From f0e731ab72d189c9a30983aab95d8b154804bb65 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max@duempel.org>
Date: Tue, 7 May 2013 00:29:22 +0200
Subject: [PATCH] android/GlueIOIOPort: fix spurious errors after IOIO baud
 rate change

Generic solution for the workaround in commit fb7f0ec3.  Fixes TRAC
tickets #2733, #2754.
---
 NEWS.txt                             |  1 +
 android/src/AbstractAndroidPort.java |  2 +-
 android/src/GlueIOIOPort.java        | 37 ++++++++++++++++++++++++++++++++++++
 3 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/NEWS.txt b/NEWS.txt
index 6193cd095..122abb321 100644
--- a/NEWS.txt
+++ b/NEWS.txt
@@ -10,6 +10,7 @@ Version 6.6.1 - not yet released
 * devices
   - indicate duplicate devices in list
   - allow using more than one TCP/UDP device
+  - fix spurious errors after IOIO baud rate change (#2733, #2754)
 * configuration
   - fix regression with polar configuration (#2803)
 
diff --git a/android/src/AbstractAndroidPort.java b/android/src/AbstractAndroidPort.java
index a8cd2adda..44370ba10 100644
--- a/android/src/AbstractAndroidPort.java
+++ b/android/src/AbstractAndroidPort.java
@@ -94,7 +94,7 @@ abstract class AbstractAndroidPort implements AndroidPort {
     return o != null && o.drain();
   }
 
-  @Override public final int write(byte[] data, int length) {
+  @Override public int write(byte[] data, int length) {
     OutputThread o = output;
     return o != null
       ? o.write(data, length)
diff --git a/android/src/GlueIOIOPort.java b/android/src/GlueIOIOPort.java
index 64eb9f04d..35c981ca7 100644
--- a/android/src/GlueIOIOPort.java
+++ b/android/src/GlueIOIOPort.java
@@ -40,6 +40,13 @@ final class GlueIOIOPort extends IOIOPort implements IOIOConnectionListener {
 
   private IOIOConnectionHolder holder;
   private boolean connected;
+
+  /**
+   * Set to true when the connection is being cycled, e.g. during a
+   * baud rate change.  It is used by waitCycled().
+   */
+  private boolean cycling;
+
   private final int inPin;
   private final int outPin;
   private int baudrate = 0;
@@ -70,6 +77,24 @@ final class GlueIOIOPort extends IOIOPort implements IOIOConnectionListener {
     _holder.addListener(this);
   }
 
+  /**
+   * Wait for a certain amoutn of time until the port has been
+   * reconnected after a baud rate change.  Call this to avoid
+   * spurious I/O errors while the baud rate is being changed.
+   */
+  private synchronized void waitCycled() {
+    if (!cycling)
+      return;
+
+    /* wait only once */
+    cycling = false;
+
+    try {
+      wait(200);
+    } catch (InterruptedException e) {
+    }
+  }
+
   @Override public void onIOIOConnect(IOIO ioio)
     throws ConnectionLostException, InterruptedException {
     connected = true;
@@ -84,6 +109,11 @@ final class GlueIOIOPort extends IOIOPort implements IOIOConnectionListener {
     }
 
     set(uart);
+
+    synchronized(this) {
+      cycling = false;
+      notifyAll();
+    }
   }
 
   @Override public void onIOIODisconnect() {
@@ -123,7 +153,14 @@ final class GlueIOIOPort extends IOIOPort implements IOIOConnectionListener {
       return false;
 
     baudrate = _baudrate;
+    if (connected)
+      cycling = true;
     holder.cycleListener(this);
     return true;
   }
+
+  @Override public int write(byte[] data, int length) {
+    waitCycled();
+    return super.write(data, length);
+  }
 }
-- 
2.11.4.GIT