Separated normal read and RTR assisted read transfer.

[lincan.git] / lincan / src / ioctl_remote.c

diff --git a/lincan/src/ioctl_remote.c b/lincan/src/ioctl_remote.c
new file mode 100644 (file)
index 0000000..68f3670
--- /dev/null
+++ b/lincan/src/ioctl_remote.c
@@ -0,0 +1,93 @@
+/* ioctl_remote.c
+ * Linux CAN-bus device driver.
+ * Written by Arnaud Westenberg email:arnaud@wanadoo.nl
+ * Rewritten for new CAN queues by Pavel Pisa - OCERA team member
+ * email:pisa@cmp.felk.cvut.cz
+ * This software is released under the GPL-License.
+ * Version lincan-0.3  17 Nov 2004
+ */
+
+#include "../include/can.h"
+#include "../include/can_sysdep.h"
+#include "../include/main.h"
+#include "../include/read.h"
+#include "../include/ioctl.h"
+
+/* This is the 'RTR' read handler for remote transmission request messages */
+int can_ioctl_remote_read(struct canuser_t *canuser, struct canmsg_t *rtr_msg,
+                          unsigned long rtr_id, int options)
+{
+       can_spin_irqflags_t flags;
+       struct rtr_id *rtr_current, *new_rtr_entry;
+       struct msgobj_t *obj;
+       struct canchip_t *chip;
+       /*struct canque_ends_t *qends;*/
+       
+       DEBUGMSG("Remote transmission request\n");
+
+       /*qends = canuser->qends;*/
+
+       /* Initialize hardware pointers */
+       obj = canuser->msgobj;
+       if (obj == NULL) {
+               CANMSG("Could not assign buffer structure\n");
+               return -ENODEV;
+       }
+
+       if ( (chip = obj->hostchip) == NULL) {
+               CANMSG("Device is not correctly configured,\n");
+               CANMSG("please reload the driver.\n");
+               return -ENODEV;
+       }
+
+       can_spin_lock_irqsave(&hardware_p->rtr_lock, flags);
+       if (hardware_p->rtr_queue == NULL) { //No remote messages pending
+               new_rtr_entry=(struct rtr_id *)kmalloc(sizeof(struct rtr_id),GFP_ATOMIC);
+               if (new_rtr_entry == NULL) {
+                       can_spin_unlock_irqrestore(&hardware_p->rtr_lock, 
+                                                               flags);
+                       return -ENOMEM;
+               }
+               hardware_p->rtr_queue=new_rtr_entry;
+       }
+       else {
+               rtr_current=hardware_p->rtr_queue;
+               while (rtr_current->next != NULL)
+                       rtr_current=rtr_current->next;
+               new_rtr_entry=(struct rtr_id *)kmalloc(sizeof(struct rtr_id),GFP_ATOMIC);
+               rtr_current->next=new_rtr_entry;
+       }
+       init_waitqueue_head(&new_rtr_entry->rtr_wq);
+       new_rtr_entry->id = rtr_id;
+       new_rtr_entry->rtr_message = rtr_msg;
+       new_rtr_entry->next=NULL;
+
+       can_spin_unlock_irqrestore(&hardware_p->rtr_lock, flags);
+
+       /* Send remote transmission request */
+       chip->chipspecops->remote_request(chip,obj);
+       obj->ret = 0;
+       interruptible_sleep_on(&new_rtr_entry->rtr_wq);
+
+       can_spin_lock_irqsave(&hardware_p->rtr_lock, flags);
+       if (hardware_p->rtr_queue == new_rtr_entry) {
+               if (new_rtr_entry->next != NULL) 
+                       hardware_p->rtr_queue=new_rtr_entry->next;
+               else
+                       hardware_p->rtr_queue=NULL;
+       }
+       else {
+               rtr_current=hardware_p->rtr_queue;
+               while (rtr_current->next != new_rtr_entry)
+                       rtr_current=rtr_current->next;
+               if (new_rtr_entry->next != NULL)
+                       rtr_current->next=new_rtr_entry->next;
+               else
+                       rtr_current->next=NULL;
+       }
+       can_spin_unlock_irqrestore(&hardware_p->rtr_lock, flags);
+       kfree(new_rtr_entry);
+
+       return obj->ret;
+}
+