1 /* ppa.c -- low level driver for the IOMEGA PPA3 2 * parallel port SCSI host adapter. 3 * 4 * (The PPA3 is the embedded controller in the ZIP drive.) 5 * 6 * (c) 1995,1996 Grant R. Guenther, grant@torque.net, 7 * under the terms of the GNU General Public License. 8 * 9 */ 10 11 #include <linux/init.h> 12 #include <linux/kernel.h> 13 #include <linux/module.h> 14 #include <linux/blkdev.h> 15 #include <linux/parport.h> 16 #include <linux/workqueue.h> 17 #include <linux/delay.h> 18 #include <linux/jiffies.h> 19 #include <asm/io.h> 20 21 #include <scsi/scsi.h> 22 #include <scsi/scsi_cmnd.h> 23 #include <scsi/scsi_device.h> 24 #include <scsi/scsi_host.h> 25 26 27 static void ppa_reset_pulse(unsigned int base); 28 29 typedef struct { 30 struct pardevice *dev; /* Parport device entry */ 31 int base; /* Actual port address */ 32 int mode; /* Transfer mode */ 33 struct scsi_cmnd *cur_cmd; /* Current queued command */ 34 struct delayed_work ppa_tq; /* Polling interrupt stuff */ 35 unsigned long jstart; /* Jiffies at start */ 36 unsigned long recon_tmo; /* How many usecs to wait for reconnection (6th bit) */ 37 unsigned int failed:1; /* Failure flag */ 38 unsigned wanted:1; /* Parport sharing busy flag */ 39 wait_queue_head_t *waiting; 40 struct Scsi_Host *host; 41 struct list_head list; 42 } ppa_struct; 43 44 #include "ppa.h" 45 46 static inline ppa_struct *ppa_dev(struct Scsi_Host *host) 47 { 48 return *(ppa_struct **)&host->hostdata; 49 } 50 51 static DEFINE_SPINLOCK(arbitration_lock); 52 53 static void got_it(ppa_struct *dev) 54 { 55 dev->base = dev->dev->port->base; 56 if (dev->cur_cmd) 57 dev->cur_cmd->SCp.phase = 1; 58 else 59 wake_up(dev->waiting); 60 } 61 62 static void ppa_wakeup(void *ref) 63 { 64 ppa_struct *dev = (ppa_struct *) ref; 65 unsigned long flags; 66 67 spin_lock_irqsave(&arbitration_lock, flags); 68 if (dev->wanted) { 69 parport_claim(dev->dev); 70 got_it(dev); 71 dev->wanted = 0; 72 } 73 spin_unlock_irqrestore(&arbitration_lock, flags); 74 return; 75 } 76 77 static int ppa_pb_claim(ppa_struct *dev) 78 { 79 unsigned long flags; 80 int res = 1; 81 spin_lock_irqsave(&arbitration_lock, flags); 82 if (parport_claim(dev->dev) == 0) { 83 got_it(dev); 84 res = 0; 85 } 86 dev->wanted = res; 87 spin_unlock_irqrestore(&arbitration_lock, flags); 88 return res; 89 } 90 91 static void ppa_pb_dismiss(ppa_struct *dev) 92 { 93 unsigned long flags; 94 int wanted; 95 spin_lock_irqsave(&arbitration_lock, flags); 96 wanted = dev->wanted; 97 dev->wanted = 0; 98 spin_unlock_irqrestore(&arbitration_lock, flags); 99 if (!wanted) 100 parport_release(dev->dev); 101 } 102 103 static inline void ppa_pb_release(ppa_struct *dev) 104 { 105 parport_release(dev->dev); 106 } 107 108 /* 109 * Start of Chipset kludges 110 */ 111 112 /* This is to give the ppa driver a way to modify the timings (and other 113 * parameters) by writing to the /proc/scsi/ppa/0 file. 114 * Very simple method really... (To simple, no error checking :( ) 115 * Reason: Kernel hackers HATE having to unload and reload modules for 116 * testing... 117 * Also gives a method to use a script to obtain optimum timings (TODO) 118 */ 119 120 static inline int ppa_proc_write(ppa_struct *dev, char *buffer, int length) 121 { 122 unsigned long x; 123 124 if ((length > 5) && (strncmp(buffer, "mode=", 5) == 0)) { 125 x = simple_strtoul(buffer + 5, NULL, 0); 126 dev->mode = x; 127 return length; 128 } 129 if ((length > 10) && (strncmp(buffer, "recon_tmo=", 10) == 0)) { 130 x = simple_strtoul(buffer + 10, NULL, 0); 131 dev->recon_tmo = x; 132 printk("ppa: recon_tmo set to %ld\n", x); 133 return length; 134 } 135 printk("ppa /proc: invalid variable\n"); 136 return (-EINVAL); 137 } 138 139 static int ppa_proc_info(struct Scsi_Host *host, char *buffer, char **start, off_t offset, int length, int inout) 140 { 141 int len = 0; 142 ppa_struct *dev = ppa_dev(host); 143 144 if (inout) 145 return ppa_proc_write(dev, buffer, length); 146 147 len += sprintf(buffer + len, "Version : %s\n", PPA_VERSION); 148 len += 149 sprintf(buffer + len, "Parport : %s\n", 150 dev->dev->port->name); 151 len += 152 sprintf(buffer + len, "Mode : %s\n", 153 PPA_MODE_STRING[dev->mode]); 154 #if PPA_DEBUG > 0 155 len += 156 sprintf(buffer + len, "recon_tmo : %lu\n", dev->recon_tmo); 157 #endif 158 159 /* Request for beyond end of buffer */ 160 if (offset > length) 161 return 0; 162 163 *start = buffer + offset; 164 len -= offset; 165 if (len > length) 166 len = length; 167 return len; 168 } 169 170 static int device_check(ppa_struct *dev); 171 172 #if PPA_DEBUG > 0 173 #define ppa_fail(x,y) printk("ppa: ppa_fail(%i) from %s at line %d\n",\ 174 y, __FUNCTION__, __LINE__); ppa_fail_func(x,y); 175 static inline void ppa_fail_func(ppa_struct *dev, int error_code) 176 #else 177 static inline void ppa_fail(ppa_struct *dev, int error_code) 178 #endif 179 { 180 /* If we fail a device then we trash status / message bytes */ 181 if (dev->cur_cmd) { 182 dev->cur_cmd->result = error_code << 16; 183 dev->failed = 1; 184 } 185 } 186 187 /* 188 * Wait for the high bit to be set. 189 * 190 * In principle, this could be tied to an interrupt, but the adapter 191 * doesn't appear to be designed to support interrupts. We spin on 192 * the 0x80 ready bit. 193 */ 194 static unsigned char ppa_wait(ppa_struct *dev) 195 { 196 int k; 197 unsigned short ppb = dev->base; 198 unsigned char r; 199 200 k = PPA_SPIN_TMO; 201 /* Wait for bit 6 and 7 - PJC */ 202 for (r = r_str(ppb); ((r & 0xc0) != 0xc0) && (k); k--) { 203 udelay(1); 204 r = r_str(ppb); 205 } 206 207 /* 208 * return some status information. 209 * Semantics: 0xc0 = ZIP wants more data 210 * 0xd0 = ZIP wants to send more data 211 * 0xe0 = ZIP is expecting SCSI command data 212 * 0xf0 = end of transfer, ZIP is sending status 213 */ 214 if (k) 215 return (r & 0xf0); 216 217 /* Counter expired - Time out occurred */ 218 ppa_fail(dev, DID_TIME_OUT); 219 printk("ppa timeout in ppa_wait\n"); 220 return 0; /* command timed out */ 221 } 222 223 /* 224 * Clear EPP Timeout Bit 225 */ 226 static inline void epp_reset(unsigned short ppb) 227 { 228 int i; 229 230 i = r_str(ppb); 231 w_str(ppb, i); 232 w_str(ppb, i & 0xfe); 233 } 234 235 /* 236 * Wait for empty ECP fifo (if we are in ECP fifo mode only) 237 */ 238 static inline void ecp_sync(ppa_struct *dev) 239 { 240 int i, ppb_hi = dev->dev->port->base_hi; 241 242 if (ppb_hi == 0) 243 return; 244 245 if ((r_ecr(ppb_hi) & 0xe0) == 0x60) { /* mode 011 == ECP fifo mode */ 246 for (i = 0; i < 100; i++) { 247 if (r_ecr(ppb_hi) & 0x01) 248 return; 249 udelay(5); 250 } 251 printk("ppa: ECP sync failed as data still present in FIFO.\n"); 252 } 253 } 254 255 static int ppa_byte_out(unsigned short base, const char *buffer, int len) 256 { 257 int i; 258 259 for (i = len; i; i--) { 260 w_dtr(base, *buffer++); 261 w_ctr(base, 0xe); 262 w_ctr(base, 0xc); 263 } 264 return 1; /* All went well - we hope! */ 265 } 266 267 static int ppa_byte_in(unsigned short base, char *buffer, int len) 268 { 269 int i; 270 271 for (i = len; i; i--) { 272 *buffer++ = r_dtr(base); 273 w_ctr(base, 0x27); 274 w_ctr(base, 0x25); 275 } 276 return 1; /* All went well - we hope! */ 277 } 278 279 static int ppa_nibble_in(unsigned short base, char *buffer, int len) 280 { 281 for (; len; len--) { 282 unsigned char h; 283 284 w_ctr(base, 0x4); 285 h = r_str(base) & 0xf0; 286 w_ctr(base, 0x6); 287 *buffer++ = h | ((r_str(base) & 0xf0) >> 4); 288 } 289 return 1; /* All went well - we hope! */ 290 } 291 292 static int ppa_out(ppa_struct *dev, char *buffer, int len) 293 { 294 int r; 295 unsigned short ppb = dev->base; 296 297 r = ppa_wait(dev); 298 299 if ((r & 0x50) != 0x40) { 300 ppa_fail(dev, DID_ERROR); 301 return 0; 302 } 303 switch (dev->mode) { 304 case PPA_NIBBLE: 305 case PPA_PS2: 306 /* 8 bit output, with a loop */ 307 r = ppa_byte_out(ppb, buffer, len); 308 break; 309 310 case PPA_EPP_32: 311 case PPA_EPP_16: 312 case PPA_EPP_8: 313 epp_reset(ppb); 314 w_ctr(ppb, 0x4); 315 #ifdef CONFIG_SCSI_IZIP_EPP16 316 if (!(((long) buffer | len) & 0x01)) 317 outsw(ppb + 4, buffer, len >> 1); 318 #else 319 if (!(((long) buffer | len) & 0x03)) 320 outsl(ppb + 4, buffer, len >> 2); 321 #endif 322 else 323 outsb(ppb + 4, buffer, len); 324 w_ctr(ppb, 0xc); 325 r = !(r_str(ppb) & 0x01); 326 w_ctr(ppb, 0xc); 327 ecp_sync(dev); 328 break; 329 330 default: 331 printk("PPA: bug in ppa_out()\n"); 332 r = 0; 333 } 334 return r; 335 } 336 337 static int ppa_in(ppa_struct *dev, char *buffer, int len) 338 { 339 int r; 340 unsigned short ppb = dev->base; 341 342 r = ppa_wait(dev); 343 344 if ((r & 0x50) != 0x50) { 345 ppa_fail(dev, DID_ERROR); 346 return 0; 347 } 348 switch (dev->mode) { 349 case PPA_NIBBLE: 350 /* 4 bit input, with a loop */ 351 r = ppa_nibble_in(ppb, buffer, len); 352 w_ctr(ppb, 0xc); 353 break; 354 355 case PPA_PS2: 356 /* 8 bit input, with a loop */ 357 w_ctr(ppb, 0x25); 358 r = ppa_byte_in(ppb, buffer, len); 359 w_ctr(ppb, 0x4); 360 w_ctr(ppb, 0xc); 361 break; 362 363 case PPA_EPP_32: 364 case PPA_EPP_16: 365 case PPA_EPP_8: 366 epp_reset(ppb); 367 w_ctr(ppb, 0x24); 368 #ifdef CONFIG_SCSI_IZIP_EPP16 369 if (!(((long) buffer | len) & 0x01)) 370 insw(ppb + 4, buffer, len >> 1); 371 #else 372 if (!(((long) buffer | len) & 0x03)) 373 insl(ppb + 4, buffer, len >> 2); 374 #endif 375 else 376 insb(ppb + 4, buffer, len); 377 w_ctr(ppb, 0x2c); 378 r = !(r_str(ppb) & 0x01); 379 w_ctr(ppb, 0x2c); 380 ecp_sync(dev); 381 break; 382 383 default: 384 printk("PPA: bug in ppa_ins()\n"); 385 r = 0; 386 break; 387 } 388 return r; 389 } 390 391 /* end of ppa_io.h */ 392 static inline void ppa_d_pulse(unsigned short ppb, unsigned char b) 393 { 394 w_dtr(ppb, b); 395 w_ctr(ppb, 0xc); 396 w_ctr(ppb, 0xe); 397 w_ctr(ppb, 0xc); 398 w_ctr(ppb, 0x4); 399 w_ctr(ppb, 0xc); 400 } 401 402 static void ppa_disconnect(ppa_struct *dev) 403 { 404 unsigned short ppb = dev->base; 405 406 ppa_d_pulse(ppb, 0); 407 ppa_d_pulse(ppb, 0x3c); 408 ppa_d_pulse(ppb, 0x20); 409 ppa_d_pulse(ppb, 0xf); 410 } 411 412 static inline void ppa_c_pulse(unsigned short ppb, unsigned char b) 413 { 414 w_dtr(ppb, b); 415 w_ctr(ppb, 0x4); 416 w_ctr(ppb, 0x6); 417 w_ctr(ppb, 0x4); 418 w_ctr(ppb, 0xc); 419 } 420 421 static inline void ppa_connect(ppa_struct *dev, int flag) 422 { 423 unsigned short ppb = dev->base; 424 425 ppa_c_pulse(ppb, 0); 426 ppa_c_pulse(ppb, 0x3c); 427 ppa_c_pulse(ppb, 0x20); 428 if ((flag == CONNECT_EPP_MAYBE) && IN_EPP_MODE(dev->mode)) 429 ppa_c_pulse(ppb, 0xcf); 430 else 431 ppa_c_pulse(ppb, 0x8f); 432 } 433 434 static int ppa_select(ppa_struct *dev, int target) 435 { 436 int k; 437 unsigned short ppb = dev->base; 438 439 /* 440 * Bit 6 (0x40) is the device selected bit. 441 * First we must wait till the current device goes off line... 442 */ 443 k = PPA_SELECT_TMO; 444 do { 445 k--; 446 udelay(1); 447 } while ((r_str(ppb) & 0x40) && (k)); 448 if (!k) 449 return 0; 450 451 w_dtr(ppb, (1 << target)); 452 w_ctr(ppb, 0xe); 453 w_ctr(ppb, 0xc); 454 w_dtr(ppb, 0x80); /* This is NOT the initator */ 455 w_ctr(ppb, 0x8); 456 457 k = PPA_SELECT_TMO; 458 do { 459 k--; 460 udelay(1); 461 } 462 while (!(r_str(ppb) & 0x40) && (k)); 463 if (!k) 464 return 0; 465 466 return 1; 467 } 468 469 /* 470 * This is based on a trace of what the Iomega DOS 'guest' driver does. 471 * I've tried several different kinds of parallel ports with guest and 472 * coded this to react in the same ways that it does. 473 * 474 * The return value from this function is just a hint about where the 475 * handshaking failed. 476 * 477 */ 478 static int ppa_init(ppa_struct *dev) 479 { 480 int retv; 481 unsigned short ppb = dev->base; 482 483 ppa_disconnect(dev); 484 ppa_connect(dev, CONNECT_NORMAL); 485 486 retv = 2; /* Failed */ 487 488 w_ctr(ppb, 0xe); 489 if ((r_str(ppb) & 0x08) == 0x08) 490 retv--; 491 492 w_ctr(ppb, 0xc); 493 if ((r_str(ppb) & 0x08) == 0x00) 494 retv--; 495 496 if (!retv) 497 ppa_reset_pulse(ppb); 498 udelay(1000); /* Allow devices to settle down */ 499 ppa_disconnect(dev); 500 udelay(1000); /* Another delay to allow devices to settle */ 501 502 if (retv) 503 return -EIO; 504 505 return device_check(dev); 506 } 507 508 static inline int ppa_send_command(struct scsi_cmnd *cmd) 509 { 510 ppa_struct *dev = ppa_dev(cmd->device->host); 511 int k; 512 513 w_ctr(dev->base, 0x0c); 514 515 for (k = 0; k < cmd->cmd_len; k++) 516 if (!ppa_out(dev, &cmd->cmnd[k], 1)) 517 return 0; 518 return 1; 519 } 520 521 /* 522 * The bulk flag enables some optimisations in the data transfer loops, 523 * it should be true for any command that transfers data in integral 524 * numbers of sectors. 525 * 526 * The driver appears to remain stable if we speed up the parallel port 527 * i/o in this function, but not elsewhere. 528 */ 529 static int ppa_completion(struct scsi_cmnd *cmd) 530 { 531 /* Return codes: 532 * -1 Error 533 * 0 Told to schedule 534 * 1 Finished data transfer 535 */ 536 ppa_struct *dev = ppa_dev(cmd->device->host); 537 unsigned short ppb = dev->base; 538 unsigned long start_jiffies = jiffies; 539 540 unsigned char r, v; 541 int fast, bulk, status; 542 543 v = cmd->cmnd[0]; 544 bulk = ((v == READ_6) || 545 (v == READ_10) || (v == WRITE_6) || (v == WRITE_10)); 546 547 /* 548 * We only get here if the drive is ready to comunicate, 549 * hence no need for a full ppa_wait. 550 */ 551 r = (r_str(ppb) & 0xf0); 552 553 while (r != (unsigned char) 0xf0) { 554 /* 555 * If we have been running for more than a full timer tick 556 * then take a rest. 557 */ 558 if (time_after(jiffies, start_jiffies + 1)) 559 return 0; 560 561 if ((cmd->SCp.this_residual <= 0)) { 562 ppa_fail(dev, DID_ERROR); 563 return -1; /* ERROR_RETURN */ 564 } 565 566 /* On some hardware we have SCSI disconnected (6th bit low) 567 * for about 100usecs. It is too expensive to wait a 568 * tick on every loop so we busy wait for no more than 569 * 500usecs to give the drive a chance first. We do not 570 * change things for "normal" hardware since generally 571 * the 6th bit is always high. 572 * This makes the CPU load higher on some hardware 573 * but otherwise we can not get more than 50K/secs 574 * on this problem hardware. 575 */ 576 if ((r & 0xc0) != 0xc0) { 577 /* Wait for reconnection should be no more than 578 * jiffy/2 = 5ms = 5000 loops 579 */ 580 unsigned long k = dev->recon_tmo; 581 for (; k && ((r = (r_str(ppb) & 0xf0)) & 0xc0) != 0xc0; 582 k--) 583 udelay(1); 584 585 if (!k) 586 return 0; 587 } 588 589 /* determine if we should use burst I/O */ 590 fast = (bulk && (cmd->SCp.this_residual >= PPA_BURST_SIZE)) 591 ? PPA_BURST_SIZE : 1; 592 593 if (r == (unsigned char) 0xc0) 594 status = ppa_out(dev, cmd->SCp.ptr, fast); 595 else 596 status = ppa_in(dev, cmd->SCp.ptr, fast); 597 598 cmd->SCp.ptr += fast; 599 cmd->SCp.this_residual -= fast; 600 601 if (!status) { 602 ppa_fail(dev, DID_BUS_BUSY); 603 return -1; /* ERROR_RETURN */ 604 } 605 if (cmd->SCp.buffer && !cmd->SCp.this_residual) { 606 /* if scatter/gather, advance to the next segment */ 607 if (cmd->SCp.buffers_residual--) { 608 cmd->SCp.buffer++; 609 cmd->SCp.this_residual = 610 cmd->SCp.buffer->length; 611 cmd->SCp.ptr = 612 page_address(cmd->SCp.buffer->page) + 613 cmd->SCp.buffer->offset; 614 } 615 } 616 /* Now check to see if the drive is ready to comunicate */ 617 r = (r_str(ppb) & 0xf0); 618 /* If not, drop back down to the scheduler and wait a timer tick */ 619 if (!(r & 0x80)) 620 return 0; 621 } 622 return 1; /* FINISH_RETURN */ 623 } 624 625 /* 626 * Since the PPA itself doesn't generate interrupts, we use 627 * the scheduler's task queue to generate a stream of call-backs and 628 * complete the request when the drive is ready. 629 */ 630 static void ppa_interrupt(struct work_struct *work) 631 { 632 ppa_struct *dev = container_of(work, ppa_struct, ppa_tq.work); 633 struct scsi_cmnd *cmd = dev->cur_cmd; 634 635 if (!cmd) { 636 printk("PPA: bug in ppa_interrupt\n"); 637 return; 638 } 639 if (ppa_engine(dev, cmd)) { 640 schedule_delayed_work(&dev->ppa_tq, 1); 641 return; 642 } 643 /* Command must of completed hence it is safe to let go... */ 644 #if PPA_DEBUG > 0 645 switch ((cmd->result >> 16) & 0xff) { 646 case DID_OK: 647 break; 648 case DID_NO_CONNECT: 649 printk("ppa: no device at SCSI ID %i\n", cmd->device->target); 650 break; 651 case DID_BUS_BUSY: 652 printk("ppa: BUS BUSY - EPP timeout detected\n"); 653 break; 654 case DID_TIME_OUT: 655 printk("ppa: unknown timeout\n"); 656 break; 657 case DID_ABORT: 658 printk("ppa: told to abort\n"); 659 break; 660 case DID_PARITY: 661 printk("ppa: parity error (???)\n"); 662 break; 663 case DID_ERROR: 664 printk("ppa: internal driver error\n"); 665 break; 666 case DID_RESET: 667 printk("ppa: told to reset device\n"); 668 break; 669 case DID_BAD_INTR: 670 printk("ppa: bad interrupt (???)\n"); 671 break; 672 default: 673 printk("ppa: bad return code (%02x)\n", 674 (cmd->result >> 16) & 0xff); 675 } 676 #endif 677 678 if (cmd->SCp.phase > 1) 679 ppa_disconnect(dev); 680 681 ppa_pb_dismiss(dev); 682 683 dev->cur_cmd = NULL; 684 685 cmd->scsi_done(cmd); 686 } 687 688 static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd) 689 { 690 unsigned short ppb = dev->base; 691 unsigned char l = 0, h = 0; 692 int retv; 693 694 /* First check for any errors that may of occurred 695 * Here we check for internal errors 696 */ 697 if (dev->failed) 698 return 0; 699 700 switch (cmd->SCp.phase) { 701 case 0: /* Phase 0 - Waiting for parport */ 702 if (time_after(jiffies, dev->jstart + HZ)) { 703 /* 704 * We waited more than a second 705 * for parport to call us 706 */ 707 ppa_fail(dev, DID_BUS_BUSY); 708 return 0; 709 } 710 return 1; /* wait until ppa_wakeup claims parport */ 711 case 1: /* Phase 1 - Connected */ 712 { /* Perform a sanity check for cable unplugged */ 713 int retv = 2; /* Failed */ 714 715 ppa_connect(dev, CONNECT_EPP_MAYBE); 716 717 w_ctr(ppb, 0xe); 718 if ((r_str(ppb) & 0x08) == 0x08) 719 retv--; 720 721 w_ctr(ppb, 0xc); 722 if ((r_str(ppb) & 0x08) == 0x00) 723 retv--; 724 725 if (retv) { 726 if (time_after(jiffies, dev->jstart + (1 * HZ))) { 727 printk 728 ("ppa: Parallel port cable is unplugged!!\n"); 729 ppa_fail(dev, DID_BUS_BUSY); 730 return 0; 731 } else { 732 ppa_disconnect(dev); 733 return 1; /* Try again in a jiffy */ 734 } 735 } 736 cmd->SCp.phase++; 737 } 738 739 case 2: /* Phase 2 - We are now talking to the scsi bus */ 740 if (!ppa_select(dev, scmd_id(cmd))) { 741 ppa_fail(dev, DID_NO_CONNECT); 742 return 0; 743 } 744 cmd->SCp.phase++; 745 746 case 3: /* Phase 3 - Ready to accept a command */ 747 w_ctr(ppb, 0x0c); 748 if (!(r_str(ppb) & 0x80)) 749 return 1; 750 751 if (!ppa_send_command(cmd)) 752 return 0; 753 cmd->SCp.phase++; 754 755 case 4: /* Phase 4 - Setup scatter/gather buffers */ 756 if (cmd->use_sg) { 757 /* if many buffers are available, start filling the first */ 758 cmd->SCp.buffer = 759 (struct scatterlist *) cmd->request_buffer; 760 cmd->SCp.this_residual = cmd->SCp.buffer->length; 761 cmd->SCp.ptr = 762 page_address(cmd->SCp.buffer->page) + 763 cmd->SCp.buffer->offset; 764 } else { 765 /* else fill the only available buffer */ 766 cmd->SCp.buffer = NULL; 767 cmd->SCp.this_residual = cmd->request_bufflen; 768 cmd->SCp.ptr = cmd->request_buffer; 769 } 770 cmd->SCp.buffers_residual = cmd->use_sg - 1; 771 cmd->SCp.phase++; 772 773 case 5: /* Phase 5 - Data transfer stage */ 774 w_ctr(ppb, 0x0c); 775 if (!(r_str(ppb) & 0x80)) 776 return 1; 777 778 retv = ppa_completion(cmd); 779 if (retv == -1) 780 return 0; 781 if (retv == 0) 782 return 1; 783 cmd->SCp.phase++; 784 785 case 6: /* Phase 6 - Read status/message */ 786 cmd->result = DID_OK << 16; 787 /* Check for data overrun */ 788 if (ppa_wait(dev) != (unsigned char) 0xf0) { 789 ppa_fail(dev, DID_ERROR); 790 return 0; 791 } 792 if (ppa_in(dev, &l, 1)) { /* read status byte */ 793 /* Check for optional message byte */ 794 if (ppa_wait(dev) == (unsigned char) 0xf0) 795 ppa_in(dev, &h, 1); 796 cmd->result = 797 (DID_OK << 16) + (h << 8) + (l & STATUS_MASK); 798 } 799 return 0; /* Finished */ 800 break; 801 802 default: 803 printk("ppa: Invalid scsi phase\n"); 804 } 805 return 0; 806 } 807 808 static int ppa_queuecommand(struct scsi_cmnd *cmd, 809 void (*done) (struct scsi_cmnd *)) 810 { 811 ppa_struct *dev = ppa_dev(cmd->device->host); 812 813 if (dev->cur_cmd) { 814 printk("PPA: bug in ppa_queuecommand\n"); 815 return 0; 816 } 817 dev->failed = 0; 818 dev->jstart = jiffies; 819 dev->cur_cmd = cmd; 820 cmd->scsi_done = done; 821 cmd->result = DID_ERROR << 16; /* default return code */ 822 cmd->SCp.phase = 0; /* bus free */ 823 824 schedule_delayed_work(&dev->ppa_tq, 0); 825 826 ppa_pb_claim(dev); 827 828 return 0; 829 } 830 831 /* 832 * Apparently the disk->capacity attribute is off by 1 sector 833 * for all disk drives. We add the one here, but it should really 834 * be done in sd.c. Even if it gets fixed there, this will still 835 * work. 836 */ 837 static int ppa_biosparam(struct scsi_device *sdev, struct block_device *dev, 838 sector_t capacity, int ip[]) 839 { 840 ip[0] = 0x40; 841 ip[1] = 0x20; 842 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]); 843 if (ip[2] > 1024) { 844 ip[0] = 0xff; 845 ip[1] = 0x3f; 846 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]); 847 if (ip[2] > 1023) 848 ip[2] = 1023; 849 } 850 return 0; 851 } 852 853 static int ppa_abort(struct scsi_cmnd *cmd) 854 { 855 ppa_struct *dev = ppa_dev(cmd->device->host); 856 /* 857 * There is no method for aborting commands since Iomega 858 * have tied the SCSI_MESSAGE line high in the interface 859 */ 860 861 switch (cmd->SCp.phase) { 862 case 0: /* Do not have access to parport */ 863 case 1: /* Have not connected to interface */ 864 dev->cur_cmd = NULL; /* Forget the problem */ 865 return SUCCESS; 866 break; 867 default: /* SCSI command sent, can not abort */ 868 return FAILED; 869 break; 870 } 871 } 872 873 static void ppa_reset_pulse(unsigned int base) 874 { 875 w_dtr(base, 0x40); 876 w_ctr(base, 0x8); 877 udelay(30); 878 w_ctr(base, 0xc); 879 } 880 881 static int ppa_reset(struct scsi_cmnd *cmd) 882 { 883 ppa_struct *dev = ppa_dev(cmd->device->host); 884 885 if (cmd->SCp.phase) 886 ppa_disconnect(dev); 887 dev->cur_cmd = NULL; /* Forget the problem */ 888 889 ppa_connect(dev, CONNECT_NORMAL); 890 ppa_reset_pulse(dev->base); 891 mdelay(1); /* device settle delay */ 892 ppa_disconnect(dev); 893 mdelay(1); /* device settle delay */ 894 return SUCCESS; 895 } 896 897 static int device_check(ppa_struct *dev) 898 { 899 /* This routine looks for a device and then attempts to use EPP 900 to send a command. If all goes as planned then EPP is available. */ 901 902 static char cmd[6] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 903 int loop, old_mode, status, k, ppb = dev->base; 904 unsigned char l; 905 906 old_mode = dev->mode; 907 for (loop = 0; loop < 8; loop++) { 908 /* Attempt to use EPP for Test Unit Ready */ 909 if ((ppb & 0x0007) == 0x0000) 910 dev->mode = PPA_EPP_32; 911 912 second_pass: 913 ppa_connect(dev, CONNECT_EPP_MAYBE); 914 /* Select SCSI device */ 915 if (!ppa_select(dev, loop)) { 916 ppa_disconnect(dev); 917 continue; 918 } 919 printk("ppa: Found device at ID %i, Attempting to use %s\n", 920 loop, PPA_MODE_STRING[dev->mode]); 921 922 /* Send SCSI command */ 923 status = 1; 924 w_ctr(ppb, 0x0c); 925 for (l = 0; (l < 6) && (status); l++) 926 status = ppa_out(dev, cmd, 1); 927 928 if (!status) { 929 ppa_disconnect(dev); 930 ppa_connect(dev, CONNECT_EPP_MAYBE); 931 w_dtr(ppb, 0x40); 932 w_ctr(ppb, 0x08); 933 udelay(30); 934 w_ctr(ppb, 0x0c); 935 udelay(1000); 936 ppa_disconnect(dev); 937 udelay(1000); 938 if (dev->mode == PPA_EPP_32) { 939 dev->mode = old_mode; 940 goto second_pass; 941 } 942 return -EIO; 943 } 944 w_ctr(ppb, 0x0c); 945 k = 1000000; /* 1 Second */ 946 do { 947 l = r_str(ppb); 948 k--; 949 udelay(1); 950 } while (!(l & 0x80) && (k)); 951 952 l &= 0xf0; 953 954 if (l != 0xf0) { 955 ppa_disconnect(dev); 956 ppa_connect(dev, CONNECT_EPP_MAYBE); 957 ppa_reset_pulse(ppb); 958 udelay(1000); 959 ppa_disconnect(dev); 960 udelay(1000); 961 if (dev->mode == PPA_EPP_32) { 962 dev->mode = old_mode; 963 goto second_pass; 964 } 965 return -EIO; 966 } 967 ppa_disconnect(dev); 968 printk("ppa: Communication established with ID %i using %s\n", 969 loop, PPA_MODE_STRING[dev->mode]); 970 ppa_connect(dev, CONNECT_EPP_MAYBE); 971 ppa_reset_pulse(ppb); 972 udelay(1000); 973 ppa_disconnect(dev); 974 udelay(1000); 975 return 0; 976 } 977 return -ENODEV; 978 } 979 980 static int ppa_adjust_queue(struct scsi_device *device) 981 { 982 blk_queue_bounce_limit(device->request_queue, BLK_BOUNCE_HIGH); 983 return 0; 984 } 985 986 static struct scsi_host_template ppa_template = { 987 .module = THIS_MODULE, 988 .proc_name = "ppa", 989 .proc_info = ppa_proc_info, 990 .name = "Iomega VPI0 (ppa) interface", 991 .queuecommand = ppa_queuecommand, 992 .eh_abort_handler = ppa_abort, 993 .eh_bus_reset_handler = ppa_reset, 994 .eh_host_reset_handler = ppa_reset, 995 .bios_param = ppa_biosparam, 996 .this_id = -1, 997 .sg_tablesize = SG_ALL, 998 .cmd_per_lun = 1, 999 .use_clustering = ENABLE_CLUSTERING, 1000 .can_queue = 1, 1001 .slave_alloc = ppa_adjust_queue, 1002 }; 1003 1004 /*************************************************************************** 1005 * Parallel port probing routines * 1006 ***************************************************************************/ 1007 1008 static LIST_HEAD(ppa_hosts); 1009 1010 static int __ppa_attach(struct parport *pb) 1011 { 1012 struct Scsi_Host *host; 1013 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(waiting); 1014 DEFINE_WAIT(wait); 1015 ppa_struct *dev; 1016 int ports; 1017 int modes, ppb, ppb_hi; 1018 int err = -ENOMEM; 1019 1020 dev = kmalloc(sizeof(ppa_struct), GFP_KERNEL); 1021 if (!dev) 1022 return -ENOMEM; 1023 memset(dev, 0, sizeof(ppa_struct)); 1024 dev->base = -1; 1025 dev->mode = PPA_AUTODETECT; 1026 dev->recon_tmo = PPA_RECON_TMO; 1027 init_waitqueue_head(&waiting); 1028 dev->dev = parport_register_device(pb, "ppa", NULL, ppa_wakeup, 1029 NULL, 0, dev); 1030 1031 if (!dev->dev) 1032 goto out; 1033 1034 /* Claim the bus so it remembers what we do to the control 1035 * registers. [ CTR and ECP ] 1036 */ 1037 err = -EBUSY; 1038 dev->waiting = &waiting; 1039 prepare_to_wait(&waiting, &wait, TASK_UNINTERRUPTIBLE); 1040 if (ppa_pb_claim(dev)) 1041 schedule_timeout(3 * HZ); 1042 if (dev->wanted) { 1043 printk(KERN_ERR "ppa%d: failed to claim parport because " 1044 "a pardevice is owning the port for too long " 1045 "time!\n", pb->number); 1046 ppa_pb_dismiss(dev); 1047 dev->waiting = NULL; 1048 finish_wait(&waiting, &wait); 1049 goto out1; 1050 } 1051 dev->waiting = NULL; 1052 finish_wait(&waiting, &wait); 1053 ppb = dev->base = dev->dev->port->base; 1054 ppb_hi = dev->dev->port->base_hi; 1055 w_ctr(ppb, 0x0c); 1056 modes = dev->dev->port->modes; 1057 1058 /* Mode detection works up the chain of speed 1059 * This avoids a nasty if-then-else-if-... tree 1060 */ 1061 dev->mode = PPA_NIBBLE; 1062 1063 if (modes & PARPORT_MODE_TRISTATE) 1064 dev->mode = PPA_PS2; 1065 1066 if (modes & PARPORT_MODE_ECP) { 1067 w_ecr(ppb_hi, 0x20); 1068 dev->mode = PPA_PS2; 1069 } 1070 if ((modes & PARPORT_MODE_EPP) && (modes & PARPORT_MODE_ECP)) 1071 w_ecr(ppb_hi, 0x80); 1072 1073 /* Done configuration */ 1074 1075 err = ppa_init(dev); 1076 ppa_pb_release(dev); 1077 1078 if (err) 1079 goto out1; 1080 1081 /* now the glue ... */ 1082 if (dev->mode == PPA_NIBBLE || dev->mode == PPA_PS2) 1083 ports = 3; 1084 else 1085 ports = 8; 1086 1087 INIT_DELAYED_WORK(&dev->ppa_tq, ppa_interrupt); 1088 1089 err = -ENOMEM; 1090 host = scsi_host_alloc(&ppa_template, sizeof(ppa_struct *)); 1091 if (!host) 1092 goto out1; 1093 host->io_port = pb->base; 1094 host->n_io_port = ports; 1095 host->dma_channel = -1; 1096 host->unique_id = pb->number; 1097 *(ppa_struct **)&host->hostdata = dev; 1098 dev->host = host; 1099 list_add_tail(&dev->list, &ppa_hosts); 1100 err = scsi_add_host(host, NULL); 1101 if (err) 1102 goto out2; 1103 scsi_scan_host(host); 1104 return 0; 1105 out2: 1106 list_del_init(&dev->list); 1107 scsi_host_put(host); 1108 out1: 1109 parport_unregister_device(dev->dev); 1110 out: 1111 kfree(dev); 1112 return err; 1113 } 1114 1115 static void ppa_attach(struct parport *pb) 1116 { 1117 __ppa_attach(pb); 1118 } 1119 1120 static void ppa_detach(struct parport *pb) 1121 { 1122 ppa_struct *dev; 1123 list_for_each_entry(dev, &ppa_hosts, list) { 1124 if (dev->dev->port == pb) { 1125 list_del_init(&dev->list); 1126 scsi_remove_host(dev->host); 1127 scsi_host_put(dev->host); 1128 parport_unregister_device(dev->dev); 1129 kfree(dev); 1130 break; 1131 } 1132 } 1133 } 1134 1135 static struct parport_driver ppa_driver = { 1136 .name = "ppa", 1137 .attach = ppa_attach, 1138 .detach = ppa_detach, 1139 }; 1140 1141 static int __init ppa_driver_init(void) 1142 { 1143 printk("ppa: Version %s\n", PPA_VERSION); 1144 return parport_register_driver(&ppa_driver); 1145 } 1146 1147 static void __exit ppa_driver_exit(void) 1148 { 1149 parport_unregister_driver(&ppa_driver); 1150 } 1151 1152 module_init(ppa_driver_init); 1153 module_exit(ppa_driver_exit); 1154 MODULE_LICENSE("GPL"); 1155