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 unsigned int mode = PPA_AUTODETECT; 49 module_param(mode, uint, 0644); 50 MODULE_PARM_DESC(mode, "Transfer mode (0 = Autodetect, 1 = SPP 4-bit, " 51 "2 = SPP 8-bit, 3 = EPP 8-bit, 4 = EPP 16-bit, 5 = EPP 32-bit"); 52 53 static struct scsi_pointer *ppa_scsi_pointer(struct scsi_cmnd *cmd) 54 { 55 return scsi_cmd_priv(cmd); 56 } 57 58 static inline ppa_struct *ppa_dev(struct Scsi_Host *host) 59 { 60 return *(ppa_struct **)&host->hostdata; 61 } 62 63 static DEFINE_SPINLOCK(arbitration_lock); 64 65 static void got_it(ppa_struct *dev) 66 { 67 dev->base = dev->dev->port->base; 68 if (dev->cur_cmd) 69 ppa_scsi_pointer(dev->cur_cmd)->phase = 1; 70 else 71 wake_up(dev->waiting); 72 } 73 74 static void ppa_wakeup(void *ref) 75 { 76 ppa_struct *dev = (ppa_struct *) ref; 77 unsigned long flags; 78 79 spin_lock_irqsave(&arbitration_lock, flags); 80 if (dev->wanted) { 81 parport_claim(dev->dev); 82 got_it(dev); 83 dev->wanted = 0; 84 } 85 spin_unlock_irqrestore(&arbitration_lock, flags); 86 return; 87 } 88 89 static int ppa_pb_claim(ppa_struct *dev) 90 { 91 unsigned long flags; 92 int res = 1; 93 spin_lock_irqsave(&arbitration_lock, flags); 94 if (parport_claim(dev->dev) == 0) { 95 got_it(dev); 96 res = 0; 97 } 98 dev->wanted = res; 99 spin_unlock_irqrestore(&arbitration_lock, flags); 100 return res; 101 } 102 103 static void ppa_pb_dismiss(ppa_struct *dev) 104 { 105 unsigned long flags; 106 int wanted; 107 spin_lock_irqsave(&arbitration_lock, flags); 108 wanted = dev->wanted; 109 dev->wanted = 0; 110 spin_unlock_irqrestore(&arbitration_lock, flags); 111 if (!wanted) 112 parport_release(dev->dev); 113 } 114 115 static inline void ppa_pb_release(ppa_struct *dev) 116 { 117 parport_release(dev->dev); 118 } 119 120 /* 121 * Start of Chipset kludges 122 */ 123 124 /* This is to give the ppa driver a way to modify the timings (and other 125 * parameters) by writing to the /proc/scsi/ppa/0 file. 126 * Very simple method really... (To simple, no error checking :( ) 127 * Reason: Kernel hackers HATE having to unload and reload modules for 128 * testing... 129 * Also gives a method to use a script to obtain optimum timings (TODO) 130 */ 131 132 static inline int ppa_write_info(struct Scsi_Host *host, char *buffer, int length) 133 { 134 ppa_struct *dev = ppa_dev(host); 135 unsigned long x; 136 137 if ((length > 5) && (strncmp(buffer, "mode=", 5) == 0)) { 138 x = simple_strtoul(buffer + 5, NULL, 0); 139 dev->mode = x; 140 return length; 141 } 142 if ((length > 10) && (strncmp(buffer, "recon_tmo=", 10) == 0)) { 143 x = simple_strtoul(buffer + 10, NULL, 0); 144 dev->recon_tmo = x; 145 printk(KERN_INFO "ppa: recon_tmo set to %ld\n", x); 146 return length; 147 } 148 printk(KERN_WARNING "ppa /proc: invalid variable\n"); 149 return -EINVAL; 150 } 151 152 static int ppa_show_info(struct seq_file *m, struct Scsi_Host *host) 153 { 154 ppa_struct *dev = ppa_dev(host); 155 156 seq_printf(m, "Version : %s\n", PPA_VERSION); 157 seq_printf(m, "Parport : %s\n", dev->dev->port->name); 158 seq_printf(m, "Mode : %s\n", PPA_MODE_STRING[dev->mode]); 159 #if PPA_DEBUG > 0 160 seq_printf(m, "recon_tmo : %lu\n", dev->recon_tmo); 161 #endif 162 return 0; 163 } 164 165 static int device_check(ppa_struct *dev, bool autodetect); 166 167 #if PPA_DEBUG > 0 168 #define ppa_fail(x,y) printk("ppa: ppa_fail(%i) from %s at line %d\n",\ 169 y, __func__, __LINE__); ppa_fail_func(x,y); 170 static inline void ppa_fail_func(ppa_struct *dev, int error_code) 171 #else 172 static inline void ppa_fail(ppa_struct *dev, int error_code) 173 #endif 174 { 175 /* If we fail a device then we trash status / message bytes */ 176 if (dev->cur_cmd) { 177 dev->cur_cmd->result = error_code << 16; 178 dev->failed = 1; 179 } 180 } 181 182 /* 183 * Wait for the high bit to be set. 184 * 185 * In principle, this could be tied to an interrupt, but the adapter 186 * doesn't appear to be designed to support interrupts. We spin on 187 * the 0x80 ready bit. 188 */ 189 static unsigned char ppa_wait(ppa_struct *dev) 190 { 191 int k; 192 unsigned short ppb = dev->base; 193 unsigned char r; 194 195 k = PPA_SPIN_TMO; 196 /* Wait for bit 6 and 7 - PJC */ 197 for (r = r_str(ppb); ((r & 0xc0) != 0xc0) && (k); k--) { 198 udelay(1); 199 r = r_str(ppb); 200 } 201 202 /* 203 * return some status information. 204 * Semantics: 0xc0 = ZIP wants more data 205 * 0xd0 = ZIP wants to send more data 206 * 0xe0 = ZIP is expecting SCSI command data 207 * 0xf0 = end of transfer, ZIP is sending status 208 */ 209 if (k) 210 return (r & 0xf0); 211 212 /* Counter expired - Time out occurred */ 213 ppa_fail(dev, DID_TIME_OUT); 214 printk(KERN_WARNING "ppa timeout in ppa_wait\n"); 215 return 0; /* command timed out */ 216 } 217 218 /* 219 * Clear EPP Timeout Bit 220 */ 221 static inline void epp_reset(unsigned short ppb) 222 { 223 int i; 224 225 i = r_str(ppb); 226 w_str(ppb, i); 227 w_str(ppb, i & 0xfe); 228 } 229 230 /* 231 * Wait for empty ECP fifo (if we are in ECP fifo mode only) 232 */ 233 static inline void ecp_sync(ppa_struct *dev) 234 { 235 int i, ppb_hi = dev->dev->port->base_hi; 236 237 if (ppb_hi == 0) 238 return; 239 240 if ((r_ecr(ppb_hi) & 0xe0) == 0x60) { /* mode 011 == ECP fifo mode */ 241 for (i = 0; i < 100; i++) { 242 if (r_ecr(ppb_hi) & 0x01) 243 return; 244 udelay(5); 245 } 246 printk(KERN_WARNING "ppa: ECP sync failed as data still present in FIFO.\n"); 247 } 248 } 249 250 static int ppa_byte_out(unsigned short base, const char *buffer, int len) 251 { 252 int i; 253 254 for (i = len; i; i--) { 255 w_dtr(base, *buffer++); 256 w_ctr(base, 0xe); 257 w_ctr(base, 0xc); 258 } 259 return 1; /* All went well - we hope! */ 260 } 261 262 static int ppa_byte_in(unsigned short base, char *buffer, int len) 263 { 264 int i; 265 266 for (i = len; i; i--) { 267 *buffer++ = r_dtr(base); 268 w_ctr(base, 0x27); 269 w_ctr(base, 0x25); 270 } 271 return 1; /* All went well - we hope! */ 272 } 273 274 static int ppa_nibble_in(unsigned short base, char *buffer, int len) 275 { 276 for (; len; len--) { 277 unsigned char h; 278 279 w_ctr(base, 0x4); 280 h = r_str(base) & 0xf0; 281 w_ctr(base, 0x6); 282 *buffer++ = h | ((r_str(base) & 0xf0) >> 4); 283 } 284 return 1; /* All went well - we hope! */ 285 } 286 287 static int ppa_out(ppa_struct *dev, char *buffer, int len) 288 { 289 int r; 290 unsigned short ppb = dev->base; 291 292 r = ppa_wait(dev); 293 294 if ((r & 0x50) != 0x40) { 295 ppa_fail(dev, DID_ERROR); 296 return 0; 297 } 298 switch (dev->mode) { 299 case PPA_NIBBLE: 300 case PPA_PS2: 301 /* 8 bit output, with a loop */ 302 r = ppa_byte_out(ppb, buffer, len); 303 break; 304 305 case PPA_EPP_32: 306 case PPA_EPP_16: 307 case PPA_EPP_8: 308 epp_reset(ppb); 309 w_ctr(ppb, 0x4); 310 if (dev->mode == PPA_EPP_32 && !(((long) buffer | len) & 0x03)) 311 outsl(ppb + 4, buffer, len >> 2); 312 else if (dev->mode == PPA_EPP_16 && !(((long) buffer | len) & 0x01)) 313 outsw(ppb + 4, buffer, len >> 1); 314 else 315 outsb(ppb + 4, buffer, len); 316 w_ctr(ppb, 0xc); 317 r = !(r_str(ppb) & 0x01); 318 w_ctr(ppb, 0xc); 319 ecp_sync(dev); 320 break; 321 322 default: 323 printk(KERN_ERR "PPA: bug in ppa_out()\n"); 324 r = 0; 325 } 326 return r; 327 } 328 329 static int ppa_in(ppa_struct *dev, char *buffer, int len) 330 { 331 int r; 332 unsigned short ppb = dev->base; 333 334 r = ppa_wait(dev); 335 336 if ((r & 0x50) != 0x50) { 337 ppa_fail(dev, DID_ERROR); 338 return 0; 339 } 340 switch (dev->mode) { 341 case PPA_NIBBLE: 342 /* 4 bit input, with a loop */ 343 r = ppa_nibble_in(ppb, buffer, len); 344 w_ctr(ppb, 0xc); 345 break; 346 347 case PPA_PS2: 348 /* 8 bit input, with a loop */ 349 w_ctr(ppb, 0x25); 350 r = ppa_byte_in(ppb, buffer, len); 351 w_ctr(ppb, 0x4); 352 w_ctr(ppb, 0xc); 353 break; 354 355 case PPA_EPP_32: 356 case PPA_EPP_16: 357 case PPA_EPP_8: 358 epp_reset(ppb); 359 w_ctr(ppb, 0x24); 360 if (dev->mode == PPA_EPP_32 && !(((long) buffer | len) & 0x03)) 361 insl(ppb + 4, buffer, len >> 2); 362 else if (dev->mode == PPA_EPP_16 && !(((long) buffer | len) & 0x01)) 363 insw(ppb + 4, buffer, len >> 1); 364 else 365 insb(ppb + 4, buffer, len); 366 w_ctr(ppb, 0x2c); 367 r = !(r_str(ppb) & 0x01); 368 w_ctr(ppb, 0x2c); 369 ecp_sync(dev); 370 break; 371 372 default: 373 printk(KERN_ERR "PPA: bug in ppa_ins()\n"); 374 r = 0; 375 break; 376 } 377 return r; 378 } 379 380 /* end of ppa_io.h */ 381 static inline void ppa_d_pulse(unsigned short ppb, unsigned char b) 382 { 383 w_dtr(ppb, b); 384 w_ctr(ppb, 0xc); 385 w_ctr(ppb, 0xe); 386 w_ctr(ppb, 0xc); 387 w_ctr(ppb, 0x4); 388 w_ctr(ppb, 0xc); 389 } 390 391 static void ppa_disconnect(ppa_struct *dev) 392 { 393 unsigned short ppb = dev->base; 394 395 ppa_d_pulse(ppb, 0); 396 ppa_d_pulse(ppb, 0x3c); 397 ppa_d_pulse(ppb, 0x20); 398 ppa_d_pulse(ppb, 0xf); 399 } 400 401 static inline void ppa_c_pulse(unsigned short ppb, unsigned char b) 402 { 403 w_dtr(ppb, b); 404 w_ctr(ppb, 0x4); 405 w_ctr(ppb, 0x6); 406 w_ctr(ppb, 0x4); 407 w_ctr(ppb, 0xc); 408 } 409 410 static inline void ppa_connect(ppa_struct *dev, int flag) 411 { 412 unsigned short ppb = dev->base; 413 414 ppa_c_pulse(ppb, 0); 415 ppa_c_pulse(ppb, 0x3c); 416 ppa_c_pulse(ppb, 0x20); 417 if ((flag == CONNECT_EPP_MAYBE) && IN_EPP_MODE(dev->mode)) 418 ppa_c_pulse(ppb, 0xcf); 419 else 420 ppa_c_pulse(ppb, 0x8f); 421 } 422 423 static int ppa_select(ppa_struct *dev, int target) 424 { 425 int k; 426 unsigned short ppb = dev->base; 427 428 /* 429 * Bit 6 (0x40) is the device selected bit. 430 * First we must wait till the current device goes off line... 431 */ 432 k = PPA_SELECT_TMO; 433 do { 434 k--; 435 udelay(1); 436 } while ((r_str(ppb) & 0x40) && (k)); 437 if (!k) 438 return 0; 439 440 w_dtr(ppb, (1 << target)); 441 w_ctr(ppb, 0xe); 442 w_ctr(ppb, 0xc); 443 w_dtr(ppb, 0x80); /* This is NOT the initator */ 444 w_ctr(ppb, 0x8); 445 446 k = PPA_SELECT_TMO; 447 do { 448 k--; 449 udelay(1); 450 } 451 while (!(r_str(ppb) & 0x40) && (k)); 452 if (!k) 453 return 0; 454 455 return 1; 456 } 457 458 /* 459 * This is based on a trace of what the Iomega DOS 'guest' driver does. 460 * I've tried several different kinds of parallel ports with guest and 461 * coded this to react in the same ways that it does. 462 * 463 * The return value from this function is just a hint about where the 464 * handshaking failed. 465 * 466 */ 467 static int ppa_init(ppa_struct *dev) 468 { 469 int retv; 470 unsigned short ppb = dev->base; 471 bool autodetect = dev->mode == PPA_AUTODETECT; 472 473 if (autodetect) { 474 int modes = dev->dev->port->modes; 475 int ppb_hi = dev->dev->port->base_hi; 476 477 /* Mode detection works up the chain of speed 478 * This avoids a nasty if-then-else-if-... tree 479 */ 480 dev->mode = PPA_NIBBLE; 481 482 if (modes & PARPORT_MODE_TRISTATE) 483 dev->mode = PPA_PS2; 484 485 if (modes & PARPORT_MODE_ECP) { 486 w_ecr(ppb_hi, 0x20); 487 dev->mode = PPA_PS2; 488 } 489 if ((modes & PARPORT_MODE_EPP) && (modes & PARPORT_MODE_ECP)) 490 w_ecr(ppb_hi, 0x80); 491 } 492 493 ppa_disconnect(dev); 494 ppa_connect(dev, CONNECT_NORMAL); 495 496 retv = 2; /* Failed */ 497 498 w_ctr(ppb, 0xe); 499 if ((r_str(ppb) & 0x08) == 0x08) 500 retv--; 501 502 w_ctr(ppb, 0xc); 503 if ((r_str(ppb) & 0x08) == 0x00) 504 retv--; 505 506 if (!retv) 507 ppa_reset_pulse(ppb); 508 udelay(1000); /* Allow devices to settle down */ 509 ppa_disconnect(dev); 510 udelay(1000); /* Another delay to allow devices to settle */ 511 512 if (retv) 513 return -EIO; 514 515 return device_check(dev, autodetect); 516 } 517 518 static inline int ppa_send_command(struct scsi_cmnd *cmd) 519 { 520 ppa_struct *dev = ppa_dev(cmd->device->host); 521 int k; 522 523 w_ctr(dev->base, 0x0c); 524 525 for (k = 0; k < cmd->cmd_len; k++) 526 if (!ppa_out(dev, &cmd->cmnd[k], 1)) 527 return 0; 528 return 1; 529 } 530 531 /* 532 * The bulk flag enables some optimisations in the data transfer loops, 533 * it should be true for any command that transfers data in integral 534 * numbers of sectors. 535 * 536 * The driver appears to remain stable if we speed up the parallel port 537 * i/o in this function, but not elsewhere. 538 */ 539 static int ppa_completion(struct scsi_cmnd *const cmd) 540 { 541 /* Return codes: 542 * -1 Error 543 * 0 Told to schedule 544 * 1 Finished data transfer 545 */ 546 struct scsi_pointer *scsi_pointer = ppa_scsi_pointer(cmd); 547 ppa_struct *dev = ppa_dev(cmd->device->host); 548 unsigned short ppb = dev->base; 549 unsigned long start_jiffies = jiffies; 550 551 unsigned char r, v; 552 int fast, bulk, status; 553 554 v = cmd->cmnd[0]; 555 bulk = ((v == READ_6) || 556 (v == READ_10) || (v == WRITE_6) || (v == WRITE_10)); 557 558 /* 559 * We only get here if the drive is ready to comunicate, 560 * hence no need for a full ppa_wait. 561 */ 562 r = (r_str(ppb) & 0xf0); 563 564 while (r != (unsigned char) 0xf0) { 565 /* 566 * If we have been running for more than a full timer tick 567 * then take a rest. 568 */ 569 if (time_after(jiffies, start_jiffies + 1)) 570 return 0; 571 572 if (scsi_pointer->this_residual <= 0) { 573 ppa_fail(dev, DID_ERROR); 574 return -1; /* ERROR_RETURN */ 575 } 576 577 /* On some hardware we have SCSI disconnected (6th bit low) 578 * for about 100usecs. It is too expensive to wait a 579 * tick on every loop so we busy wait for no more than 580 * 500usecs to give the drive a chance first. We do not 581 * change things for "normal" hardware since generally 582 * the 6th bit is always high. 583 * This makes the CPU load higher on some hardware 584 * but otherwise we can not get more than 50K/secs 585 * on this problem hardware. 586 */ 587 if ((r & 0xc0) != 0xc0) { 588 /* Wait for reconnection should be no more than 589 * jiffy/2 = 5ms = 5000 loops 590 */ 591 unsigned long k = dev->recon_tmo; 592 for (; k && ((r = (r_str(ppb) & 0xf0)) & 0xc0) != 0xc0; 593 k--) 594 udelay(1); 595 596 if (!k) 597 return 0; 598 } 599 600 /* determine if we should use burst I/O */ 601 fast = bulk && scsi_pointer->this_residual >= PPA_BURST_SIZE ? 602 PPA_BURST_SIZE : 1; 603 604 if (r == (unsigned char) 0xc0) 605 status = ppa_out(dev, scsi_pointer->ptr, fast); 606 else 607 status = ppa_in(dev, scsi_pointer->ptr, fast); 608 609 scsi_pointer->ptr += fast; 610 scsi_pointer->this_residual -= fast; 611 612 if (!status) { 613 ppa_fail(dev, DID_BUS_BUSY); 614 return -1; /* ERROR_RETURN */ 615 } 616 if (scsi_pointer->buffer && !scsi_pointer->this_residual) { 617 /* if scatter/gather, advance to the next segment */ 618 if (scsi_pointer->buffers_residual--) { 619 scsi_pointer->buffer = 620 sg_next(scsi_pointer->buffer); 621 scsi_pointer->this_residual = 622 scsi_pointer->buffer->length; 623 scsi_pointer->ptr = 624 sg_virt(scsi_pointer->buffer); 625 } 626 } 627 /* Now check to see if the drive is ready to comunicate */ 628 r = (r_str(ppb) & 0xf0); 629 /* If not, drop back down to the scheduler and wait a timer tick */ 630 if (!(r & 0x80)) 631 return 0; 632 } 633 return 1; /* FINISH_RETURN */ 634 } 635 636 /* 637 * Since the PPA itself doesn't generate interrupts, we use 638 * the scheduler's task queue to generate a stream of call-backs and 639 * complete the request when the drive is ready. 640 */ 641 static void ppa_interrupt(struct work_struct *work) 642 { 643 ppa_struct *dev = container_of(work, ppa_struct, ppa_tq.work); 644 struct scsi_cmnd *cmd = dev->cur_cmd; 645 646 if (!cmd) { 647 printk(KERN_ERR "PPA: bug in ppa_interrupt\n"); 648 return; 649 } 650 if (ppa_engine(dev, cmd)) { 651 schedule_delayed_work(&dev->ppa_tq, 1); 652 return; 653 } 654 /* Command must of completed hence it is safe to let go... */ 655 #if PPA_DEBUG > 0 656 switch ((cmd->result >> 16) & 0xff) { 657 case DID_OK: 658 break; 659 case DID_NO_CONNECT: 660 printk(KERN_DEBUG "ppa: no device at SCSI ID %i\n", scmd_id(cmd)); 661 break; 662 case DID_BUS_BUSY: 663 printk(KERN_DEBUG "ppa: BUS BUSY - EPP timeout detected\n"); 664 break; 665 case DID_TIME_OUT: 666 printk(KERN_DEBUG "ppa: unknown timeout\n"); 667 break; 668 case DID_ABORT: 669 printk(KERN_DEBUG "ppa: told to abort\n"); 670 break; 671 case DID_PARITY: 672 printk(KERN_DEBUG "ppa: parity error (???)\n"); 673 break; 674 case DID_ERROR: 675 printk(KERN_DEBUG "ppa: internal driver error\n"); 676 break; 677 case DID_RESET: 678 printk(KERN_DEBUG "ppa: told to reset device\n"); 679 break; 680 case DID_BAD_INTR: 681 printk(KERN_WARNING "ppa: bad interrupt (???)\n"); 682 break; 683 default: 684 printk(KERN_WARNING "ppa: bad return code (%02x)\n", 685 (cmd->result >> 16) & 0xff); 686 } 687 #endif 688 689 if (ppa_scsi_pointer(cmd)->phase > 1) 690 ppa_disconnect(dev); 691 692 ppa_pb_dismiss(dev); 693 694 dev->cur_cmd = NULL; 695 696 scsi_done(cmd); 697 } 698 699 static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd) 700 { 701 struct scsi_pointer *scsi_pointer = ppa_scsi_pointer(cmd); 702 unsigned short ppb = dev->base; 703 unsigned char l = 0, h = 0; 704 int retv; 705 706 /* First check for any errors that may of occurred 707 * Here we check for internal errors 708 */ 709 if (dev->failed) 710 return 0; 711 712 switch (scsi_pointer->phase) { 713 case 0: /* Phase 0 - Waiting for parport */ 714 if (time_after(jiffies, dev->jstart + HZ)) { 715 /* 716 * We waited more than a second 717 * for parport to call us 718 */ 719 ppa_fail(dev, DID_BUS_BUSY); 720 return 0; 721 } 722 return 1; /* wait until ppa_wakeup claims parport */ 723 case 1: /* Phase 1 - Connected */ 724 { /* Perform a sanity check for cable unplugged */ 725 int retv = 2; /* Failed */ 726 727 ppa_connect(dev, CONNECT_EPP_MAYBE); 728 729 w_ctr(ppb, 0xe); 730 if ((r_str(ppb) & 0x08) == 0x08) 731 retv--; 732 733 w_ctr(ppb, 0xc); 734 if ((r_str(ppb) & 0x08) == 0x00) 735 retv--; 736 737 if (retv) { 738 if (time_after(jiffies, dev->jstart + (1 * HZ))) { 739 printk(KERN_ERR "ppa: Parallel port cable is unplugged.\n"); 740 ppa_fail(dev, DID_BUS_BUSY); 741 return 0; 742 } else { 743 ppa_disconnect(dev); 744 return 1; /* Try again in a jiffy */ 745 } 746 } 747 scsi_pointer->phase++; 748 } 749 fallthrough; 750 751 case 2: /* Phase 2 - We are now talking to the scsi bus */ 752 if (!ppa_select(dev, scmd_id(cmd))) { 753 ppa_fail(dev, DID_NO_CONNECT); 754 return 0; 755 } 756 scsi_pointer->phase++; 757 fallthrough; 758 759 case 3: /* Phase 3 - Ready to accept a command */ 760 w_ctr(ppb, 0x0c); 761 if (!(r_str(ppb) & 0x80)) 762 return 1; 763 764 if (!ppa_send_command(cmd)) 765 return 0; 766 scsi_pointer->phase++; 767 fallthrough; 768 769 case 4: /* Phase 4 - Setup scatter/gather buffers */ 770 if (scsi_bufflen(cmd)) { 771 scsi_pointer->buffer = scsi_sglist(cmd); 772 scsi_pointer->this_residual = 773 scsi_pointer->buffer->length; 774 scsi_pointer->ptr = sg_virt(scsi_pointer->buffer); 775 } else { 776 scsi_pointer->buffer = NULL; 777 scsi_pointer->this_residual = 0; 778 scsi_pointer->ptr = NULL; 779 } 780 scsi_pointer->buffers_residual = scsi_sg_count(cmd) - 1; 781 scsi_pointer->phase++; 782 fallthrough; 783 784 case 5: /* Phase 5 - Data transfer stage */ 785 w_ctr(ppb, 0x0c); 786 if (!(r_str(ppb) & 0x80)) 787 return 1; 788 789 retv = ppa_completion(cmd); 790 if (retv == -1) 791 return 0; 792 if (retv == 0) 793 return 1; 794 scsi_pointer->phase++; 795 fallthrough; 796 797 case 6: /* Phase 6 - Read status/message */ 798 cmd->result = DID_OK << 16; 799 /* Check for data overrun */ 800 if (ppa_wait(dev) != (unsigned char) 0xf0) { 801 ppa_fail(dev, DID_ERROR); 802 return 0; 803 } 804 if (ppa_in(dev, &l, 1)) { /* read status byte */ 805 /* Check for optional message byte */ 806 if (ppa_wait(dev) == (unsigned char) 0xf0) 807 ppa_in(dev, &h, 1); 808 cmd->result = 809 (DID_OK << 16) + (h << 8) + (l & STATUS_MASK); 810 } 811 return 0; /* Finished */ 812 813 default: 814 printk(KERN_ERR "ppa: Invalid scsi phase\n"); 815 } 816 return 0; 817 } 818 819 static int ppa_queuecommand_lck(struct scsi_cmnd *cmd) 820 { 821 ppa_struct *dev = ppa_dev(cmd->device->host); 822 823 if (dev->cur_cmd) { 824 printk(KERN_ERR "PPA: bug in ppa_queuecommand\n"); 825 return 0; 826 } 827 dev->failed = 0; 828 dev->jstart = jiffies; 829 dev->cur_cmd = cmd; 830 cmd->result = DID_ERROR << 16; /* default return code */ 831 ppa_scsi_pointer(cmd)->phase = 0; /* bus free */ 832 833 schedule_delayed_work(&dev->ppa_tq, 0); 834 835 ppa_pb_claim(dev); 836 837 return 0; 838 } 839 840 static DEF_SCSI_QCMD(ppa_queuecommand) 841 842 /* 843 * Apparently the disk->capacity attribute is off by 1 sector 844 * for all disk drives. We add the one here, but it should really 845 * be done in sd.c. Even if it gets fixed there, this will still 846 * work. 847 */ 848 static int ppa_biosparam(struct scsi_device *sdev, struct block_device *dev, 849 sector_t capacity, int ip[]) 850 { 851 ip[0] = 0x40; 852 ip[1] = 0x20; 853 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]); 854 if (ip[2] > 1024) { 855 ip[0] = 0xff; 856 ip[1] = 0x3f; 857 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]); 858 if (ip[2] > 1023) 859 ip[2] = 1023; 860 } 861 return 0; 862 } 863 864 static int ppa_abort(struct scsi_cmnd *cmd) 865 { 866 ppa_struct *dev = ppa_dev(cmd->device->host); 867 /* 868 * There is no method for aborting commands since Iomega 869 * have tied the SCSI_MESSAGE line high in the interface 870 */ 871 872 switch (ppa_scsi_pointer(cmd)->phase) { 873 case 0: /* Do not have access to parport */ 874 case 1: /* Have not connected to interface */ 875 dev->cur_cmd = NULL; /* Forget the problem */ 876 return SUCCESS; 877 default: /* SCSI command sent, can not abort */ 878 return FAILED; 879 } 880 } 881 882 static void ppa_reset_pulse(unsigned int base) 883 { 884 w_dtr(base, 0x40); 885 w_ctr(base, 0x8); 886 udelay(30); 887 w_ctr(base, 0xc); 888 } 889 890 static int ppa_reset(struct scsi_cmnd *cmd) 891 { 892 ppa_struct *dev = ppa_dev(cmd->device->host); 893 894 if (ppa_scsi_pointer(cmd)->phase) 895 ppa_disconnect(dev); 896 dev->cur_cmd = NULL; /* Forget the problem */ 897 898 ppa_connect(dev, CONNECT_NORMAL); 899 ppa_reset_pulse(dev->base); 900 mdelay(1); /* device settle delay */ 901 ppa_disconnect(dev); 902 mdelay(1); /* device settle delay */ 903 return SUCCESS; 904 } 905 906 static int device_check(ppa_struct *dev, bool autodetect) 907 { 908 /* This routine looks for a device and then attempts to use EPP 909 to send a command. If all goes as planned then EPP is available. */ 910 911 static u8 cmd[6] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 912 int loop, old_mode, status, k, ppb = dev->base; 913 unsigned char l; 914 915 old_mode = dev->mode; 916 for (loop = 0; loop < 8; loop++) { 917 /* Attempt to use EPP for Test Unit Ready */ 918 if (autodetect && (ppb & 0x0007) == 0x0000) 919 dev->mode = PPA_EPP_8; 920 921 second_pass: 922 ppa_connect(dev, CONNECT_EPP_MAYBE); 923 /* Select SCSI device */ 924 if (!ppa_select(dev, loop)) { 925 ppa_disconnect(dev); 926 continue; 927 } 928 printk(KERN_INFO "ppa: Found device at ID %i, Attempting to use %s\n", 929 loop, PPA_MODE_STRING[dev->mode]); 930 931 /* Send SCSI command */ 932 status = 1; 933 w_ctr(ppb, 0x0c); 934 for (l = 0; (l < 6) && (status); l++) 935 status = ppa_out(dev, cmd, 1); 936 937 if (!status) { 938 ppa_disconnect(dev); 939 ppa_connect(dev, CONNECT_EPP_MAYBE); 940 w_dtr(ppb, 0x40); 941 w_ctr(ppb, 0x08); 942 udelay(30); 943 w_ctr(ppb, 0x0c); 944 udelay(1000); 945 ppa_disconnect(dev); 946 udelay(1000); 947 if (dev->mode != old_mode) { 948 dev->mode = old_mode; 949 goto second_pass; 950 } 951 return -EIO; 952 } 953 w_ctr(ppb, 0x0c); 954 k = 1000000; /* 1 Second */ 955 do { 956 l = r_str(ppb); 957 k--; 958 udelay(1); 959 } while (!(l & 0x80) && (k)); 960 961 l &= 0xf0; 962 963 if (l != 0xf0) { 964 ppa_disconnect(dev); 965 ppa_connect(dev, CONNECT_EPP_MAYBE); 966 ppa_reset_pulse(ppb); 967 udelay(1000); 968 ppa_disconnect(dev); 969 udelay(1000); 970 if (dev->mode != old_mode) { 971 dev->mode = old_mode; 972 goto second_pass; 973 } 974 return -EIO; 975 } 976 ppa_disconnect(dev); 977 printk(KERN_INFO "ppa: Communication established with ID %i using %s\n", 978 loop, PPA_MODE_STRING[dev->mode]); 979 ppa_connect(dev, CONNECT_EPP_MAYBE); 980 ppa_reset_pulse(ppb); 981 udelay(1000); 982 ppa_disconnect(dev); 983 udelay(1000); 984 return 0; 985 } 986 return -ENODEV; 987 } 988 989 static const struct scsi_host_template ppa_template = { 990 .module = THIS_MODULE, 991 .proc_name = "ppa", 992 .show_info = ppa_show_info, 993 .write_info = ppa_write_info, 994 .name = "Iomega VPI0 (ppa) interface", 995 .queuecommand = ppa_queuecommand, 996 .eh_abort_handler = ppa_abort, 997 .eh_host_reset_handler = ppa_reset, 998 .bios_param = ppa_biosparam, 999 .this_id = -1, 1000 .sg_tablesize = SG_ALL, 1001 .can_queue = 1, 1002 .cmd_size = sizeof(struct scsi_pointer), 1003 }; 1004 1005 /*************************************************************************** 1006 * Parallel port probing routines * 1007 ***************************************************************************/ 1008 1009 static LIST_HEAD(ppa_hosts); 1010 1011 /* 1012 * Finds the first available device number that can be alloted to the 1013 * new ppa device and returns the address of the previous node so that 1014 * we can add to the tail and have a list in the ascending order. 1015 */ 1016 1017 static inline ppa_struct *find_parent(void) 1018 { 1019 ppa_struct *dev, *par = NULL; 1020 unsigned int cnt = 0; 1021 1022 if (list_empty(&ppa_hosts)) 1023 return NULL; 1024 1025 list_for_each_entry(dev, &ppa_hosts, list) { 1026 if (dev->dev_no != cnt) 1027 return par; 1028 cnt++; 1029 par = dev; 1030 } 1031 1032 return par; 1033 } 1034 1035 static int __ppa_attach(struct parport *pb) 1036 { 1037 struct Scsi_Host *host; 1038 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(waiting); 1039 DEFINE_WAIT(wait); 1040 ppa_struct *dev, *temp; 1041 int ports; 1042 int err = -ENOMEM; 1043 struct pardev_cb ppa_cb; 1044 1045 dev = kzalloc(sizeof(ppa_struct), GFP_KERNEL); 1046 if (!dev) 1047 return -ENOMEM; 1048 dev->base = -1; 1049 dev->mode = mode < PPA_UNKNOWN ? mode : PPA_AUTODETECT; 1050 dev->recon_tmo = PPA_RECON_TMO; 1051 init_waitqueue_head(&waiting); 1052 temp = find_parent(); 1053 if (temp) 1054 dev->dev_no = temp->dev_no + 1; 1055 1056 memset(&ppa_cb, 0, sizeof(ppa_cb)); 1057 ppa_cb.private = dev; 1058 ppa_cb.wakeup = ppa_wakeup; 1059 1060 dev->dev = parport_register_dev_model(pb, "ppa", &ppa_cb, dev->dev_no); 1061 1062 if (!dev->dev) 1063 goto out; 1064 1065 /* Claim the bus so it remembers what we do to the control 1066 * registers. [ CTR and ECP ] 1067 */ 1068 err = -EBUSY; 1069 dev->waiting = &waiting; 1070 prepare_to_wait(&waiting, &wait, TASK_UNINTERRUPTIBLE); 1071 if (ppa_pb_claim(dev)) 1072 schedule_timeout(3 * HZ); 1073 if (dev->wanted) { 1074 printk(KERN_ERR "ppa%d: failed to claim parport because " 1075 "a pardevice is owning the port for too long " 1076 "time!\n", pb->number); 1077 ppa_pb_dismiss(dev); 1078 dev->waiting = NULL; 1079 finish_wait(&waiting, &wait); 1080 goto out1; 1081 } 1082 dev->waiting = NULL; 1083 finish_wait(&waiting, &wait); 1084 dev->base = dev->dev->port->base; 1085 w_ctr(dev->base, 0x0c); 1086 1087 /* Done configuration */ 1088 1089 err = ppa_init(dev); 1090 ppa_pb_release(dev); 1091 1092 if (err) 1093 goto out1; 1094 1095 /* now the glue ... */ 1096 if (dev->mode == PPA_NIBBLE || dev->mode == PPA_PS2) 1097 ports = 3; 1098 else 1099 ports = 8; 1100 1101 INIT_DELAYED_WORK(&dev->ppa_tq, ppa_interrupt); 1102 1103 err = -ENOMEM; 1104 host = scsi_host_alloc(&ppa_template, sizeof(ppa_struct *)); 1105 if (!host) 1106 goto out1; 1107 host->no_highmem = true; 1108 host->io_port = pb->base; 1109 host->n_io_port = ports; 1110 host->dma_channel = -1; 1111 host->unique_id = pb->number; 1112 *(ppa_struct **)&host->hostdata = dev; 1113 dev->host = host; 1114 list_add_tail(&dev->list, &ppa_hosts); 1115 err = scsi_add_host(host, NULL); 1116 if (err) 1117 goto out2; 1118 scsi_scan_host(host); 1119 return 0; 1120 out2: 1121 list_del_init(&dev->list); 1122 scsi_host_put(host); 1123 out1: 1124 parport_unregister_device(dev->dev); 1125 out: 1126 kfree(dev); 1127 return err; 1128 } 1129 1130 static void ppa_attach(struct parport *pb) 1131 { 1132 __ppa_attach(pb); 1133 } 1134 1135 static void ppa_detach(struct parport *pb) 1136 { 1137 ppa_struct *dev; 1138 list_for_each_entry(dev, &ppa_hosts, list) { 1139 if (dev->dev->port == pb) { 1140 list_del_init(&dev->list); 1141 scsi_remove_host(dev->host); 1142 scsi_host_put(dev->host); 1143 parport_unregister_device(dev->dev); 1144 kfree(dev); 1145 break; 1146 } 1147 } 1148 } 1149 1150 static struct parport_driver ppa_driver = { 1151 .name = "ppa", 1152 .match_port = ppa_attach, 1153 .detach = ppa_detach, 1154 .devmodel = true, 1155 }; 1156 module_parport_driver(ppa_driver); 1157 1158 MODULE_LICENSE("GPL"); 1159