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-0.3  17 Jun 2004
   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 canchip_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         /* mark memory as allocated from RTL memory pool */
  56         qends->ends_flags|=CAN_ENDSF_MEM_RTL;
  57         canuser->qends = qends;
  58
  59         can_spin_lock_irqsave(&canuser_manipulation_lock, iflags);
  60         list_add(&canuser->peers, &obj->obj_users);
  61         can_spin_unlock_irqrestore(&canuser_manipulation_lock, iflags);
  62
  63         if(canqueue_connect_edge(edge=canque_new_edge_rtl(MAX_BUF_LENGTH),
  64                 canuser->qends, obj->qends)<0) goto no_tx_qedge;
  65
  66         if(canqueue_connect_edge(canuser->rx_edge0=canque_new_edge_rtl(MAX_BUF_LENGTH),
  67                 obj->qends, canuser->qends)<0) goto no_rx_qedge;
  68         /*FIXME: more generic model should be used there*/
  69         canque_edge_decref(canuser->rx_edge0);
  70         canque_edge_decref(edge);
  71
  72 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,50))
  73         MOD_INC_USE_COUNT;      /*is this enough for RT-Linux context ?*/
  74 #endif
  75
  76         return 0;
  77
  78     no_rx_qedge:
  79         canque_notify_bothends(edge, CANQUEUE_NOTIFY_DEAD_WANTED);
  80         canque_edge_decref(edge);
  81     no_tx_qedge:
  82         list_del(&canuser->peers);
  83         canuser->qends = NULL;
  84         canqueue_ends_dispose_kern(qends, 1);
  85
  86     no_qends:
  87
  88         return -ENOMEM;
  89 }
  90
  91
  92 int can_open_rtl_posix(struct rtl_file *fptr)
  93 {
  94         int ret;
  95         struct msgobj_t *obj;
  96         struct canchip_t *chip;
  97         struct canuser_t *canuser;
  98         int minor_nr = RTL_MINOR_FROM_FILEPTR(fptr);
  99
 100         if(minor_nr>=MAX_TOT_MSGOBJS)
 101                 return -ENODEV;
 102
 103         if ( ((obj=objects_p[minor_nr]) == NULL) ||
 104                         ((chip=objects_p[minor_nr]->hostchip) == NULL) ) {
 105                 CANMSG("There is no hardware support for the device file with minor nr.: %d\n",minor_nr);
 106                 return -ENODEV;
 107         }
 108
 109         atomic_inc(&obj->obj_used);
 110         DEBUGMSG("Device %d opened %d times.\n", minor_nr, atomic_read(&obj->obj_used));
 111
 112         canuser = (struct canuser_t *)rt_malloc(sizeof(struct canuser_t));
 113         if(canuser == NULL){
 114                 ret=-ENOMEM;
 115                 goto no_canuser;
 116         }
 117         canuser->flags=CANUSER_RTL_CLIENT | CANUSER_RTL_MEM;
 118         canuser->userinfo.rtlinfo.file = fptr;
 119         canuser->msgobj = obj;
 120         canuser->magic = CAN_USER_MAGIC;
 121
 122         /*next line would solve many problems, but RT-Linux lacks this fundamental field */
 123         /*fptr->private_data = canuser;*/
 124         /*to test code I am adding this terible hack*/
 125         can_set_rtl_file_private_data(fptr,canuser);
 126
 127         ret=can_open_rtl_common(canuser, fptr->f_flags);
 128         if(ret>=0) return ret;
 129
 130         rt_free(canuser);
 131
 132     no_canuser:
 133         atomic_dec(&obj->obj_used);
 134
 135         return ret;
 136 }
 137
 138 #endif /*CAN_WITH_RTL*/