Added functionality to boot BCM2835 over the USB

Makefile

@@ -0,0 +1,2 @@
+rpiboot: main.c
+	$(CC) -g -o $@ $< -lusb-1.0

main.c

@@ -0,0 +1,178 @@
+#include "libusb-1.0/libusb.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <unistd.h>
+
+int Initialize_Device(libusb_context ** ctx, libusb_device_handle ** usb_device)
+{
+	int ret = 0;
+
+	*usb_device = libusb_open_device_with_vid_pid(*ctx, 0x0a5c, 0x2763);
+	if (*usb_device == NULL)
+	{
+		return -1;
+	}
+
+	ret = libusb_claim_interface(*usb_device, 0);
+	if (ret)
+	{
+		printf("Failed to claim interface\n");
+		return ret;
+	}
+
+	return ret;
+}
+
+int ep_write(unsigned char *buf, int len, libusb_device_handle * usb_device)
+{
+	int ret =
+	    libusb_control_transfer(usb_device, LIBUSB_REQUEST_TYPE_VENDOR, 0,
+				    len & 0xffff, len >> 16, NULL, 0, 1000);
+	int a_len;
+
+	libusb_bulk_transfer(usb_device, 0x01, buf, len, &a_len, 1000);
+
+	return a_len;
+}
+
+int ep_read(unsigned char *buf, int len, libusb_device_handle * usb_device)
+{
+	int ret =
+	    libusb_control_transfer(usb_device,
+				    LIBUSB_REQUEST_TYPE_VENDOR |
+				    LIBUSB_ENDPOINT_IN, 0, len & 0xffff,
+				    len >> 16, buf, len, 1000);
+
+	return len;
+}
+
+int main(int argc, char *argv[])
+{
+	int result;
+	libusb_context *ctx;
+	libusb_device_handle *usb_device;
+	unsigned char *txbuf;
+	int size;
+	int retcode;
+	FILE *fp1, *fp2;
+	char def1[] = "usbbootcode.bin";
+	char def2[] = "msd.bin";
+	char *str1, *str2;
+	struct MESSAGE_S {
+		int length;
+		unsigned char signature[20];
+	} message;
+
+	if (argc < 3)
+	{
+		str1 = def1;
+		str2 = def2;
+	} else
+	{
+		str1 = argv[1];
+		str2 = argv[2];
+	}
+
+	fp1 = fopen(str1, "rb");
+	if (fp1 == NULL)
+	{
+		printf("Cannot open file %s\n", str1);
+		exit(-1);
+	}
+
+	fp2 = fopen(str2, "rb");
+	if (fp2 == NULL)
+	{
+		printf("Cannot open file %s\n", str2);
+		exit(-1);
+	}
+
+	int ret = libusb_init(&ctx);
+	if (ret)
+	{
+		printf("Failed to initialise libUSB\n");
+		exit(-1);
+	}
+
+	libusb_set_debug(ctx, 0);
+
+	while (1)
+	{
+		FILE *fp;
+
+		printf("Waiting for BCM2835 ...\n");
+
+		// Wait for a device to get plugged in
+		do
+		{
+			result = Initialize_Device(&ctx, &usb_device);
+			if (result)
+			{
+				sleep(1);
+			}
+
+		}
+		while (result);
+
+		{
+			struct libusb_device_descriptor desc;
+			ret =
+			    libusb_get_device_descriptor(libusb_get_device
+							 (usb_device), &desc);
+			printf("Found serial = %d: writing file %s\n",
+			       desc.iSerialNumber,
+			       desc.iSerialNumber == 0 ? str1 : str2);
+			fp = desc.iSerialNumber == 0 ? fp1 : fp2;
+		}
+
+		fseek(fp, 0, SEEK_END);
+		message.length = ftell(fp);
+		fseek(fp, 0, SEEK_SET);
+
+		txbuf = (unsigned char *)malloc(message.length);
+		if (txbuf == NULL)
+		{
+			printf("Failed to allocate memory\n");
+			exit(-1);
+		}
+
+		fread(txbuf, 1, message.length, fp);
+
+		size =
+		    ep_write((unsigned char *)&message, sizeof(message),
+			     usb_device);
+		if (size != sizeof(message))
+		{
+			printf("Failed to write correct length, returned %d\n",
+			       size);
+			exit(-1);
+		}
+
+		size = ep_write(txbuf, message.length, usb_device);
+		if (size != message.length)
+		{
+			printf("Failed to read correct length, returned %d\n",
+			       size);
+			exit(-1);
+		}
+
+		sleep(1);
+
+		size =
+		    ep_read((unsigned char *)&retcode, sizeof(retcode),
+			    usb_device);
+
+		if (retcode == 0)
+			printf("Successfull\n");
+		else
+			printf("Failed : 0x%x", retcode);
+
+		sleep(1);
+		libusb_close(usb_device);
+	}
+
+	libusb_exit(ctx);
+
+	return 0;
+}