diff --git a/drivers/input/djoystick.c b/drivers/input/djoystick.c
index 05342c29a7..2be11ec54b 100644
--- a/drivers/input/djoystick.c
+++ b/drivers/input/djoystick.c
@@ -584,6 +584,7 @@ static int djoy_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
   FAR struct inode *inode;
   FAR struct djoy_upperhalf_s *priv;
   FAR struct djoy_open_s *opriv;
+  FAR const struct djoy_lowerhalf_s *lower;
   int ret;
 
   DEBUGASSERT(filep && filep->f_priv && filep->f_inode);
@@ -606,6 +607,29 @@ static int djoy_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
   ret = -EINVAL;
   switch (cmd)
     {
+    /* Command:     DJOYIOC_SUPPORTED
+     * Description: Report the set of button events supported by the hardware;
+     * Argument:    A pointer to writeable integer value in which to return the
+     *              set of supported buttons.
+     * Return:      Zero (OK) on success.  Minus one will be returned on failure
+     *              with the errno value set appropriately.
+     */
+
+    case DJOYIOC_SUPPORTED:
+      {
+        FAR int *supported = (FAR int *)((uintptr_t)arg);
+
+        if (supported)
+          {
+            lower = priv->du_lower;
+            DEBUGASSERT(lower && lower->dl_supported);
+
+            *supported = (int)lower->dl_supported(lower);
+            ret = OK;
+          }
+      }
+      break;
+
 #ifndef CONFIG_DISABLE_POLL
     /* Command:     DJOYIOC_POLLEVENTS
      * Description: Specify the set of button events that can cause a poll()
diff --git a/include/nuttx/input/djoystick.h b/include/nuttx/input/djoystick.h
index 32f30eaeb9..14ef508ceb 100644
--- a/include/nuttx/input/djoystick.h
+++ b/include/nuttx/input/djoystick.h
@@ -80,6 +80,7 @@
 #define DJOY_BUTTON_2        (5)                  /* Bit 5: Button 2 */
 #define DJOY_BUTTON_3        (6)                  /* Bit 6: Button 3 */
 #define DJOY_BUTTON_4        (7)                  /* Bit 7: Button 4 */
+#define DJOY_NDISCRETES      (8)                  /* Total number of discrete signals */
 
 #define DJOY_UP_BIT          (1 << DJOY_UP)       /* 1:Joystick UP selected */
 #define DJOY_DOWN_BIT        (1 << DJOY_DOWN)     /* 1:Joystick DOWN selected */
@@ -112,12 +113,27 @@
  *
  * 1) The read() method will always return a single value of size
  *    djoy_buttonset_t represent the current state of the joystick buttons.
+ *    read() never blocks.
  * 2) The poll() method can be used to notify a client if there is a change
  *    in any of the joystick discrete inputs.  This feature, of course,
- *    depends upon interrupt GPIO support from the platform.
+ *    depends upon interrupt GPIO support from the platform.  NOTE: that
+ *    semantics of poll() for POLLIN are atypical:  The successful poll
+ *    means that the data has changed and has nothing to with the
+ *    availability of data to be read; data is always available to be
+ *    read.
  * 3) The ioctl() method supports the commands documented below:
  */
 
+/* Command:     DJOYIOC_SUPPORTED
+ * Description: Report the set of button events supported by the hardware;
+ * Argument:    A pointer to writeable integer value in which to return the
+ *              set of supported buttons.
+ * Return:      Zero (OK) on success.  Minus one will be returned on failure
+ *              with the errno value set appropriately.
+ */
+
+#define DJOYIOC_SUPPORTED  _DJOYIOC(0x0001)
+
 /* Command:     DJOYIOC_POLLEVENTS
  * Description: Specify the set of button events that can cause a poll()
  *              to awaken.  The default is all button depressions and all
@@ -127,7 +143,7 @@
  *              with the errno value set appropriately.
  */
 
-#define DJOYIOC_POLLEVENTS  _DJOYIOC(0x0001)
+#define DJOYIOC_POLLEVENTS  _DJOYIOC(0x0002)
 
 /* Command:     DJOYIOC_REGISTER
  * Description: Register to receive a signal whenever there is a change in
@@ -139,7 +155,7 @@
  *              with the errno value set appropriately.
  */
 
-#define DJOYIOC_REGISTER   _DJOYIOC(0x0002)
+#define DJOYIOC_REGISTER   _DJOYIOC(0x0003)
 
 /****************************************************************************
  * Public Types