Add GPU detection for dynamic DDC response time

alin23 · Dec 18, 2019 · 81b95cd · 81b95cd
1 parent f56b16f
commit 81b95cd
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Showing 5 changed files with 23 additions and 7 deletions.
diff --git a/EDIDReader/EDIDReader/main.swift b/EDIDReader/EDIDReader/main.swift
@@ -69,10 +69,12 @@ func printDetails(_ id: CGDirectDisplayID) {
     let sn = CGDisplaySerialNumber(id)
     let model = CGDisplayModelNumber(id)
     let vendor = CGDisplayVendorNumber(id)
+    let metalDevice = CGDirectDisplayCopyCurrentMetalDevice(id)
 
     print("    S/N: \(sn)")
     print("    Model Number: \(model))")
     print("    Vendor: \(vendor)\n")
+    print("    GPU: \(metalDevice?.name ?? "")\n")
 
     let idData = DDC.getDisplayIdentificationData(displayID: id)
     let name = DDC.getDisplayName(for: id)

diff --git a/Lunar/Base.lproj/Main.storyboard b/Lunar/Base.lproj/Main.storyboard
@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.Cocoa.Storyboard.XIB" version="3.0" toolsVersion="15505" targetRuntime="MacOSX.Cocoa" propertyAccessControl="none" useAutolayout="YES">
+<document type="com.apple.InterfaceBuilder3.Cocoa.Storyboard.XIB" version="3.0" toolsVersion="15702" targetRuntime="MacOSX.Cocoa" propertyAccessControl="none" useAutolayout="YES">
     <dependencies>
         <deployment identifier="macosx"/>
-        <plugIn identifier="com.apple.InterfaceBuilder.CocoaPlugin" version="15505"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.CocoaPlugin" version="15702"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
     <scenes>
@@ -65,7 +65,7 @@
                                             <attributedString key="attributedTitle"/>
                                             <modifierMask key="keyEquivalentModifierMask"/>
                                         </menuItem>
-                                        <menuItem title="Read Monitor Brightness Periodically" id="5DH-eD-imY">
+                                        <menuItem title="Read External Monitor Brightness Periodically" id="5DH-eD-imY">
                                             <attributedString key="attributedTitle"/>
                                             <modifierMask key="keyEquivalentModifierMask"/>
                                             <connections>

diff --git a/Lunar/DDC.c b/Lunar/DDC.c
@@ -351,7 +351,7 @@ bool DDCWrite(CGDirectDisplayID displayID, struct DDCWriteCommand* write, CFMuta
     return result;
 }
 
-bool DDCRead(CGDirectDisplayID displayID, struct DDCReadCommand* read, CFMutableDictionaryRef displayUUIDByEDID)
+bool DDCRead(CGDirectDisplayID displayID, struct DDCReadCommand* read, CFMutableDictionaryRef displayUUIDByEDID, long ddcMinReplyDelay)
 {
     IOI2CRequest request;
     UInt8 reply_data[11] = {};
@@ -366,7 +366,7 @@ bool DDCRead(CGDirectDisplayID displayID, struct DDCReadCommand* read, CFMutable
         request.sendTransactionType = kIOI2CSimpleTransactionType;
         request.sendBuffer = (vm_address_t)&data[0];
         request.sendBytes = 5;
-        request.minReplyDelay = 30 * kMillisecondScale;
+        request.minReplyDelay = ddcMinReplyDelay * kNanosecondScale;
 
         data[0] = 0x51;
         data[1] = 0x82;

diff --git a/Lunar/DDC.h b/Lunar/DDC.h
@@ -256,7 +256,7 @@ struct EDID {
 
 bool logToFile(char* format, ...);
 bool DDCWrite(CGDirectDisplayID displayID, struct DDCWriteCommand *write, CFMutableDictionaryRef displayUUIDByEDID);
-bool DDCRead(CGDirectDisplayID displayID, struct DDCReadCommand *read, CFMutableDictionaryRef displayUUIDByEDID);
+bool DDCRead(CGDirectDisplayID displayID, struct DDCReadCommand *read, CFMutableDictionaryRef displayUUIDByEDID, long ddcMinReplyDelay);
 bool EDIDTest(CGDirectDisplayID displayID, struct EDID *edid, uint8_t edidData[256], CFMutableDictionaryRef displayUUIDByEDID);
 UInt32 SupportedTransactionType(void);
 void setDebugMode(UInt8);

diff --git a/Lunar/DDC/DDC.swift b/Lunar/DDC/DDC.swift
@@ -16,6 +16,10 @@ let MAX_WRITE_DURATION_MS = 2000
 let MAX_READ_FAULTS = 10
 let MAX_WRITE_FAULTS = 20
 
+let DDC_MIN_REPLY_DELAY_AMD = 30_000_000
+let DDC_MIN_REPLY_DELAY_INTEL = 1
+let DDC_MIN_REPLY_DELAY_NVIDIA = 1
+
 struct DDCReadResult {
     var controlID: ControlID
     var maxValue: UInt8
@@ -256,8 +260,18 @@ class DDC {
         let displayUUIDByEDIDCopy = displayUUIDByEDID
         let nsDisplayUUIDByEDID = NSMutableDictionary(dictionary: displayUUIDByEDIDCopy)
 
+        let metalDevice = CGDirectDisplayCopyCurrentMetalDevice(displayID)
+        var ddcDelay = DDC_MIN_REPLY_DELAY_INTEL
+        if let gpu = metalDevice {
+            if gpu.name.lowercased().contains("amd") {
+                ddcDelay = DDC_MIN_REPLY_DELAY_AMD
+            } else if gpu.name.lowercased().contains("nvidia") {
+                ddcDelay = DDC_MIN_REPLY_DELAY_NVIDIA
+            }
+        }
+
         let readStartedAt = DispatchTime.now()
-        DDCRead(displayID, &command, nsDisplayUUIDByEDID as CFMutableDictionary)
+        DDCRead(displayID, &command, nsDisplayUUIDByEDID as CFMutableDictionary, ddcDelay)
         let readMs = (DispatchTime.now().rawValue - readStartedAt.rawValue) / 1_000_000
         if readMs > MAX_READ_DURATION_MS {
             log.debug("Reading \(controlID) took too long: \(readMs)ms", context: displayID)