Improved thresholding logic in the STMPE11 driver; NxWM: Oops minimizing wrong application

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4737 42af7a65-404d-4744-a932-0658087f49c3

ChangeLog

@@ -2760,3 +2760,10 @@
 	  window to revert to the previous window.  Not good behavior.
 	* sched/sched_mergepending.c:  Add task switching instrumentation.  There is a case
 	  here where instrumentation was missing.  Contributed by Petri Tanskanen.
+	CONFIG_STMPE11_THRESHX, CONFIG_STMPE11_THRESHX, and drivers/stmpe11_tsc.c:  Add some
+	  threasholding controls to all slow down processing of touchscreen samples.
+	  This is a problem with NX in multi-user mode:  touchscreen data gets sent
+	  via a message and when the message queue gets full the sender blocks and
+	  touch events are lost.  Basic data overrun.  The badly effects touchscreen
+	  human factors.
+  

Documentation/NuttxPortingGuide.html

@@ -4730,6 +4730,15 @@ build
     <code>CONFIG_STMPE11_REGDEBUG</code>:
       Enabled very low register-level debug output.  Requires <code>CONFIG_DEBUG</code>.
   </li>
+  <li>
+    <code>CONFIG_STMPE11_THRESHX</code> and <code>CONFIG_STMPE11_THRESHY</code>:
+    STMPE11 touchscreen data comes in a a very high rate.  New touch positions
+    will only be reported when the X or Y data changes by these thresholds.
+    This trades reduces data rate for some loss in dragging accuracy.  The
+    STMPE11 is configure for 12-bit values so the raw ranges are 0-4095. So
+    for example, if your display is 320x240, then THRESHX=13 and THRESHY=17
+    would correspond to one pixel.  Default: 12
+  </li>
 </ul>
 
 <h3>Analog Devices</h3>

configs/README.txt

@@ -814,6 +814,13 @@ defconfig -- This is a configuration file similar to the Linux
       Disable driver temperature sensor functionality.
     CONFIG_STMPE11_REGDEBUG
       Enabled very low register-level debug output.  Requires CONFIG_DEBUG.
+    CONFIG_STMPE11_THRESHX and CONFIG_STMPE11_THRESHY
+      STMPE11 touchscreen data comes in a a very high rate.  New touch positions
+      will only be reported when the X or Y data changes by these thresholds.
+      This trades reduces data rate for some loss in dragging accuracy.  The
+      STMPE11 is configure for 12-bit values so the raw ranges are 0-4095. So
+      for example, if your display is 320x240, then THRESHX=13 and THRESHY=17
+      would correspond to one pixel.  Default: 12
 
   Analog Devices
 

configs/stm3240g-eval/nsh/defconfig

@@ -990,6 +990,13 @@ CONFIG_INPUT_TSC2007=n
 #   Disable driver temperature sensor functionality.
 # CONFIG_STMPE11_REGDBUG
 #   Enabled very low register-level debug output.  Requires CONFIG_DEBUG.
+# CONFIG_STMPE11_THRESHX and CONFIG_STMPE11_THRESHY
+#   STMPE11 touchscreen data comes in a a very high rate.  New touch positions
+#   will only be reported when the X or Y data changes by these thresholds.
+#   This trades reduces data rate for some loss in dragging accuracy.  The
+#   STMPE11 is configure for 12-bit values so the raw ranges are 0-4095. So
+#   for example, if your display is 320x240, then THRESHX=13 and THRESHY=17
+#   would correspond to one pixel.  Default: 12
 #
 CONFIG_INPUT_STMPE11=n
 CONFIG_STMPE11_SPI=n
@@ -1005,7 +1012,8 @@ CONFIG_STMPE11_GPIOINT_DISABLE=y
 CONFIG_STMPE11_SWAPXY=y
 CONFIG_STMPE11_TEMP_DISABLE=y
 CONFIG_STMPE11_REGDEBUG=n
-
+CONFIG_STMPE11_THRESHX=26
+CONFIG_STMPE11_THRESHY=34
 #
 # USB Device Configuration
 #

configs/stm3240g-eval/nxwm/defconfig

@@ -990,6 +990,13 @@ CONFIG_INPUT_TSC2007=n
 #   Disable driver temperature sensor functionality.
 # CONFIG_STMPE11_REGDBUG
 #   Enabled very low register-level debug output.  Requires CONFIG_DEBUG.
+# CONFIG_STMPE11_THRESHX and CONFIG_STMPE11_THRESHY
+#   STMPE11 touchscreen data comes in a a very high rate.  New touch positions
+#   will only be reported when the X or Y data changes by these thresholds.
+#   This trades reduces data rate for some loss in dragging accuracy.  The
+#   STMPE11 is configure for 12-bit values so the raw ranges are 0-4095. So
+#   for example, if your display is 320x240, then THRESHX=13 and THRESHY=17
+#   would correspond to one pixel.  Default: 12
 #
 CONFIG_INPUT_STMPE11=n
 CONFIG_STMPE11_SPI=n
@@ -1005,6 +1012,8 @@ CONFIG_STMPE11_GPIOINT_DISABLE=y
 CONFIG_STMPE11_SWAPXY=n
 CONFIG_STMPE11_TEMP_DISABLE=y
 CONFIG_STMPE11_REGDEBUG=n
+CONFIG_STMPE11_THRESHX=26
+CONFIG_STMPE11_THRESHY=34
 
 #
 # USB Device Configuration

drivers/input/stmpe11_tsc.c

@@ -986,19 +986,17 @@ void stmpe11_tscworker(FAR struct stmpe11_dev_s *priv, uint8_t intsta)
           goto ignored;
         }
 
-      /* Perform a thresholding operation so that the results will be more stable */
+      /* Perform a thresholding operation so that the results will be more stable.
+       * If the difference from the last sample is small, then ignore the event.
+       * REVISIT:  Should a large change in pressure also generate a event?
+       */
 
       xdiff = x > priv->threshx ? (x - priv->threshx) : (priv->threshx - x);
       ydiff = y > priv->threshy ? (y - priv->threshy) : (priv->threshy - y);
 
-      /* If the difference from the last sample is small, then ignore the event.
-       * REVISIT:  Should a large change in pressure also generate a event?
-       */
-
-      if (xdiff + ydiff < 6)
+      if (xdiff < CONFIG_STMPE11_THRESHX && ydiff < CONFIG_STMPE11_THRESHY)
         {
-          /* Little or no change in position ... don't report anything.
-           */
+          /* Little or no change in either direction ... don't report anything. */
 
           goto ignored;
         }

include/nuttx/input/stmpe11.h

@@ -86,6 +86,13 @@
  *   Disable driver temperature sensor functionality.
  * CONFIG_STMPE11_REGDEBUG
  *   Enabled very low register-level debug output.  Requires CONFIG_DEBUG.
+ * CONFIG_STMPE11_THRESHX and CONFIG_STMPE11_THRESHY
+ *   STMPE11 touchscreen data comes in a a very high rate.  New touch positions
+ *   will only be reported when the X or Y data changes by these thresholds.
+ *   This trades reduces data rate for some loss in dragging accuracy.  The
+ *   STMPE11 is configure for 12-bit values so the raw ranges are 0-4095. So
+ *   for example, if your display is 320x240, then THRESHX=13 and THRESHY=17
+ *   would correspond to one pixel.  Default: 12
  */
 
 /* The STMPE811 interfaces with the target CPU via a I2C or SPI interface. The pin IN_1
@@ -127,6 +134,16 @@
 #  error "Work queue support required.  CONFIG_SCHED_WORKQUEUE must be selected."
 #endif
 
+/* Thresholds */
+
+#ifndef CONFIG_STMPE11_THRESHX
+#  define CONFIG_STMPE11_THRESHX 12
+#endif
+
+#ifndef CONFIG_STMPE11_THRESHY
+#  define CONFIG_STMPE11_THRESHY 12
+#endif
+
 /* Debug output */
 
 #ifndef CONFIG_DEBUG