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; 324 int flags, tries = 0, bads = 0; 325 326 for (i = 0; i < ARRAY_SIZE(init_seq); 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 = input_get_drvdata(dev); 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 = input_get_drvdata(dev); 578 579 gameport_stop_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->dev.parent = &grip->gameport->dev; 603 604 input_set_drvdata(input_dev, grip); 605 606 input_dev->open = grip_open; 607 input_dev->close = grip_close; 608 609 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 610 611 for (j = 0; (t = grip_abs[port->mode][j]) >= 0; j++) 612 input_set_abs_params(input_dev, t, -1, 1, 0, 0); 613 614 for (j = 0; (t = grip_btn[port->mode][j]) >= 0; j++) 615 if (t > 0) 616 set_bit(t, input_dev->keybit); 617 618 err = input_register_device(port->dev); 619 if (err) { 620 input_free_device(port->dev); 621 return err; 622 } 623 624 port->registered = 1; 625 626 if (port->dirty) /* report initial state, if any */ 627 report_slot(grip, slot); 628 629 return 0; 630 } 631 632 static int grip_connect(struct gameport *gameport, struct gameport_driver *drv) 633 { 634 struct grip_mp *grip; 635 int err; 636 637 if (!(grip = kzalloc(sizeof(struct grip_mp), GFP_KERNEL))) 638 return -ENOMEM; 639 640 grip->gameport = gameport; 641 642 gameport_set_drvdata(gameport, grip); 643 644 err = gameport_open(gameport, drv, GAMEPORT_MODE_RAW); 645 if (err) 646 goto fail1; 647 648 gameport_set_poll_handler(gameport, grip_poll); 649 gameport_set_poll_interval(gameport, 20); 650 651 if (!multiport_init(grip)) { 652 err = -ENODEV; 653 goto fail2; 654 } 655 656 if (!grip->port[0]->mode && !grip->port[1]->mode && !grip->port[2]->mode && !grip->port[3]->mode) { 657 /* nothing plugged in */ 658 err = -ENODEV; 659 goto fail2; 660 } 661 662 return 0; 663 664 fail2: gameport_close(gameport); 665 fail1: gameport_set_drvdata(gameport, NULL); 666 kfree(grip); 667 return err; 668 } 669 670 static void grip_disconnect(struct gameport *gameport) 671 { 672 struct grip_mp *grip = gameport_get_drvdata(gameport); 673 int i; 674 675 for (i = 0; i < 4; i++) 676 if (grip->port[i]->registered) 677 input_unregister_device(grip->port[i]->dev); 678 gameport_close(gameport); 679 gameport_set_drvdata(gameport, NULL); 680 kfree(grip); 681 } 682 683 static struct gameport_driver grip_drv = { 684 .driver = { 685 .name = "grip_mp", 686 }, 687 .description = DRIVER_DESC, 688 .connect = grip_connect, 689 .disconnect = grip_disconnect, 690 }; 691 692 static int __init grip_init(void) 693 { 694 gameport_register_driver(&grip_drv); 695 return 0; 696 } 697 698 static void __exit grip_exit(void) 699 { 700 gameport_unregister_driver(&grip_drv); 701 } 702 703 module_init(grip_init); 704 module_exit(grip_exit); 705