Import old unfinished FT232R bit-banging code for sim sniffing

This code never really worked due to large sample clock jitter, lost
USB messages and the lack of CLK sniffing ability

ft232r/soft_uart.h

@@ -0,0 +1,35 @@
+#ifndef _SOFT_UART_H
+#define _SOFT_UART_H
+
+enum suart_state {
+	WAIT_RESET,
+	IN_RESET,
+	WAIT_START_FALLEDGE,
+	WAIT_START_ETU07,
+	RX_BITS,
+	POST_RX_WAIT_HIGH,
+};
+
+enum suart_convention {
+	DIRECT_CONVENTION,
+	INVERSE_CONVENTION,
+};
+
+struct suart_data {
+	uint32_t samplerate;	/* samples per second input rate */
+	uint32_t recip_etu;	/* 1/etu */
+	uint8_t num_bits;
+
+	enum suart_state state;
+	enum suart_convention convention;
+
+	uint32_t sample_after_sbit;
+	uint8_t bits_pending;
+
+	uint8_t rx_char;
+};
+
+int suart_process_sample_bit(struct suart_data *suart, uint8_t clk_bit, uint8_t rst_bit, uint8_t sample_bit);
+void suart_init(struct suart_data *su);
+
+#endif