1 files changed, 95 insertions, 0 deletions
diff --git a/keyboards/switchplate/southpaw_65/matrix.c b/keyboards/switchplate/southpaw_65/matrix.c
new file mode 100644
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+++ b/keyboards/switchplate/southpaw_65/matrix.c
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+/* Copyright 2019
+ *
+ * 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 <avr/io.h>
+#include <string.h>
+#include "matrix.h"
+#include "pca9555.h"
+#include "quantum.h"
+
+#include "debug.h"
+
+// PCA9555 slave addresses
+#define IC1 0x20
+#define IC2 0x21
+
+//_____Utility funcs___________________________________________________________
+
+static void init_pins(void) {
+    // init all rows - IC1 port0 input
+    pca9555_set_config(IC1, PCA9555_PORT0, ALL_INPUT);  // same as initial state
+
+    // init all cols high - IC2 all input
+    pca9555_set_config(IC1, PCA9555_PORT1, ALL_INPUT);  // same as initial state
+    pca9555_set_config(IC2, PCA9555_PORT0, ALL_INPUT);  // same as initial state
+    pca9555_set_config(IC2, PCA9555_PORT1, ALL_INPUT);  // same as initial state
+    
+    pca9555_set_output(IC1, PCA9555_PORT0, ALL_LOW);
+}
+
+static void select_row(uint8_t row) {
+    // For the Southpaw Ext 65% pins 1-6 are used for the rows
+    uint8_t pin  = row;
+    uint8_t mask = 2 << pin;
+
+    pca9555_set_config(IC1, PCA9555_PORT0, ALL_INPUT & (~mask));
+}
+
+static uint32_t read_cols(void) {
+    //Read column inputs. Pins 13-31 are used. Split across both ICs but they are sequential
+    uint32_t state_1 = pca9555_readPins(IC1, PCA9555_PORT1);
+    uint32_t state_2 = pca9555_readPins(IC2, PCA9555_PORT0);
+    uint32_t state_3 = pca9555_readPins(IC2, PCA9555_PORT1);
+
+    uint32_t state = (((state_3 & 0b01111111) << 12) | (state_2 << 4) | ((state_1 & 0b11110000) >> 4));
+    return ~state;
+}
+
+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 selection to stabilize
+    select_row(current_row);
+    // Skip the wait_us(30); as i2c is slow enough to debounce the io changes
+
+    current_matrix[current_row] = read_cols();
+
+    // No need to Unselect row as the next `select_row` will blank everything
+
+    return (last_row_value != current_matrix[current_row]);
+}
+
+//_____CUSTOM MATRIX IMPLEMENTATION____________________________________________________
+
+void matrix_init_custom(void) {
+    pca9555_init(IC1);
+    pca9555_init(IC2);
+
+    init_pins();
+}
+
+bool matrix_scan_custom(matrix_row_t current_matrix[]) {
+    bool changed = false;
+    for (uint8_t current_row = 0; current_row < MATRIX_ROWS; current_row++) {
+        changed |= read_cols_on_row(current_matrix, current_row);
+    }
+    return changed;
+}