Make debounce() signal changes in the cooked matrix as return value (#17554)

11 files changed, 77 insertions, 33 deletions

diff --git a/quantum/debounce.h b/quantum/debounce.h
index 3532d9cd7b..a8629654c2 100644
--- a/quantum/debounce.h
+++ b/quantum/debounce.h
@@ -1,10 +1,16 @@
 #pragma once
 
-// raw is the current key state
-// on entry cooked is the previous debounced state
-// on exit cooked is the current debounced state
-// changed is true if raw has changed since the last call
-void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed);
+/**
+ * @brief Debounce raw matrix events according to the choosen debounce algorithm.
+ *
+ * @param raw The current key state
+ * @param cooked The debounced key state
+ * @param num_rows Number of rows to debounce
+ * @param changed True if raw has changed since the last call
+ * @return true Cooked has new keychanges after debouncing
+ * @return false Cooked is the same as before
+ */
+bool debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed);
 
 void debounce_init(uint8_t num_rows);
 
diff --git a/quantum/debounce/asym_eager_defer_pk.c b/quantum/debounce/asym_eager_defer_pk.c
index b1eb4a2b7b..4745c6f465 100644
--- a/quantum/debounce/asym_eager_defer_pk.c
+++ b/quantum/debounce/asym_eager_defer_pk.c
@@ -55,6 +55,7 @@ static debounce_counter_t *debounce_counters;
 static fast_timer_t        last_time;
 static bool                counters_need_update;
 static bool                matrix_need_update;
+static bool                cooked_changed;
 
 #    define DEBOUNCE_ELAPSED 0
 
@@ -77,8 +78,9 @@ void debounce_free(void) {
     debounce_counters = NULL;
 }
 
-void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
+bool debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
     bool updated_last = false;
+    cooked_changed    = false;
 
     if (counters_need_update) {
         fast_timer_t now          = timer_read_fast();
@@ -102,6 +104,8 @@ void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool
 
         transfer_matrix_values(raw, cooked, num_rows);
     }
+
+    return cooked_changed;
 }
 
 static void update_debounce_counters_and_transfer_if_expired(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, uint8_t elapsed_time) {
@@ -123,7 +127,9 @@ static void update_debounce_counters_and_transfer_if_expired(matrix_row_t raw[],
                         matrix_need_update = true;
                     } else {
                         // key-up: defer
-                        cooked[row] = (cooked[row] & ~col_mask) | (raw[row] & col_mask);
+                        matrix_row_t cooked_next = (cooked[row] & ~col_mask) | (raw[row] & col_mask);
+                        cooked_changed |= cooked_next ^ cooked[row];
+                        cooked[row] = cooked_next;
                     }
                 } else {
                     debounce_pointer->time -= elapsed_time;
@@ -152,6 +158,7 @@ static void transfer_matrix_values(matrix_row_t raw[], matrix_row_t cooked[], ui
                     if (debounce_pointer->pressed) {
                         // key-down: eager
                         cooked[row] ^= col_mask;
+                        cooked_changed = true;
                     }
                 }
             } else if (debounce_pointer->time != DEBOUNCE_ELAPSED) {
diff --git a/quantum/debounce/none.c b/quantum/debounce/none.c
index 8a85cc04a8..4cff5e05e2 100644
--- a/quantum/debounce/none.c
+++ b/quantum/debounce/none.c
@@ -17,13 +17,16 @@
 #include "matrix.h"
 #include "quantum.h"
 #include <stdlib.h>
+#include <string.h>
 
 void debounce_init(uint8_t num_rows) {}
 
-void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
-    for (int i = 0; i < num_rows; i++) {
-        cooked[i] = raw[i];
-    }
+bool debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
+    bool cooked_changed = memcmp(raw, cooked, sizeof(matrix_row_t) * num_rows) != 0;
+
+    memcpy(cooked, raw, sizeof(matrix_row_t) * num_rows);
+
+    return cooked_changed;
 }
 
 void debounce_free(void) {}
diff --git a/quantum/debounce/sym_defer_g.c b/quantum/debounce/sym_defer_g.c
index 47450992a4..d04310a761 100644
--- a/quantum/debounce/sym_defer_g.c
+++ b/quantum/debounce/sym_defer_g.c
@@ -20,6 +20,7 @@ When no state changes have occured for DEBOUNCE milliseconds, we push the state.
 #include "matrix.h"
 #include "timer.h"
 #include "quantum.h"
+#include <string.h>
 #ifndef DEBOUNCE
 #    define DEBOUNCE 5
 #endif
@@ -30,18 +31,23 @@ static fast_timer_t debouncing_time;
 
 void debounce_init(uint8_t num_rows) {}
 
-void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
+bool debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
+    bool cooked_changed = false;
+
     if (changed) {
         debouncing      = true;
         debouncing_time = timer_read_fast();
     }
 
     if (debouncing && timer_elapsed_fast(debouncing_time) >= DEBOUNCE) {
-        for (int i = 0; i < num_rows; i++) {
-            cooked[i] = raw[i];
+        if (memcmp(cooked, raw, sizeof(matrix_row_t) * num_rows) != 0) {
+            memcpy(cooked, raw, sizeof(matrix_row_t) * num_rows);
+            cooked_changed = true;
         }
         debouncing = false;
     }
+
+    return cooked_changed;
 }
 
 void debounce_free(void) {}
diff --git a/quantum/debounce/sym_defer_pk.c b/quantum/debounce/sym_defer_pk.c
index 9dee29e28e..7b59b5e100 100644
--- a/quantum/debounce/sym_defer_pk.c
+++ b/quantum/debounce/sym_defer_pk.c
@@ -48,6 +48,7 @@ typedef uint8_t debounce_counter_t;
 static debounce_counter_t *debounce_counters;
 static fast_timer_t        last_time;
 static bool                counters_need_update;
+static bool                cooked_changed;
 
 #    define DEBOUNCE_ELAPSED 0
 
@@ -70,8 +71,9 @@ void debounce_free(void) {
     debounce_counters = NULL;
 }
 
-void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
+bool debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
     bool updated_last = false;
+    cooked_changed    = false;
 
     if (counters_need_update) {
         fast_timer_t now          = timer_read_fast();
@@ -95,6 +97,8 @@ void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool
 
         start_debounce_counters(raw, cooked, num_rows);
     }
+
+    return cooked_changed;
 }
 
 static void update_debounce_counters_and_transfer_if_expired(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, uint8_t elapsed_time) {
@@ -104,8 +108,10 @@ static void update_debounce_counters_and_transfer_if_expired(matrix_row_t raw[],
         for (uint8_t col = 0; col < MATRIX_COLS; col++) {
             if (*debounce_pointer != DEBOUNCE_ELAPSED) {
                 if (*debounce_pointer <= elapsed_time) {
-                    *debounce_pointer = DEBOUNCE_ELAPSED;
-                    cooked[row]       = (cooked[row] & ~(ROW_SHIFTER << col)) | (raw[row] & (ROW_SHIFTER << col));
+                    *debounce_pointer        = DEBOUNCE_ELAPSED;
+                    matrix_row_t cooked_next = (cooked[row] & ~(ROW_SHIFTER << col)) | (raw[row] & (ROW_SHIFTER << col));
+                    cooked_changed |= cooked[row] ^ cooked_next;
+                    cooked[row] = cooked_next;
                 } else {
                     *debounce_pointer -= elapsed_time;
                     counters_need_update = true;
diff --git a/quantum/debounce/sym_defer_pr.c b/quantum/debounce/sym_defer_pr.c
index ce24f0922f..452c4599d0 100644
--- a/quantum/debounce/sym_defer_pr.c
+++ b/quantum/debounce/sym_defer_pr.c
@@ -46,11 +46,12 @@ void debounce_free(void) {
     last_raw = NULL;
 }
 
-void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
-    uint16_t now       = timer_read();
-    uint16_t elapsed16 = TIMER_DIFF_16(now, last_time);
-    last_time          = now;
-    uint8_t elapsed    = (elapsed16 > 255) ? 255 : elapsed16;
+bool debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
+    uint16_t now           = timer_read();
+    uint16_t elapsed16     = TIMER_DIFF_16(now, last_time);
+    last_time              = now;
+    uint8_t elapsed        = (elapsed16 > 255) ? 255 : elapsed16;
+    bool    cooked_changed = false;
 
     uint8_t* countdown = countdowns;
 
@@ -63,10 +64,13 @@ void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool
         } else if (*countdown > elapsed) {
             *countdown -= elapsed;
         } else if (*countdown) {
+            cooked_changed |= cooked[row] ^ raw_row;
             cooked[row] = raw_row;
             *countdown  = 0;
         }
     }
+
+    return cooked_changed;
 }
 
 bool debounce_active(void) {
diff --git a/quantum/debounce/sym_eager_pk.c b/quantum/debounce/sym_eager_pk.c
index fe3e88bb06..f736d1645c 100644
--- a/quantum/debounce/sym_eager_pk.c
+++ b/quantum/debounce/sym_eager_pk.c
@@ -49,6 +49,7 @@ static debounce_counter_t *debounce_counters;
 static fast_timer_t        last_time;
 static bool                counters_need_update;
 static bool                matrix_need_update;
+static bool                cooked_changed;
 
 #    define DEBOUNCE_ELAPSED 0
 
@@ -71,8 +72,9 @@ void debounce_free(void) {
     debounce_counters = NULL;
 }
 
-void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
+bool debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
     bool updated_last = false;
+    cooked_changed    = false;
 
     if (counters_need_update) {
         fast_timer_t now          = timer_read_fast();
@@ -96,6 +98,8 @@ void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool
 
         transfer_matrix_values(raw, cooked, num_rows);
     }
+
+    return cooked_changed;
 }
 
 // If the current time is > debounce counter, set the counter to enable input.
@@ -132,6 +136,7 @@ static void transfer_matrix_values(matrix_row_t raw[], matrix_row_t cooked[], ui
                     *debounce_pointer    = DEBOUNCE;
                     counters_need_update = true;
                     existing_row ^= col_mask; // flip the bit.
+                    cooked_changed = true;
                 }
             }
             debounce_pointer++;
diff --git a/quantum/debounce/sym_eager_pr.c b/quantum/debounce/sym_eager_pr.c
index 29b0cabefb..aad5ca351b 100644
--- a/quantum/debounce/sym_eager_pr.c
+++ b/quantum/debounce/sym_eager_pr.c
@@ -48,6 +48,7 @@ static bool matrix_need_update;
 static debounce_counter_t *debounce_counters;
 static fast_timer_t        last_time;
 static bool                counters_need_update;
+static bool                cooked_changed;
 
 #    define DEBOUNCE_ELAPSED 0
 
@@ -67,8 +68,9 @@ void debounce_free(void) {
     debounce_counters = NULL;
 }
 
-void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
+bool debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool changed) {
     bool updated_last = false;
+    cooked_changed    = false;
 
     if (counters_need_update) {
         fast_timer_t now          = timer_read_fast();
@@ -92,6 +94,8 @@ void debounce(matrix_row_t raw[], matrix_row_t cooked[], uint8_t num_rows, bool
 
         transfer_matrix_values(raw, cooked, num_rows);
     }
+
+    return cooked_changed;
 }
 
 // If the current time is > debounce counter, set the counter to enable input.
@@ -123,8 +127,9 @@ static void transfer_matrix_values(matrix_row_t raw[], matrix_row_t cooked[], ui
         // determine new value basd on debounce pointer + raw value
         if (existing_row != raw_row) {
             if (*debounce_pointer == DEBOUNCE_ELAPSED) {
-                *debounce_pointer    = DEBOUNCE;
-                cooked[row]          = raw_row;
+                *debounce_pointer = DEBOUNCE;
+                cooked[row]       = raw_row;
+                cooked_changed |= cooked[row] ^ raw[row];
                 counters_need_update = true;
             }
         }
diff --git a/quantum/debounce/tests/debounce_test_common.cpp b/quantum/debounce/tests/debounce_test_common.cpp
index 0d5a7bb766..bd98e32955 100644
--- a/quantum/debounce/tests/debounce_test_common.cpp
+++ b/quantum/debounce/tests/debounce_test_common.cpp
@@ -125,11 +125,15 @@ void DebounceTest::runDebounce(bool changed) {
     std::copy(std::begin(input_matrix_), std::end(input_matrix_), std::begin(raw_matrix_));
     std::copy(std::begin(output_matrix_), std::end(output_matrix_), std::begin(cooked_matrix_));
 
-    debounce(raw_matrix_, cooked_matrix_, MATRIX_ROWS, changed);
+    bool cooked_changed = debounce(raw_matrix_, cooked_matrix_, MATRIX_ROWS, changed);
 
     if (!std::equal(std::begin(input_matrix_), std::end(input_matrix_), std::begin(raw_matrix_))) {
         FAIL() << "Fatal error: debounce() modified raw matrix at " << strTime() << "\ninput_matrix: changed=" << changed << "\n" << strMatrix(input_matrix_) << "\nraw_matrix:\n" << strMatrix(raw_matrix_);
     }
+
+    if (std::equal(std::begin(output_matrix_), std::end(output_matrix_), std::begin(cooked_matrix_)) && cooked_changed) {
+        FAIL() << "Fatal error: debounce() did detect a wrong cooked matrix change at " << strTime() << "\noutput_matrix: cooked_changed=" << cooked_changed << "\n" << strMatrix(output_matrix_) << "\ncooked_matrix:\n" << strMatrix(cooked_matrix_);
+    }
 }
 
 void DebounceTest::checkCookedMatrix(bool changed, const std::string &error_message) {
diff --git a/quantum/matrix.c b/quantum/matrix.c
index db59b73754..db683104ed 100644
--- a/quantum/matrix.c
+++ b/quantum/matrix.c
@@ -337,10 +337,9 @@ uint8_t matrix_scan(void) {
     if (changed) memcpy(raw_matrix, curr_matrix, sizeof(curr_matrix));
 
 #ifdef SPLIT_KEYBOARD
-    debounce(raw_matrix, matrix + thisHand, ROWS_PER_HAND, changed);
-    changed = (changed || matrix_post_scan());
+    changed = debounce(raw_matrix, matrix + thisHand, ROWS_PER_HAND, changed) | matrix_post_scan();
 #else
-    debounce(raw_matrix, matrix, ROWS_PER_HAND, changed);
+    changed = debounce(raw_matrix, matrix, ROWS_PER_HAND, changed);
     matrix_scan_quantum();
 #endif
     return (uint8_t)changed;
diff --git a/quantum/matrix_common.c b/quantum/matrix_common.c
index 2cf8484347..68f0e38297 100644
--- a/quantum/matrix_common.c
+++ b/quantum/matrix_common.c
@@ -169,10 +169,9 @@ __attribute__((weak)) uint8_t matrix_scan(void) {
     bool changed = matrix_scan_custom(raw_matrix);
 
 #ifdef SPLIT_KEYBOARD
-    debounce(raw_matrix, matrix + thisHand, ROWS_PER_HAND, changed);
-    changed = (changed || matrix_post_scan());
+    changed = debounce(raw_matrix, matrix + thisHand, ROWS_PER_HAND, changed) | matrix_post_scan();
 #else
-    debounce(raw_matrix, matrix, ROWS_PER_HAND, changed);
+    changed = debounce(raw_matrix, matrix, ROWS_PER_HAND, changed);
     matrix_scan_quantum();
 #endif