SF: Parse Physical display size in framework

More EDID fields are required as a part of migrating to EDID-based
display IDs. This CL parses the physical display size in CM from bytes
21-22 of block 0 in the EDID blob and serves it as a part of the Edid
struct.

Later, amongst others, this value will be used to fabricate a unique
display ID that is based on the display's EDID.

See:
1. EDID spec: https://glenwing.github.io/docs/VESA-EEDID-A2.pdf
2. https://en.wikipedia.org/wiki/Extended_Display_Identification_Data#Structure,_version_1.4

Flag: com.android.graphics.surfaceflinger.flags.stable_edid_ids
Bug: 378922658
Test: DisplayIdentification_test
Change-Id: I0bb27f267421941aa56f6147082a05ea3b13f33f

3 files changed, 24 insertions, 1 deletions

diff --git a/libs/ui/DisplayIdentification.cpp b/libs/ui/DisplayIdentification.cpp
index 8b13d78840..503f92ff32 100644
--- a/libs/ui/DisplayIdentification.cpp
+++ b/libs/ui/DisplayIdentification.cpp
@@ -212,6 +212,15 @@ std::optional<Edid> parseEdid(const DisplayIdentificationData& edid) {
     ALOGW_IF(manufactureOrModelYear <= 0xf,
              "Invalid EDID: model year or manufacture year cannot be in the range [0x0, 0xf].");
 
+    constexpr size_t kMaxHorizontalPhysicalSizeOffset = 21;
+    constexpr size_t kMaxVerticalPhysicalSizeOffset = 22;
+    if (edid.size() < kMaxVerticalPhysicalSizeOffset + sizeof(uint8_t)) {
+        ALOGE("Invalid EDID: display's physical size is truncated.");
+        return {};
+    }
+    ui::Size maxPhysicalSizeInCm(edid[kMaxHorizontalPhysicalSizeOffset],
+                                 edid[kMaxVerticalPhysicalSizeOffset]);
+
     constexpr size_t kDescriptorOffset = 54;
     if (edid.size() < kDescriptorOffset) {
         ALOGE("Invalid EDID: descriptors are missing.");
@@ -346,6 +355,7 @@ std::optional<Edid> parseEdid(const DisplayIdentificationData& edid) {
             .displayName = displayName,
             .manufactureOrModelYear = manufactureOrModelYear,
             .manufactureWeek = manufactureWeek,
+            .physicalSizeInCm = maxPhysicalSizeInCm,
             .cea861Block = cea861Block,
             .preferredDetailedTimingDescriptor = preferredDetailedTimingDescriptor,
     };
diff --git a/libs/ui/include/ui/DisplayIdentification.h b/libs/ui/include/ui/DisplayIdentification.h
index 648e024d86..3f938d6c96 100644
--- a/libs/ui/include/ui/DisplayIdentification.h
+++ b/libs/ui/include/ui/DisplayIdentification.h
@@ -74,6 +74,7 @@ struct Edid {
     std::string_view displayName;
     uint8_t manufactureOrModelYear;
     uint8_t manufactureWeek;
+    ui::Size physicalSizeInCm;
     std::optional<Cea861ExtensionBlock> cea861Block;
     std::optional<DetailedTimingDescriptor> preferredDetailedTimingDescriptor;
 };
diff --git a/libs/ui/tests/DisplayIdentification_test.cpp b/libs/ui/tests/DisplayIdentification_test.cpp
index 76e3f66e1b..cf0e98b0c6 100644
--- a/libs/ui/tests/DisplayIdentification_test.cpp
+++ b/libs/ui/tests/DisplayIdentification_test.cpp
@@ -193,6 +193,8 @@ TEST(DisplayIdentificationTest, parseEdid) {
     EXPECT_EQ(12610, edid->productId);
     EXPECT_EQ(21, edid->manufactureOrModelYear);
     EXPECT_EQ(0, edid->manufactureWeek);
+    EXPECT_EQ(26, edid->physicalSizeInCm.width);
+    EXPECT_EQ(16, edid->physicalSizeInCm.height);
     EXPECT_FALSE(edid->cea861Block);
     EXPECT_EQ(1280, edid->preferredDetailedTimingDescriptor->pixelSizeCount.width);
     EXPECT_EQ(800, edid->preferredDetailedTimingDescriptor->pixelSizeCount.height);
@@ -209,6 +211,8 @@ TEST(DisplayIdentificationTest, parseEdid) {
     EXPECT_EQ(10348, edid->productId);
     EXPECT_EQ(22, edid->manufactureOrModelYear);
     EXPECT_EQ(2, edid->manufactureWeek);
+    EXPECT_EQ(64, edid->physicalSizeInCm.width);
+    EXPECT_EQ(40, edid->physicalSizeInCm.height);
     EXPECT_FALSE(edid->cea861Block);
     EXPECT_EQ(1280, edid->preferredDetailedTimingDescriptor->pixelSizeCount.width);
     EXPECT_EQ(800, edid->preferredDetailedTimingDescriptor->pixelSizeCount.height);
@@ -225,6 +229,8 @@ TEST(DisplayIdentificationTest, parseEdid) {
     EXPECT_EQ(2302, edid->productId);
     EXPECT_EQ(21, edid->manufactureOrModelYear);
     EXPECT_EQ(41, edid->manufactureWeek);
+    EXPECT_EQ(16, edid->physicalSizeInCm.width);
+    EXPECT_EQ(9, edid->physicalSizeInCm.height);
     ASSERT_TRUE(edid->cea861Block);
     ASSERT_TRUE(edid->cea861Block->hdmiVendorDataBlock);
     auto physicalAddress = edid->cea861Block->hdmiVendorDataBlock->physicalAddress;
@@ -247,6 +253,8 @@ TEST(DisplayIdentificationTest, parseEdid) {
     EXPECT_EQ(41622, edid->productId);
     EXPECT_EQ(29, edid->manufactureOrModelYear);
     EXPECT_EQ(0, edid->manufactureWeek);
+    EXPECT_EQ(128, edid->physicalSizeInCm.width);
+    EXPECT_EQ(72, edid->physicalSizeInCm.height);
     ASSERT_TRUE(edid->cea861Block);
     ASSERT_TRUE(edid->cea861Block->hdmiVendorDataBlock);
     physicalAddress = edid->cea861Block->hdmiVendorDataBlock->physicalAddress;
@@ -269,6 +277,8 @@ TEST(DisplayIdentificationTest, parseEdid) {
     EXPECT_EQ(0, edid->productId);
     EXPECT_EQ(29, edid->manufactureOrModelYear);
     EXPECT_EQ(18, edid->manufactureWeek);
+    EXPECT_EQ(0, edid->physicalSizeInCm.width);
+    EXPECT_EQ(0, edid->physicalSizeInCm.height);
     ASSERT_TRUE(edid->cea861Block);
     ASSERT_TRUE(edid->cea861Block->hdmiVendorDataBlock);
     physicalAddress = edid->cea861Block->hdmiVendorDataBlock->physicalAddress;
@@ -291,6 +301,8 @@ TEST(DisplayIdentificationTest, parseEdid) {
     EXPECT_EQ(9373, edid->productId);
     EXPECT_EQ(23, edid->manufactureOrModelYear);
     EXPECT_EQ(0xff, edid->manufactureWeek);
+    EXPECT_EQ(52, edid->physicalSizeInCm.width);
+    EXPECT_EQ(29, edid->physicalSizeInCm.height);
     ASSERT_TRUE(edid->cea861Block);
     EXPECT_FALSE(edid->cea861Block->hdmiVendorDataBlock);
     EXPECT_EQ(1360, edid->preferredDetailedTimingDescriptor->pixelSizeCount.width);
@@ -447,4 +459,4 @@ TEST(DisplayIdentificationTest, getVirtualDisplayId) {
 } // namespace android
 
 // TODO(b/129481165): remove the #pragma below and fix conversion issues
-#pragma clang diagnostic pop // ignored "-Wextra"
\ No newline at end of file
+#pragma clang diagnostic pop // ignored "-Wextra"