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/config.h> 27 #include <linux/module.h> 28 29 #include <linux/kernel.h> 30 #include <linux/init.h> 31 #include <linux/sched.h> 32 #include <linux/types.h> 33 #include <linux/fcntl.h> 34 #include <linux/interrupt.h> 35 #include <linux/ptrace.h> 36 #include <linux/poll.h> 37 38 #include <linux/slab.h> 39 #include <linux/tty.h> 40 #include <linux/errno.h> 41 #include <linux/string.h> 42 #include <linux/signal.h> 43 #include <linux/ioctl.h> 44 #include <linux/skbuff.h> 45 46 #include <net/bluetooth/bluetooth.h> 47 #include <net/bluetooth/hci_core.h> 48 49 #include "hci_uart.h" 50 51 #ifndef CONFIG_BT_HCIUART_DEBUG 52 #undef BT_DBG 53 #define BT_DBG( A... ) 54 #endif 55 56 #define VERSION "1.2" 57 58 struct h4_struct { 59 unsigned long rx_state; 60 unsigned long rx_count; 61 struct sk_buff *rx_skb; 62 struct sk_buff_head txq; 63 }; 64 65 /* H4 receiver States */ 66 #define H4_W4_PACKET_TYPE 0 67 #define H4_W4_EVENT_HDR 1 68 #define H4_W4_ACL_HDR 2 69 #define H4_W4_SCO_HDR 3 70 #define H4_W4_DATA 4 71 72 /* Initialize protocol */ 73 static int h4_open(struct hci_uart *hu) 74 { 75 struct h4_struct *h4; 76 77 BT_DBG("hu %p", hu); 78 79 h4 = kmalloc(sizeof(*h4), GFP_ATOMIC); 80 if (!h4) 81 return -ENOMEM; 82 83 memset(h4, 0, sizeof(*h4)); 84 85 skb_queue_head_init(&h4->txq); 86 87 hu->priv = h4; 88 return 0; 89 } 90 91 /* Flush protocol data */ 92 static int h4_flush(struct hci_uart *hu) 93 { 94 struct h4_struct *h4 = hu->priv; 95 96 BT_DBG("hu %p", hu); 97 98 skb_queue_purge(&h4->txq); 99 100 return 0; 101 } 102 103 /* Close protocol */ 104 static int h4_close(struct hci_uart *hu) 105 { 106 struct h4_struct *h4 = hu->priv; 107 108 hu->priv = NULL; 109 110 BT_DBG("hu %p", hu); 111 112 skb_queue_purge(&h4->txq); 113 114 if (h4->rx_skb) 115 kfree_skb(h4->rx_skb); 116 117 hu->priv = NULL; 118 kfree(h4); 119 120 return 0; 121 } 122 123 /* Enqueue frame for transmittion (padding, crc, etc) */ 124 static int h4_enqueue(struct hci_uart *hu, struct sk_buff *skb) 125 { 126 struct h4_struct *h4 = hu->priv; 127 128 BT_DBG("hu %p skb %p", hu, skb); 129 130 /* Prepend skb with frame type */ 131 memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1); 132 skb_queue_tail(&h4->txq, skb); 133 134 return 0; 135 } 136 137 static inline int h4_check_data_len(struct h4_struct *h4, int len) 138 { 139 register int room = skb_tailroom(h4->rx_skb); 140 141 BT_DBG("len %d room %d", len, room); 142 143 if (!len) { 144 hci_recv_frame(h4->rx_skb); 145 } else if (len > room) { 146 BT_ERR("Data length is too large"); 147 kfree_skb(h4->rx_skb); 148 } else { 149 h4->rx_state = H4_W4_DATA; 150 h4->rx_count = len; 151 return len; 152 } 153 154 h4->rx_state = H4_W4_PACKET_TYPE; 155 h4->rx_skb = NULL; 156 h4->rx_count = 0; 157 158 return 0; 159 } 160 161 /* Recv data */ 162 static int h4_recv(struct hci_uart *hu, void *data, int count) 163 { 164 struct h4_struct *h4 = hu->priv; 165 register char *ptr; 166 struct hci_event_hdr *eh; 167 struct hci_acl_hdr *ah; 168 struct hci_sco_hdr *sh; 169 register int len, type, dlen; 170 171 BT_DBG("hu %p count %d rx_state %ld rx_count %ld", 172 hu, count, h4->rx_state, h4->rx_count); 173 174 ptr = data; 175 while (count) { 176 if (h4->rx_count) { 177 len = min_t(unsigned int, h4->rx_count, count); 178 memcpy(skb_put(h4->rx_skb, len), ptr, len); 179 h4->rx_count -= len; count -= len; ptr += len; 180 181 if (h4->rx_count) 182 continue; 183 184 switch (h4->rx_state) { 185 case H4_W4_DATA: 186 BT_DBG("Complete data"); 187 188 hci_recv_frame(h4->rx_skb); 189 190 h4->rx_state = H4_W4_PACKET_TYPE; 191 h4->rx_skb = NULL; 192 continue; 193 194 case H4_W4_EVENT_HDR: 195 eh = (struct hci_event_hdr *) h4->rx_skb->data; 196 197 BT_DBG("Event header: evt 0x%2.2x plen %d", eh->evt, eh->plen); 198 199 h4_check_data_len(h4, eh->plen); 200 continue; 201 202 case H4_W4_ACL_HDR: 203 ah = (struct hci_acl_hdr *) h4->rx_skb->data; 204 dlen = __le16_to_cpu(ah->dlen); 205 206 BT_DBG("ACL header: dlen %d", dlen); 207 208 h4_check_data_len(h4, dlen); 209 continue; 210 211 case H4_W4_SCO_HDR: 212 sh = (struct hci_sco_hdr *) h4->rx_skb->data; 213 214 BT_DBG("SCO header: dlen %d", sh->dlen); 215 216 h4_check_data_len(h4, sh->dlen); 217 continue; 218 } 219 } 220 221 /* H4_W4_PACKET_TYPE */ 222 switch (*ptr) { 223 case HCI_EVENT_PKT: 224 BT_DBG("Event packet"); 225 h4->rx_state = H4_W4_EVENT_HDR; 226 h4->rx_count = HCI_EVENT_HDR_SIZE; 227 type = HCI_EVENT_PKT; 228 break; 229 230 case HCI_ACLDATA_PKT: 231 BT_DBG("ACL packet"); 232 h4->rx_state = H4_W4_ACL_HDR; 233 h4->rx_count = HCI_ACL_HDR_SIZE; 234 type = HCI_ACLDATA_PKT; 235 break; 236 237 case HCI_SCODATA_PKT: 238 BT_DBG("SCO packet"); 239 h4->rx_state = H4_W4_SCO_HDR; 240 h4->rx_count = HCI_SCO_HDR_SIZE; 241 type = HCI_SCODATA_PKT; 242 break; 243 244 default: 245 BT_ERR("Unknown HCI packet type %2.2x", (__u8)*ptr); 246 hu->hdev->stat.err_rx++; 247 ptr++; count--; 248 continue; 249 }; 250 251 ptr++; count--; 252 253 /* Allocate packet */ 254 h4->rx_skb = bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC); 255 if (!h4->rx_skb) { 256 BT_ERR("Can't allocate mem for new packet"); 257 h4->rx_state = H4_W4_PACKET_TYPE; 258 h4->rx_count = 0; 259 return 0; 260 } 261 262 h4->rx_skb->dev = (void *) hu->hdev; 263 bt_cb(h4->rx_skb)->pkt_type = type; 264 } 265 266 return count; 267 } 268 269 static struct sk_buff *h4_dequeue(struct hci_uart *hu) 270 { 271 struct h4_struct *h4 = hu->priv; 272 return skb_dequeue(&h4->txq); 273 } 274 275 static struct hci_uart_proto h4p = { 276 .id = HCI_UART_H4, 277 .open = h4_open, 278 .close = h4_close, 279 .recv = h4_recv, 280 .enqueue = h4_enqueue, 281 .dequeue = h4_dequeue, 282 .flush = h4_flush, 283 }; 284 285 int h4_init(void) 286 { 287 int err = hci_uart_register_proto(&h4p); 288 289 if (!err) 290 BT_INFO("HCI H4 protocol initialized"); 291 else 292 BT_ERR("HCI H4 protocol registration failed"); 293 294 return err; 295 } 296 297 int h4_deinit(void) 298 { 299 return hci_uart_unregister_proto(&h4p); 300 } 301