1 // SPDX-License-Identifier: GPL-2.0-only 2 /* imm.c -- low level driver for the IOMEGA MatchMaker 3 * parallel port SCSI host adapter. 4 * 5 * (The IMM is the embedded controller in the ZIP Plus drive.) 6 * 7 * My unofficial company acronym list is 21 pages long: 8 * FLA: Four letter acronym with built in facility for 9 * future expansion to five letters. 10 */ 11 12 #include <linux/init.h> 13 #include <linux/kernel.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/slab.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 /* The following #define is to avoid a clash with hosts.c */ 28 #define IMM_PROBE_SPP 0x0001 29 #define IMM_PROBE_PS2 0x0002 30 #define IMM_PROBE_ECR 0x0010 31 #define IMM_PROBE_EPP17 0x0100 32 #define IMM_PROBE_EPP19 0x0200 33 34 35 typedef struct { 36 struct pardevice *dev; /* Parport device entry */ 37 int base; /* Actual port address */ 38 int base_hi; /* Hi Base address for ECP-ISA chipset */ 39 int mode; /* Transfer mode */ 40 struct scsi_cmnd *cur_cmd; /* Current queued command */ 41 struct delayed_work imm_tq; /* Polling interrupt stuff */ 42 unsigned long jstart; /* Jiffies at start */ 43 unsigned failed:1; /* Failure flag */ 44 unsigned dp:1; /* Data phase present */ 45 unsigned rd:1; /* Read data in data phase */ 46 unsigned wanted:1; /* Parport sharing busy flag */ 47 unsigned int dev_no; /* Device number */ 48 wait_queue_head_t *waiting; 49 struct Scsi_Host *host; 50 struct list_head list; 51 } imm_struct; 52 53 static void imm_reset_pulse(unsigned int base); 54 static int device_check(imm_struct *dev); 55 56 #include "imm.h" 57 58 static inline imm_struct *imm_dev(struct Scsi_Host *host) 59 { 60 return *(imm_struct **)&host->hostdata; 61 } 62 63 static DEFINE_SPINLOCK(arbitration_lock); 64 65 static void got_it(imm_struct *dev) 66 { 67 dev->base = dev->dev->port->base; 68 if (dev->cur_cmd) 69 dev->cur_cmd->SCp.phase = 1; 70 else 71 wake_up(dev->waiting); 72 } 73 74 static void imm_wakeup(void *ref) 75 { 76 imm_struct *dev = (imm_struct *) ref; 77 unsigned long flags; 78 79 spin_lock_irqsave(&arbitration_lock, flags); 80 if (dev->wanted) { 81 if (parport_claim(dev->dev) == 0) { 82 got_it(dev); 83 dev->wanted = 0; 84 } 85 } 86 spin_unlock_irqrestore(&arbitration_lock, flags); 87 } 88 89 static int imm_pb_claim(imm_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 imm_pb_dismiss(imm_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 imm_pb_release(imm_struct *dev) 116 { 117 parport_release(dev->dev); 118 } 119 120 /* This is to give the imm driver a way to modify the timings (and other 121 * parameters) by writing to the /proc/scsi/imm/0 file. 122 * Very simple method really... (Too simple, no error checking :( ) 123 * Reason: Kernel hackers HATE having to unload and reload modules for 124 * testing... 125 * Also gives a method to use a script to obtain optimum timings (TODO) 126 */ 127 static int imm_write_info(struct Scsi_Host *host, char *buffer, int length) 128 { 129 imm_struct *dev = imm_dev(host); 130 131 if ((length > 5) && (strncmp(buffer, "mode=", 5) == 0)) { 132 dev->mode = simple_strtoul(buffer + 5, NULL, 0); 133 return length; 134 } 135 printk("imm /proc: invalid variable\n"); 136 return -EINVAL; 137 } 138 139 static int imm_show_info(struct seq_file *m, struct Scsi_Host *host) 140 { 141 imm_struct *dev = imm_dev(host); 142 143 seq_printf(m, "Version : %s\n", IMM_VERSION); 144 seq_printf(m, "Parport : %s\n", dev->dev->port->name); 145 seq_printf(m, "Mode : %s\n", IMM_MODE_STRING[dev->mode]); 146 return 0; 147 } 148 149 #if IMM_DEBUG > 0 150 #define imm_fail(x,y) printk("imm: imm_fail(%i) from %s at line %d\n",\ 151 y, __func__, __LINE__); imm_fail_func(x,y); 152 static inline void 153 imm_fail_func(imm_struct *dev, int error_code) 154 #else 155 static inline void 156 imm_fail(imm_struct *dev, int error_code) 157 #endif 158 { 159 /* If we fail a device then we trash status / message bytes */ 160 if (dev->cur_cmd) { 161 dev->cur_cmd->result = error_code << 16; 162 dev->failed = 1; 163 } 164 } 165 166 /* 167 * Wait for the high bit to be set. 168 * 169 * In principle, this could be tied to an interrupt, but the adapter 170 * doesn't appear to be designed to support interrupts. We spin on 171 * the 0x80 ready bit. 172 */ 173 static unsigned char imm_wait(imm_struct *dev) 174 { 175 int k; 176 unsigned short ppb = dev->base; 177 unsigned char r; 178 179 w_ctr(ppb, 0x0c); 180 181 k = IMM_SPIN_TMO; 182 do { 183 r = r_str(ppb); 184 k--; 185 udelay(1); 186 } 187 while (!(r & 0x80) && (k)); 188 189 /* 190 * STR register (LPT base+1) to SCSI mapping: 191 * 192 * STR imm imm 193 * =================================== 194 * 0x80 S_REQ S_REQ 195 * 0x40 !S_BSY (????) 196 * 0x20 !S_CD !S_CD 197 * 0x10 !S_IO !S_IO 198 * 0x08 (????) !S_BSY 199 * 200 * imm imm meaning 201 * ================================== 202 * 0xf0 0xb8 Bit mask 203 * 0xc0 0x88 ZIP wants more data 204 * 0xd0 0x98 ZIP wants to send more data 205 * 0xe0 0xa8 ZIP is expecting SCSI command data 206 * 0xf0 0xb8 end of transfer, ZIP is sending status 207 */ 208 w_ctr(ppb, 0x04); 209 if (k) 210 return (r & 0xb8); 211 212 /* Counter expired - Time out occurred */ 213 imm_fail(dev, DID_TIME_OUT); 214 printk("imm timeout in imm_wait\n"); 215 return 0; /* command timed out */ 216 } 217 218 static int imm_negotiate(imm_struct * tmp) 219 { 220 /* 221 * The following is supposedly the IEEE 1284-1994 negotiate 222 * sequence. I have yet to obtain a copy of the above standard 223 * so this is a bit of a guess... 224 * 225 * A fair chunk of this is based on the Linux parport implementation 226 * of IEEE 1284. 227 * 228 * Return 0 if data available 229 * 1 if no data available 230 */ 231 232 unsigned short base = tmp->base; 233 unsigned char a, mode; 234 235 switch (tmp->mode) { 236 case IMM_NIBBLE: 237 mode = 0x00; 238 break; 239 case IMM_PS2: 240 mode = 0x01; 241 break; 242 default: 243 return 0; 244 } 245 246 w_ctr(base, 0x04); 247 udelay(5); 248 w_dtr(base, mode); 249 udelay(100); 250 w_ctr(base, 0x06); 251 udelay(5); 252 a = (r_str(base) & 0x20) ? 0 : 1; 253 udelay(5); 254 w_ctr(base, 0x07); 255 udelay(5); 256 w_ctr(base, 0x06); 257 258 if (a) { 259 printk 260 ("IMM: IEEE1284 negotiate indicates no data available.\n"); 261 imm_fail(tmp, DID_ERROR); 262 } 263 return a; 264 } 265 266 /* 267 * Clear EPP timeout bit. 268 */ 269 static inline void epp_reset(unsigned short ppb) 270 { 271 int i; 272 273 i = r_str(ppb); 274 w_str(ppb, i); 275 w_str(ppb, i & 0xfe); 276 } 277 278 /* 279 * Wait for empty ECP fifo (if we are in ECP fifo mode only) 280 */ 281 static inline void ecp_sync(imm_struct *dev) 282 { 283 int i, ppb_hi = dev->base_hi; 284 285 if (ppb_hi == 0) 286 return; 287 288 if ((r_ecr(ppb_hi) & 0xe0) == 0x60) { /* mode 011 == ECP fifo mode */ 289 for (i = 0; i < 100; i++) { 290 if (r_ecr(ppb_hi) & 0x01) 291 return; 292 udelay(5); 293 } 294 printk("imm: ECP sync failed as data still present in FIFO.\n"); 295 } 296 } 297 298 static int imm_byte_out(unsigned short base, const char *buffer, int len) 299 { 300 int i; 301 302 w_ctr(base, 0x4); /* apparently a sane mode */ 303 for (i = len >> 1; i; i--) { 304 w_dtr(base, *buffer++); 305 w_ctr(base, 0x5); /* Drop STROBE low */ 306 w_dtr(base, *buffer++); 307 w_ctr(base, 0x0); /* STROBE high + INIT low */ 308 } 309 w_ctr(base, 0x4); /* apparently a sane mode */ 310 return 1; /* All went well - we hope! */ 311 } 312 313 static int imm_nibble_in(unsigned short base, char *buffer, int len) 314 { 315 unsigned char l; 316 int i; 317 318 /* 319 * The following is based on documented timing signals 320 */ 321 w_ctr(base, 0x4); 322 for (i = len; i; i--) { 323 w_ctr(base, 0x6); 324 l = (r_str(base) & 0xf0) >> 4; 325 w_ctr(base, 0x5); 326 *buffer++ = (r_str(base) & 0xf0) | l; 327 w_ctr(base, 0x4); 328 } 329 return 1; /* All went well - we hope! */ 330 } 331 332 static int imm_byte_in(unsigned short base, char *buffer, int len) 333 { 334 int i; 335 336 /* 337 * The following is based on documented timing signals 338 */ 339 w_ctr(base, 0x4); 340 for (i = len; i; i--) { 341 w_ctr(base, 0x26); 342 *buffer++ = r_dtr(base); 343 w_ctr(base, 0x25); 344 } 345 return 1; /* All went well - we hope! */ 346 } 347 348 static int imm_out(imm_struct *dev, char *buffer, int len) 349 { 350 unsigned short ppb = dev->base; 351 int r = imm_wait(dev); 352 353 /* 354 * Make sure that: 355 * a) the SCSI bus is BUSY (device still listening) 356 * b) the device is listening 357 */ 358 if ((r & 0x18) != 0x08) { 359 imm_fail(dev, DID_ERROR); 360 printk("IMM: returned SCSI status %2x\n", r); 361 return 0; 362 } 363 switch (dev->mode) { 364 case IMM_EPP_32: 365 case IMM_EPP_16: 366 case IMM_EPP_8: 367 epp_reset(ppb); 368 w_ctr(ppb, 0x4); 369 #ifdef CONFIG_SCSI_IZIP_EPP16 370 if (!(((long) buffer | len) & 0x01)) 371 outsw(ppb + 4, buffer, len >> 1); 372 #else 373 if (!(((long) buffer | len) & 0x03)) 374 outsl(ppb + 4, buffer, len >> 2); 375 #endif 376 else 377 outsb(ppb + 4, buffer, len); 378 w_ctr(ppb, 0xc); 379 r = !(r_str(ppb) & 0x01); 380 w_ctr(ppb, 0xc); 381 ecp_sync(dev); 382 break; 383 384 case IMM_NIBBLE: 385 case IMM_PS2: 386 /* 8 bit output, with a loop */ 387 r = imm_byte_out(ppb, buffer, len); 388 break; 389 390 default: 391 printk("IMM: bug in imm_out()\n"); 392 r = 0; 393 } 394 return r; 395 } 396 397 static int imm_in(imm_struct *dev, char *buffer, int len) 398 { 399 unsigned short ppb = dev->base; 400 int r = imm_wait(dev); 401 402 /* 403 * Make sure that: 404 * a) the SCSI bus is BUSY (device still listening) 405 * b) the device is sending data 406 */ 407 if ((r & 0x18) != 0x18) { 408 imm_fail(dev, DID_ERROR); 409 return 0; 410 } 411 switch (dev->mode) { 412 case IMM_NIBBLE: 413 /* 4 bit input, with a loop */ 414 r = imm_nibble_in(ppb, buffer, len); 415 w_ctr(ppb, 0xc); 416 break; 417 418 case IMM_PS2: 419 /* 8 bit input, with a loop */ 420 r = imm_byte_in(ppb, buffer, len); 421 w_ctr(ppb, 0xc); 422 break; 423 424 case IMM_EPP_32: 425 case IMM_EPP_16: 426 case IMM_EPP_8: 427 epp_reset(ppb); 428 w_ctr(ppb, 0x24); 429 #ifdef CONFIG_SCSI_IZIP_EPP16 430 if (!(((long) buffer | len) & 0x01)) 431 insw(ppb + 4, buffer, len >> 1); 432 #else 433 if (!(((long) buffer | len) & 0x03)) 434 insl(ppb + 4, buffer, len >> 2); 435 #endif 436 else 437 insb(ppb + 4, buffer, len); 438 w_ctr(ppb, 0x2c); 439 r = !(r_str(ppb) & 0x01); 440 w_ctr(ppb, 0x2c); 441 ecp_sync(dev); 442 break; 443 444 default: 445 printk("IMM: bug in imm_ins()\n"); 446 r = 0; 447 break; 448 } 449 return r; 450 } 451 452 static int imm_cpp(unsigned short ppb, unsigned char b) 453 { 454 /* 455 * Comments on udelay values refer to the 456 * Command Packet Protocol (CPP) timing diagram. 457 */ 458 459 unsigned char s1, s2, s3; 460 w_ctr(ppb, 0x0c); 461 udelay(2); /* 1 usec - infinite */ 462 w_dtr(ppb, 0xaa); 463 udelay(10); /* 7 usec - infinite */ 464 w_dtr(ppb, 0x55); 465 udelay(10); /* 7 usec - infinite */ 466 w_dtr(ppb, 0x00); 467 udelay(10); /* 7 usec - infinite */ 468 w_dtr(ppb, 0xff); 469 udelay(10); /* 7 usec - infinite */ 470 s1 = r_str(ppb) & 0xb8; 471 w_dtr(ppb, 0x87); 472 udelay(10); /* 7 usec - infinite */ 473 s2 = r_str(ppb) & 0xb8; 474 w_dtr(ppb, 0x78); 475 udelay(10); /* 7 usec - infinite */ 476 s3 = r_str(ppb) & 0x38; 477 /* 478 * Values for b are: 479 * 0000 00aa Assign address aa to current device 480 * 0010 00aa Select device aa in EPP Winbond mode 481 * 0010 10aa Select device aa in EPP mode 482 * 0011 xxxx Deselect all devices 483 * 0110 00aa Test device aa 484 * 1101 00aa Select device aa in ECP mode 485 * 1110 00aa Select device aa in Compatible mode 486 */ 487 w_dtr(ppb, b); 488 udelay(2); /* 1 usec - infinite */ 489 w_ctr(ppb, 0x0c); 490 udelay(10); /* 7 usec - infinite */ 491 w_ctr(ppb, 0x0d); 492 udelay(2); /* 1 usec - infinite */ 493 w_ctr(ppb, 0x0c); 494 udelay(10); /* 7 usec - infinite */ 495 w_dtr(ppb, 0xff); 496 udelay(10); /* 7 usec - infinite */ 497 498 /* 499 * The following table is electrical pin values. 500 * (BSY is inverted at the CTR register) 501 * 502 * BSY ACK POut SEL Fault 503 * S1 0 X 1 1 1 504 * S2 1 X 0 1 1 505 * S3 L X 1 1 S 506 * 507 * L => Last device in chain 508 * S => Selected 509 * 510 * Observered values for S1,S2,S3 are: 511 * Disconnect => f8/58/78 512 * Connect => f8/58/70 513 */ 514 if ((s1 == 0xb8) && (s2 == 0x18) && (s3 == 0x30)) 515 return 1; /* Connected */ 516 if ((s1 == 0xb8) && (s2 == 0x18) && (s3 == 0x38)) 517 return 0; /* Disconnected */ 518 519 return -1; /* No device present */ 520 } 521 522 static inline int imm_connect(imm_struct *dev, int flag) 523 { 524 unsigned short ppb = dev->base; 525 526 imm_cpp(ppb, 0xe0); /* Select device 0 in compatible mode */ 527 imm_cpp(ppb, 0x30); /* Disconnect all devices */ 528 529 if ((dev->mode == IMM_EPP_8) || 530 (dev->mode == IMM_EPP_16) || 531 (dev->mode == IMM_EPP_32)) 532 return imm_cpp(ppb, 0x28); /* Select device 0 in EPP mode */ 533 return imm_cpp(ppb, 0xe0); /* Select device 0 in compatible mode */ 534 } 535 536 static void imm_disconnect(imm_struct *dev) 537 { 538 imm_cpp(dev->base, 0x30); /* Disconnect all devices */ 539 } 540 541 static int imm_select(imm_struct *dev, int target) 542 { 543 int k; 544 unsigned short ppb = dev->base; 545 546 /* 547 * Firstly we want to make sure there is nothing 548 * holding onto the SCSI bus. 549 */ 550 w_ctr(ppb, 0xc); 551 552 k = IMM_SELECT_TMO; 553 do { 554 k--; 555 } while ((r_str(ppb) & 0x08) && (k)); 556 557 if (!k) 558 return 0; 559 560 /* 561 * Now assert the SCSI ID (HOST and TARGET) on the data bus 562 */ 563 w_ctr(ppb, 0x4); 564 w_dtr(ppb, 0x80 | (1 << target)); 565 udelay(1); 566 567 /* 568 * Deassert SELIN first followed by STROBE 569 */ 570 w_ctr(ppb, 0xc); 571 w_ctr(ppb, 0xd); 572 573 /* 574 * ACK should drop low while SELIN is deasserted. 575 * FAULT should drop low when the SCSI device latches the bus. 576 */ 577 k = IMM_SELECT_TMO; 578 do { 579 k--; 580 } 581 while (!(r_str(ppb) & 0x08) && (k)); 582 583 /* 584 * Place the interface back into a sane state (status mode) 585 */ 586 w_ctr(ppb, 0xc); 587 return (k) ? 1 : 0; 588 } 589 590 static int imm_init(imm_struct *dev) 591 { 592 if (imm_connect(dev, 0) != 1) 593 return -EIO; 594 imm_reset_pulse(dev->base); 595 mdelay(1); /* Delay to allow devices to settle */ 596 imm_disconnect(dev); 597 mdelay(1); /* Another delay to allow devices to settle */ 598 return device_check(dev); 599 } 600 601 static inline int imm_send_command(struct scsi_cmnd *cmd) 602 { 603 imm_struct *dev = imm_dev(cmd->device->host); 604 int k; 605 606 /* NOTE: IMM uses byte pairs */ 607 for (k = 0; k < cmd->cmd_len; k += 2) 608 if (!imm_out(dev, &cmd->cmnd[k], 2)) 609 return 0; 610 return 1; 611 } 612 613 /* 614 * The bulk flag enables some optimisations in the data transfer loops, 615 * it should be true for any command that transfers data in integral 616 * numbers of sectors. 617 * 618 * The driver appears to remain stable if we speed up the parallel port 619 * i/o in this function, but not elsewhere. 620 */ 621 static int imm_completion(struct scsi_cmnd *cmd) 622 { 623 /* Return codes: 624 * -1 Error 625 * 0 Told to schedule 626 * 1 Finished data transfer 627 */ 628 imm_struct *dev = imm_dev(cmd->device->host); 629 unsigned short ppb = dev->base; 630 unsigned long start_jiffies = jiffies; 631 632 unsigned char r, v; 633 int fast, bulk, status; 634 635 v = cmd->cmnd[0]; 636 bulk = ((v == READ_6) || 637 (v == READ_10) || (v == WRITE_6) || (v == WRITE_10)); 638 639 /* 640 * We only get here if the drive is ready to comunicate, 641 * hence no need for a full imm_wait. 642 */ 643 w_ctr(ppb, 0x0c); 644 r = (r_str(ppb) & 0xb8); 645 646 /* 647 * while (device is not ready to send status byte) 648 * loop; 649 */ 650 while (r != (unsigned char) 0xb8) { 651 /* 652 * If we have been running for more than a full timer tick 653 * then take a rest. 654 */ 655 if (time_after(jiffies, start_jiffies + 1)) 656 return 0; 657 658 /* 659 * FAIL if: 660 * a) Drive status is screwy (!ready && !present) 661 * b) Drive is requesting/sending more data than expected 662 */ 663 if (((r & 0x88) != 0x88) || (cmd->SCp.this_residual <= 0)) { 664 imm_fail(dev, DID_ERROR); 665 return -1; /* ERROR_RETURN */ 666 } 667 /* determine if we should use burst I/O */ 668 if (dev->rd == 0) { 669 fast = (bulk 670 && (cmd->SCp.this_residual >= 671 IMM_BURST_SIZE)) ? IMM_BURST_SIZE : 2; 672 status = imm_out(dev, cmd->SCp.ptr, fast); 673 } else { 674 fast = (bulk 675 && (cmd->SCp.this_residual >= 676 IMM_BURST_SIZE)) ? IMM_BURST_SIZE : 1; 677 status = imm_in(dev, cmd->SCp.ptr, fast); 678 } 679 680 cmd->SCp.ptr += fast; 681 cmd->SCp.this_residual -= fast; 682 683 if (!status) { 684 imm_fail(dev, DID_BUS_BUSY); 685 return -1; /* ERROR_RETURN */ 686 } 687 if (cmd->SCp.buffer && !cmd->SCp.this_residual) { 688 /* if scatter/gather, advance to the next segment */ 689 if (cmd->SCp.buffers_residual--) { 690 cmd->SCp.buffer = sg_next(cmd->SCp.buffer); 691 cmd->SCp.this_residual = 692 cmd->SCp.buffer->length; 693 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); 694 695 /* 696 * Make sure that we transfer even number of bytes 697 * otherwise it makes imm_byte_out() messy. 698 */ 699 if (cmd->SCp.this_residual & 0x01) 700 cmd->SCp.this_residual++; 701 } 702 } 703 /* Now check to see if the drive is ready to comunicate */ 704 w_ctr(ppb, 0x0c); 705 r = (r_str(ppb) & 0xb8); 706 707 /* If not, drop back down to the scheduler and wait a timer tick */ 708 if (!(r & 0x80)) 709 return 0; 710 } 711 return 1; /* FINISH_RETURN */ 712 } 713 714 /* 715 * Since the IMM itself doesn't generate interrupts, we use 716 * the scheduler's task queue to generate a stream of call-backs and 717 * complete the request when the drive is ready. 718 */ 719 static void imm_interrupt(struct work_struct *work) 720 { 721 imm_struct *dev = container_of(work, imm_struct, imm_tq.work); 722 struct scsi_cmnd *cmd = dev->cur_cmd; 723 struct Scsi_Host *host = cmd->device->host; 724 unsigned long flags; 725 726 if (imm_engine(dev, cmd)) { 727 schedule_delayed_work(&dev->imm_tq, 1); 728 return; 729 } 730 /* Command must of completed hence it is safe to let go... */ 731 #if IMM_DEBUG > 0 732 switch ((cmd->result >> 16) & 0xff) { 733 case DID_OK: 734 break; 735 case DID_NO_CONNECT: 736 printk("imm: no device at SCSI ID %i\n", cmd->device->id); 737 break; 738 case DID_BUS_BUSY: 739 printk("imm: BUS BUSY - EPP timeout detected\n"); 740 break; 741 case DID_TIME_OUT: 742 printk("imm: unknown timeout\n"); 743 break; 744 case DID_ABORT: 745 printk("imm: told to abort\n"); 746 break; 747 case DID_PARITY: 748 printk("imm: parity error (???)\n"); 749 break; 750 case DID_ERROR: 751 printk("imm: internal driver error\n"); 752 break; 753 case DID_RESET: 754 printk("imm: told to reset device\n"); 755 break; 756 case DID_BAD_INTR: 757 printk("imm: bad interrupt (???)\n"); 758 break; 759 default: 760 printk("imm: bad return code (%02x)\n", 761 (cmd->result >> 16) & 0xff); 762 } 763 #endif 764 765 if (cmd->SCp.phase > 1) 766 imm_disconnect(dev); 767 768 imm_pb_dismiss(dev); 769 770 spin_lock_irqsave(host->host_lock, flags); 771 dev->cur_cmd = NULL; 772 cmd->scsi_done(cmd); 773 spin_unlock_irqrestore(host->host_lock, flags); 774 return; 775 } 776 777 static int imm_engine(imm_struct *dev, struct scsi_cmnd *cmd) 778 { 779 unsigned short ppb = dev->base; 780 unsigned char l = 0, h = 0; 781 int retv, x; 782 783 /* First check for any errors that may have occurred 784 * Here we check for internal errors 785 */ 786 if (dev->failed) 787 return 0; 788 789 switch (cmd->SCp.phase) { 790 case 0: /* Phase 0 - Waiting for parport */ 791 if (time_after(jiffies, dev->jstart + HZ)) { 792 /* 793 * We waited more than a second 794 * for parport to call us 795 */ 796 imm_fail(dev, DID_BUS_BUSY); 797 return 0; 798 } 799 return 1; /* wait until imm_wakeup claims parport */ 800 801 case 1: /* Phase 1 - Connected */ 802 imm_connect(dev, CONNECT_EPP_MAYBE); 803 cmd->SCp.phase++; 804 fallthrough; 805 806 case 2: /* Phase 2 - We are now talking to the scsi bus */ 807 if (!imm_select(dev, scmd_id(cmd))) { 808 imm_fail(dev, DID_NO_CONNECT); 809 return 0; 810 } 811 cmd->SCp.phase++; 812 fallthrough; 813 814 case 3: /* Phase 3 - Ready to accept a command */ 815 w_ctr(ppb, 0x0c); 816 if (!(r_str(ppb) & 0x80)) 817 return 1; 818 819 if (!imm_send_command(cmd)) 820 return 0; 821 cmd->SCp.phase++; 822 fallthrough; 823 824 case 4: /* Phase 4 - Setup scatter/gather buffers */ 825 if (scsi_bufflen(cmd)) { 826 cmd->SCp.buffer = scsi_sglist(cmd); 827 cmd->SCp.this_residual = cmd->SCp.buffer->length; 828 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); 829 } else { 830 cmd->SCp.buffer = NULL; 831 cmd->SCp.this_residual = 0; 832 cmd->SCp.ptr = NULL; 833 } 834 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1; 835 cmd->SCp.phase++; 836 if (cmd->SCp.this_residual & 0x01) 837 cmd->SCp.this_residual++; 838 fallthrough; 839 840 case 5: /* Phase 5 - Pre-Data transfer stage */ 841 /* Spin lock for BUSY */ 842 w_ctr(ppb, 0x0c); 843 if (!(r_str(ppb) & 0x80)) 844 return 1; 845 846 /* Require negotiation for read requests */ 847 x = (r_str(ppb) & 0xb8); 848 dev->rd = (x & 0x10) ? 1 : 0; 849 dev->dp = (x & 0x20) ? 0 : 1; 850 851 if ((dev->dp) && (dev->rd)) 852 if (imm_negotiate(dev)) 853 return 0; 854 cmd->SCp.phase++; 855 fallthrough; 856 857 case 6: /* Phase 6 - Data transfer stage */ 858 /* Spin lock for BUSY */ 859 w_ctr(ppb, 0x0c); 860 if (!(r_str(ppb) & 0x80)) 861 return 1; 862 863 if (dev->dp) { 864 retv = imm_completion(cmd); 865 if (retv == -1) 866 return 0; 867 if (retv == 0) 868 return 1; 869 } 870 cmd->SCp.phase++; 871 fallthrough; 872 873 case 7: /* Phase 7 - Post data transfer stage */ 874 if ((dev->dp) && (dev->rd)) { 875 if ((dev->mode == IMM_NIBBLE) || (dev->mode == IMM_PS2)) { 876 w_ctr(ppb, 0x4); 877 w_ctr(ppb, 0xc); 878 w_ctr(ppb, 0xe); 879 w_ctr(ppb, 0x4); 880 } 881 } 882 cmd->SCp.phase++; 883 fallthrough; 884 885 case 8: /* Phase 8 - Read status/message */ 886 /* Check for data overrun */ 887 if (imm_wait(dev) != (unsigned char) 0xb8) { 888 imm_fail(dev, DID_ERROR); 889 return 0; 890 } 891 if (imm_negotiate(dev)) 892 return 0; 893 if (imm_in(dev, &l, 1)) { /* read status byte */ 894 /* Check for optional message byte */ 895 if (imm_wait(dev) == (unsigned char) 0xb8) 896 imm_in(dev, &h, 1); 897 cmd->result = (DID_OK << 16) | (l & STATUS_MASK); 898 } 899 if ((dev->mode == IMM_NIBBLE) || (dev->mode == IMM_PS2)) { 900 w_ctr(ppb, 0x4); 901 w_ctr(ppb, 0xc); 902 w_ctr(ppb, 0xe); 903 w_ctr(ppb, 0x4); 904 } 905 return 0; /* Finished */ 906 907 default: 908 printk("imm: Invalid scsi phase\n"); 909 } 910 return 0; 911 } 912 913 static int imm_queuecommand_lck(struct scsi_cmnd *cmd, 914 void (*done)(struct scsi_cmnd *)) 915 { 916 imm_struct *dev = imm_dev(cmd->device->host); 917 918 if (dev->cur_cmd) { 919 printk("IMM: bug in imm_queuecommand\n"); 920 return 0; 921 } 922 dev->failed = 0; 923 dev->jstart = jiffies; 924 dev->cur_cmd = cmd; 925 cmd->scsi_done = done; 926 cmd->result = DID_ERROR << 16; /* default return code */ 927 cmd->SCp.phase = 0; /* bus free */ 928 929 schedule_delayed_work(&dev->imm_tq, 0); 930 931 imm_pb_claim(dev); 932 933 return 0; 934 } 935 936 static DEF_SCSI_QCMD(imm_queuecommand) 937 938 /* 939 * Apparently the disk->capacity attribute is off by 1 sector 940 * for all disk drives. We add the one here, but it should really 941 * be done in sd.c. Even if it gets fixed there, this will still 942 * work. 943 */ 944 static int imm_biosparam(struct scsi_device *sdev, struct block_device *dev, 945 sector_t capacity, int ip[]) 946 { 947 ip[0] = 0x40; 948 ip[1] = 0x20; 949 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]); 950 if (ip[2] > 1024) { 951 ip[0] = 0xff; 952 ip[1] = 0x3f; 953 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]); 954 } 955 return 0; 956 } 957 958 static int imm_abort(struct scsi_cmnd *cmd) 959 { 960 imm_struct *dev = imm_dev(cmd->device->host); 961 /* 962 * There is no method for aborting commands since Iomega 963 * have tied the SCSI_MESSAGE line high in the interface 964 */ 965 966 switch (cmd->SCp.phase) { 967 case 0: /* Do not have access to parport */ 968 case 1: /* Have not connected to interface */ 969 dev->cur_cmd = NULL; /* Forget the problem */ 970 return SUCCESS; 971 default: /* SCSI command sent, can not abort */ 972 return FAILED; 973 } 974 } 975 976 static void imm_reset_pulse(unsigned int base) 977 { 978 w_ctr(base, 0x04); 979 w_dtr(base, 0x40); 980 udelay(1); 981 w_ctr(base, 0x0c); 982 w_ctr(base, 0x0d); 983 udelay(50); 984 w_ctr(base, 0x0c); 985 w_ctr(base, 0x04); 986 } 987 988 static int imm_reset(struct scsi_cmnd *cmd) 989 { 990 imm_struct *dev = imm_dev(cmd->device->host); 991 992 if (cmd->SCp.phase) 993 imm_disconnect(dev); 994 dev->cur_cmd = NULL; /* Forget the problem */ 995 996 imm_connect(dev, CONNECT_NORMAL); 997 imm_reset_pulse(dev->base); 998 mdelay(1); /* device settle delay */ 999 imm_disconnect(dev); 1000 mdelay(1); /* device settle delay */ 1001 return SUCCESS; 1002 } 1003 1004 static int device_check(imm_struct *dev) 1005 { 1006 /* This routine looks for a device and then attempts to use EPP 1007 to send a command. If all goes as planned then EPP is available. */ 1008 1009 static char cmd[6] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 1010 int loop, old_mode, status, k, ppb = dev->base; 1011 unsigned char l; 1012 1013 old_mode = dev->mode; 1014 for (loop = 0; loop < 8; loop++) { 1015 /* Attempt to use EPP for Test Unit Ready */ 1016 if ((ppb & 0x0007) == 0x0000) 1017 dev->mode = IMM_EPP_32; 1018 1019 second_pass: 1020 imm_connect(dev, CONNECT_EPP_MAYBE); 1021 /* Select SCSI device */ 1022 if (!imm_select(dev, loop)) { 1023 imm_disconnect(dev); 1024 continue; 1025 } 1026 printk("imm: Found device at ID %i, Attempting to use %s\n", 1027 loop, IMM_MODE_STRING[dev->mode]); 1028 1029 /* Send SCSI command */ 1030 status = 1; 1031 w_ctr(ppb, 0x0c); 1032 for (l = 0; (l < 3) && (status); l++) 1033 status = imm_out(dev, &cmd[l << 1], 2); 1034 1035 if (!status) { 1036 imm_disconnect(dev); 1037 imm_connect(dev, CONNECT_EPP_MAYBE); 1038 imm_reset_pulse(dev->base); 1039 udelay(1000); 1040 imm_disconnect(dev); 1041 udelay(1000); 1042 if (dev->mode == IMM_EPP_32) { 1043 dev->mode = old_mode; 1044 goto second_pass; 1045 } 1046 printk("imm: Unable to establish communication\n"); 1047 return -EIO; 1048 } 1049 w_ctr(ppb, 0x0c); 1050 1051 k = 1000000; /* 1 Second */ 1052 do { 1053 l = r_str(ppb); 1054 k--; 1055 udelay(1); 1056 } while (!(l & 0x80) && (k)); 1057 1058 l &= 0xb8; 1059 1060 if (l != 0xb8) { 1061 imm_disconnect(dev); 1062 imm_connect(dev, CONNECT_EPP_MAYBE); 1063 imm_reset_pulse(dev->base); 1064 udelay(1000); 1065 imm_disconnect(dev); 1066 udelay(1000); 1067 if (dev->mode == IMM_EPP_32) { 1068 dev->mode = old_mode; 1069 goto second_pass; 1070 } 1071 printk 1072 ("imm: Unable to establish communication\n"); 1073 return -EIO; 1074 } 1075 imm_disconnect(dev); 1076 printk 1077 ("imm: Communication established at 0x%x with ID %i using %s\n", 1078 ppb, loop, IMM_MODE_STRING[dev->mode]); 1079 imm_connect(dev, CONNECT_EPP_MAYBE); 1080 imm_reset_pulse(dev->base); 1081 udelay(1000); 1082 imm_disconnect(dev); 1083 udelay(1000); 1084 return 0; 1085 } 1086 printk("imm: No devices found\n"); 1087 return -ENODEV; 1088 } 1089 1090 /* 1091 * imm cannot deal with highmem, so this causes all IO pages for this host 1092 * to reside in low memory (hence mapped) 1093 */ 1094 static int imm_adjust_queue(struct scsi_device *device) 1095 { 1096 blk_queue_bounce_limit(device->request_queue, BLK_BOUNCE_HIGH); 1097 return 0; 1098 } 1099 1100 static struct scsi_host_template imm_template = { 1101 .module = THIS_MODULE, 1102 .proc_name = "imm", 1103 .show_info = imm_show_info, 1104 .write_info = imm_write_info, 1105 .name = "Iomega VPI2 (imm) interface", 1106 .queuecommand = imm_queuecommand, 1107 .eh_abort_handler = imm_abort, 1108 .eh_host_reset_handler = imm_reset, 1109 .bios_param = imm_biosparam, 1110 .this_id = 7, 1111 .sg_tablesize = SG_ALL, 1112 .can_queue = 1, 1113 .slave_alloc = imm_adjust_queue, 1114 }; 1115 1116 /*************************************************************************** 1117 * Parallel port probing routines * 1118 ***************************************************************************/ 1119 1120 static LIST_HEAD(imm_hosts); 1121 1122 /* 1123 * Finds the first available device number that can be alloted to the 1124 * new imm device and returns the address of the previous node so that 1125 * we can add to the tail and have a list in the ascending order. 1126 */ 1127 1128 static inline imm_struct *find_parent(void) 1129 { 1130 imm_struct *dev, *par = NULL; 1131 unsigned int cnt = 0; 1132 1133 if (list_empty(&imm_hosts)) 1134 return NULL; 1135 1136 list_for_each_entry(dev, &imm_hosts, list) { 1137 if (dev->dev_no != cnt) 1138 return par; 1139 cnt++; 1140 par = dev; 1141 } 1142 1143 return par; 1144 } 1145 1146 static int __imm_attach(struct parport *pb) 1147 { 1148 struct Scsi_Host *host; 1149 imm_struct *dev, *temp; 1150 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(waiting); 1151 DEFINE_WAIT(wait); 1152 int ports; 1153 int modes, ppb; 1154 int err = -ENOMEM; 1155 struct pardev_cb imm_cb; 1156 1157 init_waitqueue_head(&waiting); 1158 1159 dev = kzalloc(sizeof(imm_struct), GFP_KERNEL); 1160 if (!dev) 1161 return -ENOMEM; 1162 1163 1164 dev->base = -1; 1165 dev->mode = IMM_AUTODETECT; 1166 INIT_LIST_HEAD(&dev->list); 1167 1168 temp = find_parent(); 1169 if (temp) 1170 dev->dev_no = temp->dev_no + 1; 1171 1172 memset(&imm_cb, 0, sizeof(imm_cb)); 1173 imm_cb.private = dev; 1174 imm_cb.wakeup = imm_wakeup; 1175 1176 dev->dev = parport_register_dev_model(pb, "imm", &imm_cb, dev->dev_no); 1177 if (!dev->dev) 1178 goto out; 1179 1180 1181 /* Claim the bus so it remembers what we do to the control 1182 * registers. [ CTR and ECP ] 1183 */ 1184 err = -EBUSY; 1185 dev->waiting = &waiting; 1186 prepare_to_wait(&waiting, &wait, TASK_UNINTERRUPTIBLE); 1187 if (imm_pb_claim(dev)) 1188 schedule_timeout(3 * HZ); 1189 if (dev->wanted) { 1190 printk(KERN_ERR "imm%d: failed to claim parport because " 1191 "a pardevice is owning the port for too long " 1192 "time!\n", pb->number); 1193 imm_pb_dismiss(dev); 1194 dev->waiting = NULL; 1195 finish_wait(&waiting, &wait); 1196 goto out1; 1197 } 1198 dev->waiting = NULL; 1199 finish_wait(&waiting, &wait); 1200 ppb = dev->base = dev->dev->port->base; 1201 dev->base_hi = dev->dev->port->base_hi; 1202 w_ctr(ppb, 0x0c); 1203 modes = dev->dev->port->modes; 1204 1205 /* Mode detection works up the chain of speed 1206 * This avoids a nasty if-then-else-if-... tree 1207 */ 1208 dev->mode = IMM_NIBBLE; 1209 1210 if (modes & PARPORT_MODE_TRISTATE) 1211 dev->mode = IMM_PS2; 1212 1213 /* Done configuration */ 1214 1215 err = imm_init(dev); 1216 1217 imm_pb_release(dev); 1218 1219 if (err) 1220 goto out1; 1221 1222 /* now the glue ... */ 1223 if (dev->mode == IMM_NIBBLE || dev->mode == IMM_PS2) 1224 ports = 3; 1225 else 1226 ports = 8; 1227 1228 INIT_DELAYED_WORK(&dev->imm_tq, imm_interrupt); 1229 1230 err = -ENOMEM; 1231 host = scsi_host_alloc(&imm_template, sizeof(imm_struct *)); 1232 if (!host) 1233 goto out1; 1234 host->io_port = pb->base; 1235 host->n_io_port = ports; 1236 host->dma_channel = -1; 1237 host->unique_id = pb->number; 1238 *(imm_struct **)&host->hostdata = dev; 1239 dev->host = host; 1240 if (!temp) 1241 list_add_tail(&dev->list, &imm_hosts); 1242 else 1243 list_add_tail(&dev->list, &temp->list); 1244 err = scsi_add_host(host, NULL); 1245 if (err) 1246 goto out2; 1247 scsi_scan_host(host); 1248 return 0; 1249 1250 out2: 1251 list_del_init(&dev->list); 1252 scsi_host_put(host); 1253 out1: 1254 parport_unregister_device(dev->dev); 1255 out: 1256 kfree(dev); 1257 return err; 1258 } 1259 1260 static void imm_attach(struct parport *pb) 1261 { 1262 __imm_attach(pb); 1263 } 1264 1265 static void imm_detach(struct parport *pb) 1266 { 1267 imm_struct *dev; 1268 list_for_each_entry(dev, &imm_hosts, list) { 1269 if (dev->dev->port == pb) { 1270 list_del_init(&dev->list); 1271 scsi_remove_host(dev->host); 1272 scsi_host_put(dev->host); 1273 parport_unregister_device(dev->dev); 1274 kfree(dev); 1275 break; 1276 } 1277 } 1278 } 1279 1280 static struct parport_driver imm_driver = { 1281 .name = "imm", 1282 .match_port = imm_attach, 1283 .detach = imm_detach, 1284 .devmodel = true, 1285 }; 1286 1287 static int __init imm_driver_init(void) 1288 { 1289 printk("imm: Version %s\n", IMM_VERSION); 1290 return parport_register_driver(&imm_driver); 1291 } 1292 1293 static void __exit imm_driver_exit(void) 1294 { 1295 parport_unregister_driver(&imm_driver); 1296 } 1297 1298 module_init(imm_driver_init); 1299 module_exit(imm_driver_exit); 1300 1301 MODULE_LICENSE("GPL"); 1302