/*
* Read n bytes from the user memory and writes them into the board memory.
*
* card: the board
* to: the destination address (in the board memory)
* from: the source address (in the userspace memory)
* n: number of bytes
*
* Return: 0 if OK, <0 if error.
*/
int copy_from_user_to_pam(tpam_card *card, void *to, const void *from, u32 n) {
void *page;
u32 count;
/* allocate a free page for the data transfer */
if (!(page = (void *)__get_free_page(GFP_KERNEL))) {
printk(KERN_ERR "TurboPAM(copy_from_user_to_pam): "
"get_free_page failed\n");
return -ENOMEM;
}
while (n) {
count = n < PAGE_SIZE ? n : PAGE_SIZE;
/* copy data from the user memory into the kernel memory */
if (copy_from_user(page, from, count)) {
/* this can fail... */
free_page((u32)page);
return -EFAULT;
}
/* copy it from the kernel memory into the board memory */
spin_lock_irq(&card->lock);
copy_to_pam(card, to, page, count);
spin_unlock_irq(&card->lock);
from += count;
to += count;
n -= count;
}
/* release allocated memory */
free_page((u32)page);
return 0;
}
/*
* Try to send a packet from the board's send queue or from the channel's
* send queue.
*
* card: the board.
* channel: the channel (if NULL, the packet will be taken from the
* board's send queue. If not, it will be taken from the
* channel's send queue.
*
* Return: 0 if tpam_send_tq must try another card/channel combination
* (meaning that no packet has been send), 1 if no more packets
* can be send at that time (a packet has been send or the card is
* still busy from a previous send).
*/
static int tpam_sendpacket(tpam_card *card, tpam_channel *channel) {
struct sk_buff *skb;
u32 hpic;
u32 downloadptr;
skb_header *skbh;
u32 waiting_too_long;
dprintk("TurboPAM(tpam_sendpacket), card=%d, channel=%d\n",
card->id, channel ? channel->num : -1);
if (channel) {
/* dequeue a packet from the channel's send queue */
if (!(skb = skb_dequeue(&channel->sendq))) {
dprintk("TurboPAM(tpam_sendpacket): "
"card=%d, channel=%d, no packet\n",
card->id, channel->num);
return 0;
}
/* if the channel is not ready to receive, requeue the packet
* and return 0 to give a chance to another channel */
if (!channel->readytoreceive) {
dprintk("TurboPAM(tpam_sendpacket): "
"card=%d, channel=%d, channel not ready\n",
card->id, channel->num);
skb_queue_head(&channel->sendq, skb);
return 0;
}
/* grab the board lock */
spin_lock_irq(&card->lock);
/* if the board is busy, requeue the packet and return 1 since
* there is no need to try another channel */
if (card->busy) {
dprintk("TurboPAM(tpam_sendpacket): "
"card=%d, channel=%d, card busy\n",
card->id, channel->num);
skb_queue_head(&channel->sendq, skb);
spin_unlock_irq(&card->lock);
return 1;
}
}
else {
/* dequeue a packet from the board's send queue */
if (!(skb = skb_dequeue(&card->sendq))) {
dprintk("TurboPAM(tpam_sendpacket): "
"card=%d, no packet\n", card->id);
return 0;
}
/* grab the board lock */
spin_lock_irq(&card->lock);
/* if the board is busy, requeue the packet and return 1 since
* there is no need to try another channel */
if (card->busy) {
dprintk("TurboPAM(tpam_sendpacket): "
"card=%d, card busy\n", card->id);
skb_queue_head(&card->sendq, skb);
spin_unlock_irq(&card->lock);
return 1;
}
}
/* wait for the board to become ready */
waiting_too_long = 0;
do {
hpic = readl(card->bar0 + TPAM_HPIC_REGISTER);
if (waiting_too_long++ > 0xfffffff) {
spin_unlock_irq(&card->lock);
printk(KERN_ERR "TurboPAM(tpam_sendpacket): "
"waiting too long...\n");
return 1;
}
} while (hpic & 0x00000002);
skbh = (skb_header *)skb->data;
dprintk("TurboPAM(tpam_sendpacket): "
"card=%d, card ready, sending %d/%d bytes\n",
card->id, skbh->size, skbh->data_size);
/* get the board's download pointer */
downloadptr = copy_from_pam_dword(card,
(void *)TPAM_DOWNLOADPTR_REGISTER);
/* copy the packet to the board at the downloadptr location */
copy_to_pam(card, (void *)downloadptr, skb->data + sizeof(skb_header),
skbh->size);
if (skbh->data_size)
/* if there is some data in the packet, copy it too */
copy_to_pam(card, (void *)downloadptr + sizeof(pci_mpb) + 4096,
skb->data + sizeof(skb_header) + skbh->size,
skbh->data_size);
/* card will become busy right now */
card->busy = 1;
/* interrupt the board */
copy_to_pam_dword(card, (void *)TPAM_ACKDOWNLOAD_REGISTER, 0);
readl(card->bar0 + TPAM_DSPINT_REGISTER);
/* release the lock */
spin_unlock_irq(&card->lock);
/* if a data ack was requested by the ISDN link layer, send it now */
if (skbh->ack) {
isdn_ctrl ctrl;
ctrl.driver = card->id;
ctrl.command = ISDN_STAT_BSENT;
ctrl.arg = channel->num;
ctrl.parm.length = skbh->ack_size;
(* card->interface.statcallb)(&ctrl);
}
/* free the sk_buff */
kfree_skb(skb);
return 1;
}
