I'm using Android/Linux and trying to interface modem module.
The interface of the module is USB and it supports CDC-ACM(Modem Function)and CDC-WDM(Device Management Function)

I can see only /dev/ttyACM0 device node but /dev/cdc-wdm is not created.

Android ICS, Kernel : 3.0.31

Kernel config
kernel/arch/arm/configs/bp50_defconfig
CONFIG_USB_ACM=y
CONFIG_USB_WDM=y

cdc-wdm was complied.
kernel/drivers/usb/class/cdc-wdm.o
kernel/drivers/usb/class/.cdc-wdm.o.cmd
kernel/drivers/usb/class/cdc-wdm.c

from /dev
crwxrwxrwx radio radio 166, 0 2013-03-22 16:09 ttyACM0
but cdc-wdm0 is not seen.

From kernel log
<7>[ 7.179931] usb 1-1.3: default language 0x0409
<7>[ 7.186126] usb 1-1.3: udev 3, busnum 1, minor = 2
<6>[ 7.186126] usb 1-1.3: New USB device found, idVendor=0482, idProduct=0232
<6>[ 7.199127] usb 1-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=0
<6>[ 7.207275] usb 1-1.3: Product: KCMP
<6>[ 7.211334] usb 1-1.3: Manufacturer: KYOCERA CORPORATION
<7>[ 7.218200] usb 1-1.3: usb_probe_device
<7>[ 7.222625] usb 1-1.3: configuration #1 chosen from 1 choice
<7>[ 7.229827] usb 1-1.3: adding 1-1.3:1.0 (config #1, interface 0)
<7>[ 7.238281] usbserial_generic 1-1.3:1.0: usb_probe_interface
<7>[ 7.244689] usbserial_generic 1-1.3:1.0: usb_probe_interface - got id
<7>[ 7.252441] usb 1-1.3: adding 1-1.3:1.1 (config #1, interface 1)
<7>[ 7.259765] cdc_acm 1-1.3:1.1: usb_probe_interface
<7>[ 7.259765] cdc_acm 1-1.3:1.1: usb_probe_interface - got id
<6>[ 7.271697] twl6030_bci twl6030_bci: Battery Voltage at Bootup is 0 mV
<6>[ 7.279174] cdc_acm 1-1.3:1.1: ttyACM0: USB ACM device
<7>[ 7.285980] usb 1-1.3: adding 1-1.3:1.2 (config #1, interface 2)
<7>[ 7.293457] usb 1-1.3: adding 1-1.3:1.3 (config #1, interface 3)
<7>[ 7.301422] cdc_wdm 1-1.3:1.3: usb_probe_interface
<7>[ 7.306823] cdc_wdm 1-1.3:1.3: usb_probe_interface - got id
<7>[ 7.313323] cdc_wdm 1-1.3:1.3: looking for a minor, starting at 176
<6>[ 7.320587] cdc_wdm 1-1.3:1.3: cdc-wdm0: USB WDM device // ==>> Device was binded
<7>[ 7.327087] usb 1-1.3: adding 1-1.3:1.4 (config #1, interface 4)
<6>[ 7.335723] OMAP Watchdog Timer Rev 0x00: initial timeout 30 sec
<6>[ 7.343322] Bluetooth: HCI UART driver ver 2.2
<7>[ 7.348663] usbserial_generic 1-1.3:1.4: usb_probe_interface
<7>[ 7.355041] usbserial_generic 1-1.3:1.4: usb_probe_interface - got id
<6>[ 7.362274] Bluetooth: HCI H4 protocol initialized
<6>[ 7.367950] cpuidle: using governor ladder
<7>[ 7.368377] drivers/usb/core/inode.c: creating file '003'

I guess kernel should send uevent to udev and udev genterate /dev/cdc-wdm device node.

system/core/rootdir/ueventd.rc
/dev/ttyACM0 0777 radio radio
/dev/cdc-wdm0 0777 radio radio

}

device/ti/bluebird/init.bluebird.rc
chmod 0666 /dev/ttyACM0
chown radio radio /dev/ttyACM0
chmod 0666 /dev/cdc-wdm0
chown radio radio /dev/cdc-wdm0


I do not know how to check uevent was generated and whether udev worked properly.

Is there any one who can tell me what I need to check and what I should do more for this ?


Please tell me if there is anything missed .

I found cdc-wdm0 is created under /sys/class/usb and also uevent.

root@android:/sys/class/usb/cdc-wdm0 # ll
ll
-r--r--r-- root root 4096 2013-04-03 02:44 dev
lrwxrwxrwx root root 2013-04-03 02:44 device -> ../../../1-1.3:1.3
drwxr-xr-x root root 2013-04-03 02:35 power
lrwxrwxrwx root root 2013-04-03 02:44 subsystem -> ../../../../../../../../../../../class/usb
-rw-r--r-- root root 4096 2013-04-03 02:35 uevent

root@android:/sys/class/usb/cdc-wdm0 # cat uevent
cat uevent
MAJOR=180
MINOR=176
DEVNAME=cdc-wdm0

I wonder whether uevent was properly delivered to udev and ueventd was worked properly.

I can't see any udev logs at all.

Please comment anything regarding this problem.

I have the same issue when enable MBIM module on android? Could you give me any comments?

Same exact problem here!
Did you solve the problem? If yes, how?

Thank you.

handle_generic_device_event @./system/core/init/devices.c
static void handle_generic_device_event(struct uevent *uevent)
{
//…
name = parse_device_name(uevent, 64);
if (!name)
return;

if (!strncmp(uevent->subsystem, "usb", 3)) {
if (!strcmp(uevent->subsystem, "usb")||!strcmp(uevent->subsystem, "usbmisc")) {
//…
}

Great, it worked!
Thank you!