diff --git a/arch/arm/src/efm32/efm32_spi.c b/arch/arm/src/efm32/efm32_spi.c
index 1a67d43068b..8abe5d7aa3b 100644
--- a/arch/arm/src/efm32/efm32_spi.c
+++ b/arch/arm/src/efm32/efm32_spi.c
@@ -169,7 +169,7 @@ struct efm32_spidev_s
   uint8_t mode;              /* Mode 0,1,2,3 */
 #endif
 
-  uint8_t nbits;             /* Width of word in bits (8 or 16) */
+  uint8_t nbits;             /* Width of word in bits (4-16) */
   bool initialized;          /* True: Already initialized */
 };