Keyboard: Port of TMK XT USB Converter (#3619)

* Converter: add XT USB converter from TMK

* Converter: port TMK code for USB converter to QMK

* Apply requested changes after code review by @drashna

- use "pragma once" instead of include guards
- use LAYOUT instead of KEYMAP
- allow customisation with matrix_init_user() and matrix_scan_user()
- set BOOTLOADER instead of BOOTLOADER_SIZE
- Add XT_ENABLE to OPT_DEFS

* Remove unnecessary lines

1 files changed, 309 insertions, 0 deletions

diff --git a/keyboards/converter/xt_usb/matrix.c b/keyboards/converter/xt_usb/matrix.c
new file mode 100644
index 0000000000..e2d7117b13
--- /dev/null
+++ b/keyboards/converter/xt_usb/matrix.c
@@ -0,0 +1,309 @@
+/*
+Copyright 2011 Jun Wako <wakojun@gmail.com>
+Copyright 2016 Ethan Apodaca <papodaca@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/>.
+*/
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "action.h"
+#include "print.h"
+#include "util.h"
+#include "debug.h"
+#include "xt.h"
+#include "matrix.h"
+
+
+static void matrix_make(uint8_t code);
+static void matrix_break(uint8_t code);
+
+static uint8_t matrix[MATRIX_ROWS];
+#define ROW(code)      (code>>3)
+#define COL(code)      (code&0x07)
+
+__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) {
+}
+
+void matrix_init(void)
+{
+    debug_enable = true;
+    xt_host_init();
+
+    // initialize matrix state: all keys off
+    for (uint8_t i=0; i < MATRIX_ROWS; i++) matrix[i] = 0x00;
+
+    matrix_init_quantum();
+}
+
+// convert E0-escaped codes into unused area
+static uint8_t move_e0code(uint8_t code) {
+    switch(code) {
+        // Original IBM XT keyboard has these keys
+        case 0x37: return 0x54; // Print Screen
+        case 0x46: return 0x55; // Ctrl + Pause
+        case 0x1C: return 0x6F; // Keypad Enter
+        case 0x35: return 0x7F; // Keypad /
+
+        // Any XT keyobard with these keys?
+        // http://download.microsoft.com/download/1/6/1/161ba512-40e2-4cc9-843a-923143f3456c/translate.pdf
+        // https://download.microsoft.com/download/1/6/1/161ba512-40e2-4cc9-843a-923143f3456c/scancode.doc
+        case 0x5B: return 0x5A; // Left  GUI
+        case 0x5C: return 0x5B; // Right GUI
+        case 0x5D: return 0x5C; // Application
+        case 0x5E: return 0x5D; // Power(not used)
+        case 0x5F: return 0x5E; // Sleep(not used)
+        case 0x63: return 0x5F; // Wake (not used)
+        case 0x48: return 0x60; // Up
+        case 0x4B: return 0x61; // Left
+        case 0x50: return 0x62; // Down
+        case 0x4D: return 0x63; // Right
+        case 0x52: return 0x71; // Insert
+        case 0x53: return 0x72; // Delete
+        case 0x47: return 0x74; // Home
+        case 0x4F: return 0x75; // End
+        case 0x49: return 0x77; // Home
+        case 0x51: return 0x78; // End
+        case 0x1D: return 0x7A; // Right Ctrl
+        case 0x38: return 0x7C; // Right Alt
+    }
+    return 0x00;
+}
+
+uint8_t matrix_scan(void)
+{
+    static enum {
+        INIT,
+        E0,
+        // Pause: E1 1D 45, E1 9D C5
+        E1,
+        E1_1D,
+        E1_9D,
+    } state = INIT;
+
+    uint8_t code = xt_host_recv();
+    if (!code) return 0;
+    xprintf("%02X ", code);
+    switch (state) {
+        case INIT:
+            switch (code) {
+                case 0xE0:
+                    state = E0;
+                    break;
+                case 0xE1:
+                    state = E1;
+                    break;
+                default:
+                    if (code < 0x80)
+                        matrix_make(code);
+                    else
+                        matrix_break(code & 0x7F);
+                    break;
+            }
+            break;
+        case E0:
+            switch (code) {
+                case 0x2A:
+                case 0xAA:
+                case 0x36:
+                case 0xB6:
+                    //ignore fake shift
+                    state = INIT;
+                    break;
+                default:
+                    if (code < 0x80)
+                        matrix_make(move_e0code(code));
+                    else
+                        matrix_break(move_e0code(code & 0x7F));
+                    state = INIT;
+                    break;
+            }
+            break;
+        case E1:
+            switch (code) {
+                case 0x1D:
+                    state = E1_1D;
+                    break;
+                case 0x9D:
+                    state = E1_9D;
+                    break;
+                default:
+                    state = INIT;
+                    break;
+            }
+            break;
+        case E1_1D:
+            switch (code) {
+                case 0x45:
+                    matrix_make(0x55);
+                    break;
+                default:
+                    state = INIT;
+                    break;
+            }
+            break;
+        case E1_9D:
+            switch (code) {
+                case 0x45:
+                    matrix_break(0x55);
+                    break;
+                default:
+                    state = INIT;
+                    break;
+            }
+            break;
+        default:
+            state = INIT;
+    }
+    matrix_scan_quantum();
+    return 1;
+}
+
+inline
+uint8_t matrix_get_row(uint8_t row)
+{
+    return matrix[row];
+}
+
+inline
+static void matrix_make(uint8_t code)
+{
+    if (!matrix_is_on(ROW(code), COL(code))) {
+        matrix[ROW(code)] |= 1<<COL(code);
+    }
+}
+
+inline
+static void matrix_break(uint8_t code)
+{
+    if (matrix_is_on(ROW(code), COL(code))) {
+        matrix[ROW(code)] &= ~(1<<COL(code));
+    }
+}
+
+void matrix_clear(void)
+{
+    for (uint8_t i=0; i < MATRIX_ROWS; i++) matrix[i] = 0x00;
+}
+
+bool matrix_is_on(uint8_t row, uint8_t col)
+{
+    return (matrix_get_row(row) & (1<<col));
+}
+
+#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))
+#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))
+#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))
+#endif
+
+void matrix_print(void)
+{
+    print_matrix_header();
+
+    for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
+        phex(row); print(": ");
+        print_matrix_row(row);
+        print("\n");
+    }
+}
+
+/*
+XT Scancodes
+============
+- http://download.microsoft.com/download/1/6/1/161ba512-40e2-4cc9-843a-923143f3456c/translate.pdf
+- https://download.microsoft.com/download/1/6/1/161ba512-40e2-4cc9-843a-923143f3456c/scancode.doc
+
+01-53: Normal codes used in original XT keyboard
+54-7F: Not used in original XT keyboard
+
+	0   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F
+    50  -   -   -   -   *   *   x   x   x   x   *   *   *   o   o   o
+    60  *   *   *   *   x   x   x   x   x   x   x   x   x   x   x   *
+    70  x   *   *   x   *   *   x   *   *   x   *   x   *   x   x   *
+
+-: codes existed in original XT keyboard
+*: E0-escaped codes converted into unused code area(internal use in TMK)
+x: Non-espcaped codes(not used in real keyboards probably, for CodeSet2-CodeSet1 translation purpose)
+o: reserved
+
+Usage in TMK:
+
+    00  (reserved) DO NOT USE
+    54  PrintScr*
+    55  Pause*
+    56  Euro2
+    57  F11
+    58  F12
+    59  Keypad =
+    5A  LGUI*
+    5B  RGUI*
+    5C  APP*
+    5D  (reserved)
+    5E  (reserved)
+    5F  (reserved)
+    60  cursor*
+    61  cursor*
+    62  cursor*
+    63  cursor*
+    64  F13
+    65  F14
+    66  F15
+    67  F16
+    68  F17
+    69  F18
+    6A  F19
+    6B  F20
+    6C  F21
+    6D  F22
+    6E  F23
+    6F  Keypad Enter*
+    70  KANA
+    71  nav*
+    72  nav*
+    73  RO
+    74  nav*
+    75  nav*
+    76  F24
+    77  nav*
+    78  nav*
+    79  HENKAN
+    7A  RCTL*
+    7B  MUHENKAN
+    7C  RALT*
+    7D  JPY
+    7E  Keypad ,
+    7F  Keypad / *
+
+*/