Add an analog joystick driver. Initial checkin is only a little more of a clone of the discrete joystick driver and is as-of-yet untested

drivers/input/Kconfig

@@ -340,3 +340,21 @@ config DJOYSTICK_NPOLLWAITERS
 	depends on !DISABLE_POLL
 
 endif # DJOYSTICK
+
+config AJOYSTICK
+	bool "Analog Joystick"
+	default n
+	---help---
+		Enable standard analog joystick upper half driver.  An analog
+		joystick refers to a joystick that provides position data as an
+		integer value that might have been obtained through DACs.
+		Discrete button inputs are also supported.
+
+if AJOYSTICK
+
+config AJOYSTICK_NPOLLWAITERS
+	int "Max Number of Poll Waiters"
+	default 2
+	depends on !DISABLE_POLL
+
+endif # AJOYSTICK

drivers/input/Make.defs

@@ -75,6 +75,10 @@ ifeq ($(CONFIG_DJOYSTICK),y)
   CSRCS += djoystick.c
 endif
 
+ifeq ($(CONFIG_AJOYSTICK),y)
+  CSRCS += ajoystick.c
+endif
+
 # Include input device driver build support
 
 DEPPATH += --dep-path input

drivers/input/djoystick.c

@@ -340,7 +340,7 @@ static void djoy_sample(FAR struct djoy_upperhalf_s *priv)
                   fds->revents |= (fds->events & POLLIN);
                   if (fds->revents != 0)
                     {
-                      ivdbg("Report events: %02x\n", fds->revents);
+                      illvdbg("Report events: %02x\n", fds->revents);
                       sem_post(fds->sem);
                     }
                 }
@@ -550,6 +550,16 @@ static ssize_t djoy_read(FAR struct file *filep, FAR char *buffer,
   DEBUGASSERT(inode->i_private);
   priv  = (FAR struct djoy_upperhalf_s *)inode->i_private;
 
+  /* Make sure that the buffer is sufficiently large to hold at least one
+   * complete sample.
+   */
+
+  if (len < sizeof(djoy_buttonset_t))
+    {
+      ivdbg("ERROR: buffer too small: %lu\n", (unsigned long)len);
+      return -EINVAL;
+    }
+
   /* Get exclusive access to the driver structure */
 
   ret = djoy_takesem(&priv->du_exclsem);
@@ -568,7 +578,7 @@ static ssize_t djoy_read(FAR struct file *filep, FAR char *buffer,
   ret = sizeof(djoy_buttonset_t);
 
   djoy_givesem(&priv->du_exclsem);
-  return ret;
+  return (ssize_t)ret;
 }
 
 /****************************************************************************