Re: [PARPORT] new ppdev operations

From: Tim Waugh (twaugh@redhat.com)
Date: Tue Jun 19 2001 - 13:30:40 EDT

  • Next message: Uwe Bonnes: "Re: [PARPORT] new ppdev operations"

    On Tue, Jun 19, 2001 at 07:01:21PM +0200, Uwe Bonnes wrote:

    > I don't want an emulated port, I want to allow the emulated program to
    > access the hardware. It could be done by running the emulation program with
    > root access and do the inb() and outb() direct, but that's not good for the
    > savefy of the system.

    It sounds like you want a way of restricting the I/O regions that
    /dev/port has access to, rather than using ppdev to bypass itself.
    Like:

    struct region reg = { base: 0x378, extent: 3 };
    int port = open ("/dev/port", O_RDWR);
    int ecr = open ("/dev/port", O_RDWR);
    ioctl (port, RESTRICT, &reg);
    reg.base += 0x400;
    ioctl (ecr, RESTRICT, &reg);
    drop_privs();
    ...

    I can see the use for that kind of thing.

    Tim.
    */


    -- To unsubscribe, send mail to: linux-parport-request@torque.net --
    -- with the single word "unsubscribe" in the body of the message. --

    This archive was generated by hypermail 2b29 : Tue Jun 19 2001 - 13:33:34 EDT