int
gusb_close(gpsdevh *dh)
{
garmin_usb_packet scratch;
memset(&scratch, 0, sizeof(scratch));
switch (receive_state) {
case rs_frombulk:
gusb_cmd_get(&scratch, sizeof(scratch));
break;
default:
break;
}
gusb_llops->llop_close(dh);
return 1;
#if BOOGER
garmin_usb_packet scratch = {0};
abort();
switch (receive_state) {
case rs_frombulk:
gusb_cmd_get(dh, &scratch, sizeof(scratch));
break;
}
return 1;
#endif
}
void
gusb_syncup(void)
{
static int unit_number;
static const char oinit[12] =
{0, 0, 0, 0, GUSB_SESSION_START, 0, 0, 0, 0, 0, 0, 0};
garmin_usb_packet iresp;
int i;
/*
* This is our first communication with the unit.
*/
receive_state = rs_fromintr;
for(i = 0; i < 25; i++) {
le_write16(&iresp.gusb_pkt.pkt_id, 0);
le_write32(&iresp.gusb_pkt.datasz, 0);
le_write32(&iresp.gusb_pkt.databuf, 0);
gusb_cmd_send((const garmin_usb_packet *) oinit, sizeof(oinit));
gusb_cmd_get(&iresp, sizeof(iresp));
if ((le_read16(iresp.gusb_pkt.pkt_id) == GUSB_SESSION_ACK) &&
(le_read32(iresp.gusb_pkt.datasz) == 4)) {
unsigned serial_number = le_read32(iresp.gusb_pkt.databuf);
garmin_unit_info[unit_number].serial_number = serial_number;
gusb_id_unit(&garmin_unit_info[unit_number]);
unit_number++;
return;
}
}
fatal("Unable to establish USB syncup\n");
}
void
gusb_id_unit(struct garmin_unit_info *gu)
{
static const char oid[12] =
{20, 0, 0, 0, 0xfe, 0, 0, 0, 0, 0, 0, 0};
garmin_usb_packet iresp;
int i;
gusb_cmd_send((garmin_usb_packet *)oid, sizeof(oid));
for (i = 0; i < 25; i++) {
iresp.gusb_pkt.type = 0;
if (gusb_cmd_get(&iresp, sizeof(iresp)) < 0) {
return;
}
if (le_read16(iresp.gusb_pkt.pkt_id) == 0xff) {
gu->product_identifier = xstrdup((char *) iresp.gusb_pkt.databuf+4);
gu->unit_id = le_read16(iresp.gusb_pkt.databuf+0);
gu->unit_version = le_read16(iresp.gusb_pkt.databuf+2);
}
/*
* My goodnesss, this is fragile. During command syncup,
* we need to know if we're at the end. The 0xfd packet
* is promised by Garmin engineering to be the last.
*/
if (le_read16(iresp.gusb_pkt.pkt_id) == 0xfd) return;
}
fatal("Unable to sync with Garmin USB device in %d attempts.", i);
}
/*
* Return values are:
* Negative on error.
* 1 if read success - even if empty packet.
*/
int32 GPS_Packet_Read_usb(gpsdevh *dh, GPS_PPacket *packet, int eat_bulk)
{
int32 n;
int32 payload_size;
garmin_usb_packet pkt;
memset(&pkt, 0, sizeof(pkt));
do_over:
n = gusb_cmd_get(&pkt, sizeof(pkt));
if ( n < 0 ) {
/*
* We (probably) used to have a GPS and it went away
* while we were speaking with it. Perhaps batteries
* died or it was unplugged or something.
*/
gps_errno = PROTOCOL_ERROR;
return n;
}
/*
* This is a horrible hack for 276/296. This family sometimes
* switches between bulk and interrupt on EVERY packet. Rather
* than bother all the callers with that bit of unpleasantness,
* silently consume zero byte "switch back to intr" packets here.
*
* The one caller that doesn't want this hidden is device discovery
* in the A000 handler.
*/
if ((n == 0) && eat_bulk) {
goto do_over;
}
/*
* Populate members of serial packet from USB packet. The
* copy here seems wasteful, but teaching all the callers about
* a structure with the "data" member being in a different place
* (Since the protocol packets was badly exposed in the core
* design of jeeps) is even more painful.
*/
(*packet)->type = le_read16(&pkt.gusb_pkt.pkt_id);
payload_size = le_read32(&pkt.gusb_pkt.datasz);
if (payload_size<0 || payload_size>MAX_GPS_PACKET_SIZE)
{
GPS_Error("GPS_Packet_Read_usb: Bad payload size %d", payload_size);
gps_errno = FRAMING_ERROR;
return 0;
}
(*packet)->n = payload_size;
memcpy((*packet)->data, &pkt.gusb_pkt.databuf, payload_size);
return 1;
}
/*
* This was a function of great joy to discover...and even greater to maintain.
*
* It turns out that as of 5/2006, every Garmin USB product has a problem
* where the device does not reset the data toggles after a configuration
* set. After a reset, the toggles both match. So we tear through the
* conversation and life is good. Unfortunately, the second time through,
* if we had an odd number of transactions in the previous conversation,
* we send a configuration set and reset the toggle on the HCI but the
* toggle on the device's end of the pipe is now out of whack which means
* that the subsequent transaction will hang.
*
* This isn't a problem in Windows since the configuration set is done only
* once there.
*
* This code has been tested in loops of 1000 cycles on Linux and OS/X and
* it seems to cure this at a mere cost of complexity and startup time. I'll
* be delighted when all the firmware gets revved and updated and we can
* remove this.
*
* 9/2008 But wait, there's more. The very toggle reset that we *had* to
* implement in 2006 to make non-Windows OSes work actually locks up verion
* 2.70 of the Venture HC. On that model, the second product request
* (you know, the one that we *use*, locks that device's protocol stack
* after the RET2INTR that immediately follows the REQBLK (and why is it
* telling us to go into bulk mode followed by an immeidate EOF, anyway?)
* that follows the request for product ID. 100% reproducible on Mac and
* Linux. Of course, we don't see this on the Windows system becuase
* we don't have to jump through hooops to clear the spec-violating out
* of state toggles there becuase those systems see only one configuration
* set ever.
*
* Grrrr!
*/
unsigned
gusb_reset_toggles(void)
{
static const char oinit[12] =
{0, 0, 0, 0, GUSB_SESSION_START, 0, 0, 0, 0, 0, 0, 0};
static const char oid[12] =
{20, 0, 0, 0, 0xfe, 0, 0, 0, 0, 0, 0, 0};
garmin_usb_packet iresp;
int t;
unsigned rv = 0;
/* Start off with three session starts.
* #1 resets the bulk out toggle. It may not make it to the device.
* #2 resets the the intr in toggle. It will make it to the device
* since #1 reset the the bulk out toggle. The device will
* respond on the intr in pipe which will clear its toggle.
* #3 actually starts the session now that the above are both clear.
*/
gusb_cmd_send((const garmin_usb_packet *) oinit, sizeof(oinit));
gusb_cmd_send((const garmin_usb_packet *) oinit, sizeof(oinit));
gusb_cmd_send((const garmin_usb_packet *) oinit, sizeof(oinit));
t = 10;
while(1) {
le_write16(&iresp.gusb_pkt.pkt_id, 0);
le_write32(&iresp.gusb_pkt.datasz, 0);
le_write32(&iresp.gusb_pkt.databuf, 0);
gusb_cmd_get(&iresp, sizeof(iresp));
if ((le_read16(iresp.gusb_pkt.pkt_id) == GUSB_SESSION_ACK) &&
(le_read32(iresp.gusb_pkt.datasz) == 4)) {
break;
}
if (t-- <= 0) {
fatal("Could not start session in a reasonable number of tries.\n");
}
}
/*
* Now that the bulk out and intr in packets are good, we send
* a product ID. On devices that respond totally on the intr
* pipe, this does nothing interesting, but on devices that respon
* on the bulk pipe this will reset the toggles on the bulk in.
*/
t = 10;
gusb_cmd_send((const garmin_usb_packet *) oid, sizeof(oid));
while(1) {
le_write16(&iresp.gusb_pkt.pkt_id, 0);
le_write32(&iresp.gusb_pkt.datasz, 0);
le_write32(&iresp.gusb_pkt.databuf, 0);
gusb_cmd_get(&iresp, sizeof(iresp));
if (le_read16(iresp.gusb_pkt.pkt_id) == 0xff) {
rv = le_read16(iresp.gusb_pkt.databuf+0);
}
if (le_read16(iresp.gusb_pkt.pkt_id) == 0xfd) return rv;
if (t-- <= 0) {
fatal("Could not start session in a reasonable number of tries.\n");
}
}
return 0;
}
/*
* Return values are:
* Negative on error.
* 1 if read success - even if empty packet.
*/
int32 GPS_Packet_Read_usb(gpsdevh *dh, GPS_PPacket *packet, int eat_bulk)
{
int32 n;
int32 payload_size;
garmin_usb_packet pkt;
memset(&pkt, 0, sizeof(pkt));
do_over:
n = gusb_cmd_get(&pkt, sizeof(pkt));
if ( n < 0 ) {
/*
* We (probably) used to have a GPS and it went away
* while we were speaking with it. Perhaps batteries
* died or it was unplugged or something.
*/
gps_errno = PROTOCOL_ERROR;
return n;
}
/*
* This is a horrible hack for 276/296. This family sometimes
* switches between bulk and interrupt on EVERY packet. Rather
* than bother all the callers with that bit of unpleasantness,
* silently consume zero byte "switch back to intr" packets here.
*
* The one caller that doesn't want this hidden is device discovery
* in the A000 handler.
*/
if ((n == 0) && eat_bulk) {
goto do_over;
}
/* We sometimes get corrupted packets during a track log transfer
* where the first byte in a packet is lost, causing all remaining
* bytes in this packet to be shifted. So far, this has only been
* observed on a Forerunner 305 (both on Linux and Windows). The
* cause is unknown, but it seems to be timing dependent.
* We try to detect the corruption mainly by checking reserved bytes
* 3 and 7 which normally should be 0, the remaining comparisons are
* only sanity checks and they alone could also trigger in case of
* valid packets. Note: We can't detect corrupted packets with an ID
* or length that's a multiple of 256, but such corrupted packets
* haven't been observed so far.
*/
if (gps_save_id == 484
&& pkt.gusb_pkt.type == 0 && pkt.gusb_pkt.reserved1 == 0
&& pkt.gusb_pkt.reserved2 == 0 && pkt.gusb_pkt.reserved3 != 0
&& pkt.gusb_pkt.pkt_id[0] <= 4 && pkt.gusb_pkt.pkt_id[1] == 0
&& pkt.gusb_pkt.reserved6 == 0 && pkt.gusb_pkt.reserved7 != 0) {
memmove(&pkt.dbuf[1], &pkt.dbuf[0], sizeof(pkt) - 1);
pkt.gusb_pkt.type = 20;
}
/*
* Populate members of serial packet from USB packet. The
* copy here seems wasteful, but teaching all the callers about
* a structure with the "data" member being in a different place
* (Since the protocol packets was badly exposed in the core
* design of jeeps) is even more painful.
*/
(*packet)->type = le_read16(&pkt.gusb_pkt.pkt_id);
payload_size = le_read32(&pkt.gusb_pkt.datasz);
if (payload_size<0 || payload_size>MAX_GPS_PACKET_SIZE)
{
/* If you get this, the packet might have been corrupted
* by the unit. Have a look at the corruption detection
* code above.
*/
GPS_Error("GPS_Packet_Read_usb: Bad payload size %d", payload_size);
gps_errno = FRAMING_ERROR;
return 0;
}
(*packet)->n = payload_size;
memcpy((*packet)->data, &pkt.gusb_pkt.databuf, payload_size);
return 1;
}
