Make System.Device.Gpio work on Mono (#1095)

src/System.Device.Gpio/System/Device/Gpio/Drivers/RaspberryPi3Driver.cs

@@ -41,7 +41,7 @@ namespace System.Device.Gpio.Drivers
             }
             else
             {
-                _internalDriver = new Windows10Driver();
+                _internalDriver = CreateWindows10GpioDriver();
                 _setSetRegister = (value) => throw new PlatformNotSupportedException();
                 _setClearRegister = (value) => throw new PlatformNotSupportedException();
                 _getSetRegister = () => throw new PlatformNotSupportedException();
@@ -49,6 +49,16 @@ namespace System.Device.Gpio.Drivers
             }
         }
 
+        [MethodImpl(MethodImplOptions.NoInlining)]
+        private static GpioDriver CreateWindows10GpioDriver()
+        {
+            // This wrapper is needed to prevent Mono from loading Windows10Driver
+            // which causes all fields to be loaded - one of such fields is WinRT type which does not
+            // exist on Linux which causes TypeLoadException.
+            // Using NoInlining and no explicit type prevents this from happening.
+            return new Windows10Driver();
+        }
+
         /// <inheritdoc/>
         protected internal override int PinCount => 28;
 

src/System.Device.Gpio/System/Device/I2c/I2cDevice.cs

@@ -2,6 +2,8 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System.Runtime.CompilerServices;
+
 namespace System.Device.I2c
 {
     /// <summary>
@@ -67,7 +69,7 @@ namespace System.Device.I2c
         {
             if (Environment.OSVersion.Platform == PlatformID.Win32NT)
             {
-                return new Windows10I2cDevice(settings);
+                return CreateWindows10I2cDevice(settings);
             }
             else
             {
@@ -75,6 +77,16 @@ namespace System.Device.I2c
             }
         }
 
+        [MethodImpl(MethodImplOptions.NoInlining)]
+        private static I2cDevice CreateWindows10I2cDevice(I2cConnectionSettings settings)
+        {
+            // This wrapper is needed to prevent Mono from loading Windows10I2cDevice
+            // which causes all fields to be loaded - one of such fields is WinRT type which does not
+            // exist on Linux which causes TypeLoadException.
+            // Using NoInlining and no explicit type prevents this from happening.
+            return new Windows10I2cDevice(settings);
+        }
+
         /// <inheritdoc cref="IDisposable.Dispose"/>
         public void Dispose()
         {

src/System.Device.Gpio/System/Device/Pwm/PwmChannel.cs

@@ -2,6 +2,8 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System.Runtime.CompilerServices;
+
 namespace System.Device.Pwm
 {
     /// <summary>
@@ -61,7 +63,7 @@ namespace System.Device.Pwm
         {
             if (Environment.OSVersion.Platform == PlatformID.Win32NT)
             {
-                return new Channels.Windows10PwmChannel(
+                return CreateWindows10PwmChannel(
                     chip,
                     channel,
                     frequency,
@@ -76,5 +78,19 @@ namespace System.Device.Pwm
                     dutyCyclePercentage);
             }
         }
+
+        [MethodImpl(MethodImplOptions.NoInlining)]
+        private static PwmChannel CreateWindows10PwmChannel(int chip, int channel, int frequency, double dutyCyclePercentage)
+        {
+            // This wrapper is needed to prevent Mono from loading Windows10PwmChannel
+            // which causes all fields to be loaded - one of such fields is WinRT type which does not
+            // exist on Linux which causes TypeLoadException.
+            // Using NoInlining and no explicit type prevents this from happening.
+            return new Channels.Windows10PwmChannel(
+                    chip,
+                    channel,
+                    frequency,
+                    dutyCyclePercentage);
+        }
     }
 }

src/System.Device.Gpio/System/Device/Spi/SpiDevice.cs

@@ -2,6 +2,8 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System.Runtime.CompilerServices;
+
 namespace System.Device.Spi
 {
     /// <summary>
@@ -60,7 +62,7 @@ namespace System.Device.Spi
         {
             if (Environment.OSVersion.Platform == PlatformID.Win32NT)
             {
-                return new Windows10SpiDevice(settings);
+                return CreateWindows10SpiDevice(settings);
             }
             else
             {
@@ -68,6 +70,16 @@ namespace System.Device.Spi
             }
         }
 
+        [MethodImpl(MethodImplOptions.NoInlining)]
+        private static SpiDevice CreateWindows10SpiDevice(SpiConnectionSettings settings)
+        {
+            // This wrapper is needed to prevent Mono from loading Windows10SpiDevice
+            // which causes all fields to be loaded - one of such fields is WinRT type which does not
+            // exist on Linux which causes TypeLoadException.
+            // Using NoInlining and no explicit type prevents this from happening.
+            return new Windows10SpiDevice(settings);
+        }
+
         /// <inheritdoc cref="IDisposable.Dispose"/>
         public void Dispose()
         {