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 unsigned int dev_no; /* Device number */ 41 wait_queue_head_t *waiting; 42 struct Scsi_Host *host; 43 struct list_head list; 44 } ppa_struct; 45 46 #include "ppa.h" 47 48 static inline ppa_struct *ppa_dev(struct Scsi_Host *host) 49 { 50 return *(ppa_struct **)&host->hostdata; 51 } 52 53 static DEFINE_SPINLOCK(arbitration_lock); 54 55 static void got_it(ppa_struct *dev) 56 { 57 dev->base = dev->dev->port->base; 58 if (dev->cur_cmd) 59 dev->cur_cmd->SCp.phase = 1; 60 else 61 wake_up(dev->waiting); 62 } 63 64 static void ppa_wakeup(void *ref) 65 { 66 ppa_struct *dev = (ppa_struct *) ref; 67 unsigned long flags; 68 69 spin_lock_irqsave(&arbitration_lock, flags); 70 if (dev->wanted) { 71 parport_claim(dev->dev); 72 got_it(dev); 73 dev->wanted = 0; 74 } 75 spin_unlock_irqrestore(&arbitration_lock, flags); 76 return; 77 } 78 79 static int ppa_pb_claim(ppa_struct *dev) 80 { 81 unsigned long flags; 82 int res = 1; 83 spin_lock_irqsave(&arbitration_lock, flags); 84 if (parport_claim(dev->dev) == 0) { 85 got_it(dev); 86 res = 0; 87 } 88 dev->wanted = res; 89 spin_unlock_irqrestore(&arbitration_lock, flags); 90 return res; 91 } 92 93 static void ppa_pb_dismiss(ppa_struct *dev) 94 { 95 unsigned long flags; 96 int wanted; 97 spin_lock_irqsave(&arbitration_lock, flags); 98 wanted = dev->wanted; 99 dev->wanted = 0; 100 spin_unlock_irqrestore(&arbitration_lock, flags); 101 if (!wanted) 102 parport_release(dev->dev); 103 } 104 105 static inline void ppa_pb_release(ppa_struct *dev) 106 { 107 parport_release(dev->dev); 108 } 109 110 /* 111 * Start of Chipset kludges 112 */ 113 114 /* This is to give the ppa driver a way to modify the timings (and other 115 * parameters) by writing to the /proc/scsi/ppa/0 file. 116 * Very simple method really... (To simple, no error checking :( ) 117 * Reason: Kernel hackers HATE having to unload and reload modules for 118 * testing... 119 * Also gives a method to use a script to obtain optimum timings (TODO) 120 */ 121 122 static inline int ppa_write_info(struct Scsi_Host *host, char *buffer, int length) 123 { 124 ppa_struct *dev = ppa_dev(host); 125 unsigned long x; 126 127 if ((length > 5) && (strncmp(buffer, "mode=", 5) == 0)) { 128 x = simple_strtoul(buffer + 5, NULL, 0); 129 dev->mode = x; 130 return length; 131 } 132 if ((length > 10) && (strncmp(buffer, "recon_tmo=", 10) == 0)) { 133 x = simple_strtoul(buffer + 10, NULL, 0); 134 dev->recon_tmo = x; 135 printk(KERN_INFO "ppa: recon_tmo set to %ld\n", x); 136 return length; 137 } 138 printk(KERN_WARNING "ppa /proc: invalid variable\n"); 139 return -EINVAL; 140 } 141 142 static int ppa_show_info(struct seq_file *m, struct Scsi_Host *host) 143 { 144 ppa_struct *dev = ppa_dev(host); 145 146 seq_printf(m, "Version : %s\n", PPA_VERSION); 147 seq_printf(m, "Parport : %s\n", dev->dev->port->name); 148 seq_printf(m, "Mode : %s\n", PPA_MODE_STRING[dev->mode]); 149 #if PPA_DEBUG > 0 150 seq_printf(m, "recon_tmo : %lu\n", dev->recon_tmo); 151 #endif 152 return 0; 153 } 154 155 static int device_check(ppa_struct *dev); 156 157 #if PPA_DEBUG > 0 158 #define ppa_fail(x,y) printk("ppa: ppa_fail(%i) from %s at line %d\n",\ 159 y, __func__, __LINE__); ppa_fail_func(x,y); 160 static inline void ppa_fail_func(ppa_struct *dev, int error_code) 161 #else 162 static inline void ppa_fail(ppa_struct *dev, int error_code) 163 #endif 164 { 165 /* If we fail a device then we trash status / message bytes */ 166 if (dev->cur_cmd) { 167 dev->cur_cmd->result = error_code << 16; 168 dev->failed = 1; 169 } 170 } 171 172 /* 173 * Wait for the high bit to be set. 174 * 175 * In principle, this could be tied to an interrupt, but the adapter 176 * doesn't appear to be designed to support interrupts. We spin on 177 * the 0x80 ready bit. 178 */ 179 static unsigned char ppa_wait(ppa_struct *dev) 180 { 181 int k; 182 unsigned short ppb = dev->base; 183 unsigned char r; 184 185 k = PPA_SPIN_TMO; 186 /* Wait for bit 6 and 7 - PJC */ 187 for (r = r_str(ppb); ((r & 0xc0) != 0xc0) && (k); k--) { 188 udelay(1); 189 r = r_str(ppb); 190 } 191 192 /* 193 * return some status information. 194 * Semantics: 0xc0 = ZIP wants more data 195 * 0xd0 = ZIP wants to send more data 196 * 0xe0 = ZIP is expecting SCSI command data 197 * 0xf0 = end of transfer, ZIP is sending status 198 */ 199 if (k) 200 return (r & 0xf0); 201 202 /* Counter expired - Time out occurred */ 203 ppa_fail(dev, DID_TIME_OUT); 204 printk(KERN_WARNING "ppa timeout in ppa_wait\n"); 205 return 0; /* command timed out */ 206 } 207 208 /* 209 * Clear EPP Timeout Bit 210 */ 211 static inline void epp_reset(unsigned short ppb) 212 { 213 int i; 214 215 i = r_str(ppb); 216 w_str(ppb, i); 217 w_str(ppb, i & 0xfe); 218 } 219 220 /* 221 * Wait for empty ECP fifo (if we are in ECP fifo mode only) 222 */ 223 static inline void ecp_sync(ppa_struct *dev) 224 { 225 int i, ppb_hi = dev->dev->port->base_hi; 226 227 if (ppb_hi == 0) 228 return; 229 230 if ((r_ecr(ppb_hi) & 0xe0) == 0x60) { /* mode 011 == ECP fifo mode */ 231 for (i = 0; i < 100; i++) { 232 if (r_ecr(ppb_hi) & 0x01) 233 return; 234 udelay(5); 235 } 236 printk(KERN_WARNING "ppa: ECP sync failed as data still present in FIFO.\n"); 237 } 238 } 239 240 static int ppa_byte_out(unsigned short base, const char *buffer, int len) 241 { 242 int i; 243 244 for (i = len; i; i--) { 245 w_dtr(base, *buffer++); 246 w_ctr(base, 0xe); 247 w_ctr(base, 0xc); 248 } 249 return 1; /* All went well - we hope! */ 250 } 251 252 static int ppa_byte_in(unsigned short base, char *buffer, int len) 253 { 254 int i; 255 256 for (i = len; i; i--) { 257 *buffer++ = r_dtr(base); 258 w_ctr(base, 0x27); 259 w_ctr(base, 0x25); 260 } 261 return 1; /* All went well - we hope! */ 262 } 263 264 static int ppa_nibble_in(unsigned short base, char *buffer, int len) 265 { 266 for (; len; len--) { 267 unsigned char h; 268 269 w_ctr(base, 0x4); 270 h = r_str(base) & 0xf0; 271 w_ctr(base, 0x6); 272 *buffer++ = h | ((r_str(base) & 0xf0) >> 4); 273 } 274 return 1; /* All went well - we hope! */ 275 } 276 277 static int ppa_out(ppa_struct *dev, char *buffer, int len) 278 { 279 int r; 280 unsigned short ppb = dev->base; 281 282 r = ppa_wait(dev); 283 284 if ((r & 0x50) != 0x40) { 285 ppa_fail(dev, DID_ERROR); 286 return 0; 287 } 288 switch (dev->mode) { 289 case PPA_NIBBLE: 290 case PPA_PS2: 291 /* 8 bit output, with a loop */ 292 r = ppa_byte_out(ppb, buffer, len); 293 break; 294 295 case PPA_EPP_32: 296 case PPA_EPP_16: 297 case PPA_EPP_8: 298 epp_reset(ppb); 299 w_ctr(ppb, 0x4); 300 #ifdef CONFIG_SCSI_IZIP_EPP16 301 if (!(((long) buffer | len) & 0x01)) 302 outsw(ppb + 4, buffer, len >> 1); 303 #else 304 if (!(((long) buffer | len) & 0x03)) 305 outsl(ppb + 4, buffer, len >> 2); 306 #endif 307 else 308 outsb(ppb + 4, buffer, len); 309 w_ctr(ppb, 0xc); 310 r = !(r_str(ppb) & 0x01); 311 w_ctr(ppb, 0xc); 312 ecp_sync(dev); 313 break; 314 315 default: 316 printk(KERN_ERR "PPA: bug in ppa_out()\n"); 317 r = 0; 318 } 319 return r; 320 } 321 322 static int ppa_in(ppa_struct *dev, char *buffer, int len) 323 { 324 int r; 325 unsigned short ppb = dev->base; 326 327 r = ppa_wait(dev); 328 329 if ((r & 0x50) != 0x50) { 330 ppa_fail(dev, DID_ERROR); 331 return 0; 332 } 333 switch (dev->mode) { 334 case PPA_NIBBLE: 335 /* 4 bit input, with a loop */ 336 r = ppa_nibble_in(ppb, buffer, len); 337 w_ctr(ppb, 0xc); 338 break; 339 340 case PPA_PS2: 341 /* 8 bit input, with a loop */ 342 w_ctr(ppb, 0x25); 343 r = ppa_byte_in(ppb, buffer, len); 344 w_ctr(ppb, 0x4); 345 w_ctr(ppb, 0xc); 346 break; 347 348 case PPA_EPP_32: 349 case PPA_EPP_16: 350 case PPA_EPP_8: 351 epp_reset(ppb); 352 w_ctr(ppb, 0x24); 353 #ifdef CONFIG_SCSI_IZIP_EPP16 354 if (!(((long) buffer | len) & 0x01)) 355 insw(ppb + 4, buffer, len >> 1); 356 #else 357 if (!(((long) buffer | len) & 0x03)) 358 insl(ppb + 4, buffer, len >> 2); 359 #endif 360 else 361 insb(ppb + 4, buffer, len); 362 w_ctr(ppb, 0x2c); 363 r = !(r_str(ppb) & 0x01); 364 w_ctr(ppb, 0x2c); 365 ecp_sync(dev); 366 break; 367 368 default: 369 printk(KERN_ERR "PPA: bug in ppa_ins()\n"); 370 r = 0; 371 break; 372 } 373 return r; 374 } 375 376 /* end of ppa_io.h */ 377 static inline void ppa_d_pulse(unsigned short ppb, unsigned char b) 378 { 379 w_dtr(ppb, b); 380 w_ctr(ppb, 0xc); 381 w_ctr(ppb, 0xe); 382 w_ctr(ppb, 0xc); 383 w_ctr(ppb, 0x4); 384 w_ctr(ppb, 0xc); 385 } 386 387 static void ppa_disconnect(ppa_struct *dev) 388 { 389 unsigned short ppb = dev->base; 390 391 ppa_d_pulse(ppb, 0); 392 ppa_d_pulse(ppb, 0x3c); 393 ppa_d_pulse(ppb, 0x20); 394 ppa_d_pulse(ppb, 0xf); 395 } 396 397 static inline void ppa_c_pulse(unsigned short ppb, unsigned char b) 398 { 399 w_dtr(ppb, b); 400 w_ctr(ppb, 0x4); 401 w_ctr(ppb, 0x6); 402 w_ctr(ppb, 0x4); 403 w_ctr(ppb, 0xc); 404 } 405 406 static inline void ppa_connect(ppa_struct *dev, int flag) 407 { 408 unsigned short ppb = dev->base; 409 410 ppa_c_pulse(ppb, 0); 411 ppa_c_pulse(ppb, 0x3c); 412 ppa_c_pulse(ppb, 0x20); 413 if ((flag == CONNECT_EPP_MAYBE) && IN_EPP_MODE(dev->mode)) 414 ppa_c_pulse(ppb, 0xcf); 415 else 416 ppa_c_pulse(ppb, 0x8f); 417 } 418 419 static int ppa_select(ppa_struct *dev, int target) 420 { 421 int k; 422 unsigned short ppb = dev->base; 423 424 /* 425 * Bit 6 (0x40) is the device selected bit. 426 * First we must wait till the current device goes off line... 427 */ 428 k = PPA_SELECT_TMO; 429 do { 430 k--; 431 udelay(1); 432 } while ((r_str(ppb) & 0x40) && (k)); 433 if (!k) 434 return 0; 435 436 w_dtr(ppb, (1 << target)); 437 w_ctr(ppb, 0xe); 438 w_ctr(ppb, 0xc); 439 w_dtr(ppb, 0x80); /* This is NOT the initator */ 440 w_ctr(ppb, 0x8); 441 442 k = PPA_SELECT_TMO; 443 do { 444 k--; 445 udelay(1); 446 } 447 while (!(r_str(ppb) & 0x40) && (k)); 448 if (!k) 449 return 0; 450 451 return 1; 452 } 453 454 /* 455 * This is based on a trace of what the Iomega DOS 'guest' driver does. 456 * I've tried several different kinds of parallel ports with guest and 457 * coded this to react in the same ways that it does. 458 * 459 * The return value from this function is just a hint about where the 460 * handshaking failed. 461 * 462 */ 463 static int ppa_init(ppa_struct *dev) 464 { 465 int retv; 466 unsigned short ppb = dev->base; 467 468 ppa_disconnect(dev); 469 ppa_connect(dev, CONNECT_NORMAL); 470 471 retv = 2; /* Failed */ 472 473 w_ctr(ppb, 0xe); 474 if ((r_str(ppb) & 0x08) == 0x08) 475 retv--; 476 477 w_ctr(ppb, 0xc); 478 if ((r_str(ppb) & 0x08) == 0x00) 479 retv--; 480 481 if (!retv) 482 ppa_reset_pulse(ppb); 483 udelay(1000); /* Allow devices to settle down */ 484 ppa_disconnect(dev); 485 udelay(1000); /* Another delay to allow devices to settle */ 486 487 if (retv) 488 return -EIO; 489 490 return device_check(dev); 491 } 492 493 static inline int ppa_send_command(struct scsi_cmnd *cmd) 494 { 495 ppa_struct *dev = ppa_dev(cmd->device->host); 496 int k; 497 498 w_ctr(dev->base, 0x0c); 499 500 for (k = 0; k < cmd->cmd_len; k++) 501 if (!ppa_out(dev, &cmd->cmnd[k], 1)) 502 return 0; 503 return 1; 504 } 505 506 /* 507 * The bulk flag enables some optimisations in the data transfer loops, 508 * it should be true for any command that transfers data in integral 509 * numbers of sectors. 510 * 511 * The driver appears to remain stable if we speed up the parallel port 512 * i/o in this function, but not elsewhere. 513 */ 514 static int ppa_completion(struct scsi_cmnd *cmd) 515 { 516 /* Return codes: 517 * -1 Error 518 * 0 Told to schedule 519 * 1 Finished data transfer 520 */ 521 ppa_struct *dev = ppa_dev(cmd->device->host); 522 unsigned short ppb = dev->base; 523 unsigned long start_jiffies = jiffies; 524 525 unsigned char r, v; 526 int fast, bulk, status; 527 528 v = cmd->cmnd[0]; 529 bulk = ((v == READ_6) || 530 (v == READ_10) || (v == WRITE_6) || (v == WRITE_10)); 531 532 /* 533 * We only get here if the drive is ready to comunicate, 534 * hence no need for a full ppa_wait. 535 */ 536 r = (r_str(ppb) & 0xf0); 537 538 while (r != (unsigned char) 0xf0) { 539 /* 540 * If we have been running for more than a full timer tick 541 * then take a rest. 542 */ 543 if (time_after(jiffies, start_jiffies + 1)) 544 return 0; 545 546 if ((cmd->SCp.this_residual <= 0)) { 547 ppa_fail(dev, DID_ERROR); 548 return -1; /* ERROR_RETURN */ 549 } 550 551 /* On some hardware we have SCSI disconnected (6th bit low) 552 * for about 100usecs. It is too expensive to wait a 553 * tick on every loop so we busy wait for no more than 554 * 500usecs to give the drive a chance first. We do not 555 * change things for "normal" hardware since generally 556 * the 6th bit is always high. 557 * This makes the CPU load higher on some hardware 558 * but otherwise we can not get more than 50K/secs 559 * on this problem hardware. 560 */ 561 if ((r & 0xc0) != 0xc0) { 562 /* Wait for reconnection should be no more than 563 * jiffy/2 = 5ms = 5000 loops 564 */ 565 unsigned long k = dev->recon_tmo; 566 for (; k && ((r = (r_str(ppb) & 0xf0)) & 0xc0) != 0xc0; 567 k--) 568 udelay(1); 569 570 if (!k) 571 return 0; 572 } 573 574 /* determine if we should use burst I/O */ 575 fast = (bulk && (cmd->SCp.this_residual >= PPA_BURST_SIZE)) 576 ? PPA_BURST_SIZE : 1; 577 578 if (r == (unsigned char) 0xc0) 579 status = ppa_out(dev, cmd->SCp.ptr, fast); 580 else 581 status = ppa_in(dev, cmd->SCp.ptr, fast); 582 583 cmd->SCp.ptr += fast; 584 cmd->SCp.this_residual -= fast; 585 586 if (!status) { 587 ppa_fail(dev, DID_BUS_BUSY); 588 return -1; /* ERROR_RETURN */ 589 } 590 if (cmd->SCp.buffer && !cmd->SCp.this_residual) { 591 /* if scatter/gather, advance to the next segment */ 592 if (cmd->SCp.buffers_residual--) { 593 cmd->SCp.buffer = sg_next(cmd->SCp.buffer); 594 cmd->SCp.this_residual = 595 cmd->SCp.buffer->length; 596 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); 597 } 598 } 599 /* Now check to see if the drive is ready to comunicate */ 600 r = (r_str(ppb) & 0xf0); 601 /* If not, drop back down to the scheduler and wait a timer tick */ 602 if (!(r & 0x80)) 603 return 0; 604 } 605 return 1; /* FINISH_RETURN */ 606 } 607 608 /* 609 * Since the PPA itself doesn't generate interrupts, we use 610 * the scheduler's task queue to generate a stream of call-backs and 611 * complete the request when the drive is ready. 612 */ 613 static void ppa_interrupt(struct work_struct *work) 614 { 615 ppa_struct *dev = container_of(work, ppa_struct, ppa_tq.work); 616 struct scsi_cmnd *cmd = dev->cur_cmd; 617 618 if (!cmd) { 619 printk(KERN_ERR "PPA: bug in ppa_interrupt\n"); 620 return; 621 } 622 if (ppa_engine(dev, cmd)) { 623 schedule_delayed_work(&dev->ppa_tq, 1); 624 return; 625 } 626 /* Command must of completed hence it is safe to let go... */ 627 #if PPA_DEBUG > 0 628 switch ((cmd->result >> 16) & 0xff) { 629 case DID_OK: 630 break; 631 case DID_NO_CONNECT: 632 printk(KERN_DEBUG "ppa: no device at SCSI ID %i\n", cmd->device->target); 633 break; 634 case DID_BUS_BUSY: 635 printk(KERN_DEBUG "ppa: BUS BUSY - EPP timeout detected\n"); 636 break; 637 case DID_TIME_OUT: 638 printk(KERN_DEBUG "ppa: unknown timeout\n"); 639 break; 640 case DID_ABORT: 641 printk(KERN_DEBUG "ppa: told to abort\n"); 642 break; 643 case DID_PARITY: 644 printk(KERN_DEBUG "ppa: parity error (???)\n"); 645 break; 646 case DID_ERROR: 647 printk(KERN_DEBUG "ppa: internal driver error\n"); 648 break; 649 case DID_RESET: 650 printk(KERN_DEBUG "ppa: told to reset device\n"); 651 break; 652 case DID_BAD_INTR: 653 printk(KERN_WARNING "ppa: bad interrupt (???)\n"); 654 break; 655 default: 656 printk(KERN_WARNING "ppa: bad return code (%02x)\n", 657 (cmd->result >> 16) & 0xff); 658 } 659 #endif 660 661 if (cmd->SCp.phase > 1) 662 ppa_disconnect(dev); 663 664 ppa_pb_dismiss(dev); 665 666 dev->cur_cmd = NULL; 667 668 cmd->scsi_done(cmd); 669 } 670 671 static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd) 672 { 673 unsigned short ppb = dev->base; 674 unsigned char l = 0, h = 0; 675 int retv; 676 677 /* First check for any errors that may of occurred 678 * Here we check for internal errors 679 */ 680 if (dev->failed) 681 return 0; 682 683 switch (cmd->SCp.phase) { 684 case 0: /* Phase 0 - Waiting for parport */ 685 if (time_after(jiffies, dev->jstart + HZ)) { 686 /* 687 * We waited more than a second 688 * for parport to call us 689 */ 690 ppa_fail(dev, DID_BUS_BUSY); 691 return 0; 692 } 693 return 1; /* wait until ppa_wakeup claims parport */ 694 case 1: /* Phase 1 - Connected */ 695 { /* Perform a sanity check for cable unplugged */ 696 int retv = 2; /* Failed */ 697 698 ppa_connect(dev, CONNECT_EPP_MAYBE); 699 700 w_ctr(ppb, 0xe); 701 if ((r_str(ppb) & 0x08) == 0x08) 702 retv--; 703 704 w_ctr(ppb, 0xc); 705 if ((r_str(ppb) & 0x08) == 0x00) 706 retv--; 707 708 if (retv) { 709 if (time_after(jiffies, dev->jstart + (1 * HZ))) { 710 printk(KERN_ERR "ppa: Parallel port cable is unplugged.\n"); 711 ppa_fail(dev, DID_BUS_BUSY); 712 return 0; 713 } else { 714 ppa_disconnect(dev); 715 return 1; /* Try again in a jiffy */ 716 } 717 } 718 cmd->SCp.phase++; 719 } 720 fallthrough; 721 722 case 2: /* Phase 2 - We are now talking to the scsi bus */ 723 if (!ppa_select(dev, scmd_id(cmd))) { 724 ppa_fail(dev, DID_NO_CONNECT); 725 return 0; 726 } 727 cmd->SCp.phase++; 728 fallthrough; 729 730 case 3: /* Phase 3 - Ready to accept a command */ 731 w_ctr(ppb, 0x0c); 732 if (!(r_str(ppb) & 0x80)) 733 return 1; 734 735 if (!ppa_send_command(cmd)) 736 return 0; 737 cmd->SCp.phase++; 738 fallthrough; 739 740 case 4: /* Phase 4 - Setup scatter/gather buffers */ 741 if (scsi_bufflen(cmd)) { 742 cmd->SCp.buffer = scsi_sglist(cmd); 743 cmd->SCp.this_residual = cmd->SCp.buffer->length; 744 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); 745 } else { 746 cmd->SCp.buffer = NULL; 747 cmd->SCp.this_residual = 0; 748 cmd->SCp.ptr = NULL; 749 } 750 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1; 751 cmd->SCp.phase++; 752 fallthrough; 753 754 case 5: /* Phase 5 - Data transfer stage */ 755 w_ctr(ppb, 0x0c); 756 if (!(r_str(ppb) & 0x80)) 757 return 1; 758 759 retv = ppa_completion(cmd); 760 if (retv == -1) 761 return 0; 762 if (retv == 0) 763 return 1; 764 cmd->SCp.phase++; 765 fallthrough; 766 767 case 6: /* Phase 6 - Read status/message */ 768 cmd->result = DID_OK << 16; 769 /* Check for data overrun */ 770 if (ppa_wait(dev) != (unsigned char) 0xf0) { 771 ppa_fail(dev, DID_ERROR); 772 return 0; 773 } 774 if (ppa_in(dev, &l, 1)) { /* read status byte */ 775 /* Check for optional message byte */ 776 if (ppa_wait(dev) == (unsigned char) 0xf0) 777 ppa_in(dev, &h, 1); 778 cmd->result = 779 (DID_OK << 16) + (h << 8) + (l & STATUS_MASK); 780 } 781 return 0; /* Finished */ 782 783 default: 784 printk(KERN_ERR "ppa: Invalid scsi phase\n"); 785 } 786 return 0; 787 } 788 789 static int ppa_queuecommand_lck(struct scsi_cmnd *cmd, 790 void (*done) (struct scsi_cmnd *)) 791 { 792 ppa_struct *dev = ppa_dev(cmd->device->host); 793 794 if (dev->cur_cmd) { 795 printk(KERN_ERR "PPA: bug in ppa_queuecommand\n"); 796 return 0; 797 } 798 dev->failed = 0; 799 dev->jstart = jiffies; 800 dev->cur_cmd = cmd; 801 cmd->scsi_done = done; 802 cmd->result = DID_ERROR << 16; /* default return code */ 803 cmd->SCp.phase = 0; /* bus free */ 804 805 schedule_delayed_work(&dev->ppa_tq, 0); 806 807 ppa_pb_claim(dev); 808 809 return 0; 810 } 811 812 static DEF_SCSI_QCMD(ppa_queuecommand) 813 814 /* 815 * Apparently the disk->capacity attribute is off by 1 sector 816 * for all disk drives. We add the one here, but it should really 817 * be done in sd.c. Even if it gets fixed there, this will still 818 * work. 819 */ 820 static int ppa_biosparam(struct scsi_device *sdev, struct block_device *dev, 821 sector_t capacity, int ip[]) 822 { 823 ip[0] = 0x40; 824 ip[1] = 0x20; 825 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]); 826 if (ip[2] > 1024) { 827 ip[0] = 0xff; 828 ip[1] = 0x3f; 829 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]); 830 if (ip[2] > 1023) 831 ip[2] = 1023; 832 } 833 return 0; 834 } 835 836 static int ppa_abort(struct scsi_cmnd *cmd) 837 { 838 ppa_struct *dev = ppa_dev(cmd->device->host); 839 /* 840 * There is no method for aborting commands since Iomega 841 * have tied the SCSI_MESSAGE line high in the interface 842 */ 843 844 switch (cmd->SCp.phase) { 845 case 0: /* Do not have access to parport */ 846 case 1: /* Have not connected to interface */ 847 dev->cur_cmd = NULL; /* Forget the problem */ 848 return SUCCESS; 849 default: /* SCSI command sent, can not abort */ 850 return FAILED; 851 } 852 } 853 854 static void ppa_reset_pulse(unsigned int base) 855 { 856 w_dtr(base, 0x40); 857 w_ctr(base, 0x8); 858 udelay(30); 859 w_ctr(base, 0xc); 860 } 861 862 static int ppa_reset(struct scsi_cmnd *cmd) 863 { 864 ppa_struct *dev = ppa_dev(cmd->device->host); 865 866 if (cmd->SCp.phase) 867 ppa_disconnect(dev); 868 dev->cur_cmd = NULL; /* Forget the problem */ 869 870 ppa_connect(dev, CONNECT_NORMAL); 871 ppa_reset_pulse(dev->base); 872 mdelay(1); /* device settle delay */ 873 ppa_disconnect(dev); 874 mdelay(1); /* device settle delay */ 875 return SUCCESS; 876 } 877 878 static int device_check(ppa_struct *dev) 879 { 880 /* This routine looks for a device and then attempts to use EPP 881 to send a command. If all goes as planned then EPP is available. */ 882 883 static u8 cmd[6] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 884 int loop, old_mode, status, k, ppb = dev->base; 885 unsigned char l; 886 887 old_mode = dev->mode; 888 for (loop = 0; loop < 8; loop++) { 889 /* Attempt to use EPP for Test Unit Ready */ 890 if ((ppb & 0x0007) == 0x0000) 891 dev->mode = PPA_EPP_32; 892 893 second_pass: 894 ppa_connect(dev, CONNECT_EPP_MAYBE); 895 /* Select SCSI device */ 896 if (!ppa_select(dev, loop)) { 897 ppa_disconnect(dev); 898 continue; 899 } 900 printk(KERN_INFO "ppa: Found device at ID %i, Attempting to use %s\n", 901 loop, PPA_MODE_STRING[dev->mode]); 902 903 /* Send SCSI command */ 904 status = 1; 905 w_ctr(ppb, 0x0c); 906 for (l = 0; (l < 6) && (status); l++) 907 status = ppa_out(dev, cmd, 1); 908 909 if (!status) { 910 ppa_disconnect(dev); 911 ppa_connect(dev, CONNECT_EPP_MAYBE); 912 w_dtr(ppb, 0x40); 913 w_ctr(ppb, 0x08); 914 udelay(30); 915 w_ctr(ppb, 0x0c); 916 udelay(1000); 917 ppa_disconnect(dev); 918 udelay(1000); 919 if (dev->mode == PPA_EPP_32) { 920 dev->mode = old_mode; 921 goto second_pass; 922 } 923 return -EIO; 924 } 925 w_ctr(ppb, 0x0c); 926 k = 1000000; /* 1 Second */ 927 do { 928 l = r_str(ppb); 929 k--; 930 udelay(1); 931 } while (!(l & 0x80) && (k)); 932 933 l &= 0xf0; 934 935 if (l != 0xf0) { 936 ppa_disconnect(dev); 937 ppa_connect(dev, CONNECT_EPP_MAYBE); 938 ppa_reset_pulse(ppb); 939 udelay(1000); 940 ppa_disconnect(dev); 941 udelay(1000); 942 if (dev->mode == PPA_EPP_32) { 943 dev->mode = old_mode; 944 goto second_pass; 945 } 946 return -EIO; 947 } 948 ppa_disconnect(dev); 949 printk(KERN_INFO "ppa: Communication established with ID %i using %s\n", 950 loop, PPA_MODE_STRING[dev->mode]); 951 ppa_connect(dev, CONNECT_EPP_MAYBE); 952 ppa_reset_pulse(ppb); 953 udelay(1000); 954 ppa_disconnect(dev); 955 udelay(1000); 956 return 0; 957 } 958 return -ENODEV; 959 } 960 961 static int ppa_adjust_queue(struct scsi_device *device) 962 { 963 blk_queue_bounce_limit(device->request_queue, BLK_BOUNCE_HIGH); 964 return 0; 965 } 966 967 static struct scsi_host_template ppa_template = { 968 .module = THIS_MODULE, 969 .proc_name = "ppa", 970 .show_info = ppa_show_info, 971 .write_info = ppa_write_info, 972 .name = "Iomega VPI0 (ppa) interface", 973 .queuecommand = ppa_queuecommand, 974 .eh_abort_handler = ppa_abort, 975 .eh_host_reset_handler = ppa_reset, 976 .bios_param = ppa_biosparam, 977 .this_id = -1, 978 .sg_tablesize = SG_ALL, 979 .can_queue = 1, 980 .slave_alloc = ppa_adjust_queue, 981 }; 982 983 /*************************************************************************** 984 * Parallel port probing routines * 985 ***************************************************************************/ 986 987 static LIST_HEAD(ppa_hosts); 988 989 /* 990 * Finds the first available device number that can be alloted to the 991 * new ppa device and returns the address of the previous node so that 992 * we can add to the tail and have a list in the ascending order. 993 */ 994 995 static inline ppa_struct *find_parent(void) 996 { 997 ppa_struct *dev, *par = NULL; 998 unsigned int cnt = 0; 999 1000 if (list_empty(&ppa_hosts)) 1001 return NULL; 1002 1003 list_for_each_entry(dev, &ppa_hosts, list) { 1004 if (dev->dev_no != cnt) 1005 return par; 1006 cnt++; 1007 par = dev; 1008 } 1009 1010 return par; 1011 } 1012 1013 static int __ppa_attach(struct parport *pb) 1014 { 1015 struct Scsi_Host *host; 1016 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(waiting); 1017 DEFINE_WAIT(wait); 1018 ppa_struct *dev, *temp; 1019 int ports; 1020 int modes, ppb, ppb_hi; 1021 int err = -ENOMEM; 1022 struct pardev_cb ppa_cb; 1023 1024 dev = kzalloc(sizeof(ppa_struct), GFP_KERNEL); 1025 if (!dev) 1026 return -ENOMEM; 1027 dev->base = -1; 1028 dev->mode = PPA_AUTODETECT; 1029 dev->recon_tmo = PPA_RECON_TMO; 1030 init_waitqueue_head(&waiting); 1031 temp = find_parent(); 1032 if (temp) 1033 dev->dev_no = temp->dev_no + 1; 1034 1035 memset(&ppa_cb, 0, sizeof(ppa_cb)); 1036 ppa_cb.private = dev; 1037 ppa_cb.wakeup = ppa_wakeup; 1038 1039 dev->dev = parport_register_dev_model(pb, "ppa", &ppa_cb, dev->dev_no); 1040 1041 if (!dev->dev) 1042 goto out; 1043 1044 /* Claim the bus so it remembers what we do to the control 1045 * registers. [ CTR and ECP ] 1046 */ 1047 err = -EBUSY; 1048 dev->waiting = &waiting; 1049 prepare_to_wait(&waiting, &wait, TASK_UNINTERRUPTIBLE); 1050 if (ppa_pb_claim(dev)) 1051 schedule_timeout(3 * HZ); 1052 if (dev->wanted) { 1053 printk(KERN_ERR "ppa%d: failed to claim parport because " 1054 "a pardevice is owning the port for too long " 1055 "time!\n", pb->number); 1056 ppa_pb_dismiss(dev); 1057 dev->waiting = NULL; 1058 finish_wait(&waiting, &wait); 1059 goto out1; 1060 } 1061 dev->waiting = NULL; 1062 finish_wait(&waiting, &wait); 1063 ppb = dev->base = dev->dev->port->base; 1064 ppb_hi = dev->dev->port->base_hi; 1065 w_ctr(ppb, 0x0c); 1066 modes = dev->dev->port->modes; 1067 1068 /* Mode detection works up the chain of speed 1069 * This avoids a nasty if-then-else-if-... tree 1070 */ 1071 dev->mode = PPA_NIBBLE; 1072 1073 if (modes & PARPORT_MODE_TRISTATE) 1074 dev->mode = PPA_PS2; 1075 1076 if (modes & PARPORT_MODE_ECP) { 1077 w_ecr(ppb_hi, 0x20); 1078 dev->mode = PPA_PS2; 1079 } 1080 if ((modes & PARPORT_MODE_EPP) && (modes & PARPORT_MODE_ECP)) 1081 w_ecr(ppb_hi, 0x80); 1082 1083 /* Done configuration */ 1084 1085 err = ppa_init(dev); 1086 ppa_pb_release(dev); 1087 1088 if (err) 1089 goto out1; 1090 1091 /* now the glue ... */ 1092 if (dev->mode == PPA_NIBBLE || dev->mode == PPA_PS2) 1093 ports = 3; 1094 else 1095 ports = 8; 1096 1097 INIT_DELAYED_WORK(&dev->ppa_tq, ppa_interrupt); 1098 1099 err = -ENOMEM; 1100 host = scsi_host_alloc(&ppa_template, sizeof(ppa_struct *)); 1101 if (!host) 1102 goto out1; 1103 host->io_port = pb->base; 1104 host->n_io_port = ports; 1105 host->dma_channel = -1; 1106 host->unique_id = pb->number; 1107 *(ppa_struct **)&host->hostdata = dev; 1108 dev->host = host; 1109 list_add_tail(&dev->list, &ppa_hosts); 1110 err = scsi_add_host(host, NULL); 1111 if (err) 1112 goto out2; 1113 scsi_scan_host(host); 1114 return 0; 1115 out2: 1116 list_del_init(&dev->list); 1117 scsi_host_put(host); 1118 out1: 1119 parport_unregister_device(dev->dev); 1120 out: 1121 kfree(dev); 1122 return err; 1123 } 1124 1125 static void ppa_attach(struct parport *pb) 1126 { 1127 __ppa_attach(pb); 1128 } 1129 1130 static void ppa_detach(struct parport *pb) 1131 { 1132 ppa_struct *dev; 1133 list_for_each_entry(dev, &ppa_hosts, list) { 1134 if (dev->dev->port == pb) { 1135 list_del_init(&dev->list); 1136 scsi_remove_host(dev->host); 1137 scsi_host_put(dev->host); 1138 parport_unregister_device(dev->dev); 1139 kfree(dev); 1140 break; 1141 } 1142 } 1143 } 1144 1145 static struct parport_driver ppa_driver = { 1146 .name = "ppa", 1147 .match_port = ppa_attach, 1148 .detach = ppa_detach, 1149 .devmodel = true, 1150 }; 1151 1152 static int __init ppa_driver_init(void) 1153 { 1154 printk(KERN_INFO "ppa: Version %s\n", PPA_VERSION); 1155 return parport_register_driver(&ppa_driver); 1156 } 1157 1158 static void __exit ppa_driver_exit(void) 1159 { 1160 parport_unregister_driver(&ppa_driver); 1161 } 1162 1163 module_init(ppa_driver_init); 1164 module_exit(ppa_driver_exit); 1165 MODULE_LICENSE("GPL"); 1166