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 along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #include "qemu-common.h"
  22 #include "qemu-char.h"
  23 #include "sysemu.h"
  24 #include "net.h"
  25 #include "hw/bt.h"
  26
  27 #define VHCI_DEV        "/dev/vhci"
  28 #define VHCI_UDEV       "/dev/hci_vhci"
  29
  30 struct bt_vhci_s {
  31     int fd;
  32     struct HCIInfo *info;
  33
  34     uint8_t hdr[4096];
  35     int len;
  36 };
  37
  38 static void vhci_read(void *opaque)
  39 {
  40     struct bt_vhci_s *s = (struct bt_vhci_s *) opaque;
  41     uint8_t *pkt;
  42     int pktlen;
  43
  44     /* Seems that we can't read only the header first and then the amount
  45      * of data indicated in the header because Linux will discard everything
  46      * that's not been read in one go.  */
  47     s->len = read(s->fd, s->hdr, sizeof(s->hdr));
  48
  49     if (s->len < 0) {
  50         fprintf(stderr, "qemu: error %i reading the PDU\n", errno);
  51         return;
  52     }
  53
  54     pkt = s->hdr;
  55     while (s->len --)
  56         switch (*pkt ++) {
  57         case HCI_COMMAND_PKT:
  58             if (s->len < 3)
  59                 goto bad_pkt;
  60
  61             pktlen = MIN(pkt[2] + 3, s->len);
  62             s->info->cmd_send(s->info, pkt, pktlen);
  63             s->len -= pktlen;
  64             pkt += pktlen;
  65             break;
  66
  67         case HCI_ACLDATA_PKT:
  68             if (s->len < 4)
  69                 goto bad_pkt;
  70
  71             pktlen = MIN(((pkt[3] << 8) | pkt[2]) + 4, s->len);
  72             s->info->acl_send(s->info, pkt, pktlen);
  73             s->len -= pktlen;
  74             pkt += pktlen;
  75             break;
  76
  77         case HCI_SCODATA_PKT:
  78             if (s->len < 3)
  79                 goto bad_pkt;
  80
  81             pktlen = MIN(pkt[2] + 3, s->len);
  82             s->info->sco_send(s->info, pkt, pktlen);
  83             s->len -= pktlen;
  84             pkt += pktlen;
  85             break;
  86
  87         default:
  88         bad_pkt:
  89             fprintf(stderr, "qemu: bad HCI packet type %02x\n", pkt[-1]);
  90         }
  91 }
  92
  93 static void vhci_host_send(void *opaque,
  94                 int type, const uint8_t *data, int len)
  95 {
  96     struct bt_vhci_s *s = (struct bt_vhci_s *) opaque;
  97 #if 0
  98     uint8_t pkt = type;
  99     struct iovec iv[2];
 100
 101     iv[0].iov_base = &pkt;
 102     iv[0].iov_len  = 1;
 103     iv[1].iov_base = (void *) data;
 104     iv[1].iov_len  = len;
 105
 106     while (writev(s->fd, iv, 2) < 0)
 107         if (errno != EAGAIN && errno != EINTR) {
 108             fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
 109                             errno);
 110             return;
 111         }
 112 #else
 113     /* Apparently VHCI wants us to write everything in one chunk :-(  */
 114     static uint8_t buf[4096];
 115
 116     buf[0] = type;
 117     memcpy(buf + 1, data, len);
 118
 119     while (write(s->fd, buf, len + 1) < 0)
 120         if (errno != EAGAIN && errno != EINTR) {
 121             fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
 122                             errno);
 123             return;
 124         }
 125 #endif
 126 }
 127
 128 static void vhci_out_hci_packet_event(void *opaque,
 129                 const uint8_t *data, int len)
 130 {
 131     vhci_host_send(opaque, HCI_EVENT_PKT, data, len);
 132 }
 133
 134 static void vhci_out_hci_packet_acl(void *opaque,
 135                 const uint8_t *data, int len)
 136 {
 137     vhci_host_send(opaque, HCI_ACLDATA_PKT, data, len);
 138 }
 139
 140 void bt_vhci_init(struct HCIInfo *info)
 141 {
 142     struct bt_vhci_s *s;
 143     int err[2];
 144     int fd;
 145
 146     fd = open(VHCI_DEV, O_RDWR);
 147     err[0] = errno;
 148     if (fd < 0) {
 149         fd = open(VHCI_UDEV, O_RDWR);
 150         err[1] = errno;
 151     }
 152
 153     if (fd < 0) {
 154         fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 155                         VHCI_DEV, strerror(err[0]), err[0]);
 156         fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 157                         VHCI_UDEV, strerror(err[1]), err[1]);
 158         exit(-1);
 159     }
 160
 161     s = qemu_mallocz(sizeof(struct bt_vhci_s));
 162     s->fd = fd;
 163     s->info = info ?: qemu_next_hci();
 164     s->info->opaque = s;
 165     s->info->evt_recv = vhci_out_hci_packet_event;
 166     s->info->acl_recv = vhci_out_hci_packet_acl;
 167
 168     qemu_set_fd_handler(s->fd, vhci_read, NULL, s);
 169 }