From 9dfc611ae1903390a41b85da1cba2c6d67c7a8dd Mon Sep 17 00:00:00 2001
From: tmk <nobody@nowhere>
Date: Tue, 1 Jan 2013 03:20:53 +0900
Subject: [PATCH] Fix debouncing code.(gh60)

---
 keyboard/gh60/matrix.c | 55 +++++++++++++++++++++---------------------
 1 file changed, 27 insertions(+), 28 deletions(-)

diff --git a/keyboard/gh60/matrix.c b/keyboard/gh60/matrix.c
index 1a774e17..6ded8158 100644
--- a/keyboard/gh60/matrix.c
+++ b/keyboard/gh60/matrix.c
@@ -33,11 +33,12 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #endif
 static uint8_t debouncing = DEBOUNCE;
 
-// matrix state buffer(1:on, 0:off)
+/* matrix state(1:on, 0:off) */
 static uint16_t *matrix;
-static uint16_t *matrix_prev;
-static uint16_t _matrix0[MATRIX_ROWS];
-static uint16_t _matrix1[MATRIX_ROWS];
+static uint16_t *matrix_debouncing;
+static uint16_t matrix0[MATRIX_ROWS];
+static uint16_t matrix1[MATRIX_ROWS];
+static bool is_modified;
 
 static uint16_t read_cols(void);
 static void init_cols(void);
@@ -64,38 +65,42 @@ void matrix_init(void)
     init_cols();
 
     // initialize matrix state: all keys off
-    for (uint8_t i=0; i < MATRIX_ROWS; i++) _matrix0[i] = 0;
-    for (uint8_t i=0; i < MATRIX_ROWS; i++) _matrix1[i] = 0;
-    matrix = _matrix0;
-    matrix_prev = _matrix1;
+    matrix = matrix0;
+    matrix_debouncing = matrix1;
+    for (uint8_t i=0; i < MATRIX_ROWS; i++) {
+        matrix[i] = 0;
+        matrix_debouncing[i] = 0;
+    }
+    is_modified = false;
 }
 
 uint8_t matrix_scan(void)
 {
-    if (!debouncing) {
-        uint16_t *tmp = matrix_prev;
-        matrix_prev = matrix;
-        matrix = tmp;
-    }
-
     for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
-        unselect_rows();
+        //unselect_rows();
         select_row(i);
-        _delay_us(1);  // without this wait read unstable value.
+        _delay_us(30);  // without this wait read unstable value.
         uint16_t cols = read_cols();
-        if (matrix[i] != cols) {
-            matrix[i] = cols;
+        if (matrix_debouncing[i] != cols) {
+            matrix_debouncing[i] = cols;
             if (debouncing) {
-                debug("bounce!: "); debug_hex(debouncing); print("\n");
+                debug("bounce!: "); debug_hex(debouncing); debug("\n");
             }
             debouncing = DEBOUNCE;
+            is_modified = false;
         }
+        unselect_rows();
     }
-    unselect_rows();
+    //unselect_rows();
 
     if (debouncing) {
         debouncing--;
-        _delay_ms(1); // improved affect on bouncing
+        _delay_ms(1);
+    } else {
+        uint16_t *tmp = matrix;
+        matrix = matrix_debouncing;
+        matrix_debouncing = tmp;
+        is_modified = true;
     }
 
     return 1;
@@ -103,13 +108,7 @@ uint8_t matrix_scan(void)
 
 bool matrix_is_modified(void)
 {
-    if (debouncing) return false;
-    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
-        if (matrix[i] != matrix_prev[i]) {
-            return true;
-        }
-    }
-    return false;
+    return is_modified;
 }
 
 inline