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 44 #include <net/bluetooth/bluetooth.h> 45 #include <net/bluetooth/hci_core.h> 46 47 #include "hci_uart.h" 48 49 #define VERSION "1.2" 50 51 struct h4_struct { 52 unsigned long rx_state; 53 unsigned long rx_count; 54 struct sk_buff *rx_skb; 55 struct sk_buff_head txq; 56 }; 57 58 /* H4 receiver States */ 59 #define H4_W4_PACKET_TYPE 0 60 #define H4_W4_EVENT_HDR 1 61 #define H4_W4_ACL_HDR 2 62 #define H4_W4_SCO_HDR 3 63 #define H4_W4_DATA 4 64 65 /* Initialize protocol */ 66 static int h4_open(struct hci_uart *hu) 67 { 68 struct h4_struct *h4; 69 70 BT_DBG("hu %p", hu); 71 72 h4 = kzalloc(sizeof(*h4), GFP_ATOMIC); 73 if (!h4) 74 return -ENOMEM; 75 76 skb_queue_head_init(&h4->txq); 77 78 hu->priv = h4; 79 return 0; 80 } 81 82 /* Flush protocol data */ 83 static int h4_flush(struct hci_uart *hu) 84 { 85 struct h4_struct *h4 = hu->priv; 86 87 BT_DBG("hu %p", hu); 88 89 skb_queue_purge(&h4->txq); 90 91 return 0; 92 } 93 94 /* Close protocol */ 95 static int h4_close(struct hci_uart *hu) 96 { 97 struct h4_struct *h4 = hu->priv; 98 99 hu->priv = NULL; 100 101 BT_DBG("hu %p", hu); 102 103 skb_queue_purge(&h4->txq); 104 105 if (h4->rx_skb) 106 kfree_skb(h4->rx_skb); 107 108 hu->priv = NULL; 109 kfree(h4); 110 111 return 0; 112 } 113 114 /* Enqueue frame for transmittion (padding, crc, etc) */ 115 static int h4_enqueue(struct hci_uart *hu, struct sk_buff *skb) 116 { 117 struct h4_struct *h4 = hu->priv; 118 119 BT_DBG("hu %p skb %p", hu, skb); 120 121 /* Prepend skb with frame type */ 122 memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1); 123 skb_queue_tail(&h4->txq, skb); 124 125 return 0; 126 } 127 128 static inline int h4_check_data_len(struct h4_struct *h4, int len) 129 { 130 register int room = skb_tailroom(h4->rx_skb); 131 132 BT_DBG("len %d room %d", len, room); 133 134 if (!len) { 135 hci_recv_frame(h4->rx_skb); 136 } else if (len > room) { 137 BT_ERR("Data length is too large"); 138 kfree_skb(h4->rx_skb); 139 } else { 140 h4->rx_state = H4_W4_DATA; 141 h4->rx_count = len; 142 return len; 143 } 144 145 h4->rx_state = H4_W4_PACKET_TYPE; 146 h4->rx_skb = NULL; 147 h4->rx_count = 0; 148 149 return 0; 150 } 151 152 /* Recv data */ 153 static int h4_recv(struct hci_uart *hu, void *data, int count) 154 { 155 struct h4_struct *h4 = hu->priv; 156 register char *ptr; 157 struct hci_event_hdr *eh; 158 struct hci_acl_hdr *ah; 159 struct hci_sco_hdr *sh; 160 register int len, type, dlen; 161 162 BT_DBG("hu %p count %d rx_state %ld rx_count %ld", 163 hu, count, h4->rx_state, h4->rx_count); 164 165 ptr = data; 166 while (count) { 167 if (h4->rx_count) { 168 len = min_t(unsigned int, h4->rx_count, count); 169 memcpy(skb_put(h4->rx_skb, len), ptr, len); 170 h4->rx_count -= len; count -= len; ptr += len; 171 172 if (h4->rx_count) 173 continue; 174 175 switch (h4->rx_state) { 176 case H4_W4_DATA: 177 BT_DBG("Complete data"); 178 179 hci_recv_frame(h4->rx_skb); 180 181 h4->rx_state = H4_W4_PACKET_TYPE; 182 h4->rx_skb = NULL; 183 continue; 184 185 case H4_W4_EVENT_HDR: 186 eh = hci_event_hdr(h4->rx_skb); 187 188 BT_DBG("Event header: evt 0x%2.2x plen %d", eh->evt, eh->plen); 189 190 h4_check_data_len(h4, eh->plen); 191 continue; 192 193 case H4_W4_ACL_HDR: 194 ah = hci_acl_hdr(h4->rx_skb); 195 dlen = __le16_to_cpu(ah->dlen); 196 197 BT_DBG("ACL header: dlen %d", dlen); 198 199 h4_check_data_len(h4, dlen); 200 continue; 201 202 case H4_W4_SCO_HDR: 203 sh = hci_sco_hdr(h4->rx_skb); 204 205 BT_DBG("SCO header: dlen %d", sh->dlen); 206 207 h4_check_data_len(h4, sh->dlen); 208 continue; 209 } 210 } 211 212 /* H4_W4_PACKET_TYPE */ 213 switch (*ptr) { 214 case HCI_EVENT_PKT: 215 BT_DBG("Event packet"); 216 h4->rx_state = H4_W4_EVENT_HDR; 217 h4->rx_count = HCI_EVENT_HDR_SIZE; 218 type = HCI_EVENT_PKT; 219 break; 220 221 case HCI_ACLDATA_PKT: 222 BT_DBG("ACL packet"); 223 h4->rx_state = H4_W4_ACL_HDR; 224 h4->rx_count = HCI_ACL_HDR_SIZE; 225 type = HCI_ACLDATA_PKT; 226 break; 227 228 case HCI_SCODATA_PKT: 229 BT_DBG("SCO packet"); 230 h4->rx_state = H4_W4_SCO_HDR; 231 h4->rx_count = HCI_SCO_HDR_SIZE; 232 type = HCI_SCODATA_PKT; 233 break; 234 235 default: 236 BT_ERR("Unknown HCI packet type %2.2x", (__u8)*ptr); 237 hu->hdev->stat.err_rx++; 238 ptr++; count--; 239 continue; 240 }; 241 242 ptr++; count--; 243 244 /* Allocate packet */ 245 h4->rx_skb = bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC); 246 if (!h4->rx_skb) { 247 BT_ERR("Can't allocate mem for new packet"); 248 h4->rx_state = H4_W4_PACKET_TYPE; 249 h4->rx_count = 0; 250 return 0; 251 } 252 253 h4->rx_skb->dev = (void *) hu->hdev; 254 bt_cb(h4->rx_skb)->pkt_type = type; 255 } 256 257 return count; 258 } 259 260 static struct sk_buff *h4_dequeue(struct hci_uart *hu) 261 { 262 struct h4_struct *h4 = hu->priv; 263 return skb_dequeue(&h4->txq); 264 } 265 266 static struct hci_uart_proto h4p = { 267 .id = HCI_UART_H4, 268 .open = h4_open, 269 .close = h4_close, 270 .recv = h4_recv, 271 .enqueue = h4_enqueue, 272 .dequeue = h4_dequeue, 273 .flush = h4_flush, 274 }; 275 276 int h4_init(void) 277 { 278 int err = hci_uart_register_proto(&h4p); 279 280 if (!err) 281 BT_INFO("HCI H4 protocol initialized"); 282 else 283 BT_ERR("HCI H4 protocol registration failed"); 284 285 return err; 286 } 287 288 int h4_deinit(void) 289 { 290 return hci_uart_unregister_proto(&h4p); 291 } 292