SF: Generate stable display IDs using EDID
The display IDs generated by HWC are opaque handles. In order for SF and
eventually DisplayManagerService to keep track of more than two displays
and recognize previously seen displays, displays should be given stable
and persistent IDs.
If the HWC supports IComposerClient.getDisplayIdentificationData, SF
parses the EDID structure to generate stable display IDs, which will
be used in a follow-up CL to replace HWC_DISPLAY_{PRIMARY,EXTERNAL}.
Bug: 74619554
Test: dumpsys SurfaceFlinger --display-identification
Test: libsurfaceflinger_unittest
Change-Id: I1a710e2efcf1581fabe48ab96a0eb4e7a5163c0c
diff --git a/services/surfaceflinger/tests/unittests/DisplayIdentificationTest.cpp b/services/surfaceflinger/tests/unittests/DisplayIdentificationTest.cpp
new file mode 100644
index 0000000..9113171
--- /dev/null
+++ b/services/surfaceflinger/tests/unittests/DisplayIdentificationTest.cpp
@@ -0,0 +1,144 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include "DisplayHardware/DisplayIdentification.h"
+
+namespace android {
+namespace {
+
+const unsigned char kInternalEdid[] =
+ "\x00\xff\xff\xff\xff\xff\xff\x00\x4c\xa3\x42\x31\x00\x00\x00\x00"
+ "\x00\x15\x01\x03\x80\x1a\x10\x78\x0a\xd3\xe5\x95\x5c\x60\x90\x27"
+ "\x19\x50\x54\x00\x00\x00\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01"
+ "\x01\x01\x01\x01\x01\x01\x9e\x1b\x00\xa0\x50\x20\x12\x30\x10\x30"
+ "\x13\x00\x05\xa3\x10\x00\x00\x19\x00\x00\x00\x0f\x00\x00\x00\x00"
+ "\x00\x00\x00\x00\x00\x23\x87\x02\x64\x00\x00\x00\x00\xfe\x00\x53"
+ "\x41\x4d\x53\x55\x4e\x47\x0a\x20\x20\x20\x20\x20\x00\x00\x00\xfe"
+ "\x00\x31\x32\x31\x41\x54\x31\x31\x2d\x38\x30\x31\x0a\x20\x00\x45";
+
+const unsigned char kExternalEdid[] =
+ "\x00\xff\xff\xff\xff\xff\xff\x00\x22\xf0\x6c\x28\x01\x01\x01\x01"
+ "\x02\x16\x01\x04\xb5\x40\x28\x78\xe2\x8d\x85\xad\x4f\x35\xb1\x25"
+ "\x0e\x50\x54\x00\x00\x00\x01\x01\x01\x01\x01\x01\x01\x01\x01\x01"
+ "\x01\x01\x01\x01\x01\x01\xe2\x68\x00\xa0\xa0\x40\x2e\x60\x30\x20"
+ "\x36\x00\x81\x90\x21\x00\x00\x1a\xbc\x1b\x00\xa0\x50\x20\x17\x30"
+ "\x30\x20\x36\x00\x81\x90\x21\x00\x00\x1a\x00\x00\x00\xfc\x00\x48"
+ "\x50\x20\x5a\x52\x33\x30\x77\x0a\x20\x20\x20\x20\x00\x00\x00\xff"
+ "\x00\x43\x4e\x34\x32\x30\x32\x31\x33\x37\x51\x0a\x20\x20\x00\x71";
+
+// Extended EDID with timing extension.
+const unsigned char kExternalEedid[] =
+ "\x00\xff\xff\xff\xff\xff\xff\x00\x4c\x2d\xfe\x08\x00\x00\x00\x00"
+ "\x29\x15\x01\x03\x80\x10\x09\x78\x0a\xee\x91\xa3\x54\x4c\x99\x26"
+ "\x0f\x50\x54\xbd\xef\x80\x71\x4f\x81\xc0\x81\x00\x81\x80\x95\x00"
+ "\xa9\xc0\xb3\x00\x01\x01\x02\x3a\x80\x18\x71\x38\x2d\x40\x58\x2c"
+ "\x45\x00\xa0\x5a\x00\x00\x00\x1e\x66\x21\x56\xaa\x51\x00\x1e\x30"
+ "\x46\x8f\x33\x00\xa0\x5a\x00\x00\x00\x1e\x00\x00\x00\xfd\x00\x18"
+ "\x4b\x0f\x51\x17\x00\x0a\x20\x20\x20\x20\x20\x20\x00\x00\x00\xfc"
+ "\x00\x53\x41\x4d\x53\x55\x4e\x47\x0a\x20\x20\x20\x20\x20\x01\x1d"
+ "\x02\x03\x1f\xf1\x47\x90\x04\x05\x03\x20\x22\x07\x23\x09\x07\x07"
+ "\x83\x01\x00\x00\xe2\x00\x0f\x67\x03\x0c\x00\x20\x00\xb8\x2d\x01"
+ "\x1d\x80\x18\x71\x1c\x16\x20\x58\x2c\x25\x00\xa0\x5a\x00\x00\x00"
+ "\x9e\x01\x1d\x00\x72\x51\xd0\x1e\x20\x6e\x28\x55\x00\xa0\x5a\x00"
+ "\x00\x00\x1e\x8c\x0a\xd0\x8a\x20\xe0\x2d\x10\x10\x3e\x96\x00\xa0"
+ "\x5a\x00\x00\x00\x18\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+ "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+ "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xc6";
+
+template <size_t N>
+DisplayIdentificationData asDisplayIdentificationData(const unsigned char (&bytes)[N]) {
+ return DisplayIdentificationData(bytes, bytes + N - 1);
+}
+
+} // namespace
+
+TEST(DisplayIdentificationTest, isEdid) {
+ EXPECT_FALSE(isEdid({}));
+
+ EXPECT_TRUE(isEdid(asDisplayIdentificationData(kInternalEdid)));
+ EXPECT_TRUE(isEdid(asDisplayIdentificationData(kExternalEdid)));
+ EXPECT_TRUE(isEdid(asDisplayIdentificationData(kExternalEedid)));
+}
+
+TEST(DisplayIdentificationTest, parseEdid) {
+ auto edid = parseEdid(asDisplayIdentificationData(kInternalEdid));
+ ASSERT_TRUE(edid);
+ EXPECT_EQ(0x4ca3u, edid->manufacturerId);
+ EXPECT_STREQ("SEC", edid->pnpId.data());
+ // ASCII text should be used as fallback if display name and serial number are missing.
+ EXPECT_EQ("121AT11-801", edid->displayName);
+
+ edid = parseEdid(asDisplayIdentificationData(kExternalEdid));
+ ASSERT_TRUE(edid);
+ EXPECT_EQ(0x22f0u, edid->manufacturerId);
+ EXPECT_STREQ("HWP", edid->pnpId.data());
+ EXPECT_EQ("HP ZR30w", edid->displayName);
+
+ edid = parseEdid(asDisplayIdentificationData(kExternalEedid));
+ ASSERT_TRUE(edid);
+ EXPECT_EQ(0x4c2du, edid->manufacturerId);
+ EXPECT_STREQ("SAM", edid->pnpId.data());
+ EXPECT_EQ("SAMSUNG", edid->displayName);
+}
+
+TEST(DisplayIdentificationTest, parseInvalidEdid) {
+ EXPECT_FALSE(isEdid({}));
+ EXPECT_FALSE(parseEdid({}));
+
+ // Display name must be printable.
+ auto data = asDisplayIdentificationData(kExternalEdid);
+ data[97] = '\x1b';
+ auto edid = parseEdid(data);
+ ASSERT_TRUE(edid);
+ // Serial number should be used as fallback if display name is invalid.
+ EXPECT_EQ("CN4202137Q", edid->displayName);
+
+ // Parsing should succeed even if EDID is truncated.
+ data.pop_back();
+ edid = parseEdid(data);
+ ASSERT_TRUE(edid);
+ EXPECT_EQ("CN4202137Q", edid->displayName);
+}
+
+TEST(DisplayIdentificationTest, getPnpId) {
+ EXPECT_FALSE(getPnpId(0));
+ EXPECT_FALSE(getPnpId(static_cast<uint16_t>(-1)));
+
+ EXPECT_STREQ("SEC", getPnpId(0x4ca3u).value_or(PnpId{}).data());
+ EXPECT_STREQ("HWP", getPnpId(0x22f0u).value_or(PnpId{}).data());
+ EXPECT_STREQ("SAM", getPnpId(0x4c2du).value_or(PnpId{}).data());
+}
+
+TEST(DisplayIdentificationTest, generateDisplayId) {
+ const auto primaryId = generateDisplayId(0, asDisplayIdentificationData(kInternalEdid));
+ ASSERT_TRUE(primaryId);
+
+ const auto secondaryId = generateDisplayId(1, asDisplayIdentificationData(kExternalEdid));
+ ASSERT_TRUE(secondaryId);
+
+ const auto tertiaryId = generateDisplayId(2, asDisplayIdentificationData(kExternalEedid));
+ ASSERT_TRUE(tertiaryId);
+
+ // Display IDs should be unique.
+ EXPECT_NE(primaryId, secondaryId);
+ EXPECT_NE(primaryId, tertiaryId);
+ EXPECT_NE(secondaryId, tertiaryId);
+}
+
+} // namespace android