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 = kzalloc(sizeof(*h4), GFP_ATOMIC); 80 if (!h4) 81 return -ENOMEM; 82 83 skb_queue_head_init(&h4->txq); 84 85 hu->priv = h4; 86 return 0; 87 } 88 89 /* Flush protocol data */ 90 static int h4_flush(struct hci_uart *hu) 91 { 92 struct h4_struct *h4 = hu->priv; 93 94 BT_DBG("hu %p", hu); 95 96 skb_queue_purge(&h4->txq); 97 98 return 0; 99 } 100 101 /* Close protocol */ 102 static int h4_close(struct hci_uart *hu) 103 { 104 struct h4_struct *h4 = hu->priv; 105 106 hu->priv = NULL; 107 108 BT_DBG("hu %p", hu); 109 110 skb_queue_purge(&h4->txq); 111 112 if (h4->rx_skb) 113 kfree_skb(h4->rx_skb); 114 115 hu->priv = NULL; 116 kfree(h4); 117 118 return 0; 119 } 120 121 /* Enqueue frame for transmittion (padding, crc, etc) */ 122 static int h4_enqueue(struct hci_uart *hu, struct sk_buff *skb) 123 { 124 struct h4_struct *h4 = hu->priv; 125 126 BT_DBG("hu %p skb %p", hu, skb); 127 128 /* Prepend skb with frame type */ 129 memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1); 130 skb_queue_tail(&h4->txq, skb); 131 132 return 0; 133 } 134 135 static inline int h4_check_data_len(struct h4_struct *h4, int len) 136 { 137 register int room = skb_tailroom(h4->rx_skb); 138 139 BT_DBG("len %d room %d", len, room); 140 141 if (!len) { 142 hci_recv_frame(h4->rx_skb); 143 } else if (len > room) { 144 BT_ERR("Data length is too large"); 145 kfree_skb(h4->rx_skb); 146 } else { 147 h4->rx_state = H4_W4_DATA; 148 h4->rx_count = len; 149 return len; 150 } 151 152 h4->rx_state = H4_W4_PACKET_TYPE; 153 h4->rx_skb = NULL; 154 h4->rx_count = 0; 155 156 return 0; 157 } 158 159 /* Recv data */ 160 static int h4_recv(struct hci_uart *hu, void *data, int count) 161 { 162 struct h4_struct *h4 = hu->priv; 163 register char *ptr; 164 struct hci_event_hdr *eh; 165 struct hci_acl_hdr *ah; 166 struct hci_sco_hdr *sh; 167 register int len, type, dlen; 168 169 BT_DBG("hu %p count %d rx_state %ld rx_count %ld", 170 hu, count, h4->rx_state, h4->rx_count); 171 172 ptr = data; 173 while (count) { 174 if (h4->rx_count) { 175 len = min_t(unsigned int, h4->rx_count, count); 176 memcpy(skb_put(h4->rx_skb, len), ptr, len); 177 h4->rx_count -= len; count -= len; ptr += len; 178 179 if (h4->rx_count) 180 continue; 181 182 switch (h4->rx_state) { 183 case H4_W4_DATA: 184 BT_DBG("Complete data"); 185 186 hci_recv_frame(h4->rx_skb); 187 188 h4->rx_state = H4_W4_PACKET_TYPE; 189 h4->rx_skb = NULL; 190 continue; 191 192 case H4_W4_EVENT_HDR: 193 eh = (struct hci_event_hdr *) h4->rx_skb->data; 194 195 BT_DBG("Event header: evt 0x%2.2x plen %d", eh->evt, eh->plen); 196 197 h4_check_data_len(h4, eh->plen); 198 continue; 199 200 case H4_W4_ACL_HDR: 201 ah = (struct hci_acl_hdr *) h4->rx_skb->data; 202 dlen = __le16_to_cpu(ah->dlen); 203 204 BT_DBG("ACL header: dlen %d", dlen); 205 206 h4_check_data_len(h4, dlen); 207 continue; 208 209 case H4_W4_SCO_HDR: 210 sh = (struct hci_sco_hdr *) h4->rx_skb->data; 211 212 BT_DBG("SCO header: dlen %d", sh->dlen); 213 214 h4_check_data_len(h4, sh->dlen); 215 continue; 216 } 217 } 218 219 /* H4_W4_PACKET_TYPE */ 220 switch (*ptr) { 221 case HCI_EVENT_PKT: 222 BT_DBG("Event packet"); 223 h4->rx_state = H4_W4_EVENT_HDR; 224 h4->rx_count = HCI_EVENT_HDR_SIZE; 225 type = HCI_EVENT_PKT; 226 break; 227 228 case HCI_ACLDATA_PKT: 229 BT_DBG("ACL packet"); 230 h4->rx_state = H4_W4_ACL_HDR; 231 h4->rx_count = HCI_ACL_HDR_SIZE; 232 type = HCI_ACLDATA_PKT; 233 break; 234 235 case HCI_SCODATA_PKT: 236 BT_DBG("SCO packet"); 237 h4->rx_state = H4_W4_SCO_HDR; 238 h4->rx_count = HCI_SCO_HDR_SIZE; 239 type = HCI_SCODATA_PKT; 240 break; 241 242 default: 243 BT_ERR("Unknown HCI packet type %2.2x", (__u8)*ptr); 244 hu->hdev->stat.err_rx++; 245 ptr++; count--; 246 continue; 247 }; 248 249 ptr++; count--; 250 251 /* Allocate packet */ 252 h4->rx_skb = bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC); 253 if (!h4->rx_skb) { 254 BT_ERR("Can't allocate mem for new packet"); 255 h4->rx_state = H4_W4_PACKET_TYPE; 256 h4->rx_count = 0; 257 return 0; 258 } 259 260 h4->rx_skb->dev = (void *) hu->hdev; 261 bt_cb(h4->rx_skb)->pkt_type = type; 262 } 263 264 return count; 265 } 266 267 static struct sk_buff *h4_dequeue(struct hci_uart *hu) 268 { 269 struct h4_struct *h4 = hu->priv; 270 return skb_dequeue(&h4->txq); 271 } 272 273 static struct hci_uart_proto h4p = { 274 .id = HCI_UART_H4, 275 .open = h4_open, 276 .close = h4_close, 277 .recv = h4_recv, 278 .enqueue = h4_enqueue, 279 .dequeue = h4_dequeue, 280 .flush = h4_flush, 281 }; 282 283 int h4_init(void) 284 { 285 int err = hci_uart_register_proto(&h4p); 286 287 if (!err) 288 BT_INFO("HCI H4 protocol initialized"); 289 else 290 BT_ERR("HCI H4 protocol registration failed"); 291 292 return err; 293 } 294 295 int h4_deinit(void) 296 { 297 return hci_uart_unregister_proto(&h4p); 298 } 299