commit f9854d272c816ca2ad2fec085e17c6591721bff9
author Gil Dekel <gildekel@google.com> Thu Nov 14 14:14:25 2024 -0500
committer Gil Dekel <gildekel@google.com> Sat Nov 16 01:30:59 2024 -0500
tree 0e57c8df7626ee83481719b73e025f0a0356ba35
parent c37c90444774da117f8a4eef14b091f0a54086f2

SF: Hash and cache descriptor block serial number

More EDID fields are required as a part of migrating to EDID-based
display IDs. This CL parses the device's serial number from the serial
number descriptor bloc, (depicted by the FF marker), hashes it using a
stable hash, 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: 378923759
Test: DisplayIdentification_test
Change-Id: If9c9358b0d0850337496740d15419fd0ed330a02

libs/ui/tests/DisplayIdentification_test.cpp

diff --git a/libs/ui/tests/DisplayIdentification_test.cpp b/libs/ui/tests/DisplayIdentification_test.cpp
index fbbe719..d1699e7 100644
--- a/libs/ui/tests/DisplayIdentification_test.cpp
+++ b/libs/ui/tests/DisplayIdentification_test.cpp
@@ -193,6 +193,7 @@
     EXPECT_EQ(12610, edid->productId);
     EXPECT_TRUE(edid->hashedBlockZeroSerialNumberOpt.has_value());
     EXPECT_EQ(ftl::stable_hash("12345678"), edid->hashedBlockZeroSerialNumberOpt.value());
+    EXPECT_FALSE(edid->hashedDescriptorBlockSerialNumberOpt.has_value());
     EXPECT_EQ(21, edid->manufactureOrModelYear);
     EXPECT_EQ(0, edid->manufactureWeek);
     EXPECT_EQ(26, edid->physicalSizeInCm.width);
@@ -213,6 +214,8 @@
     EXPECT_EQ(10348, edid->productId);
     EXPECT_TRUE(edid->hashedBlockZeroSerialNumberOpt.has_value());
     EXPECT_EQ(ftl::stable_hash("16843009"), edid->hashedBlockZeroSerialNumberOpt.value());
+    EXPECT_TRUE(edid->hashedDescriptorBlockSerialNumberOpt.has_value());
+    EXPECT_EQ(ftl::stable_hash("CN4202137Q"), edid->hashedDescriptorBlockSerialNumberOpt.value());
     EXPECT_EQ(22, edid->manufactureOrModelYear);
     EXPECT_EQ(2, edid->manufactureWeek);
     EXPECT_EQ(64, edid->physicalSizeInCm.width);
@@ -233,6 +236,7 @@
     EXPECT_EQ(2302, edid->productId);
     EXPECT_TRUE(edid->hashedBlockZeroSerialNumberOpt.has_value());
     EXPECT_EQ(ftl::stable_hash("87654321"), edid->hashedBlockZeroSerialNumberOpt.value());
+    EXPECT_FALSE(edid->hashedDescriptorBlockSerialNumberOpt.has_value());
     EXPECT_EQ(21, edid->manufactureOrModelYear);
     EXPECT_EQ(41, edid->manufactureWeek);
     EXPECT_EQ(16, edid->physicalSizeInCm.width);
@@ -259,6 +263,7 @@
     EXPECT_EQ(41622, edid->productId);
     EXPECT_TRUE(edid->hashedBlockZeroSerialNumberOpt.has_value());
     EXPECT_EQ(ftl::stable_hash("16843009"), edid->hashedBlockZeroSerialNumberOpt.value());
+    EXPECT_FALSE(edid->hashedDescriptorBlockSerialNumberOpt.has_value());
     EXPECT_EQ(29, edid->manufactureOrModelYear);
     EXPECT_EQ(0, edid->manufactureWeek);
     EXPECT_EQ(128, edid->physicalSizeInCm.width);
@@ -284,6 +289,7 @@
     EXPECT_EQ("Hisense", edid->displayName);
     EXPECT_EQ(0, edid->productId);
     EXPECT_FALSE(edid->hashedBlockZeroSerialNumberOpt.has_value());
+    EXPECT_FALSE(edid->hashedDescriptorBlockSerialNumberOpt.has_value());
     EXPECT_EQ(29, edid->manufactureOrModelYear);
     EXPECT_EQ(18, edid->manufactureWeek);
     EXPECT_EQ(0, edid->physicalSizeInCm.width);
@@ -310,6 +316,7 @@
     EXPECT_EQ(9373, edid->productId);
     EXPECT_TRUE(edid->hashedBlockZeroSerialNumberOpt.has_value());
     EXPECT_EQ(ftl::stable_hash("11223344"), edid->hashedBlockZeroSerialNumberOpt.value());
+    EXPECT_FALSE(edid->hashedDescriptorBlockSerialNumberOpt.has_value());
     EXPECT_EQ(23, edid->manufactureOrModelYear);
     EXPECT_EQ(0xff, edid->manufactureWeek);
     EXPECT_EQ(52, edid->physicalSizeInCm.width);