1/* imm.c -- low level driver for the IOMEGA MatchMaker
2 * parallel port SCSI host adapter.
3 *
4 * (The IMM is the embedded controller in the ZIP Plus drive.)
5 *
6 * My unofficial company acronym list is 21 pages long:
7 * FLA: Four letter acronym with built in facility for
8 * future expansion to five letters.
9 */
10
11#include <linux/init.h>
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/blkdev.h>
15#include <linux/parport.h>
16#include <linux/workqueue.h>
17#include <linux/delay.h>
18#include <linux/slab.h>
19#include <asm/io.h>
20
21#include <scsi/scsi.h>
22#include <scsi/scsi_cmnd.h>
23#include <scsi/scsi_device.h>
24#include <scsi/scsi_host.h>
25
26/* The following #define is to avoid a clash with hosts.c */
27#define IMM_PROBE_SPP 0x0001
28#define IMM_PROBE_PS2 0x0002
29#define IMM_PROBE_ECR 0x0010
30#define IMM_PROBE_EPP17 0x0100
31#define IMM_PROBE_EPP19 0x0200
32
33
34typedef struct {
35 struct pardevice *dev; /* Parport device entry */
36 int base; /* Actual port address */
37 int base_hi; /* Hi Base address for ECP-ISA chipset */
38 int mode; /* Transfer mode */
39 struct scsi_cmnd *cur_cmd; /* Current queued command */
40 struct delayed_work imm_tq; /* Polling interrupt stuff */
41 unsigned long jstart; /* Jiffies at start */
42 unsigned failed:1; /* Failure flag */
43 unsigned dp:1; /* Data phase present */
44 unsigned rd:1; /* Read data in data phase */
45 unsigned wanted:1; /* Parport sharing busy flag */
46 unsigned int dev_no; /* Device number */
47 wait_queue_head_t *waiting;
48 struct Scsi_Host *host;
49 struct list_head list;
50} imm_struct;
51
52static void imm_reset_pulse(unsigned int base);
53static int device_check(imm_struct *dev);
54
55#include "imm.h"
56
57static inline imm_struct *imm_dev(struct Scsi_Host *host)
58{
59 return *(imm_struct **)&host->hostdata;
60}
61
62static DEFINE_SPINLOCK(arbitration_lock);
63
64static void got_it(imm_struct *dev)
65{
66 dev->base = dev->dev->port->base;
67 if (dev->cur_cmd)
68 dev->cur_cmd->SCp.phase = 1;
69 else
70 wake_up(dev->waiting);
71}
72
73static void imm_wakeup(void *ref)
74{
75 imm_struct *dev = (imm_struct *) ref;
76 unsigned long flags;
77
78 spin_lock_irqsave(&arbitration_lock, flags);
79 if (dev->wanted) {
80 if (parport_claim(dev->dev) == 0) {
81 got_it(dev);
82 dev->wanted = 0;
83 }
84 }
85 spin_unlock_irqrestore(&arbitration_lock, flags);
86}
87
88static int imm_pb_claim(imm_struct *dev)
89{
90 unsigned long flags;
91 int res = 1;
92 spin_lock_irqsave(&arbitration_lock, flags);
93 if (parport_claim(dev->dev) == 0) {
94 got_it(dev);
95 res = 0;
96 }
97 dev->wanted = res;
98 spin_unlock_irqrestore(&arbitration_lock, flags);
99 return res;
100}
101
102static void imm_pb_dismiss(imm_struct *dev)
103{
104 unsigned long flags;
105 int wanted;
106 spin_lock_irqsave(&arbitration_lock, flags);
107 wanted = dev->wanted;
108 dev->wanted = 0;
109 spin_unlock_irqrestore(&arbitration_lock, flags);
110 if (!wanted)
111 parport_release(dev->dev);
112}
113
114static inline void imm_pb_release(imm_struct *dev)
115{
116 parport_release(dev->dev);
117}
118
119/* This is to give the imm driver a way to modify the timings (and other
120 * parameters) by writing to the /proc/scsi/imm/0 file.
121 * Very simple method really... (Too 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 */
126static int imm_write_info(struct Scsi_Host *host, char *buffer, int length)
127{
128 imm_struct *dev = imm_dev(host);
129
130 if ((length > 5) && (strncmp(buffer, "mode=", 5) == 0)) {
131 dev->mode = simple_strtoul(buffer + 5, NULL, 0);
132 return length;
133 }
134 printk("imm /proc: invalid variable\n");
135 return -EINVAL;
136}
137
138static int imm_show_info(struct seq_file *m, struct Scsi_Host *host)
139{
140 imm_struct *dev = imm_dev(host);
141
142 seq_printf(m, "Version : %s\n", IMM_VERSION);
143 seq_printf(m, "Parport : %s\n", dev->dev->port->name);
144 seq_printf(m, "Mode : %s\n", IMM_MODE_STRING[dev->mode]);
145 return 0;
146}
147
148#if IMM_DEBUG > 0
149#define imm_fail(x,y) printk("imm: imm_fail(%i) from %s at line %d\n",\
150 y, __func__, __LINE__); imm_fail_func(x,y);
151static inline void
152imm_fail_func(imm_struct *dev, int error_code)
153#else
154static inline void
155imm_fail(imm_struct *dev, int error_code)
156#endif
157{
158 /* If we fail a device then we trash status / message bytes */
159 if (dev->cur_cmd) {
160 dev->cur_cmd->result = error_code << 16;
161 dev->failed = 1;
162 }
163}
164
165/*
166 * Wait for the high bit to be set.
167 *
168 * In principle, this could be tied to an interrupt, but the adapter
169 * doesn't appear to be designed to support interrupts. We spin on
170 * the 0x80 ready bit.
171 */
172static unsigned char imm_wait(imm_struct *dev)
173{
174 int k;
175 unsigned short ppb = dev->base;
176 unsigned char r;
177
178 w_ctr(ppb, 0x0c);
179
180 k = IMM_SPIN_TMO;
181 do {
182 r = r_str(ppb);
183 k--;
184 udelay(1);
185 }
186 while (!(r & 0x80) && (k));
187
188 /*
189 * STR register (LPT base+1) to SCSI mapping:
190 *
191 * STR imm imm
192 * ===================================
193 * 0x80 S_REQ S_REQ
194 * 0x40 !S_BSY (????)
195 * 0x20 !S_CD !S_CD
196 * 0x10 !S_IO !S_IO
197 * 0x08 (????) !S_BSY
198 *
199 * imm imm meaning
200 * ==================================
201 * 0xf0 0xb8 Bit mask
202 * 0xc0 0x88 ZIP wants more data
203 * 0xd0 0x98 ZIP wants to send more data
204 * 0xe0 0xa8 ZIP is expecting SCSI command data
205 * 0xf0 0xb8 end of transfer, ZIP is sending status
206 */
207 w_ctr(ppb, 0x04);
208 if (k)
209 return (r & 0xb8);
210
211 /* Counter expired - Time out occurred */
212 imm_fail(dev, DID_TIME_OUT);
213 printk("imm timeout in imm_wait\n");
214 return 0; /* command timed out */
215}
216
217static int imm_negotiate(imm_struct * tmp)
218{
219 /*
220 * The following is supposedly the IEEE 1284-1994 negotiate
221 * sequence. I have yet to obtain a copy of the above standard
222 * so this is a bit of a guess...
223 *
224 * A fair chunk of this is based on the Linux parport implementation
225 * of IEEE 1284.
226 *
227 * Return 0 if data available
228 * 1 if no data available
229 */
230
231 unsigned short base = tmp->base;
232 unsigned char a, mode;
233
234 switch (tmp->mode) {
235 case IMM_NIBBLE:
236 mode = 0x00;
237 break;
238 case IMM_PS2:
239 mode = 0x01;
240 break;
241 default:
242 return 0;
243 }
244
245 w_ctr(base, 0x04);
246 udelay(5);
247 w_dtr(base, mode);
248 udelay(100);
249 w_ctr(base, 0x06);
250 udelay(5);
251 a = (r_str(base) & 0x20) ? 0 : 1;
252 udelay(5);
253 w_ctr(base, 0x07);
254 udelay(5);
255 w_ctr(base, 0x06);
256
257 if (a) {
258 printk
259 ("IMM: IEEE1284 negotiate indicates no data available.\n");
260 imm_fail(tmp, DID_ERROR);
261 }
262 return a;
263}
264
265/*
266 * Clear EPP timeout bit.
267 */
268static inline void epp_reset(unsigned short ppb)
269{
270 int i;
271
272 i = r_str(ppb);
273 w_str(ppb, i);
274 w_str(ppb, i & 0xfe);
275}
276
277/*
278 * Wait for empty ECP fifo (if we are in ECP fifo mode only)
279 */
280static inline void ecp_sync(imm_struct *dev)
281{
282 int i, ppb_hi = dev->base_hi;
283
284 if (ppb_hi == 0)
285 return;
286
287 if ((r_ecr(ppb_hi) & 0xe0) == 0x60) { /* mode 011 == ECP fifo mode */
288 for (i = 0; i < 100; i++) {
289 if (r_ecr(ppb_hi) & 0x01)
290 return;
291 udelay(5);
292 }
293 printk("imm: ECP sync failed as data still present in FIFO.\n");
294 }
295}
296
297static int imm_byte_out(unsigned short base, const char *buffer, int len)
298{
299 int i;
300
301 w_ctr(base, 0x4); /* apparently a sane mode */
302 for (i = len >> 1; i; i--) {
303 w_dtr(base, *buffer++);
304 w_ctr(base, 0x5); /* Drop STROBE low */
305 w_dtr(base, *buffer++);
306 w_ctr(base, 0x0); /* STROBE high + INIT low */
307 }
308 w_ctr(base, 0x4); /* apparently a sane mode */
309 return 1; /* All went well - we hope! */
310}
311
312static int imm_nibble_in(unsigned short base, char *buffer, int len)
313{
314 unsigned char l;
315 int i;
316
317 /*
318 * The following is based on documented timing signals
319 */
320 w_ctr(base, 0x4);
321 for (i = len; i; i--) {
322 w_ctr(base, 0x6);
323 l = (r_str(base) & 0xf0) >> 4;
324 w_ctr(base, 0x5);
325 *buffer++ = (r_str(base) & 0xf0) | l;
326 w_ctr(base, 0x4);
327 }
328 return 1; /* All went well - we hope! */
329}
330
331static int imm_byte_in(unsigned short base, char *buffer, int len)
332{
333 int i;
334
335 /*
336 * The following is based on documented timing signals
337 */
338 w_ctr(base, 0x4);
339 for (i = len; i; i--) {
340 w_ctr(base, 0x26);
341 *buffer++ = r_dtr(base);
342 w_ctr(base, 0x25);
343 }
344 return 1; /* All went well - we hope! */
345}
346
347static int imm_out(imm_struct *dev, char *buffer, int len)
348{
349 unsigned short ppb = dev->base;
350 int r = imm_wait(dev);
351
352 /*
353 * Make sure that:
354 * a) the SCSI bus is BUSY (device still listening)
355 * b) the device is listening
356 */
357 if ((r & 0x18) != 0x08) {
358 imm_fail(dev, DID_ERROR);
359 printk("IMM: returned SCSI status %2x\n", r);
360 return 0;
361 }
362 switch (dev->mode) {
363 case IMM_EPP_32:
364 case IMM_EPP_16:
365 case IMM_EPP_8:
366 epp_reset(ppb);
367 w_ctr(ppb, 0x4);
368#ifdef CONFIG_SCSI_IZIP_EPP16
369 if (!(((long) buffer | len) & 0x01))
370 outsw(ppb + 4, buffer, len >> 1);
371#else
372 if (!(((long) buffer | len) & 0x03))
373 outsl(ppb + 4, buffer, len >> 2);
374#endif
375 else
376 outsb(ppb + 4, buffer, len);
377 w_ctr(ppb, 0xc);
378 r = !(r_str(ppb) & 0x01);
379 w_ctr(ppb, 0xc);
380 ecp_sync(dev);
381 break;
382
383 case IMM_NIBBLE:
384 case IMM_PS2:
385 /* 8 bit output, with a loop */
386 r = imm_byte_out(ppb, buffer, len);
387 break;
388
389 default:
390 printk("IMM: bug in imm_out()\n");
391 r = 0;
392 }
393 return r;
394}
395
396static int imm_in(imm_struct *dev, char *buffer, int len)
397{
398 unsigned short ppb = dev->base;
399 int r = imm_wait(dev);
400
401 /*
402 * Make sure that:
403 * a) the SCSI bus is BUSY (device still listening)
404 * b) the device is sending data
405 */
406 if ((r & 0x18) != 0x18) {
407 imm_fail(dev, DID_ERROR);
408 return 0;
409 }
410 switch (dev->mode) {
411 case IMM_NIBBLE:
412 /* 4 bit input, with a loop */
413 r = imm_nibble_in(ppb, buffer, len);
414 w_ctr(ppb, 0xc);
415 break;
416
417 case IMM_PS2:
418 /* 8 bit input, with a loop */
419 r = imm_byte_in(ppb, buffer, len);
420 w_ctr(ppb, 0xc);
421 break;
422
423 case IMM_EPP_32:
424 case IMM_EPP_16:
425 case IMM_EPP_8:
426 epp_reset(ppb);
427 w_ctr(ppb, 0x24);
428#ifdef CONFIG_SCSI_IZIP_EPP16
429 if (!(((long) buffer | len) & 0x01))
430 insw(ppb + 4, buffer, len >> 1);
431#else
432 if (!(((long) buffer | len) & 0x03))
433 insl(ppb + 4, buffer, len >> 2);
434#endif
435 else
436 insb(ppb + 4, buffer, len);
437 w_ctr(ppb, 0x2c);
438 r = !(r_str(ppb) & 0x01);
439 w_ctr(ppb, 0x2c);
440 ecp_sync(dev);
441 break;
442
443 default:
444 printk("IMM: bug in imm_ins()\n");
445 r = 0;
446 break;
447 }
448 return r;
449}
450
451static int imm_cpp(unsigned short ppb, unsigned char b)
452{
453 /*
454 * Comments on udelay values refer to the
455 * Command Packet Protocol (CPP) timing diagram.
456 */
457
458 unsigned char s1, s2, s3;
459 w_ctr(ppb, 0x0c);
460 udelay(2); /* 1 usec - infinite */
461 w_dtr(ppb, 0xaa);
462 udelay(10); /* 7 usec - infinite */
463 w_dtr(ppb, 0x55);
464 udelay(10); /* 7 usec - infinite */
465 w_dtr(ppb, 0x00);
466 udelay(10); /* 7 usec - infinite */
467 w_dtr(ppb, 0xff);
468 udelay(10); /* 7 usec - infinite */
469 s1 = r_str(ppb) & 0xb8;
470 w_dtr(ppb, 0x87);
471 udelay(10); /* 7 usec - infinite */
472 s2 = r_str(ppb) & 0xb8;
473 w_dtr(ppb, 0x78);
474 udelay(10); /* 7 usec - infinite */
475 s3 = r_str(ppb) & 0x38;
476 /*
477 * Values for b are:
478 * 0000 00aa Assign address aa to current device
479 * 0010 00aa Select device aa in EPP Winbond mode
480 * 0010 10aa Select device aa in EPP mode
481 * 0011 xxxx Deselect all devices
482 * 0110 00aa Test device aa
483 * 1101 00aa Select device aa in ECP mode
484 * 1110 00aa Select device aa in Compatible mode
485 */
486 w_dtr(ppb, b);
487 udelay(2); /* 1 usec - infinite */
488 w_ctr(ppb, 0x0c);
489 udelay(10); /* 7 usec - infinite */
490 w_ctr(ppb, 0x0d);
491 udelay(2); /* 1 usec - infinite */
492 w_ctr(ppb, 0x0c);
493 udelay(10); /* 7 usec - infinite */
494 w_dtr(ppb, 0xff);
495 udelay(10); /* 7 usec - infinite */
496
497 /*
498 * The following table is electrical pin values.
499 * (BSY is inverted at the CTR register)
500 *
501 * BSY ACK POut SEL Fault
502 * S1 0 X 1 1 1
503 * S2 1 X 0 1 1
504 * S3 L X 1 1 S
505 *
506 * L => Last device in chain
507 * S => Selected
508 *
509 * Observered values for S1,S2,S3 are:
510 * Disconnect => f8/58/78
511 * Connect => f8/58/70
512 */
513 if ((s1 == 0xb8) && (s2 == 0x18) && (s3 == 0x30))
514 return 1; /* Connected */
515 if ((s1 == 0xb8) && (s2 == 0x18) && (s3 == 0x38))
516 return 0; /* Disconnected */
517
518 return -1; /* No device present */
519}
520
521static inline int imm_connect(imm_struct *dev, int flag)
522{
523 unsigned short ppb = dev->base;
524
525 imm_cpp(ppb, 0xe0); /* Select device 0 in compatible mode */
526 imm_cpp(ppb, 0x30); /* Disconnect all devices */
527
528 if ((dev->mode == IMM_EPP_8) ||
529 (dev->mode == IMM_EPP_16) ||
530 (dev->mode == IMM_EPP_32))
531 return imm_cpp(ppb, 0x28); /* Select device 0 in EPP mode */
532 return imm_cpp(ppb, 0xe0); /* Select device 0 in compatible mode */
533}
534
535static void imm_disconnect(imm_struct *dev)
536{
537 imm_cpp(dev->base, 0x30); /* Disconnect all devices */
538}
539
540static int imm_select(imm_struct *dev, int target)
541{
542 int k;
543 unsigned short ppb = dev->base;
544
545 /*
546 * Firstly we want to make sure there is nothing
547 * holding onto the SCSI bus.
548 */
549 w_ctr(ppb, 0xc);
550
551 k = IMM_SELECT_TMO;
552 do {
553 k--;
554 } while ((r_str(ppb) & 0x08) && (k));
555
556 if (!k)
557 return 0;
558
559 /*
560 * Now assert the SCSI ID (HOST and TARGET) on the data bus
561 */
562 w_ctr(ppb, 0x4);
563 w_dtr(ppb, 0x80 | (1 << target));
564 udelay(1);
565
566 /*
567 * Deassert SELIN first followed by STROBE
568 */
569 w_ctr(ppb, 0xc);
570 w_ctr(ppb, 0xd);
571
572 /*
573 * ACK should drop low while SELIN is deasserted.
574 * FAULT should drop low when the SCSI device latches the bus.
575 */
576 k = IMM_SELECT_TMO;
577 do {
578 k--;
579 }
580 while (!(r_str(ppb) & 0x08) && (k));
581
582 /*
583 * Place the interface back into a sane state (status mode)
584 */
585 w_ctr(ppb, 0xc);
586 return (k) ? 1 : 0;
587}
588
589static int imm_init(imm_struct *dev)
590{
591 if (imm_connect(dev, 0) != 1)
592 return -EIO;
593 imm_reset_pulse(dev->base);
594 mdelay(1); /* Delay to allow devices to settle */
595 imm_disconnect(dev);
596 mdelay(1); /* Another delay to allow devices to settle */
597 return device_check(dev);
598}
599
600static inline int imm_send_command(struct scsi_cmnd *cmd)
601{
602 imm_struct *dev = imm_dev(cmd->device->host);
603 int k;
604
605 /* NOTE: IMM uses byte pairs */
606 for (k = 0; k < cmd->cmd_len; k += 2)
607 if (!imm_out(dev, &cmd->cmnd[k], 2))
608 return 0;
609 return 1;
610}
611
612/*
613 * The bulk flag enables some optimisations in the data transfer loops,
614 * it should be true for any command that transfers data in integral
615 * numbers of sectors.
616 *
617 * The driver appears to remain stable if we speed up the parallel port
618 * i/o in this function, but not elsewhere.
619 */
620static int imm_completion(struct scsi_cmnd *cmd)
621{
622 /* Return codes:
623 * -1 Error
624 * 0 Told to schedule
625 * 1 Finished data transfer
626 */
627 imm_struct *dev = imm_dev(cmd->device->host);
628 unsigned short ppb = dev->base;
629 unsigned long start_jiffies = jiffies;
630
631 unsigned char r, v;
632 int fast, bulk, status;
633
634 v = cmd->cmnd[0];
635 bulk = ((v == READ_6) ||
636 (v == READ_10) || (v == WRITE_6) || (v == WRITE_10));
637
638 /*
639 * We only get here if the drive is ready to comunicate,
640 * hence no need for a full imm_wait.
641 */
642 w_ctr(ppb, 0x0c);
643 r = (r_str(ppb) & 0xb8);
644
645 /*
646 * while (device is not ready to send status byte)
647 * loop;
648 */
649 while (r != (unsigned char) 0xb8) {
650 /*
651 * If we have been running for more than a full timer tick
652 * then take a rest.
653 */
654 if (time_after(jiffies, start_jiffies + 1))
655 return 0;
656
657 /*
658 * FAIL if:
659 * a) Drive status is screwy (!ready && !present)
660 * b) Drive is requesting/sending more data than expected
661 */
662 if (((r & 0x88) != 0x88) || (cmd->SCp.this_residual <= 0)) {
663 imm_fail(dev, DID_ERROR);
664 return -1; /* ERROR_RETURN */
665 }
666 /* determine if we should use burst I/O */
667 if (dev->rd == 0) {
668 fast = (bulk
669 && (cmd->SCp.this_residual >=
670 IMM_BURST_SIZE)) ? IMM_BURST_SIZE : 2;
671 status = imm_out(dev, cmd->SCp.ptr, fast);
672 } else {
673 fast = (bulk
674 && (cmd->SCp.this_residual >=
675 IMM_BURST_SIZE)) ? IMM_BURST_SIZE : 1;
676 status = imm_in(dev, cmd->SCp.ptr, fast);
677 }
678
679 cmd->SCp.ptr += fast;
680 cmd->SCp.this_residual -= fast;
681
682 if (!status) {
683 imm_fail(dev, DID_BUS_BUSY);
684 return -1; /* ERROR_RETURN */
685 }
686 if (cmd->SCp.buffer && !cmd->SCp.this_residual) {
687 /* if scatter/gather, advance to the next segment */
688 if (cmd->SCp.buffers_residual--) {
689 cmd->SCp.buffer++;
690 cmd->SCp.this_residual =
691 cmd->SCp.buffer->length;
692 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
693
694 /*
695 * Make sure that we transfer even number of bytes
696 * otherwise it makes imm_byte_out() messy.
697 */
698 if (cmd->SCp.this_residual & 0x01)
699 cmd->SCp.this_residual++;
700 }
701 }
702 /* Now check to see if the drive is ready to comunicate */
703 w_ctr(ppb, 0x0c);
704 r = (r_str(ppb) & 0xb8);
705
706 /* If not, drop back down to the scheduler and wait a timer tick */
707 if (!(r & 0x80))
708 return 0;
709 }
710 return 1; /* FINISH_RETURN */
711}
712
713/*
714 * Since the IMM itself doesn't generate interrupts, we use
715 * the scheduler's task queue to generate a stream of call-backs and
716 * complete the request when the drive is ready.
717 */
718static void imm_interrupt(struct work_struct *work)
719{
720 imm_struct *dev = container_of(work, imm_struct, imm_tq.work);
721 struct scsi_cmnd *cmd = dev->cur_cmd;
722 struct Scsi_Host *host = cmd->device->host;
723 unsigned long flags;
724
725 if (imm_engine(dev, cmd)) {
726 schedule_delayed_work(&dev->imm_tq, 1);
727 return;
728 }
729 /* Command must of completed hence it is safe to let go... */
730#if IMM_DEBUG > 0
731 switch ((cmd->result >> 16) & 0xff) {
732 case DID_OK:
733 break;
734 case DID_NO_CONNECT:
735 printk("imm: no device at SCSI ID %i\n", cmd->device->id);
736 break;
737 case DID_BUS_BUSY:
738 printk("imm: BUS BUSY - EPP timeout detected\n");
739 break;
740 case DID_TIME_OUT:
741 printk("imm: unknown timeout\n");
742 break;
743 case DID_ABORT:
744 printk("imm: told to abort\n");
745 break;
746 case DID_PARITY:
747 printk("imm: parity error (???)\n");
748 break;
749 case DID_ERROR:
750 printk("imm: internal driver error\n");
751 break;
752 case DID_RESET:
753 printk("imm: told to reset device\n");
754 break;
755 case DID_BAD_INTR:
756 printk("imm: bad interrupt (???)\n");
757 break;
758 default:
759 printk("imm: bad return code (%02x)\n",
760 (cmd->result >> 16) & 0xff);
761 }
762#endif
763
764 if (cmd->SCp.phase > 1)
765 imm_disconnect(dev);
766
767 imm_pb_dismiss(dev);
768
769 spin_lock_irqsave(host->host_lock, flags);
770 dev->cur_cmd = NULL;
771 cmd->scsi_done(cmd);
772 spin_unlock_irqrestore(host->host_lock, flags);
773 return;
774}
775
776static int imm_engine(imm_struct *dev, struct scsi_cmnd *cmd)
777{
778 unsigned short ppb = dev->base;
779 unsigned char l = 0, h = 0;
780 int retv, x;
781
782 /* First check for any errors that may have occurred
783 * Here we check for internal errors
784 */
785 if (dev->failed)
786 return 0;
787
788 switch (cmd->SCp.phase) {
789 case 0: /* Phase 0 - Waiting for parport */
790 if (time_after(jiffies, dev->jstart + HZ)) {
791 /*
792 * We waited more than a second
793 * for parport to call us
794 */
795 imm_fail(dev, DID_BUS_BUSY);
796 return 0;
797 }
798 return 1; /* wait until imm_wakeup claims parport */
799 /* Phase 1 - Connected */
800 case 1:
801 imm_connect(dev, CONNECT_EPP_MAYBE);
802 cmd->SCp.phase++;
803
804 /* Phase 2 - We are now talking to the scsi bus */
805 case 2:
806 if (!imm_select(dev, scmd_id(cmd))) {
807 imm_fail(dev, DID_NO_CONNECT);
808 return 0;
809 }
810 cmd->SCp.phase++;
811
812 /* Phase 3 - Ready to accept a command */
813 case 3:
814 w_ctr(ppb, 0x0c);
815 if (!(r_str(ppb) & 0x80))
816 return 1;
817
818 if (!imm_send_command(cmd))
819 return 0;
820 cmd->SCp.phase++;
821
822 /* Phase 4 - Setup scatter/gather buffers */
823 case 4:
824 if (scsi_bufflen(cmd)) {
825 cmd->SCp.buffer = scsi_sglist(cmd);
826 cmd->SCp.this_residual = cmd->SCp.buffer->length;
827 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
828 } else {
829 cmd->SCp.buffer = NULL;
830 cmd->SCp.this_residual = 0;
831 cmd->SCp.ptr = NULL;
832 }
833 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
834 cmd->SCp.phase++;
835 if (cmd->SCp.this_residual & 0x01)
836 cmd->SCp.this_residual++;
837 /* Phase 5 - Pre-Data transfer stage */
838 case 5:
839 /* Spin lock for BUSY */
840 w_ctr(ppb, 0x0c);
841 if (!(r_str(ppb) & 0x80))
842 return 1;
843
844 /* Require negotiation for read requests */
845 x = (r_str(ppb) & 0xb8);
846 dev->rd = (x & 0x10) ? 1 : 0;
847 dev->dp = (x & 0x20) ? 0 : 1;
848
849 if ((dev->dp) && (dev->rd))
850 if (imm_negotiate(dev))
851 return 0;
852 cmd->SCp.phase++;
853
854 /* Phase 6 - Data transfer stage */
855 case 6:
856 /* Spin lock for BUSY */
857 w_ctr(ppb, 0x0c);
858 if (!(r_str(ppb) & 0x80))
859 return 1;
860
861 if (dev->dp) {
862 retv = imm_completion(cmd);
863 if (retv == -1)
864 return 0;
865 if (retv == 0)
866 return 1;
867 }
868 cmd->SCp.phase++;
869
870 /* Phase 7 - Post data transfer stage */
871 case 7:
872 if ((dev->dp) && (dev->rd)) {
873 if ((dev->mode == IMM_NIBBLE) || (dev->mode == IMM_PS2)) {
874 w_ctr(ppb, 0x4);
875 w_ctr(ppb, 0xc);
876 w_ctr(ppb, 0xe);
877 w_ctr(ppb, 0x4);
878 }
879 }
880 cmd->SCp.phase++;
881
882 /* Phase 8 - Read status/message */
883 case 8:
884 /* Check for data overrun */
885 if (imm_wait(dev) != (unsigned char) 0xb8) {
886 imm_fail(dev, DID_ERROR);
887 return 0;
888 }
889 if (imm_negotiate(dev))
890 return 0;
891 if (imm_in(dev, &l, 1)) { /* read status byte */
892 /* Check for optional message byte */
893 if (imm_wait(dev) == (unsigned char) 0xb8)
894 imm_in(dev, &h, 1);
895 cmd->result = (DID_OK << 16) | (l & STATUS_MASK);
896 }
897 if ((dev->mode == IMM_NIBBLE) || (dev->mode == IMM_PS2)) {
898 w_ctr(ppb, 0x4);
899 w_ctr(ppb, 0xc);
900 w_ctr(ppb, 0xe);
901 w_ctr(ppb, 0x4);
902 }
903 return 0; /* Finished */
904 break;
905
906 default:
907 printk("imm: Invalid scsi phase\n");
908 }
909 return 0;
910}
911
912static int imm_queuecommand_lck(struct scsi_cmnd *cmd,
913 void (*done)(struct scsi_cmnd *))
914{
915 imm_struct *dev = imm_dev(cmd->device->host);
916
917 if (dev->cur_cmd) {
918 printk("IMM: bug in imm_queuecommand\n");
919 return 0;
920 }
921 dev->failed = 0;
922 dev->jstart = jiffies;
923 dev->cur_cmd = cmd;
924 cmd->scsi_done = done;
925 cmd->result = DID_ERROR << 16; /* default return code */
926 cmd->SCp.phase = 0; /* bus free */
927
928 schedule_delayed_work(&dev->imm_tq, 0);
929
930 imm_pb_claim(dev);
931
932 return 0;
933}
934
935static DEF_SCSI_QCMD(imm_queuecommand)
936
937/*
938 * Apparently the disk->capacity attribute is off by 1 sector
939 * for all disk drives. We add the one here, but it should really
940 * be done in sd.c. Even if it gets fixed there, this will still
941 * work.
942 */
943static int imm_biosparam(struct scsi_device *sdev, struct block_device *dev,
944 sector_t capacity, int ip[])
945{
946 ip[0] = 0x40;
947 ip[1] = 0x20;
948 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]);
949 if (ip[2] > 1024) {
950 ip[0] = 0xff;
951 ip[1] = 0x3f;
952 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]);
953 }
954 return 0;
955}
956
957static int imm_abort(struct scsi_cmnd *cmd)
958{
959 imm_struct *dev = imm_dev(cmd->device->host);
960 /*
961 * There is no method for aborting commands since Iomega
962 * have tied the SCSI_MESSAGE line high in the interface
963 */
964
965 switch (cmd->SCp.phase) {
966 case 0: /* Do not have access to parport */
967 case 1: /* Have not connected to interface */
968 dev->cur_cmd = NULL; /* Forget the problem */
969 return SUCCESS;
970 break;
971 default: /* SCSI command sent, can not abort */
972 return FAILED;
973 break;
974 }
975}
976
977static void imm_reset_pulse(unsigned int base)
978{
979 w_ctr(base, 0x04);
980 w_dtr(base, 0x40);
981 udelay(1);
982 w_ctr(base, 0x0c);
983 w_ctr(base, 0x0d);
984 udelay(50);
985 w_ctr(base, 0x0c);
986 w_ctr(base, 0x04);
987}
988
989static int imm_reset(struct scsi_cmnd *cmd)
990{
991 imm_struct *dev = imm_dev(cmd->device->host);
992
993 if (cmd->SCp.phase)
994 imm_disconnect(dev);
995 dev->cur_cmd = NULL; /* Forget the problem */
996
997 imm_connect(dev, CONNECT_NORMAL);
998 imm_reset_pulse(dev->base);
999 mdelay(1); /* device settle delay */
1000 imm_disconnect(dev);
1001 mdelay(1); /* device settle delay */
1002 return SUCCESS;
1003}
1004
1005static int device_check(imm_struct *dev)
1006{
1007 /* This routine looks for a device and then attempts to use EPP
1008 to send a command. If all goes as planned then EPP is available. */
1009
1010 static char cmd[6] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
1011 int loop, old_mode, status, k, ppb = dev->base;
1012 unsigned char l;
1013
1014 old_mode = dev->mode;
1015 for (loop = 0; loop < 8; loop++) {
1016 /* Attempt to use EPP for Test Unit Ready */
1017 if ((ppb & 0x0007) == 0x0000)
1018 dev->mode = IMM_EPP_32;
1019
1020 second_pass:
1021 imm_connect(dev, CONNECT_EPP_MAYBE);
1022 /* Select SCSI device */
1023 if (!imm_select(dev, loop)) {
1024 imm_disconnect(dev);
1025 continue;
1026 }
1027 printk("imm: Found device at ID %i, Attempting to use %s\n",
1028 loop, IMM_MODE_STRING[dev->mode]);
1029
1030 /* Send SCSI command */
1031 status = 1;
1032 w_ctr(ppb, 0x0c);
1033 for (l = 0; (l < 3) && (status); l++)
1034 status = imm_out(dev, &cmd[l << 1], 2);
1035
1036 if (!status) {
1037 imm_disconnect(dev);
1038 imm_connect(dev, CONNECT_EPP_MAYBE);
1039 imm_reset_pulse(dev->base);
1040 udelay(1000);
1041 imm_disconnect(dev);
1042 udelay(1000);
1043 if (dev->mode == IMM_EPP_32) {
1044 dev->mode = old_mode;
1045 goto second_pass;
1046 }
1047 printk("imm: Unable to establish communication\n");
1048 return -EIO;
1049 }
1050 w_ctr(ppb, 0x0c);
1051
1052 k = 1000000; /* 1 Second */
1053 do {
1054 l = r_str(ppb);
1055 k--;
1056 udelay(1);
1057 } while (!(l & 0x80) && (k));
1058
1059 l &= 0xb8;
1060
1061 if (l != 0xb8) {
1062 imm_disconnect(dev);
1063 imm_connect(dev, CONNECT_EPP_MAYBE);
1064 imm_reset_pulse(dev->base);
1065 udelay(1000);
1066 imm_disconnect(dev);
1067 udelay(1000);
1068 if (dev->mode == IMM_EPP_32) {
1069 dev->mode = old_mode;
1070 goto second_pass;
1071 }
1072 printk
1073 ("imm: Unable to establish communication\n");
1074 return -EIO;
1075 }
1076 imm_disconnect(dev);
1077 printk
1078 ("imm: Communication established at 0x%x with ID %i using %s\n",
1079 ppb, loop, IMM_MODE_STRING[dev->mode]);
1080 imm_connect(dev, CONNECT_EPP_MAYBE);
1081 imm_reset_pulse(dev->base);
1082 udelay(1000);
1083 imm_disconnect(dev);
1084 udelay(1000);
1085 return 0;
1086 }
1087 printk("imm: No devices found\n");
1088 return -ENODEV;
1089}
1090
1091/*
1092 * imm cannot deal with highmem, so this causes all IO pages for this host
1093 * to reside in low memory (hence mapped)
1094 */
1095static int imm_adjust_queue(struct scsi_device *device)
1096{
1097 blk_queue_bounce_limit(device->request_queue, BLK_BOUNCE_HIGH);
1098 return 0;
1099}
1100
1101static struct scsi_host_template imm_template = {
1102 .module = THIS_MODULE,
1103 .proc_name = "imm",
1104 .show_info = imm_show_info,
1105 .write_info = imm_write_info,
1106 .name = "Iomega VPI2 (imm) interface",
1107 .queuecommand = imm_queuecommand,
1108 .eh_abort_handler = imm_abort,
1109 .eh_host_reset_handler = imm_reset,
1110 .bios_param = imm_biosparam,
1111 .this_id = 7,
1112 .sg_tablesize = SG_ALL,
1113 .can_queue = 1,
1114 .slave_alloc = imm_adjust_queue,
1115};
1116
1117/***************************************************************************
1118 * Parallel port probing routines *
1119 ***************************************************************************/
1120
1121static LIST_HEAD(imm_hosts);
1122
1123/*
1124 * Finds the first available device number that can be alloted to the
1125 * new imm device and returns the address of the previous node so that
1126 * we can add to the tail and have a list in the ascending order.
1127 */
1128
1129static inline imm_struct *find_parent(void)
1130{
1131 imm_struct *dev, *par = NULL;
1132 unsigned int cnt = 0;
1133
1134 if (list_empty(&imm_hosts))
1135 return NULL;
1136
1137 list_for_each_entry(dev, &imm_hosts, list) {
1138 if (dev->dev_no != cnt)
1139 return par;
1140 cnt++;
1141 par = dev;
1142 }
1143
1144 return par;
1145}
1146
1147static int __imm_attach(struct parport *pb)
1148{
1149 struct Scsi_Host *host;
1150 imm_struct *dev, *temp;
1151 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(waiting);
1152 DEFINE_WAIT(wait);
1153 int ports;
1154 int modes, ppb;
1155 int err = -ENOMEM;
1156 struct pardev_cb imm_cb;
1157
1158 init_waitqueue_head(&waiting);
1159
1160 dev = kzalloc(sizeof(imm_struct), GFP_KERNEL);
1161 if (!dev)
1162 return -ENOMEM;
1163
1164
1165 dev->base = -1;
1166 dev->mode = IMM_AUTODETECT;
1167 INIT_LIST_HEAD(&dev->list);
1168
1169 temp = find_parent();
1170 if (temp)
1171 dev->dev_no = temp->dev_no + 1;
1172
1173 memset(&imm_cb, 0, sizeof(imm_cb));
1174 imm_cb.private = dev;
1175 imm_cb.wakeup = imm_wakeup;
1176
1177 dev->dev = parport_register_dev_model(pb, "imm", &imm_cb, dev->dev_no);
1178 if (!dev->dev)
1179 goto out;
1180
1181
1182 /* Claim the bus so it remembers what we do to the control
1183 * registers. [ CTR and ECP ]
1184 */
1185 err = -EBUSY;
1186 dev->waiting = &waiting;
1187 prepare_to_wait(&waiting, &wait, TASK_UNINTERRUPTIBLE);
1188 if (imm_pb_claim(dev))
1189 schedule_timeout(3 * HZ);
1190 if (dev->wanted) {
1191 printk(KERN_ERR "imm%d: failed to claim parport because "
1192 "a pardevice is owning the port for too long "
1193 "time!\n", pb->number);
1194 imm_pb_dismiss(dev);
1195 dev->waiting = NULL;
1196 finish_wait(&waiting, &wait);
1197 goto out1;
1198 }
1199 dev->waiting = NULL;
1200 finish_wait(&waiting, &wait);
1201 ppb = dev->base = dev->dev->port->base;
1202 dev->base_hi = dev->dev->port->base_hi;
1203 w_ctr(ppb, 0x0c);
1204 modes = dev->dev->port->modes;
1205
1206 /* Mode detection works up the chain of speed
1207 * This avoids a nasty if-then-else-if-... tree
1208 */
1209 dev->mode = IMM_NIBBLE;
1210
1211 if (modes & PARPORT_MODE_TRISTATE)
1212 dev->mode = IMM_PS2;
1213
1214 /* Done configuration */
1215
1216 err = imm_init(dev);
1217
1218 imm_pb_release(dev);
1219
1220 if (err)
1221 goto out1;
1222
1223 /* now the glue ... */
1224 if (dev->mode == IMM_NIBBLE || dev->mode == IMM_PS2)
1225 ports = 3;
1226 else
1227 ports = 8;
1228
1229 INIT_DELAYED_WORK(&dev->imm_tq, imm_interrupt);
1230
1231 err = -ENOMEM;
1232 host = scsi_host_alloc(&imm_template, sizeof(imm_struct *));
1233 if (!host)
1234 goto out1;
1235 host->io_port = pb->base;
1236 host->n_io_port = ports;
1237 host->dma_channel = -1;
1238 host->unique_id = pb->number;
1239 *(imm_struct **)&host->hostdata = dev;
1240 dev->host = host;
1241 if (!temp)
1242 list_add_tail(&dev->list, &imm_hosts);
1243 else
1244 list_add_tail(&dev->list, &temp->list);
1245 err = scsi_add_host(host, NULL);
1246 if (err)
1247 goto out2;
1248 scsi_scan_host(host);
1249 return 0;
1250
1251out2:
1252 list_del_init(&dev->list);
1253 scsi_host_put(host);
1254out1:
1255 parport_unregister_device(dev->dev);
1256out:
1257 kfree(dev);
1258 return err;
1259}
1260
1261static void imm_attach(struct parport *pb)
1262{
1263 __imm_attach(pb);
1264}
1265
1266static void imm_detach(struct parport *pb)
1267{
1268 imm_struct *dev;
1269 list_for_each_entry(dev, &imm_hosts, list) {
1270 if (dev->dev->port == pb) {
1271 list_del_init(&dev->list);
1272 scsi_remove_host(dev->host);
1273 scsi_host_put(dev->host);
1274 parport_unregister_device(dev->dev);
1275 kfree(dev);
1276 break;
1277 }
1278 }
1279}
1280
1281static struct parport_driver imm_driver = {
1282 .name = "imm",
1283 .match_port = imm_attach,
1284 .detach = imm_detach,
1285 .devmodel = true,
1286};
1287
1288static int __init imm_driver_init(void)
1289{
1290 printk("imm: Version %s\n", IMM_VERSION);
1291 return parport_register_driver(&imm_driver);
1292}
1293
1294static void __exit imm_driver_exit(void)
1295{
1296 parport_unregister_driver(&imm_driver);
1297}
1298
1299module_init(imm_driver_init);
1300module_exit(imm_driver_exit);
1301
1302MODULE_LICENSE("GPL");
1303