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 Nov 2004
10 #include "../include/can.h"
11 #include "../include/can_sysdep.h"
12 #include "../include/main.h"
13 #include "../include/read.h"
14 #include "../include/ioctl.h"
16 /* This is the 'RTR' read handler for remote transmission request messages */
17 int can_ioctl_remote_read(struct canuser_t *canuser, struct canmsg_t *rtr_msg,
18 unsigned long rtr_id, int options)
20 can_spin_irqflags_t flags;
21 struct rtr_id *rtr_current, *new_rtr_entry;
23 struct canchip_t *chip;
24 /*struct canque_ends_t *qends;*/
26 DEBUGMSG("Remote transmission request\n");
28 /*qends = canuser->qends;*/
30 /* Initialize hardware pointers */
31 obj = canuser->msgobj;
33 CANMSG("Could not assign buffer structure\n");
37 if ( (chip = obj->hostchip) == NULL) {
38 CANMSG("Device is not correctly configured,\n");
39 CANMSG("please reload the driver.\n");
43 can_spin_lock_irqsave(&hardware_p->rtr_lock, flags);
44 if (hardware_p->rtr_queue == NULL) { //No remote messages pending
45 new_rtr_entry=(struct rtr_id *)kmalloc(sizeof(struct rtr_id),GFP_ATOMIC);
46 if (new_rtr_entry == NULL) {
47 can_spin_unlock_irqrestore(&hardware_p->rtr_lock,
51 hardware_p->rtr_queue=new_rtr_entry;
54 rtr_current=hardware_p->rtr_queue;
55 while (rtr_current->next != NULL)
56 rtr_current=rtr_current->next;
57 new_rtr_entry=(struct rtr_id *)kmalloc(sizeof(struct rtr_id),GFP_ATOMIC);
58 rtr_current->next=new_rtr_entry;
60 init_waitqueue_head(&new_rtr_entry->rtr_wq);
61 new_rtr_entry->id = rtr_id;
62 new_rtr_entry->rtr_message = rtr_msg;
63 new_rtr_entry->next=NULL;
65 can_spin_unlock_irqrestore(&hardware_p->rtr_lock, flags);
67 /* Send remote transmission request */
68 chip->chipspecops->remote_request(chip,obj);
70 interruptible_sleep_on(&new_rtr_entry->rtr_wq);
72 can_spin_lock_irqsave(&hardware_p->rtr_lock, flags);
73 if (hardware_p->rtr_queue == new_rtr_entry) {
74 if (new_rtr_entry->next != NULL)
75 hardware_p->rtr_queue=new_rtr_entry->next;
77 hardware_p->rtr_queue=NULL;
80 rtr_current=hardware_p->rtr_queue;
81 while (rtr_current->next != new_rtr_entry)
82 rtr_current=rtr_current->next;
83 if (new_rtr_entry->next != NULL)
84 rtr_current->next=new_rtr_entry->next;
86 rtr_current->next=NULL;
88 can_spin_unlock_irqrestore(&hardware_p->rtr_lock, flags);