Linux Users

Hi, The README says that USB devices will not be supported due to the kernel restricting access to the USB drivers since they're not GPL compatible. Is this going to be addressed anytime soon? Is there a workaround for this?

Unfortunately there isn't a workaround for this.  It is a pretty big problem that would require significant resources to resolve.  While there aren't plans to address this at the current time, the more feedback we here the more it will be considered.  Right now the only recommendation is to use the NI-DAQmx Base driver.  This obviously doesn't support all National Instruments USB devices, and it doesn't have all the functionality of NI-DAQmx, but for some it is sufficient.

 How about sending a fake string when you encounter a kernel version higher than 2.6.25? The fake license string would say that this is GPL compatible and thus allow access to the usbcore driver which has been locked by the EXPORT_SYMBOL_GPL flag?

Our driver is not GPL and as such we will not "fake" that it is.  Sorry, for right now USB from the NI-DAQmx driver is not a real possibility.

Using a fake string is a technical possibility, but I'm sure the NI legal team would not approve.  This also goes against the author's wishes and intent and thus I think it is best that NI respect those wishes.

As it stands right now NI-DAQmx Base provides USB support entirely from user-mode, and thus isn't affected.  Adding USB support to NI-DAQmx is more complicated since much of our existing architecture expects USB APIs in the kernel.  We are investigating the possibilities of adding that support from user-mode, or through a GPL compatible kernel component though both solutions will require a lot of work and time.

The only Linux drivers we currently have that use the USB support in the kernel is our NI-488.2 GPIB driver.  Since the nikal.c file is provided to you as source code I'm sure you could do some creative things to get the USB support back on newer kernels.

Thanks Neil and Shawn...I'll look into doing something with the nikal.c file. The newer kernels and by extension newer distros like Mandriva 2009 and Opensuse 11.0 are off limits for my application as they require some USB port access. I would imagine that I cannot use NI-VISA (Serial Port) too in the newer kernels due to this entire EXPORT_SYMBOL_GPL thingy.

Like I said the only NI products that were previously supported, but now are not on newer kernels is the GPIB-USB-HS, and GPIB-USB-B.  Everything else is done from user-mode, or simply has not been supported yet.

Shawn, is it possible then to have a generic USB-Serial dongle working on Mandriva 2009/Opensuse 11.0 through the NI-VISA drivers?

Generic (as in not NI) USB-Serial dongles should work just fine through NI-VISA.  This of course assumes that the generic USB-Serial dongle has a native Linux driver that is GPL licensed (many do).