[Keyboard] Add Whale's Split Keyboard(ver.3) (#9859)

Co-authored-by: Joel Challis <git@zvecr.com>
Co-authored-by: Ryan <fauxpark@gmail.com>
Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>

keyboards/whale/sk/v3/v3.c

@@ -0,0 +1,134 @@
+#include "v3.h"
+
+#if defined(__AVR__)
+#    include <avr/io.h>
+#    include <avr/interrupt.h>
+#endif
+
+#define ROWS_PER_HAND (MATRIX_ROWS / 2)
+#define SLAVE_MATRIX_SYNC_ADDR (0x01)
+
+typedef struct {
+    char*  buffer;
+    size_t count;
+    bool*  flag;
+} transmit_status;
+
+transmit_status irx = {}, itx = {};
+
+// Buffer for master/slave matrix scan transmit.
+// Master: receive buffer.
+// Slave: transmit buffer.
+matrix_row_t sync_matrix[ROWS_PER_HAND];
+bool         matrix_synced = false;
+
+void USART_init(uint16_t baud) {
+    cli();
+
+    // UBRR1H = (unsigned char)(baud >>8);
+    // UBRR1L = (unsigned char)(baud);
+    UBRR1 = baud;
+    // Enable U2X1 for double speed.
+    UCSR1A = (1 << U2X1);
+    // Enable RX/TX, 9N1 mode
+    UCSR1B = (1 << RXEN1) | (1 << TXEN1) | (1 << RXCIE1) | (1 << TXCIE1) | (1 << UCSZ12);
+    UCSR1C = (1 << UCSZ10) | (1 << UCSZ11);
+    sei();
+}
+
+ISR(USART1_RX_vect) {
+    // read data from reg.
+    uint8_t status   = UCSR1A;
+    uint8_t high_bit = UCSR1B;
+    uint8_t low_data = UDR1;
+    if (status & ((1 << FE1) | (1 << DOR1) | (1 << UPE1))) {
+        // Something error happen, ignore this package.
+        irx.count = 0;
+        return;
+    }
+
+    // Is it a addr? (9th bit is one/zero?)
+    if (high_bit & (1 << RXB81)) {
+        // data is addr. prepend for receive.
+        switch (low_data) {
+            case SLAVE_MATRIX_SYNC_ADDR:
+                irx.buffer = (char *)sync_matrix;
+                irx.count = sizeof(sync_matrix) * sizeof(matrix_row_t);
+                irx.flag = &matrix_synced;
+                break;
+
+            default:
+                // ignore this package.
+                irx.count = 0;
+                break;
+        }
+
+    } else if (irx.count > 0) {
+        *irx.buffer = low_data;
+        ++irx.buffer;
+        if (--irx.count == 0 && irx.flag != NULL) {
+            *irx.flag = true;
+        }
+    }
+}
+
+// TX complete
+ISR(USART1_TX_vect) {
+    // Is in transmit?
+    if (itx.count > 0) {
+        // Send data.
+        UCSR1B &= ~(1 << TXB81);
+        UDR1 = *itx.buffer;
+
+        // Move to next char.
+        ++itx.buffer;
+        if (--itx.count == 0) {
+            *itx.flag = true;
+        }
+    }
+    // TODO: read queue/register for next message.
+}
+
+// return: queue depth.
+int send_packet(uint8_t addr, char* buffer, size_t length, bool* flag) {
+    // See if we can start transmit right now.
+    if ((itx.count == 0) && (UCSR1A & (1 << UDRE1))) {
+        // Ready to write.
+        // Prepend registers.
+        itx.buffer = buffer;
+        itx.count  = length;
+        itx.flag   = flag;
+
+        // Write addr to kick start transmit.
+        UCSR1B |= (1 << TXB81);
+        UDR1 = addr;
+        // TODO: put request in queue;
+        // }else{
+    }
+
+    return 0;
+}
+
+void transport_master_init(void) { USART_init(0); }
+
+void transport_slave_init(void) { USART_init(0); }
+
+// returns false if valid data not received from slave
+bool transport_master(matrix_row_t matrix[]) {
+    if (matrix_synced) {
+        for (uint8_t i = 0; i < ROWS_PER_HAND; ++i) {
+            matrix[i] = sync_matrix[i];
+        }
+        matrix_synced = false;
+        return true;
+    }
+    return false;
+}
+
+void transport_slave(matrix_row_t matrix[]) {
+    for (uint8_t i = 0; i < ROWS_PER_HAND; ++i) {
+        sync_matrix[i] = matrix[i];
+    }
+    matrix_synced = false;
+    send_packet(SLAVE_MATRIX_SYNC_ADDR, (char*)sync_matrix, sizeof(sync_matrix) * sizeof(matrix_row_t), &matrix_synced);
+}