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garmin_gps.c
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1 /*
2  * Garmin GPS driver
3  *
4  * Copyright (C) 2006-2011 Hermann Kneissel [email protected]
5  *
6  * The latest version of the driver can be found at
7  * http://sourceforge.net/projects/garmin-gps/
8  *
9  * This driver has been derived from v2.1 of the visor driver.
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111 USA
24  */
25 
26 #include <linux/kernel.h>
27 #include <linux/errno.h>
28 #include <linux/init.h>
29 #include <linux/slab.h>
30 #include <linux/timer.h>
31 #include <linux/tty.h>
32 #include <linux/tty_driver.h>
33 #include <linux/tty_flip.h>
34 #include <linux/module.h>
35 #include <linux/spinlock.h>
36 #include <linux/uaccess.h>
37 #include <linux/atomic.h>
38 #include <linux/usb.h>
39 #include <linux/usb/serial.h>
40 
41 /* the mode to be set when the port ist opened */
42 static int initial_mode = 1;
43 
44 #define GARMIN_VENDOR_ID 0x091E
45 
46 /*
47  * Version Information
48  */
49 
50 #define VERSION_MAJOR 0
51 #define VERSION_MINOR 36
52 
53 #define _STR(s) #s
54 #define _DRIVER_VERSION(a, b) "v" _STR(a) "." _STR(b)
55 #define DRIVER_VERSION _DRIVER_VERSION(VERSION_MAJOR, VERSION_MINOR)
56 #define DRIVER_AUTHOR "hermann kneissel"
57 #define DRIVER_DESC "garmin gps driver"
58 
59 /* error codes returned by the driver */
60 #define EINVPKT 1000 /* invalid packet structure */
61 
62 
63 /* size of the header of a packet using the usb protocol */
64 #define GARMIN_PKTHDR_LENGTH 12
65 
66 /* max. possible size of a packet using the serial protocol */
67 #define MAX_SERIAL_PKT_SIZ (3 + 255 + 3)
68 
69 /* max. possible size of a packet with worst case stuffing */
70 #define MAX_SERIAL_PKT_SIZ_STUFFED (MAX_SERIAL_PKT_SIZ + 256)
71 
72 /* size of a buffer able to hold a complete (no stuffing) packet
73  * (the document protocol does not contain packets with a larger
74  * size, but in theory a packet may be 64k+12 bytes - if in
75  * later protocol versions larger packet sizes occur, this value
76  * should be increased accordingly, so the input buffer is always
77  * large enough the store a complete packet inclusive header) */
78 #define GPS_IN_BUFSIZ (GARMIN_PKTHDR_LENGTH+MAX_SERIAL_PKT_SIZ)
79 
80 /* size of a buffer able to hold a complete (incl. stuffing) packet */
81 #define GPS_OUT_BUFSIZ (GARMIN_PKTHDR_LENGTH+MAX_SERIAL_PKT_SIZ_STUFFED)
82 
83 /* where to place the packet id of a serial packet, so we can
84  * prepend the usb-packet header without the need to move the
85  * packets data */
86 #define GSP_INITIAL_OFFSET (GARMIN_PKTHDR_LENGTH-2)
87 
88 /* max. size of incoming private packets (header+1 param) */
89 #define PRIVPKTSIZ (GARMIN_PKTHDR_LENGTH+4)
90 
91 #define GARMIN_LAYERID_TRANSPORT 0
92 #define GARMIN_LAYERID_APPL 20
93 /* our own layer-id to use for some control mechanisms */
94 #define GARMIN_LAYERID_PRIVATE 0x01106E4B
95 
96 #define GARMIN_PKTID_PVT_DATA 51
97 #define GARMIN_PKTID_L001_COMMAND_DATA 10
98 
99 #define CMND_ABORT_TRANSFER 0
100 
101 /* packet ids used in private layer */
102 #define PRIV_PKTID_SET_DEBUG 1
103 #define PRIV_PKTID_SET_MODE 2
104 #define PRIV_PKTID_INFO_REQ 3
105 #define PRIV_PKTID_INFO_RESP 4
106 #define PRIV_PKTID_RESET_REQ 5
107 #define PRIV_PKTID_SET_DEF_MODE 6
108 
109 
110 #define ETX 0x03
111 #define DLE 0x10
112 #define ACK 0x06
113 #define NAK 0x15
114 
115 /* structure used to queue incoming packets */
116 struct garmin_packet {
117  struct list_head list;
118  int seq;
119  /* the real size of the data array, always > 0 */
120  int size;
121  __u8 data[1];
122 };
123 
124 /* structure used to keep the current state of the driver */
125 struct garmin_data {
126  __u8 state;
127  __u16 flags;
128  __u8 mode;
129  __u8 count;
130  __u8 pkt_id;
131  __u32 serial_num;
132  struct timer_list timer;
133  struct usb_serial_port *port;
134  int seq_counter;
135  int insize;
136  int outsize;
137  __u8 inbuffer [GPS_IN_BUFSIZ]; /* tty -> usb */
138  __u8 outbuffer[GPS_OUT_BUFSIZ]; /* usb -> tty */
139  __u8 privpkt[4*6];
140  spinlock_t lock;
141  struct list_head pktlist;
142 };
143 
144 
145 #define STATE_NEW 0
146 #define STATE_INITIAL_DELAY 1
147 #define STATE_TIMEOUT 2
148 #define STATE_SESSION_REQ1 3
149 #define STATE_SESSION_REQ2 4
150 #define STATE_ACTIVE 5
151 
152 #define STATE_RESET 8
153 #define STATE_DISCONNECTED 9
154 #define STATE_WAIT_TTY_ACK 10
155 #define STATE_GSP_WAIT_DATA 11
156 
157 #define MODE_NATIVE 0
158 #define MODE_GARMIN_SERIAL 1
159 
160 /* Flags used in garmin_data.flags: */
161 #define FLAGS_SESSION_REPLY_MASK 0x00C0
162 #define FLAGS_SESSION_REPLY1_SEEN 0x0080
163 #define FLAGS_SESSION_REPLY2_SEEN 0x0040
164 #define FLAGS_BULK_IN_ACTIVE 0x0020
165 #define FLAGS_BULK_IN_RESTART 0x0010
166 #define FLAGS_THROTTLED 0x0008
167 #define APP_REQ_SEEN 0x0004
168 #define APP_RESP_SEEN 0x0002
169 #define CLEAR_HALT_REQUIRED 0x0001
170 
171 #define FLAGS_QUEUING 0x0100
172 #define FLAGS_DROP_DATA 0x0800
173 
174 #define FLAGS_GSP_SKIP 0x1000
175 #define FLAGS_GSP_DLESEEN 0x2000
176 
177 
178 
179 
180 
181 
182 /* function prototypes */
183 static int gsp_next_packet(struct garmin_data *garmin_data_p);
184 static int garmin_write_bulk(struct usb_serial_port *port,
185  const unsigned char *buf, int count,
186  int dismiss_ack);
187 
188 /* some special packets to be send or received */
189 static unsigned char const GARMIN_START_SESSION_REQ[]
190  = { 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0 };
191 static unsigned char const GARMIN_START_SESSION_REPLY[]
192  = { 0, 0, 0, 0, 6, 0, 0, 0, 4, 0, 0, 0 };
193 static unsigned char const GARMIN_BULK_IN_AVAIL_REPLY[]
194  = { 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0 };
195 static unsigned char const GARMIN_APP_LAYER_REPLY[]
196  = { 0x14, 0, 0, 0 };
197 static unsigned char const GARMIN_START_PVT_REQ[]
198  = { 20, 0, 0, 0, 10, 0, 0, 0, 2, 0, 0, 0, 49, 0 };
199 static unsigned char const GARMIN_STOP_PVT_REQ[]
200  = { 20, 0, 0, 0, 10, 0, 0, 0, 2, 0, 0, 0, 50, 0 };
201 static unsigned char const GARMIN_STOP_TRANSFER_REQ[]
202  = { 20, 0, 0, 0, 10, 0, 0, 0, 2, 0, 0, 0, 0, 0 };
203 static unsigned char const GARMIN_STOP_TRANSFER_REQ_V2[]
204  = { 20, 0, 0, 0, 10, 0, 0, 0, 1, 0, 0, 0, 0 };
205 static unsigned char const PRIVATE_REQ[]
206  = { 0x4B, 0x6E, 0x10, 0x01, 0xFF, 0, 0, 0, 0xFF, 0, 0, 0 };
207 
208 
209 
210 static const struct usb_device_id id_table[] = {
211  /* the same device id seems to be used by all
212  usb enabled GPS devices */
213  { USB_DEVICE(GARMIN_VENDOR_ID, 3) },
214  { } /* Terminating entry */
215 };
216 MODULE_DEVICE_TABLE(usb, id_table);
217 
218 
219 static inline int getLayerId(const __u8 *usbPacket)
220 {
221  return __le32_to_cpup((__le32 *)(usbPacket));
222 }
223 
224 static inline int getPacketId(const __u8 *usbPacket)
225 {
226  return __le32_to_cpup((__le32 *)(usbPacket+4));
227 }
228 
229 static inline int getDataLength(const __u8 *usbPacket)
230 {
231  return __le32_to_cpup((__le32 *)(usbPacket+8));
232 }
233 
234 
235 /*
236  * check if the usb-packet in buf contains an abort-transfer command.
237  * (if yes, all queued data will be dropped)
238  */
239 static inline int isAbortTrfCmnd(const unsigned char *buf)
240 {
241  if (0 == memcmp(buf, GARMIN_STOP_TRANSFER_REQ,
242  sizeof(GARMIN_STOP_TRANSFER_REQ)) ||
243  0 == memcmp(buf, GARMIN_STOP_TRANSFER_REQ_V2,
244  sizeof(GARMIN_STOP_TRANSFER_REQ_V2)))
245  return 1;
246  else
247  return 0;
248 }
249 
250 
251 
252 static void send_to_tty(struct usb_serial_port *port,
253  char *data, unsigned int actual_length)
254 {
255  struct tty_struct *tty = tty_port_tty_get(&port->port);
256 
257  if (tty && actual_length) {
258  usb_serial_debug_data(&port->dev, __func__, actual_length, data);
259  tty_insert_flip_string(tty, data, actual_length);
260  tty_flip_buffer_push(tty);
261  }
262  tty_kref_put(tty);
263 }
264 
265 
266 /******************************************************************************
267  * packet queue handling
268  ******************************************************************************/
269 
270 /*
271  * queue a received (usb-)packet for later processing
272  */
273 static int pkt_add(struct garmin_data *garmin_data_p,
274  unsigned char *data, unsigned int data_length)
275 {
276  int state = 0;
277  int result = 0;
278  unsigned long flags;
279  struct garmin_packet *pkt;
280 
281  /* process only packets containg data ... */
282  if (data_length) {
283  pkt = kmalloc(sizeof(struct garmin_packet)+data_length,
284  GFP_ATOMIC);
285  if (pkt == NULL) {
286  dev_err(&garmin_data_p->port->dev, "out of memory\n");
287  return 0;
288  }
289  pkt->size = data_length;
290  memcpy(pkt->data, data, data_length);
291 
292  spin_lock_irqsave(&garmin_data_p->lock, flags);
293  garmin_data_p->flags |= FLAGS_QUEUING;
294  result = list_empty(&garmin_data_p->pktlist);
295  pkt->seq = garmin_data_p->seq_counter++;
296  list_add_tail(&pkt->list, &garmin_data_p->pktlist);
297  state = garmin_data_p->state;
298  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
299 
300  dev_dbg(&garmin_data_p->port->dev,
301  "%s - added: pkt: %d - %d bytes\n", __func__,
302  pkt->seq, data_length);
303 
304  /* in serial mode, if someone is waiting for data from
305  the device, convert and send the next packet to tty. */
306  if (result && (state == STATE_GSP_WAIT_DATA))
307  gsp_next_packet(garmin_data_p);
308  }
309  return result;
310 }
311 
312 
313 /* get the next pending packet */
314 static struct garmin_packet *pkt_pop(struct garmin_data *garmin_data_p)
315 {
316  unsigned long flags;
317  struct garmin_packet *result = NULL;
318 
319  spin_lock_irqsave(&garmin_data_p->lock, flags);
320  if (!list_empty(&garmin_data_p->pktlist)) {
321  result = (struct garmin_packet *)garmin_data_p->pktlist.next;
322  list_del(&result->list);
323  }
324  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
325  return result;
326 }
327 
328 
329 /* free up all queued data */
330 static void pkt_clear(struct garmin_data *garmin_data_p)
331 {
332  unsigned long flags;
333  struct garmin_packet *result = NULL;
334 
335  spin_lock_irqsave(&garmin_data_p->lock, flags);
336  while (!list_empty(&garmin_data_p->pktlist)) {
337  result = (struct garmin_packet *)garmin_data_p->pktlist.next;
338  list_del(&result->list);
339  kfree(result);
340  }
341  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
342 }
343 
344 
345 /******************************************************************************
346  * garmin serial protocol handling handling
347  ******************************************************************************/
348 
349 /* send an ack packet back to the tty */
350 static int gsp_send_ack(struct garmin_data *garmin_data_p, __u8 pkt_id)
351 {
352  __u8 pkt[10];
353  __u8 cksum = 0;
354  __u8 *ptr = pkt;
355  unsigned l = 0;
356 
357  dev_dbg(&garmin_data_p->port->dev, "%s - pkt-id: 0x%X.\n", __func__,
358  0xFF & pkt_id);
359 
360  *ptr++ = DLE;
361  *ptr++ = ACK;
362  cksum += ACK;
363 
364  *ptr++ = 2;
365  cksum += 2;
366 
367  *ptr++ = pkt_id;
368  cksum += pkt_id;
369 
370  if (pkt_id == DLE)
371  *ptr++ = DLE;
372 
373  *ptr++ = 0;
374  *ptr++ = 0xFF & (-cksum);
375  *ptr++ = DLE;
376  *ptr++ = ETX;
377 
378  l = ptr-pkt;
379 
380  send_to_tty(garmin_data_p->port, pkt, l);
381  return 0;
382 }
383 
384 
385 
386 /*
387  * called for a complete packet received from tty layer
388  *
389  * the complete packet (pktid ... cksum) is in garmin_data_p->inbuf starting
390  * at GSP_INITIAL_OFFSET.
391  *
392  * count - number of bytes in the input buffer including space reserved for
393  * the usb header: GSP_INITIAL_OFFSET + number of bytes in packet
394  * (including pkt-id, data-length a. cksum)
395  */
396 static int gsp_rec_packet(struct garmin_data *garmin_data_p, int count)
397 {
398  struct device *dev = &garmin_data_p->port->dev;
399  unsigned long flags;
400  const __u8 *recpkt = garmin_data_p->inbuffer+GSP_INITIAL_OFFSET;
401  __le32 *usbdata = (__le32 *) garmin_data_p->inbuffer;
402  int cksum = 0;
403  int n = 0;
404  int pktid = recpkt[0];
405  int size = recpkt[1];
406 
407  usb_serial_debug_data(&garmin_data_p->port->dev, __func__,
408  count-GSP_INITIAL_OFFSET, recpkt);
409 
410  if (size != (count-GSP_INITIAL_OFFSET-3)) {
411  dev_dbg(dev, "%s - invalid size, expected %d bytes, got %d\n",
412  __func__, size, (count-GSP_INITIAL_OFFSET-3));
413  return -EINVPKT;
414  }
415 
416  cksum += *recpkt++;
417  cksum += *recpkt++;
418 
419  /* sanity check, remove after test ... */
420  if ((__u8 *)&(usbdata[3]) != recpkt) {
421  dev_dbg(dev, "%s - ptr mismatch %p - %p\n", __func__,
422  &(usbdata[4]), recpkt);
423  return -EINVPKT;
424  }
425 
426  while (n < size) {
427  cksum += *recpkt++;
428  n++;
429  }
430 
431  if ((0xff & (cksum + *recpkt)) != 0) {
432  dev_dbg(dev, "%s - invalid checksum, expected %02x, got %02x\n",
433  __func__, 0xff & -cksum, 0xff & *recpkt);
434  return -EINVPKT;
435  }
436 
437  usbdata[0] = __cpu_to_le32(GARMIN_LAYERID_APPL);
438  usbdata[1] = __cpu_to_le32(pktid);
439  usbdata[2] = __cpu_to_le32(size);
440 
441  garmin_write_bulk(garmin_data_p->port, garmin_data_p->inbuffer,
442  GARMIN_PKTHDR_LENGTH+size, 0);
443 
444  /* if this was an abort-transfer command, flush all
445  queued data. */
446  if (isAbortTrfCmnd(garmin_data_p->inbuffer)) {
447  spin_lock_irqsave(&garmin_data_p->lock, flags);
448  garmin_data_p->flags |= FLAGS_DROP_DATA;
449  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
450  pkt_clear(garmin_data_p);
451  }
452 
453  return count;
454 }
455 
456 
457 
458 /*
459  * Called for data received from tty
460  *
461  * buf contains the data read, it may span more than one packet or even
462  * incomplete packets
463  *
464  * input record should be a serial-record, but it may not be complete.
465  * Copy it into our local buffer, until an etx is seen (or an error
466  * occurs).
467  * Once the record is complete, convert into a usb packet and send it
468  * to the bulk pipe, send an ack back to the tty.
469  *
470  * If the input is an ack, just send the last queued packet to the
471  * tty layer.
472  *
473  * if the input is an abort command, drop all queued data.
474  */
475 
476 static int gsp_receive(struct garmin_data *garmin_data_p,
477  const unsigned char *buf, int count)
478 {
479  struct device *dev = &garmin_data_p->port->dev;
480  unsigned long flags;
481  int offs = 0;
482  int ack_or_nak_seen = 0;
483  __u8 *dest;
484  int size;
485  /* dleSeen: set if last byte read was a DLE */
486  int dleSeen;
487  /* skip: if set, skip incoming data until possible start of
488  * new packet
489  */
490  int skip;
491  __u8 data;
492 
493  spin_lock_irqsave(&garmin_data_p->lock, flags);
494  dest = garmin_data_p->inbuffer;
495  size = garmin_data_p->insize;
496  dleSeen = garmin_data_p->flags & FLAGS_GSP_DLESEEN;
497  skip = garmin_data_p->flags & FLAGS_GSP_SKIP;
498  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
499 
500  /* dev_dbg(dev, "%s - dle=%d skip=%d size=%d count=%d\n",
501  __func__, dleSeen, skip, size, count); */
502 
503  if (size == 0)
504  size = GSP_INITIAL_OFFSET;
505 
506  while (offs < count) {
507 
508  data = *(buf+offs);
509  offs++;
510 
511  if (data == DLE) {
512  if (skip) { /* start of a new pkt */
513  skip = 0;
514  size = GSP_INITIAL_OFFSET;
515  dleSeen = 1;
516  } else if (dleSeen) {
517  dest[size++] = data;
518  dleSeen = 0;
519  } else {
520  dleSeen = 1;
521  }
522  } else if (data == ETX) {
523  if (dleSeen) {
524  /* packet complete */
525 
526  data = dest[GSP_INITIAL_OFFSET];
527 
528  if (data == ACK) {
529  ack_or_nak_seen = ACK;
530  dev_dbg(dev, "ACK packet complete.\n");
531  } else if (data == NAK) {
532  ack_or_nak_seen = NAK;
533  dev_dbg(dev, "NAK packet complete.\n");
534  } else {
535  dev_dbg(dev, "packet complete - id=0x%X.\n",
536  0xFF & data);
537  gsp_rec_packet(garmin_data_p, size);
538  }
539 
540  skip = 1;
541  size = GSP_INITIAL_OFFSET;
542  dleSeen = 0;
543  } else {
544  dest[size++] = data;
545  }
546  } else if (!skip) {
547 
548  if (dleSeen) {
549  size = GSP_INITIAL_OFFSET;
550  dleSeen = 0;
551  }
552 
553  dest[size++] = data;
554  }
555 
556  if (size >= GPS_IN_BUFSIZ) {
557  dev_dbg(dev, "%s - packet too large.\n", __func__);
558  skip = 1;
559  size = GSP_INITIAL_OFFSET;
560  dleSeen = 0;
561  }
562  }
563 
564  spin_lock_irqsave(&garmin_data_p->lock, flags);
565 
566  garmin_data_p->insize = size;
567 
568  /* copy flags back to structure */
569  if (skip)
570  garmin_data_p->flags |= FLAGS_GSP_SKIP;
571  else
572  garmin_data_p->flags &= ~FLAGS_GSP_SKIP;
573 
574  if (dleSeen)
575  garmin_data_p->flags |= FLAGS_GSP_DLESEEN;
576  else
577  garmin_data_p->flags &= ~FLAGS_GSP_DLESEEN;
578 
579  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
580 
581  if (ack_or_nak_seen) {
582  if (gsp_next_packet(garmin_data_p) > 0)
583  garmin_data_p->state = STATE_ACTIVE;
584  else
585  garmin_data_p->state = STATE_GSP_WAIT_DATA;
586  }
587  return count;
588 }
589 
590 
591 
592 /*
593  * Sends a usb packet to the tty
594  *
595  * Assumes, that all packages and at an usb-packet boundary.
596  *
597  * return <0 on error, 0 if packet is incomplete or > 0 if packet was sent
598  */
599 static int gsp_send(struct garmin_data *garmin_data_p,
600  const unsigned char *buf, int count)
601 {
602  struct device *dev = &garmin_data_p->port->dev;
603  const unsigned char *src;
604  unsigned char *dst;
605  int pktid = 0;
606  int datalen = 0;
607  int cksum = 0;
608  int i = 0;
609  int k;
610 
611  dev_dbg(dev, "%s - state %d - %d bytes.\n", __func__,
612  garmin_data_p->state, count);
613 
614  k = garmin_data_p->outsize;
615  if ((k+count) > GPS_OUT_BUFSIZ) {
616  dev_dbg(dev, "packet too large\n");
617  garmin_data_p->outsize = 0;
618  return -4;
619  }
620 
621  memcpy(garmin_data_p->outbuffer+k, buf, count);
622  k += count;
623  garmin_data_p->outsize = k;
624 
625  if (k >= GARMIN_PKTHDR_LENGTH) {
626  pktid = getPacketId(garmin_data_p->outbuffer);
627  datalen = getDataLength(garmin_data_p->outbuffer);
628  i = GARMIN_PKTHDR_LENGTH + datalen;
629  if (k < i)
630  return 0;
631  } else {
632  return 0;
633  }
634 
635  dev_dbg(dev, "%s - %d bytes in buffer, %d bytes in pkt.\n", __func__, k, i);
636 
637  /* garmin_data_p->outbuffer now contains a complete packet */
638 
639  usb_serial_debug_data(&garmin_data_p->port->dev, __func__, k,
640  garmin_data_p->outbuffer);
641 
642  garmin_data_p->outsize = 0;
643 
644  if (GARMIN_LAYERID_APPL != getLayerId(garmin_data_p->outbuffer)) {
645  dev_dbg(dev, "not an application packet (%d)\n",
646  getLayerId(garmin_data_p->outbuffer));
647  return -1;
648  }
649 
650  if (pktid > 255) {
651  dev_dbg(dev, "packet-id %d too large\n", pktid);
652  return -2;
653  }
654 
655  if (datalen > 255) {
656  dev_dbg(dev, "packet-size %d too large\n", datalen);
657  return -3;
658  }
659 
660  /* the serial protocol should be able to handle this packet */
661 
662  k = 0;
663  src = garmin_data_p->outbuffer+GARMIN_PKTHDR_LENGTH;
664  for (i = 0; i < datalen; i++) {
665  if (*src++ == DLE)
666  k++;
667  }
668 
669  src = garmin_data_p->outbuffer+GARMIN_PKTHDR_LENGTH;
670  if (k > (GARMIN_PKTHDR_LENGTH-2)) {
671  /* can't add stuffing DLEs in place, move data to end
672  of buffer ... */
673  dst = garmin_data_p->outbuffer+GPS_OUT_BUFSIZ-datalen;
674  memcpy(dst, src, datalen);
675  src = dst;
676  }
677 
678  dst = garmin_data_p->outbuffer;
679 
680  *dst++ = DLE;
681  *dst++ = pktid;
682  cksum += pktid;
683  *dst++ = datalen;
684  cksum += datalen;
685  if (datalen == DLE)
686  *dst++ = DLE;
687 
688  for (i = 0; i < datalen; i++) {
689  __u8 c = *src++;
690  *dst++ = c;
691  cksum += c;
692  if (c == DLE)
693  *dst++ = DLE;
694  }
695 
696  cksum = 0xFF & -cksum;
697  *dst++ = cksum;
698  if (cksum == DLE)
699  *dst++ = DLE;
700  *dst++ = DLE;
701  *dst++ = ETX;
702 
703  i = dst-garmin_data_p->outbuffer;
704 
705  send_to_tty(garmin_data_p->port, garmin_data_p->outbuffer, i);
706 
707  garmin_data_p->pkt_id = pktid;
708  garmin_data_p->state = STATE_WAIT_TTY_ACK;
709 
710  return i;
711 }
712 
713 
714 /*
715  * Process the next pending data packet - if there is one
716  */
717 static int gsp_next_packet(struct garmin_data *garmin_data_p)
718 {
719  int result = 0;
720  struct garmin_packet *pkt = NULL;
721 
722  while ((pkt = pkt_pop(garmin_data_p)) != NULL) {
723  dev_dbg(&garmin_data_p->port->dev, "%s - next pkt: %d\n", __func__, pkt->seq);
724  result = gsp_send(garmin_data_p, pkt->data, pkt->size);
725  if (result > 0) {
726  kfree(pkt);
727  return result;
728  }
729  kfree(pkt);
730  }
731  return result;
732 }
733 
734 
735 
736 /******************************************************************************
737  * garmin native mode
738  ******************************************************************************/
739 
740 
741 /*
742  * Called for data received from tty
743  *
744  * The input data is expected to be in garmin usb-packet format.
745  *
746  * buf contains the data read, it may span more than one packet
747  * or even incomplete packets
748  */
749 static int nat_receive(struct garmin_data *garmin_data_p,
750  const unsigned char *buf, int count)
751 {
752  unsigned long flags;
753  __u8 *dest;
754  int offs = 0;
755  int result = count;
756  int len;
757 
758  while (offs < count) {
759  /* if buffer contains header, copy rest of data */
760  if (garmin_data_p->insize >= GARMIN_PKTHDR_LENGTH)
761  len = GARMIN_PKTHDR_LENGTH
762  +getDataLength(garmin_data_p->inbuffer);
763  else
764  len = GARMIN_PKTHDR_LENGTH;
765 
766  if (len >= GPS_IN_BUFSIZ) {
767  /* seems to be an invalid packet, ignore rest
768  of input */
769  dev_dbg(&garmin_data_p->port->dev,
770  "%s - packet size too large: %d\n",
771  __func__, len);
772  garmin_data_p->insize = 0;
773  count = 0;
774  result = -EINVPKT;
775  } else {
776  len -= garmin_data_p->insize;
777  if (len > (count-offs))
778  len = (count-offs);
779  if (len > 0) {
780  dest = garmin_data_p->inbuffer
781  + garmin_data_p->insize;
782  memcpy(dest, buf+offs, len);
783  garmin_data_p->insize += len;
784  offs += len;
785  }
786  }
787 
788  /* do we have a complete packet ? */
789  if (garmin_data_p->insize >= GARMIN_PKTHDR_LENGTH) {
790  len = GARMIN_PKTHDR_LENGTH+
791  getDataLength(garmin_data_p->inbuffer);
792  if (garmin_data_p->insize >= len) {
793  garmin_write_bulk(garmin_data_p->port,
794  garmin_data_p->inbuffer,
795  len, 0);
796  garmin_data_p->insize = 0;
797 
798  /* if this was an abort-transfer command,
799  flush all queued data. */
800  if (isAbortTrfCmnd(garmin_data_p->inbuffer)) {
801  spin_lock_irqsave(&garmin_data_p->lock,
802  flags);
803  garmin_data_p->flags |= FLAGS_DROP_DATA;
804  spin_unlock_irqrestore(
805  &garmin_data_p->lock, flags);
806  pkt_clear(garmin_data_p);
807  }
808  }
809  }
810  }
811  return result;
812 }
813 
814 
815 /******************************************************************************
816  * private packets
817  ******************************************************************************/
818 
819 static void priv_status_resp(struct usb_serial_port *port)
820 {
821  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
822  __le32 *pkt = (__le32 *)garmin_data_p->privpkt;
823 
824  pkt[0] = __cpu_to_le32(GARMIN_LAYERID_PRIVATE);
825  pkt[1] = __cpu_to_le32(PRIV_PKTID_INFO_RESP);
826  pkt[2] = __cpu_to_le32(12);
827  pkt[3] = __cpu_to_le32(VERSION_MAJOR << 16 | VERSION_MINOR);
828  pkt[4] = __cpu_to_le32(garmin_data_p->mode);
829  pkt[5] = __cpu_to_le32(garmin_data_p->serial_num);
830 
831  send_to_tty(port, (__u8 *)pkt, 6 * 4);
832 }
833 
834 
835 /******************************************************************************
836  * Garmin specific driver functions
837  ******************************************************************************/
838 
839 static int process_resetdev_request(struct usb_serial_port *port)
840 {
841  unsigned long flags;
842  int status;
843  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
844 
845  spin_lock_irqsave(&garmin_data_p->lock, flags);
846  garmin_data_p->flags &= ~(CLEAR_HALT_REQUIRED);
847  garmin_data_p->state = STATE_RESET;
848  garmin_data_p->serial_num = 0;
849  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
850 
851  usb_kill_urb(port->interrupt_in_urb);
852  dev_dbg(&port->dev, "%s - usb_reset_device\n", __func__);
853  status = usb_reset_device(port->serial->dev);
854  if (status)
855  dev_dbg(&port->dev, "%s - usb_reset_device failed: %d\n",
856  __func__, status);
857  return status;
858 }
859 
860 
861 
862 /*
863  * clear all cached data
864  */
865 static int garmin_clear(struct garmin_data *garmin_data_p)
866 {
867  unsigned long flags;
868  int status = 0;
869 
870  /* flush all queued data */
871  pkt_clear(garmin_data_p);
872 
873  spin_lock_irqsave(&garmin_data_p->lock, flags);
874  garmin_data_p->insize = 0;
875  garmin_data_p->outsize = 0;
876  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
877 
878  return status;
879 }
880 
881 
882 static int garmin_init_session(struct usb_serial_port *port)
883 {
884  struct usb_serial *serial = port->serial;
885  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
886  int status = 0;
887  int i = 0;
888 
889  if (status == 0) {
890  usb_kill_urb(port->interrupt_in_urb);
891 
892  dev_dbg(&serial->dev->dev, "%s - adding interrupt input\n", __func__);
893  status = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
894  if (status)
895  dev_err(&serial->dev->dev,
896  "%s - failed submitting interrupt urb, error %d\n",
897  __func__, status);
898  }
899 
900  /*
901  * using the initialization method from gpsbabel. See comments in
902  * gpsbabel/jeeps/gpslibusb.c gusb_reset_toggles()
903  */
904  if (status == 0) {
905  dev_dbg(&serial->dev->dev, "%s - starting session ...\n", __func__);
906  garmin_data_p->state = STATE_ACTIVE;
907 
908  for (i = 0; i < 3; i++) {
909  status = garmin_write_bulk(port,
910  GARMIN_START_SESSION_REQ,
911  sizeof(GARMIN_START_SESSION_REQ), 0);
912 
913  if (status < 0)
914  break;
915  }
916 
917  if (status > 0)
918  status = 0;
919  }
920 
921  return status;
922 }
923 
924 
925 
926 static int garmin_open(struct tty_struct *tty, struct usb_serial_port *port)
927 {
928  unsigned long flags;
929  int status = 0;
930  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
931 
932  spin_lock_irqsave(&garmin_data_p->lock, flags);
933  garmin_data_p->mode = initial_mode;
934  garmin_data_p->count = 0;
935  garmin_data_p->flags &= FLAGS_SESSION_REPLY1_SEEN;
936  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
937 
938  /* shutdown any bulk reads that might be going on */
939  usb_kill_urb(port->write_urb);
940  usb_kill_urb(port->read_urb);
941 
942  if (garmin_data_p->state == STATE_RESET)
943  status = garmin_init_session(port);
944 
945  garmin_data_p->state = STATE_ACTIVE;
946  return status;
947 }
948 
949 
950 static void garmin_close(struct usb_serial_port *port)
951 {
952  struct usb_serial *serial = port->serial;
953  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
954 
955  dev_dbg(&port->dev, "%s - port %d - mode=%d state=%d flags=0x%X\n",
956  __func__, port->number, garmin_data_p->mode,
957  garmin_data_p->state, garmin_data_p->flags);
958 
959  if (!serial)
960  return;
961 
962  mutex_lock(&port->serial->disc_mutex);
963 
964  if (!port->serial->disconnected)
965  garmin_clear(garmin_data_p);
966 
967  /* shutdown our urbs */
968  usb_kill_urb(port->read_urb);
969  usb_kill_urb(port->write_urb);
970 
971  /* keep reset state so we know that we must start a new session */
972  if (garmin_data_p->state != STATE_RESET)
973  garmin_data_p->state = STATE_DISCONNECTED;
974 
975  mutex_unlock(&port->serial->disc_mutex);
976 }
977 
978 
979 static void garmin_write_bulk_callback(struct urb *urb)
980 {
981  struct usb_serial_port *port = urb->context;
982 
983  if (port) {
984  struct garmin_data *garmin_data_p =
985  usb_get_serial_port_data(port);
986 
987  if (GARMIN_LAYERID_APPL == getLayerId(urb->transfer_buffer)) {
988 
989  if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
990  gsp_send_ack(garmin_data_p,
991  ((__u8 *)urb->transfer_buffer)[4]);
992  }
993  }
994  usb_serial_port_softint(port);
995  }
996 
997  /* Ignore errors that resulted from garmin_write_bulk with
998  dismiss_ack = 1 */
999 
1000  /* free up the transfer buffer, as usb_free_urb() does not do this */
1001  kfree(urb->transfer_buffer);
1002 }
1003 
1004 
1005 static int garmin_write_bulk(struct usb_serial_port *port,
1006  const unsigned char *buf, int count,
1007  int dismiss_ack)
1008 {
1009  unsigned long flags;
1010  struct usb_serial *serial = port->serial;
1011  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1012  struct urb *urb;
1013  unsigned char *buffer;
1014  int status;
1015 
1016  spin_lock_irqsave(&garmin_data_p->lock, flags);
1017  garmin_data_p->flags &= ~FLAGS_DROP_DATA;
1018  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1019 
1020  buffer = kmalloc(count, GFP_ATOMIC);
1021  if (!buffer) {
1022  dev_err(&port->dev, "out of memory\n");
1023  return -ENOMEM;
1024  }
1025 
1026  urb = usb_alloc_urb(0, GFP_ATOMIC);
1027  if (!urb) {
1028  dev_err(&port->dev, "no more free urbs\n");
1029  kfree(buffer);
1030  return -ENOMEM;
1031  }
1032 
1033  memcpy(buffer, buf, count);
1034 
1035  usb_serial_debug_data(&port->dev, __func__, count, buffer);
1036 
1037  usb_fill_bulk_urb(urb, serial->dev,
1038  usb_sndbulkpipe(serial->dev,
1039  port->bulk_out_endpointAddress),
1040  buffer, count,
1041  garmin_write_bulk_callback,
1042  dismiss_ack ? NULL : port);
1043  urb->transfer_flags |= URB_ZERO_PACKET;
1044 
1045  if (GARMIN_LAYERID_APPL == getLayerId(buffer)) {
1046 
1047  spin_lock_irqsave(&garmin_data_p->lock, flags);
1048  garmin_data_p->flags |= APP_REQ_SEEN;
1049  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1050 
1051  if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
1052  pkt_clear(garmin_data_p);
1053  garmin_data_p->state = STATE_GSP_WAIT_DATA;
1054  }
1055  }
1056 
1057  /* send it down the pipe */
1058  status = usb_submit_urb(urb, GFP_ATOMIC);
1059  if (status) {
1060  dev_err(&port->dev,
1061  "%s - usb_submit_urb(write bulk) failed with status = %d\n",
1062  __func__, status);
1063  count = status;
1064  }
1065 
1066  /* we are done with this urb, so let the host driver
1067  * really free it when it is finished with it */
1068  usb_free_urb(urb);
1069 
1070  return count;
1071 }
1072 
1073 static int garmin_write(struct tty_struct *tty, struct usb_serial_port *port,
1074  const unsigned char *buf, int count)
1075 {
1076  struct device *dev = &port->dev;
1077  int pktid, pktsiz, len;
1078  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1079  __le32 *privpkt = (__le32 *)garmin_data_p->privpkt;
1080 
1081  usb_serial_debug_data(dev, __func__, count, buf);
1082 
1083  if (garmin_data_p->state == STATE_RESET)
1084  return -EIO;
1085 
1086  /* check for our private packets */
1087  if (count >= GARMIN_PKTHDR_LENGTH) {
1088  len = PRIVPKTSIZ;
1089  if (count < len)
1090  len = count;
1091 
1092  memcpy(garmin_data_p->privpkt, buf, len);
1093 
1094  pktsiz = getDataLength(garmin_data_p->privpkt);
1095  pktid = getPacketId(garmin_data_p->privpkt);
1096 
1097  if (count == (GARMIN_PKTHDR_LENGTH+pktsiz)
1098  && GARMIN_LAYERID_PRIVATE ==
1099  getLayerId(garmin_data_p->privpkt)) {
1100 
1101  dev_dbg(dev, "%s - processing private request %d\n",
1102  __func__, pktid);
1103 
1104  /* drop all unfinished transfers */
1105  garmin_clear(garmin_data_p);
1106 
1107  switch (pktid) {
1108  case PRIV_PKTID_SET_MODE:
1109  if (pktsiz != 4)
1110  return -EINVPKT;
1111  garmin_data_p->mode = __le32_to_cpu(privpkt[3]);
1112  dev_dbg(dev, "%s - mode set to %d\n",
1113  __func__, garmin_data_p->mode);
1114  break;
1115 
1116  case PRIV_PKTID_INFO_REQ:
1117  priv_status_resp(port);
1118  break;
1119 
1120  case PRIV_PKTID_RESET_REQ:
1121  process_resetdev_request(port);
1122  break;
1123 
1124  case PRIV_PKTID_SET_DEF_MODE:
1125  if (pktsiz != 4)
1126  return -EINVPKT;
1127  initial_mode = __le32_to_cpu(privpkt[3]);
1128  dev_dbg(dev, "%s - initial_mode set to %d\n",
1129  __func__,
1130  garmin_data_p->mode);
1131  break;
1132  }
1133  return count;
1134  }
1135  }
1136 
1137  if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
1138  return gsp_receive(garmin_data_p, buf, count);
1139  } else { /* MODE_NATIVE */
1140  return nat_receive(garmin_data_p, buf, count);
1141  }
1142 }
1143 
1144 
1145 static int garmin_write_room(struct tty_struct *tty)
1146 {
1147  struct usb_serial_port *port = tty->driver_data;
1148  /*
1149  * Report back the bytes currently available in the output buffer.
1150  */
1151  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1152  return GPS_OUT_BUFSIZ-garmin_data_p->outsize;
1153 }
1154 
1155 
1156 static void garmin_read_process(struct garmin_data *garmin_data_p,
1157  unsigned char *data, unsigned data_length,
1158  int bulk_data)
1159 {
1160  unsigned long flags;
1161 
1162  if (garmin_data_p->flags & FLAGS_DROP_DATA) {
1163  /* abort-transfer cmd is actice */
1164  dev_dbg(&garmin_data_p->port->dev, "%s - pkt dropped\n", __func__);
1165  } else if (garmin_data_p->state != STATE_DISCONNECTED &&
1166  garmin_data_p->state != STATE_RESET) {
1167 
1168  /* if throttling is active or postprecessing is required
1169  put the received data in the input queue, otherwise
1170  send it directly to the tty port */
1171  if (garmin_data_p->flags & FLAGS_QUEUING) {
1172  pkt_add(garmin_data_p, data, data_length);
1173  } else if (bulk_data ||
1174  getLayerId(data) == GARMIN_LAYERID_APPL) {
1175 
1176  spin_lock_irqsave(&garmin_data_p->lock, flags);
1177  garmin_data_p->flags |= APP_RESP_SEEN;
1178  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1179 
1180  if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
1181  pkt_add(garmin_data_p, data, data_length);
1182  } else {
1183  send_to_tty(garmin_data_p->port, data,
1184  data_length);
1185  }
1186  }
1187  /* ignore system layer packets ... */
1188  }
1189 }
1190 
1191 
1192 static void garmin_read_bulk_callback(struct urb *urb)
1193 {
1194  unsigned long flags;
1195  struct usb_serial_port *port = urb->context;
1196  struct usb_serial *serial = port->serial;
1197  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1198  unsigned char *data = urb->transfer_buffer;
1199  int status = urb->status;
1200  int retval;
1201 
1202  if (!serial) {
1203  dev_dbg(&urb->dev->dev, "%s - bad serial pointer, exiting\n", __func__);
1204  return;
1205  }
1206 
1207  if (status) {
1208  dev_dbg(&urb->dev->dev, "%s - nonzero read bulk status received: %d\n",
1209  __func__, status);
1210  return;
1211  }
1212 
1213  usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
1214 
1215  garmin_read_process(garmin_data_p, data, urb->actual_length, 1);
1216 
1217  if (urb->actual_length == 0 &&
1218  0 != (garmin_data_p->flags & FLAGS_BULK_IN_RESTART)) {
1219  spin_lock_irqsave(&garmin_data_p->lock, flags);
1220  garmin_data_p->flags &= ~FLAGS_BULK_IN_RESTART;
1221  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1222  retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1223  if (retval)
1224  dev_err(&port->dev,
1225  "%s - failed resubmitting read urb, error %d\n",
1226  __func__, retval);
1227  } else if (urb->actual_length > 0) {
1228  /* Continue trying to read until nothing more is received */
1229  if (0 == (garmin_data_p->flags & FLAGS_THROTTLED)) {
1230  retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1231  if (retval)
1232  dev_err(&port->dev,
1233  "%s - failed resubmitting read urb, error %d\n",
1234  __func__, retval);
1235  }
1236  } else {
1237  dev_dbg(&port->dev, "%s - end of bulk data\n", __func__);
1238  spin_lock_irqsave(&garmin_data_p->lock, flags);
1239  garmin_data_p->flags &= ~FLAGS_BULK_IN_ACTIVE;
1240  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1241  }
1242 }
1243 
1244 
1245 static void garmin_read_int_callback(struct urb *urb)
1246 {
1247  unsigned long flags;
1248  int retval;
1249  struct usb_serial_port *port = urb->context;
1250  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1251  unsigned char *data = urb->transfer_buffer;
1252  int status = urb->status;
1253 
1254  switch (status) {
1255  case 0:
1256  /* success */
1257  break;
1258  case -ECONNRESET:
1259  case -ENOENT:
1260  case -ESHUTDOWN:
1261  /* this urb is terminated, clean up */
1262  dev_dbg(&urb->dev->dev, "%s - urb shutting down with status: %d\n",
1263  __func__, status);
1264  return;
1265  default:
1266  dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n",
1267  __func__, status);
1268  return;
1269  }
1270 
1271  usb_serial_debug_data(&port->dev, __func__, urb->actual_length,
1272  urb->transfer_buffer);
1273 
1274  if (urb->actual_length == sizeof(GARMIN_BULK_IN_AVAIL_REPLY) &&
1275  0 == memcmp(data, GARMIN_BULK_IN_AVAIL_REPLY,
1276  sizeof(GARMIN_BULK_IN_AVAIL_REPLY))) {
1277 
1278  dev_dbg(&port->dev, "%s - bulk data available.\n", __func__);
1279 
1280  if (0 == (garmin_data_p->flags & FLAGS_BULK_IN_ACTIVE)) {
1281 
1282  /* bulk data available */
1283  retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1284  if (retval) {
1285  dev_err(&port->dev,
1286  "%s - failed submitting read urb, error %d\n",
1287  __func__, retval);
1288  } else {
1289  spin_lock_irqsave(&garmin_data_p->lock, flags);
1290  garmin_data_p->flags |= FLAGS_BULK_IN_ACTIVE;
1291  spin_unlock_irqrestore(&garmin_data_p->lock,
1292  flags);
1293  }
1294  } else {
1295  /* bulk-in transfer still active */
1296  spin_lock_irqsave(&garmin_data_p->lock, flags);
1297  garmin_data_p->flags |= FLAGS_BULK_IN_RESTART;
1298  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1299  }
1300 
1301  } else if (urb->actual_length == (4+sizeof(GARMIN_START_SESSION_REPLY))
1302  && 0 == memcmp(data, GARMIN_START_SESSION_REPLY,
1303  sizeof(GARMIN_START_SESSION_REPLY))) {
1304 
1305  spin_lock_irqsave(&garmin_data_p->lock, flags);
1306  garmin_data_p->flags |= FLAGS_SESSION_REPLY1_SEEN;
1307  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1308 
1309  /* save the serial number */
1310  garmin_data_p->serial_num = __le32_to_cpup(
1311  (__le32 *)(data+GARMIN_PKTHDR_LENGTH));
1312 
1313  dev_dbg(&port->dev, "%s - start-of-session reply seen - serial %u.\n",
1314  __func__, garmin_data_p->serial_num);
1315  }
1316 
1317  garmin_read_process(garmin_data_p, data, urb->actual_length, 0);
1318 
1319  retval = usb_submit_urb(urb, GFP_ATOMIC);
1320  if (retval)
1321  dev_err(&urb->dev->dev,
1322  "%s - Error %d submitting interrupt urb\n",
1323  __func__, retval);
1324 }
1325 
1326 
1327 /*
1328  * Sends the next queued packt to the tty port (garmin native mode only)
1329  * and then sets a timer to call itself again until all queued data
1330  * is sent.
1331  */
1332 static int garmin_flush_queue(struct garmin_data *garmin_data_p)
1333 {
1334  unsigned long flags;
1335  struct garmin_packet *pkt;
1336 
1337  if ((garmin_data_p->flags & FLAGS_THROTTLED) == 0) {
1338  pkt = pkt_pop(garmin_data_p);
1339  if (pkt != NULL) {
1340  send_to_tty(garmin_data_p->port, pkt->data, pkt->size);
1341  kfree(pkt);
1342  mod_timer(&garmin_data_p->timer, (1)+jiffies);
1343 
1344  } else {
1345  spin_lock_irqsave(&garmin_data_p->lock, flags);
1346  garmin_data_p->flags &= ~FLAGS_QUEUING;
1347  spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1348  }
1349  }
1350  return 0;
1351 }
1352 
1353 
1354 static void garmin_throttle(struct tty_struct *tty)
1355 {
1356  struct usb_serial_port *port = tty->driver_data;
1357  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1358 
1359  /* set flag, data received will be put into a queue
1360  for later processing */
1361  spin_lock_irq(&garmin_data_p->lock);
1362  garmin_data_p->flags |= FLAGS_QUEUING|FLAGS_THROTTLED;
1363  spin_unlock_irq(&garmin_data_p->lock);
1364 }
1365 
1366 
1367 static void garmin_unthrottle(struct tty_struct *tty)
1368 {
1369  struct usb_serial_port *port = tty->driver_data;
1370  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1371  int status;
1372 
1373  spin_lock_irq(&garmin_data_p->lock);
1374  garmin_data_p->flags &= ~FLAGS_THROTTLED;
1375  spin_unlock_irq(&garmin_data_p->lock);
1376 
1377  /* in native mode send queued data to tty, in
1378  serial mode nothing needs to be done here */
1379  if (garmin_data_p->mode == MODE_NATIVE)
1380  garmin_flush_queue(garmin_data_p);
1381 
1382  if (0 != (garmin_data_p->flags & FLAGS_BULK_IN_ACTIVE)) {
1383  status = usb_submit_urb(port->read_urb, GFP_KERNEL);
1384  if (status)
1385  dev_err(&port->dev,
1386  "%s - failed resubmitting read urb, error %d\n",
1387  __func__, status);
1388  }
1389 }
1390 
1391 /*
1392  * The timer is currently only used to send queued packets to
1393  * the tty in cases where the protocol provides no own handshaking
1394  * to initiate the transfer.
1395  */
1396 static void timeout_handler(unsigned long data)
1397 {
1398  struct garmin_data *garmin_data_p = (struct garmin_data *) data;
1399 
1400  /* send the next queued packet to the tty port */
1401  if (garmin_data_p->mode == MODE_NATIVE)
1402  if (garmin_data_p->flags & FLAGS_QUEUING)
1403  garmin_flush_queue(garmin_data_p);
1404 }
1405 
1406 
1407 
1408 static int garmin_port_probe(struct usb_serial_port *port)
1409 {
1410  int status;
1411  struct garmin_data *garmin_data_p;
1412 
1413  garmin_data_p = kzalloc(sizeof(struct garmin_data), GFP_KERNEL);
1414  if (garmin_data_p == NULL) {
1415  dev_err(&port->dev, "%s - Out of memory\n", __func__);
1416  return -ENOMEM;
1417  }
1418  init_timer(&garmin_data_p->timer);
1419  spin_lock_init(&garmin_data_p->lock);
1420  INIT_LIST_HEAD(&garmin_data_p->pktlist);
1421  /* garmin_data_p->timer.expires = jiffies + session_timeout; */
1422  garmin_data_p->timer.data = (unsigned long)garmin_data_p;
1423  garmin_data_p->timer.function = timeout_handler;
1424  garmin_data_p->port = port;
1425  garmin_data_p->state = 0;
1426  garmin_data_p->flags = 0;
1427  garmin_data_p->count = 0;
1428  usb_set_serial_port_data(port, garmin_data_p);
1429 
1430  status = garmin_init_session(port);
1431 
1432  return status;
1433 }
1434 
1435 
1436 static int garmin_port_remove(struct usb_serial_port *port)
1437 {
1438  struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1439 
1440  usb_kill_urb(port->interrupt_in_urb);
1441  del_timer_sync(&garmin_data_p->timer);
1442  kfree(garmin_data_p);
1443  return 0;
1444 }
1445 
1446 
1447 /* All of the device info needed */
1448 static struct usb_serial_driver garmin_device = {
1449  .driver = {
1450  .owner = THIS_MODULE,
1451  .name = "garmin_gps",
1452  },
1453  .description = "Garmin GPS usb/tty",
1454  .id_table = id_table,
1455  .num_ports = 1,
1456  .open = garmin_open,
1457  .close = garmin_close,
1458  .throttle = garmin_throttle,
1459  .unthrottle = garmin_unthrottle,
1460  .port_probe = garmin_port_probe,
1461  .port_remove = garmin_port_remove,
1462  .write = garmin_write,
1463  .write_room = garmin_write_room,
1464  .write_bulk_callback = garmin_write_bulk_callback,
1465  .read_bulk_callback = garmin_read_bulk_callback,
1466  .read_int_callback = garmin_read_int_callback,
1467 };
1468 
1469 static struct usb_serial_driver * const serial_drivers[] = {
1470  &garmin_device, NULL
1471 };
1472 
1473 module_usb_serial_driver(serial_drivers, id_table);
1474 
1475 MODULE_AUTHOR(DRIVER_AUTHOR);
1476 MODULE_DESCRIPTION(DRIVER_DESC);
1477 MODULE_LICENSE("GPL");
1478 
1479 module_param(initial_mode, int, S_IRUGO);
1480 MODULE_PARM_DESC(initial_mode, "Initial mode");
Generated on Thu Jan 10 2013 14:38:14 for Linux Kernel by   doxygen 1.8.2