drivers/isdn/gigaset/i4l.c - linux/kernel/git/torvalds/linux - Git at Google

 /*
  * Stuff used by all variants of the driver
  *
  * Copyright (c) 2001 by Stefan Eilers,
  *                       Hansjoerg Lipp <hjlipp@web.de>,
  *                       Tilman Schmidt <tilman@imap.cc>.
  *
  * =====================================================================
  *	This program is free software; you can redistribute it and/or
  *	modify it under the terms of the GNU General Public License as
  *	published by the Free Software Foundation; either version 2 of
  *	the License, or (at your option) any later version.
  * =====================================================================
  */

 #include "gigaset.h"

 /* == Handling of I4L IO =====================================================*/

 /* writebuf_from_LL
  * called by LL to transmit data on an open channel
  * inserts the buffer data into the send queue and starts the transmission
  * Note that this operation must not sleep!
  * When the buffer is processed completely, gigaset_skb_sent() should be called.
  * parameters:
  *	driverID	driver ID as assigned by LL
  *	channel		channel number
  *	ack		if != 0 LL wants to be notified on completion via
  *			statcallb(ISDN_STAT_BSENT)
  *	skb		skb containing data to send
  * return value:
  *	number of accepted bytes
  *	0 if temporarily unable to accept data (out of buffer space)
  *	<0 on error (eg. -EINVAL)
  */
 static int writebuf_from_LL(int driverID, int channel, int ack,
 			    struct sk_buff *skb)
 {
 	struct cardstate *cs;
 	struct bc_state *bcs;
 	unsigned len;
 	unsigned skblen;

 	if (!(cs = gigaset_get_cs_by_id(driverID))) {
 		pr_err("%s: invalid driver ID (%d)\n", __func__, driverID);
 		return -ENODEV;
 	}
 	if (channel < 0 || channel >= cs->channels) {
 		dev_err(cs->dev, "%s: invalid channel ID (%d)\n",
 			__func__, channel);
 		return -ENODEV;
 	}
 	bcs = &cs->bcs[channel];
 	len = skb->len;

 	gig_dbg(DEBUG_LLDATA,
 		"Receiving data from LL (id: %d, ch: %d, ack: %d, sz: %d)",
 		driverID, channel, ack, len);

 	if (!len) {
 		if (ack)
 			dev_notice(cs->dev, "%s: not ACKing empty packet\n",
 				   __func__);
 		return 0;
 	}
 	if (len > MAX_BUF_SIZE) {
 		dev_err(cs->dev, "%s: packet too large (%d bytes)\n",
 			__func__, len);
 		return -EINVAL;
 	}

 	skblen = ack ? len : 0;
 	skb->head[0] = skblen & 0xff;
 	skb->head[1] = skblen >> 8;
 	gig_dbg(DEBUG_MCMD, "skb: len=%u, skblen=%u: %02x %02x",
 		len, skblen, (unsigned) skb->head[0], (unsigned) skb->head[1]);

 	/* pass to device-specific module */
 	return cs->ops->send_skb(bcs, skb);
 }

 void gigaset_skb_sent(struct bc_state *bcs, struct sk_buff *skb)
 {
 	unsigned len;
 	isdn_ctrl response;

 	++bcs->trans_up;

 	if (skb->len)
 		dev_warn(bcs->cs->dev, "%s: skb->len==%d\n",
 			 __func__, skb->len);

 	len = (unsigned char) skb->head[0] |
 	      (unsigned) (unsigned char) skb->head[1] << 8;
 	if (len) {
 		gig_dbg(DEBUG_MCMD, "ACKing to LL (id: %d, ch: %d, sz: %u)",
 			bcs->cs->myid, bcs->channel, len);

 		response.driver = bcs->cs->myid;
 		response.command = ISDN_STAT_BSENT;
 		response.arg = bcs->channel;
 		response.parm.length = len;
 		bcs->cs->iif.statcallb(&response);
 	}
 }
 EXPORT_SYMBOL_GPL(gigaset_skb_sent);

 /* This function will be called by LL to send commands
  * NOTE: LL ignores the returned value, for commands other than ISDN_CMD_IOCTL,
  * so don't put too much effort into it.
  */
 static int command_from_LL(isdn_ctrl *cntrl)
 {
 	struct cardstate *cs = gigaset_get_cs_by_id(cntrl->driver);
 	struct bc_state *bcs;
 	int retval = 0;
 	struct setup_parm *sp;

 	gigaset_debugdrivers();

 	if (!cs) {
 		pr_err("%s: invalid driver ID (%d)\n", __func__, cntrl->driver);
 		return -ENODEV;
 	}

 	switch (cntrl->command) {
 	case ISDN_CMD_IOCTL:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_IOCTL (driver: %d, arg: %ld)",
 			cntrl->driver, cntrl->arg);

 		dev_warn(cs->dev, "ISDN_CMD_IOCTL not supported\n");
 		return -EINVAL;

 	case ISDN_CMD_DIAL:
 		gig_dbg(DEBUG_ANY,
 			"ISDN_CMD_DIAL (driver: %d, ch: %ld, "
 			"phone: %s, ownmsn: %s, si1: %d, si2: %d)",
 			cntrl->driver, cntrl->arg,
 			cntrl->parm.setup.phone, cntrl->parm.setup.eazmsn,
 			cntrl->parm.setup.si1, cntrl->parm.setup.si2);

 		if (cntrl->arg >= cs->channels) {
 			dev_err(cs->dev,
 				"ISDN_CMD_DIAL: invalid channel (%d)\n",
 				(int) cntrl->arg);
 			return -EINVAL;
 		}

 		bcs = cs->bcs + cntrl->arg;

 		if (!gigaset_get_channel(bcs)) {
 			dev_err(cs->dev, "ISDN_CMD_DIAL: channel not free\n");
 			return -EBUSY;
 		}

 		sp = kmalloc(sizeof *sp, GFP_ATOMIC);
 		if (!sp) {
 			gigaset_free_channel(bcs);
 			dev_err(cs->dev, "ISDN_CMD_DIAL: out of memory\n");
 			return -ENOMEM;
 		}
 		*sp = cntrl->parm.setup;

 		if (!gigaset_add_event(cs, &bcs->at_state, EV_DIAL, sp,
 				       bcs->at_state.seq_index, NULL)) {
 			//FIXME what should we do?
 			kfree(sp);
 			gigaset_free_channel(bcs);
 			return -ENOMEM;
 		}

 		gig_dbg(DEBUG_CMD, "scheduling DIAL");
 		gigaset_schedule_event(cs);
 		break;
 	case ISDN_CMD_ACCEPTD: //FIXME
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_ACCEPTD");

 		if (cntrl->arg >= cs->channels) {
 			dev_err(cs->dev,
 				"ISDN_CMD_ACCEPTD: invalid channel (%d)\n",
 				(int) cntrl->arg);
 			return -EINVAL;
 		}

 		if (!gigaset_add_event(cs, &cs->bcs[cntrl->arg].at_state,
 				       EV_ACCEPT, NULL, 0, NULL)) {
 			//FIXME what should we do?
 			return -ENOMEM;
 		}

 		gig_dbg(DEBUG_CMD, "scheduling ACCEPT");
 		gigaset_schedule_event(cs);

 		break;
 	case ISDN_CMD_ACCEPTB:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_ACCEPTB");
 		break;
 	case ISDN_CMD_HANGUP:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_HANGUP (ch: %d)",
 			(int) cntrl->arg);

 		if (cntrl->arg >= cs->channels) {
 			dev_err(cs->dev,
 				"ISDN_CMD_HANGUP: invalid channel (%d)\n",
 				(int) cntrl->arg);
 			return -EINVAL;
 		}

 		if (!gigaset_add_event(cs, &cs->bcs[cntrl->arg].at_state,
 				       EV_HUP, NULL, 0, NULL)) {
 			//FIXME what should we do?
 			return -ENOMEM;
 		}

 		gig_dbg(DEBUG_CMD, "scheduling HUP");
 		gigaset_schedule_event(cs);

 		break;
 	case ISDN_CMD_CLREAZ: /* Do not signal incoming signals */ //FIXME
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_CLREAZ");
 		break;
 	case ISDN_CMD_SETEAZ: /* Signal incoming calls for given MSN */ //FIXME
 		gig_dbg(DEBUG_ANY,
 			"ISDN_CMD_SETEAZ (id: %d, ch: %ld, number: %s)",
 			cntrl->driver, cntrl->arg, cntrl->parm.num);
 		break;
 	case ISDN_CMD_SETL2: /* Set L2 to given protocol */
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_SETL2 (ch: %ld, proto: %lx)",
 			cntrl->arg & 0xff, (cntrl->arg >> 8));

 		if ((cntrl->arg & 0xff) >= cs->channels) {
 			dev_err(cs->dev,
 				"ISDN_CMD_SETL2: invalid channel (%d)\n",
 				(int) cntrl->arg & 0xff);
 			return -EINVAL;
 		}

 		if (!gigaset_add_event(cs, &cs->bcs[cntrl->arg & 0xff].at_state,
 				       EV_PROTO_L2, NULL, cntrl->arg >> 8,
 				       NULL)) {
 			//FIXME what should we do?
 			return -ENOMEM;
 		}

 		gig_dbg(DEBUG_CMD, "scheduling PROTO_L2");
 		gigaset_schedule_event(cs);
 		break;
 	case ISDN_CMD_SETL3: /* Set L3 to given protocol */
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_SETL3 (ch: %ld, proto: %lx)",
 			cntrl->arg & 0xff, (cntrl->arg >> 8));

 		if ((cntrl->arg & 0xff) >= cs->channels) {
 			dev_err(cs->dev,
 				"ISDN_CMD_SETL3: invalid channel (%d)\n",
 				(int) cntrl->arg & 0xff);
 			return -EINVAL;
 		}

 		if (cntrl->arg >> 8 != ISDN_PROTO_L3_TRANS) {
 			dev_err(cs->dev,
 				"ISDN_CMD_SETL3: invalid protocol %lu\n",
 				cntrl->arg >> 8);
 			return -EINVAL;
 		}

 		break;
 	case ISDN_CMD_PROCEED:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_PROCEED"); //FIXME
 		break;
 	case ISDN_CMD_ALERT:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_ALERT"); //FIXME
 		if (cntrl->arg >= cs->channels) {
 			dev_err(cs->dev,
 				"ISDN_CMD_ALERT: invalid channel (%d)\n",
 				(int) cntrl->arg);
 			return -EINVAL;
 		}
 		//bcs = cs->bcs + cntrl->arg;
 		//bcs->proto2 = -1;
 		// FIXME
 		break;
 	case ISDN_CMD_REDIR:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_REDIR"); //FIXME
 		break;
 	case ISDN_CMD_PROT_IO:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_PROT_IO");
 		break;
 	case ISDN_CMD_FAXCMD:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_FAXCMD");
 		break;
 	case ISDN_CMD_GETL2:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_GETL2");
 		break;
 	case ISDN_CMD_GETL3:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_GETL3");
 		break;
 	case ISDN_CMD_GETEAZ:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_GETEAZ");
 		break;
 	case ISDN_CMD_SETSIL:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_SETSIL");
 		break;
 	case ISDN_CMD_GETSIL:
 		gig_dbg(DEBUG_ANY, "ISDN_CMD_GETSIL");
 		break;
 	default:
 		dev_err(cs->dev, "unknown command %d from LL\n",
 			cntrl->command);
 		return -EINVAL;
 	}

 	return retval;
 }

 void gigaset_i4l_cmd(struct cardstate *cs, int cmd)
 {
 	isdn_ctrl command;

 	command.driver = cs->myid;
 	command.command = cmd;
 	command.arg = 0;
 	cs->iif.statcallb(&command);
 }

 void gigaset_i4l_channel_cmd(struct bc_state *bcs, int cmd)
 {
 	isdn_ctrl command;

 	command.driver = bcs->cs->myid;
 	command.command = cmd;
 	command.arg = bcs->channel;
 	bcs->cs->iif.statcallb(&command);
 }

 int gigaset_isdn_setup_dial(struct at_state_t *at_state, void *data)
 {
 	struct bc_state *bcs = at_state->bcs;
 	unsigned proto;
 	const char *bc;
 	size_t length[AT_NUM];
 	size_t l;
 	int i;
 	struct setup_parm *sp = data;

 	switch (bcs->proto2) {
 	case ISDN_PROTO_L2_HDLC:
 		proto = 1; /* 0: Bitsynchron, 1: HDLC, 2: voice */
 		break;
 	case ISDN_PROTO_L2_TRANS:
 		proto = 2; /* 0: Bitsynchron, 1: HDLC, 2: voice */
 		break;
 	default:
 		dev_err(bcs->cs->dev, "%s: invalid L2 protocol: %u\n",
 			__func__, bcs->proto2);
 		return -EINVAL;
 	}

 	switch (sp->si1) {
 	case 1:		/* audio */
 		bc = "9090A3";	/* 3.1 kHz audio, A-law */
 		break;
 	case 7:		/* data */
 	default:	/* hope the app knows what it is doing */
 		bc = "8890";	/* unrestricted digital information */
 	}
 	//FIXME add missing si1 values from 1TR6, inspect si2, set HLC/LLC

 	length[AT_DIAL ] = 1 + strlen(sp->phone) + 1 + 1;
 	l = strlen(sp->eazmsn);
 	length[AT_MSN  ] = l ? 6 + l + 1 + 1 : 0;
 	length[AT_BC   ] = 5 + strlen(bc) + 1 + 1;
 	length[AT_PROTO] = 6 + 1 + 1 + 1; /* proto: 1 character */
 	length[AT_ISO  ] = 6 + 1 + 1 + 1; /* channel: 1 character */
 	length[AT_TYPE ] = 6 + 1 + 1 + 1; /* call type: 1 character */
 	length[AT_HLC  ] = 0;

 	for (i = 0; i < AT_NUM; ++i) {
 		kfree(bcs->commands[i]);
 		bcs->commands[i] = NULL;
 		if (length[i] &&
 		    !(bcs->commands[i] = kmalloc(length[i], GFP_ATOMIC))) {
 			dev_err(bcs->cs->dev, "out of memory\n");
 			return -ENOMEM;
 		}
 	}

 	/* type = 1: extern, 0: intern, 2: recall, 3: door, 4: centrex */
 	if (sp->phone[0] == '*' && sp->phone[1] == '*') {
 		/* internal call: translate ** prefix to CTP value */
 		snprintf(bcs->commands[AT_DIAL], length[AT_DIAL],
 			 "D%s\r", sp->phone+2);
 		strncpy(bcs->commands[AT_TYPE], "^SCTP=0\r", length[AT_TYPE]);
 	} else {
 		snprintf(bcs->commands[AT_DIAL], length[AT_DIAL],
 			 "D%s\r", sp->phone);
 		strncpy(bcs->commands[AT_TYPE], "^SCTP=1\r", length[AT_TYPE]);
 	}

 	if (bcs->commands[AT_MSN])
 		snprintf(bcs->commands[AT_MSN], length[AT_MSN],
 			 "^SMSN=%s\r", sp->eazmsn);
 	snprintf(bcs->commands[AT_BC   ], length[AT_BC   ],
 		 "^SBC=%s\r", bc);
 	snprintf(bcs->commands[AT_PROTO], length[AT_PROTO],
 		 "^SBPR=%u\r", proto);
 	snprintf(bcs->commands[AT_ISO  ], length[AT_ISO  ],
 		 "^SISO=%u\r", (unsigned)bcs->channel + 1);

 	return 0;
 }

 int gigaset_isdn_setup_accept(struct at_state_t *at_state)
 {
 	unsigned proto;
 	size_t length[AT_NUM];
 	int i;
 	struct bc_state *bcs = at_state->bcs;

 	switch (bcs->proto2) {
 	case ISDN_PROTO_L2_HDLC:
 		proto = 1; /* 0: Bitsynchron, 1: HDLC, 2: voice */
 		break;
 	case ISDN_PROTO_L2_TRANS:
 		proto = 2; /* 0: Bitsynchron, 1: HDLC, 2: voice */
 		break;
 	default:
 		dev_err(at_state->cs->dev, "%s: invalid protocol: %u\n",
 			__func__, bcs->proto2);
 		return -EINVAL;
 	}

 	length[AT_DIAL ] = 0;
 	length[AT_MSN  ] = 0;
 	length[AT_BC   ] = 0;
 	length[AT_PROTO] = 6 + 1 + 1 + 1; /* proto: 1 character */
 	length[AT_ISO  ] = 6 + 1 + 1 + 1; /* channel: 1 character */
 	length[AT_TYPE ] = 0;
 	length[AT_HLC  ] = 0;

 	for (i = 0; i < AT_NUM; ++i) {
 		kfree(bcs->commands[i]);
 		bcs->commands[i] = NULL;
 		if (length[i] &&
 		    !(bcs->commands[i] = kmalloc(length[i], GFP_ATOMIC))) {
 			dev_err(at_state->cs->dev, "out of memory\n");
 			return -ENOMEM;
 		}
 	}

 	snprintf(bcs->commands[AT_PROTO], length[AT_PROTO],
 		 "^SBPR=%u\r", proto);
 	snprintf(bcs->commands[AT_ISO  ], length[AT_ISO  ],
 		 "^SISO=%u\r", (unsigned) bcs->channel + 1);

 	return 0;
 }

 int gigaset_isdn_icall(struct at_state_t *at_state)
 {
 	struct cardstate *cs = at_state->cs;
 	struct bc_state *bcs = at_state->bcs;
 	isdn_ctrl response;
 	int retval;

 	/* fill ICALL structure */
 	response.parm.setup.si1 = 0;	/* default: unknown */
 	response.parm.setup.si2 = 0;
 	response.parm.setup.screen = 0;	//FIXME how to set these?
 	response.parm.setup.plan = 0;
 	if (!at_state->str_var[STR_ZBC]) {
 		/* no BC (internal call): assume speech, A-law */
 		response.parm.setup.si1 = 1;
 	} else if (!strcmp(at_state->str_var[STR_ZBC], "8890")) {
 		/* unrestricted digital information */
 		response.parm.setup.si1 = 7;
 	} else if (!strcmp(at_state->str_var[STR_ZBC], "8090A3")) {
 		/* speech, A-law */
 		response.parm.setup.si1 = 1;
 	} else if (!strcmp(at_state->str_var[STR_ZBC], "9090A3")) {
 		/* 3,1 kHz audio, A-law */
 		response.parm.setup.si1 = 1;
 		response.parm.setup.si2 = 2;
 	} else {
 		dev_warn(cs->dev, "RING ignored - unsupported BC %s\n",
 		     at_state->str_var[STR_ZBC]);
 		return ICALL_IGNORE;
 	}
 	if (at_state->str_var[STR_NMBR]) {
 		strncpy(response.parm.setup.phone, at_state->str_var[STR_NMBR],
 			sizeof response.parm.setup.phone - 1);
 		response.parm.setup.phone[sizeof response.parm.setup.phone - 1] = 0;
 	} else
 		response.parm.setup.phone[0] = 0;
 	if (at_state->str_var[STR_ZCPN]) {
 		strncpy(response.parm.setup.eazmsn, at_state->str_var[STR_ZCPN],
 			sizeof response.parm.setup.eazmsn - 1);
 		response.parm.setup.eazmsn[sizeof response.parm.setup.eazmsn - 1] = 0;
 	} else
 		response.parm.setup.eazmsn[0] = 0;

 	if (!bcs) {
 		dev_notice(cs->dev, "no channel for incoming call\n");
 		response.command = ISDN_STAT_ICALLW;
 		response.arg = 0; //FIXME
 	} else {
 		gig_dbg(DEBUG_CMD, "Sending ICALL");
 		response.command = ISDN_STAT_ICALL;
 		response.arg = bcs->channel; //FIXME
 	}
 	response.driver = cs->myid;
 	retval = cs->iif.statcallb(&response);
 	gig_dbg(DEBUG_CMD, "Response: %d", retval);
 	switch (retval) {
 	case 0:	/* no takers */
 		return ICALL_IGNORE;
 	case 1:	/* alerting */
 		bcs->chstate |= CHS_NOTIFY_LL;
 		return ICALL_ACCEPT;
 	case 2:	/* reject */
 		return ICALL_REJECT;
 	case 3:	/* incomplete */
 		dev_warn(cs->dev,
 		       "LL requested unsupported feature: Incomplete Number\n");
 		return ICALL_IGNORE;
 	case 4:	/* proceeding */
 		/* Gigaset will send ALERTING anyway.
 		 * There doesn't seem to be a way to avoid this.
 		 */
 		return ICALL_ACCEPT;
 	case 5:	/* deflect */
 		dev_warn(cs->dev,
 			 "LL requested unsupported feature: Call Deflection\n");
 		return ICALL_IGNORE;
 	default:
 		dev_err(cs->dev, "LL error %d on ICALL\n", retval);
 		return ICALL_IGNORE;
 	}
 }

 /* Set Callback function pointer */
 int gigaset_register_to_LL(struct cardstate *cs, const char *isdnid)
 {
 	isdn_if *iif = &cs->iif;

 	gig_dbg(DEBUG_ANY, "Register driver capabilities to LL");

 	//iif->id[sizeof(iif->id) - 1]=0;
 	//strncpy(iif->id, isdnid, sizeof(iif->id) - 1);
 	if (snprintf(iif->id, sizeof iif->id, "%s_%u", isdnid, cs->minor_index)
 	    >= sizeof iif->id)
 		return -ENOMEM; //FIXME EINVAL/...??

 	iif->owner = THIS_MODULE;
 	iif->channels = cs->channels;
 	iif->maxbufsize = MAX_BUF_SIZE;
 	iif->features = ISDN_FEATURE_L2_TRANS |
 		ISDN_FEATURE_L2_HDLC |
 #ifdef GIG_X75
 		ISDN_FEATURE_L2_X75I |
 #endif
 		ISDN_FEATURE_L3_TRANS |
 		ISDN_FEATURE_P_EURO;
 	iif->hl_hdrlen = HW_HDR_LEN;		/* Area for storing ack */
 	iif->command = command_from_LL;
 	iif->writebuf_skb = writebuf_from_LL;
 	iif->writecmd = NULL;			/* Don't support isdnctrl */
 	iif->readstat = NULL;			/* Don't support isdnctrl */
 	iif->rcvcallb_skb = NULL;		/* Will be set by LL */
 	iif->statcallb = NULL;			/* Will be set by LL */

 	if (!register_isdn(iif))
 		return 0;

 	cs->myid = iif->channels;		/* Set my device id */
 	return 1;
 }
	/*
	* Stuff used by all variants of the driver
	*
	* Copyright (c) 2001 by Stefan Eilers,
	* Hansjoerg Lipp <hjlipp@web.de>,
	* Tilman Schmidt <tilman@imap.cc>.
	*
	* =====================================================================
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License as
	* published by the Free Software Foundation; either version 2 of
	* the License, or (at your option) any later version.
	* =====================================================================
	*/

	#include "gigaset.h"

	/* == Handling of I4L IO =====================================================*/

	/* writebuf_from_LL
	* called by LL to transmit data on an open channel
	* inserts the buffer data into the send queue and starts the transmission
	* Note that this operation must not sleep!
	* When the buffer is processed completely, gigaset_skb_sent() should be called.
	* parameters:
	* driverID driver ID as assigned by LL
	* channel channel number
	* ack if != 0 LL wants to be notified on completion via
	* statcallb(ISDN_STAT_BSENT)
	* skb skb containing data to send
	* return value:
	* number of accepted bytes
	* 0 if temporarily unable to accept data (out of buffer space)
	* <0 on error (eg. -EINVAL)
	*/
	static int writebuf_from_LL(int driverID, int channel, int ack,
	struct sk_buff *skb)
	{
	struct cardstate *cs;
	struct bc_state *bcs;
	unsigned len;
	unsigned skblen;

	if (!(cs = gigaset_get_cs_by_id(driverID))) {
	pr_err("%s: invalid driver ID (%d)\n", __func__, driverID);
	return -ENODEV;
	}
	if (channel < 0 \|\| channel >= cs->channels) {
	dev_err(cs->dev, "%s: invalid channel ID (%d)\n",
	__func__, channel);
	return -ENODEV;
	}
	bcs = &cs->bcs[channel];
	len = skb->len;

	gig_dbg(DEBUG_LLDATA,
	"Receiving data from LL (id: %d, ch: %d, ack: %d, sz: %d)",
	driverID, channel, ack, len);

	if (!len) {
	if (ack)
	dev_notice(cs->dev, "%s: not ACKing empty packet\n",
	__func__);
	return 0;
	}
	if (len > MAX_BUF_SIZE) {
	dev_err(cs->dev, "%s: packet too large (%d bytes)\n",
	__func__, len);
	return -EINVAL;
	}

	skblen = ack ? len : 0;
	skb->head[0] = skblen & 0xff;
	skb->head[1] = skblen >> 8;
	gig_dbg(DEBUG_MCMD, "skb: len=%u, skblen=%u: %02x %02x",
	len, skblen, (unsigned) skb->head[0], (unsigned) skb->head[1]);

	/* pass to device-specific module */
	return cs->ops->send_skb(bcs, skb);
	}

	void gigaset_skb_sent(struct bc_state bcs, struct sk_buff skb)
	{
	unsigned len;
	isdn_ctrl response;

	++bcs->trans_up;

	if (skb->len)
	dev_warn(bcs->cs->dev, "%s: skb->len==%d\n",
	__func__, skb->len);

	len = (unsigned char) skb->head[0] \|
	(unsigned) (unsigned char) skb->head[1] << 8;
	if (len) {
	gig_dbg(DEBUG_MCMD, "ACKing to LL (id: %d, ch: %d, sz: %u)",
	bcs->cs->myid, bcs->channel, len);

	response.driver = bcs->cs->myid;
	response.command = ISDN_STAT_BSENT;
	response.arg = bcs->channel;
	response.parm.length = len;
	bcs->cs->iif.statcallb(&response);
	}
	}
	EXPORT_SYMBOL_GPL(gigaset_skb_sent);

	/* This function will be called by LL to send commands
	* NOTE: LL ignores the returned value, for commands other than ISDN_CMD_IOCTL,
	* so don't put too much effort into it.
	*/
	static int command_from_LL(isdn_ctrl *cntrl)
	{
	struct cardstate *cs = gigaset_get_cs_by_id(cntrl->driver);
	struct bc_state *bcs;
	int retval = 0;
	struct setup_parm *sp;

	gigaset_debugdrivers();

	if (!cs) {
	pr_err("%s: invalid driver ID (%d)\n", __func__, cntrl->driver);
	return -ENODEV;
	}

	switch (cntrl->command) {
	case ISDN_CMD_IOCTL:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_IOCTL (driver: %d, arg: %ld)",
	cntrl->driver, cntrl->arg);

	dev_warn(cs->dev, "ISDN_CMD_IOCTL not supported\n");
	return -EINVAL;

	case ISDN_CMD_DIAL:
	gig_dbg(DEBUG_ANY,
	"ISDN_CMD_DIAL (driver: %d, ch: %ld, "
	"phone: %s, ownmsn: %s, si1: %d, si2: %d)",
	cntrl->driver, cntrl->arg,
	cntrl->parm.setup.phone, cntrl->parm.setup.eazmsn,
	cntrl->parm.setup.si1, cntrl->parm.setup.si2);

	if (cntrl->arg >= cs->channels) {
	dev_err(cs->dev,
	"ISDN_CMD_DIAL: invalid channel (%d)\n",
	(int) cntrl->arg);
	return -EINVAL;
	}

	bcs = cs->bcs + cntrl->arg;

	if (!gigaset_get_channel(bcs)) {
	dev_err(cs->dev, "ISDN_CMD_DIAL: channel not free\n");
	return -EBUSY;
	}

	sp = kmalloc(sizeof *sp, GFP_ATOMIC);
	if (!sp) {
	gigaset_free_channel(bcs);
	dev_err(cs->dev, "ISDN_CMD_DIAL: out of memory\n");
	return -ENOMEM;
	}
	*sp = cntrl->parm.setup;

	if (!gigaset_add_event(cs, &bcs->at_state, EV_DIAL, sp,
	bcs->at_state.seq_index, NULL)) {
	//FIXME what should we do?
	kfree(sp);
	gigaset_free_channel(bcs);
	return -ENOMEM;
	}

	gig_dbg(DEBUG_CMD, "scheduling DIAL");
	gigaset_schedule_event(cs);
	break;
	case ISDN_CMD_ACCEPTD: //FIXME
	gig_dbg(DEBUG_ANY, "ISDN_CMD_ACCEPTD");

	if (cntrl->arg >= cs->channels) {
	dev_err(cs->dev,
	"ISDN_CMD_ACCEPTD: invalid channel (%d)\n",
	(int) cntrl->arg);
	return -EINVAL;
	}

	if (!gigaset_add_event(cs, &cs->bcs[cntrl->arg].at_state,
	EV_ACCEPT, NULL, 0, NULL)) {
	//FIXME what should we do?
	return -ENOMEM;
	}

	gig_dbg(DEBUG_CMD, "scheduling ACCEPT");
	gigaset_schedule_event(cs);

	break;
	case ISDN_CMD_ACCEPTB:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_ACCEPTB");
	break;
	case ISDN_CMD_HANGUP:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_HANGUP (ch: %d)",
	(int) cntrl->arg);

	if (cntrl->arg >= cs->channels) {
	dev_err(cs->dev,
	"ISDN_CMD_HANGUP: invalid channel (%d)\n",
	(int) cntrl->arg);
	return -EINVAL;
	}

	if (!gigaset_add_event(cs, &cs->bcs[cntrl->arg].at_state,
	EV_HUP, NULL, 0, NULL)) {
	//FIXME what should we do?
	return -ENOMEM;
	}

	gig_dbg(DEBUG_CMD, "scheduling HUP");
	gigaset_schedule_event(cs);

	break;
	case ISDN_CMD_CLREAZ: /* Do not signal incoming signals */ //FIXME
	gig_dbg(DEBUG_ANY, "ISDN_CMD_CLREAZ");
	break;
	case ISDN_CMD_SETEAZ: /* Signal incoming calls for given MSN */ //FIXME
	gig_dbg(DEBUG_ANY,
	"ISDN_CMD_SETEAZ (id: %d, ch: %ld, number: %s)",
	cntrl->driver, cntrl->arg, cntrl->parm.num);
	break;
	case ISDN_CMD_SETL2: /* Set L2 to given protocol */
	gig_dbg(DEBUG_ANY, "ISDN_CMD_SETL2 (ch: %ld, proto: %lx)",
	cntrl->arg & 0xff, (cntrl->arg >> 8));

	if ((cntrl->arg & 0xff) >= cs->channels) {
	dev_err(cs->dev,
	"ISDN_CMD_SETL2: invalid channel (%d)\n",
	(int) cntrl->arg & 0xff);
	return -EINVAL;
	}

	if (!gigaset_add_event(cs, &cs->bcs[cntrl->arg & 0xff].at_state,
	EV_PROTO_L2, NULL, cntrl->arg >> 8,
	NULL)) {
	//FIXME what should we do?
	return -ENOMEM;
	}

	gig_dbg(DEBUG_CMD, "scheduling PROTO_L2");
	gigaset_schedule_event(cs);
	break;
	case ISDN_CMD_SETL3: /* Set L3 to given protocol */
	gig_dbg(DEBUG_ANY, "ISDN_CMD_SETL3 (ch: %ld, proto: %lx)",
	cntrl->arg & 0xff, (cntrl->arg >> 8));

	if ((cntrl->arg & 0xff) >= cs->channels) {
	dev_err(cs->dev,
	"ISDN_CMD_SETL3: invalid channel (%d)\n",
	(int) cntrl->arg & 0xff);
	return -EINVAL;
	}

	if (cntrl->arg >> 8 != ISDN_PROTO_L3_TRANS) {
	dev_err(cs->dev,
	"ISDN_CMD_SETL3: invalid protocol %lu\n",
	cntrl->arg >> 8);
	return -EINVAL;
	}

	break;
	case ISDN_CMD_PROCEED:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_PROCEED"); //FIXME
	break;
	case ISDN_CMD_ALERT:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_ALERT"); //FIXME
	if (cntrl->arg >= cs->channels) {
	dev_err(cs->dev,
	"ISDN_CMD_ALERT: invalid channel (%d)\n",
	(int) cntrl->arg);
	return -EINVAL;
	}
	//bcs = cs->bcs + cntrl->arg;
	//bcs->proto2 = -1;
	// FIXME
	break;
	case ISDN_CMD_REDIR:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_REDIR"); //FIXME
	break;
	case ISDN_CMD_PROT_IO:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_PROT_IO");
	break;
	case ISDN_CMD_FAXCMD:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_FAXCMD");
	break;
	case ISDN_CMD_GETL2:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_GETL2");
	break;
	case ISDN_CMD_GETL3:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_GETL3");
	break;
	case ISDN_CMD_GETEAZ:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_GETEAZ");
	break;
	case ISDN_CMD_SETSIL:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_SETSIL");
	break;
	case ISDN_CMD_GETSIL:
	gig_dbg(DEBUG_ANY, "ISDN_CMD_GETSIL");
	break;
	default:
	dev_err(cs->dev, "unknown command %d from LL\n",
	cntrl->command);
	return -EINVAL;
	}

	return retval;
	}

	void gigaset_i4l_cmd(struct cardstate *cs, int cmd)
	{
	isdn_ctrl command;

	command.driver = cs->myid;
	command.command = cmd;
	command.arg = 0;
	cs->iif.statcallb(&command);
	}

	void gigaset_i4l_channel_cmd(struct bc_state *bcs, int cmd)
	{
	isdn_ctrl command;

	command.driver = bcs->cs->myid;
	command.command = cmd;
	command.arg = bcs->channel;
	bcs->cs->iif.statcallb(&command);
	}

	int gigaset_isdn_setup_dial(struct at_state_t at_state, void data)
	{
	struct bc_state *bcs = at_state->bcs;
	unsigned proto;
	const char *bc;
	size_t length[AT_NUM];
	size_t l;
	int i;
	struct setup_parm *sp = data;

	switch (bcs->proto2) {
	case ISDN_PROTO_L2_HDLC:
	proto = 1; /* 0: Bitsynchron, 1: HDLC, 2: voice */
	break;
	case ISDN_PROTO_L2_TRANS:
	proto = 2; /* 0: Bitsynchron, 1: HDLC, 2: voice */
	break;
	default:
	dev_err(bcs->cs->dev, "%s: invalid L2 protocol: %u\n",
	__func__, bcs->proto2);
	return -EINVAL;
	}

	switch (sp->si1) {
	case 1: /* audio */
	bc = "9090A3"; /* 3.1 kHz audio, A-law */
	break;
	case 7: /* data */
	default: /* hope the app knows what it is doing */
	bc = "8890"; /* unrestricted digital information */
	}
	//FIXME add missing si1 values from 1TR6, inspect si2, set HLC/LLC

	length[AT_DIAL ] = 1 + strlen(sp->phone) + 1 + 1;
	l = strlen(sp->eazmsn);
	length[AT_MSN ] = l ? 6 + l + 1 + 1 : 0;
	length[AT_BC ] = 5 + strlen(bc) + 1 + 1;
	length[AT_PROTO] = 6 + 1 + 1 + 1; /* proto: 1 character */
	length[AT_ISO ] = 6 + 1 + 1 + 1; /* channel: 1 character */
	length[AT_TYPE ] = 6 + 1 + 1 + 1; /* call type: 1 character */
	length[AT_HLC ] = 0;

	for (i = 0; i < AT_NUM; ++i) {
	kfree(bcs->commands[i]);
	bcs->commands[i] = NULL;
	if (length[i] &&
	!(bcs->commands[i] = kmalloc(length[i], GFP_ATOMIC))) {
	dev_err(bcs->cs->dev, "out of memory\n");
	return -ENOMEM;
	}
	}

	/* type = 1: extern, 0: intern, 2: recall, 3: door, 4: centrex */
	if (sp->phone[0] == '' && sp->phone[1] == '') {
	/* internal call: translate ** prefix to CTP value */
	snprintf(bcs->commands[AT_DIAL], length[AT_DIAL],
	"D%s\r", sp->phone+2);
	strncpy(bcs->commands[AT_TYPE], "^SCTP=0\r", length[AT_TYPE]);
	} else {
	snprintf(bcs->commands[AT_DIAL], length[AT_DIAL],
	"D%s\r", sp->phone);
	strncpy(bcs->commands[AT_TYPE], "^SCTP=1\r", length[AT_TYPE]);
	}

	if (bcs->commands[AT_MSN])
	snprintf(bcs->commands[AT_MSN], length[AT_MSN],
	"^SMSN=%s\r", sp->eazmsn);
	snprintf(bcs->commands[AT_BC ], length[AT_BC ],
	"^SBC=%s\r", bc);
	snprintf(bcs->commands[AT_PROTO], length[AT_PROTO],
	"^SBPR=%u\r", proto);
	snprintf(bcs->commands[AT_ISO ], length[AT_ISO ],
	"^SISO=%u\r", (unsigned)bcs->channel + 1);

	return 0;
	}

	int gigaset_isdn_setup_accept(struct at_state_t *at_state)
	{
	unsigned proto;
	size_t length[AT_NUM];
	int i;
	struct bc_state *bcs = at_state->bcs;

	switch (bcs->proto2) {
	case ISDN_PROTO_L2_HDLC:
	proto = 1; /* 0: Bitsynchron, 1: HDLC, 2: voice */
	break;
	case ISDN_PROTO_L2_TRANS:
	proto = 2; /* 0: Bitsynchron, 1: HDLC, 2: voice */
	break;
	default:
	dev_err(at_state->cs->dev, "%s: invalid protocol: %u\n",
	__func__, bcs->proto2);
	return -EINVAL;
	}

	length[AT_DIAL ] = 0;
	length[AT_MSN ] = 0;
	length[AT_BC ] = 0;
	length[AT_PROTO] = 6 + 1 + 1 + 1; /* proto: 1 character */
	length[AT_ISO ] = 6 + 1 + 1 + 1; /* channel: 1 character */
	length[AT_TYPE ] = 0;
	length[AT_HLC ] = 0;

	for (i = 0; i < AT_NUM; ++i) {
	kfree(bcs->commands[i]);
	bcs->commands[i] = NULL;
	if (length[i] &&
	!(bcs->commands[i] = kmalloc(length[i], GFP_ATOMIC))) {
	dev_err(at_state->cs->dev, "out of memory\n");
	return -ENOMEM;
	}
	}

	snprintf(bcs->commands[AT_PROTO], length[AT_PROTO],
	"^SBPR=%u\r", proto);
	snprintf(bcs->commands[AT_ISO ], length[AT_ISO ],
	"^SISO=%u\r", (unsigned) bcs->channel + 1);

	return 0;
	}

	int gigaset_isdn_icall(struct at_state_t *at_state)
	{
	struct cardstate *cs = at_state->cs;
	struct bc_state *bcs = at_state->bcs;
	isdn_ctrl response;
	int retval;

	/* fill ICALL structure */
	response.parm.setup.si1 = 0; /* default: unknown */
	response.parm.setup.si2 = 0;
	response.parm.setup.screen = 0; //FIXME how to set these?
	response.parm.setup.plan = 0;
	if (!at_state->str_var[STR_ZBC]) {
	/* no BC (internal call): assume speech, A-law */
	response.parm.setup.si1 = 1;
	} else if (!strcmp(at_state->str_var[STR_ZBC], "8890")) {
	/* unrestricted digital information */
	response.parm.setup.si1 = 7;
	} else if (!strcmp(at_state->str_var[STR_ZBC], "8090A3")) {
	/* speech, A-law */
	response.parm.setup.si1 = 1;
	} else if (!strcmp(at_state->str_var[STR_ZBC], "9090A3")) {
	/* 3,1 kHz audio, A-law */
	response.parm.setup.si1 = 1;
	response.parm.setup.si2 = 2;
	} else {
	dev_warn(cs->dev, "RING ignored - unsupported BC %s\n",
	at_state->str_var[STR_ZBC]);
	return ICALL_IGNORE;
	}
	if (at_state->str_var[STR_NMBR]) {
	strncpy(response.parm.setup.phone, at_state->str_var[STR_NMBR],
	sizeof response.parm.setup.phone - 1);
	response.parm.setup.phone[sizeof response.parm.setup.phone - 1] = 0;
	} else
	response.parm.setup.phone[0] = 0;
	if (at_state->str_var[STR_ZCPN]) {
	strncpy(response.parm.setup.eazmsn, at_state->str_var[STR_ZCPN],
	sizeof response.parm.setup.eazmsn - 1);
	response.parm.setup.eazmsn[sizeof response.parm.setup.eazmsn - 1] = 0;
	} else
	response.parm.setup.eazmsn[0] = 0;

	if (!bcs) {
	dev_notice(cs->dev, "no channel for incoming call\n");
	response.command = ISDN_STAT_ICALLW;
	response.arg = 0; //FIXME
	} else {
	gig_dbg(DEBUG_CMD, "Sending ICALL");
	response.command = ISDN_STAT_ICALL;
	response.arg = bcs->channel; //FIXME
	}
	response.driver = cs->myid;
	retval = cs->iif.statcallb(&response);
	gig_dbg(DEBUG_CMD, "Response: %d", retval);
	switch (retval) {
	case 0: /* no takers */
	return ICALL_IGNORE;
	case 1: /* alerting */
	bcs->chstate \|= CHS_NOTIFY_LL;
	return ICALL_ACCEPT;
	case 2: /* reject */
	return ICALL_REJECT;
	case 3: /* incomplete */
	dev_warn(cs->dev,
	"LL requested unsupported feature: Incomplete Number\n");
	return ICALL_IGNORE;
	case 4: /* proceeding */
	/* Gigaset will send ALERTING anyway.
	* There doesn't seem to be a way to avoid this.
	*/
	return ICALL_ACCEPT;
	case 5: /* deflect */
	dev_warn(cs->dev,
	"LL requested unsupported feature: Call Deflection\n");
	return ICALL_IGNORE;
	default:
	dev_err(cs->dev, "LL error %d on ICALL\n", retval);
	return ICALL_IGNORE;
	}
	}

	/* Set Callback function pointer */
	int gigaset_register_to_LL(struct cardstate cs, const char isdnid)
	{
	isdn_if *iif = &cs->iif;

	gig_dbg(DEBUG_ANY, "Register driver capabilities to LL");

	//iif->id[sizeof(iif->id) - 1]=0;
	//strncpy(iif->id, isdnid, sizeof(iif->id) - 1);
	if (snprintf(iif->id, sizeof iif->id, "%s_%u", isdnid, cs->minor_index)
	>= sizeof iif->id)
	return -ENOMEM; //FIXME EINVAL/...??

	iif->owner = THIS_MODULE;
	iif->channels = cs->channels;
	iif->maxbufsize = MAX_BUF_SIZE;
	iif->features = ISDN_FEATURE_L2_TRANS \|
	ISDN_FEATURE_L2_HDLC \|
	#ifdef GIG_X75
	ISDN_FEATURE_L2_X75I \|
	#endif
	ISDN_FEATURE_L3_TRANS \|
	ISDN_FEATURE_P_EURO;
	iif->hl_hdrlen = HW_HDR_LEN; /* Area for storing ack */
	iif->command = command_from_LL;
	iif->writebuf_skb = writebuf_from_LL;
	iif->writecmd = NULL; /* Don't support isdnctrl */
	iif->readstat = NULL; /* Don't support isdnctrl */
	iif->rcvcallb_skb = NULL; /* Will be set by LL */
	iif->statcallb = NULL; /* Will be set by LL */

	if (!register_isdn(iif))
	return 0;

	cs->myid = iif->channels; /* Set my device id */
	return 1;
	}