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/slab.h> 14 #include <linux/module.h> 15 #include <linux/blkdev.h> 16 #include <linux/parport.h> 17 #include <linux/workqueue.h> 18 #include <linux/delay.h> 19 #include <linux/jiffies.h> 20 #include <asm/io.h> 21 22 #include <scsi/scsi.h> 23 #include <scsi/scsi_cmnd.h> 24 #include <scsi/scsi_device.h> 25 #include <scsi/scsi_host.h> 26 27 28 static void ppa_reset_pulse(unsigned int base); 29 30 typedef struct { 31 struct pardevice *dev; /* Parport device entry */ 32 int base; /* Actual port address */ 33 int mode; /* Transfer mode */ 34 struct scsi_cmnd *cur_cmd; /* Current queued command */ 35 struct delayed_work ppa_tq; /* Polling interrupt stuff */ 36 unsigned long jstart; /* Jiffies at start */ 37 unsigned long recon_tmo; /* How many usecs to wait for reconnection (6th bit) */ 38 unsigned int failed:1; /* Failure flag */ 39 unsigned wanted:1; /* Parport sharing busy flag */ 40 wait_queue_head_t *waiting; 41 struct Scsi_Host *host; 42 struct list_head list; 43 } ppa_struct; 44 45 #include "ppa.h" 46 47 static inline ppa_struct *ppa_dev(struct Scsi_Host *host) 48 { 49 return *(ppa_struct **)&host->hostdata; 50 } 51 52 static DEFINE_SPINLOCK(arbitration_lock); 53 54 static void got_it(ppa_struct *dev) 55 { 56 dev->base = dev->dev->port->base; 57 if (dev->cur_cmd) 58 dev->cur_cmd->SCp.phase = 1; 59 else 60 wake_up(dev->waiting); 61 } 62 63 static void ppa_wakeup(void *ref) 64 { 65 ppa_struct *dev = (ppa_struct *) ref; 66 unsigned long flags; 67 68 spin_lock_irqsave(&arbitration_lock, flags); 69 if (dev->wanted) { 70 parport_claim(dev->dev); 71 got_it(dev); 72 dev->wanted = 0; 73 } 74 spin_unlock_irqrestore(&arbitration_lock, flags); 75 return; 76 } 77 78 static int ppa_pb_claim(ppa_struct *dev) 79 { 80 unsigned long flags; 81 int res = 1; 82 spin_lock_irqsave(&arbitration_lock, flags); 83 if (parport_claim(dev->dev) == 0) { 84 got_it(dev); 85 res = 0; 86 } 87 dev->wanted = res; 88 spin_unlock_irqrestore(&arbitration_lock, flags); 89 return res; 90 } 91 92 static void ppa_pb_dismiss(ppa_struct *dev) 93 { 94 unsigned long flags; 95 int wanted; 96 spin_lock_irqsave(&arbitration_lock, flags); 97 wanted = dev->wanted; 98 dev->wanted = 0; 99 spin_unlock_irqrestore(&arbitration_lock, flags); 100 if (!wanted) 101 parport_release(dev->dev); 102 } 103 104 static inline void ppa_pb_release(ppa_struct *dev) 105 { 106 parport_release(dev->dev); 107 } 108 109 /* 110 * Start of Chipset kludges 111 */ 112 113 /* This is to give the ppa driver a way to modify the timings (and other 114 * parameters) by writing to the /proc/scsi/ppa/0 file. 115 * Very simple method really... (To simple, no error checking :( ) 116 * Reason: Kernel hackers HATE having to unload and reload modules for 117 * testing... 118 * Also gives a method to use a script to obtain optimum timings (TODO) 119 */ 120 121 static inline int ppa_proc_write(ppa_struct *dev, char *buffer, int length) 122 { 123 unsigned long x; 124 125 if ((length > 5) && (strncmp(buffer, "mode=", 5) == 0)) { 126 x = simple_strtoul(buffer + 5, NULL, 0); 127 dev->mode = x; 128 return length; 129 } 130 if ((length > 10) && (strncmp(buffer, "recon_tmo=", 10) == 0)) { 131 x = simple_strtoul(buffer + 10, NULL, 0); 132 dev->recon_tmo = x; 133 printk(KERN_INFO "ppa: recon_tmo set to %ld\n", x); 134 return length; 135 } 136 printk(KERN_WARNING "ppa /proc: invalid variable\n"); 137 return -EINVAL; 138 } 139 140 static int ppa_proc_info(struct Scsi_Host *host, char *buffer, char **start, off_t offset, int length, int inout) 141 { 142 int len = 0; 143 ppa_struct *dev = ppa_dev(host); 144 145 if (inout) 146 return ppa_proc_write(dev, buffer, length); 147 148 len += sprintf(buffer + len, "Version : %s\n", PPA_VERSION); 149 len += 150 sprintf(buffer + len, "Parport : %s\n", 151 dev->dev->port->name); 152 len += 153 sprintf(buffer + len, "Mode : %s\n", 154 PPA_MODE_STRING[dev->mode]); 155 #if PPA_DEBUG > 0 156 len += 157 sprintf(buffer + len, "recon_tmo : %lu\n", dev->recon_tmo); 158 #endif 159 160 /* Request for beyond end of buffer */ 161 if (offset > length) 162 return 0; 163 164 *start = buffer + offset; 165 len -= offset; 166 if (len > length) 167 len = length; 168 return len; 169 } 170 171 static int device_check(ppa_struct *dev); 172 173 #if PPA_DEBUG > 0 174 #define ppa_fail(x,y) printk("ppa: ppa_fail(%i) from %s at line %d\n",\ 175 y, __func__, __LINE__); ppa_fail_func(x,y); 176 static inline void ppa_fail_func(ppa_struct *dev, int error_code) 177 #else 178 static inline void ppa_fail(ppa_struct *dev, int error_code) 179 #endif 180 { 181 /* If we fail a device then we trash status / message bytes */ 182 if (dev->cur_cmd) { 183 dev->cur_cmd->result = error_code << 16; 184 dev->failed = 1; 185 } 186 } 187 188 /* 189 * Wait for the high bit to be set. 190 * 191 * In principle, this could be tied to an interrupt, but the adapter 192 * doesn't appear to be designed to support interrupts. We spin on 193 * the 0x80 ready bit. 194 */ 195 static unsigned char ppa_wait(ppa_struct *dev) 196 { 197 int k; 198 unsigned short ppb = dev->base; 199 unsigned char r; 200 201 k = PPA_SPIN_TMO; 202 /* Wait for bit 6 and 7 - PJC */ 203 for (r = r_str(ppb); ((r & 0xc0) != 0xc0) && (k); k--) { 204 udelay(1); 205 r = r_str(ppb); 206 } 207 208 /* 209 * return some status information. 210 * Semantics: 0xc0 = ZIP wants more data 211 * 0xd0 = ZIP wants to send more data 212 * 0xe0 = ZIP is expecting SCSI command data 213 * 0xf0 = end of transfer, ZIP is sending status 214 */ 215 if (k) 216 return (r & 0xf0); 217 218 /* Counter expired - Time out occurred */ 219 ppa_fail(dev, DID_TIME_OUT); 220 printk(KERN_WARNING "ppa timeout in ppa_wait\n"); 221 return 0; /* command timed out */ 222 } 223 224 /* 225 * Clear EPP Timeout Bit 226 */ 227 static inline void epp_reset(unsigned short ppb) 228 { 229 int i; 230 231 i = r_str(ppb); 232 w_str(ppb, i); 233 w_str(ppb, i & 0xfe); 234 } 235 236 /* 237 * Wait for empty ECP fifo (if we are in ECP fifo mode only) 238 */ 239 static inline void ecp_sync(ppa_struct *dev) 240 { 241 int i, ppb_hi = dev->dev->port->base_hi; 242 243 if (ppb_hi == 0) 244 return; 245 246 if ((r_ecr(ppb_hi) & 0xe0) == 0x60) { /* mode 011 == ECP fifo mode */ 247 for (i = 0; i < 100; i++) { 248 if (r_ecr(ppb_hi) & 0x01) 249 return; 250 udelay(5); 251 } 252 printk(KERN_WARNING "ppa: ECP sync failed as data still present in FIFO.\n"); 253 } 254 } 255 256 static int ppa_byte_out(unsigned short base, const char *buffer, int len) 257 { 258 int i; 259 260 for (i = len; i; i--) { 261 w_dtr(base, *buffer++); 262 w_ctr(base, 0xe); 263 w_ctr(base, 0xc); 264 } 265 return 1; /* All went well - we hope! */ 266 } 267 268 static int ppa_byte_in(unsigned short base, char *buffer, int len) 269 { 270 int i; 271 272 for (i = len; i; i--) { 273 *buffer++ = r_dtr(base); 274 w_ctr(base, 0x27); 275 w_ctr(base, 0x25); 276 } 277 return 1; /* All went well - we hope! */ 278 } 279 280 static int ppa_nibble_in(unsigned short base, char *buffer, int len) 281 { 282 for (; len; len--) { 283 unsigned char h; 284 285 w_ctr(base, 0x4); 286 h = r_str(base) & 0xf0; 287 w_ctr(base, 0x6); 288 *buffer++ = h | ((r_str(base) & 0xf0) >> 4); 289 } 290 return 1; /* All went well - we hope! */ 291 } 292 293 static int ppa_out(ppa_struct *dev, char *buffer, int len) 294 { 295 int r; 296 unsigned short ppb = dev->base; 297 298 r = ppa_wait(dev); 299 300 if ((r & 0x50) != 0x40) { 301 ppa_fail(dev, DID_ERROR); 302 return 0; 303 } 304 switch (dev->mode) { 305 case PPA_NIBBLE: 306 case PPA_PS2: 307 /* 8 bit output, with a loop */ 308 r = ppa_byte_out(ppb, buffer, len); 309 break; 310 311 case PPA_EPP_32: 312 case PPA_EPP_16: 313 case PPA_EPP_8: 314 epp_reset(ppb); 315 w_ctr(ppb, 0x4); 316 #ifdef CONFIG_SCSI_IZIP_EPP16 317 if (!(((long) buffer | len) & 0x01)) 318 outsw(ppb + 4, buffer, len >> 1); 319 #else 320 if (!(((long) buffer | len) & 0x03)) 321 outsl(ppb + 4, buffer, len >> 2); 322 #endif 323 else 324 outsb(ppb + 4, buffer, len); 325 w_ctr(ppb, 0xc); 326 r = !(r_str(ppb) & 0x01); 327 w_ctr(ppb, 0xc); 328 ecp_sync(dev); 329 break; 330 331 default: 332 printk(KERN_ERR "PPA: bug in ppa_out()\n"); 333 r = 0; 334 } 335 return r; 336 } 337 338 static int ppa_in(ppa_struct *dev, char *buffer, int len) 339 { 340 int r; 341 unsigned short ppb = dev->base; 342 343 r = ppa_wait(dev); 344 345 if ((r & 0x50) != 0x50) { 346 ppa_fail(dev, DID_ERROR); 347 return 0; 348 } 349 switch (dev->mode) { 350 case PPA_NIBBLE: 351 /* 4 bit input, with a loop */ 352 r = ppa_nibble_in(ppb, buffer, len); 353 w_ctr(ppb, 0xc); 354 break; 355 356 case PPA_PS2: 357 /* 8 bit input, with a loop */ 358 w_ctr(ppb, 0x25); 359 r = ppa_byte_in(ppb, buffer, len); 360 w_ctr(ppb, 0x4); 361 w_ctr(ppb, 0xc); 362 break; 363 364 case PPA_EPP_32: 365 case PPA_EPP_16: 366 case PPA_EPP_8: 367 epp_reset(ppb); 368 w_ctr(ppb, 0x24); 369 #ifdef CONFIG_SCSI_IZIP_EPP16 370 if (!(((long) buffer | len) & 0x01)) 371 insw(ppb + 4, buffer, len >> 1); 372 #else 373 if (!(((long) buffer | len) & 0x03)) 374 insl(ppb + 4, buffer, len >> 2); 375 #endif 376 else 377 insb(ppb + 4, buffer, len); 378 w_ctr(ppb, 0x2c); 379 r = !(r_str(ppb) & 0x01); 380 w_ctr(ppb, 0x2c); 381 ecp_sync(dev); 382 break; 383 384 default: 385 printk(KERN_ERR "PPA: bug in ppa_ins()\n"); 386 r = 0; 387 break; 388 } 389 return r; 390 } 391 392 /* end of ppa_io.h */ 393 static inline void ppa_d_pulse(unsigned short ppb, unsigned char b) 394 { 395 w_dtr(ppb, b); 396 w_ctr(ppb, 0xc); 397 w_ctr(ppb, 0xe); 398 w_ctr(ppb, 0xc); 399 w_ctr(ppb, 0x4); 400 w_ctr(ppb, 0xc); 401 } 402 403 static void ppa_disconnect(ppa_struct *dev) 404 { 405 unsigned short ppb = dev->base; 406 407 ppa_d_pulse(ppb, 0); 408 ppa_d_pulse(ppb, 0x3c); 409 ppa_d_pulse(ppb, 0x20); 410 ppa_d_pulse(ppb, 0xf); 411 } 412 413 static inline void ppa_c_pulse(unsigned short ppb, unsigned char b) 414 { 415 w_dtr(ppb, b); 416 w_ctr(ppb, 0x4); 417 w_ctr(ppb, 0x6); 418 w_ctr(ppb, 0x4); 419 w_ctr(ppb, 0xc); 420 } 421 422 static inline void ppa_connect(ppa_struct *dev, int flag) 423 { 424 unsigned short ppb = dev->base; 425 426 ppa_c_pulse(ppb, 0); 427 ppa_c_pulse(ppb, 0x3c); 428 ppa_c_pulse(ppb, 0x20); 429 if ((flag == CONNECT_EPP_MAYBE) && IN_EPP_MODE(dev->mode)) 430 ppa_c_pulse(ppb, 0xcf); 431 else 432 ppa_c_pulse(ppb, 0x8f); 433 } 434 435 static int ppa_select(ppa_struct *dev, int target) 436 { 437 int k; 438 unsigned short ppb = dev->base; 439 440 /* 441 * Bit 6 (0x40) is the device selected bit. 442 * First we must wait till the current device goes off line... 443 */ 444 k = PPA_SELECT_TMO; 445 do { 446 k--; 447 udelay(1); 448 } while ((r_str(ppb) & 0x40) && (k)); 449 if (!k) 450 return 0; 451 452 w_dtr(ppb, (1 << target)); 453 w_ctr(ppb, 0xe); 454 w_ctr(ppb, 0xc); 455 w_dtr(ppb, 0x80); /* This is NOT the initator */ 456 w_ctr(ppb, 0x8); 457 458 k = PPA_SELECT_TMO; 459 do { 460 k--; 461 udelay(1); 462 } 463 while (!(r_str(ppb) & 0x40) && (k)); 464 if (!k) 465 return 0; 466 467 return 1; 468 } 469 470 /* 471 * This is based on a trace of what the Iomega DOS 'guest' driver does. 472 * I've tried several different kinds of parallel ports with guest and 473 * coded this to react in the same ways that it does. 474 * 475 * The return value from this function is just a hint about where the 476 * handshaking failed. 477 * 478 */ 479 static int ppa_init(ppa_struct *dev) 480 { 481 int retv; 482 unsigned short ppb = dev->base; 483 484 ppa_disconnect(dev); 485 ppa_connect(dev, CONNECT_NORMAL); 486 487 retv = 2; /* Failed */ 488 489 w_ctr(ppb, 0xe); 490 if ((r_str(ppb) & 0x08) == 0x08) 491 retv--; 492 493 w_ctr(ppb, 0xc); 494 if ((r_str(ppb) & 0x08) == 0x00) 495 retv--; 496 497 if (!retv) 498 ppa_reset_pulse(ppb); 499 udelay(1000); /* Allow devices to settle down */ 500 ppa_disconnect(dev); 501 udelay(1000); /* Another delay to allow devices to settle */ 502 503 if (retv) 504 return -EIO; 505 506 return device_check(dev); 507 } 508 509 static inline int ppa_send_command(struct scsi_cmnd *cmd) 510 { 511 ppa_struct *dev = ppa_dev(cmd->device->host); 512 int k; 513 514 w_ctr(dev->base, 0x0c); 515 516 for (k = 0; k < cmd->cmd_len; k++) 517 if (!ppa_out(dev, &cmd->cmnd[k], 1)) 518 return 0; 519 return 1; 520 } 521 522 /* 523 * The bulk flag enables some optimisations in the data transfer loops, 524 * it should be true for any command that transfers data in integral 525 * numbers of sectors. 526 * 527 * The driver appears to remain stable if we speed up the parallel port 528 * i/o in this function, but not elsewhere. 529 */ 530 static int ppa_completion(struct scsi_cmnd *cmd) 531 { 532 /* Return codes: 533 * -1 Error 534 * 0 Told to schedule 535 * 1 Finished data transfer 536 */ 537 ppa_struct *dev = ppa_dev(cmd->device->host); 538 unsigned short ppb = dev->base; 539 unsigned long start_jiffies = jiffies; 540 541 unsigned char r, v; 542 int fast, bulk, status; 543 544 v = cmd->cmnd[0]; 545 bulk = ((v == READ_6) || 546 (v == READ_10) || (v == WRITE_6) || (v == WRITE_10)); 547 548 /* 549 * We only get here if the drive is ready to comunicate, 550 * hence no need for a full ppa_wait. 551 */ 552 r = (r_str(ppb) & 0xf0); 553 554 while (r != (unsigned char) 0xf0) { 555 /* 556 * If we have been running for more than a full timer tick 557 * then take a rest. 558 */ 559 if (time_after(jiffies, start_jiffies + 1)) 560 return 0; 561 562 if ((cmd->SCp.this_residual <= 0)) { 563 ppa_fail(dev, DID_ERROR); 564 return -1; /* ERROR_RETURN */ 565 } 566 567 /* On some hardware we have SCSI disconnected (6th bit low) 568 * for about 100usecs. It is too expensive to wait a 569 * tick on every loop so we busy wait for no more than 570 * 500usecs to give the drive a chance first. We do not 571 * change things for "normal" hardware since generally 572 * the 6th bit is always high. 573 * This makes the CPU load higher on some hardware 574 * but otherwise we can not get more than 50K/secs 575 * on this problem hardware. 576 */ 577 if ((r & 0xc0) != 0xc0) { 578 /* Wait for reconnection should be no more than 579 * jiffy/2 = 5ms = 5000 loops 580 */ 581 unsigned long k = dev->recon_tmo; 582 for (; k && ((r = (r_str(ppb) & 0xf0)) & 0xc0) != 0xc0; 583 k--) 584 udelay(1); 585 586 if (!k) 587 return 0; 588 } 589 590 /* determine if we should use burst I/O */ 591 fast = (bulk && (cmd->SCp.this_residual >= PPA_BURST_SIZE)) 592 ? PPA_BURST_SIZE : 1; 593 594 if (r == (unsigned char) 0xc0) 595 status = ppa_out(dev, cmd->SCp.ptr, fast); 596 else 597 status = ppa_in(dev, cmd->SCp.ptr, fast); 598 599 cmd->SCp.ptr += fast; 600 cmd->SCp.this_residual -= fast; 601 602 if (!status) { 603 ppa_fail(dev, DID_BUS_BUSY); 604 return -1; /* ERROR_RETURN */ 605 } 606 if (cmd->SCp.buffer && !cmd->SCp.this_residual) { 607 /* if scatter/gather, advance to the next segment */ 608 if (cmd->SCp.buffers_residual--) { 609 cmd->SCp.buffer++; 610 cmd->SCp.this_residual = 611 cmd->SCp.buffer->length; 612 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); 613 } 614 } 615 /* Now check to see if the drive is ready to comunicate */ 616 r = (r_str(ppb) & 0xf0); 617 /* If not, drop back down to the scheduler and wait a timer tick */ 618 if (!(r & 0x80)) 619 return 0; 620 } 621 return 1; /* FINISH_RETURN */ 622 } 623 624 /* 625 * Since the PPA itself doesn't generate interrupts, we use 626 * the scheduler's task queue to generate a stream of call-backs and 627 * complete the request when the drive is ready. 628 */ 629 static void ppa_interrupt(struct work_struct *work) 630 { 631 ppa_struct *dev = container_of(work, ppa_struct, ppa_tq.work); 632 struct scsi_cmnd *cmd = dev->cur_cmd; 633 634 if (!cmd) { 635 printk(KERN_ERR "PPA: bug in ppa_interrupt\n"); 636 return; 637 } 638 if (ppa_engine(dev, cmd)) { 639 schedule_delayed_work(&dev->ppa_tq, 1); 640 return; 641 } 642 /* Command must of completed hence it is safe to let go... */ 643 #if PPA_DEBUG > 0 644 switch ((cmd->result >> 16) & 0xff) { 645 case DID_OK: 646 break; 647 case DID_NO_CONNECT: 648 printk(KERN_DEBUG "ppa: no device at SCSI ID %i\n", cmd->device->target); 649 break; 650 case DID_BUS_BUSY: 651 printk(KERN_DEBUG "ppa: BUS BUSY - EPP timeout detected\n"); 652 break; 653 case DID_TIME_OUT: 654 printk(KERN_DEBUG "ppa: unknown timeout\n"); 655 break; 656 case DID_ABORT: 657 printk(KERN_DEBUG "ppa: told to abort\n"); 658 break; 659 case DID_PARITY: 660 printk(KERN_DEBUG "ppa: parity error (???)\n"); 661 break; 662 case DID_ERROR: 663 printk(KERN_DEBUG "ppa: internal driver error\n"); 664 break; 665 case DID_RESET: 666 printk(KERN_DEBUG "ppa: told to reset device\n"); 667 break; 668 case DID_BAD_INTR: 669 printk(KERN_WARNING "ppa: bad interrupt (???)\n"); 670 break; 671 default: 672 printk(KERN_WARNING "ppa: bad return code (%02x)\n", 673 (cmd->result >> 16) & 0xff); 674 } 675 #endif 676 677 if (cmd->SCp.phase > 1) 678 ppa_disconnect(dev); 679 680 ppa_pb_dismiss(dev); 681 682 dev->cur_cmd = NULL; 683 684 cmd->scsi_done(cmd); 685 } 686 687 static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd) 688 { 689 unsigned short ppb = dev->base; 690 unsigned char l = 0, h = 0; 691 int retv; 692 693 /* First check for any errors that may of occurred 694 * Here we check for internal errors 695 */ 696 if (dev->failed) 697 return 0; 698 699 switch (cmd->SCp.phase) { 700 case 0: /* Phase 0 - Waiting for parport */ 701 if (time_after(jiffies, dev->jstart + HZ)) { 702 /* 703 * We waited more than a second 704 * for parport to call us 705 */ 706 ppa_fail(dev, DID_BUS_BUSY); 707 return 0; 708 } 709 return 1; /* wait until ppa_wakeup claims parport */ 710 case 1: /* Phase 1 - Connected */ 711 { /* Perform a sanity check for cable unplugged */ 712 int retv = 2; /* Failed */ 713 714 ppa_connect(dev, CONNECT_EPP_MAYBE); 715 716 w_ctr(ppb, 0xe); 717 if ((r_str(ppb) & 0x08) == 0x08) 718 retv--; 719 720 w_ctr(ppb, 0xc); 721 if ((r_str(ppb) & 0x08) == 0x00) 722 retv--; 723 724 if (retv) { 725 if (time_after(jiffies, dev->jstart + (1 * HZ))) { 726 printk(KERN_ERR "ppa: Parallel port cable is unplugged.\n"); 727 ppa_fail(dev, DID_BUS_BUSY); 728 return 0; 729 } else { 730 ppa_disconnect(dev); 731 return 1; /* Try again in a jiffy */ 732 } 733 } 734 cmd->SCp.phase++; 735 } 736 737 case 2: /* Phase 2 - We are now talking to the scsi bus */ 738 if (!ppa_select(dev, scmd_id(cmd))) { 739 ppa_fail(dev, DID_NO_CONNECT); 740 return 0; 741 } 742 cmd->SCp.phase++; 743 744 case 3: /* Phase 3 - Ready to accept a command */ 745 w_ctr(ppb, 0x0c); 746 if (!(r_str(ppb) & 0x80)) 747 return 1; 748 749 if (!ppa_send_command(cmd)) 750 return 0; 751 cmd->SCp.phase++; 752 753 case 4: /* Phase 4 - Setup scatter/gather buffers */ 754 if (scsi_bufflen(cmd)) { 755 cmd->SCp.buffer = scsi_sglist(cmd); 756 cmd->SCp.this_residual = cmd->SCp.buffer->length; 757 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); 758 } else { 759 cmd->SCp.buffer = NULL; 760 cmd->SCp.this_residual = 0; 761 cmd->SCp.ptr = NULL; 762 } 763 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1; 764 cmd->SCp.phase++; 765 766 case 5: /* Phase 5 - Data transfer stage */ 767 w_ctr(ppb, 0x0c); 768 if (!(r_str(ppb) & 0x80)) 769 return 1; 770 771 retv = ppa_completion(cmd); 772 if (retv == -1) 773 return 0; 774 if (retv == 0) 775 return 1; 776 cmd->SCp.phase++; 777 778 case 6: /* Phase 6 - Read status/message */ 779 cmd->result = DID_OK << 16; 780 /* Check for data overrun */ 781 if (ppa_wait(dev) != (unsigned char) 0xf0) { 782 ppa_fail(dev, DID_ERROR); 783 return 0; 784 } 785 if (ppa_in(dev, &l, 1)) { /* read status byte */ 786 /* Check for optional message byte */ 787 if (ppa_wait(dev) == (unsigned char) 0xf0) 788 ppa_in(dev, &h, 1); 789 cmd->result = 790 (DID_OK << 16) + (h << 8) + (l & STATUS_MASK); 791 } 792 return 0; /* Finished */ 793 break; 794 795 default: 796 printk(KERN_ERR "ppa: Invalid scsi phase\n"); 797 } 798 return 0; 799 } 800 801 static int ppa_queuecommand(struct scsi_cmnd *cmd, 802 void (*done) (struct scsi_cmnd *)) 803 { 804 ppa_struct *dev = ppa_dev(cmd->device->host); 805 806 if (dev->cur_cmd) { 807 printk(KERN_ERR "PPA: bug in ppa_queuecommand\n"); 808 return 0; 809 } 810 dev->failed = 0; 811 dev->jstart = jiffies; 812 dev->cur_cmd = cmd; 813 cmd->scsi_done = done; 814 cmd->result = DID_ERROR << 16; /* default return code */ 815 cmd->SCp.phase = 0; /* bus free */ 816 817 schedule_delayed_work(&dev->ppa_tq, 0); 818 819 ppa_pb_claim(dev); 820 821 return 0; 822 } 823 824 /* 825 * Apparently the disk->capacity attribute is off by 1 sector 826 * for all disk drives. We add the one here, but it should really 827 * be done in sd.c. Even if it gets fixed there, this will still 828 * work. 829 */ 830 static int ppa_biosparam(struct scsi_device *sdev, struct block_device *dev, 831 sector_t capacity, int ip[]) 832 { 833 ip[0] = 0x40; 834 ip[1] = 0x20; 835 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]); 836 if (ip[2] > 1024) { 837 ip[0] = 0xff; 838 ip[1] = 0x3f; 839 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]); 840 if (ip[2] > 1023) 841 ip[2] = 1023; 842 } 843 return 0; 844 } 845 846 static int ppa_abort(struct scsi_cmnd *cmd) 847 { 848 ppa_struct *dev = ppa_dev(cmd->device->host); 849 /* 850 * There is no method for aborting commands since Iomega 851 * have tied the SCSI_MESSAGE line high in the interface 852 */ 853 854 switch (cmd->SCp.phase) { 855 case 0: /* Do not have access to parport */ 856 case 1: /* Have not connected to interface */ 857 dev->cur_cmd = NULL; /* Forget the problem */ 858 return SUCCESS; 859 break; 860 default: /* SCSI command sent, can not abort */ 861 return FAILED; 862 break; 863 } 864 } 865 866 static void ppa_reset_pulse(unsigned int base) 867 { 868 w_dtr(base, 0x40); 869 w_ctr(base, 0x8); 870 udelay(30); 871 w_ctr(base, 0xc); 872 } 873 874 static int ppa_reset(struct scsi_cmnd *cmd) 875 { 876 ppa_struct *dev = ppa_dev(cmd->device->host); 877 878 if (cmd->SCp.phase) 879 ppa_disconnect(dev); 880 dev->cur_cmd = NULL; /* Forget the problem */ 881 882 ppa_connect(dev, CONNECT_NORMAL); 883 ppa_reset_pulse(dev->base); 884 mdelay(1); /* device settle delay */ 885 ppa_disconnect(dev); 886 mdelay(1); /* device settle delay */ 887 return SUCCESS; 888 } 889 890 static int device_check(ppa_struct *dev) 891 { 892 /* This routine looks for a device and then attempts to use EPP 893 to send a command. If all goes as planned then EPP is available. */ 894 895 static u8 cmd[6] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 896 int loop, old_mode, status, k, ppb = dev->base; 897 unsigned char l; 898 899 old_mode = dev->mode; 900 for (loop = 0; loop < 8; loop++) { 901 /* Attempt to use EPP for Test Unit Ready */ 902 if ((ppb & 0x0007) == 0x0000) 903 dev->mode = PPA_EPP_32; 904 905 second_pass: 906 ppa_connect(dev, CONNECT_EPP_MAYBE); 907 /* Select SCSI device */ 908 if (!ppa_select(dev, loop)) { 909 ppa_disconnect(dev); 910 continue; 911 } 912 printk(KERN_INFO "ppa: Found device at ID %i, Attempting to use %s\n", 913 loop, PPA_MODE_STRING[dev->mode]); 914 915 /* Send SCSI command */ 916 status = 1; 917 w_ctr(ppb, 0x0c); 918 for (l = 0; (l < 6) && (status); l++) 919 status = ppa_out(dev, cmd, 1); 920 921 if (!status) { 922 ppa_disconnect(dev); 923 ppa_connect(dev, CONNECT_EPP_MAYBE); 924 w_dtr(ppb, 0x40); 925 w_ctr(ppb, 0x08); 926 udelay(30); 927 w_ctr(ppb, 0x0c); 928 udelay(1000); 929 ppa_disconnect(dev); 930 udelay(1000); 931 if (dev->mode == PPA_EPP_32) { 932 dev->mode = old_mode; 933 goto second_pass; 934 } 935 return -EIO; 936 } 937 w_ctr(ppb, 0x0c); 938 k = 1000000; /* 1 Second */ 939 do { 940 l = r_str(ppb); 941 k--; 942 udelay(1); 943 } while (!(l & 0x80) && (k)); 944 945 l &= 0xf0; 946 947 if (l != 0xf0) { 948 ppa_disconnect(dev); 949 ppa_connect(dev, CONNECT_EPP_MAYBE); 950 ppa_reset_pulse(ppb); 951 udelay(1000); 952 ppa_disconnect(dev); 953 udelay(1000); 954 if (dev->mode == PPA_EPP_32) { 955 dev->mode = old_mode; 956 goto second_pass; 957 } 958 return -EIO; 959 } 960 ppa_disconnect(dev); 961 printk(KERN_INFO "ppa: Communication established with ID %i using %s\n", 962 loop, PPA_MODE_STRING[dev->mode]); 963 ppa_connect(dev, CONNECT_EPP_MAYBE); 964 ppa_reset_pulse(ppb); 965 udelay(1000); 966 ppa_disconnect(dev); 967 udelay(1000); 968 return 0; 969 } 970 return -ENODEV; 971 } 972 973 static int ppa_adjust_queue(struct scsi_device *device) 974 { 975 blk_queue_bounce_limit(device->request_queue, BLK_BOUNCE_HIGH); 976 return 0; 977 } 978 979 static struct scsi_host_template ppa_template = { 980 .module = THIS_MODULE, 981 .proc_name = "ppa", 982 .proc_info = ppa_proc_info, 983 .name = "Iomega VPI0 (ppa) interface", 984 .queuecommand = ppa_queuecommand, 985 .eh_abort_handler = ppa_abort, 986 .eh_bus_reset_handler = ppa_reset, 987 .eh_host_reset_handler = ppa_reset, 988 .bios_param = ppa_biosparam, 989 .this_id = -1, 990 .sg_tablesize = SG_ALL, 991 .cmd_per_lun = 1, 992 .use_clustering = ENABLE_CLUSTERING, 993 .can_queue = 1, 994 .slave_alloc = ppa_adjust_queue, 995 }; 996 997 /*************************************************************************** 998 * Parallel port probing routines * 999 ***************************************************************************/ 1000 1001 static LIST_HEAD(ppa_hosts); 1002 1003 static int __ppa_attach(struct parport *pb) 1004 { 1005 struct Scsi_Host *host; 1006 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(waiting); 1007 DEFINE_WAIT(wait); 1008 ppa_struct *dev; 1009 int ports; 1010 int modes, ppb, ppb_hi; 1011 int err = -ENOMEM; 1012 1013 dev = kzalloc(sizeof(ppa_struct), GFP_KERNEL); 1014 if (!dev) 1015 return -ENOMEM; 1016 dev->base = -1; 1017 dev->mode = PPA_AUTODETECT; 1018 dev->recon_tmo = PPA_RECON_TMO; 1019 init_waitqueue_head(&waiting); 1020 dev->dev = parport_register_device(pb, "ppa", NULL, ppa_wakeup, 1021 NULL, 0, dev); 1022 1023 if (!dev->dev) 1024 goto out; 1025 1026 /* Claim the bus so it remembers what we do to the control 1027 * registers. [ CTR and ECP ] 1028 */ 1029 err = -EBUSY; 1030 dev->waiting = &waiting; 1031 prepare_to_wait(&waiting, &wait, TASK_UNINTERRUPTIBLE); 1032 if (ppa_pb_claim(dev)) 1033 schedule_timeout(3 * HZ); 1034 if (dev->wanted) { 1035 printk(KERN_ERR "ppa%d: failed to claim parport because " 1036 "a pardevice is owning the port for too long " 1037 "time!\n", pb->number); 1038 ppa_pb_dismiss(dev); 1039 dev->waiting = NULL; 1040 finish_wait(&waiting, &wait); 1041 goto out1; 1042 } 1043 dev->waiting = NULL; 1044 finish_wait(&waiting, &wait); 1045 ppb = dev->base = dev->dev->port->base; 1046 ppb_hi = dev->dev->port->base_hi; 1047 w_ctr(ppb, 0x0c); 1048 modes = dev->dev->port->modes; 1049 1050 /* Mode detection works up the chain of speed 1051 * This avoids a nasty if-then-else-if-... tree 1052 */ 1053 dev->mode = PPA_NIBBLE; 1054 1055 if (modes & PARPORT_MODE_TRISTATE) 1056 dev->mode = PPA_PS2; 1057 1058 if (modes & PARPORT_MODE_ECP) { 1059 w_ecr(ppb_hi, 0x20); 1060 dev->mode = PPA_PS2; 1061 } 1062 if ((modes & PARPORT_MODE_EPP) && (modes & PARPORT_MODE_ECP)) 1063 w_ecr(ppb_hi, 0x80); 1064 1065 /* Done configuration */ 1066 1067 err = ppa_init(dev); 1068 ppa_pb_release(dev); 1069 1070 if (err) 1071 goto out1; 1072 1073 /* now the glue ... */ 1074 if (dev->mode == PPA_NIBBLE || dev->mode == PPA_PS2) 1075 ports = 3; 1076 else 1077 ports = 8; 1078 1079 INIT_DELAYED_WORK(&dev->ppa_tq, ppa_interrupt); 1080 1081 err = -ENOMEM; 1082 host = scsi_host_alloc(&ppa_template, sizeof(ppa_struct *)); 1083 if (!host) 1084 goto out1; 1085 host->io_port = pb->base; 1086 host->n_io_port = ports; 1087 host->dma_channel = -1; 1088 host->unique_id = pb->number; 1089 *(ppa_struct **)&host->hostdata = dev; 1090 dev->host = host; 1091 list_add_tail(&dev->list, &ppa_hosts); 1092 err = scsi_add_host(host, NULL); 1093 if (err) 1094 goto out2; 1095 scsi_scan_host(host); 1096 return 0; 1097 out2: 1098 list_del_init(&dev->list); 1099 scsi_host_put(host); 1100 out1: 1101 parport_unregister_device(dev->dev); 1102 out: 1103 kfree(dev); 1104 return err; 1105 } 1106 1107 static void ppa_attach(struct parport *pb) 1108 { 1109 __ppa_attach(pb); 1110 } 1111 1112 static void ppa_detach(struct parport *pb) 1113 { 1114 ppa_struct *dev; 1115 list_for_each_entry(dev, &ppa_hosts, list) { 1116 if (dev->dev->port == pb) { 1117 list_del_init(&dev->list); 1118 scsi_remove_host(dev->host); 1119 scsi_host_put(dev->host); 1120 parport_unregister_device(dev->dev); 1121 kfree(dev); 1122 break; 1123 } 1124 } 1125 } 1126 1127 static struct parport_driver ppa_driver = { 1128 .name = "ppa", 1129 .attach = ppa_attach, 1130 .detach = ppa_detach, 1131 }; 1132 1133 static int __init ppa_driver_init(void) 1134 { 1135 printk(KERN_INFO "ppa: Version %s\n", PPA_VERSION); 1136 return parport_register_driver(&ppa_driver); 1137 } 1138 1139 static void __exit ppa_driver_exit(void) 1140 { 1141 parport_unregister_driver(&ppa_driver); 1142 } 1143 1144 module_init(ppa_driver_init); 1145 module_exit(ppa_driver_exit); 1146 MODULE_LICENSE("GPL"); 1147