LinuxInputDevice: add support for multi-touch devices

Adds support for multi-touch devices on Linux.
Support is limited to devices that are capable of
tracking identifiable contacts, and use the type B events of:

https://www.kernel.org/doc/Documentation/input/multi-touch-protocol.txt

Signed-off-by: Floris Bos <bos@je-eigen-domein.nl>

6 files changed, 125 insertions, 1 deletions

diff --git a/Makefile.in b/Makefile.in
index e7276bfe1e..8ead761782 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -158,6 +158,8 @@ DIRECTORY_ARCHIVES += xbmc/storage/android/storage_android.a
 DIRECTORY_ARCHIVES += xbmc/windowing/X11/windowing_X11.a
 else
 DIRECTORY_ARCHIVES += xbmc/input/linux/input_linux.a
+DIRECTORY_ARCHIVES += xbmc/input/touch/input_touch.a
+DIRECTORY_ARCHIVES += xbmc/input/touch/generic/input_touch_generic.a
 DIRECTORY_ARCHIVES += xbmc/network/linux/network_linux.a
 DIRECTORY_ARCHIVES += xbmc/powermanagement/linux/powermanagement_linux.a
 DIRECTORY_ARCHIVES += xbmc/storage/linux/storage_linux.a
diff --git a/xbmc/input/linux/LinuxInputDevices.cpp b/xbmc/input/linux/LinuxInputDevices.cpp
index 0b9a2c736b..723f7ae80a 100644
--- a/xbmc/input/linux/LinuxInputDevices.cpp
+++ b/xbmc/input/linux/LinuxInputDevices.cpp
@@ -96,6 +96,8 @@ typedef unsigned long kernel_ulong_t;
 #include "LinuxInputDevices.h"
 #include "input/MouseStat.h"
 #include "utils/log.h"
+#include "input/touch/generic/GenericTouchActionHandler.h"
+#include "input/touch/generic/GenericTouchInputHandler.h"
 
 #ifndef BITS_PER_LONG
 #define BITS_PER_LONG        (sizeof(long) * 8)
@@ -268,7 +270,8 @@ typedef enum
   LI_DEVICE_MOUSE    = 1,
   LI_DEVICE_JOYSTICK = 2,
   LI_DEVICE_KEYBOARD = 4,
-  LI_DEVICE_REMOTE   = 8
+  LI_DEVICE_REMOTE   = 8,
+  LI_DEVICE_MULTITOUCH = 16
 } LinuxInputDeviceType;
 
 typedef enum
@@ -302,6 +305,10 @@ CLinuxInputDevice::CLinuxInputDevice(const std::string& fileName, int index):
   m_deviceMaxKeyCode = 0;
   m_deviceMaxAxis = 0;
   m_bUnplugged = false;
+  m_mt_currentSlot = 0;
+  memset(&m_mt_x, 0, sizeof(m_mt_x));
+  memset(&m_mt_y, 0, sizeof(m_mt_y));
+  memset(&m_mt_event, 0, sizeof(m_mt_event));
 
   Open();
 }
@@ -664,11 +671,102 @@ bool CLinuxInputDevice::AbsEvent(const struct input_event& levt, XBMC_Event& dev
 }
 
 /*
+ * Process multi-touch absolute events
+ * Only store the information, do not fire event until we receive an EV_SYN
+ */
+bool CLinuxInputDevice::mtAbsEvent(const struct input_event& levt)
+{
+  switch (levt.code)
+  {
+  case ABS_MT_SLOT:
+    m_mt_currentSlot = levt.value;
+    break;
+
+  case ABS_MT_TRACKING_ID:
+    if (m_mt_currentSlot < TOUCH_MAX_POINTERS)
+    {
+      if (levt.value == -1)
+        m_mt_event[m_mt_currentSlot] = TouchInputUp;
+      else
+        m_mt_event[m_mt_currentSlot] = TouchInputDown;
+    }
+    break;
+
+  case ABS_MT_POSITION_X:
+    if (m_mt_currentSlot < TOUCH_MAX_POINTERS)
+    {
+      m_mt_x[m_mt_currentSlot] = levt.value;
+      if (m_mt_event[m_mt_currentSlot] == TouchInputUnchanged)
+        m_mt_event[m_mt_currentSlot] = TouchInputMove;
+    }
+    break;
+
+  case ABS_MT_POSITION_Y:
+    if (m_mt_currentSlot < TOUCH_MAX_POINTERS)
+    {
+      m_mt_y[m_mt_currentSlot] = levt.value;
+      if (m_mt_event[m_mt_currentSlot] == TouchInputUnchanged)
+        m_mt_event[m_mt_currentSlot] = TouchInputMove;
+    }
+    break;
+
+  default:
+    return false;
+  }
+
+  return true;
+}
+
+/*
+ * Process stored multi-touch events
+ */
+bool CLinuxInputDevice::mtSynEvent(const struct input_event& levt)
+{
+  float size = 10.0f;
+  int64_t nanotime = levt.time.tv_sec * 1000000000LL + levt.time.tv_usec * 1000LL;
+
+  for (int ptr=0; ptr < TOUCH_MAX_POINTERS; ptr++)
+  {
+    /* While the comments of ITouchInputHandler::UpdateTouchPointer() say
+       "If there's an event for every touch action this method does not need to be called at all"
+       gesture detection currently doesn't work properly without this call. */
+    CGenericTouchInputHandler::GetInstance().UpdateTouchPointer(ptr, m_mt_x[ptr], m_mt_y[ptr], nanotime, size);
+  }
+
+  for (int ptr=0; ptr < TOUCH_MAX_POINTERS; ptr++)
+  {
+    if (m_mt_event[ptr] != TouchInputUnchanged)
+    {
+      CGenericTouchInputHandler::GetInstance().HandleTouchInput(m_mt_event[ptr], m_mt_x[ptr], m_mt_y[ptr], nanotime, ptr, size);
+      m_mt_event[ptr] = TouchInputUnchanged;
+    }
+  }
+
+  return true;
+}
+
+/*
  * Translates a Linux input event into a DirectFB input event.
  */
 bool CLinuxInputDevice::TranslateEvent(const struct input_event& levt,
     XBMC_Event& devt)
 {
+  if (m_devicePreferredId == LI_DEVICE_MULTITOUCH)
+  {
+    switch (levt.type)
+    {
+    case EV_ABS:
+      return mtAbsEvent(levt);
+
+    case EV_SYN:
+      return mtSynEvent(levt);
+
+    default:
+      // Ignore legacy (key) events
+      return false;
+    }
+  }
+
   switch (levt.type)
   {
   case EV_KEY:
@@ -913,6 +1011,10 @@ void CLinuxInputDevice::GetInfo(int fd)
     for (i = 0; i < ABS_PRESSURE; i++)
       if (test_bit( i, absbit ))
         num_abs++;
+
+    /* test if it is a multi-touch type B device */
+    if (test_bit(ABS_MT_SLOT, absbit))
+      m_deviceType |= LI_DEVICE_MULTITOUCH;
   }
 
   /* Mouse, Touchscreen or Smartpad ? */
@@ -958,6 +1060,11 @@ void CLinuxInputDevice::GetInfo(int fd)
   /* Decide which primary input device to be. */
   if (m_deviceType & LI_DEVICE_KEYBOARD)
     m_devicePreferredId = LI_DEVICE_KEYBOARD;
+  else if (m_deviceType & LI_DEVICE_MULTITOUCH)
+  {
+    m_devicePreferredId = LI_DEVICE_MULTITOUCH;
+    CGenericTouchInputHandler::GetInstance().RegisterHandler(&CGenericTouchActionHandler::GetInstance());
+  }
   else if (m_deviceType & LI_DEVICE_REMOTE)
     m_devicePreferredId = LI_DEVICE_REMOTE;
   else if (m_deviceType & LI_DEVICE_JOYSTICK)
diff --git a/xbmc/input/linux/LinuxInputDevices.h b/xbmc/input/linux/LinuxInputDevices.h
index 954d823540..8c88a1df5f 100644
--- a/xbmc/input/linux/LinuxInputDevices.h
+++ b/xbmc/input/linux/LinuxInputDevices.h
@@ -26,6 +26,8 @@
 #include "windowing/XBMC_events.h"
 #include "input/XBMC_keyboard.h"
 #include "threads/SingleLock.h"
+#include "input/touch/ITouchInputHandler.h"
+#include "input/touch/generic/IGenericTouchGestureDetector.h"
 
 struct KeymapEntry
 {
@@ -60,6 +62,8 @@ private:
   XBMCMod UpdateModifiers(XBMC_Event& devt);
   bool GetKeymapEntry(KeymapEntry& entry);
   int KeyboardGetSymbol(unsigned short value);
+  bool mtAbsEvent(const struct input_event& levt);
+  bool mtSynEvent(const struct input_event& levt);
 
   int m_fd;
   int m_vt_fd;
@@ -81,6 +85,10 @@ private:
   bool m_bSkipNonKeyEvents;
   bool m_bUnplugged;
   std::deque<XBMC_Event> m_equeue;
+  int m_mt_currentSlot;
+  int m_mt_x[TOUCH_MAX_POINTERS];
+  int m_mt_y[TOUCH_MAX_POINTERS];
+  TouchInput m_mt_event[TOUCH_MAX_POINTERS];
 };
 
 class CLinuxInputDevices
diff --git a/xbmc/input/touch/ITouchInputHandler.h b/xbmc/input/touch/ITouchInputHandler.h
index 6ea47dbc8d..43c7a76cdf 100644
--- a/xbmc/input/touch/ITouchInputHandler.h
+++ b/xbmc/input/touch/ITouchInputHandler.h
@@ -28,6 +28,7 @@
  * \brief Touch input event
  */
 typedef enum {
+  TouchInputUnchanged = 0,
   TouchInputAbort,
   TouchInputDown,
   TouchInputUp,
diff --git a/xbmc/windowing/WinEventsLinux.cpp b/xbmc/windowing/WinEventsLinux.cpp
index 6f97e9e4f7..aaba119d54 100644
--- a/xbmc/windowing/WinEventsLinux.cpp
+++ b/xbmc/windowing/WinEventsLinux.cpp
@@ -79,4 +79,9 @@ size_t CWinEventsLinux::GetQueueSize()
   return m_devices.Size();
 }
 
+void CWinEventsLinux::MessagePush(XBMC_Event *ev)
+{
+  g_application.OnEvent(*ev);
+}
+
 #endif
diff --git a/xbmc/windowing/WinEventsLinux.h b/xbmc/windowing/WinEventsLinux.h
index f6c8df05b1..a17e9878e2 100644
--- a/xbmc/windowing/WinEventsLinux.h
+++ b/xbmc/windowing/WinEventsLinux.h
@@ -31,6 +31,7 @@ public:
   CWinEventsLinux();
   bool MessagePump();
   size_t GetQueueSize();
+  void MessagePush(XBMC_Event *ev);
   void RefreshDevices();
   void Notify(const Observable &obs, const ObservableMessage msg)
   {