HID: Refactored shared memory decoding for touchpad support.

src/core/hle/service/hid/hid.cpp

@@ -25,17 +25,17 @@ Kernel::SharedPtr<Kernel::Event> g_event_debug_pad;
 
 // Next Pad state update information
 static PadState next_state = {{0}};
-static u32 next_index = 0;
-static s16 next_circle_x = 0;
-static s16 next_circle_y = 0;
+static u32 next_pad_index = 0;
+static s16 next_pad_circle_x = 0;
+static s16 next_pad_circle_y = 0;
 
 /**
  * Gets a pointer to the PadData structure inside HID shared memory
  */
-static inline PadData* GetPadData() {
+static inline SharedMem* GetPadData() {
     if (g_shared_mem == nullptr)
         return nullptr;
-    return reinterpret_cast<PadData*>(g_shared_mem->GetPointer().ValueOr(nullptr));
+    return reinterpret_cast<SharedMem*>(g_shared_mem->GetPointer().ValueOr(nullptr));
 }
 
 // TODO(peachum):
@@ -60,10 +60,10 @@ static inline PadData* GetPadData() {
  */
 static void UpdateNextCirclePadState() {
     static const s16 max_value = 0x9C;
-    next_circle_x = next_state.circle_left ? -max_value : 0x0;
-    next_circle_x += next_state.circle_right ? max_value : 0x0;
-    next_circle_y = next_state.circle_down ? -max_value : 0x0;
-    next_circle_y += next_state.circle_up ? max_value : 0x0;
+    next_pad_circle_x = next_state.circle_left ? -max_value : 0x0;
+    next_pad_circle_x += next_state.circle_right ? max_value : 0x0;
+    next_pad_circle_y = next_state.circle_down ? -max_value : 0x0;
+    next_pad_circle_y += next_state.circle_up ? max_value : 0x0;
 }
 
 /**
@@ -87,20 +87,18 @@ void PadButtonRelease(const PadState& pad_state) {
  * including both Pad key changes and analog circle Pad changes.
  */
 void PadUpdateComplete() {
-    PadData* pad_data = GetPadData();
+    SharedMem* shared_mem = GetPadData();
 
-    if (pad_data == nullptr) {
+    if (shared_mem == nullptr)
         return;
-    }
 
-    // Update PadData struct
-    pad_data->current_state.hex = next_state.hex;
-    pad_data->index = next_index;
-    next_index = (next_index + 1) % pad_data->entries.size();
+    shared_mem->pad.current_state.hex = next_state.hex;
+    shared_mem->pad.index = next_pad_index;
+    next_pad_index = (next_pad_index + 1) % shared_mem->pad.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;
+    u32 last_entry_index = (shared_mem->pad.index - 1) % shared_mem->pad.entries.size();
+    PadState old_state = shared_mem->pad.entries[last_entry_index].current_state;
 
     // Compute bitmask with 1s for bits different from the old state
     PadState changed;
@@ -115,7 +113,7 @@ void PadUpdateComplete() {
     removals.hex = changed.hex & old_state.hex;
 
     // Get the current Pad entry
-    PadDataEntry* current_pad_entry = &pad_data->entries[pad_data->index];
+    PadDataEntry* current_pad_entry = &shared_mem->pad.entries[shared_mem->pad.index];
 
     // Update entry properties
     current_pad_entry->current_state.hex = next_state.hex;
@@ -123,8 +121,19 @@ void PadUpdateComplete() {
     current_pad_entry->delta_removals.hex = removals.hex;
 
     // Set circle Pad
-    current_pad_entry->circle_pad_x = next_circle_x;
-    current_pad_entry->circle_pad_y = next_circle_y;
+    current_pad_entry->circle_pad_x = next_pad_circle_x;
+    current_pad_entry->circle_pad_y = next_pad_circle_y;
+
+    // If we just updated index 0, provide a new timestamp
+    if (shared_mem->pad.index == 0) {
+        shared_mem->pad.index_reset_ticks_previous = shared_mem->pad.index_reset_ticks;
+        shared_mem->pad.index_reset_ticks = (s64)Core::g_app_core->GetTicks();
+    }
+
+    // Signal both handles when there's an update to Pad or touch
+    g_event_pad_or_touch_1->Signal();
+    g_event_pad_or_touch_2->Signal();
+}
 
     // If we just updated index 0, provide a new timestamp
     if (pad_data->index == 0) {

src/core/hle/service/hid/hid.h

@@ -65,7 +65,7 @@ struct PadState {
 };
 
 /**
- * Structure of a single entry in the PadData's Pad state history array.
+ * Structure of a single entry of Pad state history within HID shared memory
  */
 struct PadDataEntry {
     PadState current_state;
@@ -77,22 +77,44 @@ struct PadDataEntry {
 };
 
 /**
- * Structure of all data related to the 3DS Pad.
+ * Structure of a single entry of touch state history within HID shared memory
  */
-struct PadData {
-    s64 index_reset_ticks;
-    s64 index_reset_ticks_previous;
-    u32 index; // the index of the last updated Pad state history element
+struct TouchDataEntry {
+    u16 x;
+    u16 y;
+    u32 data_valid;
+};
+
+/**
+ * Structure of data stored in HID shared memory
+ */
+struct SharedMem {
+    // Offset 0x0 : "PAD" data, this is used for buttons and the circle pad
+    struct {
+        s64 index_reset_ticks;
+        s64 index_reset_ticks_previous;
+        u32 index; // Index of the last updated pad state history element
+
+        INSERT_PADDING_BYTES(0x8);
+
+        PadState current_state; // Same as entries[index].current_state
+        u32 raw_circle_pad_data;
+
+        INSERT_PADDING_BYTES(0x4);
 
-    u32 pad1;
-    u32 pad2;
+        std::array<PadDataEntry, 8> entries; // Pad state history
+    } pad;
 
-    PadState current_state; // same as entries[index].current_state
-    u32 raw_circle_pad_data;
+    // Offset 0xA8 : Touchpad data, this is used for touchpad input
+    struct {
+        s64 index_reset_ticks;
+        s64 index_reset_ticks_previous;
+        u32 index; // Index of the last updated touch state history element
 
-    u32 pad3;
+        INSERT_PADDING_BYTES(0xC);
 
-    std::array<PadDataEntry, 8> entries; // Pad state history
+        std::array<TouchDataEntry, 8> entries;
+    } touch;
 };
 
 // Pre-defined PadStates for single button presses