diff --git a/drivers/mtd/m25px.c b/drivers/mtd/m25px.c
index c7b5c495ea..3b509eb6c5 100644
--- a/drivers/mtd/m25px.c
+++ b/drivers/mtd/m25px.c
@@ -432,7 +432,6 @@ static void m25p_waitwritecomplete(struct m25p_dev_s *priv)
     {
       /* Select this FLASH part */
 
-      m25p_lock(priv->dev);
       SPI_SELECT(priv->dev, SPIDEV_FLASH(0), true);
 
       /* Send "Read Status Register (RDSR)" command */
@@ -446,7 +445,6 @@ static void m25p_waitwritecomplete(struct m25p_dev_s *priv)
       /* Deselect the FLASH */
 
       SPI_SELECT(priv->dev, SPIDEV_FLASH(0), false);
-      m25p_unlock(priv->dev);
 
       /* Given that writing could take up to few tens of milliseconds, and erasing
        * could take more.  The following short delay in the "busy" case will allow
@@ -455,7 +453,9 @@ static void m25p_waitwritecomplete(struct m25p_dev_s *priv)
 
       if ((status & M25P_SR_WIP) != 0)
         {
+          m25p_unlock(priv->dev);
           usleep(1000);
+          m25p_lock(priv->dev);
         }
     }
   while ((status & M25P_SR_WIP) != 0);
@@ -471,7 +471,6 @@ static void m25p_writeenable(struct m25p_dev_s *priv)
 {
   /* Select this FLASH part */
 
-  m25p_lock(priv->dev);
   SPI_SELECT(priv->dev, SPIDEV_FLASH(0), true);
 
   /* Send "Write Enable (WREN)" command */
@@ -481,8 +480,6 @@ static void m25p_writeenable(struct m25p_dev_s *priv)
   /* Deselect the FLASH */
 
   SPI_SELECT(priv->dev, SPIDEV_FLASH(0), false);
-  m25p_unlock(priv->dev);
-
   finfo("Enabled\n");
 }
 
@@ -521,7 +518,6 @@ static void m25p_sectorerase(struct m25p_dev_s *priv, off_t sector, uint8_t type
 
   /* Select this FLASH part */
 
-  m25p_lock(priv->dev);
   SPI_SELECT(priv->dev, SPIDEV_FLASH(0), true);
 
   /* Send the "Sector Erase (SE)" or Sub-Sector Erase (SSE) instruction
@@ -542,8 +538,6 @@ static void m25p_sectorerase(struct m25p_dev_s *priv, off_t sector, uint8_t type
   /* Deselect the FLASH */
 
   SPI_SELECT(priv->dev, SPIDEV_FLASH(0), false);
-  m25p_unlock(priv->dev);
-
   finfo("Erased\n");
 }
 
@@ -569,7 +563,6 @@ static inline int m25p_bulkerase(struct m25p_dev_s *priv)
 
   /* Select this FLASH part */
 
-  m25p_lock(priv->dev);
   SPI_SELECT(priv->dev, SPIDEV_FLASH(0), true);
 
   /* Send the "Bulk Erase (BE)" instruction */
@@ -579,8 +572,6 @@ static inline int m25p_bulkerase(struct m25p_dev_s *priv)
   /* Deselect the FLASH */
 
   SPI_SELECT(priv->dev, SPIDEV_FLASH(0), false);
-  m25p_unlock(priv->dev);
-
   finfo("Return: OK\n");
   return OK;
 }
@@ -610,7 +601,6 @@ static inline void m25p_pagewrite(struct m25p_dev_s *priv, FAR const uint8_t *bu
 
   /* Select this FLASH part */
 
-  m25p_lock(priv->dev);
   SPI_SELECT(priv->dev, SPIDEV_FLASH(0), true);
 
   /* Send "Page Program (PP)" command */
@@ -630,8 +620,6 @@ static inline void m25p_pagewrite(struct m25p_dev_s *priv, FAR const uint8_t *bu
   /* Deselect the FLASH: Chip Select high */
 
   SPI_SELECT(priv->dev, SPIDEV_FLASH(0), false);
-  m25p_unlock(priv->dev);
-
   finfo("Written\n");
 }
 
@@ -659,7 +647,6 @@ static inline void m25p_bytewrite(struct m25p_dev_s *priv, FAR const uint8_t *bu
 
   /* Select this FLASH part */
 
-  m25p_lock(priv->dev);
   SPI_SELECT(priv->dev, SPIDEV_FLASH(0), true);
 
   /* Send "Page Program (PP)" command */
@@ -679,8 +666,6 @@ static inline void m25p_bytewrite(struct m25p_dev_s *priv, FAR const uint8_t *bu
   /* Deselect the FLASH: Chip Select high */
 
   SPI_SELECT(priv->dev, SPIDEV_FLASH(0), false);
-  m25p_unlock(priv->dev);
-
   finfo("Written\n");
 }
 #endif
@@ -698,6 +683,7 @@ static int m25p_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblock
 
   /* Lock access to the SPI bus until we complete the erase */
 
+  m25p_lock(priv->dev);
   while (blocksleft > 0)
     {
 #ifdef CONFIG_M25P_SUBSECTOR_ERASE
@@ -747,6 +733,7 @@ static int m25p_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblock
       blocksleft--;
     }
 
+  m25p_unlock(priv->dev);
   return (int)nblocks;
 }
 
@@ -788,6 +775,7 @@ static ssize_t m25p_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, size_t n
 
   /* Lock the SPI bus and write each page to FLASH */
 
+  m25p_lock(priv->dev);
   while (blocksleft-- > 0)
     {
       m25p_pagewrite(priv, buffer, startblock);
@@ -795,6 +783,7 @@ static ssize_t m25p_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, size_t n
       startblock++;
    }
 
+  m25p_unlock(priv->dev);
   return nblocks;
 }
 
@@ -840,7 +829,6 @@ static ssize_t m25p_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes,
 
   SPI_SELECT(priv->dev, SPIDEV_FLASH(0), false);
   m25p_unlock(priv->dev);
-
   finfo("return nbytes: %d\n", (int)nbytes);
   return nbytes;
 }
@@ -973,7 +961,9 @@ static int m25p_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg)
         {
             /* Erase the entire device */
 
+            m25p_lock(priv->dev);
             ret = m25p_bulkerase(priv);
+            m25p_unlock(priv->dev);
         }
         break;