diff --git a/nuttx/arch/arm/src/lpc17xx/chip/lpc178x_iocon.h b/nuttx/arch/arm/src/lpc17xx/chip/lpc178x_iocon.h
index a3c247caf2..ca4ab6b1d7 100755
--- a/nuttx/arch/arm/src/lpc17xx/chip/lpc178x_iocon.h
+++ b/nuttx/arch/arm/src/lpc17xx/chip/lpc178x_iocon.h
@@ -52,7 +52,7 @@
 
 /* Register offsets *****************************************************************/
 
-#define LPC17_IOCON_PP_OFFSET(p)    ((p) << 2)
+#define LPC17_IOCON_PP_OFFSET(p)    ((unsigned int)(p) << 2)
 #define LPC17_IOCON_PP0_OFFSET      (0x0000) /* IOCON Port(n) register 0  */
 #define LPC17_IOCON_PP1_OFFSET      (0x0004) /* IOCON Port(n) register 1  */
 #define LPC17_IOCON_PP2_OFFSET      (0x0008) /* IOCON Port(n) register 2  */
@@ -88,7 +88,7 @@
 
 /* Register addresses ***************************************************************/
 
-#define LPC17_IOCON_P_BASE(b)       (LPC17_IOCON_BASE + ((b) << 7))
+#define LPC17_IOCON_P_BASE(b)       (LPC17_IOCON_BASE + (unsigned int(b) << 7))
 #define LPC17_IOCON_P0_BASE         (LPC17_IOCON_BASE + 0x0000)
 #define LPC17_IOCON_P1_BASE         (LPC17_IOCON_BASE + 0x0080)
 #define LPC17_IOCON_P2_BASE         (LPC17_IOCON_BASE + 0x0100)
diff --git a/nuttx/arch/arm/src/lpc17xx/lpc17_gpio.c b/nuttx/arch/arm/src/lpc17xx/lpc17_gpio.c
index ece6adc5ff..e3085ff78e 100644
--- a/nuttx/arch/arm/src/lpc17xx/lpc17_gpio.c
+++ b/nuttx/arch/arm/src/lpc17xx/lpc17_gpio.c
@@ -110,44 +110,6 @@ const uint32_t g_ioconport[GPIO_NPORTS] =
   LPC17_IOCON_P4,
   LPC17_IOCON_P5
 }
-
-/* Register offsets */
-
-const uint32_t g_ioconpin[32] =
-{
-  LPC17_IOCON_PP0_OFFSET,
-  LPC17_IOCON_PP1_OFFSET,
-  LPC17_IOCON_PP2_OFFSET,
-  LPC17_IOCON_PP3_OFFSET,
-  LPC17_IOCON_PP4_OFFSET,
-  LPC17_IOCON_PP5_OFFSET,
-  LPC17_IOCON_PP6_OFFSET,
-  LPC17_IOCON_PP7_OFFSET,
-  LPC17_IOCON_PP8_OFFSET,
-  LPC17_IOCON_PP9_OFFSET,
-  LPC17_IOCON_PP10_OFFSET,
-  LPC17_IOCON_PP11_OFFSET,
-  LPC17_IOCON_PP12_OFFSET,
-  LPC17_IOCON_PP13_OFFSET,
-  LPC17_IOCON_PP14_OFFSET,
-  LPC17_IOCON_PP15_OFFSET,
-  LPC17_IOCON_PP16_OFFSET,
-  LPC17_IOCON_PP17_OFFSET,
-  LPC17_IOCON_PP18_OFFSET,
-  LPC17_IOCON_PP19_OFFSET,
-  LPC17_IOCON_PP20_OFFSET,
-  LPC17_IOCON_PP21_OFFSET,
-  LPC17_IOCON_PP22_OFFSET,
-  LPC17_IOCON_PP23_OFFSET,
-  LPC17_IOCON_PP24_OFFSET,
-  LPC17_IOCON_PP25_OFFSET,
-  LPC17_IOCON_PP26_OFFSET,
-  LPC17_IOCON_PP27_OFFSET,
-  LPC17_IOCON_PP28_OFFSET,
-  LPC17_IOCON_PP29_OFFSET,
-  LPC17_IOCON_PP30_OFFSET,
-  LPC17_IOCON_PP31_OFFSET
-};
 #endif
 
 /* Port 0 and Port 2 can provide a single interrupt for any combination of
@@ -434,7 +396,7 @@ static int lpc17_configiocon(unsigned int port, unsigned int pin,
   uint32_t regaddr;
   uint32_t regval;
 
-  regaddr = (g_ioconbase[port] + g_ioconpin[pin]);
+  regaddr = (g_ioconbase[port] + LPC17_IOCON_PP_OFFSET(pin));
   regval  = getreg32(regaddr);
   regval &= value;
   putreg32(regval, regaddr);
diff --git a/nuttx/arch/arm/src/lpc17xx/lpc17_gpio.h b/nuttx/arch/arm/src/lpc17xx/lpc17_gpio.h
index 62bf2d0188..99a0b67e94 100644
--- a/nuttx/arch/arm/src/lpc17xx/lpc17_gpio.h
+++ b/nuttx/arch/arm/src/lpc17xx/lpc17_gpio.h
@@ -354,7 +354,6 @@ EXTERN const uint32_t g_hipinmode[GPIO_NPORTS];
 EXTERN const uint32_t g_odmode[GPIO_NPORTS];
 #ifdef LPC178x
 EXTERN const uint32_t g_ioconport[GPIO_NPORTS];
-EXTERN const uint32_t g_ioconpin[32];
 #endif
 
 /****************************************************************************