added my responsibility for the `cpm' port

[unix-history] / sys / scsi / uk.c

/* 
* Dummy driver for a device we can't identify.
* by Julian Elischer (julian@tfs.com)
*
*      $Id: uk.c,v 1.2 1993/11/25 01:37:35 wollman Exp $
*/

#include <sys/param.h>
#include "systm.h"
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <scsi/scsi_all.h>
#include <scsi/scsiconf.h>
#define NUK 16

/*
* This driver is so simple it uses all the default services
*/
struct scsi_device uk_switch =
{
   NULL,
   NULL,
   NULL,
   NULL,
   "uk",
   0,
   0, 0
};

struct uk_data {
       u_int32 flags;
       struct scsi_link *sc_link;      /* all the inter level info */
} uk_data[NUK];

#define UK_KNOWN        0x02

static u_int32 next_uk_unit = 0;

/*
* The routine called by the low level scsi routine when it discovers
* a device suitable for this driver.
*/
errval 
ukattach(sc_link)
       struct scsi_link *sc_link;
{
       u_int32 unit, i, stat;
       unsigned char *tbl;

       SC_DEBUG(sc_link, SDEV_DB2, ("ukattach: "));
       /*
        * Check we have the resources for another drive
        */
       unit = next_uk_unit++;
       if (unit >= NUK) {
               printf("Too many unknown devices..(%d > %d) reconfigure kernel\n",
                               (unit + 1), NUK);
               return (0);
       }
       /*
        * Store information needed to contact our base driver
        */
       uk_data[unit].sc_link = sc_link;
       sc_link->device = &uk_switch;
       sc_link->dev_unit = unit;

       printf("uk%d: unknown device\n", unit);
       uk_data[unit].flags = UK_KNOWN;

       return 1;               /* XXX ??? */

}

/*
*    open the device.
*/
errval 
ukopen(dev)
       dev_t dev;
{
       errval  errcode = 0;
       u_int32 unit, mode;
       struct scsi_link *sc_link;
       unit = minor(dev);

       /*
        * Check the unit is legal 
        */
       if (unit >= NUK) {
               printf("uk%d: uk %d  > %d\n", unit, unit, NUK);
               return ENXIO;
       }

       /*
        * Make sure the device has been initialised
        */
       if((uk_data[unit].flags & UK_KNOWN) == 0) {
               printf("uk%d: not set up\n", unit);
               return ENXIO;
       }
               
       /*
        * Only allow one at a time
        */
       sc_link = uk_data[unit].sc_link;
       if (sc_link->flags & SDEV_OPEN) {
               printf("uk%d: already open\n", unit);
               return ENXIO;
       }
       sc_link->flags |= SDEV_OPEN;
       SC_DEBUG(sc_link, SDEV_DB1, ("ukopen: dev=0x%x (unit %d (of %d))\n"
               ,dev, unit, NUK));
       /*
        * Catch any unit attention errors.
        */
       return 0;
}

/*
* close the device.. only called if we are the LAST
* occurence of an open device
*/
errval 
ukclose(dev)
       dev_t dev;
{
       unsigned char unit = 0, mode; /* XXX !!! XXX FIXME!!! 0??? */
       struct scsi_link *sc_link;

       sc_link = uk_data[unit].sc_link;

       SC_DEBUG(sc_link, SDEV_DB1, ("Closing device"));
       sc_link->flags &= ~SDEV_OPEN;
       return (0);
}

/*
* Perform special action on behalf of the user
* Only does generic scsi ioctls.
*/
errval 
ukioctl(dev, cmd, arg, mode)
       dev_t   dev;
       u_int32 cmd;
       caddr_t arg;
       int mode;
{
       unsigned char unit;
       struct scsi_link *sc_link;

       /*
        * Find the device that the user is talking about
        */
       unit = minor(dev);
       sc_link = uk_data[unit].sc_link;
       return(scsi_do_ioctl(sc_link,cmd,arg,mode));
}