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path: root/drivers/bluetooth/hci_bcsp.c
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-rw-r--r--drivers/bluetooth/hci_bcsp.c784
1 files changed, 784 insertions, 0 deletions
diff --git a/drivers/bluetooth/hci_bcsp.c b/drivers/bluetooth/hci_bcsp.c
new file mode 100644
index 0000000000..2a5a27d713
--- /dev/null
+++ b/drivers/bluetooth/hci_bcsp.c
@@ -0,0 +1,784 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *
+ * Bluetooth HCI UART driver
+ *
+ * Copyright (C) 2002-2003 Fabrizio Gennari <fabrizio.gennari@philips.com>
+ * Copyright (C) 2004-2005 Marcel Holtmann <marcel@holtmann.org>
+ */
+
+#include <linux/module.h>
+
+#include <linux/kernel.h>
+#include <linux/init.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 <linux/bitrev.h>
+#include <asm/unaligned.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+
+#include "hci_uart.h"
+
+static bool txcrc = true;
+static bool hciextn = true;
+
+#define BCSP_TXWINSIZE 4
+
+#define BCSP_ACK_PKT 0x05
+#define BCSP_LE_PKT 0x06
+
+struct bcsp_struct {
+ struct sk_buff_head unack; /* Unack'ed packets queue */
+ struct sk_buff_head rel; /* Reliable packets queue */
+ struct sk_buff_head unrel; /* Unreliable packets queue */
+
+ unsigned long rx_count;
+ struct sk_buff *rx_skb;
+ u8 rxseq_txack; /* rxseq == txack. */
+ u8 rxack; /* Last packet sent by us that the peer ack'ed */
+ struct timer_list tbcsp;
+ struct hci_uart *hu;
+
+ enum {
+ BCSP_W4_PKT_DELIMITER,
+ BCSP_W4_PKT_START,
+ BCSP_W4_BCSP_HDR,
+ BCSP_W4_DATA,
+ BCSP_W4_CRC
+ } rx_state;
+
+ enum {
+ BCSP_ESCSTATE_NOESC,
+ BCSP_ESCSTATE_ESC
+ } rx_esc_state;
+
+ u8 use_crc;
+ u16 message_crc;
+ u8 txack_req; /* Do we need to send ack's to the peer? */
+
+ /* Reliable packet sequence number - used to assign seq to each rel pkt. */
+ u8 msgq_txseq;
+};
+
+/* ---- 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;
+}
+
+/* ---- BCSP core ---- */
+
+static void bcsp_slip_msgdelim(struct sk_buff *skb)
+{
+ const char pkt_delim = 0xc0;
+
+ skb_put_data(skb, &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:
+ skb_put_data(skb, &esc_c0, 2);
+ break;
+ case 0xdb:
+ skb_put_data(skb, &esc_db, 2);
+ break;
+ default:
+ skb_put_data(skb, &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 (hci_skb_pkt_type(skb)) {
+ 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;
+ u16 BCSP_CRC_INIT(bcsp_txmsg_crc);
+ int rel, i;
+
+ 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;
+ }
+
+ if (hciextn && chan == 5) {
+ __le16 opcode = ((struct hci_command_hdr *)data)->opcode;
+
+ /* Vendor specific commands */
+ if (hci_opcode_ogf(__le16_to_cpu(opcode)) == 0x3f) {
+ u8 desc = *(data + HCI_COMMAND_HDR_SIZE);
+
+ if ((desc & 0xf0) == 0xc0) {
+ data += HCI_COMMAND_HDR_SIZE + 1;
+ len -= HCI_COMMAND_HDR_SIZE + 1;
+ chan = desc & 0x0f;
+ }
+ }
+ }
+
+ /* 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;
+
+ hci_skb_pkt_type(nskb) = 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 + 1) & 0x07;
+ }
+
+ if (bcsp->use_crc)
+ hdr[0] |= 0x40;
+
+ hdr[1] = ((len << 4) & 0xff) | 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]);
+
+ if (bcsp->use_crc)
+ bcsp_crc_update(&bcsp_txmsg_crc, hdr[i]);
+ }
+
+ /* Put payload */
+ for (i = 0; i < len; i++) {
+ bcsp_slip_one_byte(nskb, data[i]);
+
+ if (bcsp->use_crc)
+ bcsp_crc_update(&bcsp_txmsg_crc, data[i]);
+ }
+
+ /* Put CRC */
+ if (bcsp->use_crc) {
+ bcsp_txmsg_crc = bitrev16(bcsp_txmsg_crc);
+ bcsp_slip_one_byte(nskb, (u8)((bcsp_txmsg_crc >> 8) & 0x00ff));
+ bcsp_slip_one_byte(nskb, (u8)(bcsp_txmsg_crc & 0x00ff));
+ }
+
+ 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 = hu->priv;
+ unsigned long flags;
+ struct sk_buff *skb;
+
+ /* First of all, check for unreliable messages in the queue,
+ * since they have priority
+ */
+
+ skb = skb_dequeue(&bcsp->unrel);
+ if (skb != NULL) {
+ struct sk_buff *nskb;
+
+ nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len,
+ hci_skb_pkt_type(skb));
+ 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_nested(&bcsp->unack.lock, flags, SINGLE_DEPTH_NESTING);
+
+ if (bcsp->unack.qlen < BCSP_TXWINSIZE) {
+ skb = skb_dequeue(&bcsp->rel);
+ if (skb != NULL) {
+ struct sk_buff *nskb;
+
+ nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len,
+ hci_skb_pkt_type(skb));
+ 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)
+{
+ struct sk_buff *skb, *tmp;
+ unsigned long flags;
+ int i, pkts_to_be_removed;
+ u8 seqno;
+
+ spin_lock_irqsave(&bcsp->unack.lock, flags);
+
+ pkts_to_be_removed = skb_queue_len(&bcsp->unack);
+ 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, skb_queue_len(&bcsp->unack),
+ (seqno - 1) & 0x07);
+
+ i = 0;
+ skb_queue_walk_safe(&bcsp->unack, skb, tmp) {
+ if (i >= pkts_to_be_removed)
+ break;
+ i++;
+
+ __skb_unlink(skb, &bcsp->unack);
+ dev_kfree_skb_irq(skb);
+ }
+
+ if (skb_queue_empty(&bcsp->unack))
+ 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;
+ skb_put_data(nskb, conf_rsp_pkt, 4);
+ hci_skb_pkt_type(nskb) = 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:
+ skb_put_data(bcsp->rx_skb, &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:
+ skb_put_data(bcsp->rx_skb, &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:
+ skb_put_data(bcsp->rx_skb, &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 void bcsp_complete_rx_pkt(struct hci_uart *hu)
+{
+ struct bcsp_struct *bcsp = hu->priv;
+ int pass_up = 0;
+
+ if (bcsp->rx_skb->data[0] & 0x80) { /* reliable pkt */
+ BT_DBG("Received seqno %u from card", bcsp->rxseq_txack);
+
+ /* check the rx sequence number is as expected */
+ if ((bcsp->rx_skb->data[0] & 0x07) == bcsp->rxseq_txack) {
+ bcsp->rxseq_txack++;
+ bcsp->rxseq_txack %= 0x8;
+ } else {
+ /* handle re-transmitted packet or
+ * when packet was missed
+ */
+ BT_ERR("Out-of-order packet arrived, got %u expected %u",
+ bcsp->rx_skb->data[0] & 0x07, bcsp->rxseq_txack);
+
+ /* do not process out-of-order packet payload */
+ pass_up = 2;
+ }
+
+ /* send current txack value to all received reliable packets */
+ 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);
+
+ /* handle received ACK indications,
+ * including those from out-of-order packets
+ */
+ bcsp_pkt_cull(bcsp);
+
+ if (pass_up != 2) {
+ if ((bcsp->rx_skb->data[1] & 0x0f) == 6 &&
+ (bcsp->rx_skb->data[0] & 0x80)) {
+ hci_skb_pkt_type(bcsp->rx_skb) = HCI_ACLDATA_PKT;
+ pass_up = 1;
+ } else if ((bcsp->rx_skb->data[1] & 0x0f) == 5 &&
+ (bcsp->rx_skb->data[0] & 0x80)) {
+ hci_skb_pkt_type(bcsp->rx_skb) = HCI_EVENT_PKT;
+ pass_up = 1;
+ } else if ((bcsp->rx_skb->data[1] & 0x0f) == 7) {
+ hci_skb_pkt_type(bcsp->rx_skb) = 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 == 0) {
+ struct hci_event_hdr hdr;
+ u8 desc = (bcsp->rx_skb->data[1] & 0x0f);
+
+ if (desc != 0 && desc != 1) {
+ if (hciextn) {
+ desc |= 0xc0;
+ skb_pull(bcsp->rx_skb, 4);
+ memcpy(skb_push(bcsp->rx_skb, 1), &desc, 1);
+
+ hdr.evt = 0xff;
+ hdr.plen = bcsp->rx_skb->len;
+ memcpy(skb_push(bcsp->rx_skb, HCI_EVENT_HDR_SIZE), &hdr, HCI_EVENT_HDR_SIZE);
+ hci_skb_pkt_type(bcsp->rx_skb) = HCI_EVENT_PKT;
+
+ hci_recv_frame(hu->hdev, bcsp->rx_skb);
+ } else {
+ 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
+ kfree_skb(bcsp->rx_skb);
+ } else if (pass_up == 1) {
+ /* Pull out BCSP hdr */
+ skb_pull(bcsp->rx_skb, 4);
+
+ hci_recv_frame(hu->hdev, bcsp->rx_skb);
+ } else {
+ /* ignore packet payload of already ACKed re-transmitted
+ * packets or when a packet was missed in the BCSP window
+ */
+ kfree_skb(bcsp->rx_skb);
+ }
+
+ bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
+ bcsp->rx_skb = NULL;
+}
+
+static u16 bscp_get_crc(struct bcsp_struct *bcsp)
+{
+ return get_unaligned_be16(&bcsp->rx_skb->data[bcsp->rx_skb->len - 2]);
+}
+
+/* Recv data */
+static int bcsp_recv(struct hci_uart *hu, const void *data, int count)
+{
+ struct bcsp_struct *bcsp = hu->priv;
+ const unsigned char *ptr;
+
+ BT_DBG("hu %p count %d rx_state %d 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_skb = NULL;
+ 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_skb = NULL;
+ 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 (bitrev16(bcsp->message_crc) != bscp_get_crc(bcsp)) {
+ BT_ERR("Checksum failed: computed %04x received %04x",
+ bitrev16(bcsp->message_crc),
+ bscp_get_crc(bcsp));
+
+ kfree_skb(bcsp->rx_skb);
+ bcsp->rx_skb = NULL;
+ 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 = bt_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;
+ }
+ break;
+ }
+ break;
+ }
+ }
+ return count;
+}
+
+ /* Arrange to retransmit all messages in the relq. */
+static void bcsp_timed_event(struct timer_list *t)
+{
+ struct bcsp_struct *bcsp = from_timer(bcsp, t, tbcsp);
+ struct hci_uart *hu = bcsp->hu;
+ struct sk_buff *skb;
+ unsigned long flags;
+
+ BT_DBG("hu %p retransmitting %u pkts", hu, bcsp->unack.qlen);
+
+ spin_lock_irqsave_nested(&bcsp->unack.lock, flags, SINGLE_DEPTH_NESTING);
+
+ 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 = kzalloc(sizeof(*bcsp), GFP_KERNEL);
+ if (!bcsp)
+ return -ENOMEM;
+
+ hu->priv = bcsp;
+ bcsp->hu = hu;
+ skb_queue_head_init(&bcsp->unack);
+ skb_queue_head_init(&bcsp->rel);
+ skb_queue_head_init(&bcsp->unrel);
+
+ timer_setup(&bcsp->tbcsp, bcsp_timed_event, 0);
+
+ bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
+
+ if (txcrc)
+ bcsp->use_crc = 1;
+
+ return 0;
+}
+
+static int bcsp_close(struct hci_uart *hu)
+{
+ struct bcsp_struct *bcsp = hu->priv;
+
+ timer_shutdown_sync(&bcsp->tbcsp);
+
+ hu->priv = NULL;
+
+ BT_DBG("hu %p", hu);
+
+ skb_queue_purge(&bcsp->unack);
+ skb_queue_purge(&bcsp->rel);
+ skb_queue_purge(&bcsp->unrel);
+
+ if (bcsp->rx_skb) {
+ kfree_skb(bcsp->rx_skb);
+ bcsp->rx_skb = NULL;
+ }
+
+ kfree(bcsp);
+ return 0;
+}
+
+static const struct hci_uart_proto bcsp = {
+ .id = HCI_UART_BCSP,
+ .name = "BCSP",
+ .open = bcsp_open,
+ .close = bcsp_close,
+ .enqueue = bcsp_enqueue,
+ .dequeue = bcsp_dequeue,
+ .recv = bcsp_recv,
+ .flush = bcsp_flush
+};
+
+int __init bcsp_init(void)
+{
+ return hci_uart_register_proto(&bcsp);
+}
+
+int __exit bcsp_deinit(void)
+{
+ return hci_uart_unregister_proto(&bcsp);
+}
+
+module_param(txcrc, bool, 0644);
+MODULE_PARM_DESC(txcrc, "Transmit CRC with every BCSP packet");
+
+module_param(hciextn, bool, 0644);
+MODULE_PARM_DESC(hciextn, "Convert HCI Extensions into BCSP packets");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-28 13:30:51 +0000