| 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 | #include <asm/unaligned.h> |
| 44 | |
| 45 | #include <net/bluetooth/bluetooth.h> |
| 46 | #include <net/bluetooth/hci_core.h> |
| 47 | |
| 48 | #include "hci_uart.h" |
| 49 | |
| 50 | struct h4_struct { |
| 51 | struct sk_buff *rx_skb; |
| 52 | struct sk_buff_head txq; |
| 53 | }; |
| 54 | |
| 55 | /* Initialize protocol */ |
| 56 | static int h4_open(struct hci_uart *hu) |
| 57 | { |
| 58 | struct h4_struct *h4; |
| 59 | |
| 60 | BT_DBG("hu %p", hu); |
| 61 | |
| 62 | h4 = kzalloc(sizeof(*h4), GFP_KERNEL); |
| 63 | if (!h4) |
| 64 | return -ENOMEM; |
| 65 | |
| 66 | skb_queue_head_init(&h4->txq); |
| 67 | |
| 68 | hu->priv = h4; |
| 69 | return 0; |
| 70 | } |
| 71 | |
| 72 | /* Flush protocol data */ |
| 73 | static int h4_flush(struct hci_uart *hu) |
| 74 | { |
| 75 | struct h4_struct *h4 = hu->priv; |
| 76 | |
| 77 | BT_DBG("hu %p", hu); |
| 78 | |
| 79 | skb_queue_purge(&h4->txq); |
| 80 | |
| 81 | return 0; |
| 82 | } |
| 83 | |
| 84 | /* Close protocol */ |
| 85 | static int h4_close(struct hci_uart *hu) |
| 86 | { |
| 87 | struct h4_struct *h4 = hu->priv; |
| 88 | |
| 89 | hu->priv = NULL; |
| 90 | |
| 91 | BT_DBG("hu %p", hu); |
| 92 | |
| 93 | skb_queue_purge(&h4->txq); |
| 94 | |
| 95 | kfree_skb(h4->rx_skb); |
| 96 | |
| 97 | hu->priv = NULL; |
| 98 | kfree(h4); |
| 99 | |
| 100 | return 0; |
| 101 | } |
| 102 | |
| 103 | /* Enqueue frame for transmittion (padding, crc, etc) */ |
| 104 | static int h4_enqueue(struct hci_uart *hu, struct sk_buff *skb) |
| 105 | { |
| 106 | struct h4_struct *h4 = hu->priv; |
| 107 | |
| 108 | BT_DBG("hu %p skb %p", hu, skb); |
| 109 | |
| 110 | /* Prepend skb with frame type */ |
| 111 | memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1); |
| 112 | skb_queue_tail(&h4->txq, skb); |
| 113 | |
| 114 | return 0; |
| 115 | } |
| 116 | |
| 117 | static const struct h4_recv_pkt h4_recv_pkts[] = { |
| 118 | { H4_RECV_ACL, .recv = hci_recv_frame }, |
| 119 | { H4_RECV_SCO, .recv = hci_recv_frame }, |
| 120 | { H4_RECV_EVENT, .recv = hci_recv_frame }, |
| 121 | }; |
| 122 | |
| 123 | /* Recv data */ |
| 124 | static int h4_recv(struct hci_uart *hu, const void *data, int count) |
| 125 | { |
| 126 | struct h4_struct *h4 = hu->priv; |
| 127 | |
| 128 | if (!test_bit(HCI_UART_REGISTERED, &hu->flags)) |
| 129 | return -EUNATCH; |
| 130 | |
| 131 | h4->rx_skb = h4_recv_buf(hu->hdev, h4->rx_skb, data, count, |
| 132 | h4_recv_pkts, ARRAY_SIZE(h4_recv_pkts)); |
| 133 | if (IS_ERR(h4->rx_skb)) { |
| 134 | int err = PTR_ERR(h4->rx_skb); |
| 135 | BT_ERR("%s: Frame reassembly failed (%d)", hu->hdev->name, err); |
| 136 | h4->rx_skb = NULL; |
| 137 | return err; |
| 138 | } |
| 139 | |
| 140 | return count; |
| 141 | } |
| 142 | |
| 143 | static struct sk_buff *h4_dequeue(struct hci_uart *hu) |
| 144 | { |
| 145 | struct h4_struct *h4 = hu->priv; |
| 146 | return skb_dequeue(&h4->txq); |
| 147 | } |
| 148 | |
| 149 | static const struct hci_uart_proto h4p = { |
| 150 | .id = HCI_UART_H4, |
| 151 | .name = "H4", |
| 152 | .open = h4_open, |
| 153 | .close = h4_close, |
| 154 | .recv = h4_recv, |
| 155 | .enqueue = h4_enqueue, |
| 156 | .dequeue = h4_dequeue, |
| 157 | .flush = h4_flush, |
| 158 | }; |
| 159 | |
| 160 | int __init h4_init(void) |
| 161 | { |
| 162 | return hci_uart_register_proto(&h4p); |
| 163 | } |
| 164 | |
| 165 | int __exit h4_deinit(void) |
| 166 | { |
| 167 | return hci_uart_unregister_proto(&h4p); |
| 168 | } |
| 169 | |
| 170 | struct sk_buff *h4_recv_buf(struct hci_dev *hdev, struct sk_buff *skb, |
| 171 | const unsigned char *buffer, int count, |
| 172 | const struct h4_recv_pkt *pkts, int pkts_count) |
| 173 | { |
| 174 | while (count) { |
| 175 | int i, len; |
| 176 | |
| 177 | if (!skb) { |
| 178 | for (i = 0; i < pkts_count; i++) { |
| 179 | if (buffer[0] != (&pkts[i])->type) |
| 180 | continue; |
| 181 | |
| 182 | skb = bt_skb_alloc((&pkts[i])->maxlen, |
| 183 | GFP_ATOMIC); |
| 184 | if (!skb) |
| 185 | return ERR_PTR(-ENOMEM); |
| 186 | |
| 187 | hci_skb_pkt_type(skb) = (&pkts[i])->type; |
| 188 | hci_skb_expect(skb) = (&pkts[i])->hlen; |
| 189 | break; |
| 190 | } |
| 191 | |
| 192 | /* Check for invalid packet type */ |
| 193 | if (!skb) |
| 194 | return ERR_PTR(-EILSEQ); |
| 195 | |
| 196 | count -= 1; |
| 197 | buffer += 1; |
| 198 | } |
| 199 | |
| 200 | len = min_t(uint, hci_skb_expect(skb) - skb->len, count); |
| 201 | memcpy(skb_put(skb, len), buffer, len); |
| 202 | |
| 203 | count -= len; |
| 204 | buffer += len; |
| 205 | |
| 206 | /* Check for partial packet */ |
| 207 | if (skb->len < hci_skb_expect(skb)) |
| 208 | continue; |
| 209 | |
| 210 | for (i = 0; i < pkts_count; i++) { |
| 211 | if (hci_skb_pkt_type(skb) == (&pkts[i])->type) |
| 212 | break; |
| 213 | } |
| 214 | |
| 215 | if (i >= pkts_count) { |
| 216 | kfree_skb(skb); |
| 217 | return ERR_PTR(-EILSEQ); |
| 218 | } |
| 219 | |
| 220 | if (skb->len == (&pkts[i])->hlen) { |
| 221 | u16 dlen; |
| 222 | |
| 223 | switch ((&pkts[i])->lsize) { |
| 224 | case 0: |
| 225 | /* No variable data length */ |
| 226 | dlen = 0; |
| 227 | break; |
| 228 | case 1: |
| 229 | /* Single octet variable length */ |
| 230 | dlen = skb->data[(&pkts[i])->loff]; |
| 231 | hci_skb_expect(skb) += dlen; |
| 232 | |
| 233 | if (skb_tailroom(skb) < dlen) { |
| 234 | kfree_skb(skb); |
| 235 | return ERR_PTR(-EMSGSIZE); |
| 236 | } |
| 237 | break; |
| 238 | case 2: |
| 239 | /* Double octet variable length */ |
| 240 | dlen = get_unaligned_le16(skb->data + |
| 241 | (&pkts[i])->loff); |
| 242 | hci_skb_expect(skb) += dlen; |
| 243 | |
| 244 | if (skb_tailroom(skb) < dlen) { |
| 245 | kfree_skb(skb); |
| 246 | return ERR_PTR(-EMSGSIZE); |
| 247 | } |
| 248 | break; |
| 249 | default: |
| 250 | /* Unsupported variable length */ |
| 251 | kfree_skb(skb); |
| 252 | return ERR_PTR(-EILSEQ); |
| 253 | } |
| 254 | |
| 255 | if (!dlen) { |
| 256 | /* No more data, complete frame */ |
| 257 | (&pkts[i])->recv(hdev, skb); |
| 258 | skb = NULL; |
| 259 | } |
| 260 | } else { |
| 261 | /* Complete frame */ |
| 262 | (&pkts[i])->recv(hdev, skb); |
| 263 | skb = NULL; |
| 264 | } |
| 265 | } |
| 266 | |
| 267 | return skb; |
| 268 | } |
| 269 | EXPORT_SYMBOL_GPL(h4_recv_buf); |