i4l.c

来自「LINUX 2.6.17.4的源码」· C语言 代码 · 共 575 行 · 第 1/2 页

/*
 * Stuff used by all variants of the driver
 *
 * Copyright (c) 2001 by Stefan Eilers,
 *                       Hansjoerg Lipp <[e-mail]>,
 *                       Tilman Schmidt <[e-mail]>.
 *
 * =====================================================================
 *	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))) {
		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;

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

	if (!len) {
		if (ack)
			notice("%s: not ACKing empty packet", __func__);
		return 0;
	}
	if (len > MAX_BUF_SIZE) {
		err("%s: packet too large (%d bytes)", __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);
	//isdn_ctrl response;
	//unsigned long flags;
	struct bc_state *bcs;
	int retval = 0;
	struct setup_parm *sp;
	unsigned param;
	unsigned long flags;

	gigaset_debugdrivers();

	if (!cs) {
		warn("LL tried to access unknown device with nr. %d",
		     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);

		warn("ISDN_CMD_IOCTL is not supported.");
		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) {
			err("ISDN_CMD_DIAL: invalid channel (%d)",
			    (int) cntrl->arg);
			return -EINVAL;
		}

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

		if (!gigaset_get_channel(bcs)) {
			err("ISDN_CMD_DIAL: 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;

		spin_lock_irqsave(&cs->lock, flags);
		param = bcs->at_state.seq_index;
		spin_unlock_irqrestore(&cs->lock, flags);

		if (!gigaset_add_event(cs, &bcs->at_state, EV_DIAL, sp, param,
				       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) {
			err("ISDN_CMD_ACCEPTD: 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;
		}

		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) {
			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;
		}

		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) {
			err("ISDN_CMD_SETL2: 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;
		}

		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) {
			err("ISDN_CMD_SETL3: invalid channel (%u)",
			    (unsigned) cntrl->arg & 0xff);
			return -EINVAL;
		}

		if (cntrl->arg >> 8 != ISDN_PROTO_L3_TRANS) {
			err("ISDN_CMD_SETL3: invalid protocol %lu",
			    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) {
			err("ISDN_CMD_ALERT: invalid channel (%d)",
			    (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");