From ac2e6e01f155811d0e206298f0d7cadcc9234603 Mon Sep 17 00:00:00 2001
From: Takeshi ISHII <2170248+mtei@users.noreply.github.com>
Date: Tue, 13 Jul 2021 16:50:25 +0900
Subject: [PATCH] Change the prototype of matrix_output_unselect_delay()
 (#13045)

The prototype of matrix_output_unselect_delay() has been changed as follows.

```c
void matrix_output_unselect_delay(uint8_t line, bool key_pressed);
```

Currently, no keyboard seems to be redefining `matrix_output_unselect_delay()`, so there is no change in the system behavior.

With this change, the keyboard level code can get some optimization hints, for example, the following.

```c
 void matrix_output_unselect_delay(uint8_t line, bool key_pressed) {
     /* If none of the keys are pressed,
      *  there is no need to wait for time for the next line. */
     if (key_pressed) {
 #ifdef MATRIX_IO_DELAY
 #  if MATRIX_IO_DELAY > 0
         wait_us(MATRIX_IO_DELAY);
 #  endif
 #else
         wait_us(30);
 #endif
     }
}
```
---
 quantum/matrix.c        | 7 +++++--
 quantum/matrix.h        | 2 +-
 quantum/matrix_common.c | 2 +-
 3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/quantum/matrix.c b/quantum/matrix.c
index 235b16769f1..d22817bf48e 100644
--- a/quantum/matrix.c
+++ b/quantum/matrix.c
@@ -182,7 +182,7 @@ __attribute__((weak)) void matrix_read_cols_on_row(matrix_row_t current_matrix[]
 
     // Unselect row
     unselect_row(current_row);
-    matrix_output_unselect_delay();  // wait for all Col signals to go HIGH
+    matrix_output_unselect_delay(current_row, current_row_value != 0);  // wait for all Col signals to go HIGH
 
     // Update the matrix
     current_matrix[current_row] = current_row_value;
@@ -222,6 +222,8 @@ __attribute__((weak)) void matrix_init_pins(void) {
 }
 
 __attribute__((weak)) void matrix_read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col) {
+    bool key_pressed = false;
+
     // Select col
     if (!select_col(current_col)) {  // select col
         return;                      // skip NO_PIN col
@@ -234,6 +236,7 @@ __attribute__((weak)) void matrix_read_rows_on_col(matrix_row_t current_matrix[]
         if (readMatrixPin(row_pins[row_index]) == 0) {
             // Pin LO, set col bit
             current_matrix[row_index] |= (MATRIX_ROW_SHIFTER << current_col);
+            key_pressed = true;
         } else {
             // Pin HI, clear col bit
             current_matrix[row_index] &= ~(MATRIX_ROW_SHIFTER << current_col);
@@ -242,7 +245,7 @@ __attribute__((weak)) void matrix_read_rows_on_col(matrix_row_t current_matrix[]
 
     // Unselect col
     unselect_col(current_col);
-    matrix_output_unselect_delay();  // wait for all Row signals to go HIGH
+    matrix_output_unselect_delay(current_col, key_pressed);  // wait for all Row signals to go HIGH
 }
 
 #        else
diff --git a/quantum/matrix.h b/quantum/matrix.h
index 3fe691aaee6..5c696622fcf 100644
--- a/quantum/matrix.h
+++ b/quantum/matrix.h
@@ -56,7 +56,7 @@ matrix_row_t matrix_get_row(uint8_t row);
 void matrix_print(void);
 /* delay between changing matrix pin state and reading values */
 void matrix_output_select_delay(void);
-void matrix_output_unselect_delay(void);
+void matrix_output_unselect_delay(uint8_t line, bool key_pressed);
 /* only for backwards compatibility. delay between changing matrix pin state and reading values */
 void matrix_io_delay(void);
 
diff --git a/quantum/matrix_common.c b/quantum/matrix_common.c
index efbad6a5fd1..66c89970b10 100644
--- a/quantum/matrix_common.c
+++ b/quantum/matrix_common.c
@@ -88,7 +88,7 @@ uint8_t matrix_key_count(void) {
 __attribute__((weak)) void matrix_io_delay(void) { wait_us(MATRIX_IO_DELAY); }
 
 __attribute__((weak)) void matrix_output_select_delay(void) { waitInputPinDelay(); }
-__attribute__((weak)) void matrix_output_unselect_delay(void) { matrix_io_delay(); }
+__attribute__((weak)) void matrix_output_unselect_delay(uint8_t line, bool key_pressed) { matrix_io_delay(); }
 
 // CUSTOM MATRIX 'LITE'
 __attribute__((weak)) void matrix_init_custom(void) {}