arch/all-unix/devs/unixio/deviceutil.c

   1 static int unixio_Open(struct unixioDev *, struct IORequest *ioreq, IPTR unit, ULONG flags)
   2 {
   3     struct UnitData *data;
   4
   5     D(bug("unixio.device: Open unit %s\n",unit));
   6
   7     if (ioreq->io_Message.mn_Length < sizeof(struct IOStdReq))
   8     {
   9         D(bug("unixio.device/open: IORequest structure passed to OpenDevice is too small!\n"));
  10
  11         ioreq->io_Error = IOERR_OPENFAIL;
  12         return FALSE;
  13     }
  14
  15     ioreq->io_Message.mn_Node.ln_Type = NT_REPLYMSG;
  16
  17     /*
  18      * In the list of available units look for the one with the same
  19      UnitNumber as the given one  */
  20   if (0 == ioreq->io_Error)
  21   {
  22     PU = findUnit(ParallelDevice, unitnum);
  23
  24     /* If there is no such unit, yet, then create it */
  25     if (NULL == PU)
  26     {
  27       D(bug("Creating Unit %d\n",unitnum));
  28       PU = AllocMem(sizeof(struct ParallelUnit), MEMF_CLEAR|MEMF_PUBLIC);
  29       if (NULL != PU)
  30       {
  31         PU->pu_OpenerCount      = 1;
  32         PU->pu_UnitNum          = unitnum;
  33         PU->pu_Flags            = ioreq->io_Flags;
  34
  35         /*
  36         ** Initialize the message ports
  37         */
  38         NEWLIST(&PU->pu_QReadCommandPort.mp_MsgList);
  39         PU->pu_QReadCommandPort.mp_Node.ln_Type = NT_MSGPORT;
  40
  41         NEWLIST(&PU->pu_QWriteCommandPort.mp_MsgList);
  42         PU->pu_QWriteCommandPort.mp_Node.ln_Type= NT_MSGPORT;
  43
  44         InitSemaphore(&PU->pu_Lock);
  45         /* do further initilization here. Like getting the ParallelUnit Object etc. */
  46
  47         PU->pu_Unit  = HIDD_Parallel_NewUnit(ParallelDevice->ParallelObject, unitnum);
  48         if (NULL != PU->pu_Unit)
  49         {
  50           HIDD_ParallelUnit_Init(PU->pu_Unit, RBF_InterruptHandler, NULL, WBE_InterruptHandler, NULL);
  51           ioreq->io_Device = (struct Device *)ParallelDevice;
  52           ioreq->io_Unit   = (struct Unit *)PU;
  53
  54           /*
  55           ** put it in the list of open units
  56           */
  57           AddHead(&ParallelDevice->UnitList, (struct Node *)PU);
  58
  59           ioreq->io_Error  = 0;
  60
  61           return TRUE;
  62         }
  63
  64         D(bug("ParallelUnit could not be created!\n"));
  65
  66         FreeMem(PU, sizeof(struct ParallelUnit));
  67
  68         ioreq->io_Error = ParErr_DevBusy;
  69       }
  70     }
  71     else
  72     {
  73       /* the unit does already exist. */
  74       /*
  75       ** Check whether one more opener to this unit is tolerated
  76       */
  77       if (0 != (PU->pu_Flags & PARF_SHARED))
  78       {
  79         /*
  80         ** This unit is in shared mode and one more opener
  81         ** won't hurt.
  82         */
  83         ioreq->io_Device = (struct Device *)ParallelDevice;
  84         ioreq->io_Unit   = (struct Unit *)PU;
  85         ioreq->io_Error  = 0;
  86
  87         PU->pu_OpenerCount++;
  88       }
  89       else
  90       {
  91         /*
  92         ** I don't allow another opener
  93         */
  94         ioreq->io_Error = ParErr_DevBusy;
  95       }
  96     }
  97   }
  98
  99   return TRUE;
 100 }
 101
 102
 103 /****************************************************************************************/
 104
 105 static int GM_UNIQUENAME(Close)
 106 (
 107     LIBBASETYPEPTR ParallelDevice,
 108     struct IORequest *ioreq
 109 )
 110 {
 111   struct ParallelUnit * PU = (struct ParallelUnit *)ioreq->io_Unit;
 112
 113   /*
 114   ** Check whether I am the last opener to this unit
 115   */
 116   if (1 == PU->pu_OpenerCount)
 117   {
 118     /*
 119     ** I was the last opener. So let's get rid of it.
 120     */
 121     /*
 122     ** Remove the unit from the list
 123     */
 124     Remove((struct Node *)&PU->pu_Node);
 125
 126     HIDD_Parallel_DisposeUnit(ParallelDevice->ParallelObject, PU->pu_Unit);
 127
 128     FreeMem(PU, sizeof(struct ParallelUnit));
 129
 130   }
 131   else
 132   {
 133     /*
 134     ** There are still openers. Decrease the counter.
 135     */
 136     PU->pu_OpenerCount--;
 137   }
 138
 139   return TRUE;
 140 }
 141
 142 /****************************************************************************************/