diff options
author | 2024-11-14 14:14:25 -0500 | |
---|---|---|
committer | 2024-11-16 01:30:59 -0500 | |
commit | f9854d272c816ca2ad2fec085e17c6591721bff9 (patch) | |
tree | 0e57c8df7626ee83481719b73e025f0a0356ba35 /libs/ui/DisplayIdentification.cpp | |
parent | c37c90444774da117f8a4eef14b091f0a54086f2 (diff) |
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
Diffstat (limited to 'libs/ui/DisplayIdentification.cpp')
-rw-r--r-- | libs/ui/DisplayIdentification.cpp | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/libs/ui/DisplayIdentification.cpp b/libs/ui/DisplayIdentification.cpp index 5cdaa71627..8d6f74b605 100644 --- a/libs/ui/DisplayIdentification.cpp +++ b/libs/ui/DisplayIdentification.cpp @@ -249,7 +249,8 @@ std::optional<Edid> parseEdid(const DisplayIdentificationData& edid) { view = view.subspan(kDescriptorOffset); std::string_view displayName; - std::string_view serialNumber; + std::string_view descriptorBlockSerialNumber; + std::optional<uint64_t> hashedDescriptorBlockSNOpt = std::nullopt; std::string_view asciiText; ui::Size preferredDTDPixelSize; ui::Size preferredDTDPhysicalSize; @@ -274,7 +275,10 @@ std::optional<Edid> parseEdid(const DisplayIdentificationData& edid) { asciiText = parseEdidText(descriptor); break; case 0xff: - serialNumber = parseEdidText(descriptor); + descriptorBlockSerialNumber = parseEdidText(descriptor); + hashedDescriptorBlockSNOpt = descriptorBlockSerialNumber.empty() + ? std::nullopt + : ftl::stable_hash(descriptorBlockSerialNumber); break; } } else if (isDetailedTimingDescriptor(view)) { @@ -315,7 +319,7 @@ std::optional<Edid> parseEdid(const DisplayIdentificationData& edid) { if (modelString.empty()) { ALOGW("Invalid EDID: falling back to serial number due to missing display name."); - modelString = serialNumber; + modelString = descriptorBlockSerialNumber; } if (modelString.empty()) { ALOGW("Invalid EDID: falling back to ASCII text due to missing serial number."); @@ -369,6 +373,7 @@ std::optional<Edid> parseEdid(const DisplayIdentificationData& edid) { .manufacturerId = manufacturerId, .productId = productId, .hashedBlockZeroSerialNumberOpt = hashedBlockZeroSNOpt, + .hashedDescriptorBlockSerialNumberOpt = hashedDescriptorBlockSNOpt, .pnpId = *pnpId, .modelHash = modelHash, .displayName = displayName, |