1 /* 2 * 3 * Bluetooth HCI UART driver 4 * 5 * Copyright (C) 2000-2001 Qualcomm Incorporated 6 * Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com> 7 * Copyright (C) 2004-2005 Marcel Holtmann <marcel@holtmann.org> 8 * 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; either version 2 of the License, or 13 * (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software 22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 23 * 24 */ 25 26 #include <linux/module.h> 27 28 #include <linux/kernel.h> 29 #include <linux/init.h> 30 #include <linux/types.h> 31 #include <linux/fcntl.h> 32 #include <linux/interrupt.h> 33 #include <linux/ptrace.h> 34 #include <linux/poll.h> 35 36 #include <linux/slab.h> 37 #include <linux/tty.h> 38 #include <linux/errno.h> 39 #include <linux/string.h> 40 #include <linux/signal.h> 41 #include <linux/ioctl.h> 42 #include <linux/skbuff.h> 43 #include <asm/unaligned.h> 44 45 #include <net/bluetooth/bluetooth.h> 46 #include <net/bluetooth/hci_core.h> 47 48 #include "hci_uart.h" 49 50 struct h4_struct { 51 struct sk_buff *rx_skb; 52 struct sk_buff_head txq; 53 }; 54 55 /* Initialize protocol */ 56 static int h4_open(struct hci_uart *hu) 57 { 58 struct h4_struct *h4; 59 60 BT_DBG("hu %p", hu); 61 62 h4 = kzalloc(sizeof(*h4), GFP_KERNEL); 63 if (!h4) 64 return -ENOMEM; 65 66 skb_queue_head_init(&h4->txq); 67 68 hu->priv = h4; 69 return 0; 70 } 71 72 /* Flush protocol data */ 73 static int h4_flush(struct hci_uart *hu) 74 { 75 struct h4_struct *h4 = hu->priv; 76 77 BT_DBG("hu %p", hu); 78 79 skb_queue_purge(&h4->txq); 80 81 return 0; 82 } 83 84 /* Close protocol */ 85 static int h4_close(struct hci_uart *hu) 86 { 87 struct h4_struct *h4 = hu->priv; 88 89 hu->priv = NULL; 90 91 BT_DBG("hu %p", hu); 92 93 skb_queue_purge(&h4->txq); 94 95 kfree_skb(h4->rx_skb); 96 97 hu->priv = NULL; 98 kfree(h4); 99 100 return 0; 101 } 102 103 /* Enqueue frame for transmittion (padding, crc, etc) */ 104 static int h4_enqueue(struct hci_uart *hu, struct sk_buff *skb) 105 { 106 struct h4_struct *h4 = hu->priv; 107 108 BT_DBG("hu %p skb %p", hu, skb); 109 110 /* Prepend skb with frame type */ 111 memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1); 112 skb_queue_tail(&h4->txq, skb); 113 114 return 0; 115 } 116 117 static const struct h4_recv_pkt h4_recv_pkts[] = { 118 { H4_RECV_ACL, .recv = hci_recv_frame }, 119 { H4_RECV_SCO, .recv = hci_recv_frame }, 120 { H4_RECV_EVENT, .recv = hci_recv_frame }, 121 }; 122 123 /* Recv data */ 124 static int h4_recv(struct hci_uart *hu, const void *data, int count) 125 { 126 struct h4_struct *h4 = hu->priv; 127 128 if (!test_bit(HCI_UART_REGISTERED, &hu->flags)) 129 return -EUNATCH; 130 131 h4->rx_skb = h4_recv_buf(hu->hdev, h4->rx_skb, data, count, 132 h4_recv_pkts, ARRAY_SIZE(h4_recv_pkts)); 133 if (IS_ERR(h4->rx_skb)) { 134 int err = PTR_ERR(h4->rx_skb); 135 BT_ERR("%s: Frame reassembly failed (%d)", hu->hdev->name, err); 136 return err; 137 } 138 139 return count; 140 } 141 142 static struct sk_buff *h4_dequeue(struct hci_uart *hu) 143 { 144 struct h4_struct *h4 = hu->priv; 145 return skb_dequeue(&h4->txq); 146 } 147 148 static const struct hci_uart_proto h4p = { 149 .id = HCI_UART_H4, 150 .name = "H4", 151 .open = h4_open, 152 .close = h4_close, 153 .recv = h4_recv, 154 .enqueue = h4_enqueue, 155 .dequeue = h4_dequeue, 156 .flush = h4_flush, 157 }; 158 159 int __init h4_init(void) 160 { 161 return hci_uart_register_proto(&h4p); 162 } 163 164 int __exit h4_deinit(void) 165 { 166 return hci_uart_unregister_proto(&h4p); 167 } 168 169 struct sk_buff *h4_recv_buf(struct hci_dev *hdev, struct sk_buff *skb, 170 const unsigned char *buffer, int count, 171 const struct h4_recv_pkt *pkts, int pkts_count) 172 { 173 while (count) { 174 int i, len; 175 176 if (!skb) { 177 for (i = 0; i < pkts_count; i++) { 178 if (buffer[0] != (&pkts[i])->type) 179 continue; 180 181 skb = bt_skb_alloc((&pkts[i])->maxlen, 182 GFP_ATOMIC); 183 if (!skb) 184 return ERR_PTR(-ENOMEM); 185 186 bt_cb(skb)->pkt_type = (&pkts[i])->type; 187 bt_cb(skb)->expect = (&pkts[i])->hlen; 188 break; 189 } 190 191 /* Check for invalid packet type */ 192 if (!skb) 193 return ERR_PTR(-EILSEQ); 194 195 count -= 1; 196 buffer += 1; 197 } 198 199 len = min_t(uint, bt_cb(skb)->expect - skb->len, count); 200 memcpy(skb_put(skb, len), buffer, len); 201 202 count -= len; 203 buffer += len; 204 205 /* Check for partial packet */ 206 if (skb->len < bt_cb(skb)->expect) 207 continue; 208 209 for (i = 0; i < pkts_count; i++) { 210 if (bt_cb(skb)->pkt_type == (&pkts[i])->type) 211 break; 212 } 213 214 if (i >= pkts_count) { 215 kfree_skb(skb); 216 return ERR_PTR(-EILSEQ); 217 } 218 219 if (skb->len == (&pkts[i])->hlen) { 220 u16 dlen; 221 222 switch ((&pkts[i])->lsize) { 223 case 0: 224 /* No variable data length */ 225 (&pkts[i])->recv(hdev, skb); 226 skb = NULL; 227 break; 228 case 1: 229 /* Single octet variable length */ 230 dlen = skb->data[(&pkts[i])->loff]; 231 bt_cb(skb)->expect += dlen; 232 233 if (skb_tailroom(skb) < dlen) { 234 kfree_skb(skb); 235 return ERR_PTR(-EMSGSIZE); 236 } 237 break; 238 case 2: 239 /* Double octet variable length */ 240 dlen = get_unaligned_le16(skb->data + 241 (&pkts[i])->loff); 242 bt_cb(skb)->expect += dlen; 243 244 if (skb_tailroom(skb) < dlen) { 245 kfree_skb(skb); 246 return ERR_PTR(-EMSGSIZE); 247 } 248 break; 249 default: 250 /* Unsupported variable length */ 251 kfree_skb(skb); 252 return ERR_PTR(-EILSEQ); 253 } 254 } else { 255 /* Complete frame */ 256 (&pkts[i])->recv(hdev, skb); 257 skb = NULL; 258 } 259 } 260 261 return skb; 262 } 263