commit 8d0a0c43c1416e8540b0adf527be2ec5c69cccff
author Lucas Berthou <berlu@google.com> Tue Aug 27 14:32:31 2024 +0000
committer Lucas Berthou <berlu@google.com> Thu Sep 12 15:34:14 2024 +0000
tree 682fb7f95b794e517bc233658a1138930bae3728
parent 5b0bdd2cd9b9920679fd530b8b136559d5441343

SF: parsing Detailed Timing Descriptor in the framework

The first DTD in an edid is the preferred timing which allows to get
a more precise and more often correct physical size for a display. This
can be used to estimate or correct the dpi in case the edid reports the
wrong size and hwc is not providing the right value.

See edid spec: https://glenwing.github.io/docs/VESA-EEDID-A2.pdf

Flag: com.android.graphics.surfaceflinger.flags.correct_dpi_with_display_size
Bug: 361413340
Test: DisplayIdentification_test
Test: HWComposerTest
Test: manual - see bug and doc

Change-Id: I0bb85dcf8039f923f1ac892c4a1d6bda771dbf4f

libs/ui/tests/DisplayIdentification_test.cpp

diff --git a/libs/ui/tests/DisplayIdentification_test.cpp b/libs/ui/tests/DisplayIdentification_test.cpp
index 721b466..76e3f66 100644
--- a/libs/ui/tests/DisplayIdentification_test.cpp
+++ b/libs/ui/tests/DisplayIdentification_test.cpp
@@ -194,6 +194,10 @@
     EXPECT_EQ(21, edid->manufactureOrModelYear);
     EXPECT_EQ(0, edid->manufactureWeek);
     EXPECT_FALSE(edid->cea861Block);
+    EXPECT_EQ(1280, edid->preferredDetailedTimingDescriptor->pixelSizeCount.width);
+    EXPECT_EQ(800, edid->preferredDetailedTimingDescriptor->pixelSizeCount.height);
+    EXPECT_EQ(261, edid->preferredDetailedTimingDescriptor->physicalSizeInMm.width);
+    EXPECT_EQ(163, edid->preferredDetailedTimingDescriptor->physicalSizeInMm.height);
 
     edid = parseEdid(getExternalEdid());
     ASSERT_TRUE(edid);
@@ -206,6 +210,10 @@
     EXPECT_EQ(22, edid->manufactureOrModelYear);
     EXPECT_EQ(2, edid->manufactureWeek);
     EXPECT_FALSE(edid->cea861Block);
+    EXPECT_EQ(1280, edid->preferredDetailedTimingDescriptor->pixelSizeCount.width);
+    EXPECT_EQ(800, edid->preferredDetailedTimingDescriptor->pixelSizeCount.height);
+    EXPECT_EQ(641, edid->preferredDetailedTimingDescriptor->physicalSizeInMm.width);
+    EXPECT_EQ(400, edid->preferredDetailedTimingDescriptor->physicalSizeInMm.height);
 
     edid = parseEdid(getExternalEedid());
     ASSERT_TRUE(edid);
@@ -224,6 +232,10 @@
     EXPECT_EQ(0, physicalAddress.b);
     EXPECT_EQ(0, physicalAddress.c);
     EXPECT_EQ(0, physicalAddress.d);
+    EXPECT_EQ(1366, edid->preferredDetailedTimingDescriptor->pixelSizeCount.width);
+    EXPECT_EQ(768, edid->preferredDetailedTimingDescriptor->pixelSizeCount.height);
+    EXPECT_EQ(160, edid->preferredDetailedTimingDescriptor->physicalSizeInMm.width);
+    EXPECT_EQ(90, edid->preferredDetailedTimingDescriptor->physicalSizeInMm.height);
 
     edid = parseEdid(getPanasonicTvEdid());
     ASSERT_TRUE(edid);
@@ -242,6 +254,10 @@
     EXPECT_EQ(0, physicalAddress.b);
     EXPECT_EQ(0, physicalAddress.c);
     EXPECT_EQ(0, physicalAddress.d);
+    EXPECT_EQ(1920, edid->preferredDetailedTimingDescriptor->pixelSizeCount.width);
+    EXPECT_EQ(1080, edid->preferredDetailedTimingDescriptor->pixelSizeCount.height);
+    EXPECT_EQ(698, edid->preferredDetailedTimingDescriptor->physicalSizeInMm.width);
+    EXPECT_EQ(392, edid->preferredDetailedTimingDescriptor->physicalSizeInMm.height);
 
     edid = parseEdid(getHisenseTvEdid());
     ASSERT_TRUE(edid);
@@ -260,6 +276,10 @@
     EXPECT_EQ(2, physicalAddress.b);
     EXPECT_EQ(3, physicalAddress.c);
     EXPECT_EQ(4, physicalAddress.d);
+    EXPECT_EQ(1920, edid->preferredDetailedTimingDescriptor->pixelSizeCount.width);
+    EXPECT_EQ(1080, edid->preferredDetailedTimingDescriptor->pixelSizeCount.height);
+    EXPECT_EQ(575, edid->preferredDetailedTimingDescriptor->physicalSizeInMm.width);
+    EXPECT_EQ(323, edid->preferredDetailedTimingDescriptor->physicalSizeInMm.height);
 
     edid = parseEdid(getCtlDisplayEdid());
     ASSERT_TRUE(edid);
@@ -273,6 +293,10 @@
     EXPECT_EQ(0xff, edid->manufactureWeek);
     ASSERT_TRUE(edid->cea861Block);
     EXPECT_FALSE(edid->cea861Block->hdmiVendorDataBlock);
+    EXPECT_EQ(1360, edid->preferredDetailedTimingDescriptor->pixelSizeCount.width);
+    EXPECT_EQ(768, edid->preferredDetailedTimingDescriptor->pixelSizeCount.height);
+    EXPECT_EQ(521, edid->preferredDetailedTimingDescriptor->physicalSizeInMm.width);
+    EXPECT_EQ(293, edid->preferredDetailedTimingDescriptor->physicalSizeInMm.height);
 }
 
 TEST(DisplayIdentificationTest, parseInvalidEdid) {