This dongle is also known as the Nordic PCA10059.
new full-speed USB device number 32 using xhci_hcd New USB device found, idVendor=1915, idProduct=521f, bcdDevice= 1.00 New USB device strings: Mfr=1, Product=2, SerialNumber=3 Product: Open DFU Bootloader Manufacturer: Nordic Semiconductor SerialNumber: C04D05ED8331 ttyACM2: USB ACM device