[PATCH 4/9] isdn4linux: Siemens Gigaset drivers - isdn4linux interface

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From: Tilman Schmidt <[email protected]>, Hansjoerg Lipp <[email protected]>

This patch adds the isdn4linux subsystem interface to the gigaset module.
The isdn4linux subsystem interface handles requests from and notifications
to the isdn4linux subsystem.

Signed-off-by: Hansjoerg Lipp <[email protected]>
Signed-off-by: Tilman Schmidt <[email protected]>
---

 drivers/isdn/gigaset/i4l.c |  567 +++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 567 insertions(+)

--- linux-2.6.14/drivers/isdn/gigaset/i4l.c	1970-01-01 01:00:00.000000000 +0100
+++ linux-2.6.14-gig/drivers/isdn/gigaset/i4l.c	2005-12-11 13:21:42.000000000 +0100
@@ -0,0 +1,567 @@
+/*
+ * Stuff used by all variants of the driver
+ *
+ * Copyright (c) 2001 by Stefan Eilers ([email protected]),
+ *                       Hansjoerg Lipp ([email protected]),
+ *                       Tilman Schmidt ([email protected]).
+ *
+ * =====================================================================
+ *	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.
+ * =====================================================================
+ * ToDo: ...
+ * =====================================================================
+ * Version: $Id: i4l.c,v 1.3.2.8 2005/11/16 20:41:00 hjlipp Exp $
+ * =====================================================================
+ */
+
+#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))) {
+		err("%s: invalid driver ID (%d)", __func__, driverID);
+		return -ENODEV;
+	}
+	if (channel < 0 || channel >= cs->channels) {
+		err("%s: invalid channel ID (%d)", __func__, channel);
+		return -ENODEV;
+	}
+	bcs = &cs->bcs[channel];
+	len = skb->len;
+
+	dbg(DEBUG_LLDATA,
+	    "Receiving data from LL (id: %d, channel: %d, ack: %d, size: %d)",
+	    driverID, channel, ack, len);
+
+	if (!len) {
+		if (ack)
+			warn("not ACKing empty packet from LL");
+		return 0;
+	}
+	if (len > MAX_BUF_SIZE) {
+		err("%s: packet too large (%d bytes)", __func__, channel);
+		return -EINVAL;
+	}
+
+	if (!atomic_read(&cs->connected))
+		return -ENODEV;
+
+	skblen = ack ? len : 0;
+	skb->head[0] = skblen & 0xff;
+	skb->head[1] = skblen >> 8;
+	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)
+		warn("%s: skb->len==%d", __func__, skb->len);
+
+	len = (unsigned char) skb->head[0] |
+	      (unsigned) (unsigned char) skb->head[1] << 8;
+	if (len) {
+		dbg(DEBUG_MCMD,
+		    "Acknowledge sending to LL (id: %d, channel: %d size: %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);
+	//isdn_ctrl response;
+	//unsigned long flags;
+	struct bc_state *bcs;
+	int retval = 0;
+	struct setup_parm *sp;
+
+	//dbg(DEBUG_ANY, "Gigaset_HW: Receiving command");
+	gigaset_debugdrivers();
+
+	/* Terminate this call if no device is present. Bt if the command is "ISDN_CMD_LOCK" or
+	 * "ISDN_CMD_UNLOCK" then execute it due to the fact that they are device independent !
+	 */
+	//FIXME "remove test for &connected"
+	if ((!cs || !atomic_read(&cs->connected))) {
+		warn("LL tried to access unknown device with nr. %d",
+		     cntrl->driver);
+		return -ENODEV;
+	}
+
+	switch (cntrl->command) {
+	case ISDN_CMD_IOCTL:
+
+		dbg(DEBUG_ANY, "ISDN_CMD_IOCTL (driver:%d,arg: %ld)",
+		    cntrl->driver, cntrl->arg);
+
+		warn("ISDN_CMD_IOCTL is not supported.");
+		return -EINVAL;
+
+	case ISDN_CMD_DIAL:
+		dbg(DEBUG_ANY, "ISDN_CMD_DIAL (driver: %d, channel: %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) {
+			err("invalid channel (%d)", (int) cntrl->arg);
+			return -EINVAL;
+		}
+
+		bcs = cs->bcs + cntrl->arg;
+
+		if (!gigaset_get_channel(bcs)) {
+			err("channel not free");
+			return -EBUSY;
+		}
+
+		sp = kmalloc(sizeof *sp, GFP_ATOMIC);
+		if (!sp) {
+			gigaset_free_channel(bcs);
+			err("ISDN_CMD_DIAL: out of memory");
+			return -ENOMEM;
+		}
+		*sp = cntrl->parm.setup;
+
+		if (!gigaset_add_event(cs, &bcs->at_state, EV_DIAL, sp,
+			               atomic_read(&bcs->at_state.seq_index),
+			               NULL)) {
+			//FIXME what should we do?
+			kfree(sp);
+			gigaset_free_channel(bcs);
+			return -ENOMEM;
+		}
+
+		dbg(DEBUG_CMD, "scheduling DIAL");
+		gigaset_schedule_event(cs);
+		break;
+	case ISDN_CMD_ACCEPTD: //FIXME
+		dbg(DEBUG_ANY, "ISDN_CMD_ACCEPTD");
+
+		if (cntrl->arg >= cs->channels) {
+			err("invalid channel (%d)", (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;
+		}
+
+		dbg(DEBUG_CMD, "scheduling ACCEPT");
+		gigaset_schedule_event(cs);
+
+		break;
+	case ISDN_CMD_ACCEPTB:
+		dbg(DEBUG_ANY, "ISDN_CMD_ACCEPTB");
+		break;
+	case ISDN_CMD_HANGUP:
+		dbg(DEBUG_ANY,
+		    "ISDN_CMD_HANGUP (channel: %d)", (int) cntrl->arg);
+
+		if (cntrl->arg >= cs->channels) {
+			err("ISDN_CMD_HANGUP: invalid channel (%u)",
+			    (unsigned) 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;
+		}
+
+		dbg(DEBUG_CMD, "scheduling HUP");
+		gigaset_schedule_event(cs);
+
+		break;
+	case ISDN_CMD_CLREAZ:               /* Do not signal incoming signals */ //FIXME
+		dbg(DEBUG_ANY, "ISDN_CMD_CLREAZ");
+		break;
+	case ISDN_CMD_SETEAZ:               /* Signal incoming calls for given MSN */ //FIXME
+		dbg(DEBUG_ANY,
+		    "ISDN_CMD_SETEAZ (id:%d, channel: %ld, number: %s)",
+		    cntrl->driver, cntrl->arg, cntrl->parm.num);
+		break;
+	case ISDN_CMD_SETL2:                /* Set L2 to given protocol */
+		dbg(DEBUG_ANY, "ISDN_CMD_SETL2 (Channel: %ld, Proto: %lx)",
+		     cntrl->arg & 0xff, (cntrl->arg >> 8));
+
+		if ((cntrl->arg & 0xff) >= cs->channels) {
+			err("invalid channel (%u)",
+			    (unsigned) 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;
+		}
+
+		dbg(DEBUG_CMD, "scheduling PROTO_L2");
+		gigaset_schedule_event(cs);
+		break;
+	case ISDN_CMD_SETL3:              /* Set L3 to given protocol */
+		dbg(DEBUG_ANY, "ISDN_CMD_SETL3 (Channel: %ld, Proto: %lx)",
+		     cntrl->arg & 0xff, (cntrl->arg >> 8));
+
+		if ((cntrl->arg & 0xff) >= cs->channels) {
+			err("invalid channel (%u)",
+			    (unsigned) cntrl->arg & 0xff);
+			return -EINVAL;
+		}
+
+		if (cntrl->arg >> 8 != ISDN_PROTO_L3_TRANS) {
+			err("invalid protocol %lu", cntrl->arg >> 8);
+			return -EINVAL;
+		}
+
+		break;
+	case ISDN_CMD_PROCEED:
+		dbg(DEBUG_ANY, "ISDN_CMD_PROCEED"); //FIXME
+		break;
+	case ISDN_CMD_ALERT:
+		dbg(DEBUG_ANY, "ISDN_CMD_ALERT"); //FIXME
+		if (cntrl->arg >= cs->channels) {
+			err("invalid channel (%d)", (int) cntrl->arg);
+			return -EINVAL;
+		}
+		//bcs = cs->bcs + cntrl->arg;
+		//bcs->proto2 = -1;
+		// FIXME
+		break;
+	case ISDN_CMD_REDIR:
+		dbg(DEBUG_ANY, "ISDN_CMD_REDIR"); //FIXME
+		break;
+	case ISDN_CMD_PROT_IO:
+		dbg(DEBUG_ANY, "ISDN_CMD_PROT_IO");
+		break;
+	case ISDN_CMD_FAXCMD:
+		dbg(DEBUG_ANY, "ISDN_CMD_FAXCMD");
+		break;
+	case ISDN_CMD_GETL2:
+		dbg(DEBUG_ANY, "ISDN_CMD_GETL2");
+		break;
+	case ISDN_CMD_GETL3:
+		dbg(DEBUG_ANY, "ISDN_CMD_GETL3");
+		break;
+	case ISDN_CMD_GETEAZ:
+		dbg(DEBUG_ANY, "ISDN_CMD_GETEAZ");
+		break;
+	case ISDN_CMD_SETSIL:
+		dbg(DEBUG_ANY, "ISDN_CMD_SETSIL");
+		break;
+	case ISDN_CMD_GETSIL:
+		dbg(DEBUG_ANY, "ISDN_CMD_GETSIL");
+		break;
+	default:
+		err("unknown command %d from LL",
+		     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:
+		err("invalid protocol: %u", 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))) {
+			err("out of memory");
+			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:
+		err("invalid protocol: %u", 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))) {
+			err("out of memory");
+			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 {
+		warn("RING ignored - unsupported BC %s",
+		     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) {
+		notice("no channel for incoming call");
+		dbg(DEBUG_CMD, "Sending ICALLW");
+		response.command = ISDN_STAT_ICALLW;
+		response.arg = 0; //FIXME
+	} else {
+		dbg(DEBUG_CMD, "Sending ICALL");
+		response.command = ISDN_STAT_ICALL;
+		response.arg = bcs->channel; //FIXME
+	}
+	response.driver = cs->myid;
+	retval = cs->iif.statcallb(&response);
+	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 */
+		warn("LL requested unsupported feature: Incomplete Number");
+		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 */
+		warn("LL requested unsupported feature: Call Deflection");
+		return ICALL_IGNORE;
+	default:
+		err("LL error %d on ICALL", retval);
+		return ICALL_IGNORE;
+	}
+}
+
+/* Set Callback function pointer */
+int gigaset_register_to_LL(struct cardstate *cs, const char *isdnid)
+{
+	isdn_if *iif = &cs->iif;
+
+	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 = cs->driver->owner;
+	iif->channels = cs->channels;                        /* I am supporting just one channel *//* I was supporting...*/
+	iif->maxbufsize = MAX_BUF_SIZE;
+	iif->features = ISDN_FEATURE_L2_TRANS |   /* Our device is very advanced, therefore */
+		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;
+}
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