diff --git a/cpu/stm32l1/include/periph_cpu.h b/cpu/stm32l1/include/periph_cpu.h
new file mode 100644
index 0000000000..88865f061b
--- /dev/null
+++ b/cpu/stm32l1/include/periph_cpu.h
@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2015 Freie Universität Berlin
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup         cpu_stm32l1
+ * @{
+ *
+ * @file
+ * @brief           CPU specific definitions for internal peripheral handling
+ *
+ * @author          Hauke Petersen <hauke.peterse@fu-berlin.de>
+ */
+
+#ifndef PERIPH_CPU_H_
+#define PERIPH_CPU_H_
+
+#include "periph/dev_enums.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* nothing defined here, yet */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* PERIPH_CPU_H_ */
+/** @} */
diff --git a/cpu/stm32l1/periph/gpio.c b/cpu/stm32l1/periph/gpio.c
index 5901373c27..251997dfb2 100644
--- a/cpu/stm32l1/periph/gpio.c
+++ b/cpu/stm32l1/periph/gpio.c
@@ -24,9 +24,6 @@
 #include "periph/gpio.h"
 #include "periph_conf.h"
 
-/* guard file in case no GPIO devices are defined */
-#if GPIO_NUMOF
-
 typedef struct {
     gpio_cb_t cb;
     void *arg;
@@ -190,7 +187,7 @@ static const IRQn_Type gpio_irq_map[GPIO_NUMOF] = {
 #endif
 };
 
-int gpio_init_out(gpio_t dev, gpio_pp_t pullup)
+int gpio_init(gpio_t dev, gpio_dir_t dir, gpio_pp_t pullup)
 {
     GPIO_TypeDef *port;
     uint8_t pin;
@@ -202,36 +199,22 @@ int gpio_init_out(gpio_t dev, gpio_pp_t pullup)
     port = gpio_port_map[dev];
     pin = gpio_pin_map[dev];
 
-    port->MODER &= ~(2 << (2 * pin));           /* set pin to output mode */
-    port->MODER |= (1 << (2 * pin));
-    port->OTYPER &= ~(1 << pin);                /* set to push-pull configuration */
-    port->OSPEEDR |= (3 << (2 * pin));          /* set to high speed */
+    if (dir == GPIO_DIR_OUT) {
+        port->MODER &= ~(2 << (2 * pin));           /* set pin to output mode */
+        port->MODER |= (1 << (2 * pin));
+        port->OTYPER &= ~(1 << pin);                /* set to push-pull configuration */
+        port->OSPEEDR |= (3 << (2 * pin));          /* set to high speed */
+        port->ODR &= ~(1 << pin);                   /* set pin to low signal */
+    }
+    else {
+        port->MODER &= ~(3 << (2 * pin));           /* configure pin as input */
+    }
     port->PUPDR &= ~(3 << (2 * pin));           /* configure push-pull resistors */
     port->PUPDR |= (pullup << (2 * pin));
-    port->ODR &= ~(1 << pin);                   /* set pin to low signal */
 
     return 0; /* all OK */
 }
 
-int gpio_init_in(gpio_t dev, gpio_pp_t pullup)
-{
-    GPIO_TypeDef *port;
-    uint8_t pin;
-
-    if (dev >= GPIO_NUMOF) {
-        return -1;
-    }
-
-    port = gpio_port_map[dev];
-    pin = gpio_pin_map[dev];
-
-    port->MODER &= ~(3 << (2 * pin));           /* configure pin as input */
-    port->PUPDR &= ~(3 << (2 * pin));           /* configure push-pull resistors */
-    port->PUPDR |= (pullup << (2 * pin));
-
-    return 0; /* everything alright here */
-}
-
 int gpio_init_int(gpio_t dev, gpio_pp_t pullup, gpio_flank_t flank, gpio_cb_t cb, void *arg)
 {
     int res;
@@ -244,7 +227,7 @@ int gpio_init_int(gpio_t dev, gpio_pp_t pullup, gpio_flank_t flank, gpio_cb_t cb
     pin = gpio_pin_map[dev];
 
     /* configure pin as input */
-    res = gpio_init_in(dev, pullup);
+    res = gpio_init(dev, GPIO_DIR_IN, pullup);
     if (res < 0) {
         return res;
     }
@@ -583,5 +566,3 @@ void isr_exti15_10(void)
     }
 }
 #endif
-
-#endif /* GPIO_NUMOF */