diff --git a/os/hal/platforms/STM32/i2c_lld.h b/os/hal/platforms/STM32/i2c_lld.h
index 51c975c37..d9cd40915 100644
--- a/os/hal/platforms/STM32/i2c_lld.h
+++ b/os/hal/platforms/STM32/i2c_lld.h
@@ -165,8 +165,8 @@ struct I2CDriver{
 
   size_t                txbytes;    /*!< Number of bytes to be transmitted. */
   size_t                rxbytes;    /*!< Number of bytes to be received. */
-  uint8_t               *rxbuff_p;   /*!< Pointer to the current byte in slave rx buffer. */
-  uint8_t               *txbuff_p;   /*!< Pointer to the current byte in slave tx buffer. */
+  uint8_t               *rxbuff_p;  /*!< Pointer to the current byte in slave rx buffer. */
+  uint8_t               *txbuff_p;  /*!< Pointer to the current byte in slave tx buffer. */
 
   i2cflags_t            errors;     /*!< Error flags.*/
   i2cflags_t            flags;      /*!< State flags.*/
diff --git a/testhal/STM32/I2C/lis3.c b/testhal/STM32/I2C/lis3.c
index 9ce1532a6..c50d7e9a6 100644
--- a/testhal/STM32/I2C/lis3.c
+++ b/testhal/STM32/I2C/lis3.c
@@ -14,7 +14,7 @@
 #include "lis3.h"
 
 
-// buffers
+/* buffers */
 static i2cblock_t accel_rx_data[ACCEL_RX_DEPTH];
 static i2cblock_t accel_tx_data[ACCEL_TX_DEPTH];
 
@@ -64,7 +64,7 @@ static msg_t I2CAccelThread(void *arg) {
 /* This callback raise up when transfer finished */
 static void i2c_lis3_cb(I2CDriver *i2cp, const I2CSlaveConfig *i2cscfg){
   (void) i2cp;
-  // only wake up processing thread
+  /* only wake up processing thread */
   if (i2c_accel_tp != NULL) {
     i2c_accel_tp->p_msg = (msg_t)i2cscfg;
     chSchReadyI(i2c_accel_tp);
@@ -73,7 +73,7 @@ static void i2c_lis3_cb(I2CDriver *i2cp, const I2CSlaveConfig *i2cscfg){
 }
 
 
-// Accelerometer lis3lv02dq config
+/* Accelerometer lis3lv02dq config */
 static const I2CSlaveConfig lis3 = {
 	i2c_lis3_cb,
   i2c_lis3_error_cb,
@@ -103,10 +103,10 @@ int init_lis3(void){
     chThdSleepMilliseconds(1);
 
 #define TXBYTES 4
-#define RXBYTES 0 //set to 0 because we need only transmit
+#define RXBYTES 0 /* set to 0 because we need only transmit */
 
   /* configure accelerometer */
-  lis3.txbuf[0] = ACCEL_CTRL_REG1 | AUTO_INCREMENT_BIT; // register address
+  lis3.txbuf[0] = ACCEL_CTRL_REG1 | AUTO_INCREMENT_BIT; /* register address */
   lis3.txbuf[1] = 0b11100111;
   lis3.txbuf[2] = 0b01000001;
   lis3.txbuf[3] = 0b00000000;
diff --git a/testhal/STM32/I2C/max1236.c b/testhal/STM32/I2C/max1236.c
index 7ea184b14..13779b99a 100644
--- a/testhal/STM32/I2C/max1236.c
+++ b/testhal/STM32/I2C/max1236.c
@@ -10,10 +10,10 @@
 
 #include "max1236.h"
 
-// Data buffers
+/* Data buffers */
 static i2cblock_t max1236_rx_data[MAX1236_RX_DEPTH];
 static i2cblock_t max1236_tx_data[MAX1236_TX_DEPTH];
-// ADC results
+/* ADC results */
 static uint16_t ch1 = 0, ch2 = 0, ch3 = 0, ch4 = 0;
 
 
@@ -37,7 +37,7 @@ static void i2c_max1236_cb(I2CDriver *i2cp, const I2CSlaveConfig *i2cscfg){
 }
 
 
-// ADC maxim MAX1236 config
+/* ADC maxim MAX1236 config */
 
 static const I2CSlaveConfig max1236 = {
 		i2c_max1236_cb,
@@ -56,11 +56,11 @@ void init_max1236(void){
   /* this data we must send via IC to setup ADC */
 #define RXBYTES 0
 #define TXBYTES 2
-  max1236.txbuf[0] = 0b10000011; // config register content. Consult datasheet
-  max1236.txbuf[1] = 0b00000111; // config register content. Consult datasheet
+  max1236.txbuf[0] = 0b10000011; /* config register content. Consult datasheet */
+  max1236.txbuf[1] = 0b00000111; /* config register content. Consult datasheet */
 
 
-  // transmit out 2 bytes
+  /* transmit out 2 bytes */
   i2cAcquireBus(&I2CD2);
   i2cMasterTransmit(&I2CD2, &max1236, max1236_addr, TXBYTES, RXBYTES);
   while(I2CD2.id_state != I2C_READY){
diff --git a/testhal/STM32/I2C/tmp75.c b/testhal/STM32/I2C/tmp75.c
index 6a8fe603d..0833e47c1 100644
--- a/testhal/STM32/I2C/tmp75.c
+++ b/testhal/STM32/I2C/tmp75.c
@@ -12,13 +12,13 @@
 #include "tmp75.h"
 
 
-// input buffer
+/* input buffer */
 static i2cblock_t tmp75_rx_data[TMP75_RX_DEPTH];
 static i2cblock_t tmp75_tx_data[TMP75_TX_DEPTH];
-// temperature value
+/* temperature value */
 static int16_t temperature = 0;
 
-// Simple error trap
+/* Simple error trap */
 static void i2c_tmp75_error_cb(I2CDriver *i2cp, const I2CSlaveConfig *i2cscfg){
   (void)i2cscfg;
   int status = 0;
@@ -33,7 +33,7 @@ static void i2c_tmp75_cb(I2CDriver *i2cp, const I2CSlaveConfig *i2cscfg){
   temperature = (i2cscfg->rxbuf[0] << 8) + i2cscfg->rxbuf[1];
 }
 
-// Fill TMP75 config.
+/* Fill TMP75 config. */
 static const I2CSlaveConfig tmp75 = {
     i2c_tmp75_cb,
     i2c_tmp75_error_cb,
@@ -45,8 +45,8 @@ static const I2CSlaveConfig tmp75 = {
 
 /* This is main function. */
 void request_temperature(void){
-#define TXBYTES 0  // set to zero because we need only reading
-#define RXBYTES 2  // we need to read 2 bytes
+#define TXBYTES 0  /* set to zero because we need only reading */
+#define RXBYTES 2  /* we need to read 2 bytes */
 
   i2cAcquireBus(&I2CD2);
   i2cMasterReceive(&I2CD2, &tmp75, tmp75_addr, RXBYTES);