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DEV_MODULE(9)         DragonFly Kernel Developer's Manual        DEV_MODULE(9)

NAME
     DEV_MODULE -- device driver module declaration macro

SYNOPSIS
     #include <sys/module.h>
     #include <sys/conf.h>

     DEV_MODULE(name, modeventhand_t evh, void *arg);

DESCRIPTION
     The DEV_MODULE() macro declares a device driver kernel module.  It fills
     in a moduledata_t structure and then calls DECLARE_MODULE() with the cor-
     rect args, where name is the name of the module and evh (with its argu-
     ment arg) is the event handler for the module (refer to DECLARE_MODULE(9)
     for more information).  The event handler is supposed to create the
     device with make_dev() on load and to destroy it when it is unloaded
     using destroy_dev().

EXAMPLES
     #include <sys/module.h>
     #include <sys/conf.h>

     static struct dev_ops foo_ops = { ... };

     static cdev_t sdev;

     static int
     foo_load(module_t mod, int cmd, void *arg)
     {
         int err = 0;

         dev_ops_add(&foo_ops, ...);

         switch (cmd) {
         case MOD_LOAD:
             sdev = make_dev(&foo_ops, 0, UID_ROOT, GID_WHEEL, 0600, "foo");

             /* We must obtain a reference to sdev, so we can destroy it later */
             reference_dev(sdev);
             break;          /* Success*/

         case MOD_UNLOAD:
         case MOD_SHUTDOWN:
             destroy_dev(sdev);

             /* The same mask and match must be specified, as in dev_ops_add() */
             dev_ops_remove(&foo_ops, ...);
             break;          /* Success*/

         default:
             err = EINVAL;
             break;
         }

         return(err);
     }

     DEV_MODULE(foo, foo_load, NULL);

SEE ALSO
     DECLARE_MODULE(9), destroy_dev(9), make_dev(9), module(9)

AUTHORS
     This manual page was written by Alexander Langer <alex@FreeBSD.org>.

DragonFly 3.5                  February 10, 2009                 DragonFly 3.5