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