diff --git a/include/libopencm3/ethernet/mac_stm32fxx7.h b/include/libopencm3/ethernet/mac_stm32fxx7.h
index 2d7546af..28a0375b 100644
--- a/include/libopencm3/ethernet/mac_stm32fxx7.h
+++ b/include/libopencm3/ethernet/mac_stm32fxx7.h
@@ -719,7 +719,7 @@ void eth_desc_init(uint8_t *buf, uint32_t nTx, uint32_t nRx, uint32_t cTx,
 bool eth_tx(uint8_t *ppkt, uint32_t n);
 bool eth_rx(uint8_t *ppkt, uint32_t *len, uint32_t maxlen);
 
-void eth_init(uint8_t phy,enum eth_clk clock);
+void eth_init(uint8_t phy, enum eth_clk clock);
 void eth_start(void);
 
 void eth_enable_checksum_offload(void);
diff --git a/lib/ethernet/mac_stm32fxx7.c b/lib/ethernet/mac_stm32fxx7.c
index 2ed1b00e..283c40fa 100644
--- a/lib/ethernet/mac_stm32fxx7.c
+++ b/lib/ethernet/mac_stm32fxx7.c
@@ -198,6 +198,7 @@ void eth_start(void)
  *
  * This function will initialize ethernet, set up clocks, and initialize DMA.
  *
+ * @param[in] phy phy id
  * @param[in] clock enum eth_clk Core clock speed
  */
 void eth_init(uint8_t phy, enum eth_clk clock)