X-Git-Url: http://rtime.felk.cvut.cz/gitweb/lincan.git/blobdiff_plain/786c7d54e8d820e89997e507c29ea716c0d55fd9..a682f9de48bcce43fba6141fbdb4d451914e0bb4:/lincan/src/read.c diff --git a/lincan/src/read.c b/lincan/src/read.c index 1111401..c16c76b 100644 --- a/lincan/src/read.c +++ b/lincan/src/read.c @@ -1,203 +1,74 @@ /* 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-0.3 17 Jun 2004 */ -#define __NO_VERSION__ -#include - -#include -#if defined (CONFIG_MODVERSIONS) && !defined (MODVERSIONS) -#define MODVERSIONS -#endif - -#if defined (MODVERSIONS) -#include -#endif - -#include -#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)) -#include -#else -#include -#endif -#include -#include -#include - +#include "../include/can.h" +#include "../include/can_sysdep.h" #include "../include/main.h" #include "../include/read.h" -#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, - struct msgobj_t *obj, char *buffer, size_t length) +ssize_t can_read(struct file *file, char *buffer, size_t length, loff_t *offset) { - int can_timeout, ret; - int bytes_avail = 0, bytes_to_copy = 0; + struct canuser_t *canuser = (struct canuser_t*)(file->private_data); + struct canque_ends_t *qends; + int bytes_to_copy; + struct canque_edge_t *qedge; + struct canque_slot_t *slot; + int ret; + + if(!canuser || (canuser->magic != CAN_USER_MAGIC)){ + CANMSG("can_read: 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"); + return 0; + } + + qends = canuser->qends; - cli(); - if (fifo->rx_readp == fifo->rx_writep) { // Buffer is empty + 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; + 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 (!can_timeout) { - DEBUGMSG("no data received\n"); - return 0; - } - 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; -} - -/* This is the 'RTR' read handler for remote transmission request messages */ -inline ssize_t can_rtr_read(struct chip_t *chip, struct msgobj_t *obj, - char *buffer) -{ - unsigned long flags; - struct rtr_id *rtr_current, *new_rtr_entry; - struct canmsg_t read_msg; - - DEBUGMSG("Remote transmission request\n"); - 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) { - 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; - } -#if (LINUX_VERSION_CODE <= KERNEL_VERSION(2,3,0)) - init_waitqueue(&new_rtr_entry->rtr_wq); -#else - init_waitqueue_head(&new_rtr_entry->rtr_wq); -#endif - new_rtr_entry->id = read_msg.id; - new_rtr_entry->rtr_message = &read_msg; - new_rtr_entry->next=NULL; - - 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); - - spin_lock_irqsave(&hardware_p->rtr_lock, flags); - copy_to_user(buffer, &read_msg, sizeof(struct canmsg_t)); - 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; - } - spin_unlock_irqrestore(&hardware_p->rtr_lock, flags); - kfree(new_rtr_entry); - - return obj->ret; + return length-bytes_to_copy; } -ssize_t can_read(struct file *file, char *buffer, size_t length, loff_t *offset) -{ - struct msgobj_t *obj; - struct chip_t *chip; - struct canfifo_t *fifo; - struct canmsg_t read_msg; - int ret=0; - - if (length < sizeof(struct canmsg_t)) { - DEBUGMSG("Trying to read less bytes than a CAN message, \n"); - DEBUGMSG("this will always return zero.\n"); - return 0; - } - if (length > 8 * sizeof(struct canmsg_t)) { - DEBUGMSG("Reading more than 8 CAN messages, this is not supported.\n"); - DEBUGMSG("Defaulting to 8 messages.\n"); - length = 8 * sizeof(struct canmsg_t); - } - /* Initialize hardware pointers */ - if ( (obj = objects_p[MINOR_NR]) == NULL) { - CANMSG("Could not assign buffer structure\n"); - return -1; - } - 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); - - return ret; -} - -