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