1 files changed, 124 insertions, 0 deletions
diff --git a/src/split.c b/src/split.c
new file mode 100644
index 0000000..ac07868
--- /dev/null
+++ b/src/split.c
@@ -0,0 +1,124 @@
+#include "split.h"
+#include "util.h"
+#include "matrix.h"
+
+#include "hardware/gpio.h"
+#include "hardware/regs/intctrl.h"
+#include "hardware/uart.h"
+#include "hardware/timer.h"
+#include "bsp/board.h"
+#include "tusb.h"
+
+#define UART_TX_PIN 0
+#define UART_RX_PIN 1
+
+enum {
+	CMD_SCAN_MATRIX_REQ = 0x80,
+	CMD_SCAN_MATRIX_RESP,
+	CMD_STDIO_PUTS
+};
+
+enum { SLAVE, MASTER };
+enum { LEFT, RIGHT };
+
+static void split_rx_cmd(uint8_t cmd);
+static void split_rx(void);
+
+static bool scan_pending = false;
+
+void
+split_rx_cmd(uint8_t cmd)
+{
+	char buf[64];
+	uint8_t c;
+	uint len;
+
+	switch (cmd) {
+	case CMD_SCAN_MATRIX_REQ:
+		if (SPLIT_ROLE != SLAVE);
+			break;
+		scan_pending = true;
+		return;
+	case CMD_SCAN_MATRIX_RESP:
+		if (SPLIT_ROLE != MASTER);
+			break;
+		scan_pending = false;
+		return;
+	case CMD_STDIO_PUTS:
+		if (SPLIT_ROLE != MASTER);
+			break;
+		len = 0;
+		while (uart_is_readable(uart0) && (c = uart_getc(uart0))) {
+			if (len == ARRLEN(buf)) {
+				tud_cdc_write(buf, len);
+				buf[0] = c;
+				len = 1;
+			} else {
+				buf[len++] = c;
+			}
+		}
+		if (len) {
+			tud_cdc_write(buf, len);
+			tud_cdc_write_flush();
+		}
+		return;
+	}
+
+	WARN("Unexpected uart cmd: %i", cmd);
+}
+
+void
+split_rx(void)
+{
+	while (uart_is_readable(uart0))
+		split_rx_cmd(uart_getc(uart0));
+}
+
+void
+split_init(void)
+{
+	uart_init(uart0, 2400);
+
+	gpio_set_function(UART_TX_PIN, GPIO_FUNC_UART);
+	gpio_set_function(UART_RX_PIN, GPIO_FUNC_UART);
+
+	uart_set_baudrate(uart0, 115200);
+
+	uart_set_hw_flow(uart0, false, false);
+
+	uart_set_format(uart0, 8, 1, UART_PARITY_NONE);
+
+	uart_set_fifo_enabled(uart0, true);
+
+	irq_set_exclusive_handler(UART0_IRQ, split_rx);
+	irq_set_enabled(UART0_IRQ, true);
+
+	uart_set_irq_enables(uart0, true, false);
+}
+
+void
+split_task(void)
+{
+	uint32_t start_ms;
+
+	if (SPLIT_ROLE == SLAVE) {
+		if (scan_pending) {
+			scan_matrix();
+			uart_putc_raw(uart0, CMD_SCAN_MATRIX_RESP);
+			scan_pending = false;
+		}
+		uart_putc_raw(uart0, CMD_STDIO_PUTS);
+		uart_putc_raw(uart0, '.');
+		uart_putc_raw(uart0, 0);
+	} else if (SPLIT_ROLE == MASTER) {
+		scan_pending = true;
+		uart_putc_raw(uart0, CMD_SCAN_MATRIX_REQ);
+		scan_matrix(); /* scan our side in parallel */
+		start_ms = board_millis();
+		while (scan_pending && board_millis() < start_ms + 50)
+			tud_task();
+		if (scan_pending) WARN("Slave matrix scan timeout");
+		else DEBUG("Slave matrix scan success");
+		scan_pending = false;
+	}
+}