[Keyboard] add support for ModelM USB board (#9846)

* add support for ModelM USB board

* EMI improvement: remove unnecessary toggling of MOSI pin

* address review comments

* Update keyboards/mschwingen/modelm/rules.mk

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

* Update keyboards/mschwingen/modelm/rules.mk

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

* Update keyboards/mschwingen/modelm/config.h

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

* Update keyboards/mschwingen/modelm/config.h

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

* Update keyboards/mschwingen/modelm/rules.mk

Co-authored-by: Drashna Jaelre <drashna@live.com>

* Update keyboards/mschwingen/modelm/keymaps/default/keymap.c

Co-authored-by: Drashna Jaelre <drashna@live.com>

* update printf usage

* add comment

* EMI improvement: remove unnecessary toggling of MOSI signal

* remove trailing space

* use shorter macros as suggested in review by noroadsleft, re-format table to line up columns

* Update keyboards/mschwingen/modelm/config.h

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update keyboards/mschwingen/modelm/rules.mk

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update keyboards/mschwingen/modelm/rules.mk

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update keyboards/mschwingen/modelm/rules.mk

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update keyboards/mschwingen/modelm/README.md

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update keyboards/mschwingen/modelm/README.md

Co-authored-by: Ryan <fauxpark@gmail.com>

* Apply suggestions from code review

use spi_read from core insteads of our own copy

Co-authored-by: Ryan <fauxpark@gmail.com>

* include spi_master.c to use spi_read()

* Update keyboards/mschwingen/modelm/README.md

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

* Apply suggestions from code review: correct indenting in keymap

Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

* Apply suggestions from code review

use automatic variant defines from makefile instead of defining our own

Co-authored-by: Drashna Jaelre <drashna@live.com>

* Update keyboards/mschwingen/modelm/rules.mk: use QUANTUM_LIB_SRC for uart.c

Co-authored-by: Drashna Jaelre <drashna@live.com>

Co-authored-by: Michael Schwingen <michael@schwingen.org>
Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>
Co-authored-by: Drashna Jaelre <drashna@live.com>
Co-authored-by: Ryan <fauxpark@gmail.com>

1 files changed, 117 insertions, 0 deletions

diff --git a/keyboards/mschwingen/modelm/matrix.c b/keyboards/mschwingen/modelm/matrix.c
new file mode 100644
index 000000000..ef725a61e
--- /dev/null
+++ b/keyboards/mschwingen/modelm/matrix.c
@@ -0,0 +1,117 @@
+/*
+ * Copyright 2020 Michael Schwingen
+
+ * 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 "util.h"
+#include "matrix.h"
+#include "debounce.h"
+#include "quantum.h"
+#include "spi_master.h"
+#include "print.h"
+#include "modelm.h"
+
+#define DEBUG 0
+
+#define SPI_TIMEOUT 100
+
+/* Keyboard Matrix Assignments */
+static uint16_t row_bits[MATRIX_ROWS] = {
+    0x4000, 0x8000, 0x2000, 0x1000, 0x0800, 0x0400, 0x0100, 0x0200,
+    0x0040, 0x0080, 0x0020, 0x0010, 0x0008, 0x0004, 0x0001, 0x0002};
+
+static const pin_t col_pins[MATRIX_COLS] = {D1, D4, D7, B4, F7, F6, F5, F4};
+
+static void select_col(uint8_t col) {
+    setPinOutput(col_pins[col]);
+    writePinLow(col_pins[col]);
+}
+
+static void unselect_col(uint8_t col) { setPinInputHigh(col_pins[col]); }
+
+static void unselect_cols(void) {
+    for (uint8_t x = 0; x < MATRIX_COLS; x++) {
+        setPinInputHigh(col_pins[x]);
+    }
+}
+
+static bool read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col) {
+    uint16_t row_data;
+    bool     matrix_changed = false;
+
+    // Select col and wait for col selecton to stabilize
+    select_col(current_col);
+    matrix_io_delay();
+
+    writePinLow(SR_LOAD_PIN);
+    writePinHigh(SR_LOAD_PIN);
+
+    row_data = spi_read() << 8;
+    row_data |= spi_read();
+
+#if DEBUG
+    phex(~row_data);
+    uprint(" ");
+#endif
+    // For each row...
+    for (uint8_t row_index = 0; row_index < MATRIX_ROWS; row_index++) {
+        // Store last value of row prior to reading
+        matrix_row_t last_row_value    = current_matrix[row_index];
+        matrix_row_t current_row_value = last_row_value;
+
+        // Check row pin state
+        if ((row_data & row_bits[row_index]) == 0) {
+            // Pin LO, set col bit
+            current_row_value |= (MATRIX_ROW_SHIFTER << current_col);
+        } else {
+            // Pin HI, clear col bit
+            current_row_value &= ~(MATRIX_ROW_SHIFTER << current_col);
+        }
+
+        // Determine if the matrix changed state
+        if ((last_row_value != current_row_value)) {
+            matrix_changed            = true;
+            current_matrix[row_index] = current_row_value;
+        }
+    }
+
+    // Unselect col
+    unselect_col(current_col);
+
+    return matrix_changed;
+}
+
+void matrix_init_custom(void) {
+    unselect_cols();
+    
+    // set 4MHz SPI clock
+    SPSR = 0;
+    SPCR = _BV(SPE) | _BV(MSTR) | _BV(CPOL);
+}
+
+bool matrix_scan_custom(matrix_row_t current_matrix[]) {
+    bool changed = false;
+
+#if DEBUG
+    uprint("\r\nScan: ");
+#endif
+    // Set col, read rows
+    for (uint8_t current_col = 0; current_col < MATRIX_COLS; current_col++) {
+        changed |= read_rows_on_col(current_matrix, current_col);
+    }
+    update_layer_leds();
+    return changed;
+}