diff --git a/lib/lpc43xx/ssp.c b/lib/lpc43xx/ssp.c
index d4e9b2d7..91e03241 100644
--- a/lib/lpc43xx/ssp.c
+++ b/lib/lpc43xx/ssp.c
@@ -35,27 +35,6 @@ LGPL License Terms @ref lgpl_license
 #include <libopencm3/lpc43xx/ssp.h>
 #include <libopencm3/lpc43xx/cgu.h>
 
-#define CGU_SRC_32K			0x00
-#define CGU_SRC_IRC			0x01
-#define CGU_SRC_ENET_RX		0x02
-#define CGU_SRC_ENET_TX		0x03
-#define CGU_SRC_GP_CLKIN	0x04
-#define CGU_SRC_XTAL		0x06
-#define CGU_SRC_PLL0USB		0x07
-#define CGU_SRC_PLL0AUDIO	0x08
-#define CGU_SRC_PLL1		0x09
-#define CGU_SRC_IDIVA		0x0C
-#define CGU_SRC_IDIVB		0x0D
-#define CGU_SRC_IDIVC		0x0E
-#define CGU_SRC_IDIVD		0x0F
-#define CGU_SRC_IDIVE		0x10
-
-#define CGU_AUTOBLOCK_CLOCK_BIT	11
-#define CGU_BASE_CLK_SEL_SHIFT	24   /* clock source selection (5 bits) */
-
-/* Local declarations. */
-void ssp_wait_until_not_busy(ssp_num_t ssp_num);
-
 /* Disable SSP */
 void ssp_disable(ssp_num_t ssp_num)
 {
@@ -93,8 +72,9 @@ void ssp_init(ssp_num_t ssp_num,
 	}
 
 	/* use PLL1 as clock source for SSP1 */
-	CGU_BASE_SSP1_CLK = (CGU_SRC_PLL1<<CGU_BASE_CLK_SEL_SHIFT) |
-			    (1<<CGU_AUTOBLOCK_CLOCK_BIT);
+	CGU_BASE_SSP1_CLK =
+		  CGU_BASE_SSP1_CLK_CLK_SEL(CGU_SRC_PLL1)
+		| CGU_BASE_SSP1_CLK_AUTOBLOCK;
 
 	/* Disable SSP before to configure it */
 	SSP_CR1(ssp_port) = 0x0;