X-Git-Url: http://rtime.felk.cvut.cz/gitweb/lincan.git/blobdiff_plain/97078fff5202521b758c9081d75580880417a123..11132ea490f9e860744ee4f851c67e7fb4444231:/lincan/src/read.c

diff --git a/lincan/src/read.c b/lincan/src/read.c
index 1111401..64b2415 100644
--- a/lincan/src/read.c
+++ b/lincan/src/read.c
@@ -1,24 +1,19 @@
 /* read.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 0.7  6 Aug 2001
+ * Version lincan-0.2  9 Jul 2003
  */
 
 #define __NO_VERSION__
 #include <linux/module.h> 
 
 #include <linux/autoconf.h>
-#if defined (CONFIG_MODVERSIONS) && !defined (MODVERSIONS)
-#define MODVERSIONS
-#endif
-
-#if defined (MODVERSIONS)
-#include <linux/modversions.h>
-#endif
 
 #include <linux/version.h>
-#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,4,0))
 #include <linux/malloc.h>
 #else
 #include <linux/slab.h>
@@ -32,65 +27,49 @@
 #include "../include/ioctl.h"
 
 /* This is the 'Normal' read handler for normal transmission messages */
-inline ssize_t can_std_read(struct file *file, struct canfifo_t *fifo, 
+inline ssize_t can_std_read(struct file *file, struct canque_ends_t *qends, 
 			struct msgobj_t *obj, char *buffer, size_t length)
 {
-	int can_timeout, ret;
-	int bytes_avail = 0, bytes_to_copy = 0;
-
-	cli();
-	if (fifo->rx_readp == fifo->rx_writep) {	// Buffer is empty
+	int ret;
+	int bytes_to_copy;
+	struct canque_edge_t *qedge;
+	struct canque_slot_t *slot;
+	
+	ret=canque_test_outslot(qends, &qedge, &slot);
+	if(ret<0){
 		if (file->f_flags & O_NONBLOCK) {
-			sti();
 			return -EAGAIN;
 		}
-		obj->ret = 0;
-		can_timeout = interruptible_sleep_on_timeout(&fifo->readq,
-								CANTIMEOUT);
-		sti();
-		if (signal_pending(current)) {
-			DEBUGMSG("Rx interrupted\n");
-			return -EINTR;
-		}
-		if (!can_timeout) {
-			DEBUGMSG("no data received\n");
-			return 0;
+		ret=canque_get_outslot_wait_kern(qends, &qedge, &slot);
+		if(ret<0){
+			if (signal_pending(current)) {
+				DEBUGMSG("Rx interrupted\n");
+				return -EINTR;
+			}
+			/*if (!can_timeout) {
+				DEBUGMSG("no data received\n");
+				return 0;
+			}*/
+			return -EIO;
 		}
-		if (obj->ret < 0)
-			return obj->ret;
 	}
-	/* Calculate available bytes in the buffer */
-	cli();
-	bytes_avail = ((int)fifo->rx_readp < (int)fifo->rx_writep) ?
-			((int)fifo->rx_writep - (int)fifo->rx_readp) :
-			((int)fifo->rx_writep - (int)fifo->rx_readp + 
-							(int)fifo->rx_size);
-	sti();
-		
-	bytes_to_copy = (length < bytes_avail) ? length : bytes_avail;
-	ret = bytes_to_copy;
-
-	/* printk(KERN_CRIT "can RxFIFO b:%x e:%x bs:%x msg:%x rp:%x wp:%x btc:%x\n",
-	       fifo->buf_rx_entry, fifo->buf_rx_entry+MAX_BUF_LENGTH,
-	       fifo->rx_size, sizeof(struct canmsg_t),
-	       fifo->rx_readp, fifo->rx_writep, bytes_to_copy); */
-
-
-	/* Copy the data to user space */
+	
+	copy_to_user(buffer, &slot->msg, sizeof(struct canmsg_t));
+	canque_free_outslot(qends, qedge, slot);
+	buffer += sizeof(struct canmsg_t);
+	bytes_to_copy = length-sizeof(struct canmsg_t);
+	
 	while (bytes_to_copy > 0) {
-		       
-		
-		copy_to_user(buffer, fifo->rx_readp, sizeof(struct canmsg_t));
+		ret=canque_test_outslot(qends, &qedge, &slot);
+		if(ret<0)
+			break;
+		copy_to_user(buffer, &slot->msg, sizeof(struct canmsg_t));
+		canque_free_outslot(qends, qedge, slot);
 		buffer += sizeof(struct canmsg_t);
 		bytes_to_copy -= sizeof(struct canmsg_t);
-		fifo->rx_readp++;
-		if (fifo->rx_readp >= fifo->buf_rx_entry + MAX_BUF_LENGTH)
-			fifo->rx_readp = fifo->buf_rx_entry;
-
-	        /* printk(KERN_CRIT "can RxFIFO rp%x\n",fifo->rx_readp); */
 	}
 
-	return ret;
+	return length-bytes_to_copy;
 }
 
 /* This is the 'RTR' read handler for remote transmission request messages */
@@ -160,12 +139,18 @@ inline ssize_t can_rtr_read(struct chip_t *chip, struct msgobj_t *obj,
 
 ssize_t can_read(struct file *file, char *buffer, size_t length, loff_t *offset)
 {
+	struct canuser_t *canuser = (struct canuser_t*)(file->private_data);
 	struct msgobj_t *obj;
 	struct chip_t *chip;
-	struct canfifo_t *fifo;
 	struct canmsg_t read_msg;
+	struct canque_ends_t *qends;
 	int ret=0;
 
+	if(!canuser || (canuser->magic != CAN_USER_MAGIC)){
+		CANMSG("can_close: bad canuser magic\n");
+		return -ENODEV;
+	}
+
 	if (length < sizeof(struct canmsg_t)) {
 		DEBUGMSG("Trying to read less bytes than a CAN message, \n");
 		DEBUGMSG("this will always return zero.\n");
@@ -177,25 +162,23 @@ ssize_t can_read(struct file *file, char *buffer, size_t length, loff_t *offset)
 		length = 8 * sizeof(struct canmsg_t);
 	}
 	/* Initialize hardware pointers */
-	if ( (obj = objects_p[MINOR_NR]) == NULL) {
+	obj = canuser->msgobj;
+	if (obj == NULL) {
 		CANMSG("Could not assign buffer structure\n");
 		return -1;
 	}
+	qends = canuser->qends;
 	if ( (chip = obj->hostchip) == NULL) {
 		CANMSG("Device is not correctly configured,\n");
 		CANMSG("please reload the driver.\n");
 		return -1;
 	}
-	if ( (fifo = obj->fifo) == NULL) {
-		CANMSG("Could not assign buffer memory.\n");
-		return -1;
-	}
 
 	copy_from_user(&read_msg, buffer, sizeof(struct canmsg_t));
 	if (read_msg.flags & MSG_RTR)
 		ret = can_rtr_read(chip, obj, buffer);
 	else
-		ret = can_std_read(file, fifo, obj, buffer, length);
+		ret = can_std_read(file, qends, obj, buffer, length);
 
 	return ret;
 }