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
35typedef 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
53static void imm_reset_pulse(unsigned int base);
54static int device_check(imm_struct *dev, bool autodetect);
55
56#include "imm.h"
57
58static unsigned int mode = IMM_AUTODETECT;
59module_param(mode, uint, 0644);
60MODULE_PARM_DESC(mode, "Transfer mode (0 = Autodetect, 1 = SPP 4-bit, "
61 "2 = SPP 8-bit, 3 = EPP 8-bit, 4 = EPP 16-bit, 5 = EPP 32-bit");
62
63static inline imm_struct *imm_dev(struct Scsi_Host *host)
64{
65 return *(imm_struct **)&host->hostdata;
66}
67
68static DEFINE_SPINLOCK(arbitration_lock);
69
70static void got_it(imm_struct *dev)
71{
72 dev->base = dev->dev->port->base;
73 if (dev->cur_cmd)
74 imm_scsi_pointer(cmd: dev->cur_cmd)->phase = 1;
75 else
76 wake_up(dev->waiting);
77}
78
79static void imm_wakeup(void *ref)
80{
81 imm_struct *dev = (imm_struct *) ref;
82 unsigned long flags;
83
84 spin_lock_irqsave(&arbitration_lock, flags);
85 if (dev->wanted) {
86 if (parport_claim(dev: dev->dev) == 0) {
87 got_it(dev);
88 dev->wanted = 0;
89 }
90 }
91 spin_unlock_irqrestore(lock: &arbitration_lock, flags);
92}
93
94static int imm_pb_claim(imm_struct *dev)
95{
96 unsigned long flags;
97 int res = 1;
98 spin_lock_irqsave(&arbitration_lock, flags);
99 if (parport_claim(dev: dev->dev) == 0) {
100 got_it(dev);
101 res = 0;
102 }
103 dev->wanted = res;
104 spin_unlock_irqrestore(lock: &arbitration_lock, flags);
105 return res;
106}
107
108static void imm_pb_dismiss(imm_struct *dev)
109{
110 unsigned long flags;
111 int wanted;
112 spin_lock_irqsave(&arbitration_lock, flags);
113 wanted = dev->wanted;
114 dev->wanted = 0;
115 spin_unlock_irqrestore(lock: &arbitration_lock, flags);
116 if (!wanted)
117 parport_release(dev: dev->dev);
118}
119
120static inline void imm_pb_release(imm_struct *dev)
121{
122 parport_release(dev: dev->dev);
123}
124
125/* This is to give the imm driver a way to modify the timings (and other
126 * parameters) by writing to the /proc/scsi/imm/0 file.
127 * Very simple method really... (Too simple, no error checking :( )
128 * Reason: Kernel hackers HATE having to unload and reload modules for
129 * testing...
130 * Also gives a method to use a script to obtain optimum timings (TODO)
131 */
132static int imm_write_info(struct Scsi_Host *host, char *buffer, int length)
133{
134 imm_struct *dev = imm_dev(host);
135
136 if ((length > 5) && (strncmp(buffer, "mode=", 5) == 0)) {
137 dev->mode = simple_strtoul(buffer + 5, NULL, 0);
138 return length;
139 }
140 printk("imm /proc: invalid variable\n");
141 return -EINVAL;
142}
143
144static int imm_show_info(struct seq_file *m, struct Scsi_Host *host)
145{
146 imm_struct *dev = imm_dev(host);
147
148 seq_printf(m, fmt: "Version : %s\n", IMM_VERSION);
149 seq_printf(m, fmt: "Parport : %s\n", dev->dev->port->name);
150 seq_printf(m, fmt: "Mode : %s\n", IMM_MODE_STRING[dev->mode]);
151 return 0;
152}
153
154#if IMM_DEBUG > 0
155#define imm_fail(x,y) printk("imm: imm_fail(%i) from %s at line %d\n",\
156 y, __func__, __LINE__); imm_fail_func(x,y);
157static inline void
158imm_fail_func(imm_struct *dev, int error_code)
159#else
160static inline void
161imm_fail(imm_struct *dev, int error_code)
162#endif
163{
164 /* If we fail a device then we trash status / message bytes */
165 if (dev->cur_cmd) {
166 dev->cur_cmd->result = error_code << 16;
167 dev->failed = 1;
168 }
169}
170
171/*
172 * Wait for the high bit to be set.
173 *
174 * In principle, this could be tied to an interrupt, but the adapter
175 * doesn't appear to be designed to support interrupts. We spin on
176 * the 0x80 ready bit.
177 */
178static unsigned char imm_wait(imm_struct *dev)
179{
180 int k;
181 unsigned short ppb = dev->base;
182 unsigned char r;
183
184 w_ctr(ppb, 0x0c);
185
186 k = IMM_SPIN_TMO;
187 do {
188 r = r_str(ppb);
189 k--;
190 udelay(1);
191 }
192 while (!(r & 0x80) && (k));
193
194 /*
195 * STR register (LPT base+1) to SCSI mapping:
196 *
197 * STR imm imm
198 * ===================================
199 * 0x80 S_REQ S_REQ
200 * 0x40 !S_BSY (????)
201 * 0x20 !S_CD !S_CD
202 * 0x10 !S_IO !S_IO
203 * 0x08 (????) !S_BSY
204 *
205 * imm imm meaning
206 * ==================================
207 * 0xf0 0xb8 Bit mask
208 * 0xc0 0x88 ZIP wants more data
209 * 0xd0 0x98 ZIP wants to send more data
210 * 0xe0 0xa8 ZIP is expecting SCSI command data
211 * 0xf0 0xb8 end of transfer, ZIP is sending status
212 */
213 w_ctr(ppb, 0x04);
214 if (k)
215 return (r & 0xb8);
216
217 /* Counter expired - Time out occurred */
218 imm_fail(dev, error_code: DID_TIME_OUT);
219 printk("imm timeout in imm_wait\n");
220 return 0; /* command timed out */
221}
222
223static int imm_negotiate(imm_struct * tmp)
224{
225 /*
226 * The following is supposedly the IEEE 1284-1994 negotiate
227 * sequence. I have yet to obtain a copy of the above standard
228 * so this is a bit of a guess...
229 *
230 * A fair chunk of this is based on the Linux parport implementation
231 * of IEEE 1284.
232 *
233 * Return 0 if data available
234 * 1 if no data available
235 */
236
237 unsigned short base = tmp->base;
238 unsigned char a, mode;
239
240 switch (tmp->mode) {
241 case IMM_NIBBLE:
242 mode = 0x00;
243 break;
244 case IMM_PS2:
245 mode = 0x01;
246 break;
247 default:
248 return 0;
249 }
250
251 w_ctr(base, 0x04);
252 udelay(5);
253 w_dtr(base, mode);
254 udelay(100);
255 w_ctr(base, 0x06);
256 udelay(5);
257 a = (r_str(base) & 0x20) ? 0 : 1;
258 udelay(5);
259 w_ctr(base, 0x07);
260 udelay(5);
261 w_ctr(base, 0x06);
262
263 if (a) {
264 printk
265 ("IMM: IEEE1284 negotiate indicates no data available.\n");
266 imm_fail(dev: tmp, error_code: DID_ERROR);
267 }
268 return a;
269}
270
271/*
272 * Clear EPP timeout bit.
273 */
274static inline void epp_reset(unsigned short ppb)
275{
276 int i;
277
278 i = r_str(ppb);
279 w_str(ppb, i);
280 w_str(ppb, i & 0xfe);
281}
282
283/*
284 * Wait for empty ECP fifo (if we are in ECP fifo mode only)
285 */
286static inline void ecp_sync(imm_struct *dev)
287{
288 int i, ppb_hi = dev->base_hi;
289
290 if (ppb_hi == 0)
291 return;
292
293 if ((r_ecr(ppb_hi) & 0xe0) == 0x60) { /* mode 011 == ECP fifo mode */
294 for (i = 0; i < 100; i++) {
295 if (r_ecr(ppb_hi) & 0x01)
296 return;
297 udelay(5);
298 }
299 printk("imm: ECP sync failed as data still present in FIFO.\n");
300 }
301}
302
303static int imm_byte_out(unsigned short base, const char *buffer, int len)
304{
305 int i;
306
307 w_ctr(base, 0x4); /* apparently a sane mode */
308 for (i = len >> 1; i; i--) {
309 w_dtr(base, *buffer++);
310 w_ctr(base, 0x5); /* Drop STROBE low */
311 w_dtr(base, *buffer++);
312 w_ctr(base, 0x0); /* STROBE high + INIT low */
313 }
314 w_ctr(base, 0x4); /* apparently a sane mode */
315 return 1; /* All went well - we hope! */
316}
317
318static int imm_nibble_in(unsigned short base, char *buffer, int len)
319{
320 unsigned char l;
321 int i;
322
323 /*
324 * The following is based on documented timing signals
325 */
326 w_ctr(base, 0x4);
327 for (i = len; i; i--) {
328 w_ctr(base, 0x6);
329 l = (r_str(base) & 0xf0) >> 4;
330 w_ctr(base, 0x5);
331 *buffer++ = (r_str(base) & 0xf0) | l;
332 w_ctr(base, 0x4);
333 }
334 return 1; /* All went well - we hope! */
335}
336
337static int imm_byte_in(unsigned short base, char *buffer, int len)
338{
339 int i;
340
341 /*
342 * The following is based on documented timing signals
343 */
344 w_ctr(base, 0x4);
345 for (i = len; i; i--) {
346 w_ctr(base, 0x26);
347 *buffer++ = r_dtr(base);
348 w_ctr(base, 0x25);
349 }
350 return 1; /* All went well - we hope! */
351}
352
353static int imm_out(imm_struct *dev, char *buffer, int len)
354{
355 unsigned short ppb = dev->base;
356 int r = imm_wait(dev);
357
358 /*
359 * Make sure that:
360 * a) the SCSI bus is BUSY (device still listening)
361 * b) the device is listening
362 */
363 if ((r & 0x18) != 0x08) {
364 imm_fail(dev, error_code: DID_ERROR);
365 printk("IMM: returned SCSI status %2x\n", r);
366 return 0;
367 }
368 switch (dev->mode) {
369 case IMM_EPP_32:
370 case IMM_EPP_16:
371 case IMM_EPP_8:
372 epp_reset(ppb);
373 w_ctr(ppb, 0x4);
374 if (dev->mode == IMM_EPP_32 && !(((long) buffer | len) & 0x03))
375 outsl(port: ppb + 4, addr: buffer, count: len >> 2);
376 else if (dev->mode == IMM_EPP_16 && !(((long) buffer | len) & 0x01))
377 outsw(port: ppb + 4, addr: buffer, count: len >> 1);
378 else
379 outsb(port: ppb + 4, addr: buffer, count: len);
380 w_ctr(ppb, 0xc);
381 r = !(r_str(ppb) & 0x01);
382 w_ctr(ppb, 0xc);
383 ecp_sync(dev);
384 break;
385
386 case IMM_NIBBLE:
387 case IMM_PS2:
388 /* 8 bit output, with a loop */
389 r = imm_byte_out(base: ppb, buffer, len);
390 break;
391
392 default:
393 printk("IMM: bug in imm_out()\n");
394 r = 0;
395 }
396 return r;
397}
398
399static int imm_in(imm_struct *dev, char *buffer, int len)
400{
401 unsigned short ppb = dev->base;
402 int r = imm_wait(dev);
403
404 /*
405 * Make sure that:
406 * a) the SCSI bus is BUSY (device still listening)
407 * b) the device is sending data
408 */
409 if ((r & 0x18) != 0x18) {
410 imm_fail(dev, error_code: DID_ERROR);
411 return 0;
412 }
413 switch (dev->mode) {
414 case IMM_NIBBLE:
415 /* 4 bit input, with a loop */
416 r = imm_nibble_in(base: ppb, buffer, len);
417 w_ctr(ppb, 0xc);
418 break;
419
420 case IMM_PS2:
421 /* 8 bit input, with a loop */
422 r = imm_byte_in(base: ppb, buffer, len);
423 w_ctr(ppb, 0xc);
424 break;
425
426 case IMM_EPP_32:
427 case IMM_EPP_16:
428 case IMM_EPP_8:
429 epp_reset(ppb);
430 w_ctr(ppb, 0x24);
431 if (dev->mode == IMM_EPP_32 && !(((long) buffer | len) & 0x03))
432 insw(port: ppb + 4, addr: buffer, count: len >> 2);
433 else if (dev->mode == IMM_EPP_16 && !(((long) buffer | len) & 0x01))
434 insl(port: ppb + 4, addr: buffer, count: len >> 1);
435 else
436 insb(port: ppb + 4, addr: buffer, count: 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, b: 0xe0); /* Select device 0 in compatible mode */
526 imm_cpp(ppb, b: 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, b: 0x28); /* Select device 0 in EPP mode */
532 return imm_cpp(ppb, b: 0xe0); /* Select device 0 in compatible mode */
533}
534
535static void imm_disconnect(imm_struct *dev)
536{
537 imm_cpp(ppb: dev->base, b: 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 bool autodetect = dev->mode == IMM_AUTODETECT;
592
593 if (autodetect) {
594 int modes = dev->dev->port->modes;
595
596 /* Mode detection works up the chain of speed
597 * This avoids a nasty if-then-else-if-... tree
598 */
599 dev->mode = IMM_NIBBLE;
600
601 if (modes & PARPORT_MODE_TRISTATE)
602 dev->mode = IMM_PS2;
603 }
604
605 if (imm_connect(dev, flag: 0) != 1)
606 return -EIO;
607 imm_reset_pulse(base: dev->base);
608 mdelay(1); /* Delay to allow devices to settle */
609 imm_disconnect(dev);
610 mdelay(1); /* Another delay to allow devices to settle */
611
612 return device_check(dev, autodetect);
613}
614
615static inline int imm_send_command(struct scsi_cmnd *cmd)
616{
617 imm_struct *dev = imm_dev(host: cmd->device->host);
618 int k;
619
620 /* NOTE: IMM uses byte pairs */
621 for (k = 0; k < cmd->cmd_len; k += 2)
622 if (!imm_out(dev, buffer: &cmd->cmnd[k], len: 2))
623 return 0;
624 return 1;
625}
626
627/*
628 * The bulk flag enables some optimisations in the data transfer loops,
629 * it should be true for any command that transfers data in integral
630 * numbers of sectors.
631 *
632 * The driver appears to remain stable if we speed up the parallel port
633 * i/o in this function, but not elsewhere.
634 */
635static int imm_completion(struct scsi_cmnd *const cmd)
636{
637 /* Return codes:
638 * -1 Error
639 * 0 Told to schedule
640 * 1 Finished data transfer
641 */
642 struct scsi_pointer *scsi_pointer = imm_scsi_pointer(cmd);
643 imm_struct *dev = imm_dev(host: cmd->device->host);
644 unsigned short ppb = dev->base;
645 unsigned long start_jiffies = jiffies;
646
647 unsigned char r, v;
648 int fast, bulk, status;
649
650 v = cmd->cmnd[0];
651 bulk = ((v == READ_6) ||
652 (v == READ_10) || (v == WRITE_6) || (v == WRITE_10));
653
654 /*
655 * We only get here if the drive is ready to comunicate,
656 * hence no need for a full imm_wait.
657 */
658 w_ctr(ppb, 0x0c);
659 r = (r_str(ppb) & 0xb8);
660
661 /*
662 * while (device is not ready to send status byte)
663 * loop;
664 */
665 while (r != (unsigned char) 0xb8) {
666 /*
667 * If we have been running for more than a full timer tick
668 * then take a rest.
669 */
670 if (time_after(jiffies, start_jiffies + 1))
671 return 0;
672
673 /*
674 * FAIL if:
675 * a) Drive status is screwy (!ready && !present)
676 * b) Drive is requesting/sending more data than expected
677 */
678 if ((r & 0x88) != 0x88 || scsi_pointer->this_residual <= 0) {
679 imm_fail(dev, error_code: DID_ERROR);
680 return -1; /* ERROR_RETURN */
681 }
682 /* determine if we should use burst I/O */
683 if (dev->rd == 0) {
684 fast = bulk && scsi_pointer->this_residual >=
685 IMM_BURST_SIZE ? IMM_BURST_SIZE : 2;
686 status = imm_out(dev, buffer: scsi_pointer->ptr, len: fast);
687 } else {
688 fast = bulk && scsi_pointer->this_residual >=
689 IMM_BURST_SIZE ? IMM_BURST_SIZE : 1;
690 status = imm_in(dev, buffer: scsi_pointer->ptr, len: fast);
691 }
692
693 scsi_pointer->ptr += fast;
694 scsi_pointer->this_residual -= fast;
695
696 if (!status) {
697 imm_fail(dev, error_code: DID_BUS_BUSY);
698 return -1; /* ERROR_RETURN */
699 }
700 if (scsi_pointer->buffer && !scsi_pointer->this_residual) {
701 /* if scatter/gather, advance to the next segment */
702 if (scsi_pointer->buffers_residual--) {
703 scsi_pointer->buffer =
704 sg_next(scsi_pointer->buffer);
705 scsi_pointer->this_residual =
706 scsi_pointer->buffer->length;
707 scsi_pointer->ptr = sg_virt(sg: scsi_pointer->buffer);
708
709 /*
710 * Make sure that we transfer even number of bytes
711 * otherwise it makes imm_byte_out() messy.
712 */
713 if (scsi_pointer->this_residual & 0x01)
714 scsi_pointer->this_residual++;
715 }
716 }
717 /* Now check to see if the drive is ready to comunicate */
718 w_ctr(ppb, 0x0c);
719 r = (r_str(ppb) & 0xb8);
720
721 /* If not, drop back down to the scheduler and wait a timer tick */
722 if (!(r & 0x80))
723 return 0;
724 }
725 return 1; /* FINISH_RETURN */
726}
727
728/*
729 * Since the IMM itself doesn't generate interrupts, we use
730 * the scheduler's task queue to generate a stream of call-backs and
731 * complete the request when the drive is ready.
732 */
733static void imm_interrupt(struct work_struct *work)
734{
735 imm_struct *dev = container_of(work, imm_struct, imm_tq.work);
736 struct scsi_cmnd *cmd = dev->cur_cmd;
737 struct Scsi_Host *host = cmd->device->host;
738 unsigned long flags;
739
740 if (imm_engine(dev, cmd)) {
741 schedule_delayed_work(dwork: &dev->imm_tq, delay: 1);
742 return;
743 }
744 /* Command must of completed hence it is safe to let go... */
745#if IMM_DEBUG > 0
746 switch ((cmd->result >> 16) & 0xff) {
747 case DID_OK:
748 break;
749 case DID_NO_CONNECT:
750 printk("imm: no device at SCSI ID %i\n", cmd->device->id);
751 break;
752 case DID_BUS_BUSY:
753 printk("imm: BUS BUSY - EPP timeout detected\n");
754 break;
755 case DID_TIME_OUT:
756 printk("imm: unknown timeout\n");
757 break;
758 case DID_ABORT:
759 printk("imm: told to abort\n");
760 break;
761 case DID_PARITY:
762 printk("imm: parity error (???)\n");
763 break;
764 case DID_ERROR:
765 printk("imm: internal driver error\n");
766 break;
767 case DID_RESET:
768 printk("imm: told to reset device\n");
769 break;
770 case DID_BAD_INTR:
771 printk("imm: bad interrupt (???)\n");
772 break;
773 default:
774 printk("imm: bad return code (%02x)\n",
775 (cmd->result >> 16) & 0xff);
776 }
777#endif
778
779 if (imm_scsi_pointer(cmd)->phase > 1)
780 imm_disconnect(dev);
781
782 imm_pb_dismiss(dev);
783
784 spin_lock_irqsave(host->host_lock, flags);
785 dev->cur_cmd = NULL;
786 scsi_done(cmd);
787 spin_unlock_irqrestore(lock: host->host_lock, flags);
788 return;
789}
790
791static int imm_engine(imm_struct *dev, struct scsi_cmnd *const cmd)
792{
793 struct scsi_pointer *scsi_pointer = imm_scsi_pointer(cmd);
794 unsigned short ppb = dev->base;
795 unsigned char l = 0, h = 0;
796 int retv, x;
797
798 /* First check for any errors that may have occurred
799 * Here we check for internal errors
800 */
801 if (dev->failed)
802 return 0;
803
804 switch (scsi_pointer->phase) {
805 case 0: /* Phase 0 - Waiting for parport */
806 if (time_after(jiffies, dev->jstart + HZ)) {
807 /*
808 * We waited more than a second
809 * for parport to call us
810 */
811 imm_fail(dev, error_code: DID_BUS_BUSY);
812 return 0;
813 }
814 return 1; /* wait until imm_wakeup claims parport */
815
816 case 1: /* Phase 1 - Connected */
817 imm_connect(dev, CONNECT_EPP_MAYBE);
818 scsi_pointer->phase++;
819 fallthrough;
820
821 case 2: /* Phase 2 - We are now talking to the scsi bus */
822 if (!imm_select(dev, scmd_id(cmd))) {
823 imm_fail(dev, error_code: DID_NO_CONNECT);
824 return 0;
825 }
826 scsi_pointer->phase++;
827 fallthrough;
828
829 case 3: /* Phase 3 - Ready to accept a command */
830 w_ctr(ppb, 0x0c);
831 if (!(r_str(ppb) & 0x80))
832 return 1;
833
834 if (!imm_send_command(cmd))
835 return 0;
836 scsi_pointer->phase++;
837 fallthrough;
838
839 case 4: /* Phase 4 - Setup scatter/gather buffers */
840 if (scsi_bufflen(cmd)) {
841 scsi_pointer->buffer = scsi_sglist(cmd);
842 scsi_pointer->this_residual = scsi_pointer->buffer->length;
843 scsi_pointer->ptr = sg_virt(sg: scsi_pointer->buffer);
844 } else {
845 scsi_pointer->buffer = NULL;
846 scsi_pointer->this_residual = 0;
847 scsi_pointer->ptr = NULL;
848 }
849 scsi_pointer->buffers_residual = scsi_sg_count(cmd) - 1;
850 scsi_pointer->phase++;
851 if (scsi_pointer->this_residual & 0x01)
852 scsi_pointer->this_residual++;
853 fallthrough;
854
855 case 5: /* Phase 5 - Pre-Data transfer stage */
856 /* Spin lock for BUSY */
857 w_ctr(ppb, 0x0c);
858 if (!(r_str(ppb) & 0x80))
859 return 1;
860
861 /* Require negotiation for read requests */
862 x = (r_str(ppb) & 0xb8);
863 dev->rd = (x & 0x10) ? 1 : 0;
864 dev->dp = (x & 0x20) ? 0 : 1;
865
866 if ((dev->dp) && (dev->rd))
867 if (imm_negotiate(tmp: dev))
868 return 0;
869 scsi_pointer->phase++;
870 fallthrough;
871
872 case 6: /* Phase 6 - Data transfer stage */
873 /* Spin lock for BUSY */
874 w_ctr(ppb, 0x0c);
875 if (!(r_str(ppb) & 0x80))
876 return 1;
877
878 if (dev->dp) {
879 retv = imm_completion(cmd);
880 if (retv == -1)
881 return 0;
882 if (retv == 0)
883 return 1;
884 }
885 scsi_pointer->phase++;
886 fallthrough;
887
888 case 7: /* Phase 7 - Post data transfer stage */
889 if ((dev->dp) && (dev->rd)) {
890 if ((dev->mode == IMM_NIBBLE) || (dev->mode == IMM_PS2)) {
891 w_ctr(ppb, 0x4);
892 w_ctr(ppb, 0xc);
893 w_ctr(ppb, 0xe);
894 w_ctr(ppb, 0x4);
895 }
896 }
897 scsi_pointer->phase++;
898 fallthrough;
899
900 case 8: /* Phase 8 - Read status/message */
901 /* Check for data overrun */
902 if (imm_wait(dev) != (unsigned char) 0xb8) {
903 imm_fail(dev, error_code: DID_ERROR);
904 return 0;
905 }
906 if (imm_negotiate(tmp: dev))
907 return 0;
908 if (imm_in(dev, buffer: &l, len: 1)) { /* read status byte */
909 /* Check for optional message byte */
910 if (imm_wait(dev) == (unsigned char) 0xb8)
911 imm_in(dev, buffer: &h, len: 1);
912 cmd->result = (DID_OK << 16) | (l & STATUS_MASK);
913 }
914 if ((dev->mode == IMM_NIBBLE) || (dev->mode == IMM_PS2)) {
915 w_ctr(ppb, 0x4);
916 w_ctr(ppb, 0xc);
917 w_ctr(ppb, 0xe);
918 w_ctr(ppb, 0x4);
919 }
920 return 0; /* Finished */
921
922 default:
923 printk("imm: Invalid scsi phase\n");
924 }
925 return 0;
926}
927
928static int imm_queuecommand_lck(struct scsi_cmnd *cmd)
929{
930 imm_struct *dev = imm_dev(host: cmd->device->host);
931
932 if (dev->cur_cmd) {
933 printk("IMM: bug in imm_queuecommand\n");
934 return 0;
935 }
936 dev->failed = 0;
937 dev->jstart = jiffies;
938 dev->cur_cmd = cmd;
939 cmd->result = DID_ERROR << 16; /* default return code */
940 imm_scsi_pointer(cmd)->phase = 0; /* bus free */
941
942 schedule_delayed_work(dwork: &dev->imm_tq, delay: 0);
943
944 imm_pb_claim(dev);
945
946 return 0;
947}
948
949static DEF_SCSI_QCMD(imm_queuecommand)
950
951/*
952 * Apparently the disk->capacity attribute is off by 1 sector
953 * for all disk drives. We add the one here, but it should really
954 * be done in sd.c. Even if it gets fixed there, this will still
955 * work.
956 */
957static int imm_biosparam(struct scsi_device *sdev, struct block_device *dev,
958 sector_t capacity, int ip[])
959{
960 ip[0] = 0x40;
961 ip[1] = 0x20;
962 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]);
963 if (ip[2] > 1024) {
964 ip[0] = 0xff;
965 ip[1] = 0x3f;
966 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]);
967 }
968 return 0;
969}
970
971static int imm_abort(struct scsi_cmnd *cmd)
972{
973 imm_struct *dev = imm_dev(host: cmd->device->host);
974 /*
975 * There is no method for aborting commands since Iomega
976 * have tied the SCSI_MESSAGE line high in the interface
977 */
978
979 switch (imm_scsi_pointer(cmd)->phase) {
980 case 0: /* Do not have access to parport */
981 case 1: /* Have not connected to interface */
982 dev->cur_cmd = NULL; /* Forget the problem */
983 return SUCCESS;
984 default: /* SCSI command sent, can not abort */
985 return FAILED;
986 }
987}
988
989static void imm_reset_pulse(unsigned int base)
990{
991 w_ctr(base, 0x04);
992 w_dtr(base, 0x40);
993 udelay(1);
994 w_ctr(base, 0x0c);
995 w_ctr(base, 0x0d);
996 udelay(50);
997 w_ctr(base, 0x0c);
998 w_ctr(base, 0x04);
999}
1000
1001static int imm_reset(struct scsi_cmnd *cmd)
1002{
1003 imm_struct *dev = imm_dev(host: cmd->device->host);
1004
1005 if (imm_scsi_pointer(cmd)->phase)
1006 imm_disconnect(dev);
1007 dev->cur_cmd = NULL; /* Forget the problem */
1008
1009 imm_connect(dev, CONNECT_NORMAL);
1010 imm_reset_pulse(base: dev->base);
1011 mdelay(1); /* device settle delay */
1012 imm_disconnect(dev);
1013 mdelay(1); /* device settle delay */
1014 return SUCCESS;
1015}
1016
1017static int device_check(imm_struct *dev, bool autodetect)
1018{
1019 /* This routine looks for a device and then attempts to use EPP
1020 to send a command. If all goes as planned then EPP is available. */
1021
1022 static char cmd[6] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
1023 int loop, old_mode, status, k, ppb = dev->base;
1024 unsigned char l;
1025
1026 old_mode = dev->mode;
1027 for (loop = 0; loop < 8; loop++) {
1028 /* Attempt to use EPP for Test Unit Ready */
1029 if (autodetect && (ppb & 0x0007) == 0x0000)
1030 dev->mode = IMM_EPP_8;
1031
1032 second_pass:
1033 imm_connect(dev, CONNECT_EPP_MAYBE);
1034 /* Select SCSI device */
1035 if (!imm_select(dev, target: loop)) {
1036 imm_disconnect(dev);
1037 continue;
1038 }
1039 printk("imm: Found device at ID %i, Attempting to use %s\n",
1040 loop, IMM_MODE_STRING[dev->mode]);
1041
1042 /* Send SCSI command */
1043 status = 1;
1044 w_ctr(ppb, 0x0c);
1045 for (l = 0; (l < 3) && (status); l++)
1046 status = imm_out(dev, buffer: &cmd[l << 1], len: 2);
1047
1048 if (!status) {
1049 imm_disconnect(dev);
1050 imm_connect(dev, CONNECT_EPP_MAYBE);
1051 imm_reset_pulse(base: dev->base);
1052 udelay(1000);
1053 imm_disconnect(dev);
1054 udelay(1000);
1055 if (dev->mode != old_mode) {
1056 dev->mode = old_mode;
1057 goto second_pass;
1058 }
1059 printk("imm: Unable to establish communication\n");
1060 return -EIO;
1061 }
1062 w_ctr(ppb, 0x0c);
1063
1064 k = 1000000; /* 1 Second */
1065 do {
1066 l = r_str(ppb);
1067 k--;
1068 udelay(1);
1069 } while (!(l & 0x80) && (k));
1070
1071 l &= 0xb8;
1072
1073 if (l != 0xb8) {
1074 imm_disconnect(dev);
1075 imm_connect(dev, CONNECT_EPP_MAYBE);
1076 imm_reset_pulse(base: dev->base);
1077 udelay(1000);
1078 imm_disconnect(dev);
1079 udelay(1000);
1080 if (dev->mode != old_mode) {
1081 dev->mode = old_mode;
1082 goto second_pass;
1083 }
1084 printk
1085 ("imm: Unable to establish communication\n");
1086 return -EIO;
1087 }
1088 imm_disconnect(dev);
1089 printk
1090 ("imm: Communication established at 0x%x with ID %i using %s\n",
1091 ppb, loop, IMM_MODE_STRING[dev->mode]);
1092 imm_connect(dev, CONNECT_EPP_MAYBE);
1093 imm_reset_pulse(base: dev->base);
1094 udelay(1000);
1095 imm_disconnect(dev);
1096 udelay(1000);
1097 return 0;
1098 }
1099 printk("imm: No devices found\n");
1100 return -ENODEV;
1101}
1102
1103/*
1104 * imm cannot deal with highmem, so this causes all IO pages for this host
1105 * to reside in low memory (hence mapped)
1106 */
1107static int imm_adjust_queue(struct scsi_device *device)
1108{
1109 blk_queue_bounce_limit(q: device->request_queue, limit: BLK_BOUNCE_HIGH);
1110 return 0;
1111}
1112
1113static const struct scsi_host_template imm_template = {
1114 .module = THIS_MODULE,
1115 .proc_name = "imm",
1116 .show_info = imm_show_info,
1117 .write_info = imm_write_info,
1118 .name = "Iomega VPI2 (imm) interface",
1119 .queuecommand = imm_queuecommand,
1120 .eh_abort_handler = imm_abort,
1121 .eh_host_reset_handler = imm_reset,
1122 .bios_param = imm_biosparam,
1123 .this_id = 7,
1124 .sg_tablesize = SG_ALL,
1125 .can_queue = 1,
1126 .slave_alloc = imm_adjust_queue,
1127 .cmd_size = sizeof(struct scsi_pointer),
1128};
1129
1130/***************************************************************************
1131 * Parallel port probing routines *
1132 ***************************************************************************/
1133
1134static LIST_HEAD(imm_hosts);
1135
1136/*
1137 * Finds the first available device number that can be alloted to the
1138 * new imm device and returns the address of the previous node so that
1139 * we can add to the tail and have a list in the ascending order.
1140 */
1141
1142static inline imm_struct *find_parent(void)
1143{
1144 imm_struct *dev, *par = NULL;
1145 unsigned int cnt = 0;
1146
1147 if (list_empty(head: &imm_hosts))
1148 return NULL;
1149
1150 list_for_each_entry(dev, &imm_hosts, list) {
1151 if (dev->dev_no != cnt)
1152 return par;
1153 cnt++;
1154 par = dev;
1155 }
1156
1157 return par;
1158}
1159
1160static int __imm_attach(struct parport *pb)
1161{
1162 struct Scsi_Host *host;
1163 imm_struct *dev, *temp;
1164 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(waiting);
1165 DEFINE_WAIT(wait);
1166 int ports;
1167 int err = -ENOMEM;
1168 struct pardev_cb imm_cb;
1169
1170 init_waitqueue_head(&waiting);
1171
1172 dev = kzalloc(size: sizeof(imm_struct), GFP_KERNEL);
1173 if (!dev)
1174 return -ENOMEM;
1175
1176
1177 dev->base = -1;
1178 dev->mode = mode < IMM_UNKNOWN ? mode : IMM_AUTODETECT;
1179 INIT_LIST_HEAD(list: &dev->list);
1180
1181 temp = find_parent();
1182 if (temp)
1183 dev->dev_no = temp->dev_no + 1;
1184
1185 memset(&imm_cb, 0, sizeof(imm_cb));
1186 imm_cb.private = dev;
1187 imm_cb.wakeup = imm_wakeup;
1188
1189 dev->dev = parport_register_dev_model(port: pb, name: "imm", par_dev_cb: &imm_cb, cnt: dev->dev_no);
1190 if (!dev->dev)
1191 goto out;
1192
1193
1194 /* Claim the bus so it remembers what we do to the control
1195 * registers. [ CTR and ECP ]
1196 */
1197 err = -EBUSY;
1198 dev->waiting = &waiting;
1199 prepare_to_wait(wq_head: &waiting, wq_entry: &wait, TASK_UNINTERRUPTIBLE);
1200 if (imm_pb_claim(dev))
1201 schedule_timeout(timeout: 3 * HZ);
1202 if (dev->wanted) {
1203 printk(KERN_ERR "imm%d: failed to claim parport because "
1204 "a pardevice is owning the port for too long "
1205 "time!\n", pb->number);
1206 imm_pb_dismiss(dev);
1207 dev->waiting = NULL;
1208 finish_wait(wq_head: &waiting, wq_entry: &wait);
1209 goto out1;
1210 }
1211 dev->waiting = NULL;
1212 finish_wait(wq_head: &waiting, wq_entry: &wait);
1213 dev->base = dev->dev->port->base;
1214 dev->base_hi = dev->dev->port->base_hi;
1215 w_ctr(dev->base, 0x0c);
1216
1217 /* Done configuration */
1218
1219 err = imm_init(dev);
1220
1221 imm_pb_release(dev);
1222
1223 if (err)
1224 goto out1;
1225
1226 /* now the glue ... */
1227 if (dev->mode == IMM_NIBBLE || dev->mode == IMM_PS2)
1228 ports = 3;
1229 else
1230 ports = 8;
1231
1232 INIT_DELAYED_WORK(&dev->imm_tq, imm_interrupt);
1233
1234 err = -ENOMEM;
1235 host = scsi_host_alloc(&imm_template, sizeof(imm_struct *));
1236 if (!host)
1237 goto out1;
1238 host->io_port = pb->base;
1239 host->n_io_port = ports;
1240 host->dma_channel = -1;
1241 host->unique_id = pb->number;
1242 *(imm_struct **)&host->hostdata = dev;
1243 dev->host = host;
1244 if (!temp)
1245 list_add_tail(new: &dev->list, head: &imm_hosts);
1246 else
1247 list_add_tail(new: &dev->list, head: &temp->list);
1248 err = scsi_add_host(host, NULL);
1249 if (err)
1250 goto out2;
1251 scsi_scan_host(host);
1252 return 0;
1253
1254out2:
1255 list_del_init(entry: &dev->list);
1256 scsi_host_put(t: host);
1257out1:
1258 parport_unregister_device(dev: dev->dev);
1259out:
1260 kfree(objp: dev);
1261 return err;
1262}
1263
1264static void imm_attach(struct parport *pb)
1265{
1266 __imm_attach(pb);
1267}
1268
1269static void imm_detach(struct parport *pb)
1270{
1271 imm_struct *dev;
1272 list_for_each_entry(dev, &imm_hosts, list) {
1273 if (dev->dev->port == pb) {
1274 list_del_init(entry: &dev->list);
1275 scsi_remove_host(dev->host);
1276 scsi_host_put(t: dev->host);
1277 parport_unregister_device(dev: dev->dev);
1278 kfree(objp: dev);
1279 break;
1280 }
1281 }
1282}
1283
1284static struct parport_driver imm_driver = {
1285 .name = "imm",
1286 .match_port = imm_attach,
1287 .detach = imm_detach,
1288 .devmodel = true,
1289};
1290module_parport_driver(imm_driver);
1291
1292MODULE_LICENSE("GPL");
1293

source code of linux/drivers/scsi/imm.c