Serial console over USB Gadget

Hi all,

Iam new to the beagle board. Since Iam not able to get an idc-10 to
DB9 serial adapter I've tried to get a serial connection using USB
gadget.

This works fine for U-Boot but I get stucked on Linux.

If U-Boot boots, on the host a ttyACM0 device appears which can be
connected to using minicom. After loading the kernel image from MMC
into RAM and booting it, minicom looses the connection to ttyACM0.
Instead a new device appears on the host called ttyACM1. But if I try
connecting to it minicom locks in "modem initialization" state...
Thus, the kernel boot is a kind of black box for me since I cant see
whats going on there (Maybe there is a kernel oops?). But it seems
that it can initialize the serial USB gadget port because of the
ttyACM1 device on the host.

Here is my kernel config / what I've done so far / kernel host output:

Beagle Board's USB serial / gadget kernel config:
  CONFIG_SERIAL_8250=y
  CONFIG_SERIAL_8250_CONSOLE=y
  CONFIG_SERIAL_8250_NR_UARTS=32
  CONFIG_SERIAL_8250_RUNTIME_UARTS=4
  CONFIG_SERIAL_8250_EXTENDED=y
  CONFIG_SERIAL_8250_MANY_PORTS=y
  CONFIG_SERIAL_8250_SHARE_IRQ=y
  CONFIG_SERIAL_8250_DETECT_IRQ=y
  CONFIG_SERIAL_8250_RSA=y

  CONFIG_SERIAL_CORE=y
  CONFIG_SERIAL_CORE_CONSOLE=y

  CONFIG_USB_SERIAL=y
  CONFIG_USB_SERIAL_CONSOLE=y
  CONFIG_USB_SERIAL_GENERIC=y

  CONFIG_USB_GADGET_MUSB_HDRC=y
  CONFIG_USB_GADGET=y

  CONFIG_USB_GADGET_VBUS_DRAW=2
  CONFIG_USB_GADGET_SELECTED=y

  CONFIG_USB_GADGET_DUALSPEED=y

What I've done so far on the U-Boot console:

  OMAP3 beagleboard.org # mmc init
  mmc1 is available
  OMAP3 beagleboard.org # fatload mmc 0:2 0x80300000 uImage
  reading uImage

  1991316 bytes read
  OMAP3 beagleboard.org # fatload mmc 0:2 0x81600000 rd-ext2.bin
  reading rd-ext2.bin

  3394477 bytes rea' - try 'help'
  OMAP3 beagleboard.org #
  OMAP3 beagleboard.org #
  OMAP3 beagleboard.org #
  OMAP3 beagleboard.org # setenv bootargs console=ttyGS0,115200n8
ramdisk_size=8192 root=/dev/ram0 rw initrd=0x81600000,8M nohz=off
rootfstype=ext2
  OMAP3 beagleboard.org # bootm 0x80300000

And last bot not least the kernel output on the host:
  redwing@euklid:~$ dmesg
  usb 2-1: USB disconnect, address 6
  usb 2-1: new high speed USB device using ehci_hcd and address 7
  usb 2-1: config 1 interface 0 altsetting 0 endpoint 0x81 has an
invalid bInterval 255, changing to 11
  usb 2-1: configuration #1 chosen from 1 choice
  cdc_acm 2-1:1.0: This device cannot do calls on its own. It is not a
modem.
  cdc_acm 2-1:1.0: ttyACM0: USB ACM device
<--- This is after booting U-Boot with working serial console on
ttyACM0.
  usb 2-1: USB disconnect, address 7
  tty_port_close_start: count = -1
  usb 2-1: new high speed USB device using ehci_hcd and address 8
  hub 2-0:1.0: unable to enumerate USB device on port 1
  tty_port_close_start: count = -1
  usb 2-1: new high speed USB device using ehci_hcd and address 9
  usb 2-1: configuration #2 chosen from 1 choice
  cdc_acm 2-1:2.0: This device cannot do calls on its own. It is not a
modem.
  cdc_acm 2-1:2.0: ttyACM1: USB ACM device
<--- This is after kernel startup

If you need additional information, please let me know.

Any help on this issue would be very appreciated.

Kind Regards,
Steve

Hi,

Have you fixed this issue ? I am facing a similar issue, any info on the topic would be useful.