2 files changed, 197 insertions, 24 deletions

diff --git a/src/core/hle/service/hid.cpp b/src/core/hle/service/hid.cpp
index 6a4895c90..1ef39fced 100644
--- a/src/core/hle/service/hid.cpp
+++ b/src/core/hle/service/hid.cpp
@@ -16,6 +16,121 @@ namespace HID_User {
 
 Handle g_shared_mem = 0; ///< Handle to shared memory region designated to HID_User service
 
+// Event handles
+Handle g_event_pad_or_touch_1 = 0;
+Handle g_event_pad_or_touch_2 = 0;
+Handle g_event_accelerometer = 0;
+Handle g_event_gyroscope = 0;
+Handle g_event_debug_pad = 0;
+
+// Next PAD state update information
+PADState g_next_state = {{0}};
+u32 g_next_index = 0;
+s16 g_next_circle_x = 0;
+s16 g_next_circle_y = 0;
+
+/** Gets a pointer to the PADData structure inside HID shared memory
+ */
+static inline PADData* GetPADData() {
+    if (0 == g_shared_mem)
+        return nullptr;
+
+    return reinterpret_cast<PADData*>(Kernel::GetSharedMemoryPointer(g_shared_mem, 0));
+}
+
+/** Circle PAD from keys.
+ *
+ *  This is implemented as "pushed all the way to an edge (max) or centered (0)".
+ *
+ *  Indicate the circle pad is pushed completely to the edge in 1 of 8 directions.
+ */
+void UpdateNextCirclePADState() {
+    static const s16 max_value = 0x9C;
+    g_next_circle_x = g_next_state.circle_left ? -max_value : 0x0;
+    g_next_circle_x += g_next_state.circle_right ? max_value : 0x0;
+    g_next_circle_y = g_next_state.circle_down ? -max_value : 0x0;
+    g_next_circle_y += g_next_state.circle_up ? max_value : 0x0;
+}
+
+/** Sets a PAD state (button or button combo) as pressed
+ */
+void PADButtonPress(PADState pad_state) {
+    g_next_state.hex |= pad_state.hex;
+    UpdateNextCirclePADState();
+}
+
+/** Sets a PAD state (button or button combo) as released
+ */
+void PADButtonRelease(PADState pad_state) {
+    g_next_state.hex &= ~pad_state.hex;
+    UpdateNextCirclePADState();
+}
+
+/** Called after all PAD changes to be included in this update have been made,
+ *  including both PAD key changes and analog circle PAD changes.
+ */
+void PADUpdateComplete() {
+    PADData* pad_data = GetPADData();
+
+    // Update PADData struct
+    pad_data->current_state.hex = g_next_state.hex;
+    pad_data->index = g_next_index;
+    g_next_index = (g_next_index + 1) % pad_data->entries.size();
+
+    // Get the previous PAD state
+    u32 last_entry_index = (pad_data->index - 1) % pad_data->entries.size();
+    PADState old_state = pad_data->entries[last_entry_index].current_state;
+
+    // Compute bitmask with 1s for bits different from the old state
+    PADState changed;
+    changed.hex = (g_next_state.hex ^ old_state.hex);
+
+    // Compute what was added
+    PADState additions;
+    additions.hex = changed.hex & g_next_state.hex;
+
+    // Compute what was removed
+    PADState removals;
+    removals.hex = changed.hex & old_state.hex;
+
+    // Get the current PAD entry
+    PADDataEntry* current_pad_entry = &pad_data->entries[pad_data->index];
+
+    // Update entry properties
+    current_pad_entry->current_state.hex = g_next_state.hex;
+    current_pad_entry->delta_additions.hex = additions.hex;
+    current_pad_entry->delta_removals.hex = removals.hex;
+
+    // Set circle PAD
+    current_pad_entry->circle_pad_x = g_next_circle_x;
+    current_pad_entry->circle_pad_y = g_next_circle_y;
+
+    // If we just updated index 0, provide a new timestamp
+    if (pad_data->index == 0) {
+        pad_data->index_reset_ticks_previous = pad_data->index_reset_ticks;
+        pad_data->index_reset_ticks = (s64)Core::g_app_core->GetTicks();
+    }
+
+    // Signal both handles when there's an update to PAD or touch
+    Kernel::SignalEvent(g_event_pad_or_touch_1);
+    Kernel::SignalEvent(g_event_pad_or_touch_2);
+}
+
+
+// TODO(peachum):
+// Add a method for setting analog input from joystick device for the circle PAD.
+//
+// This method should:
+//     * Be called after both PADButton<Press, Release>().
+//     * Be called before PADUpdateComplete()
+//     * Set current PADEntry.circle_pad_<axis> using analog data
+//     * Set PadData.raw_circle_pad_data
+//     * Set PadData.current_state.circle_right = 1 if current PADEntry.circle_pad_x >= 41
+//     * Set PadData.current_state.circle_up = 1 if current PADEntry.circle_pad_y >= 41
+//     * Set PadData.current_state.circle_left = 1 if current PADEntry.circle_pad_x <= -41
+//     * Set PadData.current_state.circle_right = 1 if current PADEntry.circle_pad_y <= -41
+
+
 /**
  * HID_User::GetIPCHandles service function
  *  Inputs:
@@ -35,11 +150,11 @@ void GetIPCHandles(Service::Interface* self) {
 
     cmd_buff[1] = 0; // No error
     cmd_buff[3] = g_shared_mem;
-    cmd_buff[4] = Kernel::CreateEvent(RESETTYPE_ONESHOT, "HID_User:EventA");
-    cmd_buff[5] = Kernel::CreateEvent(RESETTYPE_ONESHOT, "HID_User:EventB");
-    cmd_buff[6] = Kernel::CreateEvent(RESETTYPE_ONESHOT, "HID_User:EventC");
-    cmd_buff[7] = Kernel::CreateEvent(RESETTYPE_ONESHOT, "HID_User:EventGyroscope");
-    cmd_buff[8] = Kernel::CreateEvent(RESETTYPE_ONESHOT, "HID_User:EventD");
+    cmd_buff[4] = g_event_pad_or_touch_1;
+    cmd_buff[5] = g_event_pad_or_touch_2;
+    cmd_buff[6] = g_event_accelerometer;
+    cmd_buff[7] = g_event_gyroscope;
+    cmd_buff[8] = g_event_debug_pad;
 
     DEBUG_LOG(KERNEL, "called");
 }
@@ -58,14 +173,19 @@ const Interface::FunctionInfo FunctionTable[] = {
 };
 
 
-
-
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 // Interface class
 
 Interface::Interface() {
     g_shared_mem = Kernel::CreateSharedMemory("HID_User:SharedMem"); // Create shared memory object
 
+    // Create event handles
+    g_event_pad_or_touch_1 = Kernel::CreateEvent(RESETTYPE_ONESHOT, "HID_User:EventPADOrTouch1");
+    g_event_pad_or_touch_2 = Kernel::CreateEvent(RESETTYPE_ONESHOT, "HID_User:EventPADOrTouch2");
+    g_event_accelerometer = Kernel::CreateEvent(RESETTYPE_ONESHOT, "HID_User:EventAccelerometer");
+    g_event_gyroscope = Kernel::CreateEvent(RESETTYPE_ONESHOT, "HID_User:EventGyroscope");
+    g_event_debug_pad = Kernel::CreateEvent(RESETTYPE_ONESHOT, "HID_User:EventDebugPAD");
+
     Register(FunctionTable, ARRAY_SIZE(FunctionTable));
 }
 
diff --git a/src/core/hle/service/hid.h b/src/core/hle/service/hid.h
index 6ddf2f80f..f5f76f0fc 100644
--- a/src/core/hle/service/hid.h
+++ b/src/core/hle/service/hid.h
@@ -15,30 +15,83 @@
 
 namespace HID_User {
 
+/// Structure of a PAD controller state
 struct PADState {
     union {
         u32 hex;
 
-        BitField<0, 1, u32> A;
-        BitField<1, 1, u32> B;
-        BitField<2, 1, u32> Select;
-        BitField<3, 1, u32> Start;
-        BitField<4, 1, u32> Right;
-        BitField<5, 1, u32> Left;
-        BitField<6, 1, u32> Up;
-        BitField<7, 1, u32> Down;
-        BitField<8, 1, u32> R;
-        BitField<9, 1, u32> L;
-        BitField<10, 1, u32> X;
-        BitField<11, 1, u32> Y;
-
-        BitField<28, 1, u32> CircleRight;
-        BitField<29, 1, u32> CircleLeft;
-        BitField<30, 1, u32> CircleUp;
-        BitField<31, 1, u32> CircleDown;
+        BitField<0, 1, u32> a;
+        BitField<1, 1, u32> b;
+        BitField<2, 1, u32> select;
+        BitField<3, 1, u32> start;
+        BitField<4, 1, u32> right;
+        BitField<5, 1, u32> left;
+        BitField<6, 1, u32> up;
+        BitField<7, 1, u32> down;
+        BitField<8, 1, u32> r;
+        BitField<9, 1, u32> l;
+        BitField<10, 1, u32> x;
+        BitField<11, 1, u32> y;
+
+        BitField<28, 1, u32> circle_right;
+        BitField<29, 1, u32> circle_left;
+        BitField<30, 1, u32> circle_up;
+        BitField<31, 1, u32> circle_down;
     };
 };
 
+/// Structure of a single entry in the PADData's PAD state history array
+struct PADDataEntry {
+    PADState current_state;
+    PADState delta_additions;
+    PADState delta_removals;
+
+    s16 circle_pad_x;
+    s16 circle_pad_y;
+};
+
+/// Structure of all data related to the 3DS Pad
+struct PADData {
+    s64 index_reset_ticks;
+    s64 index_reset_ticks_previous;
+    u32 index; // the index of the last updated PAD state history element
+
+    u32 pad1;
+    u32 pad2;
+
+    PADState current_state; // same as entries[index].current_state
+    u32 raw_circle_pad_data;
+
+    u32 pad3;
+
+    std::array<PADDataEntry, 8> entries; // PAD state history
+};
+
+// Pre-defined PADStates for single button presses
+const PADState PAD_NONE         = {{0}};
+const PADState PAD_A            = {{1u << 0}};
+const PADState PAD_B            = {{1u << 1}};
+const PADState PAD_SELECT       = {{1u << 2}};
+const PADState PAD_START        = {{1u << 3}};
+const PADState PAD_RIGHT        = {{1u << 4}};
+const PADState PAD_LEFT         = {{1u << 5}};
+const PADState PAD_UP           = {{1u << 6}};
+const PADState PAD_DOWN         = {{1u << 7}};
+const PADState PAD_R            = {{1u << 8}};
+const PADState PAD_L            = {{1u << 9}};
+const PADState PAD_X            = {{1u << 10}};
+const PADState PAD_Y            = {{1u << 11}};
+const PADState PAD_CIRCLE_RIGHT = {{1u << 28}};
+const PADState PAD_CIRCLE_LEFT  = {{1u << 29}};
+const PADState PAD_CIRCLE_UP    = {{1u << 30}};
+const PADState PAD_CIRCLE_DOWN  = {{1u << 31}};
+
+// Methods for updating the HID module's state
+void PADButtonPress(PADState pad_state);
+void PADButtonRelease(PADState pad_state);
+void PADUpdateComplete();
+
+/// HID service interface
 class Interface : public Service::Interface {
 public: