drv.c

linux-2.6.15.6

/*
 * PCBIT-D interface with isdn4linux
 *
 * Copyright (C) 1996 Universidade de Lisboa
 * 
 * Written by Pedro Roque Marques ([e-mail])
 *
 * This software may be used and distributed according to the terms of 
 * the GNU General Public License, incorporated herein by reference.
 */

/*
 *	Fixes:
 *
 *	Nuno Grilo	<[e-mail]>
 *      fixed msn_list NULL pointer dereference.
 *		
 */

#include <linux/module.h>

#include <linux/sched.h>

#include <linux/kernel.h>

#include <linux/types.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/string.h>
#include <linux/skbuff.h>

#include <linux/isdnif.h>
#include <asm/string.h>
#include <asm/io.h>
#include <linux/ioport.h>

#include "pcbit.h"
#include "edss1.h"
#include "layer2.h"
#include "capi.h"


extern ushort last_ref_num;

static int pcbit_ioctl(isdn_ctrl* ctl);

static char* pcbit_devname[MAX_PCBIT_CARDS] = {
	"pcbit0",
	"pcbit1",
	"pcbit2",
	"pcbit3"
};

/*
 * prototypes
 */

static int pcbit_command(isdn_ctrl* ctl);
static int pcbit_stat(u_char __user * buf, int len, int, int);
static int pcbit_xmit(int driver, int chan, int ack, struct sk_buff *skb);
static int pcbit_writecmd(const u_char __user *, int, int, int);

static int set_protocol_running(struct pcbit_dev * dev);

static void pcbit_clear_msn(struct pcbit_dev *dev);
static void pcbit_set_msn(struct pcbit_dev *dev, char *list);
static int pcbit_check_msn(struct pcbit_dev *dev, char *msn);


extern void pcbit_deliver(void * data);

int pcbit_init_dev(int board, int mem_base, int irq)
{
	struct pcbit_dev *dev;
	isdn_if *dev_if;

	if ((dev=kmalloc(sizeof(struct pcbit_dev), GFP_KERNEL)) == NULL)
	{
		printk("pcbit_init: couldn't malloc pcbit_dev struct\n");
		return -ENOMEM;
	}

	dev_pcbit[board] = dev;
	memset(dev, 0, sizeof(struct pcbit_dev));
	init_waitqueue_head(&dev->set_running_wq);
	spin_lock_init(&dev->lock);

	if (mem_base >= 0xA0000 && mem_base <= 0xFFFFF ) {
		dev->ph_mem = mem_base;
		if (!request_mem_region(dev->ph_mem, 4096, "PCBIT mem")) {
			printk(KERN_WARNING
				"PCBIT: memory region %lx-%lx already in use\n",
				dev->ph_mem, dev->ph_mem + 4096);
			kfree(dev);
			dev_pcbit[board] = NULL;
			return -EACCES;
		}
		dev->sh_mem = ioremap(dev->ph_mem, 4096);
	}
	else 
	{
		printk("memory address invalid");
		kfree(dev);
		dev_pcbit[board] = NULL;
		return -EACCES;
	}

	dev->b1 = kmalloc(sizeof(struct pcbit_chan), GFP_KERNEL);
	if (!dev->b1) {
		printk("pcbit_init: couldn't malloc pcbit_chan struct\n");
		iounmap(dev->sh_mem);
		release_mem_region(dev->ph_mem, 4096);
		kfree(dev);
		return -ENOMEM;
	}
    
	dev->b2 = kmalloc(sizeof(struct pcbit_chan), GFP_KERNEL);
	if (!dev->b2) {
		printk("pcbit_init: couldn't malloc pcbit_chan struct\n");
		kfree(dev->b1);
		iounmap(dev->sh_mem);
		release_mem_region(dev->ph_mem, 4096);
		kfree(dev);
		return -ENOMEM;
	}

	memset(dev->b1, 0, sizeof(struct pcbit_chan));
	memset(dev->b2, 0, sizeof(struct pcbit_chan));
	dev->b2->id = 1;

	INIT_WORK(&dev->qdelivery, pcbit_deliver, dev);

	/*
	 *  interrupts
	 */

	if (request_irq(irq, &pcbit_irq_handler, 0, pcbit_devname[board], dev) != 0) 
	{
		kfree(dev->b1);
		kfree(dev->b2);
		iounmap(dev->sh_mem);
		release_mem_region(dev->ph_mem, 4096);
		kfree(dev);
		dev_pcbit[board] = NULL;
		return -EIO;
	}

	dev->irq = irq;

	/* next frame to be received */
	dev->rcv_seq = 0;
	dev->send_seq = 0;
	dev->unack_seq = 0;

	dev->hl_hdrlen = 16;

	dev_if = kmalloc(sizeof(isdn_if), GFP_KERNEL);

	if (!dev_if) {
		free_irq(irq, dev);
		kfree(dev->b1);
		kfree(dev->b2);
		iounmap(dev->sh_mem);
		release_mem_region(dev->ph_mem, 4096);
		kfree(dev);
		dev_pcbit[board] = NULL;
		return -EIO;
	}

	dev->dev_if = dev_if;

	dev_if->owner = THIS_MODULE;

	dev_if->channels = 2;
	
	dev_if->features = (ISDN_FEATURE_P_EURO  | ISDN_FEATURE_L3_TRANS | 
			    ISDN_FEATURE_L2_HDLC | ISDN_FEATURE_L2_TRANS );

	dev_if->writebuf_skb = pcbit_xmit;
	dev_if->hl_hdrlen = 16;

	dev_if->maxbufsize = MAXBUFSIZE;
	dev_if->command  = pcbit_command;
	
	dev_if->writecmd = pcbit_writecmd;
	dev_if->readstat = pcbit_stat;


	strcpy(dev_if->id, pcbit_devname[board]);

	if (!register_isdn(dev_if)) {
		free_irq(irq, dev);
		kfree(dev->b1);
		kfree(dev->b2);
		iounmap(dev->sh_mem);
		release_mem_region(dev->ph_mem, 4096);
		kfree(dev);
		dev_pcbit[board] = NULL;
		return -EIO;
	}

	dev->id = dev_if->channels;


	dev->l2_state = L2_DOWN;
	dev->free = 511;

	/*
	 * set_protocol_running(dev);
	 */

	return 0;
}

#ifdef MODULE
void pcbit_terminate(int board)
{
	struct pcbit_dev * dev;

	dev = dev_pcbit[board];

	if (dev) {
	     /* unregister_isdn(dev->dev_if); */
		free_irq(dev->irq, dev);
		pcbit_clear_msn(dev);
		kfree(dev->dev_if);
		if (dev->b1->fsm_timer.function)
			del_timer(&dev->b1->fsm_timer);
		if (dev->b2->fsm_timer.function)
			del_timer(&dev->b2->fsm_timer);
		kfree(dev->b1);
		kfree(dev->b2);
		iounmap(dev->sh_mem);
		release_mem_region(dev->ph_mem, 4096);
		kfree(dev);
	}
}
#endif

static int pcbit_command(isdn_ctrl* ctl)
{
	struct pcbit_dev  *dev;
	struct pcbit_chan *chan;
	struct callb_data info;

	dev = finddev(ctl->driver);

	if (!dev)
	{
		printk("pcbit_command: unknown device\n");
		return -1;
	}

	chan = (ctl->arg & 0x0F) ? dev->b2 : dev->b1;


	switch(ctl->command) {
	case ISDN_CMD_IOCTL:
		return pcbit_ioctl(ctl);
		break;
	case ISDN_CMD_DIAL:
		info.type = EV_USR_SETUP_REQ;
		info.data.setup.CalledPN = (char *) &ctl->parm.setup.phone;
		pcbit_fsm_event(dev, chan, EV_USR_SETUP_REQ, &info);
		break;
	case ISDN_CMD_ACCEPTD:
		pcbit_fsm_event(dev, chan, EV_USR_SETUP_RESP, NULL);
		break;
	case ISDN_CMD_ACCEPTB:
		printk("ISDN_CMD_ACCEPTB - not really needed\n");
		break;
	case ISDN_CMD_HANGUP:
		pcbit_fsm_event(dev, chan, EV_USR_RELEASE_REQ, NULL);
		break;
	case ISDN_CMD_SETL2:
		chan->proto = (ctl->arg >> 8);
		break;
	case ISDN_CMD_CLREAZ:
		pcbit_clear_msn(dev);
		break;
	case ISDN_CMD_SETEAZ:
		pcbit_set_msn(dev, ctl->parm.num);
		break;
	case ISDN_CMD_SETL3:
		if ((ctl->arg >> 8) != ISDN_PROTO_L3_TRANS)
			printk(KERN_DEBUG "L3 protocol unknown\n");
		break;
	default:
		printk(KERN_DEBUG "pcbit_command: unknown command\n");
		break;
	};

	return 0;
}

/*
 * Another Hack :-(
 * on some conditions the board stops sending TDATA_CONFs
 * let's see if we can turn around the problem
 */

#ifdef BLOCK_TIMER
static void pcbit_block_timer(unsigned long data)
{
	struct pcbit_chan *chan;
	struct pcbit_dev * dev;
	isdn_ctrl ictl;

	chan = (struct pcbit_chan *) data;

	dev = chan2dev(chan);

	if (dev == NULL) {
		printk(KERN_DEBUG "pcbit: chan2dev failed\n");
		return;
	}

	del_timer(&chan->block_timer);
	chan->block_timer.function = NULL;

#ifdef DEBUG
	printk(KERN_DEBUG "pcbit_block_timer\n");
#endif	
	chan->queued = 0;
	ictl.driver = dev->id;
	ictl.command = ISDN_STAT_BSENT;
	ictl.arg = chan->id;
	dev->dev_if->statcallb(&ictl);     
}
#endif

static int pcbit_xmit(int driver, int chnum, int ack, struct sk_buff *skb)
{
	ushort hdrlen;
	int refnum, len;
	struct pcbit_chan * chan;
	struct pcbit_dev *dev;

	dev = finddev(driver);
	if (dev == NULL)
	{
		printk("finddev returned NULL");
		return -1;
	}

	chan = chnum ? dev->b2 : dev->b1;


	if (chan->fsm_state != ST_ACTIVE)
		return -1;

	if (chan->queued >= MAX_QUEUED )
	{
#ifdef DEBUG_QUEUE
		printk(KERN_DEBUG 
		       "pcbit: %d packets already in queue - write fails\n",
		       chan->queued);
#endif
		/*
		 * packet stays on the head of the device queue
		 * since dev_start_xmit will fail
		 * see net/core/dev.c
		 */
#ifdef BLOCK_TIMER
		if (chan->block_timer.function == NULL) {
			init_timer(&chan->block_timer);
			chan->block_timer.function =  &pcbit_block_timer;
			chan->block_timer.data = (long) chan;
			chan->block_timer.expires = jiffies + 1 * HZ;
			add_timer(&chan->block_timer);
		}
#endif		
		return 0;	                 
	}


	chan->queued++;
	
        len = skb->len;

	hdrlen = capi_tdata_req(chan, skb);

	refnum = last_ref_num++ & 0x7fffU;
	chan->s_refnum = refnum;

	pcbit_l2_write(dev, MSG_TDATA_REQ, refnum, skb, hdrlen);

	return len;
}

static int pcbit_writecmd(const u_char __user *buf, int len, int driver, int channel)
{
	struct pcbit_dev * dev;
	int i, j;
	const u_char * loadbuf;
	u_char * ptr = NULL;
	u_char *cbuf;

	int errstat;

	dev = finddev(driver);

	if (!dev)
	{
		printk("pcbit_writecmd: couldn't find device");
		return -ENODEV;
	}

	switch(dev->l2_state) {
	case L2_LWMODE:
		/* check (size <= rdp_size); write buf into board */
		if (len < 0 || len > BANK4 + 1 || len > 1024)
		{
			printk("pcbit_writecmd: invalid length %d\n", len);
			return -EINVAL;
		}

		cbuf = kmalloc(len, GFP_KERNEL);
		if (!cbuf)
			return -ENOMEM;

		if (copy_from_user(cbuf, buf, len)) {
			kfree(cbuf);
			return -EFAULT;
		}
		memcpy_toio(dev->sh_mem, cbuf, len);
		kfree(cbuf);
		return len;
	case L2_FWMODE:
		/* this is the hard part */
		/* dumb board */
		/* get it into kernel space */
		if ((ptr = kmalloc(len, GFP_KERNEL))==NULL)
			return -ENOMEM;
		if (copy_from_user(ptr, buf, len)) {
			kfree(ptr);
			return -EFAULT;
		}
		loadbuf = ptr;
    
		errstat = 0;

		for (i=0; i < len; i++)
		{
			for(j=0; j < LOAD_RETRY; j++)
				if (!(readb(dev->sh_mem + dev->loadptr)))
					break;

			if (j == LOAD_RETRY)
			{
				errstat = -ETIME;
				printk("TIMEOUT i=%d\n", i);
				break;
			}
			writeb(loadbuf[i], dev->sh_mem + dev->loadptr + 1);
			writeb(0x01, dev->sh_mem + dev->loadptr);

			dev->loadptr += 2;
			if (dev->loadptr > LOAD_ZONE_END)
				dev->loadptr = LOAD_ZONE_START;
		}
		kfree(ptr);

		return errstat ? errstat : len;
	default:
		return -EBUSY;
	}
}

/*
 *  demultiplexing of messages
 *
 */

void pcbit_l3_receive(struct pcbit_dev * dev, ulong msg, 
			     struct sk_buff * skb,
			     ushort hdr_len, ushort refnum)
{
	struct pcbit_chan *chan;
	struct sk_buff *skb2;
	unsigned short len;
	struct callb_data cbdata;
	int complete, err;
	isdn_ctrl ictl;

	switch(msg) {

	case MSG_TDATA_IND:
		if (!(chan = capi_channel(dev, skb))) {
			printk(KERN_WARNING 
			       "CAPI header: unknown channel id\n");
			break;
		}
		chan->r_refnum = skb->data[7];
		skb_pull(skb, 8);

		dev->dev_if->rcvcallb_skb(dev->id, chan->id, skb);

		if (capi_tdata_resp(chan, &skb2) > 0) 
			pcbit_l2_write(dev, MSG_TDATA_RESP, refnum, 
				       skb2, skb2->len);
		return;
		break;  
	case MSG_TDATA_CONF:
		if (!(chan = capi_channel(dev, skb))) {
			printk(KERN_WARNING 
			       "CAPI header: unknown channel id\n");
			break;
		}

#ifdef DEBUG
		if ( (*((ushort *) (skb->data + 2) )) != 0) {
                        printk(KERN_DEBUG "TDATA_CONF error\n");
		}
#endif
#ifdef BLOCK_TIMER
                if (chan->queued == MAX_QUEUED) {
                        del_timer(&chan->block_timer);
			chan->block_timer.function = NULL;
		}
                
#endif		
		chan->queued--;

		ictl.driver = dev->id;
		ictl.command = ISDN_STAT_BSENT;
		ictl.arg = chan->id;
		dev->dev_if->statcallb(&ictl);
		break;

	case MSG_CONN_IND:
		/*
		 *  channel: 1st not used will do
		 *           if both are used we're in trouble 
		 */

		if (!dev->b1->fsm_state)
			chan = dev->b1;
		else if (!dev->b2->fsm_state)
			chan = dev->b2;
		else {
			printk(KERN_INFO 
			       "Incoming connection: no channels available");