On Fri, 26 Jun 2020 14:47:13 +0200 Hans Petter Selasky <h...@selasky.org> wrote:
> Hi, > > On 2020-06-26 13:51, Jan Behrens wrote: > > I made the discovery that running the library as root works just fine! > > The libusb_reset_device() function needs root permissions! This is > expected. There are specific checks in the kernel for this. I might have misunderstood your earlier post: On Thu, 25 Jun 2020 20:16:14 +0200 Hans Petter Selasky <h...@selasky.org> wrote: > Unless the device requires it, libusb_reset_device(), will only > re-enumerate the device. Beware that this only is allowed if you are > running the application as root. Else libusb_reset_device() will be a > no-operation. > > --HPS Does this mean that depending on the device, it will either be a no-operation or a re-enumeration, and in the latter case, root privileges are required, otherwise not? Or did you mean that if you are non-root, it will/should always be a no-operation? What I don't understand is that the Lime Suite SoapySDR module seems to work fine on Linux and other operating systems but makes trouble with FreeBSD. Is it a FreeBSD specific thing that libusb_reset_device() fails if called as non-root? > Can you run this app as root, and then change to non-root after > libusb_reset_device() has been executed? > > --HPS It's not really practical. I'd have to patch every program using the module. But maybe libusb_reset_device() isn't necessary to call? I could give recommendation to the Lime Suite developers to remove the libusb_reset_device() call on FreeBSD systems if it is not neccessary. However, I would like to understand why it is called and what's its usual purpose, and if there are side effects when removing the call, or whether the call should/could be replaced by a different call that "only" requires device privileges. Also: Why does this work on Linux but fails on FreeBSD? Is the API differently defined? Sorry for my confusion, I'm really not experienced with USB programming. Regards, Jan Behrens _______________________________________________ freebsd-usb@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-usb To unsubscribe, send any mail to "freebsd-usb-unsubscr...@freebsd.org"
