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