1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Garmin GPS driver
4 *
5 * Copyright (C) 2006-2011 Hermann Kneissel herkne@gmx.de
6 *
7 * The latest version of the driver can be found at
8 * http://sourceforge.net/projects/garmin-gps/
9 *
10 * This driver has been derived from v2.1 of the visor driver.
11 */
12
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/slab.h>
16 #include <linux/timer.h>
17 #include <linux/tty.h>
18 #include <linux/tty_driver.h>
19 #include <linux/tty_flip.h>
20 #include <linux/module.h>
21 #include <linux/spinlock.h>
22 #include <linux/uaccess.h>
23 #include <linux/atomic.h>
24 #include <linux/usb.h>
25 #include <linux/usb/serial.h>
26
27 /* the mode to be set when the port ist opened */
28 static int initial_mode = 1;
29
30 #define GARMIN_VENDOR_ID 0x091E
31
32 /*
33 * Version Information
34 */
35
36 #define VERSION_MAJOR 0
37 #define VERSION_MINOR 36
38
39 #define _STR(s) #s
40 #define _DRIVER_VERSION(a, b) "v" _STR(a) "." _STR(b)
41 #define DRIVER_VERSION _DRIVER_VERSION(VERSION_MAJOR, VERSION_MINOR)
42 #define DRIVER_AUTHOR "hermann kneissel"
43 #define DRIVER_DESC "garmin gps driver"
44
45 /* error codes returned by the driver */
46 #define EINVPKT 1000 /* invalid packet structure */
47
48
49 /* size of the header of a packet using the usb protocol */
50 #define GARMIN_PKTHDR_LENGTH 12
51
52 /* max. possible size of a packet using the serial protocol */
53 #define MAX_SERIAL_PKT_SIZ (3 + 255 + 3)
54
55 /* max. possible size of a packet with worst case stuffing */
56 #define MAX_SERIAL_PKT_SIZ_STUFFED (MAX_SERIAL_PKT_SIZ + 256)
57
58 /* size of a buffer able to hold a complete (no stuffing) packet
59 * (the document protocol does not contain packets with a larger
60 * size, but in theory a packet may be 64k+12 bytes - if in
61 * later protocol versions larger packet sizes occur, this value
62 * should be increased accordingly, so the input buffer is always
63 * large enough the store a complete packet inclusive header) */
64 #define GPS_IN_BUFSIZ (GARMIN_PKTHDR_LENGTH+MAX_SERIAL_PKT_SIZ)
65
66 /* size of a buffer able to hold a complete (incl. stuffing) packet */
67 #define GPS_OUT_BUFSIZ (GARMIN_PKTHDR_LENGTH+MAX_SERIAL_PKT_SIZ_STUFFED)
68
69 /* where to place the packet id of a serial packet, so we can
70 * prepend the usb-packet header without the need to move the
71 * packets data */
72 #define GSP_INITIAL_OFFSET (GARMIN_PKTHDR_LENGTH-2)
73
74 /* max. size of incoming private packets (header+1 param) */
75 #define PRIVPKTSIZ (GARMIN_PKTHDR_LENGTH+4)
76
77 #define GARMIN_LAYERID_TRANSPORT 0
78 #define GARMIN_LAYERID_APPL 20
79 /* our own layer-id to use for some control mechanisms */
80 #define GARMIN_LAYERID_PRIVATE 0x01106E4B
81
82 #define GARMIN_PKTID_PVT_DATA 51
83 #define GARMIN_PKTID_L001_COMMAND_DATA 10
84
85 #define CMND_ABORT_TRANSFER 0
86
87 /* packet ids used in private layer */
88 #define PRIV_PKTID_SET_DEBUG 1
89 #define PRIV_PKTID_SET_MODE 2
90 #define PRIV_PKTID_INFO_REQ 3
91 #define PRIV_PKTID_INFO_RESP 4
92 #define PRIV_PKTID_RESET_REQ 5
93 #define PRIV_PKTID_SET_DEF_MODE 6
94
95
96 #define ETX 0x03
97 #define DLE 0x10
98 #define ACK 0x06
99 #define NAK 0x15
100
101 /* structure used to queue incoming packets */
102 struct garmin_packet {
103 struct list_head list;
104 int seq;
105 /* the real size of the data array, always > 0 */
106 int size;
107 __u8 data[];
108 };
109
110 /* structure used to keep the current state of the driver */
111 struct garmin_data {
112 __u8 state;
113 __u16 flags;
114 __u8 mode;
115 __u8 count;
116 __u8 pkt_id;
117 __u32 serial_num;
118 struct timer_list timer;
119 struct usb_serial_port *port;
120 int seq_counter;
121 int insize;
122 int outsize;
123 __u8 inbuffer [GPS_IN_BUFSIZ]; /* tty -> usb */
124 __u8 outbuffer[GPS_OUT_BUFSIZ]; /* usb -> tty */
125 __u8 privpkt[4*6];
126 spinlock_t lock;
127 struct list_head pktlist;
128 struct usb_anchor write_urbs;
129 };
130
131
132 #define STATE_NEW 0
133 #define STATE_INITIAL_DELAY 1
134 #define STATE_TIMEOUT 2
135 #define STATE_SESSION_REQ1 3
136 #define STATE_SESSION_REQ2 4
137 #define STATE_ACTIVE 5
138
139 #define STATE_RESET 8
140 #define STATE_DISCONNECTED 9
141 #define STATE_WAIT_TTY_ACK 10
142 #define STATE_GSP_WAIT_DATA 11
143
144 #define MODE_NATIVE 0
145 #define MODE_GARMIN_SERIAL 1
146
147 /* Flags used in garmin_data.flags: */
148 #define FLAGS_SESSION_REPLY_MASK 0x00C0
149 #define FLAGS_SESSION_REPLY1_SEEN 0x0080
150 #define FLAGS_SESSION_REPLY2_SEEN 0x0040
151 #define FLAGS_BULK_IN_ACTIVE 0x0020
152 #define FLAGS_BULK_IN_RESTART 0x0010
153 #define FLAGS_THROTTLED 0x0008
154 #define APP_REQ_SEEN 0x0004
155 #define APP_RESP_SEEN 0x0002
156 #define CLEAR_HALT_REQUIRED 0x0001
157
158 #define FLAGS_QUEUING 0x0100
159 #define FLAGS_DROP_DATA 0x0800
160
161 #define FLAGS_GSP_SKIP 0x1000
162 #define FLAGS_GSP_DLESEEN 0x2000
163
164
165
166
167
168
169 /* function prototypes */
170 static int gsp_next_packet(struct garmin_data *garmin_data_p);
171 static int garmin_write_bulk(struct usb_serial_port *port,
172 const unsigned char *buf, int count,
173 int dismiss_ack);
174
175 /* some special packets to be send or received */
176 static unsigned char const GARMIN_START_SESSION_REQ[]
177 = { 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0 };
178 static unsigned char const GARMIN_START_SESSION_REPLY[]
179 = { 0, 0, 0, 0, 6, 0, 0, 0, 4, 0, 0, 0 };
180 static unsigned char const GARMIN_BULK_IN_AVAIL_REPLY[]
181 = { 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0 };
182 static unsigned char const GARMIN_STOP_TRANSFER_REQ[]
183 = { 20, 0, 0, 0, 10, 0, 0, 0, 2, 0, 0, 0, 0, 0 };
184 static unsigned char const GARMIN_STOP_TRANSFER_REQ_V2[]
185 = { 20, 0, 0, 0, 10, 0, 0, 0, 1, 0, 0, 0, 0 };
186
187 /* packets currently unused, left as documentation */
188 #if 0
189 static unsigned char const GARMIN_APP_LAYER_REPLY[]
190 = { 0x14, 0, 0, 0 };
191 static unsigned char const GARMIN_START_PVT_REQ[]
192 = { 20, 0, 0, 0, 10, 0, 0, 0, 2, 0, 0, 0, 49, 0 };
193 static unsigned char const GARMIN_STOP_PVT_REQ[]
194 = { 20, 0, 0, 0, 10, 0, 0, 0, 2, 0, 0, 0, 50, 0 };
195 static unsigned char const PRIVATE_REQ[]
196 = { 0x4B, 0x6E, 0x10, 0x01, 0xFF, 0, 0, 0, 0xFF, 0, 0, 0 };
197 #endif
198
199
200 static const struct usb_device_id id_table[] = {
201 /* the same device id seems to be used by all
202 usb enabled GPS devices */
203 { USB_DEVICE(GARMIN_VENDOR_ID, 3) },
204 { } /* Terminating entry */
205 };
206 MODULE_DEVICE_TABLE(usb, id_table);
207
208
getLayerId(const __u8 * usbPacket)209 static inline int getLayerId(const __u8 *usbPacket)
210 {
211 return __le32_to_cpup((__le32 *)(usbPacket));
212 }
213
getPacketId(const __u8 * usbPacket)214 static inline int getPacketId(const __u8 *usbPacket)
215 {
216 return __le32_to_cpup((__le32 *)(usbPacket+4));
217 }
218
getDataLength(const __u8 * usbPacket)219 static inline int getDataLength(const __u8 *usbPacket)
220 {
221 return __le32_to_cpup((__le32 *)(usbPacket+8));
222 }
223
224
225 /*
226 * check if the usb-packet in buf contains an abort-transfer command.
227 * (if yes, all queued data will be dropped)
228 */
isAbortTrfCmnd(const unsigned char * buf)229 static inline int isAbortTrfCmnd(const unsigned char *buf)
230 {
231 if (memcmp(buf, GARMIN_STOP_TRANSFER_REQ,
232 sizeof(GARMIN_STOP_TRANSFER_REQ)) == 0 ||
233 memcmp(buf, GARMIN_STOP_TRANSFER_REQ_V2,
234 sizeof(GARMIN_STOP_TRANSFER_REQ_V2)) == 0)
235 return 1;
236 else
237 return 0;
238 }
239
240
241
send_to_tty(struct usb_serial_port * port,char * data,unsigned int actual_length)242 static void send_to_tty(struct usb_serial_port *port,
243 char *data, unsigned int actual_length)
244 {
245 if (actual_length) {
246 usb_serial_debug_data(&port->dev, __func__, actual_length, data);
247 tty_insert_flip_string(&port->port, data, actual_length);
248 tty_flip_buffer_push(&port->port);
249 }
250 }
251
252
253 /******************************************************************************
254 * packet queue handling
255 ******************************************************************************/
256
257 /*
258 * queue a received (usb-)packet for later processing
259 */
pkt_add(struct garmin_data * garmin_data_p,unsigned char * data,unsigned int data_length)260 static int pkt_add(struct garmin_data *garmin_data_p,
261 unsigned char *data, unsigned int data_length)
262 {
263 int state = 0;
264 int result = 0;
265 unsigned long flags;
266 struct garmin_packet *pkt;
267
268 /* process only packets containing data ... */
269 if (data_length) {
270 pkt = kmalloc(sizeof(struct garmin_packet)+data_length,
271 GFP_ATOMIC);
272 if (!pkt)
273 return 0;
274
275 pkt->size = data_length;
276 memcpy(pkt->data, data, data_length);
277
278 spin_lock_irqsave(&garmin_data_p->lock, flags);
279 garmin_data_p->flags |= FLAGS_QUEUING;
280 result = list_empty(&garmin_data_p->pktlist);
281 pkt->seq = garmin_data_p->seq_counter++;
282 list_add_tail(&pkt->list, &garmin_data_p->pktlist);
283 state = garmin_data_p->state;
284 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
285
286 dev_dbg(&garmin_data_p->port->dev,
287 "%s - added: pkt: %d - %d bytes\n", __func__,
288 pkt->seq, data_length);
289
290 /* in serial mode, if someone is waiting for data from
291 the device, convert and send the next packet to tty. */
292 if (result && (state == STATE_GSP_WAIT_DATA))
293 gsp_next_packet(garmin_data_p);
294 }
295 return result;
296 }
297
298
299 /* get the next pending packet */
pkt_pop(struct garmin_data * garmin_data_p)300 static struct garmin_packet *pkt_pop(struct garmin_data *garmin_data_p)
301 {
302 unsigned long flags;
303 struct garmin_packet *result = NULL;
304
305 spin_lock_irqsave(&garmin_data_p->lock, flags);
306 if (!list_empty(&garmin_data_p->pktlist)) {
307 result = (struct garmin_packet *)garmin_data_p->pktlist.next;
308 list_del(&result->list);
309 }
310 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
311 return result;
312 }
313
314
315 /* free up all queued data */
pkt_clear(struct garmin_data * garmin_data_p)316 static void pkt_clear(struct garmin_data *garmin_data_p)
317 {
318 unsigned long flags;
319 struct garmin_packet *result = NULL;
320
321 spin_lock_irqsave(&garmin_data_p->lock, flags);
322 while (!list_empty(&garmin_data_p->pktlist)) {
323 result = (struct garmin_packet *)garmin_data_p->pktlist.next;
324 list_del(&result->list);
325 kfree(result);
326 }
327 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
328 }
329
330
331 /******************************************************************************
332 * garmin serial protocol handling handling
333 ******************************************************************************/
334
335 /* send an ack packet back to the tty */
gsp_send_ack(struct garmin_data * garmin_data_p,__u8 pkt_id)336 static int gsp_send_ack(struct garmin_data *garmin_data_p, __u8 pkt_id)
337 {
338 __u8 pkt[10];
339 __u8 cksum = 0;
340 __u8 *ptr = pkt;
341 unsigned l = 0;
342
343 dev_dbg(&garmin_data_p->port->dev, "%s - pkt-id: 0x%X.\n", __func__,
344 pkt_id);
345
346 *ptr++ = DLE;
347 *ptr++ = ACK;
348 cksum += ACK;
349
350 *ptr++ = 2;
351 cksum += 2;
352
353 *ptr++ = pkt_id;
354 cksum += pkt_id;
355
356 if (pkt_id == DLE)
357 *ptr++ = DLE;
358
359 *ptr++ = 0;
360 *ptr++ = (-cksum) & 0xFF;
361 *ptr++ = DLE;
362 *ptr++ = ETX;
363
364 l = ptr-pkt;
365
366 send_to_tty(garmin_data_p->port, pkt, l);
367 return 0;
368 }
369
370
371
372 /*
373 * called for a complete packet received from tty layer
374 *
375 * the complete packet (pktid ... cksum) is in garmin_data_p->inbuf starting
376 * at GSP_INITIAL_OFFSET.
377 *
378 * count - number of bytes in the input buffer including space reserved for
379 * the usb header: GSP_INITIAL_OFFSET + number of bytes in packet
380 * (including pkt-id, data-length a. cksum)
381 */
gsp_rec_packet(struct garmin_data * garmin_data_p,int count)382 static int gsp_rec_packet(struct garmin_data *garmin_data_p, int count)
383 {
384 struct device *dev = &garmin_data_p->port->dev;
385 unsigned long flags;
386 const __u8 *recpkt = garmin_data_p->inbuffer+GSP_INITIAL_OFFSET;
387 __le32 *usbdata = (__le32 *) garmin_data_p->inbuffer;
388 int cksum = 0;
389 int n = 0;
390 int pktid = recpkt[0];
391 int size = recpkt[1];
392
393 usb_serial_debug_data(&garmin_data_p->port->dev, __func__,
394 count-GSP_INITIAL_OFFSET, recpkt);
395
396 if (size != (count-GSP_INITIAL_OFFSET-3)) {
397 dev_dbg(dev, "%s - invalid size, expected %d bytes, got %d\n",
398 __func__, size, (count-GSP_INITIAL_OFFSET-3));
399 return -EINVPKT;
400 }
401
402 cksum += *recpkt++;
403 cksum += *recpkt++;
404
405 /* sanity check, remove after test ... */
406 if ((__u8 *)&(usbdata[3]) != recpkt) {
407 dev_dbg(dev, "%s - ptr mismatch %p - %p\n", __func__,
408 &(usbdata[4]), recpkt);
409 return -EINVPKT;
410 }
411
412 while (n < size) {
413 cksum += *recpkt++;
414 n++;
415 }
416
417 if (((cksum + *recpkt) & 0xff) != 0) {
418 dev_dbg(dev, "%s - invalid checksum, expected %02x, got %02x\n",
419 __func__, -cksum & 0xff, *recpkt);
420 return -EINVPKT;
421 }
422
423 usbdata[0] = __cpu_to_le32(GARMIN_LAYERID_APPL);
424 usbdata[1] = __cpu_to_le32(pktid);
425 usbdata[2] = __cpu_to_le32(size);
426
427 garmin_write_bulk(garmin_data_p->port, garmin_data_p->inbuffer,
428 GARMIN_PKTHDR_LENGTH+size, 0);
429
430 /* if this was an abort-transfer command, flush all
431 queued data. */
432 if (isAbortTrfCmnd(garmin_data_p->inbuffer)) {
433 spin_lock_irqsave(&garmin_data_p->lock, flags);
434 garmin_data_p->flags |= FLAGS_DROP_DATA;
435 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
436 pkt_clear(garmin_data_p);
437 }
438
439 return count;
440 }
441
442
443
444 /*
445 * Called for data received from tty
446 *
447 * buf contains the data read, it may span more than one packet or even
448 * incomplete packets
449 *
450 * input record should be a serial-record, but it may not be complete.
451 * Copy it into our local buffer, until an etx is seen (or an error
452 * occurs).
453 * Once the record is complete, convert into a usb packet and send it
454 * to the bulk pipe, send an ack back to the tty.
455 *
456 * If the input is an ack, just send the last queued packet to the
457 * tty layer.
458 *
459 * if the input is an abort command, drop all queued data.
460 */
461
gsp_receive(struct garmin_data * garmin_data_p,const unsigned char * buf,int count)462 static int gsp_receive(struct garmin_data *garmin_data_p,
463 const unsigned char *buf, int count)
464 {
465 struct device *dev = &garmin_data_p->port->dev;
466 unsigned long flags;
467 int offs = 0;
468 int ack_or_nak_seen = 0;
469 __u8 *dest;
470 int size;
471 /* dleSeen: set if last byte read was a DLE */
472 int dleSeen;
473 /* skip: if set, skip incoming data until possible start of
474 * new packet
475 */
476 int skip;
477 __u8 data;
478
479 spin_lock_irqsave(&garmin_data_p->lock, flags);
480 dest = garmin_data_p->inbuffer;
481 size = garmin_data_p->insize;
482 dleSeen = garmin_data_p->flags & FLAGS_GSP_DLESEEN;
483 skip = garmin_data_p->flags & FLAGS_GSP_SKIP;
484 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
485
486 /* dev_dbg(dev, "%s - dle=%d skip=%d size=%d count=%d\n",
487 __func__, dleSeen, skip, size, count); */
488
489 if (size == 0)
490 size = GSP_INITIAL_OFFSET;
491
492 while (offs < count) {
493
494 data = *(buf+offs);
495 offs++;
496
497 if (data == DLE) {
498 if (skip) { /* start of a new pkt */
499 skip = 0;
500 size = GSP_INITIAL_OFFSET;
501 dleSeen = 1;
502 } else if (dleSeen) {
503 dest[size++] = data;
504 dleSeen = 0;
505 } else {
506 dleSeen = 1;
507 }
508 } else if (data == ETX) {
509 if (dleSeen) {
510 /* packet complete */
511
512 data = dest[GSP_INITIAL_OFFSET];
513
514 if (data == ACK) {
515 ack_or_nak_seen = ACK;
516 dev_dbg(dev, "ACK packet complete.\n");
517 } else if (data == NAK) {
518 ack_or_nak_seen = NAK;
519 dev_dbg(dev, "NAK packet complete.\n");
520 } else {
521 dev_dbg(dev, "packet complete - id=0x%X.\n",
522 data);
523 gsp_rec_packet(garmin_data_p, size);
524 }
525
526 skip = 1;
527 size = GSP_INITIAL_OFFSET;
528 dleSeen = 0;
529 } else {
530 dest[size++] = data;
531 }
532 } else if (!skip) {
533
534 if (dleSeen) {
535 size = GSP_INITIAL_OFFSET;
536 dleSeen = 0;
537 }
538
539 dest[size++] = data;
540 }
541
542 if (size >= GPS_IN_BUFSIZ) {
543 dev_dbg(dev, "%s - packet too large.\n", __func__);
544 skip = 1;
545 size = GSP_INITIAL_OFFSET;
546 dleSeen = 0;
547 }
548 }
549
550 spin_lock_irqsave(&garmin_data_p->lock, flags);
551
552 garmin_data_p->insize = size;
553
554 /* copy flags back to structure */
555 if (skip)
556 garmin_data_p->flags |= FLAGS_GSP_SKIP;
557 else
558 garmin_data_p->flags &= ~FLAGS_GSP_SKIP;
559
560 if (dleSeen)
561 garmin_data_p->flags |= FLAGS_GSP_DLESEEN;
562 else
563 garmin_data_p->flags &= ~FLAGS_GSP_DLESEEN;
564
565 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
566
567 if (ack_or_nak_seen) {
568 if (gsp_next_packet(garmin_data_p) > 0)
569 garmin_data_p->state = STATE_ACTIVE;
570 else
571 garmin_data_p->state = STATE_GSP_WAIT_DATA;
572 }
573 return count;
574 }
575
576
577
578 /*
579 * Sends a usb packet to the tty
580 *
581 * Assumes, that all packages and at an usb-packet boundary.
582 *
583 * return <0 on error, 0 if packet is incomplete or > 0 if packet was sent
584 */
gsp_send(struct garmin_data * garmin_data_p,const unsigned char * buf,int count)585 static int gsp_send(struct garmin_data *garmin_data_p,
586 const unsigned char *buf, int count)
587 {
588 struct device *dev = &garmin_data_p->port->dev;
589 const unsigned char *src;
590 unsigned char *dst;
591 int pktid = 0;
592 int datalen = 0;
593 int cksum = 0;
594 int i = 0;
595 int k;
596
597 dev_dbg(dev, "%s - state %d - %d bytes.\n", __func__,
598 garmin_data_p->state, count);
599
600 k = garmin_data_p->outsize;
601 if ((k+count) > GPS_OUT_BUFSIZ) {
602 dev_dbg(dev, "packet too large\n");
603 garmin_data_p->outsize = 0;
604 return -4;
605 }
606
607 memcpy(garmin_data_p->outbuffer+k, buf, count);
608 k += count;
609 garmin_data_p->outsize = k;
610
611 if (k >= GARMIN_PKTHDR_LENGTH) {
612 pktid = getPacketId(garmin_data_p->outbuffer);
613 datalen = getDataLength(garmin_data_p->outbuffer);
614 i = GARMIN_PKTHDR_LENGTH + datalen;
615 if (k < i)
616 return 0;
617 } else {
618 return 0;
619 }
620
621 dev_dbg(dev, "%s - %d bytes in buffer, %d bytes in pkt.\n", __func__, k, i);
622
623 /* garmin_data_p->outbuffer now contains a complete packet */
624
625 usb_serial_debug_data(&garmin_data_p->port->dev, __func__, k,
626 garmin_data_p->outbuffer);
627
628 garmin_data_p->outsize = 0;
629
630 if (getLayerId(garmin_data_p->outbuffer) != GARMIN_LAYERID_APPL) {
631 dev_dbg(dev, "not an application packet (%d)\n",
632 getLayerId(garmin_data_p->outbuffer));
633 return -1;
634 }
635
636 if (pktid > 255) {
637 dev_dbg(dev, "packet-id %d too large\n", pktid);
638 return -2;
639 }
640
641 if (datalen > 255) {
642 dev_dbg(dev, "packet-size %d too large\n", datalen);
643 return -3;
644 }
645
646 /* the serial protocol should be able to handle this packet */
647
648 k = 0;
649 src = garmin_data_p->outbuffer+GARMIN_PKTHDR_LENGTH;
650 for (i = 0; i < datalen; i++) {
651 if (*src++ == DLE)
652 k++;
653 }
654
655 src = garmin_data_p->outbuffer+GARMIN_PKTHDR_LENGTH;
656 if (k > (GARMIN_PKTHDR_LENGTH-2)) {
657 /* can't add stuffing DLEs in place, move data to end
658 of buffer ... */
659 dst = garmin_data_p->outbuffer+GPS_OUT_BUFSIZ-datalen;
660 memcpy(dst, src, datalen);
661 src = dst;
662 }
663
664 dst = garmin_data_p->outbuffer;
665
666 *dst++ = DLE;
667 *dst++ = pktid;
668 cksum += pktid;
669 *dst++ = datalen;
670 cksum += datalen;
671 if (datalen == DLE)
672 *dst++ = DLE;
673
674 for (i = 0; i < datalen; i++) {
675 __u8 c = *src++;
676 *dst++ = c;
677 cksum += c;
678 if (c == DLE)
679 *dst++ = DLE;
680 }
681
682 cksum = -cksum & 0xFF;
683 *dst++ = cksum;
684 if (cksum == DLE)
685 *dst++ = DLE;
686 *dst++ = DLE;
687 *dst++ = ETX;
688
689 i = dst-garmin_data_p->outbuffer;
690
691 send_to_tty(garmin_data_p->port, garmin_data_p->outbuffer, i);
692
693 garmin_data_p->pkt_id = pktid;
694 garmin_data_p->state = STATE_WAIT_TTY_ACK;
695
696 return i;
697 }
698
699
700 /*
701 * Process the next pending data packet - if there is one
702 */
gsp_next_packet(struct garmin_data * garmin_data_p)703 static int gsp_next_packet(struct garmin_data *garmin_data_p)
704 {
705 int result = 0;
706 struct garmin_packet *pkt = NULL;
707
708 while ((pkt = pkt_pop(garmin_data_p)) != NULL) {
709 dev_dbg(&garmin_data_p->port->dev, "%s - next pkt: %d\n", __func__, pkt->seq);
710 result = gsp_send(garmin_data_p, pkt->data, pkt->size);
711 if (result > 0) {
712 kfree(pkt);
713 return result;
714 }
715 kfree(pkt);
716 }
717 return result;
718 }
719
720
721
722 /******************************************************************************
723 * garmin native mode
724 ******************************************************************************/
725
726
727 /*
728 * Called for data received from tty
729 *
730 * The input data is expected to be in garmin usb-packet format.
731 *
732 * buf contains the data read, it may span more than one packet
733 * or even incomplete packets
734 */
nat_receive(struct garmin_data * garmin_data_p,const unsigned char * buf,int count)735 static int nat_receive(struct garmin_data *garmin_data_p,
736 const unsigned char *buf, int count)
737 {
738 unsigned long flags;
739 __u8 *dest;
740 int offs = 0;
741 int result = count;
742 int len;
743
744 while (offs < count) {
745 /* if buffer contains header, copy rest of data */
746 if (garmin_data_p->insize >= GARMIN_PKTHDR_LENGTH)
747 len = GARMIN_PKTHDR_LENGTH
748 +getDataLength(garmin_data_p->inbuffer);
749 else
750 len = GARMIN_PKTHDR_LENGTH;
751
752 if (len >= GPS_IN_BUFSIZ) {
753 /* seems to be an invalid packet, ignore rest
754 of input */
755 dev_dbg(&garmin_data_p->port->dev,
756 "%s - packet size too large: %d\n",
757 __func__, len);
758 garmin_data_p->insize = 0;
759 count = 0;
760 result = -EINVPKT;
761 } else {
762 len -= garmin_data_p->insize;
763 if (len > (count-offs))
764 len = (count-offs);
765 if (len > 0) {
766 dest = garmin_data_p->inbuffer
767 + garmin_data_p->insize;
768 memcpy(dest, buf+offs, len);
769 garmin_data_p->insize += len;
770 offs += len;
771 }
772 }
773
774 /* do we have a complete packet ? */
775 if (garmin_data_p->insize >= GARMIN_PKTHDR_LENGTH) {
776 len = GARMIN_PKTHDR_LENGTH+
777 getDataLength(garmin_data_p->inbuffer);
778 if (garmin_data_p->insize >= len) {
779 garmin_write_bulk(garmin_data_p->port,
780 garmin_data_p->inbuffer,
781 len, 0);
782 garmin_data_p->insize = 0;
783
784 /* if this was an abort-transfer command,
785 flush all queued data. */
786 if (isAbortTrfCmnd(garmin_data_p->inbuffer)) {
787 spin_lock_irqsave(&garmin_data_p->lock,
788 flags);
789 garmin_data_p->flags |= FLAGS_DROP_DATA;
790 spin_unlock_irqrestore(
791 &garmin_data_p->lock, flags);
792 pkt_clear(garmin_data_p);
793 }
794 }
795 }
796 }
797 return result;
798 }
799
800
801 /******************************************************************************
802 * private packets
803 ******************************************************************************/
804
priv_status_resp(struct usb_serial_port * port)805 static void priv_status_resp(struct usb_serial_port *port)
806 {
807 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
808 __le32 *pkt = (__le32 *)garmin_data_p->privpkt;
809
810 pkt[0] = __cpu_to_le32(GARMIN_LAYERID_PRIVATE);
811 pkt[1] = __cpu_to_le32(PRIV_PKTID_INFO_RESP);
812 pkt[2] = __cpu_to_le32(12);
813 pkt[3] = __cpu_to_le32(VERSION_MAJOR << 16 | VERSION_MINOR);
814 pkt[4] = __cpu_to_le32(garmin_data_p->mode);
815 pkt[5] = __cpu_to_le32(garmin_data_p->serial_num);
816
817 send_to_tty(port, (__u8 *)pkt, 6 * 4);
818 }
819
820
821 /******************************************************************************
822 * Garmin specific driver functions
823 ******************************************************************************/
824
process_resetdev_request(struct usb_serial_port * port)825 static int process_resetdev_request(struct usb_serial_port *port)
826 {
827 unsigned long flags;
828 int status;
829 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
830
831 spin_lock_irqsave(&garmin_data_p->lock, flags);
832 garmin_data_p->flags &= ~(CLEAR_HALT_REQUIRED);
833 garmin_data_p->state = STATE_RESET;
834 garmin_data_p->serial_num = 0;
835 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
836
837 usb_kill_urb(port->interrupt_in_urb);
838 dev_dbg(&port->dev, "%s - usb_reset_device\n", __func__);
839 status = usb_reset_device(port->serial->dev);
840 if (status)
841 dev_dbg(&port->dev, "%s - usb_reset_device failed: %d\n",
842 __func__, status);
843 return status;
844 }
845
846
847
848 /*
849 * clear all cached data
850 */
garmin_clear(struct garmin_data * garmin_data_p)851 static int garmin_clear(struct garmin_data *garmin_data_p)
852 {
853 unsigned long flags;
854
855 /* flush all queued data */
856 pkt_clear(garmin_data_p);
857
858 spin_lock_irqsave(&garmin_data_p->lock, flags);
859 garmin_data_p->insize = 0;
860 garmin_data_p->outsize = 0;
861 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
862
863 return 0;
864 }
865
866
garmin_init_session(struct usb_serial_port * port)867 static int garmin_init_session(struct usb_serial_port *port)
868 {
869 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
870 int status;
871 int i;
872
873 usb_kill_urb(port->interrupt_in_urb);
874
875 status = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
876 if (status) {
877 dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
878 status);
879 return status;
880 }
881
882 /*
883 * using the initialization method from gpsbabel. See comments in
884 * gpsbabel/jeeps/gpslibusb.c gusb_reset_toggles()
885 */
886 dev_dbg(&port->dev, "%s - starting session ...\n", __func__);
887 garmin_data_p->state = STATE_ACTIVE;
888
889 for (i = 0; i < 3; i++) {
890 status = garmin_write_bulk(port, GARMIN_START_SESSION_REQ,
891 sizeof(GARMIN_START_SESSION_REQ), 0);
892 if (status < 0)
893 goto err_kill_urbs;
894 }
895
896 return 0;
897
898 err_kill_urbs:
899 usb_kill_anchored_urbs(&garmin_data_p->write_urbs);
900 usb_kill_urb(port->interrupt_in_urb);
901
902 return status;
903 }
904
905
906
garmin_open(struct tty_struct * tty,struct usb_serial_port * port)907 static int garmin_open(struct tty_struct *tty, struct usb_serial_port *port)
908 {
909 unsigned long flags;
910 int status = 0;
911 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
912
913 spin_lock_irqsave(&garmin_data_p->lock, flags);
914 garmin_data_p->mode = initial_mode;
915 garmin_data_p->count = 0;
916 garmin_data_p->flags &= FLAGS_SESSION_REPLY1_SEEN;
917 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
918
919 /* shutdown any bulk reads that might be going on */
920 usb_kill_urb(port->read_urb);
921
922 if (garmin_data_p->state == STATE_RESET)
923 status = garmin_init_session(port);
924
925 garmin_data_p->state = STATE_ACTIVE;
926 return status;
927 }
928
929
garmin_close(struct usb_serial_port * port)930 static void garmin_close(struct usb_serial_port *port)
931 {
932 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
933
934 dev_dbg(&port->dev, "%s - mode=%d state=%d flags=0x%X\n",
935 __func__, garmin_data_p->mode, garmin_data_p->state,
936 garmin_data_p->flags);
937
938 garmin_clear(garmin_data_p);
939
940 /* shutdown our urbs */
941 usb_kill_urb(port->read_urb);
942 usb_kill_anchored_urbs(&garmin_data_p->write_urbs);
943
944 /* keep reset state so we know that we must start a new session */
945 if (garmin_data_p->state != STATE_RESET)
946 garmin_data_p->state = STATE_DISCONNECTED;
947 }
948
949
garmin_write_bulk_callback(struct urb * urb)950 static void garmin_write_bulk_callback(struct urb *urb)
951 {
952 struct usb_serial_port *port = urb->context;
953
954 if (port) {
955 struct garmin_data *garmin_data_p =
956 usb_get_serial_port_data(port);
957
958 if (getLayerId(urb->transfer_buffer) == GARMIN_LAYERID_APPL) {
959
960 if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
961 gsp_send_ack(garmin_data_p,
962 ((__u8 *)urb->transfer_buffer)[4]);
963 }
964 }
965 usb_serial_port_softint(port);
966 }
967
968 /* Ignore errors that resulted from garmin_write_bulk with
969 dismiss_ack = 1 */
970
971 /* free up the transfer buffer, as usb_free_urb() does not do this */
972 kfree(urb->transfer_buffer);
973 }
974
975
garmin_write_bulk(struct usb_serial_port * port,const unsigned char * buf,int count,int dismiss_ack)976 static int garmin_write_bulk(struct usb_serial_port *port,
977 const unsigned char *buf, int count,
978 int dismiss_ack)
979 {
980 unsigned long flags;
981 struct usb_serial *serial = port->serial;
982 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
983 struct urb *urb;
984 unsigned char *buffer;
985 int status;
986
987 spin_lock_irqsave(&garmin_data_p->lock, flags);
988 garmin_data_p->flags &= ~FLAGS_DROP_DATA;
989 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
990
991 buffer = kmemdup(buf, count, GFP_ATOMIC);
992 if (!buffer)
993 return -ENOMEM;
994
995 urb = usb_alloc_urb(0, GFP_ATOMIC);
996 if (!urb) {
997 kfree(buffer);
998 return -ENOMEM;
999 }
1000
1001 usb_serial_debug_data(&port->dev, __func__, count, buffer);
1002
1003 usb_fill_bulk_urb(urb, serial->dev,
1004 usb_sndbulkpipe(serial->dev,
1005 port->bulk_out_endpointAddress),
1006 buffer, count,
1007 garmin_write_bulk_callback,
1008 dismiss_ack ? NULL : port);
1009 urb->transfer_flags |= URB_ZERO_PACKET;
1010
1011 if (getLayerId(buffer) == GARMIN_LAYERID_APPL) {
1012
1013 spin_lock_irqsave(&garmin_data_p->lock, flags);
1014 garmin_data_p->flags |= APP_REQ_SEEN;
1015 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1016
1017 if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
1018 pkt_clear(garmin_data_p);
1019 garmin_data_p->state = STATE_GSP_WAIT_DATA;
1020 }
1021 }
1022
1023 /* send it down the pipe */
1024 usb_anchor_urb(urb, &garmin_data_p->write_urbs);
1025 status = usb_submit_urb(urb, GFP_ATOMIC);
1026 if (status) {
1027 dev_err(&port->dev,
1028 "%s - usb_submit_urb(write bulk) failed with status = %d\n",
1029 __func__, status);
1030 count = status;
1031 usb_unanchor_urb(urb);
1032 kfree(buffer);
1033 }
1034
1035 /* we are done with this urb, so let the host driver
1036 * really free it when it is finished with it */
1037 usb_free_urb(urb);
1038
1039 return count;
1040 }
1041
garmin_write(struct tty_struct * tty,struct usb_serial_port * port,const unsigned char * buf,int count)1042 static int garmin_write(struct tty_struct *tty, struct usb_serial_port *port,
1043 const unsigned char *buf, int count)
1044 {
1045 struct device *dev = &port->dev;
1046 int pktid, pktsiz, len;
1047 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1048 __le32 *privpkt = (__le32 *)garmin_data_p->privpkt;
1049
1050 usb_serial_debug_data(dev, __func__, count, buf);
1051
1052 if (garmin_data_p->state == STATE_RESET)
1053 return -EIO;
1054
1055 /* check for our private packets */
1056 if (count >= GARMIN_PKTHDR_LENGTH) {
1057 len = PRIVPKTSIZ;
1058 if (count < len)
1059 len = count;
1060
1061 memcpy(garmin_data_p->privpkt, buf, len);
1062
1063 pktsiz = getDataLength(garmin_data_p->privpkt);
1064 pktid = getPacketId(garmin_data_p->privpkt);
1065
1066 if (count == (GARMIN_PKTHDR_LENGTH + pktsiz) &&
1067 getLayerId(garmin_data_p->privpkt) ==
1068 GARMIN_LAYERID_PRIVATE) {
1069
1070 dev_dbg(dev, "%s - processing private request %d\n",
1071 __func__, pktid);
1072
1073 /* drop all unfinished transfers */
1074 garmin_clear(garmin_data_p);
1075
1076 switch (pktid) {
1077 case PRIV_PKTID_SET_MODE:
1078 if (pktsiz != 4)
1079 return -EINVPKT;
1080 garmin_data_p->mode = __le32_to_cpu(privpkt[3]);
1081 dev_dbg(dev, "%s - mode set to %d\n",
1082 __func__, garmin_data_p->mode);
1083 break;
1084
1085 case PRIV_PKTID_INFO_REQ:
1086 priv_status_resp(port);
1087 break;
1088
1089 case PRIV_PKTID_RESET_REQ:
1090 process_resetdev_request(port);
1091 break;
1092
1093 case PRIV_PKTID_SET_DEF_MODE:
1094 if (pktsiz != 4)
1095 return -EINVPKT;
1096 initial_mode = __le32_to_cpu(privpkt[3]);
1097 dev_dbg(dev, "%s - initial_mode set to %d\n",
1098 __func__,
1099 garmin_data_p->mode);
1100 break;
1101 }
1102 return count;
1103 }
1104 }
1105
1106 if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
1107 return gsp_receive(garmin_data_p, buf, count);
1108 } else { /* MODE_NATIVE */
1109 return nat_receive(garmin_data_p, buf, count);
1110 }
1111 }
1112
1113
garmin_write_room(struct tty_struct * tty)1114 static unsigned int garmin_write_room(struct tty_struct *tty)
1115 {
1116 struct usb_serial_port *port = tty->driver_data;
1117 /*
1118 * Report back the bytes currently available in the output buffer.
1119 */
1120 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1121 return GPS_OUT_BUFSIZ-garmin_data_p->outsize;
1122 }
1123
1124
garmin_read_process(struct garmin_data * garmin_data_p,unsigned char * data,unsigned data_length,int bulk_data)1125 static void garmin_read_process(struct garmin_data *garmin_data_p,
1126 unsigned char *data, unsigned data_length,
1127 int bulk_data)
1128 {
1129 unsigned long flags;
1130
1131 if (garmin_data_p->flags & FLAGS_DROP_DATA) {
1132 /* abort-transfer cmd is active */
1133 dev_dbg(&garmin_data_p->port->dev, "%s - pkt dropped\n", __func__);
1134 } else if (garmin_data_p->state != STATE_DISCONNECTED &&
1135 garmin_data_p->state != STATE_RESET) {
1136
1137 /* if throttling is active or postprecessing is required
1138 put the received data in the input queue, otherwise
1139 send it directly to the tty port */
1140 if (garmin_data_p->flags & FLAGS_QUEUING) {
1141 pkt_add(garmin_data_p, data, data_length);
1142 } else if (bulk_data || (data_length >= sizeof(u32) &&
1143 getLayerId(data) == GARMIN_LAYERID_APPL)) {
1144
1145 spin_lock_irqsave(&garmin_data_p->lock, flags);
1146 garmin_data_p->flags |= APP_RESP_SEEN;
1147 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1148
1149 if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
1150 pkt_add(garmin_data_p, data, data_length);
1151 } else {
1152 send_to_tty(garmin_data_p->port, data,
1153 data_length);
1154 }
1155 }
1156 /* ignore system layer packets ... */
1157 }
1158 }
1159
1160
garmin_read_bulk_callback(struct urb * urb)1161 static void garmin_read_bulk_callback(struct urb *urb)
1162 {
1163 unsigned long flags;
1164 struct usb_serial_port *port = urb->context;
1165 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1166 unsigned char *data = urb->transfer_buffer;
1167 int status = urb->status;
1168 int retval;
1169
1170 if (status) {
1171 dev_dbg(&urb->dev->dev, "%s - nonzero read bulk status received: %d\n",
1172 __func__, status);
1173 return;
1174 }
1175
1176 usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
1177
1178 garmin_read_process(garmin_data_p, data, urb->actual_length, 1);
1179
1180 if (urb->actual_length == 0 &&
1181 (garmin_data_p->flags & FLAGS_BULK_IN_RESTART) != 0) {
1182 spin_lock_irqsave(&garmin_data_p->lock, flags);
1183 garmin_data_p->flags &= ~FLAGS_BULK_IN_RESTART;
1184 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1185 retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1186 if (retval)
1187 dev_err(&port->dev,
1188 "%s - failed resubmitting read urb, error %d\n",
1189 __func__, retval);
1190 } else if (urb->actual_length > 0) {
1191 /* Continue trying to read until nothing more is received */
1192 if ((garmin_data_p->flags & FLAGS_THROTTLED) == 0) {
1193 retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1194 if (retval)
1195 dev_err(&port->dev,
1196 "%s - failed resubmitting read urb, error %d\n",
1197 __func__, retval);
1198 }
1199 } else {
1200 dev_dbg(&port->dev, "%s - end of bulk data\n", __func__);
1201 spin_lock_irqsave(&garmin_data_p->lock, flags);
1202 garmin_data_p->flags &= ~FLAGS_BULK_IN_ACTIVE;
1203 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1204 }
1205 }
1206
1207
garmin_read_int_callback(struct urb * urb)1208 static void garmin_read_int_callback(struct urb *urb)
1209 {
1210 unsigned long flags;
1211 int retval;
1212 struct usb_serial_port *port = urb->context;
1213 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1214 unsigned char *data = urb->transfer_buffer;
1215 int status = urb->status;
1216
1217 switch (status) {
1218 case 0:
1219 /* success */
1220 break;
1221 case -ECONNRESET:
1222 case -ENOENT:
1223 case -ESHUTDOWN:
1224 /* this urb is terminated, clean up */
1225 dev_dbg(&urb->dev->dev, "%s - urb shutting down with status: %d\n",
1226 __func__, status);
1227 return;
1228 default:
1229 dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n",
1230 __func__, status);
1231 return;
1232 }
1233
1234 usb_serial_debug_data(&port->dev, __func__, urb->actual_length,
1235 urb->transfer_buffer);
1236
1237 if (urb->actual_length == sizeof(GARMIN_BULK_IN_AVAIL_REPLY) &&
1238 memcmp(data, GARMIN_BULK_IN_AVAIL_REPLY,
1239 sizeof(GARMIN_BULK_IN_AVAIL_REPLY)) == 0) {
1240
1241 dev_dbg(&port->dev, "%s - bulk data available.\n", __func__);
1242
1243 if ((garmin_data_p->flags & FLAGS_BULK_IN_ACTIVE) == 0) {
1244
1245 /* bulk data available */
1246 retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1247 if (retval) {
1248 dev_err(&port->dev,
1249 "%s - failed submitting read urb, error %d\n",
1250 __func__, retval);
1251 } else {
1252 spin_lock_irqsave(&garmin_data_p->lock, flags);
1253 garmin_data_p->flags |= FLAGS_BULK_IN_ACTIVE;
1254 spin_unlock_irqrestore(&garmin_data_p->lock,
1255 flags);
1256 }
1257 } else {
1258 /* bulk-in transfer still active */
1259 spin_lock_irqsave(&garmin_data_p->lock, flags);
1260 garmin_data_p->flags |= FLAGS_BULK_IN_RESTART;
1261 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1262 }
1263
1264 } else if (urb->actual_length == (4+sizeof(GARMIN_START_SESSION_REPLY))
1265 && memcmp(data, GARMIN_START_SESSION_REPLY,
1266 sizeof(GARMIN_START_SESSION_REPLY)) == 0) {
1267
1268 spin_lock_irqsave(&garmin_data_p->lock, flags);
1269 garmin_data_p->flags |= FLAGS_SESSION_REPLY1_SEEN;
1270 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1271
1272 /* save the serial number */
1273 garmin_data_p->serial_num = __le32_to_cpup(
1274 (__le32 *)(data+GARMIN_PKTHDR_LENGTH));
1275
1276 dev_dbg(&port->dev, "%s - start-of-session reply seen - serial %u.\n",
1277 __func__, garmin_data_p->serial_num);
1278 }
1279
1280 garmin_read_process(garmin_data_p, data, urb->actual_length, 0);
1281
1282 retval = usb_submit_urb(urb, GFP_ATOMIC);
1283 if (retval)
1284 dev_err(&urb->dev->dev,
1285 "%s - Error %d submitting interrupt urb\n",
1286 __func__, retval);
1287 }
1288
1289
1290 /*
1291 * Sends the next queued packt to the tty port (garmin native mode only)
1292 * and then sets a timer to call itself again until all queued data
1293 * is sent.
1294 */
garmin_flush_queue(struct garmin_data * garmin_data_p)1295 static int garmin_flush_queue(struct garmin_data *garmin_data_p)
1296 {
1297 unsigned long flags;
1298 struct garmin_packet *pkt;
1299
1300 if ((garmin_data_p->flags & FLAGS_THROTTLED) == 0) {
1301 pkt = pkt_pop(garmin_data_p);
1302 if (pkt != NULL) {
1303 send_to_tty(garmin_data_p->port, pkt->data, pkt->size);
1304 kfree(pkt);
1305 mod_timer(&garmin_data_p->timer, (1)+jiffies);
1306
1307 } else {
1308 spin_lock_irqsave(&garmin_data_p->lock, flags);
1309 garmin_data_p->flags &= ~FLAGS_QUEUING;
1310 spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1311 }
1312 }
1313 return 0;
1314 }
1315
1316
garmin_throttle(struct tty_struct * tty)1317 static void garmin_throttle(struct tty_struct *tty)
1318 {
1319 struct usb_serial_port *port = tty->driver_data;
1320 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1321
1322 /* set flag, data received will be put into a queue
1323 for later processing */
1324 spin_lock_irq(&garmin_data_p->lock);
1325 garmin_data_p->flags |= FLAGS_QUEUING|FLAGS_THROTTLED;
1326 spin_unlock_irq(&garmin_data_p->lock);
1327 }
1328
1329
garmin_unthrottle(struct tty_struct * tty)1330 static void garmin_unthrottle(struct tty_struct *tty)
1331 {
1332 struct usb_serial_port *port = tty->driver_data;
1333 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1334 int status;
1335
1336 spin_lock_irq(&garmin_data_p->lock);
1337 garmin_data_p->flags &= ~FLAGS_THROTTLED;
1338 spin_unlock_irq(&garmin_data_p->lock);
1339
1340 /* in native mode send queued data to tty, in
1341 serial mode nothing needs to be done here */
1342 if (garmin_data_p->mode == MODE_NATIVE)
1343 garmin_flush_queue(garmin_data_p);
1344
1345 if ((garmin_data_p->flags & FLAGS_BULK_IN_ACTIVE) != 0) {
1346 status = usb_submit_urb(port->read_urb, GFP_KERNEL);
1347 if (status)
1348 dev_err(&port->dev,
1349 "%s - failed resubmitting read urb, error %d\n",
1350 __func__, status);
1351 }
1352 }
1353
1354 /*
1355 * The timer is currently only used to send queued packets to
1356 * the tty in cases where the protocol provides no own handshaking
1357 * to initiate the transfer.
1358 */
timeout_handler(struct timer_list * t)1359 static void timeout_handler(struct timer_list *t)
1360 {
1361 struct garmin_data *garmin_data_p = from_timer(garmin_data_p, t, timer);
1362
1363 /* send the next queued packet to the tty port */
1364 if (garmin_data_p->mode == MODE_NATIVE)
1365 if (garmin_data_p->flags & FLAGS_QUEUING)
1366 garmin_flush_queue(garmin_data_p);
1367 }
1368
1369
1370
garmin_port_probe(struct usb_serial_port * port)1371 static int garmin_port_probe(struct usb_serial_port *port)
1372 {
1373 int status;
1374 struct garmin_data *garmin_data_p;
1375
1376 garmin_data_p = kzalloc(sizeof(struct garmin_data), GFP_KERNEL);
1377 if (!garmin_data_p)
1378 return -ENOMEM;
1379
1380 timer_setup(&garmin_data_p->timer, timeout_handler, 0);
1381 spin_lock_init(&garmin_data_p->lock);
1382 INIT_LIST_HEAD(&garmin_data_p->pktlist);
1383 garmin_data_p->port = port;
1384 garmin_data_p->state = 0;
1385 garmin_data_p->flags = 0;
1386 garmin_data_p->count = 0;
1387 init_usb_anchor(&garmin_data_p->write_urbs);
1388 usb_set_serial_port_data(port, garmin_data_p);
1389
1390 status = garmin_init_session(port);
1391 if (status)
1392 goto err_free;
1393
1394 return 0;
1395 err_free:
1396 kfree(garmin_data_p);
1397
1398 return status;
1399 }
1400
1401
garmin_port_remove(struct usb_serial_port * port)1402 static void garmin_port_remove(struct usb_serial_port *port)
1403 {
1404 struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1405
1406 usb_kill_anchored_urbs(&garmin_data_p->write_urbs);
1407 usb_kill_urb(port->interrupt_in_urb);
1408 del_timer_sync(&garmin_data_p->timer);
1409 kfree(garmin_data_p);
1410 }
1411
1412
1413 /* All of the device info needed */
1414 static struct usb_serial_driver garmin_device = {
1415 .driver = {
1416 .owner = THIS_MODULE,
1417 .name = "garmin_gps",
1418 },
1419 .description = "Garmin GPS usb/tty",
1420 .id_table = id_table,
1421 .num_ports = 1,
1422 .open = garmin_open,
1423 .close = garmin_close,
1424 .throttle = garmin_throttle,
1425 .unthrottle = garmin_unthrottle,
1426 .port_probe = garmin_port_probe,
1427 .port_remove = garmin_port_remove,
1428 .write = garmin_write,
1429 .write_room = garmin_write_room,
1430 .write_bulk_callback = garmin_write_bulk_callback,
1431 .read_bulk_callback = garmin_read_bulk_callback,
1432 .read_int_callback = garmin_read_int_callback,
1433 };
1434
1435 static struct usb_serial_driver * const serial_drivers[] = {
1436 &garmin_device, NULL
1437 };
1438
1439 module_usb_serial_driver(serial_drivers, id_table);
1440
1441 MODULE_AUTHOR(DRIVER_AUTHOR);
1442 MODULE_DESCRIPTION(DRIVER_DESC);
1443 MODULE_LICENSE("GPL");
1444
1445 module_param(initial_mode, int, 0444);
1446 MODULE_PARM_DESC(initial_mode, "Initial mode");
1447