diff --git a/arch/arm/src/sama5/sam_ohci.c b/arch/arm/src/sama5/sam_ohci.c
index 2c2fe658220..a8a10ebfaa3 100644
--- a/arch/arm/src/sama5/sam_ohci.c
+++ b/arch/arm/src/sama5/sam_ohci.c
@@ -215,8 +215,6 @@ struct sam_rhport_s
 
 struct sam_ohci_s
 {
-  /* Driver status */
-
   volatile bool rhswait;       /* TRUE: Thread is waiting for Root Hub Status change */
 
 #ifndef CONFIG_USBHOST_INT_DISABLE
@@ -611,7 +609,7 @@ static void sam_putle16(uint8_t *dest, uint16_t val)
  * Name: sam_edalloc
  *
  * Description:
- *   Return an endpoint descriptor to the free list
+ *   Allocate an endpoint descriptor by removing it from the free list
  *
  *******************************************************************************/
 
@@ -634,7 +632,7 @@ static struct sam_ed_s *sam_edalloc(void)
  * Name: sam_edfree
  *
  * Description:
- *   Return an endpoint descriptor to the free list
+ *   Free an endpoint descriptor by returning to the free list
  *
  *******************************************************************************/
 
@@ -686,7 +684,7 @@ static struct sam_gtd_s *sam_tdalloc(void)
  * Name: sam_tdfree
  *
  * Description:
- *   Return an transfer descriptor to the free list
+ *   Free a transfer descriptor by returning it to the free list
  *
  * Assumptions:
  *   - Only called from the WDH interrupt handler (and during initialization).
diff --git a/include/nuttx/kmalloc.h b/include/nuttx/kmalloc.h
index 69ceb06bf13..495fccc142b 100644
--- a/include/nuttx/kmalloc.h
+++ b/include/nuttx/kmalloc.h
@@ -97,6 +97,7 @@ extern "C"
 # define kumalloc(s)             malloc(s)
 # define kuzalloc(s)             zalloc(s)
 # define kurealloc(p,s)          realloc(p,s)
+# define kumemalign(a,s)         memalign(a,s)
 # define kufree(p)               free(p)
 
 #else
@@ -108,6 +109,7 @@ extern "C"
 # define kumalloc(s)             umm_malloc(s)
 # define kuzalloc(s)             umm_zalloc(s)
 # define kurealloc(p,s)          umm_realloc(p,s)
+# define kumemalign(a,s)         umm_memalign(a,s)
 # define kufree(p)               umm_free(p)
 
 #endif
@@ -127,6 +129,7 @@ extern "C"
 # define kmalloc(s)             malloc(s)
 # define kzalloc(s)             zalloc(s)
 # define krealloc(p,s)          realloc(p,s)
+# define kmemalign(a,s)         memalign(a,s)
 # define kfree(p)               free(p)
 
 #elif !defined(CONFIG_MM_KERNEL_HEAP)
@@ -143,6 +146,7 @@ extern "C"
 # define kmalloc(s)             umm_malloc(s)
 # define kzalloc(s)             umm_zalloc(s)
 # define krealloc(p,s)          umm_realloc(p,s)
+# define kmemalign(a,s)         umm_memalign(a,s)
 # define kfree(p)               umm_free(p)
 
 #else
@@ -158,6 +162,7 @@ void kmm_givesemaphore(void);
 FAR void *kmalloc(size_t size);
 FAR void *kzalloc(size_t size);
 FAR void *krealloc(FAR void *oldmem, size_t newsize);
+FAR void *kmemalign(size_t alignment, size_t size);
 void kfree(FAR void *mem);
 
 #ifdef CONFIG_DEBUG
diff --git a/include/nuttx/usb/ehci.h b/include/nuttx/usb/ehci.h
index 01dd69751b1..ee65339e037 100755
--- a/include/nuttx/usb/ehci.h
+++ b/include/nuttx/usb/ehci.h
@@ -536,7 +536,7 @@
 #define QTD_TOKEN_IOC                  (1 << 15)  /* Bit 15: Interrupt On Complete */
 #define QTD_TOKEN_NBYTES_SHIFT         (16)       /* Bits 16-30: Total Bytes to Transfer */
 #define QTD_TOKEN_NBYTES_MASK          (0x7fff << QTD_TOKEN_NBYTES_SHIFT)
-#define QTD_TOKEN_TOGGLE               (1 << 13)  /* Bit 31: Data Toggle
+#define QTD_TOKEN_TOGGLE               (1 << 13)  /* Bit 31: Data Toggle */
 
 /* qTD Buffer Page Pointer List. Paragraph 3.5.4 */
 /* Page 0 */
diff --git a/include/nuttx/userspace.h b/include/nuttx/userspace.h
index 6a78c6ffa12..5115aad7d34 100644
--- a/include/nuttx/userspace.h
+++ b/include/nuttx/userspace.h
@@ -91,6 +91,7 @@
 #  define umm_malloc(s)       USERSPACE->mm_malloc(s)
 #  define umm_zalloc(s)       USERSPACE->mm_zalloc(s)
 #  define umm_realloc(p,s)    USERSPACE->mm_realloc(p,s)
+#  define umm_memalign(a,s)   USERSPACE->mm_memalign(a,s)
 #  define umm_free(p)         USERSPACE->mm_free(p)
 #endif
 
@@ -140,6 +141,9 @@ struct userspace_s
 
   FAR void *(*mm_malloc)(size_t size);
   FAR void *(*mm_realloc)(FAR void *oldmem, size_t newsize);
+#if 0 /* Not yet integrated */
+  FAR void *(*mm_memalign)(size_t alignment, size_t size);
+#endif
   FAR void *(*mm_zalloc)(size_t size);
   void (*mm_free)(FAR void *mem);
 
diff --git a/mm/mm_kernel.c b/mm/mm_kernel.c
index 0cf592e0a8f..ee156e88903 100644
--- a/mm/mm_kernel.c
+++ b/mm/mm_kernel.c
@@ -168,6 +168,26 @@ FAR void *krealloc(FAR void *oldmem, size_t newsize)
   return mm_realloc(&g_kmmheap, oldmem, newsize);
 }
 
+/************************************************************************
+ * Name: kmemalign
+ *
+ * Description:
+ *   Allocate aligned memory in the kernel heap.
+ *
+ * Parameters:
+ *   alignment - Log2 byte alignment
+ *   size - Size (in bytes) of the new memory region to be allocated.
+ *
+ * Return Value:
+ *   The address of the re-allocated memory (NULL on failure to allocate)
+ *
+ ************************************************************************/
+
+FAR void *kmemalign(size_t alignment, size_t size)
+{
+  return mm_memalign(&g_kmmheap, alignment, size);
+}
+
 /************************************************************************
  * Name: kfree
  *