Am Dienstag, den 05.10.2010, 19:24 +0200 schrieb Uwe Bonnes: > >>>>> "Thomas" == Thomas Klose <[email protected]> writes: > > Thomas> Am Dienstag, den 05.10.2010, 18:14 +0200 schrieb Uwe Bonnes: > >> >>>>> "Uwe" == Uwe Bonnes <[email protected]> > >> writes: > >> > >> >>>>> "Thomas" == Thomas Klose <[email protected]> writes: > >> > Uwe> In your situation, however it is wrong. Ideas how to handle that > Uwe> situation are welcome. > >> To clarify the situation. Device gets plugged, ftdi_sio gets > >> loaded. First libftdi open calls libusb_detach_kernel_driver() and > >> gets access. Second libftdi open calls calls again > >> libusb_detach_kernel_driver() and gets access too. > > Thomas> To be honest, I think tampering with the system's configuration > Thomas> by detaching device drivers seems a little drastic to me, > Thomas> especially if it is default behavior. > > Thomas> sio gets loaded because it is the driver for devices with a > Thomas> certain vendor and product id. If this is not wanted for a > Thomas> device, it should be set to another id. > > But here you get in a chicken/egg problem. VID 0x403/PID 0x6001|6010 are the > default FTDI VID/PID and ftdi_sio needs to be loaded for many devices on the > market. However 0x403/PID 0x6001|6010 is also the default VID/PID of new > FTDI devices you want to use for something else. So how do you program > these to a diffent VID/PID? > > With the ability to specify VID/PID/Product description and Serial string in > libftdi, you also minimize the changes to "catch" a wrong device. > Setting an alternative PID is not a problem at all. You can download a tool from FTDI's website to do it. In our experience there is also no problem to get a reserved PID or even a PID range for a new kind of a device.
If the producers of this devices don't do this, this is very bad and I acknowledge that for some applications it is necessary than to automatically detach the sio module for a device with a certain description string. But this very dirty solution should not define the default behavior of libftdi, should it? -- libftdi - see http://www.intra2net.com/en/developer/libftdi for details. To unsubscribe send a mail to [email protected]
