Simplify split_common Code significantly (#4772)

* Eliminate separate slave loop

Both master and slave run the standard keyboard_task main loop now.

* Refactor i2c/serial specific code

Simplify some of the preprocessor mess by using common function names.

* Fix missing #endif

* Move direct pin mapping support from miniaxe to split_common

For boards with more pins than sense--sorry, switches.

* Reordering and reformatting only

* Don't run matrix_scan_quantum on slave side

* Clean up the offset/slaveOffset calculations

* Cut undebounced matrix size in half

* Refactor debouncing

* Minor fixups

* Split split_common transport and debounce code into their own files

Can now be replaced with custom versions per keyboard using
CUSTOM_TRANSPORT = yes and CUSTOM_DEBOUNCE = yes

* Refactor debounce for non-split keyboards too

* Update handwired/xealous to build using new split_common

* Fix debounce breaking basic test

* Dodgy method to allow a split kb to only include one of i2c/serial

SPLIT_TRANSPORT = serial or SPLIT_TRANSPORT = i2c will include only
that driver code in the binary.

SPLIT_TRANSPORT = custom (or anything else) will include neither, the
keyboard must supply it's own code

if SPLIT_TRANSPORT is not defined then the original behaviour (include
both avr i2c and serial code) is maintained.

This could be better but it would require explicitly updating all the
existing split keyboards.

* Enable LTO to get lets_split/sockets under the line

* Add docs for SPLIT_TRANSPORT, CUSTOM_MATRIX, CUSTOM_DEBOUNCE

* Remove avr-specific sei() from split matrix_setup

Not needed now that slave doesn't have a separate main loop.
Both sides (on avr) call sei() in lufa's main() after exiting
keyboard_setup().

* Fix QUANTUM_LIB_SRC references and simplify SPLIT_TRANSPORT.

* Add comments and fix formatting.

3 files changed, 3 insertions, 646 deletions

diff --git a/keyboards/miniaxe/config.h b/keyboards/miniaxe/config.h
index 2b732ca16f..7a68476a54 100644
--- a/keyboards/miniaxe/config.h
+++ b/keyboards/miniaxe/config.h
@@ -44,8 +44,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 // #define MATRIX_ROW_PINS { D0, D5 }
 // #define MATRIX_COL_PINS { F1, F0, B0 }
-#define NO_PIN 0xFF
-#define MATRIX_ROW_COL_PINS { \
+#define DIRECT_PINS { \
     { F1, E6, B0, B2, B3 }, \
     { F5, F0, B1, B7, D2 }, \
     { F6, F7, C7, D5, D3 }, \
@@ -54,7 +53,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define UNUSED_PINS
 
 /* COL2ROW, ROW2COL, or CUSTOM_MATRIX */
-#define DIODE_DIRECTION CUSTOM_MATRIX
+//#define DIODE_DIRECTION CUSTOM_MATRIX
 
 // #define BACKLIGHT_PIN B7
 // #define BACKLIGHT_BREATHING
diff --git a/keyboards/miniaxe/matrix.c b/keyboards/miniaxe/matrix.c
deleted file mode 100644
index 5fec1281df..0000000000
--- a/keyboards/miniaxe/matrix.c
+++ /dev/null
@@ -1,641 +0,0 @@
-/*
-Copyright 2012 Jun Wako <wakojun@gmail.com>
-
-This program is free software: you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation, either version 2 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-/*
- * scan matrix
- */
-#include <stdint.h>
-#include <stdbool.h>
-#include <avr/io.h>
-#include "wait.h"
-#include "print.h"
-#include "debug.h"
-#include "util.h"
-#include "matrix.h"
-#include "split_util.h"
-#include "pro_micro.h"
-#include "config.h"
-#include "timer.h"
-#include "split_flags.h"
-
-#ifdef BACKLIGHT_ENABLE
-#   include "backlight.h"
-    extern backlight_config_t backlight_config;
-#endif
-
-#if defined(USE_I2C) || defined(EH)
-#  include "i2c.h"
-#else // USE_SERIAL
-#  include "serial.h"
-#endif
-
-#ifndef DEBOUNCING_DELAY
-#   define DEBOUNCING_DELAY 5
-#endif
-
-#if (DEBOUNCING_DELAY > 0)
-    static uint16_t debouncing_time;
-    static bool debouncing = false;
-#endif
-
-#if defined(USE_I2C) || defined(EH)
-
-#if (MATRIX_COLS <= 8)
-#    define print_matrix_header()  print("\nr/c 01234567\n")
-#    define print_matrix_row(row)  print_bin_reverse8(matrix_get_row(row))
-#    define matrix_bitpop(i)       bitpop(matrix[i])
-#    define ROW_SHIFTER ((uint8_t)1)
-#else
-#    error "Currently only supports 8 COLS"
-#endif
-
-#else // USE_SERIAL
-
-#if (MATRIX_COLS <= 8)
-#    define print_matrix_header()  print("\nr/c 01234567\n")
-#    define print_matrix_row(row)  print_bin_reverse8(matrix_get_row(row))
-#    define matrix_bitpop(i)       bitpop(matrix[i])
-#    define ROW_SHIFTER ((uint8_t)1)
-#elif (MATRIX_COLS <= 16)
-#    define print_matrix_header()  print("\nr/c 0123456789ABCDEF\n")
-#    define print_matrix_row(row)  print_bin_reverse16(matrix_get_row(row))
-#    define matrix_bitpop(i)       bitpop16(matrix[i])
-#    define ROW_SHIFTER ((uint16_t)1)
-#elif (MATRIX_COLS <= 32)
-#    define print_matrix_header()  print("\nr/c 0123456789ABCDEF0123456789ABCDEF\n")
-#    define print_matrix_row(row)  print_bin_reverse32(matrix_get_row(row))
-#    define matrix_bitpop(i)       bitpop32(matrix[i])
-#    define ROW_SHIFTER  ((uint32_t)1)
-#endif
-
-#endif
-static matrix_row_t matrix_debouncing[MATRIX_ROWS];
-
-#define ERROR_DISCONNECT_COUNT 5
-
-#define ROWS_PER_HAND (MATRIX_ROWS/2)
-
-static uint8_t error_count = 0;
-
-#if ((DIODE_DIRECTION == COL2ROW) || (DIODE_DIRECTION == ROW2COL))
-static uint8_t row_pins[MATRIX_ROWS] = MATRIX_ROW_PINS;
-static uint8_t col_pins[MATRIX_COLS] = MATRIX_COL_PINS;
-#elif (DIODE_DIRECTION == CUSTOM_MATRIX)
-static uint8_t row_col_pins[MATRIX_ROWS][MATRIX_COLS] = MATRIX_ROW_COL_PINS;
-#endif
-
-/* matrix state(1:on, 0:off) */
-static matrix_row_t matrix[MATRIX_ROWS];
-static matrix_row_t matrix_debouncing[MATRIX_ROWS];
-
-#if (DIODE_DIRECTION == COL2ROW)
-    static void init_cols(void);
-    static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row);
-    static void unselect_rows(void);
-    static void select_row(uint8_t row);
-    static void unselect_row(uint8_t row);
-#elif (DIODE_DIRECTION == ROW2COL)
-    static void init_rows(void);
-    static bool read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col);
-    static void unselect_cols(void);
-    static void unselect_col(uint8_t col);
-    static void select_col(uint8_t col);
-#elif (DIODE_DIRECTION == CUSTOM_MATRIX)
-    static void init_cols_rows(void);
-    static bool read_cols(matrix_row_t current_matrix[], uint8_t current_row);
-#endif
-
-__attribute__ ((weak))
-void matrix_init_kb(void) {
-    matrix_init_user();
-}
-
-__attribute__ ((weak))
-void matrix_scan_kb(void) {
-    matrix_scan_user();
-}
-
-__attribute__ ((weak))
-void matrix_init_user(void) {
-}
-
-__attribute__ ((weak))
-void matrix_scan_user(void) {
-}
-
-__attribute__ ((weak))
-void matrix_slave_scan_user(void) {
-}
-
-inline
-uint8_t matrix_rows(void)
-{
-    return MATRIX_ROWS;
-}
-
-inline
-uint8_t matrix_cols(void)
-{
-    return MATRIX_COLS;
-}
-
-void matrix_init(void)
-{
-#ifdef DISABLE_JTAG
-  // JTAG disable for PORT F. write JTD bit twice within four cycles.
-  MCUCR |= (1<<JTD);
-  MCUCR |= (1<<JTD);
-#endif
-
-    debug_enable = true;
-    debug_matrix = true;
-    debug_mouse = true;
-
-    // Set pinout for right half if pinout for that half is defined
-    if (!isLeftHand) {
-#ifdef MATRIX_ROW_PINS_RIGHT
-        const uint8_t row_pins_right[MATRIX_ROWS] = MATRIX_ROW_PINS_RIGHT;
-        for (uint8_t i = 0; i < MATRIX_ROWS; i++)
-            row_pins[i] = row_pins_right[i];
-#endif
-#ifdef MATRIX_COL_PINS_RIGHT
-        const uint8_t col_pins_right[MATRIX_COLS] = MATRIX_COL_PINS_RIGHT;
-        for (uint8_t i = 0; i < MATRIX_COLS; i++)
-            col_pins[i] = col_pins_right[i];
-#endif
-    }
-
-    // initialize row and col
-#if (DIODE_DIRECTION == COL2ROW)
-    unselect_rows();
-    init_cols();
-#elif (DIODE_DIRECTION == ROW2COL)
-    unselect_cols();
-    init_rows();
-#elif (DIODE_DIRECTION == CUSTOM_MATRIX)
-    init_cols_rows();
-#endif
-
-    // initialize matrix state: all keys off
-    for (uint8_t i=0; i < MATRIX_ROWS; i++) {
-        matrix[i] = 0;
-        matrix_debouncing[i] = 0;
-    }
-    
-    matrix_init_quantum();
-    
-}
-
-uint8_t _matrix_scan(void)
-{
-    int offset = isLeftHand ? 0 : (ROWS_PER_HAND);
-#if (DIODE_DIRECTION == COL2ROW)
-    // Set row, read cols
-    for (uint8_t current_row = 0; current_row < ROWS_PER_HAND; current_row++) {
-#       if (DEBOUNCING_DELAY > 0)
-            bool matrix_changed = read_cols_on_row(matrix_debouncing+offset, current_row);
-
-            if (matrix_changed) {
-                debouncing = true;
-                debouncing_time = timer_read();
-            }
-
-#       else
-            read_cols_on_row(matrix+offset, current_row);
-#       endif
-
-    }
-
-#elif (DIODE_DIRECTION == ROW2COL)
-    // Set col, read rows
-    for (uint8_t current_col = 0; current_col < MATRIX_COLS; current_col++) {
-#       if (DEBOUNCING_DELAY > 0)
-            bool matrix_changed = read_rows_on_col(matrix_debouncing+offset, current_col);
-            if (matrix_changed) {
-                debouncing = true;
-                debouncing_time = timer_read();
-            }
-#       else
-             read_rows_on_col(matrix+offset, current_col);
-#       endif
-
-    }
-
-#elif (DIODE_DIRECTION == CUSTOM_MATRIX)
-    // Set row, read cols
-    for (uint8_t current_row = 0; current_row < ROWS_PER_HAND; current_row++) {
-#       if (DEBOUNCING_DELAY > 0)
-            bool matrix_changed = read_cols(matrix_debouncing+offset, current_row);
-            if (matrix_changed) {
-                debouncing = true;
-                debouncing_time = timer_read();
-            }
-#       else
-            read_cols(matrix+offset, current_row);
-#       endif
-    }
-#endif
-
-#   if (DEBOUNCING_DELAY > 0)
-        if (debouncing && (timer_elapsed(debouncing_time) > DEBOUNCING_DELAY)) {
-            for (uint8_t i = 0; i < ROWS_PER_HAND; i++) {
-                matrix[i+offset] = matrix_debouncing[i+offset];
-            }
-            debouncing = false;
-        }
-#   endif
-
-    return 1;
-}
-
-#if defined(USE_I2C) || defined(EH)
-
-// Get rows from other half over i2c
-int i2c_transaction(void) {
-    int slaveOffset = (isLeftHand) ? (ROWS_PER_HAND) : 0;
-    int err = 0;
-    
-    // write backlight info
-    #ifdef BACKLIGHT_ENABLE
-        if (BACKLIT_DIRTY) {
-            err = i2c_master_start(SLAVE_I2C_ADDRESS + I2C_WRITE);
-            if (err) goto i2c_error;
-            
-            // Backlight location
-            err = i2c_master_write(I2C_BACKLIT_START);
-            if (err) goto i2c_error;
-            
-            // Write backlight 
-            i2c_master_write(get_backlight_level());
-            
-            BACKLIT_DIRTY = false;
-        }
-    #endif
-
-    err = i2c_master_start(SLAVE_I2C_ADDRESS + I2C_WRITE);
-    if (err) goto i2c_error;
-
-    // start of matrix stored at I2C_KEYMAP_START
-    err = i2c_master_write(I2C_KEYMAP_START);
-    if (err) goto i2c_error;
-
-    // Start read
-    err = i2c_master_start(SLAVE_I2C_ADDRESS + I2C_READ);
-    if (err) goto i2c_error;
-
-    if (!err) {
-        int i;
-        for (i = 0; i < ROWS_PER_HAND-1; ++i) {
-            matrix[slaveOffset+i] = i2c_master_read(I2C_ACK);
-        }
-        matrix[slaveOffset+i] = i2c_master_read(I2C_NACK);
-        i2c_master_stop();
-    } else {
-i2c_error: // the cable is disconnceted, or something else went wrong
-        i2c_reset_state();
-        return err;
-    }
-    
-    #ifdef RGBLIGHT_ENABLE
-        if (RGB_DIRTY) {
-            err = i2c_master_start(SLAVE_I2C_ADDRESS + I2C_WRITE);
-            if (err) goto i2c_error;
-            
-            // RGB Location
-            err = i2c_master_write(I2C_RGB_START);
-            if (err) goto i2c_error;
-            
-            uint32_t dword = eeconfig_read_rgblight();
-            
-            // Write RGB
-            err = i2c_master_write_data(&dword, 4);
-            if (err) goto i2c_error;
-            
-            RGB_DIRTY = false;
-            i2c_master_stop();
-        }
-    #endif
-
-    return 0;
-}
-
-#else // USE_SERIAL
-
-
-typedef struct _Serial_s2m_buffer_t {
-    // TODO: if MATRIX_COLS > 8 change to uint8_t packed_matrix[] for pack/unpack
-    matrix_row_t smatrix[ROWS_PER_HAND];
-} Serial_s2m_buffer_t;
-
-volatile Serial_s2m_buffer_t serial_s2m_buffer = {};
-volatile Serial_m2s_buffer_t serial_m2s_buffer = {};
-uint8_t volatile status0 = 0;
-
-SSTD_t transactions[] = {
-    { (uint8_t *)&status0,
-      sizeof(serial_m2s_buffer), (uint8_t *)&serial_m2s_buffer,
-      sizeof(serial_s2m_buffer), (uint8_t *)&serial_s2m_buffer
-  }
-};
-
-void serial_master_init(void)
-{ soft_serial_initiator_init(transactions, TID_LIMIT(transactions)); }
-
-void serial_slave_init(void)
-{ soft_serial_target_init(transactions, TID_LIMIT(transactions)); }
-
-int serial_transaction(void) {
-    int slaveOffset = (isLeftHand) ? (ROWS_PER_HAND) : 0;
-
-    if (soft_serial_transaction()) {
-        return 1;
-    }
-
-    // TODO:  if MATRIX_COLS > 8 change to unpack()
-    for (int i = 0; i < ROWS_PER_HAND; ++i) {
-        matrix[slaveOffset+i] = serial_s2m_buffer.smatrix[i];
-    }
-    
-    #ifdef RGBLIGHT_ENABLE
-        // Code to send RGB over serial goes here (not implemented yet)
-    #endif
-    
-    #ifdef BACKLIGHT_ENABLE
-        // Write backlight level for slave to read
-        serial_m2s_buffer.backlight_level = backlight_config.enable ? backlight_config.level : 0;
-    #endif
-
-    return 0;
-}
-#endif
-
-uint8_t matrix_scan(void)
-{
-    uint8_t ret = _matrix_scan();
-
-#if defined(USE_I2C) || defined(EH)
-    if( i2c_transaction() ) {
-#else // USE_SERIAL
-    if( serial_transaction() ) {
-#endif
-
-        error_count++;
-
-        if (error_count > ERROR_DISCONNECT_COUNT) {
-            // reset other half if disconnected
-            int slaveOffset = (isLeftHand) ? (ROWS_PER_HAND) : 0;
-            for (int i = 0; i < ROWS_PER_HAND; ++i) {
-                matrix[slaveOffset+i] = 0;
-            }
-        }
-    } else {
-        error_count = 0;
-    }
-    matrix_scan_quantum();
-    return ret;
-}
-
-void matrix_slave_scan(void) {
-    _matrix_scan();
-
-    int offset = (isLeftHand) ? 0 : ROWS_PER_HAND;
-
-#if defined(USE_I2C) || defined(EH)
-    for (int i = 0; i < ROWS_PER_HAND; ++i) {
-        i2c_slave_buffer[I2C_KEYMAP_START+i] = matrix[offset+i];
-    }   
-#else // USE_SERIAL
-    // TODO: if MATRIX_COLS > 8 change to pack()
-    for (int i = 0; i < ROWS_PER_HAND; ++i) {
-        serial_s2m_buffer.smatrix[i] = matrix[offset+i];
-    }
-#endif
-    matrix_slave_scan_user();
-}
-
-bool matrix_is_modified(void)
-{
-    if (debouncing) return false;
-    return true;
-}
-
-inline
-bool matrix_is_on(uint8_t row, uint8_t col)
-{
-    return (matrix[row] & ((matrix_row_t)1<<col));
-}
-
-inline
-matrix_row_t matrix_get_row(uint8_t row)
-{
-    return matrix[row];
-}
-
-void matrix_print(void)
-{
-    print("\nr/c 0123456789ABCDEF\n");
-    for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
-        phex(row); print(": ");
-        pbin_reverse16(matrix_get_row(row));
-        print("\n");
-    }
-}
-
-uint8_t matrix_key_count(void)
-{
-    uint8_t count = 0;
-    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
-        count += bitpop16(matrix[i]);
-    }
-    return count;
-}
-
-#if (DIODE_DIRECTION == COL2ROW)
-
-static void init_cols(void)
-{
-    for(uint8_t x = 0; x < MATRIX_COLS; x++) {
-        uint8_t pin = col_pins[x];
-        _SFR_IO8((pin >> 4) + 1) &= ~_BV(pin & 0xF); // IN
-        _SFR_IO8((pin >> 4) + 2) |=  _BV(pin & 0xF); // HI
-    }
-}
-
-static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row)
-{
-    // Store last value of row prior to reading
-    matrix_row_t last_row_value = current_matrix[current_row];
-
-    // Clear data in matrix row
-    current_matrix[current_row] = 0;
-
-    // Select row and wait for row selecton to stabilize
-    select_row(current_row);
-    wait_us(30);
-
-    // For each col...
-    for(uint8_t col_index = 0; col_index < MATRIX_COLS; col_index++) {
-
-        // Select the col pin to read (active low)
-        uint8_t pin = col_pins[col_index];
-        uint8_t pin_state = (_SFR_IO8(pin >> 4) & _BV(pin & 0xF));
-
-        // Populate the matrix row with the state of the col pin
-        current_matrix[current_row] |=  pin_state ? 0 : (ROW_SHIFTER << col_index);
-    }
-
-    // Unselect row
-    unselect_row(current_row);
-
-    return (last_row_value != current_matrix[current_row]);
-}
-
-static void select_row(uint8_t row)
-{
-    uint8_t pin = row_pins[row];
-    _SFR_IO8((pin >> 4) + 1) |=  _BV(pin & 0xF); // OUT
-    _SFR_IO8((pin >> 4) + 2) &= ~_BV(pin & 0xF); // LOW
-}
-
-static void unselect_row(uint8_t row)
-{
-    uint8_t pin = row_pins[row];
-    _SFR_IO8((pin >> 4) + 1) &= ~_BV(pin & 0xF); // IN
-    _SFR_IO8((pin >> 4) + 2) |=  _BV(pin & 0xF); // HI
-}
-
-static void unselect_rows(void)
-{
-    for(uint8_t x = 0; x < ROWS_PER_HAND; x++) {
-        uint8_t pin = row_pins[x];
-        _SFR_IO8((pin >> 4) + 1) &= ~_BV(pin & 0xF); // IN
-        _SFR_IO8((pin >> 4) + 2) |=  _BV(pin & 0xF); // HI
-    }
-}
-
-#elif (DIODE_DIRECTION == ROW2COL)
-
-static void init_rows(void)
-{
-    for(uint8_t x = 0; x < ROWS_PER_HAND; x++) {
-        uint8_t pin = row_pins[x];
-        _SFR_IO8((pin >> 4) + 1) &= ~_BV(pin & 0xF); // IN
-        _SFR_IO8((pin >> 4) + 2) |=  _BV(pin & 0xF); // HI
-    }
-}
-
-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(current_col);
-    wait_us(30);
-
-    // For each row...
-    for(uint8_t row_index = 0; row_index < ROWS_PER_HAND; row_index++)
-    {
-
-        // Store last value of row prior to reading
-        matrix_row_t last_row_value = current_matrix[row_index];
-
-        // Check row pin state
-        if ((_SFR_IO8(row_pins[row_index] >> 4) & _BV(row_pins[row_index] & 0xF)) == 0)
-        {
-            // Pin LO, set col bit
-            current_matrix[row_index] |= (ROW_SHIFTER << current_col);
-        }
-        else
-        {
-            // Pin HI, clear col bit
-            current_matrix[row_index] &= ~(ROW_SHIFTER << current_col);
-        }
-
-        // Determine if the matrix changed state
-        if ((last_row_value != current_matrix[row_index]) && !(matrix_changed))
-        {
-            matrix_changed = true;
-        }
-    }
-
-    // Unselect col
-    unselect_col(current_col);
-
-    return matrix_changed;
-}
-
-static void select_col(uint8_t col)
-{
-    uint8_t pin = col_pins[col];
-    _SFR_IO8((pin >> 4) + 1) |=  _BV(pin & 0xF); // OUT
-    _SFR_IO8((pin >> 4) + 2) &= ~_BV(pin & 0xF); // LOW
-}
-
-static void unselect_col(uint8_t col)
-{
-    uint8_t pin = col_pins[col];
-    _SFR_IO8((pin >> 4) + 1) &= ~_BV(pin & 0xF); // IN
-    _SFR_IO8((pin >> 4) + 2) |=  _BV(pin & 0xF); // HI
-}
-
-static void unselect_cols(void)
-{
-    for(uint8_t x = 0; x < MATRIX_COLS; x++) {
-        uint8_t pin = col_pins[x];
-        _SFR_IO8((pin >> 4) + 1) &= ~_BV(pin & 0xF); // IN
-        _SFR_IO8((pin >> 4) + 2) |=  _BV(pin & 0xF); // HI
-    }
-}
-
-#elif (DIODE_DIRECTION == CUSTOM_MATRIX)
-
-static void init_cols_rows(void)
-{
-    for(int row = 0; row < MATRIX_ROWS; row++) {
-        for(int col = 0; col < MATRIX_COLS; col++) {
-            uint8_t pin = row_col_pins[row][col];
-            if(pin == NO_PIN) {
-                continue;
-            }
-            // DDxn set 0 for input
-            _SFR_IO8((pin >> 4) + 1) &=  ~_BV(pin & 0xF);
-            // PORTxn set 1 for input/pullup
-            _SFR_IO8((pin >> 4) + 2) |= _BV(pin & 0xF);
-        }
-    }
-}
-
-static bool read_cols(matrix_row_t current_matrix[], uint8_t current_row)
-{
-    matrix_row_t last_row_value = current_matrix[current_row];
-    current_matrix[current_row] = 0;
-
-    for(uint8_t col_index = 0; col_index < MATRIX_COLS; col_index++) {
-        uint8_t pin = row_col_pins[current_row][col_index];
-        if(pin == NO_PIN) {
-            current_matrix[current_row] |= 0;
-        }
-        else {
-            uint8_t pin_state = (_SFR_IO8(pin >> 4) & _BV(pin & 0xF));
-            current_matrix[current_row] |= pin_state ? 0 : (ROW_SHIFTER << col_index);
-        }
-    }
-
-    return (last_row_value != current_matrix[current_row]);
-}
-
-#endif
diff --git a/keyboards/miniaxe/rules.mk b/keyboards/miniaxe/rules.mk
index 96e27686b8..2f56a907ba 100644
--- a/keyboards/miniaxe/rules.mk
+++ b/keyboards/miniaxe/rules.mk
@@ -1,4 +1,3 @@
-SRC += matrix.c
 
 # MCU name
 #MCU = at90usb1286
@@ -83,6 +82,6 @@ FAUXCLICKY_ENABLE = no      # Use buzzer to emulate clicky switches
 HD44780_ENABLE = no 		# Enable support for HD44780 based LCDs (+400)
 
 DEBUG_ENABLE = no
-CUSTOM_MATRIX = yes         # Use custom matrix code 
+CUSTOM_MATRIX = no         # Use custom matrix code
 SPLIT_KEYBOARD = yes        # Use shared split_common code