gadget serial hangs kernel after open(dev/ttyGS0)

[chandraevolute]

Hi 

I am facing a strange issue 

Below is my sample code 

iSerialFD = open("/dev/ttyGS0",O_RDWR | O_NONBLOCK);

if(iSerialFD < 0)
{
   printf("\n Error! in Opening ttyGS0\n");
   return 0;

}
else
   printf("\n ttyGS0 Opened Successfully\n");
   printf("I am here\n");

After performing open it is printing the ttyGS0 Opened successfully but it is not going after that statement. Kernel hangs up there. 

Another strange issue is I can perform open read write of the same gadget serial port if I compile the serial program as a single C file. But when I link all the output files to single executable I am facing this problem. 

Attached is the code.

Original Attachment has been moved to: SerialTesting.c.zip

[Bio_TICFSL]

Hi chandra

Looks like kernel hangs because USB gadget is not enable correctly, please make sure that your USBgadget is enable on your kernel config on Device Drivers --> USB support --> USB Gadget support --> [*] Function Filesystem (Function FS).

After reboot 

# mount -t configfs none /sys/kernel/config

# cd /sys/kernel/config/

# ls usb_gadget

# cd usb_gadget

If USB Gadget configfs support is enabled we’ll have a usb_gadget subdirectory present. then try to make your tests again.

hope this helps