Linux Audio

Check our new training course

Loading...
v6.8
   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 */
  28static 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 */
 102struct 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 */
 111struct 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 */
 170static int gsp_next_packet(struct garmin_data *garmin_data_p);
 171static 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 */
 176static unsigned char const GARMIN_START_SESSION_REQ[]
 177	= { 0, 0, 0, 0,  5, 0, 0, 0, 0, 0, 0, 0 };
 178static unsigned char const GARMIN_START_SESSION_REPLY[]
 179	= { 0, 0, 0, 0,  6, 0, 0, 0, 4, 0, 0, 0 };
 180static unsigned char const GARMIN_BULK_IN_AVAIL_REPLY[]
 181	= { 0, 0, 0, 0,  2, 0, 0, 0, 0, 0, 0, 0 };
 182static unsigned char const GARMIN_STOP_TRANSFER_REQ[]
 183	= { 20, 0, 0, 0,  10, 0, 0, 0, 2, 0, 0, 0, 0, 0 };
 184static 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
 189static unsigned char const GARMIN_APP_LAYER_REPLY[]
 190	= { 0x14, 0, 0, 0 };
 191static unsigned char const GARMIN_START_PVT_REQ[]
 192	= { 20, 0, 0, 0,  10, 0, 0, 0, 2, 0, 0, 0, 49, 0 };
 193static unsigned char const GARMIN_STOP_PVT_REQ[]
 194	= { 20, 0, 0, 0,  10, 0, 0, 0, 2, 0, 0, 0, 50, 0 };
 
 
 
 
 195static unsigned char const PRIVATE_REQ[]
 196	=    { 0x4B, 0x6E, 0x10, 0x01,  0xFF, 0, 0, 0, 0xFF, 0, 0, 0 };
 197#endif
 198
 199
 200static 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};
 206MODULE_DEVICE_TABLE(usb, id_table);
 207
 208
 209static inline int getLayerId(const __u8 *usbPacket)
 210{
 211	return __le32_to_cpup((__le32 *)(usbPacket));
 212}
 213
 214static inline int getPacketId(const __u8 *usbPacket)
 215{
 216	return __le32_to_cpup((__le32 *)(usbPacket+4));
 217}
 218
 219static 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 */
 229static 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
 242static 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 */
 260static 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 */
 300static 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 */
 316static 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 */
 336static 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 */
 382static 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
 462static 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 */
 585static 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 */
 703static 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 */
 735static 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
 805static 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
 825static 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 */
 851static 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
 867static 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
 898err_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
 907static 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
 930static 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
 950static 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
 976static 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
1042static 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
1114static 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
1125static 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
1161static 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
1208static 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 */
1295static 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
1317static 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
1330static 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 */
1359static 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
1371static 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;
1395err_free:
1396	kfree(garmin_data_p);
1397
1398	return status;
1399}
1400
1401
1402static 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	timer_shutdown_sync(&garmin_data_p->timer);
1409	kfree(garmin_data_p);
 
1410}
1411
1412
1413/* All of the device info needed */
1414static 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
1435static struct usb_serial_driver * const serial_drivers[] = {
1436	&garmin_device, NULL
1437};
1438
1439module_usb_serial_driver(serial_drivers, id_table);
1440
1441MODULE_AUTHOR(DRIVER_AUTHOR);
1442MODULE_DESCRIPTION(DRIVER_DESC);
1443MODULE_LICENSE("GPL");
1444
1445module_param(initial_mode, int, 0444);
1446MODULE_PARM_DESC(initial_mode, "Initial mode");
v4.6
 
   1/*
   2 * Garmin GPS driver
   3 *
   4 * Copyright (C) 2006-2011 Hermann Kneissel herkne@gmx.de
   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/slab.h>
  29#include <linux/timer.h>
  30#include <linux/tty.h>
  31#include <linux/tty_driver.h>
  32#include <linux/tty_flip.h>
  33#include <linux/module.h>
  34#include <linux/spinlock.h>
  35#include <linux/uaccess.h>
  36#include <linux/atomic.h>
  37#include <linux/usb.h>
  38#include <linux/usb/serial.h>
  39
  40/* the mode to be set when the port ist opened */
  41static int initial_mode = 1;
  42
  43#define GARMIN_VENDOR_ID             0x091E
  44
  45/*
  46 * Version Information
  47 */
  48
  49#define VERSION_MAJOR	0
  50#define VERSION_MINOR	36
  51
  52#define _STR(s) #s
  53#define _DRIVER_VERSION(a, b) "v" _STR(a) "." _STR(b)
  54#define DRIVER_VERSION _DRIVER_VERSION(VERSION_MAJOR, VERSION_MINOR)
  55#define DRIVER_AUTHOR "hermann kneissel"
  56#define DRIVER_DESC "garmin gps driver"
  57
  58/* error codes returned by the driver */
  59#define EINVPKT	1000	/* invalid packet structure */
  60
  61
  62/* size of the header of a packet using the usb protocol */
  63#define GARMIN_PKTHDR_LENGTH	12
  64
  65/* max. possible size of a packet using the serial protocol */
  66#define MAX_SERIAL_PKT_SIZ (3 + 255 + 3)
  67
  68/*  max. possible size of a packet with worst case stuffing */
  69#define MAX_SERIAL_PKT_SIZ_STUFFED (MAX_SERIAL_PKT_SIZ + 256)
  70
  71/* size of a buffer able to hold a complete (no stuffing) packet
  72 * (the document protocol does not contain packets with a larger
  73 *  size, but in theory a packet may be 64k+12 bytes - if in
  74 *  later protocol versions larger packet sizes occur, this value
  75 *  should be increased accordingly, so the input buffer is always
  76 *  large enough the store a complete packet inclusive header) */
  77#define GPS_IN_BUFSIZ  (GARMIN_PKTHDR_LENGTH+MAX_SERIAL_PKT_SIZ)
  78
  79/* size of a buffer able to hold a complete (incl. stuffing) packet */
  80#define GPS_OUT_BUFSIZ (GARMIN_PKTHDR_LENGTH+MAX_SERIAL_PKT_SIZ_STUFFED)
  81
  82/* where to place the packet id of a serial packet, so we can
  83 * prepend the usb-packet header without the need to move the
  84 * packets data */
  85#define GSP_INITIAL_OFFSET (GARMIN_PKTHDR_LENGTH-2)
  86
  87/* max. size of incoming private packets (header+1 param) */
  88#define PRIVPKTSIZ (GARMIN_PKTHDR_LENGTH+4)
  89
  90#define GARMIN_LAYERID_TRANSPORT  0
  91#define GARMIN_LAYERID_APPL      20
  92/* our own layer-id to use for some control mechanisms */
  93#define GARMIN_LAYERID_PRIVATE	0x01106E4B
  94
  95#define GARMIN_PKTID_PVT_DATA	51
  96#define GARMIN_PKTID_L001_COMMAND_DATA 10
  97
  98#define CMND_ABORT_TRANSFER 0
  99
 100/* packet ids used in private layer */
 101#define PRIV_PKTID_SET_DEBUG	1
 102#define PRIV_PKTID_SET_MODE	2
 103#define PRIV_PKTID_INFO_REQ	3
 104#define PRIV_PKTID_INFO_RESP	4
 105#define PRIV_PKTID_RESET_REQ	5
 106#define PRIV_PKTID_SET_DEF_MODE	6
 107
 108
 109#define ETX	0x03
 110#define DLE	0x10
 111#define ACK	0x06
 112#define NAK	0x15
 113
 114/* structure used to queue incoming packets */
 115struct garmin_packet {
 116	struct list_head  list;
 117	int               seq;
 118	/* the real size of the data array, always > 0 */
 119	int               size;
 120	__u8              data[1];
 121};
 122
 123/* structure used to keep the current state of the driver */
 124struct garmin_data {
 125	__u8   state;
 126	__u16  flags;
 127	__u8   mode;
 128	__u8   count;
 129	__u8   pkt_id;
 130	__u32  serial_num;
 131	struct timer_list timer;
 132	struct usb_serial_port *port;
 133	int    seq_counter;
 134	int    insize;
 135	int    outsize;
 136	__u8   inbuffer [GPS_IN_BUFSIZ];  /* tty -> usb */
 137	__u8   outbuffer[GPS_OUT_BUFSIZ]; /* usb -> tty */
 138	__u8   privpkt[4*6];
 139	spinlock_t lock;
 140	struct list_head pktlist;
 
 141};
 142
 143
 144#define STATE_NEW            0
 145#define STATE_INITIAL_DELAY  1
 146#define STATE_TIMEOUT        2
 147#define STATE_SESSION_REQ1   3
 148#define STATE_SESSION_REQ2   4
 149#define STATE_ACTIVE         5
 150
 151#define STATE_RESET	     8
 152#define STATE_DISCONNECTED   9
 153#define STATE_WAIT_TTY_ACK  10
 154#define STATE_GSP_WAIT_DATA 11
 155
 156#define MODE_NATIVE          0
 157#define MODE_GARMIN_SERIAL   1
 158
 159/* Flags used in garmin_data.flags: */
 160#define FLAGS_SESSION_REPLY_MASK  0x00C0
 161#define FLAGS_SESSION_REPLY1_SEEN 0x0080
 162#define FLAGS_SESSION_REPLY2_SEEN 0x0040
 163#define FLAGS_BULK_IN_ACTIVE      0x0020
 164#define FLAGS_BULK_IN_RESTART     0x0010
 165#define FLAGS_THROTTLED           0x0008
 166#define APP_REQ_SEEN              0x0004
 167#define APP_RESP_SEEN             0x0002
 168#define CLEAR_HALT_REQUIRED       0x0001
 169
 170#define FLAGS_QUEUING             0x0100
 171#define FLAGS_DROP_DATA           0x0800
 172
 173#define FLAGS_GSP_SKIP            0x1000
 174#define FLAGS_GSP_DLESEEN         0x2000
 175
 176
 177
 178
 179
 180
 181/* function prototypes */
 182static int gsp_next_packet(struct garmin_data *garmin_data_p);
 183static int garmin_write_bulk(struct usb_serial_port *port,
 184			     const unsigned char *buf, int count,
 185			     int dismiss_ack);
 186
 187/* some special packets to be send or received */
 188static unsigned char const GARMIN_START_SESSION_REQ[]
 189	= { 0, 0, 0, 0,  5, 0, 0, 0, 0, 0, 0, 0 };
 190static unsigned char const GARMIN_START_SESSION_REPLY[]
 191	= { 0, 0, 0, 0,  6, 0, 0, 0, 4, 0, 0, 0 };
 192static unsigned char const GARMIN_BULK_IN_AVAIL_REPLY[]
 193	= { 0, 0, 0, 0,  2, 0, 0, 0, 0, 0, 0, 0 };
 
 
 
 
 
 
 
 194static unsigned char const GARMIN_APP_LAYER_REPLY[]
 195	= { 0x14, 0, 0, 0 };
 196static unsigned char const GARMIN_START_PVT_REQ[]
 197	= { 20, 0, 0, 0,  10, 0, 0, 0, 2, 0, 0, 0, 49, 0 };
 198static unsigned char const GARMIN_STOP_PVT_REQ[]
 199	= { 20, 0, 0, 0,  10, 0, 0, 0, 2, 0, 0, 0, 50, 0 };
 200static unsigned char const GARMIN_STOP_TRANSFER_REQ[]
 201	= { 20, 0, 0, 0,  10, 0, 0, 0, 2, 0, 0, 0, 0, 0 };
 202static unsigned char const GARMIN_STOP_TRANSFER_REQ_V2[]
 203	= { 20, 0, 0, 0,  10, 0, 0, 0, 1, 0, 0, 0, 0 };
 204static unsigned char const PRIVATE_REQ[]
 205	=    { 0x4B, 0x6E, 0x10, 0x01,  0xFF, 0, 0, 0, 0xFF, 0, 0, 0 };
 206
 207
 208
 209static const struct usb_device_id id_table[] = {
 210	/* the same device id seems to be used by all
 211	   usb enabled GPS devices */
 212	{ USB_DEVICE(GARMIN_VENDOR_ID, 3) },
 213	{ }					/* Terminating entry */
 214};
 215MODULE_DEVICE_TABLE(usb, id_table);
 216
 217
 218static inline int getLayerId(const __u8 *usbPacket)
 219{
 220	return __le32_to_cpup((__le32 *)(usbPacket));
 221}
 222
 223static inline int getPacketId(const __u8 *usbPacket)
 224{
 225	return __le32_to_cpup((__le32 *)(usbPacket+4));
 226}
 227
 228static inline int getDataLength(const __u8 *usbPacket)
 229{
 230	return __le32_to_cpup((__le32 *)(usbPacket+8));
 231}
 232
 233
 234/*
 235 * check if the usb-packet in buf contains an abort-transfer command.
 236 * (if yes, all queued data will be dropped)
 237 */
 238static inline int isAbortTrfCmnd(const unsigned char *buf)
 239{
 240	if (memcmp(buf, GARMIN_STOP_TRANSFER_REQ,
 241			sizeof(GARMIN_STOP_TRANSFER_REQ)) == 0 ||
 242	    memcmp(buf, GARMIN_STOP_TRANSFER_REQ_V2,
 243			sizeof(GARMIN_STOP_TRANSFER_REQ_V2)) == 0)
 244		return 1;
 245	else
 246		return 0;
 247}
 248
 249
 250
 251static void send_to_tty(struct usb_serial_port *port,
 252			char *data, unsigned int actual_length)
 253{
 254	if (actual_length) {
 255		usb_serial_debug_data(&port->dev, __func__, actual_length, data);
 256		tty_insert_flip_string(&port->port, data, actual_length);
 257		tty_flip_buffer_push(&port->port);
 258	}
 259}
 260
 261
 262/******************************************************************************
 263 * packet queue handling
 264 ******************************************************************************/
 265
 266/*
 267 * queue a received (usb-)packet for later processing
 268 */
 269static int pkt_add(struct garmin_data *garmin_data_p,
 270		   unsigned char *data, unsigned int data_length)
 271{
 272	int state = 0;
 273	int result = 0;
 274	unsigned long flags;
 275	struct garmin_packet *pkt;
 276
 277	/* process only packets containing data ... */
 278	if (data_length) {
 279		pkt = kmalloc(sizeof(struct garmin_packet)+data_length,
 280								GFP_ATOMIC);
 281		if (!pkt)
 282			return 0;
 283
 284		pkt->size = data_length;
 285		memcpy(pkt->data, data, data_length);
 286
 287		spin_lock_irqsave(&garmin_data_p->lock, flags);
 288		garmin_data_p->flags |= FLAGS_QUEUING;
 289		result = list_empty(&garmin_data_p->pktlist);
 290		pkt->seq = garmin_data_p->seq_counter++;
 291		list_add_tail(&pkt->list, &garmin_data_p->pktlist);
 292		state = garmin_data_p->state;
 293		spin_unlock_irqrestore(&garmin_data_p->lock, flags);
 294
 295		dev_dbg(&garmin_data_p->port->dev,
 296			"%s - added: pkt: %d - %d bytes\n", __func__,
 297			pkt->seq, data_length);
 298
 299		/* in serial mode, if someone is waiting for data from
 300		   the device, convert and send the next packet to tty. */
 301		if (result && (state == STATE_GSP_WAIT_DATA))
 302			gsp_next_packet(garmin_data_p);
 303	}
 304	return result;
 305}
 306
 307
 308/* get the next pending packet */
 309static struct garmin_packet *pkt_pop(struct garmin_data *garmin_data_p)
 310{
 311	unsigned long flags;
 312	struct garmin_packet *result = NULL;
 313
 314	spin_lock_irqsave(&garmin_data_p->lock, flags);
 315	if (!list_empty(&garmin_data_p->pktlist)) {
 316		result = (struct garmin_packet *)garmin_data_p->pktlist.next;
 317		list_del(&result->list);
 318	}
 319	spin_unlock_irqrestore(&garmin_data_p->lock, flags);
 320	return result;
 321}
 322
 323
 324/* free up all queued data */
 325static void pkt_clear(struct garmin_data *garmin_data_p)
 326{
 327	unsigned long flags;
 328	struct garmin_packet *result = NULL;
 329
 330	spin_lock_irqsave(&garmin_data_p->lock, flags);
 331	while (!list_empty(&garmin_data_p->pktlist)) {
 332		result = (struct garmin_packet *)garmin_data_p->pktlist.next;
 333		list_del(&result->list);
 334		kfree(result);
 335	}
 336	spin_unlock_irqrestore(&garmin_data_p->lock, flags);
 337}
 338
 339
 340/******************************************************************************
 341 * garmin serial protocol handling handling
 342 ******************************************************************************/
 343
 344/* send an ack packet back to the tty */
 345static int gsp_send_ack(struct garmin_data *garmin_data_p, __u8 pkt_id)
 346{
 347	__u8 pkt[10];
 348	__u8 cksum = 0;
 349	__u8 *ptr = pkt;
 350	unsigned  l = 0;
 351
 352	dev_dbg(&garmin_data_p->port->dev, "%s - pkt-id: 0x%X.\n", __func__,
 353			pkt_id);
 354
 355	*ptr++ = DLE;
 356	*ptr++ = ACK;
 357	cksum += ACK;
 358
 359	*ptr++ = 2;
 360	cksum += 2;
 361
 362	*ptr++ = pkt_id;
 363	cksum += pkt_id;
 364
 365	if (pkt_id == DLE)
 366		*ptr++ = DLE;
 367
 368	*ptr++ = 0;
 369	*ptr++ = (-cksum) & 0xFF;
 370	*ptr++ = DLE;
 371	*ptr++ = ETX;
 372
 373	l = ptr-pkt;
 374
 375	send_to_tty(garmin_data_p->port, pkt, l);
 376	return 0;
 377}
 378
 379
 380
 381/*
 382 * called for a complete packet received from tty layer
 383 *
 384 * the complete packet (pktid ... cksum) is in garmin_data_p->inbuf starting
 385 * at GSP_INITIAL_OFFSET.
 386 *
 387 * count - number of bytes in the input buffer including space reserved for
 388 *         the usb header: GSP_INITIAL_OFFSET + number of bytes in packet
 389 *         (including pkt-id, data-length a. cksum)
 390 */
 391static int gsp_rec_packet(struct garmin_data *garmin_data_p, int count)
 392{
 393	struct device *dev = &garmin_data_p->port->dev;
 394	unsigned long flags;
 395	const __u8 *recpkt = garmin_data_p->inbuffer+GSP_INITIAL_OFFSET;
 396	__le32 *usbdata = (__le32 *) garmin_data_p->inbuffer;
 397	int cksum = 0;
 398	int n = 0;
 399	int pktid = recpkt[0];
 400	int size = recpkt[1];
 401
 402	usb_serial_debug_data(&garmin_data_p->port->dev, __func__,
 403			      count-GSP_INITIAL_OFFSET, recpkt);
 404
 405	if (size != (count-GSP_INITIAL_OFFSET-3)) {
 406		dev_dbg(dev, "%s - invalid size, expected %d bytes, got %d\n",
 407			__func__, size, (count-GSP_INITIAL_OFFSET-3));
 408		return -EINVPKT;
 409	}
 410
 411	cksum += *recpkt++;
 412	cksum += *recpkt++;
 413
 414	/* sanity check, remove after test ... */
 415	if ((__u8 *)&(usbdata[3]) != recpkt) {
 416		dev_dbg(dev, "%s - ptr mismatch %p - %p\n", __func__,
 417			&(usbdata[4]), recpkt);
 418		return -EINVPKT;
 419	}
 420
 421	while (n < size) {
 422		cksum += *recpkt++;
 423		n++;
 424	}
 425
 426	if (((cksum + *recpkt) & 0xff) != 0) {
 427		dev_dbg(dev, "%s - invalid checksum, expected %02x, got %02x\n",
 428			__func__, -cksum & 0xff, *recpkt);
 429		return -EINVPKT;
 430	}
 431
 432	usbdata[0] = __cpu_to_le32(GARMIN_LAYERID_APPL);
 433	usbdata[1] = __cpu_to_le32(pktid);
 434	usbdata[2] = __cpu_to_le32(size);
 435
 436	garmin_write_bulk(garmin_data_p->port, garmin_data_p->inbuffer,
 437			   GARMIN_PKTHDR_LENGTH+size, 0);
 438
 439	/* if this was an abort-transfer command, flush all
 440	   queued data. */
 441	if (isAbortTrfCmnd(garmin_data_p->inbuffer)) {
 442		spin_lock_irqsave(&garmin_data_p->lock, flags);
 443		garmin_data_p->flags |= FLAGS_DROP_DATA;
 444		spin_unlock_irqrestore(&garmin_data_p->lock, flags);
 445		pkt_clear(garmin_data_p);
 446	}
 447
 448	return count;
 449}
 450
 451
 452
 453/*
 454 * Called for data received from tty
 455 *
 456 * buf contains the data read, it may span more than one packet or even
 457 * incomplete packets
 458 *
 459 * input record should be a serial-record, but it may not be complete.
 460 * Copy it into our local buffer, until an etx is seen (or an error
 461 * occurs).
 462 * Once the record is complete, convert into a usb packet and send it
 463 * to the bulk pipe, send an ack back to the tty.
 464 *
 465 * If the input is an ack, just send the last queued packet to the
 466 * tty layer.
 467 *
 468 * if the input is an abort command, drop all queued data.
 469 */
 470
 471static int gsp_receive(struct garmin_data *garmin_data_p,
 472		       const unsigned char *buf, int count)
 473{
 474	struct device *dev = &garmin_data_p->port->dev;
 475	unsigned long flags;
 476	int offs = 0;
 477	int ack_or_nak_seen = 0;
 478	__u8 *dest;
 479	int size;
 480	/* dleSeen: set if last byte read was a DLE */
 481	int dleSeen;
 482	/* skip: if set, skip incoming data until possible start of
 483	 *       new packet
 484	 */
 485	int skip;
 486	__u8 data;
 487
 488	spin_lock_irqsave(&garmin_data_p->lock, flags);
 489	dest = garmin_data_p->inbuffer;
 490	size = garmin_data_p->insize;
 491	dleSeen = garmin_data_p->flags & FLAGS_GSP_DLESEEN;
 492	skip = garmin_data_p->flags & FLAGS_GSP_SKIP;
 493	spin_unlock_irqrestore(&garmin_data_p->lock, flags);
 494
 495	/* dev_dbg(dev, "%s - dle=%d skip=%d size=%d count=%d\n",
 496		__func__, dleSeen, skip, size, count); */
 497
 498	if (size == 0)
 499		size = GSP_INITIAL_OFFSET;
 500
 501	while (offs < count) {
 502
 503		data = *(buf+offs);
 504		offs++;
 505
 506		if (data == DLE) {
 507			if (skip) { /* start of a new pkt */
 508				skip = 0;
 509				size = GSP_INITIAL_OFFSET;
 510				dleSeen = 1;
 511			} else if (dleSeen) {
 512				dest[size++] = data;
 513				dleSeen = 0;
 514			} else {
 515				dleSeen = 1;
 516			}
 517		} else if (data == ETX) {
 518			if (dleSeen) {
 519				/* packet complete */
 520
 521				data = dest[GSP_INITIAL_OFFSET];
 522
 523				if (data == ACK) {
 524					ack_or_nak_seen = ACK;
 525					dev_dbg(dev, "ACK packet complete.\n");
 526				} else if (data == NAK) {
 527					ack_or_nak_seen = NAK;
 528					dev_dbg(dev, "NAK packet complete.\n");
 529				} else {
 530					dev_dbg(dev, "packet complete - id=0x%X.\n",
 531							data);
 532					gsp_rec_packet(garmin_data_p, size);
 533				}
 534
 535				skip = 1;
 536				size = GSP_INITIAL_OFFSET;
 537				dleSeen = 0;
 538			} else {
 539				dest[size++] = data;
 540			}
 541		} else if (!skip) {
 542
 543			if (dleSeen) {
 544				size = GSP_INITIAL_OFFSET;
 545				dleSeen = 0;
 546			}
 547
 548			dest[size++] = data;
 549		}
 550
 551		if (size >= GPS_IN_BUFSIZ) {
 552			dev_dbg(dev, "%s - packet too large.\n", __func__);
 553			skip = 1;
 554			size = GSP_INITIAL_OFFSET;
 555			dleSeen = 0;
 556		}
 557	}
 558
 559	spin_lock_irqsave(&garmin_data_p->lock, flags);
 560
 561	garmin_data_p->insize = size;
 562
 563	/* copy flags back to structure */
 564	if (skip)
 565		garmin_data_p->flags |= FLAGS_GSP_SKIP;
 566	else
 567		garmin_data_p->flags &= ~FLAGS_GSP_SKIP;
 568
 569	if (dleSeen)
 570		garmin_data_p->flags |= FLAGS_GSP_DLESEEN;
 571	else
 572		garmin_data_p->flags &= ~FLAGS_GSP_DLESEEN;
 573
 574	spin_unlock_irqrestore(&garmin_data_p->lock, flags);
 575
 576	if (ack_or_nak_seen) {
 577		if (gsp_next_packet(garmin_data_p) > 0)
 578			garmin_data_p->state = STATE_ACTIVE;
 579		else
 580			garmin_data_p->state = STATE_GSP_WAIT_DATA;
 581	}
 582	return count;
 583}
 584
 585
 586
 587/*
 588 * Sends a usb packet to the tty
 589 *
 590 * Assumes, that all packages and at an usb-packet boundary.
 591 *
 592 * return <0 on error, 0 if packet is incomplete or > 0 if packet was sent
 593 */
 594static int gsp_send(struct garmin_data *garmin_data_p,
 595		    const unsigned char *buf, int count)
 596{
 597	struct device *dev = &garmin_data_p->port->dev;
 598	const unsigned char *src;
 599	unsigned char *dst;
 600	int pktid = 0;
 601	int datalen = 0;
 602	int cksum = 0;
 603	int i = 0;
 604	int k;
 605
 606	dev_dbg(dev, "%s - state %d - %d bytes.\n", __func__,
 607		garmin_data_p->state, count);
 608
 609	k = garmin_data_p->outsize;
 610	if ((k+count) > GPS_OUT_BUFSIZ) {
 611		dev_dbg(dev, "packet too large\n");
 612		garmin_data_p->outsize = 0;
 613		return -4;
 614	}
 615
 616	memcpy(garmin_data_p->outbuffer+k, buf, count);
 617	k += count;
 618	garmin_data_p->outsize = k;
 619
 620	if (k >= GARMIN_PKTHDR_LENGTH) {
 621		pktid  = getPacketId(garmin_data_p->outbuffer);
 622		datalen = getDataLength(garmin_data_p->outbuffer);
 623		i = GARMIN_PKTHDR_LENGTH + datalen;
 624		if (k < i)
 625			return 0;
 626	} else {
 627		return 0;
 628	}
 629
 630	dev_dbg(dev, "%s - %d bytes in buffer, %d bytes in pkt.\n", __func__, k, i);
 631
 632	/* garmin_data_p->outbuffer now contains a complete packet */
 633
 634	usb_serial_debug_data(&garmin_data_p->port->dev, __func__, k,
 635			      garmin_data_p->outbuffer);
 636
 637	garmin_data_p->outsize = 0;
 638
 639	if (getLayerId(garmin_data_p->outbuffer) != GARMIN_LAYERID_APPL) {
 640		dev_dbg(dev, "not an application packet (%d)\n",
 641				getLayerId(garmin_data_p->outbuffer));
 642		return -1;
 643	}
 644
 645	if (pktid > 255) {
 646		dev_dbg(dev, "packet-id %d too large\n", pktid);
 647		return -2;
 648	}
 649
 650	if (datalen > 255) {
 651		dev_dbg(dev, "packet-size %d too large\n", datalen);
 652		return -3;
 653	}
 654
 655	/* the serial protocol should be able to handle this packet */
 656
 657	k = 0;
 658	src = garmin_data_p->outbuffer+GARMIN_PKTHDR_LENGTH;
 659	for (i = 0; i < datalen; i++) {
 660		if (*src++ == DLE)
 661			k++;
 662	}
 663
 664	src = garmin_data_p->outbuffer+GARMIN_PKTHDR_LENGTH;
 665	if (k > (GARMIN_PKTHDR_LENGTH-2)) {
 666		/* can't add stuffing DLEs in place, move data to end
 667		   of buffer ... */
 668		dst = garmin_data_p->outbuffer+GPS_OUT_BUFSIZ-datalen;
 669		memcpy(dst, src, datalen);
 670		src = dst;
 671	}
 672
 673	dst = garmin_data_p->outbuffer;
 674
 675	*dst++ = DLE;
 676	*dst++ = pktid;
 677	cksum += pktid;
 678	*dst++ = datalen;
 679	cksum += datalen;
 680	if (datalen == DLE)
 681		*dst++ = DLE;
 682
 683	for (i = 0; i < datalen; i++) {
 684		__u8 c = *src++;
 685		*dst++ = c;
 686		cksum += c;
 687		if (c == DLE)
 688			*dst++ = DLE;
 689	}
 690
 691	cksum = -cksum & 0xFF;
 692	*dst++ = cksum;
 693	if (cksum == DLE)
 694		*dst++ = DLE;
 695	*dst++ = DLE;
 696	*dst++ = ETX;
 697
 698	i = dst-garmin_data_p->outbuffer;
 699
 700	send_to_tty(garmin_data_p->port, garmin_data_p->outbuffer, i);
 701
 702	garmin_data_p->pkt_id = pktid;
 703	garmin_data_p->state  = STATE_WAIT_TTY_ACK;
 704
 705	return i;
 706}
 707
 708
 709/*
 710 * Process the next pending data packet - if there is one
 711 */
 712static int gsp_next_packet(struct garmin_data *garmin_data_p)
 713{
 714	int result = 0;
 715	struct garmin_packet *pkt = NULL;
 716
 717	while ((pkt = pkt_pop(garmin_data_p)) != NULL) {
 718		dev_dbg(&garmin_data_p->port->dev, "%s - next pkt: %d\n", __func__, pkt->seq);
 719		result = gsp_send(garmin_data_p, pkt->data, pkt->size);
 720		if (result > 0) {
 721			kfree(pkt);
 722			return result;
 723		}
 724		kfree(pkt);
 725	}
 726	return result;
 727}
 728
 729
 730
 731/******************************************************************************
 732 * garmin native mode
 733 ******************************************************************************/
 734
 735
 736/*
 737 * Called for data received from tty
 738 *
 739 * The input data is expected to be in garmin usb-packet format.
 740 *
 741 * buf contains the data read, it may span more than one packet
 742 * or even incomplete packets
 743 */
 744static int nat_receive(struct garmin_data *garmin_data_p,
 745		       const unsigned char *buf, int count)
 746{
 747	unsigned long flags;
 748	__u8 *dest;
 749	int offs = 0;
 750	int result = count;
 751	int len;
 752
 753	while (offs < count) {
 754		/* if buffer contains header, copy rest of data */
 755		if (garmin_data_p->insize >= GARMIN_PKTHDR_LENGTH)
 756			len = GARMIN_PKTHDR_LENGTH
 757			      +getDataLength(garmin_data_p->inbuffer);
 758		else
 759			len = GARMIN_PKTHDR_LENGTH;
 760
 761		if (len >= GPS_IN_BUFSIZ) {
 762			/* seems to be an invalid packet, ignore rest
 763			   of input */
 764			dev_dbg(&garmin_data_p->port->dev,
 765				"%s - packet size too large: %d\n",
 766				__func__, len);
 767			garmin_data_p->insize = 0;
 768			count = 0;
 769			result = -EINVPKT;
 770		} else {
 771			len -= garmin_data_p->insize;
 772			if (len > (count-offs))
 773				len = (count-offs);
 774			if (len > 0) {
 775				dest = garmin_data_p->inbuffer
 776						+ garmin_data_p->insize;
 777				memcpy(dest, buf+offs, len);
 778				garmin_data_p->insize += len;
 779				offs += len;
 780			}
 781		}
 782
 783		/* do we have a complete packet ? */
 784		if (garmin_data_p->insize >= GARMIN_PKTHDR_LENGTH) {
 785			len = GARMIN_PKTHDR_LENGTH+
 786			   getDataLength(garmin_data_p->inbuffer);
 787			if (garmin_data_p->insize >= len) {
 788				garmin_write_bulk(garmin_data_p->port,
 789						   garmin_data_p->inbuffer,
 790						   len, 0);
 791				garmin_data_p->insize = 0;
 792
 793				/* if this was an abort-transfer command,
 794				   flush all queued data. */
 795				if (isAbortTrfCmnd(garmin_data_p->inbuffer)) {
 796					spin_lock_irqsave(&garmin_data_p->lock,
 797									flags);
 798					garmin_data_p->flags |= FLAGS_DROP_DATA;
 799					spin_unlock_irqrestore(
 800						&garmin_data_p->lock, flags);
 801					pkt_clear(garmin_data_p);
 802				}
 803			}
 804		}
 805	}
 806	return result;
 807}
 808
 809
 810/******************************************************************************
 811 * private packets
 812 ******************************************************************************/
 813
 814static void priv_status_resp(struct usb_serial_port *port)
 815{
 816	struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
 817	__le32 *pkt = (__le32 *)garmin_data_p->privpkt;
 818
 819	pkt[0] = __cpu_to_le32(GARMIN_LAYERID_PRIVATE);
 820	pkt[1] = __cpu_to_le32(PRIV_PKTID_INFO_RESP);
 821	pkt[2] = __cpu_to_le32(12);
 822	pkt[3] = __cpu_to_le32(VERSION_MAJOR << 16 | VERSION_MINOR);
 823	pkt[4] = __cpu_to_le32(garmin_data_p->mode);
 824	pkt[5] = __cpu_to_le32(garmin_data_p->serial_num);
 825
 826	send_to_tty(port, (__u8 *)pkt, 6 * 4);
 827}
 828
 829
 830/******************************************************************************
 831 * Garmin specific driver functions
 832 ******************************************************************************/
 833
 834static int process_resetdev_request(struct usb_serial_port *port)
 835{
 836	unsigned long flags;
 837	int status;
 838	struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
 839
 840	spin_lock_irqsave(&garmin_data_p->lock, flags);
 841	garmin_data_p->flags &= ~(CLEAR_HALT_REQUIRED);
 842	garmin_data_p->state = STATE_RESET;
 843	garmin_data_p->serial_num = 0;
 844	spin_unlock_irqrestore(&garmin_data_p->lock, flags);
 845
 846	usb_kill_urb(port->interrupt_in_urb);
 847	dev_dbg(&port->dev, "%s - usb_reset_device\n", __func__);
 848	status = usb_reset_device(port->serial->dev);
 849	if (status)
 850		dev_dbg(&port->dev, "%s - usb_reset_device failed: %d\n",
 851			__func__, status);
 852	return status;
 853}
 854
 855
 856
 857/*
 858 * clear all cached data
 859 */
 860static int garmin_clear(struct garmin_data *garmin_data_p)
 861{
 862	unsigned long flags;
 863
 864	/* flush all queued data */
 865	pkt_clear(garmin_data_p);
 866
 867	spin_lock_irqsave(&garmin_data_p->lock, flags);
 868	garmin_data_p->insize = 0;
 869	garmin_data_p->outsize = 0;
 870	spin_unlock_irqrestore(&garmin_data_p->lock, flags);
 871
 872	return 0;
 873}
 874
 875
 876static int garmin_init_session(struct usb_serial_port *port)
 877{
 878	struct usb_serial *serial = port->serial;
 879	struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
 880	int status = 0;
 881	int i = 0;
 882
 883	if (status == 0) {
 884		usb_kill_urb(port->interrupt_in_urb);
 885
 886		dev_dbg(&serial->dev->dev, "%s - adding interrupt input\n", __func__);
 887		status = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 888		if (status)
 889			dev_err(&serial->dev->dev,
 890			  "%s - failed submitting interrupt urb, error %d\n",
 891							__func__, status);
 892	}
 893
 894	/*
 895	 * using the initialization method from gpsbabel. See comments in
 896	 * gpsbabel/jeeps/gpslibusb.c gusb_reset_toggles()
 897	 */
 898	if (status == 0) {
 899		dev_dbg(&serial->dev->dev, "%s - starting session ...\n", __func__);
 900		garmin_data_p->state = STATE_ACTIVE;
 901
 902		for (i = 0; i < 3; i++) {
 903			status = garmin_write_bulk(port,
 904					GARMIN_START_SESSION_REQ,
 905					sizeof(GARMIN_START_SESSION_REQ), 0);
 
 906
 907			if (status < 0)
 908				break;
 909		}
 910
 911		if (status > 0)
 912			status = 0;
 913	}
 914
 915	return status;
 916}
 917
 918
 919
 920static int garmin_open(struct tty_struct *tty, struct usb_serial_port *port)
 921{
 922	unsigned long flags;
 923	int status = 0;
 924	struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
 925
 926	spin_lock_irqsave(&garmin_data_p->lock, flags);
 927	garmin_data_p->mode  = initial_mode;
 928	garmin_data_p->count = 0;
 929	garmin_data_p->flags &= FLAGS_SESSION_REPLY1_SEEN;
 930	spin_unlock_irqrestore(&garmin_data_p->lock, flags);
 931
 932	/* shutdown any bulk reads that might be going on */
 933	usb_kill_urb(port->write_urb);
 934	usb_kill_urb(port->read_urb);
 935
 936	if (garmin_data_p->state == STATE_RESET)
 937		status = garmin_init_session(port);
 938
 939	garmin_data_p->state = STATE_ACTIVE;
 940	return status;
 941}
 942
 943
 944static void garmin_close(struct usb_serial_port *port)
 945{
 946	struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
 947
 948	dev_dbg(&port->dev, "%s - mode=%d state=%d flags=0x%X\n",
 949		__func__, garmin_data_p->mode, garmin_data_p->state,
 950		garmin_data_p->flags);
 951
 952	garmin_clear(garmin_data_p);
 953
 954	/* shutdown our urbs */
 955	usb_kill_urb(port->read_urb);
 956	usb_kill_urb(port->write_urb);
 957
 958	/* keep reset state so we know that we must start a new session */
 959	if (garmin_data_p->state != STATE_RESET)
 960		garmin_data_p->state = STATE_DISCONNECTED;
 961}
 962
 963
 964static void garmin_write_bulk_callback(struct urb *urb)
 965{
 966	struct usb_serial_port *port = urb->context;
 967
 968	if (port) {
 969		struct garmin_data *garmin_data_p =
 970					usb_get_serial_port_data(port);
 971
 972		if (getLayerId(urb->transfer_buffer) == GARMIN_LAYERID_APPL) {
 973
 974			if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
 975				gsp_send_ack(garmin_data_p,
 976					((__u8 *)urb->transfer_buffer)[4]);
 977			}
 978		}
 979		usb_serial_port_softint(port);
 980	}
 981
 982	/* Ignore errors that resulted from garmin_write_bulk with
 983	   dismiss_ack = 1 */
 984
 985	/* free up the transfer buffer, as usb_free_urb() does not do this */
 986	kfree(urb->transfer_buffer);
 987}
 988
 989
 990static int garmin_write_bulk(struct usb_serial_port *port,
 991			      const unsigned char *buf, int count,
 992			      int dismiss_ack)
 993{
 994	unsigned long flags;
 995	struct usb_serial *serial = port->serial;
 996	struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
 997	struct urb *urb;
 998	unsigned char *buffer;
 999	int status;
1000
1001	spin_lock_irqsave(&garmin_data_p->lock, flags);
1002	garmin_data_p->flags &= ~FLAGS_DROP_DATA;
1003	spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1004
1005	buffer = kmalloc(count, GFP_ATOMIC);
1006	if (!buffer)
1007		return -ENOMEM;
1008
1009	urb = usb_alloc_urb(0, GFP_ATOMIC);
1010	if (!urb) {
1011		kfree(buffer);
1012		return -ENOMEM;
1013	}
1014
1015	memcpy(buffer, buf, count);
1016
1017	usb_serial_debug_data(&port->dev, __func__, count, buffer);
1018
1019	usb_fill_bulk_urb(urb, serial->dev,
1020				usb_sndbulkpipe(serial->dev,
1021					port->bulk_out_endpointAddress),
1022				buffer, count,
1023				garmin_write_bulk_callback,
1024				dismiss_ack ? NULL : port);
1025	urb->transfer_flags |= URB_ZERO_PACKET;
1026
1027	if (getLayerId(buffer) == GARMIN_LAYERID_APPL) {
1028
1029		spin_lock_irqsave(&garmin_data_p->lock, flags);
1030		garmin_data_p->flags |= APP_REQ_SEEN;
1031		spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1032
1033		if (garmin_data_p->mode == MODE_GARMIN_SERIAL)  {
1034			pkt_clear(garmin_data_p);
1035			garmin_data_p->state = STATE_GSP_WAIT_DATA;
1036		}
1037	}
1038
1039	/* send it down the pipe */
 
1040	status = usb_submit_urb(urb, GFP_ATOMIC);
1041	if (status) {
1042		dev_err(&port->dev,
1043		   "%s - usb_submit_urb(write bulk) failed with status = %d\n",
1044				__func__, status);
1045		count = status;
 
 
1046	}
1047
1048	/* we are done with this urb, so let the host driver
1049	 * really free it when it is finished with it */
1050	usb_free_urb(urb);
1051
1052	return count;
1053}
1054
1055static int garmin_write(struct tty_struct *tty, struct usb_serial_port *port,
1056					 const unsigned char *buf, int count)
1057{
1058	struct device *dev = &port->dev;
1059	int pktid, pktsiz, len;
1060	struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1061	__le32 *privpkt = (__le32 *)garmin_data_p->privpkt;
1062
1063	usb_serial_debug_data(dev, __func__, count, buf);
1064
1065	if (garmin_data_p->state == STATE_RESET)
1066		return -EIO;
1067
1068	/* check for our private packets */
1069	if (count >= GARMIN_PKTHDR_LENGTH) {
1070		len = PRIVPKTSIZ;
1071		if (count < len)
1072			len = count;
1073
1074		memcpy(garmin_data_p->privpkt, buf, len);
1075
1076		pktsiz = getDataLength(garmin_data_p->privpkt);
1077		pktid  = getPacketId(garmin_data_p->privpkt);
1078
1079		if (count == (GARMIN_PKTHDR_LENGTH + pktsiz) &&
1080				getLayerId(garmin_data_p->privpkt) ==
1081						GARMIN_LAYERID_PRIVATE) {
1082
1083			dev_dbg(dev, "%s - processing private request %d\n",
1084				__func__, pktid);
1085
1086			/* drop all unfinished transfers */
1087			garmin_clear(garmin_data_p);
1088
1089			switch (pktid) {
1090			case PRIV_PKTID_SET_MODE:
1091				if (pktsiz != 4)
1092					return -EINVPKT;
1093				garmin_data_p->mode = __le32_to_cpu(privpkt[3]);
1094				dev_dbg(dev, "%s - mode set to %d\n",
1095					__func__, garmin_data_p->mode);
1096				break;
1097
1098			case PRIV_PKTID_INFO_REQ:
1099				priv_status_resp(port);
1100				break;
1101
1102			case PRIV_PKTID_RESET_REQ:
1103				process_resetdev_request(port);
1104				break;
1105
1106			case PRIV_PKTID_SET_DEF_MODE:
1107				if (pktsiz != 4)
1108					return -EINVPKT;
1109				initial_mode = __le32_to_cpu(privpkt[3]);
1110				dev_dbg(dev, "%s - initial_mode set to %d\n",
1111					__func__,
1112					garmin_data_p->mode);
1113				break;
1114			}
1115			return count;
1116		}
1117	}
1118
1119	if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
1120		return gsp_receive(garmin_data_p, buf, count);
1121	} else {	/* MODE_NATIVE */
1122		return nat_receive(garmin_data_p, buf, count);
1123	}
1124}
1125
1126
1127static int garmin_write_room(struct tty_struct *tty)
1128{
1129	struct usb_serial_port *port = tty->driver_data;
1130	/*
1131	 * Report back the bytes currently available in the output buffer.
1132	 */
1133	struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1134	return GPS_OUT_BUFSIZ-garmin_data_p->outsize;
1135}
1136
1137
1138static void garmin_read_process(struct garmin_data *garmin_data_p,
1139				 unsigned char *data, unsigned data_length,
1140				 int bulk_data)
1141{
1142	unsigned long flags;
1143
1144	if (garmin_data_p->flags & FLAGS_DROP_DATA) {
1145		/* abort-transfer cmd is active */
1146		dev_dbg(&garmin_data_p->port->dev, "%s - pkt dropped\n", __func__);
1147	} else if (garmin_data_p->state != STATE_DISCONNECTED &&
1148		garmin_data_p->state != STATE_RESET) {
1149
1150		/* if throttling is active or postprecessing is required
1151		   put the received data in the input queue, otherwise
1152		   send it directly to the tty port */
1153		if (garmin_data_p->flags & FLAGS_QUEUING) {
1154			pkt_add(garmin_data_p, data, data_length);
1155		} else if (bulk_data ||
1156			   getLayerId(data) == GARMIN_LAYERID_APPL) {
1157
1158			spin_lock_irqsave(&garmin_data_p->lock, flags);
1159			garmin_data_p->flags |= APP_RESP_SEEN;
1160			spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1161
1162			if (garmin_data_p->mode == MODE_GARMIN_SERIAL) {
1163				pkt_add(garmin_data_p, data, data_length);
1164			} else {
1165				send_to_tty(garmin_data_p->port, data,
1166						data_length);
1167			}
1168		}
1169		/* ignore system layer packets ... */
1170	}
1171}
1172
1173
1174static void garmin_read_bulk_callback(struct urb *urb)
1175{
1176	unsigned long flags;
1177	struct usb_serial_port *port = urb->context;
1178	struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1179	unsigned char *data = urb->transfer_buffer;
1180	int status = urb->status;
1181	int retval;
1182
1183	if (status) {
1184		dev_dbg(&urb->dev->dev, "%s - nonzero read bulk status received: %d\n",
1185			__func__, status);
1186		return;
1187	}
1188
1189	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
1190
1191	garmin_read_process(garmin_data_p, data, urb->actual_length, 1);
1192
1193	if (urb->actual_length == 0 &&
1194			(garmin_data_p->flags & FLAGS_BULK_IN_RESTART) != 0) {
1195		spin_lock_irqsave(&garmin_data_p->lock, flags);
1196		garmin_data_p->flags &= ~FLAGS_BULK_IN_RESTART;
1197		spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1198		retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1199		if (retval)
1200			dev_err(&port->dev,
1201				"%s - failed resubmitting read urb, error %d\n",
1202				__func__, retval);
1203	} else if (urb->actual_length > 0) {
1204		/* Continue trying to read until nothing more is received  */
1205		if ((garmin_data_p->flags & FLAGS_THROTTLED) == 0) {
1206			retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1207			if (retval)
1208				dev_err(&port->dev,
1209					"%s - failed resubmitting read urb, error %d\n",
1210					__func__, retval);
1211		}
1212	} else {
1213		dev_dbg(&port->dev, "%s - end of bulk data\n", __func__);
1214		spin_lock_irqsave(&garmin_data_p->lock, flags);
1215		garmin_data_p->flags &= ~FLAGS_BULK_IN_ACTIVE;
1216		spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1217	}
1218}
1219
1220
1221static void garmin_read_int_callback(struct urb *urb)
1222{
1223	unsigned long flags;
1224	int retval;
1225	struct usb_serial_port *port = urb->context;
1226	struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1227	unsigned char *data = urb->transfer_buffer;
1228	int status = urb->status;
1229
1230	switch (status) {
1231	case 0:
1232		/* success */
1233		break;
1234	case -ECONNRESET:
1235	case -ENOENT:
1236	case -ESHUTDOWN:
1237		/* this urb is terminated, clean up */
1238		dev_dbg(&urb->dev->dev, "%s - urb shutting down with status: %d\n",
1239			__func__, status);
1240		return;
1241	default:
1242		dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n",
1243			__func__, status);
1244		return;
1245	}
1246
1247	usb_serial_debug_data(&port->dev, __func__, urb->actual_length,
1248			      urb->transfer_buffer);
1249
1250	if (urb->actual_length == sizeof(GARMIN_BULK_IN_AVAIL_REPLY) &&
1251		memcmp(data, GARMIN_BULK_IN_AVAIL_REPLY,
1252				sizeof(GARMIN_BULK_IN_AVAIL_REPLY)) == 0) {
1253
1254		dev_dbg(&port->dev, "%s - bulk data available.\n", __func__);
1255
1256		if ((garmin_data_p->flags & FLAGS_BULK_IN_ACTIVE) == 0) {
1257
1258			/* bulk data available */
1259			retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1260			if (retval) {
1261				dev_err(&port->dev,
1262				 "%s - failed submitting read urb, error %d\n",
1263							__func__, retval);
1264			} else {
1265				spin_lock_irqsave(&garmin_data_p->lock, flags);
1266				garmin_data_p->flags |= FLAGS_BULK_IN_ACTIVE;
1267				spin_unlock_irqrestore(&garmin_data_p->lock,
1268									flags);
1269			}
1270		} else {
1271			/* bulk-in transfer still active */
1272			spin_lock_irqsave(&garmin_data_p->lock, flags);
1273			garmin_data_p->flags |= FLAGS_BULK_IN_RESTART;
1274			spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1275		}
1276
1277	} else if (urb->actual_length == (4+sizeof(GARMIN_START_SESSION_REPLY))
1278			 && memcmp(data, GARMIN_START_SESSION_REPLY,
1279				 sizeof(GARMIN_START_SESSION_REPLY)) == 0) {
1280
1281		spin_lock_irqsave(&garmin_data_p->lock, flags);
1282		garmin_data_p->flags |= FLAGS_SESSION_REPLY1_SEEN;
1283		spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1284
1285		/* save the serial number */
1286		garmin_data_p->serial_num = __le32_to_cpup(
1287					(__le32 *)(data+GARMIN_PKTHDR_LENGTH));
1288
1289		dev_dbg(&port->dev, "%s - start-of-session reply seen - serial %u.\n",
1290			__func__, garmin_data_p->serial_num);
1291	}
1292
1293	garmin_read_process(garmin_data_p, data, urb->actual_length, 0);
1294
1295	retval = usb_submit_urb(urb, GFP_ATOMIC);
1296	if (retval)
1297		dev_err(&urb->dev->dev,
1298			"%s - Error %d submitting interrupt urb\n",
1299			__func__, retval);
1300}
1301
1302
1303/*
1304 * Sends the next queued packt to the tty port (garmin native mode only)
1305 * and then sets a timer to call itself again until all queued data
1306 * is sent.
1307 */
1308static int garmin_flush_queue(struct garmin_data *garmin_data_p)
1309{
1310	unsigned long flags;
1311	struct garmin_packet *pkt;
1312
1313	if ((garmin_data_p->flags & FLAGS_THROTTLED) == 0) {
1314		pkt = pkt_pop(garmin_data_p);
1315		if (pkt != NULL) {
1316			send_to_tty(garmin_data_p->port, pkt->data, pkt->size);
1317			kfree(pkt);
1318			mod_timer(&garmin_data_p->timer, (1)+jiffies);
1319
1320		} else {
1321			spin_lock_irqsave(&garmin_data_p->lock, flags);
1322			garmin_data_p->flags &= ~FLAGS_QUEUING;
1323			spin_unlock_irqrestore(&garmin_data_p->lock, flags);
1324		}
1325	}
1326	return 0;
1327}
1328
1329
1330static void garmin_throttle(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
1335	/* set flag, data received will be put into a queue
1336	   for later processing */
1337	spin_lock_irq(&garmin_data_p->lock);
1338	garmin_data_p->flags |= FLAGS_QUEUING|FLAGS_THROTTLED;
1339	spin_unlock_irq(&garmin_data_p->lock);
1340}
1341
1342
1343static void garmin_unthrottle(struct tty_struct *tty)
1344{
1345	struct usb_serial_port *port = tty->driver_data;
1346	struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1347	int status;
1348
1349	spin_lock_irq(&garmin_data_p->lock);
1350	garmin_data_p->flags &= ~FLAGS_THROTTLED;
1351	spin_unlock_irq(&garmin_data_p->lock);
1352
1353	/* in native mode send queued data to tty, in
1354	   serial mode nothing needs to be done here */
1355	if (garmin_data_p->mode == MODE_NATIVE)
1356		garmin_flush_queue(garmin_data_p);
1357
1358	if ((garmin_data_p->flags & FLAGS_BULK_IN_ACTIVE) != 0) {
1359		status = usb_submit_urb(port->read_urb, GFP_KERNEL);
1360		if (status)
1361			dev_err(&port->dev,
1362				"%s - failed resubmitting read urb, error %d\n",
1363				__func__, status);
1364	}
1365}
1366
1367/*
1368 * The timer is currently only used to send queued packets to
1369 * the tty in cases where the protocol provides no own handshaking
1370 * to initiate the transfer.
1371 */
1372static void timeout_handler(unsigned long data)
1373{
1374	struct garmin_data *garmin_data_p = (struct garmin_data *) data;
1375
1376	/* send the next queued packet to the tty port */
1377	if (garmin_data_p->mode == MODE_NATIVE)
1378		if (garmin_data_p->flags & FLAGS_QUEUING)
1379			garmin_flush_queue(garmin_data_p);
1380}
1381
1382
1383
1384static int garmin_port_probe(struct usb_serial_port *port)
1385{
1386	int status;
1387	struct garmin_data *garmin_data_p;
1388
1389	garmin_data_p = kzalloc(sizeof(struct garmin_data), GFP_KERNEL);
1390	if (!garmin_data_p)
1391		return -ENOMEM;
1392
1393	init_timer(&garmin_data_p->timer);
1394	spin_lock_init(&garmin_data_p->lock);
1395	INIT_LIST_HEAD(&garmin_data_p->pktlist);
1396	/* garmin_data_p->timer.expires = jiffies + session_timeout; */
1397	garmin_data_p->timer.data = (unsigned long)garmin_data_p;
1398	garmin_data_p->timer.function = timeout_handler;
1399	garmin_data_p->port = port;
1400	garmin_data_p->state = 0;
1401	garmin_data_p->flags = 0;
1402	garmin_data_p->count = 0;
 
1403	usb_set_serial_port_data(port, garmin_data_p);
1404
1405	status = garmin_init_session(port);
 
 
 
 
 
 
1406
1407	return status;
1408}
1409
1410
1411static int garmin_port_remove(struct usb_serial_port *port)
1412{
1413	struct garmin_data *garmin_data_p = usb_get_serial_port_data(port);
1414
 
1415	usb_kill_urb(port->interrupt_in_urb);
1416	del_timer_sync(&garmin_data_p->timer);
1417	kfree(garmin_data_p);
1418	return 0;
1419}
1420
1421
1422/* All of the device info needed */
1423static struct usb_serial_driver garmin_device = {
1424	.driver = {
1425		.owner       = THIS_MODULE,
1426		.name        = "garmin_gps",
1427	},
1428	.description         = "Garmin GPS usb/tty",
1429	.id_table            = id_table,
1430	.num_ports           = 1,
1431	.open                = garmin_open,
1432	.close               = garmin_close,
1433	.throttle            = garmin_throttle,
1434	.unthrottle          = garmin_unthrottle,
1435	.port_probe		= garmin_port_probe,
1436	.port_remove		= garmin_port_remove,
1437	.write               = garmin_write,
1438	.write_room          = garmin_write_room,
1439	.write_bulk_callback = garmin_write_bulk_callback,
1440	.read_bulk_callback  = garmin_read_bulk_callback,
1441	.read_int_callback   = garmin_read_int_callback,
1442};
1443
1444static struct usb_serial_driver * const serial_drivers[] = {
1445	&garmin_device, NULL
1446};
1447
1448module_usb_serial_driver(serial_drivers, id_table);
1449
1450MODULE_AUTHOR(DRIVER_AUTHOR);
1451MODULE_DESCRIPTION(DRIVER_DESC);
1452MODULE_LICENSE("GPL");
1453
1454module_param(initial_mode, int, S_IRUGO);
1455MODULE_PARM_DESC(initial_mode, "Initial mode");