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