1 files changed, 64 insertions, 0 deletions
diff --git a/usb-dfu-experiment/sam3u_chipid_usbserial.c b/usb-dfu-experiment/sam3u_chipid_usbserial.c
new file mode 100644
index 0000000..c8d0e70
--- /dev/null
+++ b/usb-dfu-experiment/sam3u_chipid_usbserial.c
@@ -0,0 +1,64 @@
+#include <board.h>
+
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#include <memories/flash/flashd.h>
+
+#include <usb/common/core/USBStringDescriptor.h>
+
+#include <usb/device/dfu/dfu.h>
+
+/* 128bit binary serial, equals 16 bytes -> 32 hex digits */
+static uint8_t usb_serial_string[USBStringDescriptor_LENGTH(32)];
+
+/* convert from 7-bit ASCII to USB string */
+static int to_usb_string(char *out, int out_len, const char *in)
+{
+	int in_len = strlen(in);
+	int num_out = USBStringDescriptor_LENGTH(in_len);
+	int i;
+	char *cur = out;
+
+	if (num_out > out_len || num_out >= 255 || num_out < 0)
+		return -EINVAL;
+
+	*cur++ = num_out;
+	*cur++ = USBGenericDescriptor_STRING;
+
+	for (i = 0; i < in_len; i++) {
+		*cur++ = in[i];
+		*cur++ = 0;
+	}
+
+	return cur - out;
+}
+
+static int chip_uid_to_usbstring(void)
+{
+	unsigned long uniqueID[4];
+	int rc;
+
+	FLASHD_Initialize(0);
+	rc = FLASHD_ReadUniqueID(&uniqueID);
+	if (rc != 0)
+		return -EIO;
+
+	/* we skip the step to transform the unique-id into hex before
+	 * converting it into a USB string, as it seems to consist of ASCII
+	 * characters instead of a true 128 bit binary unique identifier */
+	rc = to_usb_string(usb_serial_string, sizeof(usb_serial_string), (char *) uniqueID);
+	if (rc > 0)
+		return 0;
+
+	return rc;
+}
+
+int chipid_to_usbserial(void)
+{
+	chip_uid_to_usbstring();
+	set_usb_serial_str(usb_serial_string);
+}