Fix ASUS Z170 EC temperature read returning zero values (#2153)

* Fix ASUS Z170 EC temperature read returning zero values
Adjust EC read logic so temperature registers (PCH, T_SENSOR, VRM)
return valid values on ASUS Z170 boards in user-mode.
Verified with RWEverything and HWiNFO.

* merge back to inter100,
Use IBF clearing fallback when OBF unsupported

* Fix formatting of CrOS enum entry

* Update WindowsEmbeddedControllerIO.cs

---------

Co-authored-by: PhyxionNL <7643972+PhyxionNL@users.noreply.github.com>

LibreHardwareMonitorLib/Hardware/Motherboard/Identification.cs

@@ -391,6 +391,8 @@ internal class Identification
                 return Model.ROG_ZENITH_II_EXTREME;
             case var _ when name.Equals("Z170-A", StringComparison.OrdinalIgnoreCase):
                 return Model.Z170_A;
+            case var _ when name.Equals("Z170 PRO GAMING", StringComparison.OrdinalIgnoreCase):
+                return Model.Z170_PRO_GAMING;
             case var _ when name.Equals("B150M-C", StringComparison.OrdinalIgnoreCase):
                 return Model.B150M_C;
             case var _ when name.Equals("B150M-C D3", StringComparison.OrdinalIgnoreCase):

LibreHardwareMonitorLib/Hardware/Motherboard/Lpc/EC/EmbeddedController.cs

@@ -257,6 +257,11 @@ public abstract class EmbeddedController : Hardware
             ECSensor.FanWaterPump,
             ECSensor.CurrCPU,
             ECSensor.VoltageCPU),
+        new(Model.Z170_PRO_GAMING,
+            BoardFamily.Intel100,
+            ECSensor.TempChipset,
+            ECSensor.TempVrm,
+            ECSensor.TempTSensor),
         new(Model.PRIME_Z690_A,
             BoardFamily.Intel600,
             ECSensor.TempTSensor,
@@ -398,6 +403,7 @@ public abstract class EmbeddedController : Hardware
             BoardFamily.Intel100, new Dictionary<ECSensor, EmbeddedControllerSource>
             {
                 { ECSensor.TempChipset, new EmbeddedControllerSource("Chipset", SensorType.Temperature, 0x003a) },
+                { ECSensor.TempVrm, new EmbeddedControllerSource("VRM", SensorType.Temperature, 0x003e) },
                 { ECSensor.TempTSensor, new EmbeddedControllerSource("T Sensor", SensorType.Temperature, 0x003d, blank: -40) },
                 { ECSensor.FanWaterPump, new EmbeddedControllerSource("Water Pump", SensorType.Fan, 0x00bc, 2) },
                 { ECSensor.CurrCPU, new EmbeddedControllerSource("CPU", SensorType.Current, 0x00f4) },

LibreHardwareMonitorLib/Hardware/Motherboard/Lpc/EC/WindowsEmbeddedControllerIO.cs

@@ -3,7 +3,6 @@
 // Copyright (C) LibreHardwareMonitor and Contributors.
 // All Rights Reserved.
 
-using System;
 using System.Diagnostics;
 using System.Threading;
 using LibreHardwareMonitor.PawnIo;
@@ -25,12 +24,12 @@ public class WindowsEmbeddedControllerIO : IEmbeddedControllerIO
 
     // implementation
     private const int WaitSpins = 50;
+
+    private readonly LpcAcpiEc _pawnModule;
     private bool _disposed;
 
     private int _waitReadFailures;
 
-    private readonly LpcAcpiEc _pawnModule;
-
     public WindowsEmbeddedControllerIO()
     {
         _pawnModule = new LpcAcpiEc();
@@ -62,22 +61,13 @@ public class WindowsEmbeddedControllerIO : IEmbeddedControllerIO
             {
                 bank = SwitchBank(regBank);
             }
+
             data[i] = ReadByte(regIndex);
         }
 
         SwitchBank(prevBank);
     }
 
-    private byte ReadByte(byte register)
-    {
-        return ReadLoop<byte>(register, ReadByteOp);
-    }
-
-    private void WriteByte(byte register, byte value)
-    {
-        WriteLoop(register, value, WriteByteOp);
-    }
-
     public void Dispose()
     {
         if (!_disposed)
@@ -88,6 +78,16 @@ public class WindowsEmbeddedControllerIO : IEmbeddedControllerIO
         }
     }
 
+    private byte ReadByte(byte register)
+    {
+        return ReadLoop<byte>(register, ReadByteOp);
+    }
+
+    private void WriteByte(byte register, byte value)
+    {
+        WriteLoop(register, value, WriteByteOp);
+    }
+
     private byte SwitchBank(byte bank)
     {
         byte previous = ReadByte(0xFF);
@@ -145,10 +145,31 @@ public class WindowsEmbeddedControllerIO : IEmbeddedControllerIO
             return true;
         }
 
-        if (WaitForStatus(Status.OutputBufferFull, true))
+        // Try OBF with reduced timeout
+        for (int i = 0; i < MaxRetries; i++)
         {
-            _waitReadFailures = 0;
-            return true;
+            byte status = ReadIOPort(Port.Command);
+            if ((status & (byte)Status.OutputBufferFull) != 0)
+            {
+                _waitReadFailures = 0;
+                return true;
+            }
+
+            Thread.Sleep(1);
+        }
+
+        // ASUS workaround: Wait for IBF to clear instead of OBF
+        // Testing on Z170 Pro Gaming shows IBF clears in 1-3ms when data is ready
+        for (int i = 0; i < WaitSpins; i++)
+        {
+            byte status = ReadIOPort(Port.Command);
+            if ((status & (byte)Status.InputBufferFull) == 0)
+            {
+                _waitReadFailures = 0;
+                return true;
+            }
+
+            Thread.Sleep(1);
         }
 
         _waitReadFailures++;
@@ -170,45 +191,6 @@ public class WindowsEmbeddedControllerIO : IEmbeddedControllerIO
         _pawnModule.WritePort((byte)port, datum);
     }
 
-    public class BusMutexLockingFailedException : EmbeddedController.IOException
-    {
-        public BusMutexLockingFailedException()
-            : base("could not lock ISA bus mutex")
-        { }
-    }
-
-    private delegate bool ReadOp<TParam>(byte register, out TParam p);
-
-    private delegate bool WriteOp<in TParam>(byte register, TParam p);
-
-    // see the ACPI specification chapter 12
-    private enum Port : byte
-    {
-        Command = 0x66,
-        Data = 0x62
-    }
-
-    private enum Command : byte
-    {
-        Read = 0x80, // RD_EC
-        Write = 0x81, // WR_EC
-        BurstEnable = 0x82, // BE_EC
-        BurstDisable = 0x83, // BD_EC
-        Query = 0x84 // QR_EC
-    }
-
-    private enum Status : byte
-    {
-        OutputBufferFull = 0x01, // EC_OBF
-        InputBufferFull = 0x02, // EC_IBF
-        Command = 0x08, // CMD
-        BurstMode = 0x10, // BURST
-        SciEventPending = 0x20, // SCI_EVT
-        SmiEventPending = 0x40 // SMI_EVT
-    }
-
-    #region Read/Write ops
-
     protected bool ReadByteOp(byte register, out byte value)
     {
         if (WaitWrite())
@@ -250,5 +232,39 @@ public class WindowsEmbeddedControllerIO : IEmbeddedControllerIO
         return false;
     }
 
-    #endregion
+    public class BusMutexLockingFailedException : EmbeddedController.IOException
+    {
+        public BusMutexLockingFailedException() : base("could not lock ISA bus mutex")
+        { }
+    }
+
+    private delegate bool ReadOp<TParam>(byte register, out TParam p);
+
+    private delegate bool WriteOp<in TParam>(byte register, TParam p);
+
+    // see the ACPI specification chapter 12
+    private enum Port : byte
+    {
+        Command = 0x66,
+        Data = 0x62
+    }
+
+    private enum Command : byte
+    {
+        Read = 0x80, // RD_EC
+        Write = 0x81, // WR_EC
+        BurstEnable = 0x82, // BE_EC
+        BurstDisable = 0x83, // BD_EC
+        Query = 0x84 // QR_EC
+    }
+
+    private enum Status : byte
+    {
+        OutputBufferFull = 0x01, // EC_OBF
+        InputBufferFull = 0x02, // EC_IBF
+        Command = 0x08, // CMD
+        BurstMode = 0x10, // BURST
+        SciEventPending = 0x20, // SCI_EVT
+        SmiEventPending = 0x40 // SMI_EVT
+    }
 }

LibreHardwareMonitorLib/Hardware/Motherboard/Model.cs

@@ -115,6 +115,7 @@ public enum Model
     TUF_X470_PLUS_GAMING,
     TUF_GAMING_X870_PLUS_WIFI,
     Z170_A,
+    Z170_PRO_GAMING,
     B150M_C,
     B150M_C_D3,
     TUF_GAMING_X570_PLUS_WIFI,