3 files changed, 158 insertions, 28 deletions

diff --git a/quantum/split_common/matrix.c b/quantum/split_common/matrix.c
index 51bf8b109..d6636b886 100644
--- a/quantum/split_common/matrix.c
+++ b/quantum/split_common/matrix.c
@@ -114,9 +114,9 @@ static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row)
     // Start with a clear matrix row
     matrix_row_t current_row_value = 0;
 
-    // Select row and wait for row selecton to stabilize
+    // Select row
     select_row(current_row);
-    matrix_io_delay();
+    matrix_output_select_delay();
 
     // For each col...
     for (uint8_t col_index = 0; col_index < MATRIX_COLS; col_index++) {
@@ -129,6 +129,9 @@ static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row)
 
     // Unselect row
     unselect_row(current_row);
+    if (current_row + 1 < MATRIX_ROWS) {
+        matrix_output_unselect_delay();  // wait for row signal to go HIGH
+    }
 
     // If the row has changed, store the row and return the changed flag.
     if (current_matrix[current_row] != current_row_value) {
@@ -160,9 +163,9 @@ static void init_pins(void) {
 static bool read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col) {
     bool matrix_changed = false;
 
-    // Select col and wait for col selecton to stabilize
+    // Select col
     select_col(current_col);
-    matrix_io_delay();
+    matrix_output_select_delay();
 
     // For each row...
     for (uint8_t row_index = 0; row_index < ROWS_PER_HAND; row_index++) {
@@ -188,6 +191,9 @@ static bool read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col)
 
     // Unselect col
     unselect_col(current_col);
+    if (current_col + 1 < MATRIX_COLS) {
+        matrix_output_unselect_delay();  // wait for col signal to go HIGH
+    }
 
     return matrix_changed;
 }
@@ -245,48 +251,62 @@ void matrix_init(void) {
     split_post_init();
 }
 
-void matrix_post_scan(void) {
+bool matrix_post_scan(void) {
+    bool changed = false;
     if (is_keyboard_master()) {
         static uint8_t error_count;
 
-        if (!transport_master(matrix + thatHand)) {
+        matrix_row_t slave_matrix[ROWS_PER_HAND] = {0};
+        if (!transport_master(matrix + thisHand, slave_matrix)) {
             error_count++;
 
             if (error_count > ERROR_DISCONNECT_COUNT) {
                 // reset other half if disconnected
                 for (int i = 0; i < ROWS_PER_HAND; ++i) {
                     matrix[thatHand + i] = 0;
+                    slave_matrix[i]      = 0;
                 }
+
+                changed = true;
             }
         } else {
             error_count = 0;
+
+            for (int i = 0; i < ROWS_PER_HAND; ++i) {
+                if (matrix[thatHand + i] != slave_matrix[i]) {
+                    matrix[thatHand + i] = slave_matrix[i];
+                    changed              = true;
+                }
+            }
         }
 
         matrix_scan_quantum();
     } else {
-        transport_slave(matrix + thisHand);
+        transport_slave(matrix + thatHand, matrix + thisHand);
 
         matrix_slave_scan_user();
     }
+
+    return changed;
 }
 
 uint8_t matrix_scan(void) {
-    bool changed = false;
+    bool local_changed = false;
 
 #if defined(DIRECT_PINS) || (DIODE_DIRECTION == COL2ROW)
     // Set row, read cols
     for (uint8_t current_row = 0; current_row < ROWS_PER_HAND; current_row++) {
-        changed |= read_cols_on_row(raw_matrix, current_row);
+        local_changed |= read_cols_on_row(raw_matrix, current_row);
     }
 #elif (DIODE_DIRECTION == ROW2COL)
     // Set col, read rows
     for (uint8_t current_col = 0; current_col < MATRIX_COLS; current_col++) {
-        changed |= read_rows_on_col(raw_matrix, current_col);
+        local_changed |= read_rows_on_col(raw_matrix, current_col);
     }
 #endif
 
-    debounce(raw_matrix, matrix + thisHand, ROWS_PER_HAND, changed);
+    debounce(raw_matrix, matrix + thisHand, ROWS_PER_HAND, local_changed);
 
-    matrix_post_scan();
-    return (uint8_t)changed;
+    bool remote_changed = matrix_post_scan();
+    return (uint8_t)(local_changed || remote_changed);
 }
diff --git a/quantum/split_common/transport.c b/quantum/split_common/transport.c
index 467ff81a9..61b61ea08 100644
--- a/quantum/split_common/transport.c
+++ b/quantum/split_common/transport.c
@@ -6,6 +6,7 @@
 #include "quantum.h"
 
 #define ROWS_PER_HAND (MATRIX_ROWS / 2)
+#define SYNC_TIMER_OFFSET 2
 
 #ifdef RGBLIGHT_ENABLE
 #    include "rgblight.h"
@@ -27,8 +28,23 @@ static pin_t encoders_pad[] = ENCODERS_PAD_A;
 #    include "i2c_slave.h"
 
 typedef struct _I2C_slave_buffer_t {
+#    ifndef DISABLE_SYNC_TIMER
+    uint32_t sync_timer;
+#    endif
+#    ifdef SPLIT_TRANSPORT_MIRROR
+    matrix_row_t mmatrix[ROWS_PER_HAND];
+#    endif
     matrix_row_t smatrix[ROWS_PER_HAND];
-    uint8_t      backlight_level;
+#    ifdef SPLIT_MODS_ENABLE
+    uint8_t real_mods;
+    uint8_t weak_mods;
+#        ifndef NO_ACTION_ONESHOT
+    uint8_t oneshot_mods;
+#        endif
+#    endif
+#    ifdef BACKLIGHT_ENABLE
+    uint8_t backlight_level;
+#    endif
 #    if defined(RGBLIGHT_ENABLE) && defined(RGBLIGHT_SPLIT)
     rgblight_syncinfo_t rgblight_sync;
 #    endif
@@ -42,9 +58,14 @@ typedef struct _I2C_slave_buffer_t {
 
 static I2C_slave_buffer_t *const i2c_buffer = (I2C_slave_buffer_t *)i2c_slave_reg;
 
+#    define I2C_SYNC_TIME_START offsetof(I2C_slave_buffer_t, sync_timer)
+#    define I2C_KEYMAP_MASTER_START offsetof(I2C_slave_buffer_t, mmatrix)
+#    define I2C_KEYMAP_SLAVE_START offsetof(I2C_slave_buffer_t, smatrix)
+#    define I2C_REAL_MODS_START offsetof(I2C_slave_buffer_t, real_mods)
+#    define I2C_WEAK_MODS_START offsetof(I2C_slave_buffer_t, weak_mods)
+#    define I2C_ONESHOT_MODS_START offsetof(I2C_slave_buffer_t, oneshot_mods)
 #    define I2C_BACKLIGHT_START offsetof(I2C_slave_buffer_t, backlight_level)
 #    define I2C_RGB_START offsetof(I2C_slave_buffer_t, rgblight_sync)
-#    define I2C_KEYMAP_START offsetof(I2C_slave_buffer_t, smatrix)
 #    define I2C_ENCODER_START offsetof(I2C_slave_buffer_t, encoder_state)
 #    define I2C_WPM_START offsetof(I2C_slave_buffer_t, current_wpm)
 
@@ -55,8 +76,11 @@ static I2C_slave_buffer_t *const i2c_buffer = (I2C_slave_buffer_t *)i2c_slave_re
 #    endif
 
 // Get rows from other half over i2c
-bool transport_master(matrix_row_t matrix[]) {
-    i2c_readReg(SLAVE_I2C_ADDRESS, I2C_KEYMAP_START, (void *)matrix, sizeof(i2c_buffer->smatrix), TIMEOUT);
+bool transport_master(matrix_row_t master_matrix[], matrix_row_t slave_matrix[]) {
+    i2c_readReg(SLAVE_I2C_ADDRESS, I2C_KEYMAP_SLAVE_START, (void *)slave_matrix, sizeof(i2c_buffer->smatrix), TIMEOUT);
+#    ifdef SPLIT_TRANSPORT_MIRROR
+    i2c_writeReg(SLAVE_I2C_ADDRESS, I2C_KEYMAP_MASTER_START, (void *)master_matrix, sizeof(i2c_buffer->mmatrix), TIMEOUT);
+#    endif
 
     // write backlight info
 #    ifdef BACKLIGHT_ENABLE
@@ -91,12 +115,48 @@ bool transport_master(matrix_row_t matrix[]) {
         }
     }
 #    endif
+
+#    ifdef SPLIT_MODS_ENABLE
+    uint8_t real_mods = get_mods();
+    if (real_mods != i2c_buffer->real_mods) {
+        if (i2c_writeReg(SLAVE_I2C_ADDRESS, I2C_REAL_MODS_START, (void *)&real_mods, sizeof(real_mods), TIMEOUT) >= 0) {
+            i2c_buffer->real_mods = real_mods;
+        }
+    }
+
+    uint8_t weak_mods = get_weak_mods();
+    if (weak_mods != i2c_buffer->weak_mods) {
+        if (i2c_writeReg(SLAVE_I2C_ADDRESS, I2C_WEAK_MODS_START, (void *)&weak_mods, sizeof(weak_mods), TIMEOUT) >= 0) {
+            i2c_buffer->weak_mods = weak_mods;
+        }
+    }
+
+#        ifndef NO_ACTION_ONESHOT
+    uint8_t oneshot_mods = get_oneshot_mods();
+    if (oneshot_mods != i2c_buffer->oneshot_mods) {
+        if (i2c_writeReg(SLAVE_I2C_ADDRESS, I2C_ONESHOT_MODS_START, (void *)&oneshot_mods, sizeof(oneshot_mods), TIMEOUT) >= 0) {
+            i2c_buffer->oneshot_mods = oneshot_mods;
+        }
+    }
+#        endif
+#    endif
+
+#    ifndef DISABLE_SYNC_TIMER
+    i2c_buffer->sync_timer = sync_timer_read32() + SYNC_TIMER_OFFSET;
+    i2c_writeReg(SLAVE_I2C_ADDRESS, I2C_SYNC_TIME_START, (void *)&i2c_buffer->sync_timer, sizeof(i2c_buffer->sync_timer), TIMEOUT);
+#    endif
     return true;
 }
 
-void transport_slave(matrix_row_t matrix[]) {
+void transport_slave(matrix_row_t master_matrix[], matrix_row_t slave_matrix[]) {
+#    ifndef DISABLE_SYNC_TIMER
+    sync_timer_update(i2c_buffer->sync_timer);
+#    endif
     // Copy matrix to I2C buffer
-    memcpy((void *)i2c_buffer->smatrix, (void *)matrix, sizeof(i2c_buffer->smatrix));
+    memcpy((void *)i2c_buffer->smatrix, (void *)slave_matrix, sizeof(i2c_buffer->smatrix));
+#    ifdef SPLIT_TRANSPORT_MIRROR
+    memcpy((void *)master_matrix, (void *)i2c_buffer->mmatrix, sizeof(i2c_buffer->mmatrix));
+#    endif
 
 // Read Backlight Info
 #    ifdef BACKLIGHT_ENABLE
@@ -118,6 +178,14 @@ void transport_slave(matrix_row_t matrix[]) {
 #    ifdef WPM_ENABLE
     set_current_wpm(i2c_buffer->current_wpm);
 #    endif
+
+#    ifdef SPLIT_MODS_ENABLE
+    set_mods(i2c_buffer->real_mods);
+    set_weak_mods(i2c_buffer->weak_mods);
+#        ifndef NO_ACTION_ONESHOT
+    set_oneshot_mods(i2c_buffer->oneshot_mods);
+#        endif
+#    endif
 }
 
 void transport_master_init(void) { i2c_init(); }
@@ -139,11 +207,24 @@ typedef struct _Serial_s2m_buffer_t {
 } Serial_s2m_buffer_t;
 
 typedef struct _Serial_m2s_buffer_t {
+#    ifdef SPLIT_MODS_ENABLE
+    uint8_t      real_mods;
+    uint8_t      weak_mods;
+#        ifndef NO_ACTION_ONESHOT
+    uint8_t      oneshot_mods;
+#        endif
+#    endif
+#    ifndef DISABLE_SYNC_TIMER
+    uint32_t     sync_timer;
+#    endif
+#    ifdef SPLIT_TRANSPORT_MIRROR
+    matrix_row_t mmatrix[ROWS_PER_HAND];
+#    endif
 #    ifdef BACKLIGHT_ENABLE
-    uint8_t backlight_level;
+    uint8_t      backlight_level;
 #    endif
 #    ifdef WPM_ENABLE
-    uint8_t current_wpm;
+    uint8_t      current_wpm;
 #    endif
 } Serial_m2s_buffer_t;
 
@@ -221,7 +302,7 @@ void transport_rgblight_slave(void) {
 #        define transport_rgblight_slave()
 #    endif
 
-bool transport_master(matrix_row_t matrix[]) {
+bool transport_master(matrix_row_t master_matrix[], matrix_row_t slave_matrix[]) {
 #    ifndef SERIAL_USE_MULTI_TRANSACTION
     if (soft_serial_transaction() != TRANSACTION_END) {
         return false;
@@ -235,7 +316,10 @@ bool transport_master(matrix_row_t matrix[]) {
 
     // TODO:  if MATRIX_COLS > 8 change to unpack()
     for (int i = 0; i < ROWS_PER_HAND; ++i) {
-        matrix[i] = serial_s2m_buffer.smatrix[i];
+        slave_matrix[i]              = serial_s2m_buffer.smatrix[i];
+#    ifdef SPLIT_TRANSPORT_MIRROR
+        serial_m2s_buffer.mmatrix[i] = master_matrix[i];
+#    endif
     }
 
 #    ifdef BACKLIGHT_ENABLE
@@ -249,16 +333,34 @@ bool transport_master(matrix_row_t matrix[]) {
 
 #    ifdef WPM_ENABLE
     // Write wpm to slave
-    serial_m2s_buffer.current_wpm = get_current_wpm();
+    serial_m2s_buffer.current_wpm  = get_current_wpm();
+#    endif
+
+#    ifdef SPLIT_MODS_ENABLE
+    serial_m2s_buffer.real_mods    = get_mods();
+    serial_m2s_buffer.weak_mods    = get_weak_mods();
+#        ifndef NO_ACTION_ONESHOT
+    serial_m2s_buffer.oneshot_mods = get_oneshot_mods();
+#        endif
+#    endif
+#    ifndef DISABLE_SYNC_TIMER
+    serial_m2s_buffer.sync_timer   = sync_timer_read32() + SYNC_TIMER_OFFSET;
 #    endif
     return true;
 }
 
-void transport_slave(matrix_row_t matrix[]) {
+void transport_slave(matrix_row_t master_matrix[], matrix_row_t slave_matrix[]) {
     transport_rgblight_slave();
+#    ifndef DISABLE_SYNC_TIMER
+    sync_timer_update(serial_m2s_buffer.sync_timer);
+#    endif
+
     // TODO: if MATRIX_COLS > 8 change to pack()
     for (int i = 0; i < ROWS_PER_HAND; ++i) {
-        serial_s2m_buffer.smatrix[i] = matrix[i];
+        serial_s2m_buffer.smatrix[i] = slave_matrix[i];
+#    ifdef SPLIT_TRANSPORT_MIRROR
+        master_matrix[i]             = serial_m2s_buffer.mmatrix[i];
+#    endif
     }
 #    ifdef BACKLIGHT_ENABLE
     backlight_set(serial_m2s_buffer.backlight_level);
@@ -271,6 +373,14 @@ void transport_slave(matrix_row_t matrix[]) {
 #    ifdef WPM_ENABLE
     set_current_wpm(serial_m2s_buffer.current_wpm);
 #    endif
+
+#    ifdef SPLIT_MODS_ENABLE
+    set_mods(serial_m2s_buffer.real_mods);
+    set_weak_mods(serial_m2s_buffer.weak_mods);
+#        ifndef NO_ACTION_ONESHOT
+    set_oneshot_mods(serial_m2s_buffer.oneshot_mods);
+#        endif
+#    endif
 }
 
 #endif
diff --git a/quantum/split_common/transport.h b/quantum/split_common/transport.h
index c667bfab8..a9f66301b 100644
--- a/quantum/split_common/transport.h
+++ b/quantum/split_common/transport.h
@@ -6,5 +6,5 @@ void transport_master_init(void);
 void transport_slave_init(void);
 
 // returns false if valid data not received from slave
-bool transport_master(matrix_row_t matrix[]);
-void transport_slave(matrix_row_t matrix[]);
+bool transport_master(matrix_row_t master_matrix[], matrix_row_t slave_matrix[]);
+void transport_slave(matrix_row_t master_matrix[], matrix_row_t slave_matrix[]);