drivers/usb/serial/garmin

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

DEFINITIONS
