patch-2.4.21 linux-2.4.21/drivers/bluetooth/hci_bcsp.c

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diff -urN linux-2.4.20/drivers/bluetooth/hci_bcsp.c linux-2.4.21/drivers/bluetooth/hci_bcsp.c
@@ -0,0 +1,710 @@
+/* 
+   BlueCore Serial Protocol (BCSP) for Linux Bluetooth stack (BlueZ).
+   Copyright 2002 by Fabrizio Gennari <fabrizio.gennari@philips.com>
+
+   Based on
+       hci_h4.c  by Maxim Krasnyansky <maxk@qualcomm.com>
+       ABCSP     by Carl Orsborn <cjo@csr.com>
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License version 2 as
+   published by the Free Software Foundation;
+
+   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
+   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
+   CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES 
+   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 
+   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 
+   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS, 
+   COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS 
+   SOFTWARE IS DISCLAIMED.
+*/
+
+/*
+ * $Id: hci_bcsp.c,v 1.2 2002/09/26 05:05:14 maxk Exp $
+ */
+
+#define VERSION "0.1"
+
+#include <linux/config.h>
+#include <linux/module.h>
+
+#include <linux/version.h>
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/interrupt.h>
+#include <linux/ptrace.h>
+#include <linux/poll.h>
+
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/signal.h>
+#include <linux/ioctl.h>
+#include <linux/skbuff.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+#include "hci_uart.h"
+#include "hci_bcsp.h"
+
+#ifndef HCI_UART_DEBUG
+#undef  BT_DBG
+#define BT_DBG( A... )
+#undef  BT_DMP
+#define BT_DMP( A... )
+#endif
+
+/* ---- BCSP CRC calculation ---- */
+
+/* Table for calculating CRC for polynomial 0x1021, LSB processed first,
+initial value 0xffff, bits shifted in reverse order. */
+
+static const u16 crc_table[] = {
+	0x0000, 0x1081, 0x2102, 0x3183,
+	0x4204, 0x5285, 0x6306, 0x7387,
+	0x8408, 0x9489, 0xa50a, 0xb58b,
+	0xc60c, 0xd68d, 0xe70e, 0xf78f
+};
+
+/* Initialise the crc calculator */
+#define BCSP_CRC_INIT(x) x = 0xffff
+
+/*
+   Update crc with next data byte
+
+   Implementation note
+        The data byte is treated as two nibbles.  The crc is generated
+        in reverse, i.e., bits are fed into the register from the top.
+*/
+static void bcsp_crc_update(u16 *crc, u8 d)
+{
+	u16 reg = *crc;
+
+	reg = (reg >> 4) ^ crc_table[(reg ^ d) & 0x000f];
+	reg = (reg >> 4) ^ crc_table[(reg ^ (d >> 4)) & 0x000f];
+
+	*crc = reg;
+}
+
+/*
+   Get reverse of generated crc
+
+   Implementation note
+        The crc generator (bcsp_crc_init() and bcsp_crc_update())
+        creates a reversed crc, so it needs to be swapped back before
+        being passed on.
+*/
+static u16 bcsp_crc_reverse(u16 crc)
+{
+	u16 b, rev;
+
+	for (b = 0, rev = 0; b < 16; b++) {
+		rev = rev << 1;
+		rev |= (crc & 1);
+		crc = crc >> 1;
+	}
+	return (rev);
+}
+
+/* ---- BCSP core ---- */
+
+static void bcsp_slip_msgdelim(struct sk_buff *skb)
+{
+	const char pkt_delim = 0xc0;
+	memcpy(skb_put(skb, 1), &pkt_delim, 1);
+}
+
+static void bcsp_slip_one_byte(struct sk_buff *skb, u8 c)
+{
+	const char esc_c0[2] = { 0xdb, 0xdc };
+	const char esc_db[2] = { 0xdb, 0xdd };
+
+	switch (c) {
+	case 0xc0:
+		memcpy(skb_put(skb, 2), &esc_c0, 2);
+		break;
+	case 0xdb:
+		memcpy(skb_put(skb, 2), &esc_db, 2);
+		break;
+	default:
+		memcpy(skb_put(skb, 1), &c, 1);
+	}
+}
+
+static int bcsp_enqueue(struct hci_uart *hu, struct sk_buff *skb)
+{
+	struct bcsp_struct *bcsp = hu->priv;
+
+	if (skb->len > 0xFFF) {
+		BT_ERR("Packet too long");
+		kfree_skb(skb);
+		return 0;
+	}
+
+	switch (skb->pkt_type) {
+	case HCI_ACLDATA_PKT:
+	case HCI_COMMAND_PKT:
+		skb_queue_tail(&bcsp->rel, skb);
+		break;
+
+	case HCI_SCODATA_PKT:
+		skb_queue_tail(&bcsp->unrel, skb);
+		break;
+		
+	default:
+		BT_ERR("Unknown packet type");
+		kfree_skb(skb);
+		break;
+	}
+	return 0;
+}
+
+static struct sk_buff *bcsp_prepare_pkt(struct bcsp_struct *bcsp, u8 *data,
+		int len, int pkt_type)
+{
+	struct sk_buff *nskb;
+	u8  hdr[4], chan;
+	int rel, i;
+
+#ifdef CONFIG_BLUEZ_HCIUART_BCSP_TXCRC
+	u16 BCSP_CRC_INIT(bcsp_txmsg_crc);
+#endif
+
+	switch (pkt_type) {
+	case HCI_ACLDATA_PKT:
+		chan = 6;	/* BCSP ACL channel */
+		rel = 1;	/* reliable channel */
+		break;
+	case HCI_COMMAND_PKT:
+		chan = 5;	/* BCSP cmd/evt channel */
+		rel = 1;	/* reliable channel */
+		break;
+	case HCI_SCODATA_PKT:
+		chan = 7;	/* BCSP SCO channel */
+		rel = 0;	/* unreliable channel */
+		break;
+	case BCSP_LE_PKT:
+		chan = 1;	/* BCSP LE channel */
+		rel = 0;	/* unreliable channel */
+		break;
+	case BCSP_ACK_PKT:
+		chan = 0;	/* BCSP internal channel */
+		rel = 0;	/* unreliable channel */
+		break;
+	default:
+		BT_ERR("Unknown packet type");
+		return NULL;
+	}
+
+	/* Max len of packet: (original len +4(bcsp hdr) +2(crc))*2
+	   (because bytes 0xc0 and 0xdb are escaped, worst case is
+	   when the packet is all made of 0xc0 and 0xdb :) )
+	   + 2 (0xc0 delimiters at start and end). */
+
+	nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
+	if (!nskb)
+		return NULL;
+
+	nskb->pkt_type = pkt_type;
+
+	bcsp_slip_msgdelim(nskb);
+
+	hdr[0] = bcsp->rxseq_txack << 3;
+	bcsp->txack_req = 0;
+	BT_DBG("We request packet no %u to card", bcsp->rxseq_txack);
+
+	if (rel) {
+		hdr[0] |= 0x80 + bcsp->msgq_txseq;
+		BT_DBG("Sending packet with seqno %u", bcsp->msgq_txseq);
+		bcsp->msgq_txseq = ++(bcsp->msgq_txseq) & 0x07;
+	}
+#ifdef  CONFIG_BLUEZ_HCIUART_BCSP_TXCRC
+	hdr[0] |= 0x40;
+#endif
+
+	hdr[1]  = (len << 4) & 0xFF;
+	hdr[1] |= chan;
+	hdr[2]  = len >> 4;
+	hdr[3]  = ~(hdr[0] + hdr[1] + hdr[2]);
+
+	/* Put BCSP header */
+	for (i = 0; i < 4; i++) {
+		bcsp_slip_one_byte(nskb, hdr[i]);
+#ifdef  CONFIG_BLUEZ_HCIUART_BCSP_TXCRC
+		bcsp_crc_update(&bcsp_txmsg_crc, hdr[i]);
+#endif
+	}
+
+	/* Put payload */
+	for (i = 0; i < len; i++) {
+		bcsp_slip_one_byte(nskb, data[i]);
+#ifdef  CONFIG_BLUEZ_HCIUART_BCSP_TXCRC
+		bcsp_crc_update(&bcsp_txmsg_crc, data[i]);
+#endif
+	}
+
+#ifdef CONFIG_BLUEZ_HCIUART_BCSP_TXCRC
+	/* Put CRC */
+	bcsp_txmsg_crc = bcsp_crc_reverse(bcsp_txmsg_crc);
+	bcsp_slip_one_byte(nskb, (u8) ((bcsp_txmsg_crc >> 8) & 0x00ff));
+	bcsp_slip_one_byte(nskb, (u8) (bcsp_txmsg_crc & 0x00ff));
+#endif
+
+	bcsp_slip_msgdelim(nskb);
+	return nskb;
+}
+
+/* This is a rewrite of pkt_avail in ABCSP */
+static struct sk_buff *bcsp_dequeue(struct hci_uart *hu)
+{
+	struct bcsp_struct *bcsp = (struct bcsp_struct *) hu->priv;
+	unsigned long flags;
+	struct sk_buff *skb;
+	
+	/* First of all, check for unreliable messages in the queue,
+	   since they have priority */
+
+	if ((skb = skb_dequeue(&bcsp->unrel)) != NULL) {
+		struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len, skb->pkt_type);
+		if (nskb) {
+			kfree_skb(skb);
+			return nskb;
+		} else {
+			skb_queue_head(&bcsp->unrel, skb);
+			BT_ERR("Could not dequeue pkt because alloc_skb failed");
+		}
+	}
+
+	/* Now, try to send a reliable pkt. We can only send a
+	   reliable packet if the number of packets sent but not yet ack'ed
+	   is < than the winsize */
+
+	spin_lock_irqsave(&bcsp->unack.lock, flags);
+
+	if (bcsp->unack.qlen < BCSP_TXWINSIZE && (skb = skb_dequeue(&bcsp->rel)) != NULL) {
+		struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len, skb->pkt_type);
+		if (nskb) {
+			__skb_queue_tail(&bcsp->unack, skb);
+			mod_timer(&bcsp->tbcsp, jiffies + HZ / 4);
+			spin_unlock_irqrestore(&bcsp->unack.lock, flags);
+			return nskb;
+		} else {
+			skb_queue_head(&bcsp->rel, skb);
+			BT_ERR("Could not dequeue pkt because alloc_skb failed");
+		}
+	}
+
+	spin_unlock_irqrestore(&bcsp->unack.lock, flags);
+
+
+	/* We could not send a reliable packet, either because there are
+	   none or because there are too many unack'ed pkts. Did we receive
+	   any packets we have not acknowledged yet ? */
+
+	if (bcsp->txack_req) {
+		/* if so, craft an empty ACK pkt and send it on BCSP unreliable
+		   channel 0 */
+		struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, NULL, 0, BCSP_ACK_PKT);
+		return nskb;
+	}
+
+	/* We have nothing to send */
+	return NULL;
+}
+
+static int bcsp_flush(struct hci_uart *hu)
+{
+	BT_DBG("hu %p", hu);
+	return 0;
+}
+
+/* Remove ack'ed packets */
+static void bcsp_pkt_cull(struct bcsp_struct *bcsp)
+{
+	unsigned long flags;
+	struct sk_buff *skb;
+	int i, pkts_to_be_removed;
+	u8 seqno;
+
+	spin_lock_irqsave(&bcsp->unack.lock, flags);
+
+	pkts_to_be_removed = bcsp->unack.qlen;
+	seqno = bcsp->msgq_txseq;
+
+	while (pkts_to_be_removed) {
+		if (bcsp->rxack == seqno)
+			break;
+		pkts_to_be_removed--;
+		seqno = (seqno - 1) & 0x07;
+	}
+
+	if (bcsp->rxack != seqno)
+		BT_ERR("Peer acked invalid packet");
+
+	BT_DBG("Removing %u pkts out of %u, up to seqno %u",
+	       pkts_to_be_removed, bcsp->unack.qlen, (seqno - 1) & 0x07);
+
+	for (i = 0, skb = ((struct sk_buff *) &bcsp->unack)->next; i < pkts_to_be_removed
+			&& skb != (struct sk_buff *) &bcsp->unack; i++) {
+		struct sk_buff *nskb;
+
+		nskb = skb->next;
+		__skb_unlink(skb, &bcsp->unack);
+		kfree_skb(skb);
+		skb = nskb;
+	}
+	if (bcsp->unack.qlen == 0)
+		del_timer(&bcsp->tbcsp);
+	spin_unlock_irqrestore(&bcsp->unack.lock, flags);
+
+	if (i != pkts_to_be_removed)
+		BT_ERR("Removed only %u out of %u pkts", i, pkts_to_be_removed);
+}
+
+/* Handle BCSP link-establishment packets. When we
+   detect a "sync" packet, symptom that the BT module has reset,
+   we do nothing :) (yet) */
+static void bcsp_handle_le_pkt(struct hci_uart *hu)
+{
+	struct bcsp_struct *bcsp = hu->priv;
+	u8 conf_pkt[4]     = { 0xad, 0xef, 0xac, 0xed };
+	u8 conf_rsp_pkt[4] = { 0xde, 0xad, 0xd0, 0xd0 };
+	u8 sync_pkt[4]     = { 0xda, 0xdc, 0xed, 0xed };
+
+	/* spot "conf" pkts and reply with a "conf rsp" pkt */
+	if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&
+			!memcmp(&bcsp->rx_skb->data[4], conf_pkt, 4)) {
+		struct sk_buff *nskb = alloc_skb(4, GFP_ATOMIC);
+
+		BT_DBG("Found a LE conf pkt");
+		if (!nskb)
+			return;
+		memcpy(skb_put(nskb, 4), conf_rsp_pkt, 4);
+		nskb->pkt_type = BCSP_LE_PKT;
+
+		skb_queue_head(&bcsp->unrel, nskb);
+		hci_uart_tx_wakeup(hu);
+	}
+	/* Spot "sync" pkts. If we find one...disaster! */
+	else if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&
+			!memcmp(&bcsp->rx_skb->data[4], sync_pkt, 4)) {
+		BT_ERR("Found a LE sync pkt, card has reset");
+	}
+}
+
+static inline void bcsp_unslip_one_byte(struct bcsp_struct *bcsp, unsigned char byte)
+{
+	const u8 c0 = 0xc0, db = 0xdb;
+
+	switch (bcsp->rx_esc_state) {
+	case BCSP_ESCSTATE_NOESC:
+		switch (byte) {
+		case 0xdb:
+			bcsp->rx_esc_state = BCSP_ESCSTATE_ESC;
+			break;
+		default:
+			memcpy(skb_put(bcsp->rx_skb, 1), &byte, 1);
+			if ((bcsp->rx_skb-> data[0] & 0x40) != 0 && 
+					bcsp->rx_state != BCSP_W4_CRC)
+				bcsp_crc_update(&bcsp->message_crc, byte);
+			bcsp->rx_count--;
+		}
+		break;
+
+	case BCSP_ESCSTATE_ESC:
+		switch (byte) {
+		case 0xdc:
+			memcpy(skb_put(bcsp->rx_skb, 1), &c0, 1);
+			if ((bcsp->rx_skb-> data[0] & 0x40) != 0 && 
+					bcsp->rx_state != BCSP_W4_CRC)
+				bcsp_crc_update(&bcsp-> message_crc, 0xc0);
+			bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
+			bcsp->rx_count--;
+			break;
+
+		case 0xdd:
+			memcpy(skb_put(bcsp->rx_skb, 1), &db, 1);
+			if ((bcsp->rx_skb-> data[0] & 0x40) != 0 && 
+					bcsp->rx_state != BCSP_W4_CRC) 
+				bcsp_crc_update(&bcsp-> message_crc, 0xdb);
+			bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
+			bcsp->rx_count--;
+			break;
+
+		default:
+			BT_ERR ("Invalid byte %02x after esc byte", byte);
+			kfree_skb(bcsp->rx_skb);
+			bcsp->rx_skb = NULL;
+			bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
+			bcsp->rx_count = 0;
+		}
+	}
+}
+
+static inline void bcsp_complete_rx_pkt(struct hci_uart *hu)
+{
+	struct bcsp_struct *bcsp = hu->priv;
+	int pass_up;
+
+	if (bcsp->rx_skb->data[0] & 0x80) {	/* reliable pkt */
+		BT_DBG("Received seqno %u from card", bcsp->rxseq_txack);
+		bcsp->rxseq_txack++;
+		bcsp->rxseq_txack %= 0x8;
+		bcsp->txack_req    = 1;
+
+		/* If needed, transmit an ack pkt */
+		hci_uart_tx_wakeup(hu);
+	}
+
+	bcsp->rxack = (bcsp->rx_skb->data[0] >> 3) & 0x07;
+	BT_DBG("Request for pkt %u from card", bcsp->rxack);
+
+	bcsp_pkt_cull(bcsp);
+	if ((bcsp->rx_skb->data[1] & 0x0f) == 6 &&
+			bcsp->rx_skb->data[0] & 0x80) {
+		bcsp->rx_skb->pkt_type = HCI_ACLDATA_PKT;
+		pass_up = 1;
+	} else if ((bcsp->rx_skb->data[1] & 0x0f) == 5 &&
+			bcsp->rx_skb->data[0] & 0x80) {
+		bcsp->rx_skb->pkt_type = HCI_EVENT_PKT;
+		pass_up = 1;
+	} else if ((bcsp->rx_skb->data[1] & 0x0f) == 7) {
+		bcsp->rx_skb->pkt_type = HCI_SCODATA_PKT;
+		pass_up = 1;
+	} else if ((bcsp->rx_skb->data[1] & 0x0f) == 1 &&
+			!(bcsp->rx_skb->data[0] & 0x80)) {
+		bcsp_handle_le_pkt(hu);
+		pass_up = 0;
+	} else
+		pass_up = 0;
+
+	if (!pass_up) {
+		if ((bcsp->rx_skb->data[1] & 0x0f) != 0 &&
+	    		(bcsp->rx_skb->data[1] & 0x0f) != 1) {
+			BT_ERR ("Packet for unknown channel (%u %s)",
+				bcsp->rx_skb->data[1] & 0x0f,
+				bcsp->rx_skb->data[0] & 0x80 ? 
+				"reliable" : "unreliable");
+		}
+		kfree_skb(bcsp->rx_skb);
+	} else {
+		/* Pull out BCSP hdr */
+		skb_pull(bcsp->rx_skb, 4);
+
+		hci_recv_frame(bcsp->rx_skb);
+	}
+	bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
+	bcsp->rx_skb = NULL;
+}
+
+/* Recv data */
+static int bcsp_recv(struct hci_uart *hu, void *data, int count)
+{
+	struct bcsp_struct *bcsp = hu->priv;
+	register unsigned char *ptr;
+
+	BT_DBG("hu %p count %d rx_state %ld rx_count %ld", 
+		hu, count, bcsp->rx_state, bcsp->rx_count);
+
+	ptr = data;
+	while (count) {
+		if (bcsp->rx_count) {
+			if (*ptr == 0xc0) {
+				BT_ERR("Short BCSP packet");
+				kfree_skb(bcsp->rx_skb);
+				bcsp->rx_state = BCSP_W4_PKT_START;
+				bcsp->rx_count = 0;
+			} else
+				bcsp_unslip_one_byte(bcsp, *ptr);
+
+			ptr++; count--;
+			continue;
+		}
+
+		switch (bcsp->rx_state) {
+		case BCSP_W4_BCSP_HDR:
+			if ((0xff & (u8) ~ (bcsp->rx_skb->data[0] + bcsp->rx_skb->data[1] +
+					bcsp->rx_skb->data[2])) != bcsp->rx_skb->data[3]) {
+				BT_ERR("Error in BCSP hdr checksum");
+				kfree_skb(bcsp->rx_skb);
+				bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
+				bcsp->rx_count = 0;
+				continue;
+			}
+			if (bcsp->rx_skb->data[0] & 0x80	/* reliable pkt */
+			    		&& (bcsp->rx_skb->data[0] & 0x07) != bcsp->rxseq_txack) {
+				BT_ERR ("Out-of-order packet arrived, got %u expected %u",
+					bcsp->rx_skb->data[0] & 0x07, bcsp->rxseq_txack);
+
+				kfree_skb(bcsp->rx_skb);
+				bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
+				bcsp->rx_count = 0;
+				continue;
+			}
+			bcsp->rx_state = BCSP_W4_DATA;
+			bcsp->rx_count = (bcsp->rx_skb->data[1] >> 4) + 
+					(bcsp->rx_skb->data[2] << 4);	/* May be 0 */
+			continue;
+
+		case BCSP_W4_DATA:
+			if (bcsp->rx_skb->data[0] & 0x40) {	/* pkt with crc */
+				bcsp->rx_state = BCSP_W4_CRC;
+				bcsp->rx_count = 2;
+			} else
+				bcsp_complete_rx_pkt(hu);
+			continue;
+
+		case BCSP_W4_CRC:
+			if (bcsp_crc_reverse(bcsp->message_crc) !=
+					(bcsp->rx_skb->data[bcsp->rx_skb->len - 2] << 8) +
+					bcsp->rx_skb->data[bcsp->rx_skb->len - 1]) {
+
+				BT_ERR ("Checksum failed: computed %04x received %04x",
+					bcsp_crc_reverse(bcsp->message_crc),
+				     	(bcsp->rx_skb-> data[bcsp->rx_skb->len - 2] << 8) +
+				     	bcsp->rx_skb->data[bcsp->rx_skb->len - 1]);
+
+				kfree_skb(bcsp->rx_skb);
+				bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
+				bcsp->rx_count = 0;
+				continue;
+			}
+			skb_trim(bcsp->rx_skb, bcsp->rx_skb->len - 2);
+			bcsp_complete_rx_pkt(hu);
+			continue;
+
+		case BCSP_W4_PKT_DELIMITER:
+			switch (*ptr) {
+			case 0xc0:
+				bcsp->rx_state = BCSP_W4_PKT_START;
+				break;
+			default:
+				/*BT_ERR("Ignoring byte %02x", *ptr);*/
+				break;
+			}
+			ptr++; count--;
+			break;
+
+		case BCSP_W4_PKT_START:
+			switch (*ptr) {
+			case 0xc0:
+				ptr++; count--;
+				break;
+
+			default:
+				bcsp->rx_state = BCSP_W4_BCSP_HDR;
+				bcsp->rx_count = 4;
+				bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
+				BCSP_CRC_INIT(bcsp->message_crc);
+				
+				/* Do not increment ptr or decrement count
+				 * Allocate packet. Max len of a BCSP pkt= 
+				 * 0xFFF (payload) +4 (header) +2 (crc) */
+
+				bcsp->rx_skb = bluez_skb_alloc(0x1005, GFP_ATOMIC);
+				if (!bcsp->rx_skb) {
+					BT_ERR("Can't allocate mem for new packet");
+					bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
+					bcsp->rx_count = 0;
+					return 0;
+				}
+				bcsp->rx_skb->dev = (void *) &hu->hdev;
+				break;
+			}
+			break;
+		}
+	}
+	return count;
+}
+
+	/* Arrange to retransmit all messages in the relq. */
+static void bcsp_timed_event(unsigned long arg)
+{
+	struct hci_uart *hu = (struct hci_uart *) arg;
+	struct bcsp_struct *bcsp = (struct bcsp_struct *) hu->priv;
+	struct sk_buff *skb;
+	unsigned long flags;
+
+	BT_ERR("Timeout, retransmitting %u pkts", bcsp->unack.qlen);
+	spin_lock_irqsave(&bcsp->unack.lock, flags);
+
+	while ((skb = __skb_dequeue_tail(&bcsp->unack)) != NULL) {
+		bcsp->msgq_txseq = (bcsp->msgq_txseq - 1) & 0x07;
+		skb_queue_head(&bcsp->rel, skb);
+	}
+
+	spin_unlock_irqrestore(&bcsp->unack.lock, flags);
+
+	hci_uart_tx_wakeup(hu);
+}
+
+static int bcsp_open(struct hci_uart *hu)
+{
+	struct bcsp_struct *bcsp;
+
+	BT_DBG("hu %p", hu);
+
+	bcsp = kmalloc(sizeof(*bcsp), GFP_ATOMIC);
+	if (!bcsp)
+		return -ENOMEM;
+	memset(bcsp, 0, sizeof(*bcsp));
+
+	hu->priv = bcsp;
+	skb_queue_head_init(&bcsp->unack);
+	skb_queue_head_init(&bcsp->rel);
+	skb_queue_head_init(&bcsp->unrel);
+
+	init_timer(&bcsp->tbcsp);
+	bcsp->tbcsp.function = bcsp_timed_event;
+	bcsp->tbcsp.data     = (u_long) hu;
+
+	bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
+
+	return 0;
+}
+
+static int bcsp_close(struct hci_uart *hu)
+{
+	struct bcsp_struct *bcsp = hu->priv;
+	hu->priv = NULL;
+
+	BT_DBG("hu %p", hu);
+
+	skb_queue_purge(&bcsp->unack);
+	skb_queue_purge(&bcsp->rel);
+	skb_queue_purge(&bcsp->unrel);
+	del_timer(&bcsp->tbcsp);
+
+	kfree(bcsp);
+	return 0;
+}
+
+static struct hci_uart_proto bcsp = {
+	id:      HCI_UART_BCSP,
+	open:    bcsp_open,
+	close:   bcsp_close,
+	enqueue: bcsp_enqueue,
+	dequeue: bcsp_dequeue,
+	recv:    bcsp_recv,
+	flush:   bcsp_flush
+};
+
+int bcsp_init(void)
+{
+	return hci_uart_register_proto(&bcsp);
+}
+
+int bcsp_deinit(void)
+{
+	return hci_uart_unregister_proto(&bcsp);
+}
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)