diff --git a/cpu/sam0_common/periph/i2c.c b/cpu/sam0_common/periph/i2c.c
index 31f1e93676..2adcd4eac0 100644
--- a/cpu/sam0_common/periph/i2c.c
+++ b/cpu/sam0_common/periph/i2c.c
@@ -49,7 +49,7 @@
 #define SERCOM_I2CM_CTRLA_MODE_I2C_MASTER SERCOM_I2CM_CTRLA_MODE(5)
 #endif
 
-static int _start(SercomI2cm *dev, uint16_t addr);
+static int _i2c_start(SercomI2cm *dev, uint16_t addr);
 static inline int _write(SercomI2cm *dev, const uint8_t *data, size_t length,
                          uint8_t stop);
 static inline int _read(SercomI2cm *dev, uint8_t *data, size_t length,
@@ -248,7 +248,7 @@ int i2c_read_bytes(i2c_t dev, uint16_t addr,
 
     if (!(flags & I2C_NOSTART)) {
         /* start transmission and send slave address */
-        ret = _start(bus(dev), (addr << 1) | I2C_READ);
+        ret = _i2c_start(bus(dev), (addr << 1) | I2C_READ);
         if (ret < 0) {
             DEBUG("Start command failed\n");
             return ret;
@@ -289,7 +289,7 @@ int i2c_write_bytes(i2c_t dev, uint16_t addr, const void *data, size_t len,
     }
 
     if (!(flags & I2C_NOSTART)) {
-        ret = _start(bus(dev), (addr<<1));
+        ret = _i2c_start(bus(dev), (addr<<1));
         if (ret < 0) {
             DEBUG("Start command failed\n");
             return ret;
@@ -326,7 +326,7 @@ void _i2c_poweroff(i2c_t dev)
     _syncbusy(bus(dev));
 }
 
-static int _start(SercomI2cm *dev, uint16_t addr)
+static int _i2c_start(SercomI2cm *dev, uint16_t addr)
 {
     /* Wait for hardware module to sync */
     DEBUG("Wait for device to be ready\n");
diff --git a/cpu/stm32/periph/i2c_1.c b/cpu/stm32/periph/i2c_1.c
index 6589981d05..d656d89ae1 100644
--- a/cpu/stm32/periph/i2c_1.c
+++ b/cpu/stm32/periph/i2c_1.c
@@ -74,7 +74,7 @@ static uint32_t hsi_state;
 static inline void _i2c_init(I2C_TypeDef *i2c, uint32_t timing);
 static int _write(I2C_TypeDef *i2c, uint16_t addr, const void *data,
                   size_t length, uint8_t flags, uint32_t cr2_flags);
-static int _start(I2C_TypeDef *i2c, uint32_t cr2, uint8_t flags);
+static int _i2c_start(I2C_TypeDef *i2c, uint32_t cr2, uint8_t flags);
 static int _stop(I2C_TypeDef *i2c);
 static int _wait_isr_set(I2C_TypeDef *i2c, uint32_t mask, uint8_t flags);
 static inline int _wait_for_bus(I2C_TypeDef *i2c);
@@ -227,7 +227,7 @@ int i2c_read_bytes(i2c_t dev, uint16_t address, void *data,
     }
     DEBUG("[i2c] read_bytes: Starting\n");
     /* RELOAD is needed because we don't know the full frame */
-    int ret = _start(i2c, (address << 1) | (length << I2C_CR2_NBYTES_Pos) |
+    int ret = _i2c_start(i2c, (address << 1) | (length << I2C_CR2_NBYTES_Pos) |
                      I2C_CR2_RELOAD | I2C_FLAG_READ, flags);
     if (ret < 0) {
         return ret;
@@ -280,7 +280,7 @@ static int _write(I2C_TypeDef *i2c, uint16_t addr, const void *data,
     if ((i2c->ISR & I2C_ISR_TC) && (flags & I2C_NOSTART)) {
         return -EOPNOTSUPP;
     }
-    int ret = _start(i2c, (addr << 1) | (length << I2C_CR2_NBYTES_Pos) |
+    int ret = _i2c_start(i2c, (addr << 1) | (length << I2C_CR2_NBYTES_Pos) |
                      cr2_flags, flags);
     if (ret < 0) {
         return ret;
@@ -320,7 +320,7 @@ static int _write(I2C_TypeDef *i2c, uint16_t addr, const void *data,
     return _wait_for_bus(i2c);
 }
 
-static int _start(I2C_TypeDef *i2c, uint32_t cr2, uint8_t flags)
+static int _i2c_start(I2C_TypeDef *i2c, uint32_t cr2, uint8_t flags)
 {
     assert(i2c != NULL);
     assert((i2c->ISR & I2C_ISR_BUSY) || !(flags & I2C_NOSTART));
diff --git a/cpu/stm32/periph/i2c_2.c b/cpu/stm32/periph/i2c_2.c
index c260a9cac9..6a1f53e48d 100644
--- a/cpu/stm32/periph/i2c_2.c
+++ b/cpu/stm32/periph/i2c_2.c
@@ -63,7 +63,7 @@
 /* static function definitions */
 static void _init(i2c_t dev);
 static void _i2c_init(I2C_TypeDef *i2c, uint32_t clk, uint32_t ccr);
-static int _start(I2C_TypeDef *dev, uint8_t address_byte, uint8_t flags,
+static int _i2c_start(I2C_TypeDef *dev, uint8_t address_byte, uint8_t flags,
                   size_t length);
 static int _stop(I2C_TypeDef *dev);
 static int _is_sr1_mask_set(I2C_TypeDef *i2c, uint32_t mask, uint8_t flags);
@@ -234,7 +234,7 @@ int i2c_read_bytes(i2c_t dev, uint16_t address, void *data, size_t length,
         !(flags & I2C_NOSTART)) {
         return -EOPNOTSUPP;
     }
-    int ret = _start(i2c, (address << 1) | I2C_FLAG_READ, flags, length);
+    int ret = _i2c_start(i2c, (address << 1) | I2C_FLAG_READ, flags, length);
     if (ret < 0) {
         if (ret == -ETIMEDOUT) {
             _init(dev);
@@ -282,7 +282,7 @@ int i2c_write_bytes(i2c_t dev, uint16_t address, const void *data,
     assert(i2c != NULL);
     DEBUG("[i2c] write_bytes: Starting\n");
     /* Length is 0 in start since we don't need to preset the stop bit */
-    ret = _start(i2c, (address << 1) | I2C_FLAG_WRITE, flags, 0);
+    ret = _i2c_start(i2c, (address << 1) | I2C_FLAG_WRITE, flags, 0);
     if (ret < 0) {
         if (ret == -ETIMEDOUT) {
             _init(dev);
@@ -321,7 +321,7 @@ int i2c_write_bytes(i2c_t dev, uint16_t address, const void *data,
     return _wait_for_bus(i2c);
 }
 
-static int _start(I2C_TypeDef *i2c, uint8_t address_byte, uint8_t flags,
+static int _i2c_start(I2C_TypeDef *i2c, uint8_t address_byte, uint8_t flags,
                   size_t length)
 {
     assert(i2c != NULL);