Hello, I am trying to figure out how to get a g_serial device running on the Acme Acqua board built around the Atmel SAMA5D3. I am using an unmodified 4.5 kernel with a configuration and a dts file provided by Acme (originally for kernel version 4.4.5, but the problems I encountered appear to be the same on earlier versions). I have enabled gadget support and the serial gadget device using menuconfig, alongside CONFIG_USB_ATMEL_USBA. But it doesn't work. I have enabled the verbose debugging options and captured the following messages: atmel_usba_udc 500000.gadget: MMIO registers at 0xf8030000 mapped at d08d8000 atmel_usba_udc 500000.gadget: FIFO at 0x00500000 mapped at d2200000 userial_init: registered 4 ttyGS* devices udc 500000.gadget: registering UDC driver [g_serial] g_serial gadget: adding 'acm'/cfb53a00 to config 'CDC ACM config'/c0775adc g_serial gadget: acm ttyGS0: dual speed IN/ep1 OUT/ep2 NOTIFY/ep3 g_serial gadget: Gadget Serial v2.4 g_serial gadget: g_serial ready ... -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html