Recent changes to 25: Raspberry Pi 3 B+ and NI USB-GPIB-HS communication using linux gpib

#25 Raspberry Pi 3 B+ and NI USB-GPIB-HS communication using linux gpib

2019-06-21T21:05:32.721000Z

The null dereference is happening in the kernel, gdb isn't going to be able to see anything after the call to ioctl(). The ioctl call will result in the ibioctl function getting called in the kernel module, that is why I suggested adding some printk in osfuncs.c. Judging by your gdb output, you should see ibioctl() getting called with cmd parameter set to IBMUTEX, which should then result in a call to mutex_ioctl().

#25 Raspberry Pi 3 B+ and NI USB-GPIB-HS communication using linux gpib

2019-06-21T16:02:09.929000Z

Ok, so I was trying to debug using gdb and it seems that device (gpib-usb-hs) cannot be configured propoerly. See attached photo for the backtrace.

I am also using linux-gpib 4.2.0 on a raspberry pi using a 4.19.50-v7+ kernel (the raspberrypi-kernel and raspberrypi-kernel-headers packages in Raspberrian).

By the way, I have also tried communicating with the gpib-usb-hs on Windows with NI VISA tool and is working fine (so this is not a hardware fault!!).

#25 Raspberry Pi 3 B+ and NI USB-GPIB-HS communication using linux gpib

2019-06-14T20:28:33.978000Z

Ok, I just built and tried linux-gpib 4.2.0 on a raspberry pi using a 4.19.42-v7+ kernel (the raspberrypi-kernel and raspberrypi-kernel-headers packages in Raspberrian). I was unable to reproduce your problem, gpib_config worked fine with a gpib-usb-hs+.

Can you zero in on where the NULL dereference is happening in the ibioctl function? You could add some printk to debug ibioctl() in drivers/gpib/sys/osfuncs.c.

#25 Raspberry Pi 3 B+ and NI USB-GPIB-HS communication using linux gpib

2019-06-14T10:14:33.153000Z

Yes, in fact I'm getting an internal error Oops: 17 [#1] SMP ARM

See attachements for full output of dmesg after the segmentation fault.

Thanks,

#25 Raspberry Pi 3 B+ and NI USB-GPIB-HS communication using linux gpib

2019-06-13T10:44:35.846000Z

Hi Frank,

Thanks for getting back.

So I have managed to get the linux-gpib installed and recognize my device.

However, I am now getting the error of Segmentation fault when promtping the command gpib_config.

Any thoughts why this is caused?

#25 Raspberry Pi 3 B+ and NI USB-GPIB-HS communication using linux gpib

2019-06-10T20:17:13.535000Z

You'll have to provide more detailed information about what errors you are encountering. One thing is, I believe the udev scripts in your version fail to run gpib_config unless the ni_usb_gpib kernel module is already loaded when the gpib adapter is plugged in.

Raspberry Pi 3 B+ and NI USB-GPIB-HS communication using linux gpib

2019-06-07T16:05:35.579000Z

Hi,

I am trying to get a communication between a Raspberry Pi 3 B+ and NI USB-GPIB-HS.

I have downloaded the latest linux gpib 4.2.0 and my pi is running on the latest 4.19.46-v7+ kernel. I have been through tons of tutorial but none could get my communication working properly, as it turns out that they might have been out-dated by now.

Do you have any specific procedure I can follow in order to make this working?

Thanks,

GT18