>> Signed-off-by: Hannes Weisbach <hannes_weisb...@gmx.net> >> --- >> Granted, for normal parport drivers this is usually not an issue, >> because the device does not go away. However, I am currently writing a >> Linux device driver for a USB to parallel port converter [0] and >> therefore need proper detaching. Additionally, the wrong ref count >> keeps me from simply rmmod my driver and insmod a new version while >> developing and testing. > > Really? We already have a usb to parallel port driver in the kernel > tree that seems to work just fine.
> It's been there since the 2.3 kernel > days, so either it has the same problem, or your driver is doing > something odd. Do you mean the USB Printer class driver for pseudo parallel port adapters? They don't use the char/lp.c printer driver. (Or I didn't see it). I'm writing a driver for USB2LPT [0], which gives you a real /dev/parportN-device in user space, with which you can do all the bit-twiddling like with a real parallel port. Or do you mean USS720 (misc/uss720.c) and MOS7715 (serial/mos7720.c) drivers. They are doing what I am doing: translating whatever the user does on a /dev/parportN-node and sending device-specific commands over USB. When they do parport_announce_port(), lp.c should also be initialized and they should have the same problem. On second thought, my patch might not be optimal. lp.c stores instance-structs in an array of size 8. So after 8 re-plugs, lp.c will not instantiate any more printer devices. I think I better go all the way and replace that array with a list, to have a proper solution. [0] http://www-user.tu-chemnitz.de/~heha/bastelecke/Rund%20um%20den%20PC/USB2LPT/index.html.en-- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
