drivers/input/joystick/grip_mp.c

   1 /*
   2  * $Id: grip_mp.c,v 1.9 2002/07/20 19:28:45 bonnland Exp $
   3  *
   4  *  Driver for the Gravis Grip Multiport, a gamepad "hub" that
   5  *  connects up to four 9-pin digital gamepads/joysticks.
   6  *  Driver tested on SMP and UP kernel versions 2.4.18-4 and 2.4.18-5.
   7  *
   8  *  Thanks to Chris Gassib for helpful advice.
   9  *
  10  *  Copyright (c)      2002 Brian Bonnlander, Bill Soudan
  11  *  Copyright (c) 1998-2000 Vojtech Pavlik
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/init.h>
  17 #include <linux/slab.h>
  18 #include <linux/gameport.h>
  19 #include <linux/input.h>
  20 #include <linux/delay.h>
  21 #include <linux/proc_fs.h>
  22 #include <linux/jiffies.h>
  23
  24 #define DRIVER_DESC     "Gravis Grip Multiport driver"
  25
  26 MODULE_AUTHOR("Brian Bonnlander");
  27 MODULE_DESCRIPTION(DRIVER_DESC);
  28 MODULE_LICENSE("GPL");
  29
  30 #ifdef GRIP_DEBUG
  31 #define dbg(format, arg...) printk(KERN_ERR __FILE__ ": " format "\n" , ## arg)
  32 #else
  33 #define dbg(format, arg...) do {} while (0)
  34 #endif
  35
  36 #define GRIP_MAX_PORTS  4
  37 /*
  38  * Grip multiport state
  39  */
  40
  41 struct grip_port {
  42         struct input_dev *dev;
  43         int mode;
  44         int registered;
  45
  46         /* individual gamepad states */
  47         int buttons;
  48         int xaxes;
  49         int yaxes;
  50         int dirty;     /* has the state been updated? */
  51 };
  52
  53 struct grip_mp {
  54         struct gameport *gameport;
  55         struct grip_port *port[GRIP_MAX_PORTS];
  56         int reads;
  57         int bads;
  58 };
  59
  60 /*
  61  * Multiport packet interpretation
  62  */
  63
  64 #define PACKET_FULL          0x80000000       /* packet is full                        */
  65 #define PACKET_IO_FAST       0x40000000       /* 3 bits per gameport read              */
  66 #define PACKET_IO_SLOW       0x20000000       /* 1 bit per gameport read               */
  67 #define PACKET_MP_MORE       0x04000000       /* multiport wants to send more          */
  68 #define PACKET_MP_DONE       0x02000000       /* multiport done sending                */
  69
  70 /*
  71  * Packet status code interpretation
  72  */
  73
  74 #define IO_GOT_PACKET        0x0100           /* Got a packet                           */
  75 #define IO_MODE_FAST         0x0200           /* Used 3 data bits per gameport read     */
  76 #define IO_SLOT_CHANGE       0x0800           /* Multiport physical slot status changed */
  77 #define IO_DONE              0x1000           /* Multiport is done sending packets      */
  78 #define IO_RETRY             0x4000           /* Try again later to get packet          */
  79 #define IO_RESET             0x8000           /* Force multiport to resend all packets  */
  80
  81 /*
  82  * Gamepad configuration data.  Other 9-pin digital joystick devices
  83  * may work with the multiport, so this may not be an exhaustive list!
  84  * Commodore 64 joystick remains untested.
  85  */
  86
  87 #define GRIP_INIT_DELAY         2000          /*  2 ms */
  88
  89 #define GRIP_MODE_NONE          0
  90 #define GRIP_MODE_RESET         1
  91 #define GRIP_MODE_GP            2
  92 #define GRIP_MODE_C64           3
  93
  94 static const int grip_btn_gp[]  = { BTN_TR, BTN_TL, BTN_A, BTN_B, BTN_C, BTN_X, BTN_Y, BTN_Z, -1 };
  95 static const int grip_btn_c64[] = { BTN_JOYSTICK, -1 };
  96
  97 static const int grip_abs_gp[]  = { ABS_X, ABS_Y, -1 };
  98 static const int grip_abs_c64[] = { ABS_X, ABS_Y, -1 };
  99
 100 static const int *grip_abs[] = { NULL, NULL, grip_abs_gp, grip_abs_c64 };
 101 static const int *grip_btn[] = { NULL, NULL, grip_btn_gp, grip_btn_c64 };
 102
 103 static const char *grip_name[] = { NULL, NULL, "Gravis Grip Pad", "Commodore 64 Joystick" };
 104
 105 static const int init_seq[] = {
 106         1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1,
 107         1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1,
 108         1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1,
 109         0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1 };
 110
 111 /* Maps multiport directional values to X,Y axis values (each axis encoded in 3 bits) */
 112
 113 static const int axis_map[] = { 5, 9, 1, 5, 6, 10, 2, 6, 4, 8, 0, 4, 5, 9, 1, 5 };
 114
 115 static int register_slot(int i, struct grip_mp *grip);
 116
 117 /*
 118  * Returns whether an odd or even number of bits are on in pkt.
 119  */
 120
 121 static int bit_parity(u32 pkt)
 122 {
 123         int x = pkt ^ (pkt >> 16);
 124         x ^= x >> 8;
 125         x ^= x >> 4;
 126         x ^= x >> 2;
 127         x ^= x >> 1;
 128         return x & 1;
 129 }
 130
 131 /*
 132  * Poll gameport; return true if all bits set in 'onbits' are on and
 133  * all bits set in 'offbits' are off.
 134  */
 135
 136 static inline int poll_until(u8 onbits, u8 offbits, int u_sec, struct gameport* gp, u8 *data)
 137 {
 138         int i, nloops;
 139
 140         nloops = gameport_time(gp, u_sec);
 141         for (i = 0; i < nloops; i++) {
 142                 *data = gameport_read(gp);
 143                 if ((*data & onbits) == onbits &&
 144                     (~(*data) & offbits) == offbits)
 145                         return 1;
 146         }
 147         dbg("gameport timed out after %d microseconds.\n", u_sec);
 148         return 0;
 149 }
 150
 151 /*
 152  * Gets a 28-bit packet from the multiport.
 153  *
 154  * After getting a packet successfully, commands encoded by sendcode may
 155  * be sent to the multiport.
 156  *
 157  * The multiport clock value is reflected in gameport bit B4.
 158  *
 159  * Returns a packet status code indicating whether packet is valid, the transfer
 160  * mode, and any error conditions.
 161  *
 162  * sendflags:      current I/O status
 163  * sendcode:   data to send to the multiport if sendflags is nonzero
 164  */
 165
 166 static int mp_io(struct gameport* gameport, int sendflags, int sendcode, u32 *packet)
 167 {
 168         u8  raw_data;            /* raw data from gameport */
 169         u8  data_mask;           /* packet data bits from raw_data */
 170         u32 pkt;                 /* packet temporary storage */
 171         int bits_per_read;       /* num packet bits per gameport read */
 172         int portvals = 0;        /* used for port value sanity check */
 173         int i;
 174
 175         /* Gameport bits B0, B4, B5 should first be off, then B4 should come on. */
 176
 177         *packet = 0;
 178         raw_data = gameport_read(gameport);
 179         if (raw_data & 1)
 180                 return IO_RETRY;
 181
 182         for (i = 0; i < 64; i++) {
 183                 raw_data = gameport_read(gameport);
 184                 portvals |= 1 << ((raw_data >> 4) & 3); /* Demux B4, B5 */
 185         }
 186
 187         if (portvals == 1) {                            /* B4, B5 off */
 188                 raw_data = gameport_read(gameport);
 189                 portvals = raw_data & 0xf0;
 190
 191                 if (raw_data & 0x31)
 192                         return IO_RESET;
 193                 gameport_trigger(gameport);
 194
 195                 if (!poll_until(0x10, 0, 308, gameport, &raw_data))
 196                         return IO_RESET;
 197         } else
 198                 return IO_RETRY;
 199
 200         /* Determine packet transfer mode and prepare for packet construction. */
 201
 202         if (raw_data & 0x20) {                 /* 3 data bits/read */
 203                 portvals |= raw_data >> 4;     /* Compare B4-B7 before & after trigger */
 204
 205                 if (portvals != 0xb)
 206                         return 0;
 207                 data_mask = 7;
 208                 bits_per_read = 3;
 209                 pkt = (PACKET_FULL | PACKET_IO_FAST) >> 28;
 210         } else {                                 /* 1 data bit/read */
 211                 data_mask = 1;
 212                 bits_per_read = 1;
 213                 pkt = (PACKET_FULL | PACKET_IO_SLOW) >> 28;
 214         }
 215
 216         /* Construct a packet.  Final data bits must be zero. */
 217
 218         while (1) {
 219                 if (!poll_until(0, 0x10, 77, gameport, &raw_data))
 220                         return IO_RESET;
 221                 raw_data = (raw_data >> 5) & data_mask;
 222
 223                 if (pkt & PACKET_FULL)
 224                         break;
 225                 pkt = (pkt << bits_per_read) | raw_data;
 226
 227                 if (!poll_until(0x10, 0, 77, gameport, &raw_data))
 228                         return IO_RESET;
 229         }
 230
 231         if (raw_data)
 232                 return IO_RESET;
 233
 234         /* If 3 bits/read used, drop from 30 bits to 28. */
 235
 236         if (bits_per_read == 3) {
 237                 pkt = (pkt & 0xffff0000) | ((pkt << 1) & 0xffff);
 238                 pkt = (pkt >> 2) | 0xf0000000;
 239         }
 240
 241         if (bit_parity(pkt) == 1)
 242                 return IO_RESET;
 243
 244         /* Acknowledge packet receipt */
 245
 246         if (!poll_until(0x30, 0, 77, gameport, &raw_data))
 247                 return IO_RESET;
 248
 249         raw_data = gameport_read(gameport);
 250
 251         if (raw_data & 1)
 252                 return IO_RESET;
 253
 254         gameport_trigger(gameport);
 255
 256         if (!poll_until(0, 0x20, 77, gameport, &raw_data))
 257                 return IO_RESET;
 258
 259         /* Return if we just wanted the packet or multiport wants to send more */
 260
 261         *packet = pkt;
 262         if ((sendflags == 0) || ((sendflags & IO_RETRY) && !(pkt & PACKET_MP_DONE)))
 263                 return IO_GOT_PACKET;
 264
 265         if (pkt & PACKET_MP_MORE)
 266                 return IO_GOT_PACKET | IO_RETRY;
 267
 268         /* Multiport is done sending packets and is ready to receive data */
 269
 270         if (!poll_until(0x20, 0, 77, gameport, &raw_data))
 271                 return IO_GOT_PACKET | IO_RESET;
 272
 273         raw_data = gameport_read(gameport);
 274         if (raw_data & 1)
 275                 return IO_GOT_PACKET | IO_RESET;
 276
 277         /* Trigger gameport based on bits in sendcode */
 278
 279         gameport_trigger(gameport);
 280         do {
 281                 if (!poll_until(0x20, 0x10, 116, gameport, &raw_data))
 282                         return IO_GOT_PACKET | IO_RESET;
 283
 284                 if (!poll_until(0x30, 0, 193, gameport, &raw_data))
 285                         return IO_GOT_PACKET | IO_RESET;
 286
 287                 if (raw_data & 1)
 288                         return IO_GOT_PACKET | IO_RESET;
 289
 290                 if (sendcode & 1)
 291                         gameport_trigger(gameport);
 292
 293                 sendcode >>= 1;
 294         } while (sendcode);
 295
 296         return IO_GOT_PACKET | IO_MODE_FAST;
 297 }
 298
 299 /*
 300  * Disables and restores interrupts for mp_io(), which does the actual I/O.
 301  */
 302
 303 static int multiport_io(struct gameport* gameport, int sendflags, int sendcode, u32 *packet)
 304 {
 305         int status;
 306         unsigned long flags;
 307
 308         local_irq_save(flags);
 309         status = mp_io(gameport, sendflags, sendcode, packet);
 310         local_irq_restore(flags);
 311
 312         return status;
 313 }
 314
 315 /*
 316  * Puts multiport into digital mode.  Multiport LED turns green.
 317  *
 318  * Returns true if a valid digital packet was received, false otherwise.
 319  */
 320
 321 static int dig_mode_start(struct gameport *gameport, u32 *packet)
 322 {
 323         int i, seq_len = sizeof(init_seq)/sizeof(int);
 324         int flags, tries = 0, bads = 0;
 325
 326         for (i = 0; i < seq_len; i++) {     /* Send magic sequence */
 327                 if (init_seq[i])
 328                         gameport_trigger(gameport);
 329                 udelay(GRIP_INIT_DELAY);
 330         }
 331
 332         for (i = 0; i < 16; i++)            /* Wait for multiport to settle */
 333                 udelay(GRIP_INIT_DELAY);
 334
 335         while (tries < 64 && bads < 8) {    /* Reset multiport and try getting a packet */
 336
 337                 flags = multiport_io(gameport, IO_RESET, 0x27, packet);
 338
 339                 if (flags & IO_MODE_FAST)
 340                         return 1;
 341
 342                 if (flags & IO_RETRY)
 343                         tries++;
 344                 else
 345                         bads++;
 346         }
 347         return 0;
 348 }
 349
 350 /*
 351  * Packet structure: B0-B15   => gamepad state
 352  *                   B16-B20  => gamepad device type
 353  *                   B21-B24  => multiport slot index (1-4)
 354  *
 355  * Known device types: 0x1f (grip pad), 0x0 (no device).  Others may exist.
 356  *
 357  * Returns the packet status.
 358  */
 359
 360 static int get_and_decode_packet(struct grip_mp *grip, int flags)
 361 {
 362         struct grip_port *port;
 363         u32 packet;
 364         int joytype = 0;
 365         int slot;
 366
 367         /* Get a packet and check for validity */
 368
 369         flags &= IO_RESET | IO_RETRY;
 370         flags = multiport_io(grip->gameport, flags, 0, &packet);
 371         grip->reads++;
 372
 373         if (packet & PACKET_MP_DONE)
 374                 flags |= IO_DONE;
 375
 376         if (flags && !(flags & IO_GOT_PACKET)) {
 377                 grip->bads++;
 378                 return flags;
 379         }
 380
 381         /* Ignore non-gamepad packets, e.g. multiport hardware version */
 382
 383         slot = ((packet >> 21) & 0xf) - 1;
 384         if ((slot < 0) || (slot > 3))
 385                 return flags;
 386
 387         port = grip->port[slot];
 388
 389         /*
 390          * Handle "reset" packets, which occur at startup, and when gamepads
 391          * are removed or plugged in.  May contain configuration of a new gamepad.
 392          */
 393
 394         joytype = (packet >> 16) & 0x1f;
 395         if (!joytype) {
 396
 397                 if (port->registered) {
 398                         printk(KERN_INFO "grip_mp: removing %s, slot %d\n",
 399                                grip_name[port->mode], slot);
 400                         input_unregister_device(port->dev);
 401                         port->registered = 0;
 402                 }
 403                 dbg("Reset: grip multiport slot %d\n", slot);
 404                 port->mode = GRIP_MODE_RESET;
 405                 flags |= IO_SLOT_CHANGE;
 406                 return flags;
 407         }
 408
 409         /* Interpret a grip pad packet */
 410
 411         if (joytype == 0x1f) {
 412
 413                 int dir = (packet >> 8) & 0xf;          /* eight way directional value */
 414                 port->buttons = (~packet) & 0xff;
 415                 port->yaxes = ((axis_map[dir] >> 2) & 3) - 1;
 416                 port->xaxes = (axis_map[dir] & 3) - 1;
 417                 port->dirty = 1;
 418
 419                 if (port->mode == GRIP_MODE_RESET)
 420                         flags |= IO_SLOT_CHANGE;
 421
 422                 port->mode = GRIP_MODE_GP;
 423
 424                 if (!port->registered) {
 425                         dbg("New Grip pad in multiport slot %d.\n", slot);
 426                         if (register_slot(slot, grip)) {
 427                                 port->mode = GRIP_MODE_RESET;
 428                                 port->dirty = 0;
 429                         }
 430                 }
 431                 return flags;
 432         }
 433
 434         /* Handle non-grip device codes.  For now, just print diagnostics. */
 435
 436         {
 437                 static int strange_code = 0;
 438                 if (strange_code != joytype) {
 439                         printk(KERN_INFO "Possible non-grip pad/joystick detected.\n");
 440                         printk(KERN_INFO "Got joy type 0x%x and packet 0x%x.\n", joytype, packet);
 441                         strange_code = joytype;
 442                 }
 443         }
 444         return flags;
 445 }
 446
 447 /*
 448  * Returns true if all multiport slot states appear valid.
 449  */
 450
 451 static int slots_valid(struct grip_mp *grip)
 452 {
 453         int flags, slot, invalid = 0, active = 0;
 454
 455         flags = get_and_decode_packet(grip, 0);
 456         if (!(flags & IO_GOT_PACKET))
 457                 return 0;
 458
 459         for (slot = 0; slot < 4; slot++) {
 460                 if (grip->port[slot]->mode == GRIP_MODE_RESET)
 461                         invalid = 1;
 462                 if (grip->port[slot]->mode != GRIP_MODE_NONE)
 463                         active = 1;
 464         }
 465
 466         /* Return true if no active slot but multiport sent all its data */
 467         if (!active)
 468                 return (flags & IO_DONE) ? 1 : 0;
 469
 470         /* Return false if invalid device code received */
 471         return invalid ? 0 : 1;
 472 }
 473
 474 /*
 475  * Returns whether the multiport was placed into digital mode and
 476  * able to communicate its state successfully.
 477  */
 478
 479 static int multiport_init(struct grip_mp *grip)
 480 {
 481         int dig_mode, initialized = 0, tries = 0;
 482         u32 packet;
 483
 484         dig_mode = dig_mode_start(grip->gameport, &packet);
 485         while (!dig_mode && tries < 4) {
 486                 dig_mode = dig_mode_start(grip->gameport, &packet);
 487                 tries++;
 488         }
 489
 490         if (dig_mode)
 491                 dbg("multiport_init(): digital mode activated.\n");
 492         else {
 493                 dbg("multiport_init(): unable to activate digital mode.\n");
 494                 return 0;
 495         }
 496
 497         /* Get packets, store multiport state, and check state's validity */
 498         for (tries = 0; tries < 4096; tries++) {
 499                 if (slots_valid(grip)) {
 500                         initialized = 1;
 501                         break;
 502                 }
 503         }
 504         dbg("multiport_init(): initialized == %d\n", initialized);
 505         return initialized;
 506 }
 507
 508 /*
 509  * Reports joystick state to the linux input layer.
 510  */
 511
 512 static void report_slot(struct grip_mp *grip, int slot)
 513 {
 514         struct grip_port *port = grip->port[slot];
 515         int i;
 516
 517         /* Store button states with linux input driver */
 518
 519         for (i = 0; i < 8; i++)
 520                 input_report_key(port->dev, grip_btn_gp[i], (port->buttons >> i) & 1);
 521
 522         /* Store axis states with linux driver */
 523
 524         input_report_abs(port->dev, ABS_X, port->xaxes);
 525         input_report_abs(port->dev, ABS_Y, port->yaxes);
 526
 527         /* Tell the receiver of the events to process them */
 528
 529         input_sync(port->dev);
 530
 531         port->dirty = 0;
 532 }
 533
 534 /*
 535  * Get the multiport state.
 536  */
 537
 538 static void grip_poll(struct gameport *gameport)
 539 {
 540         struct grip_mp *grip = gameport_get_drvdata(gameport);
 541         int i, npkts, flags;
 542
 543         for (npkts = 0; npkts < 4; npkts++) {
 544                 flags = IO_RETRY;
 545                 for (i = 0; i < 32; i++) {
 546                         flags = get_and_decode_packet(grip, flags);
 547                         if ((flags & IO_GOT_PACKET) || !(flags & IO_RETRY))
 548                                 break;
 549                 }
 550                 if (flags & IO_DONE)
 551                         break;
 552         }
 553
 554         for (i = 0; i < 4; i++)
 555                 if (grip->port[i]->dirty)
 556                         report_slot(grip, i);
 557 }
 558
 559 /*
 560  * Called when a joystick device file is opened
 561  */
 562
 563 static int grip_open(struct input_dev *dev)
 564 {
 565         struct grip_mp *grip = dev->private;
 566
 567         gameport_start_polling(grip->gameport);
 568         return 0;
 569 }
 570
 571 /*
 572  * Called when a joystick device file is closed
 573  */
 574
 575 static void grip_close(struct input_dev *dev)
 576 {
 577         struct grip_mp *grip = dev->private;
 578
 579         gameport_start_polling(grip->gameport);
 580 }
 581
 582 /*
 583  * Tell the linux input layer about a newly plugged-in gamepad.
 584  */
 585
 586 static int register_slot(int slot, struct grip_mp *grip)
 587 {
 588         struct grip_port *port = grip->port[slot];
 589         struct input_dev *input_dev;
 590         int j, t;
 591         int err;
 592
 593         port->dev = input_dev = input_allocate_device();
 594         if (!input_dev)
 595                 return -ENOMEM;
 596
 597         input_dev->name = grip_name[port->mode];
 598         input_dev->id.bustype = BUS_GAMEPORT;
 599         input_dev->id.vendor = GAMEPORT_ID_VENDOR_GRAVIS;
 600         input_dev->id.product = 0x0100 + port->mode;
 601         input_dev->id.version = 0x0100;
 602         input_dev->cdev.dev = &grip->gameport->dev;
 603         input_dev->private = grip;
 604
 605         input_dev->open = grip_open;
 606         input_dev->close = grip_close;
 607
 608         input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
 609
 610         for (j = 0; (t = grip_abs[port->mode][j]) >= 0; j++)
 611                 input_set_abs_params(input_dev, t, -1, 1, 0, 0);
 612
 613         for (j = 0; (t = grip_btn[port->mode][j]) >= 0; j++)
 614                 if (t > 0)
 615                         set_bit(t, input_dev->keybit);
 616
 617         err = input_register_device(port->dev);
 618         if (err) {
 619                 input_free_device(port->dev);
 620                 return err;
 621         }
 622
 623         port->registered = 1;
 624
 625         if (port->dirty)                    /* report initial state, if any */
 626                 report_slot(grip, slot);
 627
 628         return 0;
 629 }
 630
 631 static int grip_connect(struct gameport *gameport, struct gameport_driver *drv)
 632 {
 633         struct grip_mp *grip;
 634         int err;
 635
 636         if (!(grip = kzalloc(sizeof(struct grip_mp), GFP_KERNEL)))
 637                 return -ENOMEM;
 638
 639         grip->gameport = gameport;
 640
 641         gameport_set_drvdata(gameport, grip);
 642
 643         err = gameport_open(gameport, drv, GAMEPORT_MODE_RAW);
 644         if (err)
 645                 goto fail1;
 646
 647         gameport_set_poll_handler(gameport, grip_poll);
 648         gameport_set_poll_interval(gameport, 20);
 649
 650         if (!multiport_init(grip)) {
 651                 err = -ENODEV;
 652                 goto fail2;
 653         }
 654
 655         if (!grip->port[0]->mode && !grip->port[1]->mode && !grip->port[2]->mode && !grip->port[3]->mode) {
 656                 /* nothing plugged in */
 657                 err = -ENODEV;
 658                 goto fail2;
 659         }
 660
 661         return 0;
 662
 663 fail2:  gameport_close(gameport);
 664 fail1:  gameport_set_drvdata(gameport, NULL);
 665         kfree(grip);
 666         return err;
 667 }
 668
 669 static void grip_disconnect(struct gameport *gameport)
 670 {
 671         struct grip_mp *grip = gameport_get_drvdata(gameport);
 672         int i;
 673
 674         for (i = 0; i < 4; i++)
 675                 if (grip->port[i]->registered)
 676                         input_unregister_device(grip->port[i]->dev);
 677         gameport_close(gameport);
 678         gameport_set_drvdata(gameport, NULL);
 679         kfree(grip);
 680 }
 681
 682 static struct gameport_driver grip_drv = {
 683         .driver         = {
 684                 .name   = "grip_mp",
 685         },
 686         .description    = DRIVER_DESC,
 687         .connect        = grip_connect,
 688         .disconnect     = grip_disconnect,
 689 };
 690
 691 static int __init grip_init(void)
 692 {
 693         gameport_register_driver(&grip_drv);
 694         return 0;
 695 }
 696
 697 static void __exit grip_exit(void)
 698 {
 699         gameport_unregister_driver(&grip_drv);
 700 }
 701
 702 module_init(grip_init);
 703 module_exit(grip_exit);