/* * bcsp_slip -- Implementation of the SLIP layer in the BCSP protocol stack * * Copyright (C) 2001  Axis Communications AB * * Author: Peter Kjellerstedt <peter.kjellerstedt@axis.com> * * 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. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA. * * Exceptionally, Axis Communications AB grants discretionary and * conditional permissions for additional use of the text contained * in the company's release of the AXIS OpenBT Stack under the * provisions set forth hereunder. * * Provided that, if you use the AXIS OpenBT Stack with other files, * that do not implement functionality as specified in the Bluetooth * System specification, to produce an executable, this does not by * itself cause the resulting executable to be covered by the GNU * General Public License. Your use of that executable is in no way * restricted on account of using the AXIS OpenBT Stack code with it. * * This exception does not however invalidate any other reasons why * the executable file might be covered by the provisions of the GNU * General Public License. * * $Id: bcsp_slip.c,v 1.8 2001/09/18 13:04:27 pkj Exp $ * *//****************** INCLUDE FILES SECTION ***********************************/#define __NO_VERSION__ /* don't define kernel_version in module.h */#ifdef __KERNEL__#include <linux/malloc.h>#include <linux/bluetooth/btcommon.h>#include <linux/bluetooth/btmem.h>#include <linux/bluetooth/bcsp.h>#include <linux/bluetooth/bcsp_debug.h>#else#include <stdlib.h>#include <errno.h>#include "include/btcommon.h"#include "include/btmem.h"#include "include/bcsp.h"#include "include/bcsp_debug.h"#endif/****************** CONSTANT AND MACRO SECTION ******************************/#if SLIP_DEBUG#define D(fmt...) printk("SLIP:      " fmt)#define PRINTPKT(data, len) print_data(NULL, data, len)#else#define D(fmt...)#define PRINTPKT(data, len)#endif/****************** TYPE DEFINITION SECTION *********************************//****************** LOCAL FUNCTION DECLARATION SECTION **********************/static void slip_send_add_byte(struct bcsp* bcsp, u8 data);#if BCSP_PARSELOWERstatic void slip_debug(const u8 *str, const struct bcsp *bcsp);#endif/****************** GLOBAL VARIABLE DECLARATION SECTION *********************//****************** LOCAL VARIABLE DECLARATION SECTION **********************//****************** FUNCTION DEFINITION SECTION *****************************/s32bcsp_slip_send(struct bcsp* bcsp){	s32 i;	D(__FUNCTION__ ":\n");	PRINTPKT(bcsp->payload, bcsp->payload_length);	if (!(bcsp->packet = kmalloc(2 * (4 + bcsp->payload_length) + 2, GFP_ATOMIC))) {		return -ENOMEM;	}	bcsp->packet_length = 0;	bcsp->packet[bcsp->packet_length++] = 0xC0;		/* Send the BCSP header */	slip_send_add_byte(bcsp, bcsp->flags);	slip_send_add_byte(bcsp, bcsp->identifier | ((bcsp->payload_length & 0x0F) << 4));	slip_send_add_byte(bcsp, bcsp->payload_length >> 4);	slip_send_add_byte(bcsp, bcsp->checksum);	/* Send the payload */	for (i = 0; i < bcsp->payload_length; i++) {		slip_send_add_byte(bcsp, bcsp->payload[i]);	}	/* Send CRC if wanted */	if (BCSP_GET_CRC_PRESENT(bcsp)) {		slip_send_add_byte(bcsp, bcsp->crc >> 8);		slip_send_add_byte(bcsp, bcsp->crc & 0xFF);	}	bcsp->packet[bcsp->packet_length++] = 0xC0;#if BCSP_PARSELOWER	slip_debug("<== ", bcsp);#endif 	bcsp_write_lower(bcsp->packet, bcsp->packet_length);	kfree(bcsp->packet);	return bcsp->packet_length;}s32bcsp_slip_receive(const u8* packet, u32 len){	static u8 buffer[4 + 4096 + 2 + 1];	static s32 length = 0;	static s32 skipping = TRUE;	struct bcsp bcsp;	s32 i = 0;	D(__FUNCTION__ "\n");	bcsp_init_packet(&bcsp);		if (skipping) {		while (i < len) {			if (packet[i++] == 0xC0) {				length = 0;				skipping = FALSE;				break;			}		}		bcsp.packet = NULL;	}	for (; i < len && !skipping; i++) {		switch (packet[i]) {		case 0xC0:			skipping = TRUE;			if (!length) {				i--;			}			else if ((bcsp.packet = kmalloc(length, GFP_ATOMIC))) {				memcpy(bcsp.packet, buffer, length);				bcsp.packet_length = length;			}			break;		case 0xDB:			switch (packet[++i]) {			case 0xDC:				buffer[length++] = 0xC0;				break;			case 0xDD:				buffer[length++] = 0xDB;				break;			default:				skipping = TRUE;				break;			}			break;		default:			buffer[length++] = packet[i];			break;		}		if (length == sizeof(buffer)) {			skipping = TRUE;		}	}	if (bcsp.packet) {#if BCSP_PARSELOWER		slip_debug("==> ", &bcsp);#endif		bcsp_integrity_receive(&bcsp);		kfree(bcsp.packet);	}        return i;}voidslip_send_add_byte(struct bcsp* bcsp, u8 data){	switch (data) {	case 0xC0:		bcsp->packet[bcsp->packet_length++] = 0xDB;		bcsp->packet[bcsp->packet_length++] = 0xDC;		break;	case 0xDB:		bcsp->packet[bcsp->packet_length++] = 0xDB;		bcsp->packet[bcsp->packet_length++] = 0xDD;		break;	default:		bcsp->packet[bcsp->packet_length++] = data;		break;	}}#if BCSP_PARSELOWER/* * Used to parse headers of sent/incoming BCSP packets * Also prints other potentially interesting stats  */#include <linux/bluetooth/hci_internal.h>voidslip_debug(const u8 *str, const struct bcsp *bcsp){	extern hci_controller hci_ctrl;	extern u8 winspace;	extern u8 txseq;	extern u8 txack;	extern u8 rxack;	extern u8 expected_rxseq;	printk("%sseq: %ld, ack: %ld, winsize: %d, acl: %d, bufc: %d, length: %d\n",	       str, BCSP_GET_SEQ(bcsp), BCSP_GET_ACK(bcsp), winspace,	       hci_ctrl.hc_buf.acl_num, buf_byte_count(-1),	       bcsp->packet_length);	printk("Status: txseq: %d, txack: %d, cur_rxack: %d, exp_rxseq: %d\n",	       txseq, txack, rxack, expected_rxseq);}#endif/****************** END OF FILE slip.c **************************************/