb32b..b8f3515 100755
--- a/monitor-parse-edid
+++ b/monitor-parse-edid
@@ -153,6 +153,16 @@ my %subfields = (
 	8 => 'vertical_blanking_max',
 	8 => 'module_revision',
     ) ],
+    
+    cea_data_block_collection => [ group_by2(
+	3 => 'type',
+	5 => 'size',
+    ) ],
+
+    cea_video_data_block => [ group_by2(
+	1 => 'native',
+	7 => 'mode',
+    ) ],
 );
 
 sub within_limit {
@@ -190,11 +200,26 @@ sub check_parsed_edid {
     '';
 }
 
+sub build_detailed_timing {
+    my ($pixel_clock, $vv) = @_;
+
+    my $h = get_many_bits($vv, 'detailed_timing');
+    $h->{pixel_clock} = $pixel_clock / 100; # to have it in MHz
+    my %detailed_timing_field_size = map { $_->[1], $_->[0] } @{$subfields{detailed_timing}};
+    foreach my $field (keys %detailed_timing_field_size) {
+	$field =~ s/_hi$// or next;
+	my $hi = delete($h->{$field . '_hi'});
+	$h->{$field} += $hi << $detailed_timing_field_size{$field};
+    }
+    $h;
+}
+
 sub parse_edid {
     my ($raw_edid, $verbose) = @_;
 
     my %edid;
-    my @vals = unpack(join('', map { $_->[0] } @edid_info), $raw_edid);
+    my ($main_edid, @eedid_blocks) = unpack("a128" x (length($raw_edid) / 128), $raw_edid);
+    my @vals = unpack(join('', map { $_->[0] } @edid_info), $main_edid);
     my $i;
     foreach (@edid_info) {
 	my ($field, $v) = ($_->[1], $vals[$i++]);
@@ -237,15 +262,7 @@ sub parse_edid {
 
 		if ($pixel_clock) {
 		    # detailed timing
-		    my $h = get_many_bits($vv, 'detailed_timing');
-		    $h->{pixel_clock} = $pixel_clock / 100; # to have it in MHz
-
-		    my %detailed_timing_field_size = map { $_->[1], $_->[0] } @{$subfields{detailed_timing}};
-		    foreach my $field (keys %detailed_timing_field_size) {
-			$field =~ s/_hi$// or next;
-			my $hi = delete($h->{$field . '_hi'});
-			$h->{$field} += $hi << $detailed_timing_field_size{$field};
-		    }
+		    my $h = build_detailed_timing($pixel_clock, $vv);
 		    push @{$edid{detailed_timings}}, $h
 		      if $h->{horizontal_active} > 0 && $h->{vertical_active} > 0;
 		} else {
@@ -307,6 +324,38 @@ sub parse_edid {
 	$edid{$field} = $v if $field && $field !~ /^_/;
     }
 
+    foreach (@eedid_blocks) {
+	my ($tag, $v) = unpack("C a*", $_);
+
+	if ($tag == 0x02) { # CEA EDID
+	    my $dtd_offset;
+	    ($dtd_offset, $v) = unpack("x C x a*", $v);
+
+	    next if $dtd_offset < 4;
+	    $dtd_offset -= 4;
+
+	    while ($dtd_offset > 0) {
+		my $h = get_many_bits($v, 'cea_data_block_collection');
+		$dtd_offset -= $h->{size} + 1;
+
+		$v = unpack("x x$h->{size} a*", $v);
+		if ($h->{type} == 0x02) { # Video Data Block
+		    $verbose && warn "video data block not handled\n";
+		}
+	    }
+
+	    while (length($v) >= 18) {
+		(my $pixel_clock, my $vv, $v) = unpack("v a16 a*", $v);
+		last if !$pixel_clock;
+		my $h = build_detailed_timing($pixel_clock, $vv);
+		push @{$edid{detailed_timings}}, $h
+		    if $h->{horizontal_active} > 0 && $h->{vertical_active} > 0;
+	    }
+	} else {
+	    $verbose && warn "parse_edid: unknown tag $tag\n";
+	}
+    }
+
     $edid{max_size_precision} = 'cm';
     $edid{EISA_ID} = $edid{manufacturer_name} . sprintf('%04x', $edid{product_code}) if $edid{product_code};