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 #include <sys/uio.h>
  29
  30 #define VHCI_DEV        "/dev/vhci"
  31 #define VHCI_UDEV       "/dev/hci_vhci"
  32
  33 struct bt_vhci_s {
  34     int fd;
  35     struct HCIInfo *info;
  36
  37     uint8_t hdr[4096];
  38     int len;
  39 };
  40
  41 static void vhci_read(void *opaque)
  42 {
  43     struct bt_vhci_s *s = (struct bt_vhci_s *) opaque;
  44     uint8_t *pkt;
  45     int pktlen;
  46
  47     /* Seems that we can't read only the header first and then the amount
  48      * of data indicated in the header because Linux will discard everything
  49      * that's not been read in one go.  */
  50     s->len = read(s->fd, s->hdr, sizeof(s->hdr));
  51
  52     if (s->len < 0) {
  53         fprintf(stderr, "qemu: error %i reading the PDU\n", errno);
  54         return;
  55     }
  56
  57     pkt = s->hdr;
  58     while (s->len --)
  59         switch (*pkt ++) {
  60         case HCI_COMMAND_PKT:
  61             if (s->len < 3)
  62                 goto bad_pkt;
  63
  64             pktlen = MIN(pkt[2] + 3, s->len);
  65             s->info->cmd_send(s->info, pkt, pktlen);
  66             s->len -= pktlen;
  67             pkt += pktlen;
  68             break;
  69
  70         case HCI_ACLDATA_PKT:
  71             if (s->len < 4)
  72                 goto bad_pkt;
  73
  74             pktlen = MIN(((pkt[3] << 8) | pkt[2]) + 4, s->len);
  75             s->info->acl_send(s->info, pkt, pktlen);
  76             s->len -= pktlen;
  77             pkt += pktlen;
  78             break;
  79
  80         case HCI_SCODATA_PKT:
  81             if (s->len < 3)
  82                 goto bad_pkt;
  83
  84             pktlen = MIN(pkt[2] + 3, s->len);
  85             s->info->sco_send(s->info, pkt, pktlen);
  86             s->len -= pktlen;
  87             pkt += pktlen;
  88             break;
  89
  90         default:
  91         bad_pkt:
  92             fprintf(stderr, "qemu: bad HCI packet type %02x\n", pkt[-1]);
  93         }
  94 }
  95
  96 static void vhci_host_send(void *opaque,
  97                 int type, const uint8_t *data, int len)
  98 {
  99     struct bt_vhci_s *s = (struct bt_vhci_s *) opaque;
 100 #if 0
 101     uint8_t pkt = type;
 102     struct iovec iv[2];
 103
 104     iv[0].iov_base = &pkt;
 105     iv[0].iov_len  = 1;
 106     iv[1].iov_base = (void *) data;
 107     iv[1].iov_len  = len;
 108
 109     while (writev(s->fd, iv, 2) < 0)
 110         if (errno != EAGAIN && errno != EINTR) {
 111             fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
 112                             errno);
 113             return;
 114         }
 115 #else
 116     /* Apparently VHCI wants us to write everything in one chunk :-(  */
 117     static uint8_t buf[4096];
 118
 119     buf[0] = type;
 120     memcpy(buf + 1, data, len);
 121
 122     while (write(s->fd, buf, len + 1) < 0)
 123         if (errno != EAGAIN && errno != EINTR) {
 124             fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
 125                             errno);
 126             return;
 127         }
 128 #endif
 129 }
 130
 131 static void vhci_out_hci_packet_event(void *opaque,
 132                 const uint8_t *data, int len)
 133 {
 134     vhci_host_send(opaque, HCI_EVENT_PKT, data, len);
 135 }
 136
 137 static void vhci_out_hci_packet_acl(void *opaque,
 138                 const uint8_t *data, int len)
 139 {
 140     vhci_host_send(opaque, HCI_ACLDATA_PKT, data, len);
 141 }
 142
 143 void bt_vhci_init(struct HCIInfo *info)
 144 {
 145     struct bt_vhci_s *s;
 146     int err[2];
 147     int fd;
 148
 149     fd = open(VHCI_DEV, O_RDWR);
 150     err[0] = errno;
 151     if (fd < 0) {
 152         fd = open(VHCI_UDEV, O_RDWR);
 153         err[1] = errno;
 154     }
 155
 156     if (fd < 0) {
 157         fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 158                         VHCI_DEV, strerror(err[0]), err[0]);
 159         fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 160                         VHCI_UDEV, strerror(err[1]), err[1]);
 161         exit(-1);
 162     }
 163
 164     s = qemu_mallocz(sizeof(struct bt_vhci_s));
 165     s->fd = fd;
 166     s->info = info ?: qemu_next_hci();
 167     s->info->opaque = s;
 168     s->info->evt_recv = vhci_out_hci_packet_event;
 169     s->info->acl_recv = vhci_out_hci_packet_acl;
 170
 171     qemu_set_fd_handler(s->fd, vhci_read, 0, s);
 172 }