include: Add GPIO header file

This adds a header file to describe Fernvale's unique GPIO scheme.

Author: Sean Cross

cmd-spi.c

@@ -0,0 +1,51 @@
+#include <string.h>
+#include "bionic.h"
+#include "serial.h"
+#include "printf.h"
+#include "spi.h"
+
+#define SPI_CSEL 0
+
+int cmd_spi(int argc, char **argv)
+{
+	uint32_t recv_bytes_count;
+	uint8_t xmit_bytes[argc - 1];
+	int i;
+
+	if (argc == 1 && !_strcasecmp(argv[0], "loop")) {
+		printf("Repeatedly sending 0x9f -- id\n");
+		while(1) {
+			uint8_t out[1] = {0x9f};
+			uint8_t in[3];
+			spi_cmd_txrx(0, sizeof(out), sizeof(in), out, in);
+			printf("ID: ");
+			serial_print_hex(in, sizeof(in));
+		}
+	}
+
+	if (argc < 2) {
+		printf("Send SPI bytes out and read the response.\n");
+		printf("Usage: spi [count] [byte 1] [byte 2] ...\n");
+		printf("    Where \"count\" is the number of bytes to expect"
+			" in response.\n");
+		return 1;
+	}
+
+	recv_bytes_count = _strtoul(argv[0], NULL, 0);
+	uint8_t recv_bytes[recv_bytes_count];
+
+	for (i = 1; i < argc; i++)
+		xmit_bytes[i - 1] = _strtoul(argv[i], NULL, 0);
+
+	printf("Transmitting %d bytes and expecting a response with %d bytes:\n",
+			sizeof(xmit_bytes), sizeof(recv_bytes));
+	serial_print_hex(xmit_bytes, sizeof(xmit_bytes));
+
+	spi_cmd_txrx(SPI_CSEL, sizeof(xmit_bytes), sizeof(recv_bytes),
+			xmit_bytes, recv_bytes);
+
+	printf("Response:\n");
+	serial_print_hex(recv_bytes, sizeof(recv_bytes));
+
+	return 0;
+}