diff --git a/drivers/i2c/i2c_read.c b/drivers/i2c/i2c_read.c
index b72523b4eeb..63768a1db0f 100644
--- a/drivers/i2c/i2c_read.c
+++ b/drivers/i2c/i2c_read.c
@@ -71,6 +71,7 @@ int i2c_read(FAR struct i2c_master_s *dev,
 {
   struct i2c_msg_s msg;
   unsigned int flags;
+  int ret;
 
   /* 7- or 10-bit? */
 
@@ -86,5 +87,6 @@ int i2c_read(FAR struct i2c_master_s *dev,
 
   /* Then perform the transfer. */
 
-  return I2C_TRANSFER(dev, &msg, 1);
+  ret = I2C_TRANSFER(dev, &msg, 1);
+  return (ret >= 0) ? OK : ret;
 }
diff --git a/drivers/i2c/i2c_write.c b/drivers/i2c/i2c_write.c
index 30939806c36..d12d70e18f4 100644
--- a/drivers/i2c/i2c_write.c
+++ b/drivers/i2c/i2c_write.c
@@ -71,6 +71,7 @@ int i2c_write(FAR struct i2c_master_s *dev,
               FAR const uint8_t *buffer, int buflen)
 {
   struct i2c_msg_s msg;
+  int ret;
 
   /* Setup for the transfer */
 
@@ -82,5 +83,6 @@ int i2c_write(FAR struct i2c_master_s *dev,
 
   /* Then perform the transfer. */
 
-  return I2C_TRANSFER(dev, &msg, 1);
+  ret = I2C_TRANSFER(dev, &msg, 1);
+  return (ret >= 0) ? OK : ret;
 }
diff --git a/drivers/i2c/i2c_writeread.c b/drivers/i2c/i2c_writeread.c
index d5a09fd9e0b..7527c60ae38 100644
--- a/drivers/i2c/i2c_writeread.c
+++ b/drivers/i2c/i2c_writeread.c
@@ -74,6 +74,7 @@ int i2c_writeread(FAR struct i2c_master_s *dev,
 {
   struct i2c_msg_s msg[2];
   unsigned int flags;
+  int ret;
 
   /* 7- or 10-bit address? */
 
@@ -109,6 +110,7 @@ int i2c_writeread(FAR struct i2c_master_s *dev,
 
   /* Then perform the transfer. */
 
-  return I2C_TRANSFER(dev, msg, 2);
+  ret = I2C_TRANSFER(dev, msg, 2);
+  return (ret >= 0) ? OK : ret;
 }
 
diff --git a/drivers/input/mxt.c b/drivers/input/mxt.c
index 01d11bc63b1..c7364fa3830 100644
--- a/drivers/input/mxt.c
+++ b/drivers/input/mxt.c
@@ -1837,6 +1837,7 @@ static int mxt_hwinitialize(FAR struct mxt_dev_s *priv)
   if (priv->sample == NULL)
     {
       ierr("ERROR: Failed to allocate object table\n");
+      ret = -ENOMEM;
       goto errout_with_objtab;
     }
 
diff --git a/drivers/ioexpander/pca9555.c b/drivers/ioexpander/pca9555.c
index 3da9849dc35..c250fb6e820 100644
--- a/drivers/ioexpander/pca9555.c
+++ b/drivers/ioexpander/pca9555.c
@@ -172,6 +172,7 @@ static inline int pca9555_write(FAR struct pca9555_dev_s *pca,
                                 FAR const uint8_t *wbuffer, int wbuflen)
 {
   struct i2c_msg_s msg;
+  int ret;
 
   /* Setup for the transfer */
 
@@ -183,7 +184,8 @@ static inline int pca9555_write(FAR struct pca9555_dev_s *pca,
 
   /* Then perform the transfer. */
 
-  return I2C_TRANSFER(pca->i2c, &msg, 1);
+  ret = I2C_TRANSFER(pca->i2c, &msg, 1);
+  return (ret >= 0) ? OK : ret;
 }
 
 /****************************************************************************
diff --git a/drivers/ioexpander/pcf8574.c b/drivers/ioexpander/pcf8574.c
index e8fda2986ed..4171017c2f8 100644
--- a/drivers/ioexpander/pcf8574.c
+++ b/drivers/ioexpander/pcf8574.c
@@ -182,6 +182,7 @@ static void pcf8574_lock(FAR struct pcf8574_dev_s *priv)
 static int pcf8574_read(FAR struct pcf8574_dev_s *priv, FAR uint8_t *portval)
 {
   struct i2c_msg_s msg;
+  int ret;
 
   DEBUGASSERT(priv != NULL && priv->i2c != NULL && priv->config != NULL);
 
@@ -195,7 +196,8 @@ static int pcf8574_read(FAR struct pcf8574_dev_s *priv, FAR uint8_t *portval)
 
   /* Then perform the transfer. */
 
-  return I2C_TRANSFER(priv->i2c, &msg, 1);
+  ret = I2C_TRANSFER(priv->i2c, &msg, 1);
+  return (ret >= 0) ? OK : ret;
 }
 
 /****************************************************************************
@@ -212,6 +214,7 @@ static int pcf8574_read(FAR struct pcf8574_dev_s *priv, FAR uint8_t *portval)
 static int pcf8574_write(struct pcf8574_dev_s *priv, uint8_t portval)
 {
   struct i2c_msg_s msg;
+  int ret;
 
   DEBUGASSERT(priv != NULL && priv->i2c != NULL && priv->config != NULL);
 
@@ -225,7 +228,8 @@ static int pcf8574_write(struct pcf8574_dev_s *priv, uint8_t portval)
 
   /* Then perform the transfer. */
 
-  return I2C_TRANSFER(priv->i2c, &msg, 1);
+  ret = I2C_TRANSFER(priv->i2c, &msg, 1);
+  return (ret >= 0) ? OK : ret;
 }
 
 /****************************************************************************
diff --git a/drivers/ioexpander/tca64xx.c b/drivers/ioexpander/tca64xx.c
index 72838d77b20..c23b428cf2f 100644
--- a/drivers/ioexpander/tca64xx.c
+++ b/drivers/ioexpander/tca64xx.c
@@ -342,14 +342,14 @@ static int tca64_getreg(FAR struct tca64_dev_s *priv, uint8_t regaddr,
     {
       gpioerr("ERROR: I2C addr=%02x regaddr=%02x: failed, ret=%d!\n",
               priv->config->address, regaddr, ret);
+      return ret;
     }
   else
     {
       gpioinfo("I2C addr=%02x regaddr=%02x: read %02x\n",
                priv->config->address, regaddr, *regval);
+      return OK;
     }
-
-  return ret;
 }
 
 /****************************************************************************
@@ -390,14 +390,14 @@ static int tca64_putreg(struct tca64_dev_s *priv, uint8_t regaddr,
     {
       gpioerr("ERROR: claddr=%02x, regaddr=%02x: failed, ret=%d!\n",
               priv->config->address, regaddr, ret);
+      return ret;
     }
   else
     {
       gpioinfo("claddr=%02x, regaddr=%02x, regval=%02x\n",
                priv->config->address, regaddr, regval);
+      return OK;
     }
-
-  return ret;
 }
 
 /****************************************************************************
diff --git a/drivers/sensors/lis2dh.c b/drivers/sensors/lis2dh.c
index 67e0bf1185f..4e06f609cd3 100644
--- a/drivers/sensors/lis2dh.c
+++ b/drivers/sensors/lis2dh.c
@@ -551,12 +551,16 @@ static ssize_t lis2dh_write(FAR struct file *filep, FAR const char *buffer,
 
 static int lis2dh_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
 {
-  FAR struct inode          *inode = filep->f_inode;
-  FAR struct lis2dh_dev_s   *priv  = inode->i_private;
+  FAR struct inode *inode;
+  FAR struct lis2dh_dev_s *priv;
   int ret;
   uint8_t buf;
 
-  DEBUGASSERT(filep != NULL);
+  DEBUGASSERT(filep);
+  inode = filep->f_inode;
+
+  DEBUGASSERT(inode && inode->i_private);
+  priv = (FAR struct lis2dh_dev_s *)inode->i_private;
 
   ret = sem_wait(&priv->devsem);
   if (ret < 0)
@@ -564,17 +568,16 @@ static int lis2dh_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
       return -EINTR;
     }
 
-  ret = OK;
   switch (cmd)
   {
   case SNIOC_WRITESETUP:
     {
-      /* Write to the configuration registers. Arg: uint8_t value */
+      /* Write to the configuration registers. */
 
       ret = lis2dh_setup(priv, (struct lis2dh_setup *)arg);
-      lis2dh_dbg("lis2dh: conf: %02x ret: %d\n", *(uint8_t*)arg, ret);
+      lis2dh_dbg("lis2dh: conf: %p ret: %d\n", (struct lis2dh_setup *)arg, ret);
 
-      /* Make sure interrupt will get cleared (by reading this register) in
+      /* Make sure interrupt will get cleared in
        * case of latched configuration.
        */
 
@@ -1614,7 +1617,7 @@ static int lis2dh_access(FAR struct lis2dh_dev_s *dev, uint8_t subaddr,
       };
 
       retval = I2C_TRANSFER(dev->i2c, msgv, 2);
-      if (retval == OK)
+      if (retval >= 0)
         {
           return length;
         }
diff --git a/drivers/sensors/lis331dl.c b/drivers/sensors/lis331dl.c
index deef62d7051..c8a8cb9500b 100644
--- a/drivers/sensors/lis331dl.c
+++ b/drivers/sensors/lis331dl.c
@@ -125,7 +125,7 @@ struct lis331dl_dev_s
  *           of -length
  *
  * Returned Value:
- *   Returns OK on success or errno is set.
+ *   Returns actual length of data on success or negative value on error.
  *
  ****************************************************************************/
 
@@ -206,7 +206,8 @@ static int lis331dl_access(FAR struct lis331dl_dev_s *dev, uint8_t subaddr,
       }
     };
 
-  if ((retval = I2C_TRANSFER(dev->i2c, msgv, 2)) == OK)
+  retval = I2C_TRANSFER(dev->i2c, msgv, 2);
+  if (retval >= 0)
     {
       return length;
     }
diff --git a/drivers/sensors/lm75.c b/drivers/sensors/lm75.c
index 6fa670e4e6a..025fae0c93b 100644
--- a/drivers/sensors/lm75.c
+++ b/drivers/sensors/lm75.c
@@ -137,6 +137,7 @@ static int lm75_i2c_write(FAR struct lm75_dev_s *priv,
                           FAR const uint8_t *buffer, int buflen)
 {
   struct i2c_msg_s msg;
+  int ret;
 
   /* Setup for the transfer */
 
@@ -148,7 +149,8 @@ static int lm75_i2c_write(FAR struct lm75_dev_s *priv,
 
   /* Then perform the transfer. */
 
-  return I2C_TRANSFER(priv->i2c, &msg, 1);
+  ret = I2C_TRANSFER(priv->i2c, &msg, 1);
+  return (ret >= 0) ? OK : ret;
 }
 
 /****************************************************************************
@@ -163,6 +165,7 @@ static int lm75_i2c_read(FAR struct lm75_dev_s *priv,
                          FAR uint8_t *buffer, int buflen)
 {
   struct i2c_msg_s msg;
+  int ret;
 
   /* Setup for the transfer */
 
@@ -174,7 +177,8 @@ static int lm75_i2c_read(FAR struct lm75_dev_s *priv,
 
   /* Then perform the transfer. */
 
-  return I2C_TRANSFER(priv->i2c, &msg, 1);
+  ret = I2C_TRANSFER(priv->i2c, &msg, 1);
+  return (ret >= 0) ? OK : ret;
 }
 
 /****************************************************************************
diff --git a/drivers/sensors/lm92.c b/drivers/sensors/lm92.c
index 63ea40db38a..47402e35609 100644
--- a/drivers/sensors/lm92.c
+++ b/drivers/sensors/lm92.c
@@ -139,6 +139,7 @@ static int lm92_i2c_write(FAR struct lm92_dev_s *priv,
                           FAR const uint8_t *buffer, int buflen)
 {
   struct i2c_msg_s msg;
+  int ret;
 
   /* Setup for the transfer */
 
@@ -150,7 +151,8 @@ static int lm92_i2c_write(FAR struct lm92_dev_s *priv,
 
   /* Then perform the transfer. */
 
-  return I2C_TRANSFER(priv->i2c, &msg, 1);
+  ret = I2C_TRANSFER(priv->i2c, &msg, 1);
+  return (ret >= 0) ? OK : ret;
 }
 
 /****************************************************************************
@@ -165,6 +167,7 @@ static int lm92_i2c_read(FAR struct lm92_dev_s *priv,
                          FAR uint8_t *buffer, int buflen)
 {
   struct i2c_msg_s msg;
+  int ret;
 
   /* Setup for the transfer */
 
@@ -176,7 +179,8 @@ static int lm92_i2c_read(FAR struct lm92_dev_s *priv,
 
   /* Then perform the transfer. */
 
-  return I2C_TRANSFER(priv->i2c, &msg, 1);
+  ret = I2C_TRANSFER(priv->i2c, &msg, 1);
+  return (ret >= 0) ? OK : ret;
 }
 
 /****************************************************************************
diff --git a/drivers/sensors/ms58xx.c b/drivers/sensors/ms58xx.c
index 3efdda2713b..4e4ff74aee9 100644
--- a/drivers/sensors/ms58xx.c
+++ b/drivers/sensors/ms58xx.c
@@ -253,6 +253,7 @@ static int ms58xx_i2c_write(FAR struct ms58xx_dev_s *priv,
                              FAR const uint8_t *buffer, int buflen)
 {
   struct i2c_msg_s msg;
+  int ret;
 
   /* Setup for the transfer */
 
@@ -264,7 +265,8 @@ static int ms58xx_i2c_write(FAR struct ms58xx_dev_s *priv,
 
   /* Then perform the transfer. */
 
-  return I2C_TRANSFER(priv->i2c, &msg, 1);
+  ret = I2C_TRANSFER(priv->i2c, &msg, 1);
+  return (ret >= 0) ? OK : ret;
 }
 
 /****************************************************************************
@@ -279,6 +281,7 @@ static int ms58xx_i2c_read(FAR struct ms58xx_dev_s *priv,
                             FAR uint8_t *buffer, int buflen)
 {
   struct i2c_msg_s msg;
+  int ret;
 
   /* Setup for the transfer */
 
@@ -290,7 +293,8 @@ static int ms58xx_i2c_read(FAR struct ms58xx_dev_s *priv,
 
   /* Then perform the transfer. */
 
-  return I2C_TRANSFER(priv->i2c, &msg, 1);
+  ret = I2C_TRANSFER(priv->i2c, &msg, 1);
+  return (ret >= 0) ? OK : ret;
 }
 
 /****************************************************************************
diff --git a/drivers/timers/Kconfig b/drivers/timers/Kconfig
index a7f204408d3..48068d41ead 100644
--- a/drivers/timers/Kconfig
+++ b/drivers/timers/Kconfig
@@ -151,7 +151,6 @@ config RTC_DSXXXX
 	bool "DS130x/DS323x RTC Driver"
 	default n
 	select I2C
-	select I2C_TRANSFER
 	select RTC_DATETIME
 	depends on RTC_EXTERNAL
 	---help---
@@ -204,7 +203,6 @@ config RTC_PCF85263
 	bool "PCF85263 RTC Driver"
 	default n
 	select I2C
-	select I2C_TRANSFER
 	select RTC_DATETIME
 	depends on RTC_EXTERNAL
 	---help---
@@ -239,7 +237,6 @@ endif # WATCHDOG
 config TIMERS_CS2100CP
 	bool "CS2100-CP Fraction-N Clock Multiplier"
 	depends on I2C
-	select I2C_TRANSFER
 
 if TIMERS_CS2100CP
 
diff --git a/drivers/timers/cs2100-cp.c b/drivers/timers/cs2100-cp.c
index 82c80bf403b..b73acaa41f5 100644
--- a/drivers/timers/cs2100-cp.c
+++ b/drivers/timers/cs2100-cp.c
@@ -120,6 +120,7 @@ static int cs2100_write_reg(FAR const struct cs2100_config_s *config,
                             uint8_t regaddr, uint8_t regval)
 {
   struct i2c_msg_s msgs[2];
+  int ret;
 
   reginfo("%02x<-%02x\n", regaddr, regval);
   DEBUGASSERT(config->i2c->ops && config->i2c->ops->transfer);
@@ -140,7 +141,8 @@ static int cs2100_write_reg(FAR const struct cs2100_config_s *config,
 
   /* Send the message */
 
-  return I2C_TRANSFER(config->i2c, msgs, 2);
+  ret = I2C_TRANSFER(config->i2c, msgs, 2);
+  return (ret >= 0) ? OK : ret;
 }
 
 /****************************************************************************
@@ -179,7 +181,7 @@ static int cs2100_read_reg(FAR const struct cs2100_config_s *config,
   /* Send the address followed by a STOP */
 
   ret = I2C_TRANSFER(config->i2c, &msg, 1);
-  if (ret == OK)
+  if (ret >= 0)
     {
       msg.frequency = config->i2cfreq;
       msg.addr      = config->i2caddr;
@@ -190,13 +192,13 @@ static int cs2100_read_reg(FAR const struct cs2100_config_s *config,
       /* Read the register beginning with another START */
 
       ret = I2C_TRANSFER(config->i2c, &msg, 1);
-      if (ret == OK)
+      if (ret >= 0)
         {
           reginfo("%02x->%02x\n", regaddr, *regval);
         }
     }
 
-  return ret;
+  return (ret >= 0) ? OK : ret;
 }
 #endif
 
@@ -220,6 +222,7 @@ static int cs2100_write_ratio(FAR const struct cs2100_config_s *config,
 {
   struct i2c_msg_s msg;
   uint8_t buffer[5];
+  int ret;
 
   reginfo("%02x<-%04l\n", CS2100_RATIO0, (unsigned long)ratio);
   DEBUGASSERT(config->i2c->ops && config->i2c->ops->transfer);
@@ -240,7 +243,8 @@ static int cs2100_write_ratio(FAR const struct cs2100_config_s *config,
 
   /* Send the message */
 
-  return I2C_TRANSFER(config->i2c, &msg, 1);
+  ret = I2C_TRANSFER(config->i2c, &msg, 1);
+  return (ret >= 0) ? OK : ret;
 }
 
 /****************************************************************************
@@ -281,7 +285,7 @@ static int cs2100_read_ratio(FAR const struct cs2100_config_s *config,
   /* Send the address followed by a STOP */
 
   ret = I2C_TRANSFER(config->i2c, &msg, 1);
-  if (ret == OK)
+  if (ret >= 0)
     {
       msg.frequency = config->i2cfreq;
       msg.addr      = config->i2caddr;
@@ -295,7 +299,7 @@ static int cs2100_read_ratio(FAR const struct cs2100_config_s *config,
 
       /* Return the ratio */
 
-      if (ret == OK)
+      if (ret >= 0)
         {
            *ratio = ((uint32_t)buffer[0] << 24) |
                     ((uint32_t)buffer[1] << 16) |
@@ -306,7 +310,7 @@ static int cs2100_read_ratio(FAR const struct cs2100_config_s *config,
         }
     }
 
-  return ret;
+  return (ret >= 0) ? OK : ret;
 }
 #endif
 
diff --git a/drivers/usbmisc/fusb301.c b/drivers/usbmisc/fusb301.c
index d57d8a95ecc..c106c0470b5 100644
--- a/drivers/usbmisc/fusb301.c
+++ b/drivers/usbmisc/fusb301.c
@@ -167,7 +167,7 @@ static int fusb301_getreg(FAR struct fusb301_dev_s *priv, uint8_t reg)
   for (retries = 0; retries < FUSB301_I2C_RETRIES; retries++)
     {
       ret = I2C_TRANSFER(priv->i2c, msg, 2);
-      if (ret == OK)
+      if (ret >= 0)
         {
           fusb301_info("reg:%02X, value:%02X\n", reg, regval);
           return regval;