lincan/src/open_rtl.c

   1 /* open.c
   2  * Linux CAN-bus device driver.
   3  * Written by Arnaud Westenberg email:arnaud@wanadoo.nl
   4  * Rewritten for new CAN queues by Pavel Pisa - OCERA team member
   5  * email:pisa@cmp.felk.cvut.cz
   6  * This software is released under the GPL-License.
   7  * Version lincan-0.2  9 Jul 2003
   8  */
   9
  10 #ifdef CAN_WITH_RTL
  11
  12 #include "../include/can.h"
  13 #include "../include/can_sysdep.h"
  14 #include "../include/main.h"
  15
  16 #include <rtl_malloc.h>
  17 #include <rtl_posixio.h>
  18 #include "../include/can_iortl.h"
  19
  20 #define __NO_VERSION__
  21 #include <linux/module.h>
  22
  23
  24 static inline
  25 int can_open_rtl_common(struct canuser_t *canuser, int open_flags)
  26 {
  27         struct msgobj_t *obj=canuser->msgobj;
  28         struct chip_t *chip;
  29         struct canque_ends_t *qends;
  30         struct canque_edge_t *edge;
  31         can_spin_irqflags_t iflags;
  32
  33         if(!obj) return -ENODEV;
  34
  35         can_msgobj_set_fl(obj,OPENED);
  36
  37         chip=obj->hostchip;
  38         if (chip) {
  39                 if (!(chip->flags & CHIP_CONFIGURED)) {
  40                         if (chip->chipspecops->chip_config(chip))
  41                                 CANMSG("Error configuring chip.\n");
  42                         else
  43                                 chip->flags |= CHIP_CONFIGURED;
  44
  45                         if (chip->chipspecops->pre_read_config(chip,obj)<0)
  46                                 CANMSG("Error initializing chip for receiving\n");
  47
  48                 }
  49         } /* End of chip configuration */
  50
  51
  52         qends = (struct canque_ends_t *)rt_malloc(sizeof(struct canque_ends_t));
  53         if(qends == NULL) goto no_qends;
  54         canqueue_ends_init_rtl(qends);
  55         canuser->qends = qends;
  56
  57         can_spin_lock_irqsave(&canuser_manipulation_lock, iflags);
  58         list_add(&canuser->peers, &obj->obj_users);
  59         can_spin_unlock_irqrestore(&canuser_manipulation_lock, iflags);
  60
  61         if(canqueue_connect_edge(edge=canque_new_edge_rtl(MAX_BUF_LENGTH),
  62                 canuser->qends, obj->qends)<0) goto no_tx_qedge;
  63
  64         if(canqueue_connect_edge(canuser->rx_edge0=canque_new_edge_rtl(MAX_BUF_LENGTH),
  65                 obj->qends, canuser->qends)<0) goto no_rx_qedge;
  66         /*FIXME: more generic model should be used there*/
  67         canque_edge_decref(canuser->rx_edge0);
  68         canque_edge_decref(edge);
  69
  70 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,50))
  71         MOD_INC_USE_COUNT;      /*is this enough for RT-Linux context ?*/
  72 #endif
  73
  74         return 0;
  75
  76     no_rx_qedge:
  77         canque_notify_bothends(edge, CANQUEUE_NOTIFY_DEAD_WANTED);
  78         canque_edge_decref(edge);
  79     no_tx_qedge:
  80         list_del(&canuser->peers);
  81         canuser->qends = NULL;
  82         canqueue_ends_dispose_kern(qends, 1);
  83
  84     no_qends:
  85
  86         return -ENOMEM;
  87 }
  88
  89
  90 int can_open_rtl_posix(struct rtl_file *fptr)
  91 {
  92         int ret;
  93         struct msgobj_t *obj;
  94         struct chip_t *chip;
  95         struct canuser_t *canuser;
  96         int minor_nr = RTL_MINOR_FROM_FILEPTR(fptr);
  97
  98         if(minor_nr>=MAX_TOT_MSGOBJS)
  99                 return -ENODEV;
 100
 101         if ( ((obj=objects_p[minor_nr]) == NULL) ||
 102                         ((chip=objects_p[minor_nr]->hostchip) == NULL) ) {
 103                 CANMSG("There is no hardware support for the device file with minor nr.: %d\n",minor_nr);
 104                 return -ENODEV;
 105         }
 106
 107         atomic_inc(&obj->obj_used);
 108         DEBUGMSG("Device %d opened %d times.\n", minor_nr, atomic_read(&obj->obj_used));
 109
 110         canuser = (struct canuser_t *)rt_malloc(sizeof(struct canuser_t));
 111         if(canuser == NULL){
 112                 ret=-ENOMEM;
 113                 goto no_canuser;
 114         }
 115         canuser->flags=CANUSER_RTL_CLIENT | CANUSER_RTL_MEM;
 116         canuser->userinfo.rtlinfo.file = fptr;
 117         canuser->msgobj = obj;
 118         canuser->magic = CAN_USER_MAGIC;
 119
 120         /*next line would solve many problems, but RT-Linux lacks this fundamental field */
 121         /*fptr->private_data = canuser;*/
 122         /*to test code I am adding this terible hack*/
 123         can_set_rtl_file_private_data(fptr,canuser);
 124
 125         ret=can_open_rtl_common(canuser, fptr->f_flags);
 126         if(ret>=0) return ret;
 127
 128         rt_free(canuser);
 129
 130     no_canuser:
 131         atomic_dec(&obj->obj_used);
 132
 133         return ret;
 134 }
 135
 136 #endif /*CAN_WITH_RTL*/