kcapi.c

linux-2.6.15.6

/* $Id: kcapi.c,v 1.1.2.8 2004/03/26 19:57:20 armin Exp $
 * 
 * Kernel CAPI 2.0 Module
 * 
 * Copyright 1999 by Carsten Paeth <[e-mail]>
 * Copyright 2002 by Kai Germaschewski <[e-mail]>
 * 
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 */

#define CONFIG_AVMB1_COMPAT

#include "kcapi.h"
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/skbuff.h>
#include <linux/workqueue.h>
#include <linux/capi.h>
#include <linux/kernelcapi.h>
#include <linux/init.h>
#include <linux/moduleparam.h>
#include <linux/delay.h>
#include <asm/uaccess.h>
#include <linux/isdn/capicmd.h>
#include <linux/isdn/capiutil.h>
#ifdef CONFIG_AVMB1_COMPAT
#include <linux/b1lli.h>
#endif

static char *revision = "$Revision: 1.1.2.8 $";

/* ------------------------------------------------------------- */

static int showcapimsgs = 0;

MODULE_DESCRIPTION("CAPI4Linux: kernel CAPI layer");
MODULE_AUTHOR("Carsten Paeth");
MODULE_LICENSE("GPL");
module_param(showcapimsgs, uint, 0);

/* ------------------------------------------------------------- */

struct capi_notifier {
	struct work_struct work;
	unsigned int cmd;
	u32 controller;
	u16 applid;
	u32 ncci;
};

/* ------------------------------------------------------------- */

static struct capi_version driver_version = {2, 0, 1, 1<<4};
static char driver_serial[CAPI_SERIAL_LEN] = "0004711";
static char capi_manufakturer[64] = "AVM Berlin";

#define NCCI2CTRL(ncci)    (((ncci) >> 24) & 0x7f)

LIST_HEAD(capi_drivers);
DEFINE_RWLOCK(capi_drivers_list_lock);

static DEFINE_RWLOCK(application_lock);
static DECLARE_MUTEX(controller_sem);

struct capi20_appl *capi_applications[CAPI_MAXAPPL];
struct capi_ctr *capi_cards[CAPI_MAXCONTR];

static int ncards;

/* -------- controller ref counting -------------------------------------- */

static inline struct capi_ctr *
capi_ctr_get(struct capi_ctr *card)
{
	if (!try_module_get(card->owner))
		return NULL;
	return card;
}

static inline void
capi_ctr_put(struct capi_ctr *card)
{
	module_put(card->owner);
}

/* ------------------------------------------------------------- */

static inline struct capi_ctr *get_capi_ctr_by_nr(u16 contr)
{
	if (contr - 1 >= CAPI_MAXCONTR)
		return NULL;

	return capi_cards[contr - 1];
}

static inline struct capi20_appl *get_capi_appl_by_nr(u16 applid)
{
	if (applid - 1 >= CAPI_MAXAPPL)
		return NULL;

	return capi_applications[applid - 1];
}

/* -------- util functions ------------------------------------ */

static inline int capi_cmd_valid(u8 cmd)
{
	switch (cmd) {
	case CAPI_ALERT:
	case CAPI_CONNECT:
	case CAPI_CONNECT_ACTIVE:
	case CAPI_CONNECT_B3_ACTIVE:
	case CAPI_CONNECT_B3:
	case CAPI_CONNECT_B3_T90_ACTIVE:
	case CAPI_DATA_B3:
	case CAPI_DISCONNECT_B3:
	case CAPI_DISCONNECT:
	case CAPI_FACILITY:
	case CAPI_INFO:
	case CAPI_LISTEN:
	case CAPI_MANUFACTURER:
	case CAPI_RESET_B3:
	case CAPI_SELECT_B_PROTOCOL:
		return 1;
	}
	return 0;
}

static inline int capi_subcmd_valid(u8 subcmd)
{
	switch (subcmd) {
	case CAPI_REQ:
	case CAPI_CONF:
	case CAPI_IND:
	case CAPI_RESP:
		return 1;
	}
	return 0;
}

/* ------------------------------------------------------------ */

static void register_appl(struct capi_ctr *card, u16 applid, capi_register_params *rparam)
{
	card = capi_ctr_get(card);

	if (card)
		card->register_appl(card, applid, rparam);
	else
		printk(KERN_WARNING "%s: cannot get card resources\n", __FUNCTION__);
}


static void release_appl(struct capi_ctr *card, u16 applid)
{
	DBG("applid %#x", applid);
	
	card->release_appl(card, applid);
	capi_ctr_put(card);
}

/* -------- KCI_CONTRUP --------------------------------------- */

static void notify_up(u32 contr)
{
	struct capi_ctr *card = get_capi_ctr_by_nr(contr);
	struct capi20_appl *ap;
	u16 applid;

	if (showcapimsgs & 1) {
	        printk(KERN_DEBUG "kcapi: notify up contr %d\n", contr);
	}
	if (!card) {
		printk(KERN_WARNING "%s: invalid contr %d\n", __FUNCTION__, contr);
		return;
	}
	for (applid = 1; applid <= CAPI_MAXAPPL; applid++) {
		ap = get_capi_appl_by_nr(applid);
		if (!ap || ap->release_in_progress) continue;
		register_appl(card, applid, &ap->rparam);
		if (ap->callback && !ap->release_in_progress)
			ap->callback(KCI_CONTRUP, contr, &card->profile);
	}
}

/* -------- KCI_CONTRDOWN ------------------------------------- */

static void notify_down(u32 contr)
{
	struct capi20_appl *ap;
	u16 applid;

	if (showcapimsgs & 1) {
        	printk(KERN_DEBUG "kcapi: notify down contr %d\n", contr);
	}

	for (applid = 1; applid <= CAPI_MAXAPPL; applid++) {
		ap = get_capi_appl_by_nr(applid);
		if (ap && ap->callback && !ap->release_in_progress)
			ap->callback(KCI_CONTRDOWN, contr, NULL);
	}
}

static void notify_handler(void *data)
{
	struct capi_notifier *np = data;

	switch (np->cmd) {
	case KCI_CONTRUP:
		notify_up(np->controller);
		break;
	case KCI_CONTRDOWN:
		notify_down(np->controller);
		break;
	}

	kfree(np);
}

/*
 * The notifier will result in adding/deleteing of devices. Devices can
 * only removed in user process, not in bh.
 */
static int notify_push(unsigned int cmd, u32 controller, u16 applid, u32 ncci)
{
	struct capi_notifier *np = kmalloc(sizeof(*np), GFP_ATOMIC);

	if (!np)
		return -ENOMEM;

	INIT_WORK(&np->work, notify_handler, np);
	np->cmd = cmd;
	np->controller = controller;
	np->applid = applid;
	np->ncci = ncci;

	schedule_work(&np->work);
	return 0;
}

	
/* -------- Receiver ------------------------------------------ */

static void recv_handler(void *_ap)
{
	struct sk_buff *skb;
	struct capi20_appl *ap = (struct capi20_appl *) _ap;

	if ((!ap) || (ap->release_in_progress))
		return;

	down(&ap->recv_sem);
	while ((skb = skb_dequeue(&ap->recv_queue))) {
		if (CAPIMSG_CMD(skb->data) == CAPI_DATA_B3_IND)
			ap->nrecvdatapkt++;
		else
			ap->nrecvctlpkt++;

		ap->recv_message(ap, skb);
	}
	up(&ap->recv_sem);
}

void capi_ctr_handle_message(struct capi_ctr * card, u16 appl, struct sk_buff *skb)
{
	struct capi20_appl *ap;
	int showctl = 0;
	u8 cmd, subcmd;
	unsigned long flags;

	if (card->cardstate != CARD_RUNNING) {
		printk(KERN_INFO "kcapi: controller %d not active, got: %s",
		       card->cnr, capi_message2str(skb->data));
		goto error;
	}

	cmd = CAPIMSG_COMMAND(skb->data);
        subcmd = CAPIMSG_SUBCOMMAND(skb->data);
	if (cmd == CAPI_DATA_B3 && subcmd == CAPI_IND) {
		card->nrecvdatapkt++;
	        if (card->traceflag > 2) showctl |= 2;
	} else {
		card->nrecvctlpkt++;
	        if (card->traceflag) showctl |= 2;
	}
	showctl |= (card->traceflag & 1);
	if (showctl & 2) {
		if (showctl & 1) {
			printk(KERN_DEBUG "kcapi: got [0x%lx] id#%d %s len=%u\n",
			       (unsigned long) card->cnr,
			       CAPIMSG_APPID(skb->data),
			       capi_cmd2str(cmd, subcmd),
			       CAPIMSG_LEN(skb->data));
		} else {
			printk(KERN_DEBUG "kcapi: got [0x%lx] %s\n",
					(unsigned long) card->cnr,
					capi_message2str(skb->data));
		}

	}

	read_lock_irqsave(&application_lock, flags);
	ap = get_capi_appl_by_nr(CAPIMSG_APPID(skb->data));
	if ((!ap) || (ap->release_in_progress)) {
		read_unlock_irqrestore(&application_lock, flags);
		printk(KERN_ERR "kcapi: handle_message: applid %d state released (%s)\n",
			CAPIMSG_APPID(skb->data), capi_message2str(skb->data));
		goto error;
	}
	skb_queue_tail(&ap->recv_queue, skb);
	schedule_work(&ap->recv_work);
	read_unlock_irqrestore(&application_lock, flags);

	return;

error:
	kfree_skb(skb);
}

EXPORT_SYMBOL(capi_ctr_handle_message);

void capi_ctr_ready(struct capi_ctr * card)
{
	card->cardstate = CARD_RUNNING;

        printk(KERN_NOTICE "kcapi: card %d \"%s\" ready.\n",
	       card->cnr, card->name);

	notify_push(KCI_CONTRUP, card->cnr, 0, 0);
}

EXPORT_SYMBOL(capi_ctr_ready);

void capi_ctr_reseted(struct capi_ctr * card)
{
	u16 appl;

	DBG("");

        if (card->cardstate == CARD_DETECTED)
		return;

        card->cardstate = CARD_DETECTED;

	memset(card->manu, 0, sizeof(card->manu));
	memset(&card->version, 0, sizeof(card->version));
	memset(&card->profile, 0, sizeof(card->profile));
	memset(card->serial, 0, sizeof(card->serial));

	for (appl = 1; appl <= CAPI_MAXAPPL; appl++) {
		struct capi20_appl *ap = get_capi_appl_by_nr(appl);
		if (!ap || ap->release_in_progress)
			continue;

		capi_ctr_put(card);
	}

	printk(KERN_NOTICE "kcapi: card %d down.\n", card->cnr);

	notify_push(KCI_CONTRDOWN, card->cnr, 0, 0);
}

EXPORT_SYMBOL(capi_ctr_reseted);

void capi_ctr_suspend_output(struct capi_ctr *card)
{
	if (!card->blocked) {
		printk(KERN_DEBUG "kcapi: card %d suspend\n", card->cnr);
		card->blocked = 1;
	}
}

EXPORT_SYMBOL(capi_ctr_suspend_output);

void capi_ctr_resume_output(struct capi_ctr *card)
{
	if (card->blocked) {
		printk(KERN_DEBUG "kcapi: card %d resume\n", card->cnr);
		card->blocked = 0;
	}
}

EXPORT_SYMBOL(capi_ctr_resume_output);

/* ------------------------------------------------------------- */

int
attach_capi_ctr(struct capi_ctr *card)
{
	int i;

	down(&controller_sem);

	for (i = 0; i < CAPI_MAXCONTR; i++) {
		if (capi_cards[i] == NULL)
			break;
	}
	if (i == CAPI_MAXCONTR) {
		up(&controller_sem);
		printk(KERN_ERR "kcapi: out of controller slots\n");
	   	return -EBUSY;
	}
	capi_cards[i] = card;

	up(&controller_sem);

	card->nrecvctlpkt = 0;
	card->nrecvdatapkt = 0;
	card->nsentctlpkt = 0;
	card->nsentdatapkt = 0;
	card->cnr = i + 1;
	card->cardstate = CARD_DETECTED;
	card->blocked = 0;
	card->traceflag = showcapimsgs;

	sprintf(card->procfn, "capi/controllers/%d", card->cnr);
	card->procent = create_proc_entry(card->procfn, 0, NULL);
	if (card->procent) {
	   card->procent->read_proc = 
		(int (*)(char *,char **,off_t,int,int *,void *))
			card->ctr_read_proc;
	   card->procent->data = card;
	}

	ncards++;
	printk(KERN_NOTICE "kcapi: Controller %d: %s attached\n",
			card->cnr, card->name);
	return 0;
}

EXPORT_SYMBOL(attach_capi_ctr);

int detach_capi_ctr(struct capi_ctr *card)
{
        if (card->cardstate != CARD_DETECTED)
		capi_ctr_reseted(card);

	ncards--;

	if (card->procent) {
	   remove_proc_entry(card->procfn, NULL);
	   card->procent = NULL;
	}
	capi_cards[card->cnr - 1] = NULL;
	printk(KERN_NOTICE "kcapi: Controller %d: %s unregistered\n",
			card->cnr, card->name);

	return 0;
}

EXPORT_SYMBOL(detach_capi_ctr);

void register_capi_driver(struct capi_driver *driver)
{
	unsigned long flags;

	write_lock_irqsave(&capi_drivers_list_lock, flags);
	list_add_tail(&driver->list, &capi_drivers);
	write_unlock_irqrestore(&capi_drivers_list_lock, flags);
}

EXPORT_SYMBOL(register_capi_driver);

void unregister_capi_driver(struct capi_driver *driver)
{
	unsigned long flags;

	write_lock_irqsave(&capi_drivers_list_lock, flags);
	list_del(&driver->list);
	write_unlock_irqrestore(&capi_drivers_list_lock, flags);
}

EXPORT_SYMBOL(unregister_capi_driver);

/* ------------------------------------------------------------- */
/* -------- CAPI2.0 Interface ---------------------------------- */
/* ------------------------------------------------------------- */

u16 capi20_isinstalled(void)
{
	int i;
	for (i = 0; i < CAPI_MAXCONTR; i++) {
		if (capi_cards[i] && capi_cards[i]->cardstate == CARD_RUNNING)
			return CAPI_NOERROR;
	}
	return CAPI_REGNOTINSTALLED;
}

EXPORT_SYMBOL(capi20_isinstalled);