[PARPORT] autoloading drivers based on ieee1284 device ID changes?

From: Adam J. Richter (adam@yggdrasil.com)
Date: Mon Dec 11 2000 - 20:23:24 EST

  • Next message: Crump, Valerie: "[PARPORT] PPSETMODE and the control lines in EPP"

            I am trying to understand the issues related to making more
    general use of ieee1284 parallel port device ID information. Most
    recent parallel port printers export information about the make, model
    and feature set in this way, and I am wondering if this is also true
    for most non-printer parallel port devices (parallel port CD-ROM's,
    cameras, etc.). If so, I am wondering if it would be useful to have
    some kind of /sbin/hotplug support for this, since I understand there
    is supposed to be a way that these devices can signal that something
    has changed (hopefully this includes things like that they have been
    plugged in). That way, if you plugged in a zip disk, the module could
    be automatically loaded and other actions could also be taken, even
    things like mounting it if there is media present.

            Currently, the standard USB parallel port driver supports
    an ioctl for extracting this information, and there is a user level
    utility from Michael Fulbright at Red Hat that works with the standard
    parallel ports by manipulating IO ports directly (!), and I am
    aware of the sysctl interface, which returns ID information that
    it got at initialization time but does not redo the query.

            I guess what I would ideally like is to have the
    parallel port driver call /sbin/hotplug with DEVICE=/dev/parallel/0
    if new ieee1284 information is available, and then have
    hotplug or a program that it calls query the parallel port either
    through the existing mechanisms or, ideally, a uniform
    ioctl for downloading the ID information, and then have it
    modprobe the appropriate module based on that information.

            Such a mechanism could simply system administration
    significantly for users who are not themselves parport experts.

            Any comments on this idea would be appreciated. If it
    seems feasible, I will probably take a whack at implementing

    Adam J. Richter __ ______________ 4880 Stevens Creek Blvd, Suite 104
    adam@yggdrasil.com \ / San Jose, California 95129-1034
    +1 408 261-6630 | g g d r a s i l United States of America
    fax +1 408 261-6631 "Free Software For The Rest Of Us."

    -- 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 : Mon Dec 11 2000 - 20:28:42 EST