diff --git a/wpilibc/src/main/native/include/frc/SPI.h b/wpilibc/src/main/native/include/frc/SPI.h
index 0d5b468cf3..153c98b794 100644
--- a/wpilibc/src/main/native/include/frc/SPI.h
+++ b/wpilibc/src/main/native/include/frc/SPI.h
@@ -28,10 +28,12 @@ class SPI {
  public:
   enum Port { kOnboardCS0 = 0, kOnboardCS1, kOnboardCS2, kOnboardCS3, kMXP };
   enum Mode {
-    kMode0 = HAL_SPI_kMode0,
-    kMode1 = HAL_SPI_kMode1,
-    kMode2 = HAL_SPI_kMode2,
-    kMode3 = HAL_SPI_kMode3
+    kMode0 = HAL_SPI_kMode0, /*!< Clock idle low, data sampled on rising edge */
+    kMode1 =
+        HAL_SPI_kMode1, /*!< Clock idle low, data sampled on falling edge */
+    kMode2 =
+        HAL_SPI_kMode2, /*!< Clock idle high, data sampled on falling edge */
+    kMode3 = HAL_SPI_kMode3 /*!< Clock idle high, data sampled on rising edge */
   };
 
   /**
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/SPI.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/SPI.java
index aedab28a30..489ed832cd 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/SPI.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/SPI.java
@@ -29,9 +29,13 @@ public class SPI implements AutoCloseable {
   }
 
   public enum Mode {
+    /** Clock idle low, data sampled on rising edge. */
     kMode0(SPIJNI.SPI_MODE0),
+    /** Clock idle low, data sampled on falling edge. */
     kMode1(SPIJNI.SPI_MODE1),
+    /** Clock idle high, data sampled on falling edge. */
     kMode2(SPIJNI.SPI_MODE2),
+    /** Clock idle high, data sampled on rising edge. */
     kMode3(SPIJNI.SPI_MODE3);
 
     public final int value;