Support for usb-serial adapter based on cp210x

[mad_ady]

Hello all!
I was planning to use my RT-AC56U as a serial debug bridge for an Odroid board which is close by. I hooked up a USB cp210x adapter into its USB port, but it seems that support for it was not included in the kernel:

$ lsusb
Bus 003 Device 116: ID 10c4:ea60 Cygnal Integrated Products, Inc. CP210x UART Bridge / myAVR mySmartUSB light

usb 3-1: new full speed USB device using ohci_hcd and address 2
usbcore: registered new interface driver usbserial
USB Serial support registered for generic
usbcore: registered new interface driver usbserial_generic
usbserial: USB Serial Driver core
option: `0x10c4 product=0xea60' invalid for parameter `vendor'
admin@arcturus:/tmp/home/root# find  /lib/modules/2.6.36.4brcmarm/kernel/ -name
'cp210x.ko'

Since I noticed that AC56U is getting discontinued in newer releases, I'd like to ask to be pointed in the direction of the following information:
1. Are there packages with extra modules that can be downloaded directly?
2. Are there instructions on how to compile the kernel/extra modules? I plan on getting only the cp210x module and insmodding it myself, without replacing the kernel. I'm guessing the kernel only changes rarely, since it's 2.6.x

Thanks!

 

[mad_ady]

I'm going to give this a try: https://github.com/RMerl/asuswrt-merlin/wiki/Compile-Firmware-from-source-using-Ubuntu
I'll probably try to spin up a 14.04 lxc container for the job...

 

[mad_ady]

Ok, so I followed the guide above in a Ubuntu 12.04 lxc, combined with info from https://hqt.ro/how-to-compile-modules-for-asuswrt-routers/.
I went to /home/ubuntu/asuswrt-merlin.ng/release/src-rt-6.x.4708/linux/linux-2.6 and ran 'make menuconfig', selected CONFIG_USB_SERIAL_CP210X=m followed by 'make linux', 'make modules', etc.
It compiled most of the modules without dying, but for cp210x it didn't create a ko file:

root@ubuntu12:/home/ubuntu/asuswrt-merlin.ng/release/src-rt-6.x.4708/linux/linux-2.6# grep -i cp210 .config
CONFIG_USB_SERIAL_CP210X=m
root@ubuntu12:/home/ubuntu/asuswrt-merlin.ng/release/src-rt-6.x.4708/linux/linux-2.6# make drivers/usb/serial
make: Nothing to be done for `drivers/usb/serial'.
root@ubuntu12:/home/ubuntu/asuswrt-merlin.ng/release/src-rt-6.x.4708/linux/linux-2.6# ls -l drivers/usb/serial/*.ko
-rw-r--r-- 1 root root 218294 Mar 20 09:27 drivers/usb/serial/option.ko
-rw-r--r-- 1 root root 153168 Mar 20 09:27 drivers/usb/serial/usb_wwan.ko
-rw-r--r-- 1 root root 447044 Mar 20 09:27 drivers/usb/serial/usbserial.ko
root@ubuntu12:/home/ubuntu/asuswrt-merlin.ng/release/src-rt-6.x.4708/linux/linux-2.6# ls -l drivers/usb/serial/cp210x.*
-rw-r--r-- 1 root root  25671 Mar 19 17:33 drivers/usb/serial/cp210x.c
-rw-r--r-- 1 root root 129512 Mar 20 09:46 drivers/usb/serial/cp210x.o

How do I turn a .o file into a .ko?

 

[mad_ady]

... must be something wrong with my setup/environment because kernel make fails/make modules as well:

  CC [M]  drivers/usb/core/notify.o
  CC [M]  drivers/usb/core/generic.o
  CC [M]  drivers/usb/core/quirks.o
  CC [M]  drivers/usb/core/devices.o
  CC [M]  drivers/usb/core/hcd-pci.o
  CC [M]  drivers/usb/core/inode.o
  LD [M]  drivers/usb/core/usbcore.o
  CC [M]  drivers/usb/host/ehci-hcd.o
In file included from drivers/usb/host/ehci-hcd.c:1158:0:
drivers/usb/host/ehci-pci.c:438:22: fatal error: bcmutils.h: No such file or directory
compilation terminated.
make[3]: *** [drivers/usb/host/ehci-hcd.o] Error 1
make[2]: *** [drivers/usb/host] Error 2
make[1]: *** [drivers/usb] Error 2
make: *** [drivers] Error 2
root@ubuntu12:/home/ubuntu/asuswrt-merlin.ng/release/src-rt-6.x.4708/linux/linux-2.6# make kernel
  CHK     include/linux/version.h
  CHK     include/generated/utsrelease.h
make[1]: `include/generated/mach-types.h' is up to date.
  CALL    scripts/checksyscalls.sh
  CC      kernel/sched.o
  CC      kernel/fork.o
  CC      kernel/exec_domain.o
  CC      kernel/panic.o
  CC      kernel/printk.o
  CC      kernel/cpu.o
  CC      kernel/exit.o
  CC      kernel/itimer.o
  TIMEC   kernel/timeconst.h
  CC      kernel/time.o
  CC      kernel/softirq.o
kernel/softirq.c:38:22: fatal error: typedefs.h: No such file or directory
compilation terminated.
make[1]: *** [kernel/softirq.o] Error 1
make: *** [kernel] Error 2