bt-vhci.c

   1 /*
   2  * Support for host VHCIs inside qemu scatternets.
   3  *
   4  * Copyright (C) 2008 Andrzej Zaborowski  <balrog@zabor.org>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; either version 2 or
   9  * (at your option) version 3 of the License.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  19  * MA 02111-1307 USA
  20  */
  21
  22 #include "qemu-common.h"
  23 #include "qemu-char.h"
  24 #include "sysemu.h"
  25 #include "net.h"
  26 #include "hw/bt.h"
  27
  28 #define VHCI_DEV        "/dev/vhci"
  29 #define VHCI_UDEV       "/dev/hci_vhci"
  30
  31 struct bt_vhci_s {
  32     int fd;
  33     struct HCIInfo *info;
  34
  35     uint8_t hdr[4096];
  36     int len;
  37 };
  38
  39 static void vhci_read(void *opaque)
  40 {
  41     struct bt_vhci_s *s = (struct bt_vhci_s *) opaque;
  42     uint8_t *pkt;
  43     int pktlen;
  44
  45     /* Seems that we can't read only the header first and then the amount
  46      * of data indicated in the header because Linux will discard everything
  47      * that's not been read in one go.  */
  48     s->len = read(s->fd, s->hdr, sizeof(s->hdr));
  49
  50     if (s->len < 0) {
  51         fprintf(stderr, "qemu: error %i reading the PDU\n", errno);
  52         return;
  53     }
  54
  55     pkt = s->hdr;
  56     while (s->len --)
  57         switch (*pkt ++) {
  58         case HCI_COMMAND_PKT:
  59             if (s->len < 3)
  60                 goto bad_pkt;
  61
  62             pktlen = MIN(pkt[2] + 3, s->len);
  63             s->info->cmd_send(s->info, pkt, pktlen);
  64             s->len -= pktlen;
  65             pkt += pktlen;
  66             break;
  67
  68         case HCI_ACLDATA_PKT:
  69             if (s->len < 4)
  70                 goto bad_pkt;
  71
  72             pktlen = MIN(((pkt[3] << 8) | pkt[2]) + 4, s->len);
  73             s->info->acl_send(s->info, pkt, pktlen);
  74             s->len -= pktlen;
  75             pkt += pktlen;
  76             break;
  77
  78         case HCI_SCODATA_PKT:
  79             if (s->len < 3)
  80                 goto bad_pkt;
  81
  82             pktlen = MIN(pkt[2] + 3, s->len);
  83             s->info->sco_send(s->info, pkt, pktlen);
  84             s->len -= pktlen;
  85             pkt += pktlen;
  86             break;
  87
  88         default:
  89         bad_pkt:
  90             fprintf(stderr, "qemu: bad HCI packet type %02x\n", pkt[-1]);
  91         }
  92 }
  93
  94 static void vhci_host_send(void *opaque,
  95                 int type, const uint8_t *data, int len)
  96 {
  97     struct bt_vhci_s *s = (struct bt_vhci_s *) opaque;
  98 #if 0
  99     uint8_t pkt = type;
 100     struct iovec iv[2];
 101
 102     iv[0].iov_base = &pkt;
 103     iv[0].iov_len  = 1;
 104     iv[1].iov_base = (void *) data;
 105     iv[1].iov_len  = len;
 106
 107     while (writev(s->fd, iv, 2) < 0)
 108         if (errno != EAGAIN && errno != EINTR) {
 109             fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
 110                             errno);
 111             return;
 112         }
 113 #else
 114     /* Apparently VHCI wants us to write everything in one chunk :-(  */
 115     static uint8_t buf[4096];
 116
 117     buf[0] = type;
 118     memcpy(buf + 1, data, len);
 119
 120     while (write(s->fd, buf, len + 1) < 0)
 121         if (errno != EAGAIN && errno != EINTR) {
 122             fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
 123                             errno);
 124             return;
 125         }
 126 #endif
 127 }
 128
 129 static void vhci_out_hci_packet_event(void *opaque,
 130                 const uint8_t *data, int len)
 131 {
 132     vhci_host_send(opaque, HCI_EVENT_PKT, data, len);
 133 }
 134
 135 static void vhci_out_hci_packet_acl(void *opaque,
 136                 const uint8_t *data, int len)
 137 {
 138     vhci_host_send(opaque, HCI_ACLDATA_PKT, data, len);
 139 }
 140
 141 void bt_vhci_init(struct HCIInfo *info)
 142 {
 143     struct bt_vhci_s *s;
 144     int err[2];
 145     int fd;
 146
 147     fd = open(VHCI_DEV, O_RDWR);
 148     err[0] = errno;
 149     if (fd < 0) {
 150         fd = open(VHCI_UDEV, O_RDWR);
 151         err[1] = errno;
 152     }
 153
 154     if (fd < 0) {
 155         fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 156                         VHCI_DEV, strerror(err[0]), err[0]);
 157         fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 158                         VHCI_UDEV, strerror(err[1]), err[1]);
 159         exit(-1);
 160     }
 161
 162     s = qemu_mallocz(sizeof(struct bt_vhci_s));
 163     s->fd = fd;
 164     s->info = info ?: qemu_next_hci();
 165     s->info->opaque = s;
 166     s->info->evt_recv = vhci_out_hci_packet_event;
 167     s->info->acl_recv = vhci_out_hci_packet_acl;
 168
 169     qemu_set_fd_handler(s->fd, vhci_read, 0, s);
 170 }