1/* ppa.c -- low level driver for the IOMEGA PPA3
2 * parallel port SCSI host adapter.
3 *
4 * (The PPA3 is the embedded controller in the ZIP drive.)
5 *
6 * (c) 1995,1996 Grant R. Guenther, grant@torque.net,
7 * under the terms of the GNU General Public License.
8 *
9 */
10
11#include <linux/init.h>
12#include <linux/kernel.h>
13#include <linux/slab.h>
14#include <linux/module.h>
15#include <linux/blkdev.h>
16#include <linux/parport.h>
17#include <linux/workqueue.h>
18#include <linux/delay.h>
19#include <linux/jiffies.h>
20#include <asm/io.h>
21
22#include <scsi/scsi.h>
23#include <scsi/scsi_cmnd.h>
24#include <scsi/scsi_device.h>
25#include <scsi/scsi_host.h>
26
27
28static void ppa_reset_pulse(unsigned int base);
29
30typedef struct {
31 struct pardevice *dev; /* Parport device entry */
32 int base; /* Actual port address */
33 int mode; /* Transfer mode */
34 struct scsi_cmnd *cur_cmd; /* Current queued command */
35 struct delayed_work ppa_tq; /* Polling interrupt stuff */
36 unsigned long jstart; /* Jiffies at start */
37 unsigned long recon_tmo; /* How many usecs to wait for reconnection (6th bit) */
38 unsigned int failed:1; /* Failure flag */
39 unsigned wanted:1; /* Parport sharing busy flag */
40 unsigned int dev_no; /* Device number */
41 wait_queue_head_t *waiting;
42 struct Scsi_Host *host;
43 struct list_head list;
44} ppa_struct;
45
46#include "ppa.h"
47
48static inline ppa_struct *ppa_dev(struct Scsi_Host *host)
49{
50 return *(ppa_struct **)&host->hostdata;
51}
52
53static DEFINE_SPINLOCK(arbitration_lock);
54
55static void got_it(ppa_struct *dev)
56{
57 dev->base = dev->dev->port->base;
58 if (dev->cur_cmd)
59 dev->cur_cmd->SCp.phase = 1;
60 else
61 wake_up(dev->waiting);
62}
63
64static void ppa_wakeup(void *ref)
65{
66 ppa_struct *dev = (ppa_struct *) ref;
67 unsigned long flags;
68
69 spin_lock_irqsave(&arbitration_lock, flags);
70 if (dev->wanted) {
71 parport_claim(dev->dev);
72 got_it(dev);
73 dev->wanted = 0;
74 }
75 spin_unlock_irqrestore(&arbitration_lock, flags);
76 return;
77}
78
79static int ppa_pb_claim(ppa_struct *dev)
80{
81 unsigned long flags;
82 int res = 1;
83 spin_lock_irqsave(&arbitration_lock, flags);
84 if (parport_claim(dev->dev) == 0) {
85 got_it(dev);
86 res = 0;
87 }
88 dev->wanted = res;
89 spin_unlock_irqrestore(&arbitration_lock, flags);
90 return res;
91}
92
93static void ppa_pb_dismiss(ppa_struct *dev)
94{
95 unsigned long flags;
96 int wanted;
97 spin_lock_irqsave(&arbitration_lock, flags);
98 wanted = dev->wanted;
99 dev->wanted = 0;
100 spin_unlock_irqrestore(&arbitration_lock, flags);
101 if (!wanted)
102 parport_release(dev->dev);
103}
104
105static inline void ppa_pb_release(ppa_struct *dev)
106{
107 parport_release(dev->dev);
108}
109
110/*
111 * Start of Chipset kludges
112 */
113
114/* This is to give the ppa driver a way to modify the timings (and other
115 * parameters) by writing to the /proc/scsi/ppa/0 file.
116 * Very simple method really... (To simple, no error checking :( )
117 * Reason: Kernel hackers HATE having to unload and reload modules for
118 * testing...
119 * Also gives a method to use a script to obtain optimum timings (TODO)
120 */
121
122static inline int ppa_write_info(struct Scsi_Host *host, char *buffer, int length)
123{
124 ppa_struct *dev = ppa_dev(host);
125 unsigned long x;
126
127 if ((length > 5) && (strncmp(buffer, "mode=", 5) == 0)) {
128 x = simple_strtoul(buffer + 5, NULL, 0);
129 dev->mode = x;
130 return length;
131 }
132 if ((length > 10) && (strncmp(buffer, "recon_tmo=", 10) == 0)) {
133 x = simple_strtoul(buffer + 10, NULL, 0);
134 dev->recon_tmo = x;
135 printk(KERN_INFO "ppa: recon_tmo set to %ld\n", x);
136 return length;
137 }
138 printk(KERN_WARNING "ppa /proc: invalid variable\n");
139 return -EINVAL;
140}
141
142static int ppa_show_info(struct seq_file *m, struct Scsi_Host *host)
143{
144 ppa_struct *dev = ppa_dev(host);
145
146 seq_printf(m, "Version : %s\n", PPA_VERSION);
147 seq_printf(m, "Parport : %s\n", dev->dev->port->name);
148 seq_printf(m, "Mode : %s\n", PPA_MODE_STRING[dev->mode]);
149#if PPA_DEBUG > 0
150 seq_printf(m, "recon_tmo : %lu\n", dev->recon_tmo);
151#endif
152 return 0;
153}
154
155static int device_check(ppa_struct *dev);
156
157#if PPA_DEBUG > 0
158#define ppa_fail(x,y) printk("ppa: ppa_fail(%i) from %s at line %d\n",\
159 y, __func__, __LINE__); ppa_fail_func(x,y);
160static inline void ppa_fail_func(ppa_struct *dev, int error_code)
161#else
162static inline void ppa_fail(ppa_struct *dev, int error_code)
163#endif
164{
165 /* If we fail a device then we trash status / message bytes */
166 if (dev->cur_cmd) {
167 dev->cur_cmd->result = error_code << 16;
168 dev->failed = 1;
169 }
170}
171
172/*
173 * Wait for the high bit to be set.
174 *
175 * In principle, this could be tied to an interrupt, but the adapter
176 * doesn't appear to be designed to support interrupts. We spin on
177 * the 0x80 ready bit.
178 */
179static unsigned char ppa_wait(ppa_struct *dev)
180{
181 int k;
182 unsigned short ppb = dev->base;
183 unsigned char r;
184
185 k = PPA_SPIN_TMO;
186 /* Wait for bit 6 and 7 - PJC */
187 for (r = r_str(ppb); ((r & 0xc0) != 0xc0) && (k); k--) {
188 udelay(1);
189 r = r_str(ppb);
190 }
191
192 /*
193 * return some status information.
194 * Semantics: 0xc0 = ZIP wants more data
195 * 0xd0 = ZIP wants to send more data
196 * 0xe0 = ZIP is expecting SCSI command data
197 * 0xf0 = end of transfer, ZIP is sending status
198 */
199 if (k)
200 return (r & 0xf0);
201
202 /* Counter expired - Time out occurred */
203 ppa_fail(dev, DID_TIME_OUT);
204 printk(KERN_WARNING "ppa timeout in ppa_wait\n");
205 return 0; /* command timed out */
206}
207
208/*
209 * Clear EPP Timeout Bit
210 */
211static inline void epp_reset(unsigned short ppb)
212{
213 int i;
214
215 i = r_str(ppb);
216 w_str(ppb, i);
217 w_str(ppb, i & 0xfe);
218}
219
220/*
221 * Wait for empty ECP fifo (if we are in ECP fifo mode only)
222 */
223static inline void ecp_sync(ppa_struct *dev)
224{
225 int i, ppb_hi = dev->dev->port->base_hi;
226
227 if (ppb_hi == 0)
228 return;
229
230 if ((r_ecr(ppb_hi) & 0xe0) == 0x60) { /* mode 011 == ECP fifo mode */
231 for (i = 0; i < 100; i++) {
232 if (r_ecr(ppb_hi) & 0x01)
233 return;
234 udelay(5);
235 }
236 printk(KERN_WARNING "ppa: ECP sync failed as data still present in FIFO.\n");
237 }
238}
239
240static int ppa_byte_out(unsigned short base, const char *buffer, int len)
241{
242 int i;
243
244 for (i = len; i; i--) {
245 w_dtr(base, *buffer++);
246 w_ctr(base, 0xe);
247 w_ctr(base, 0xc);
248 }
249 return 1; /* All went well - we hope! */
250}
251
252static int ppa_byte_in(unsigned short base, char *buffer, int len)
253{
254 int i;
255
256 for (i = len; i; i--) {
257 *buffer++ = r_dtr(base);
258 w_ctr(base, 0x27);
259 w_ctr(base, 0x25);
260 }
261 return 1; /* All went well - we hope! */
262}
263
264static int ppa_nibble_in(unsigned short base, char *buffer, int len)
265{
266 for (; len; len--) {
267 unsigned char h;
268
269 w_ctr(base, 0x4);
270 h = r_str(base) & 0xf0;
271 w_ctr(base, 0x6);
272 *buffer++ = h | ((r_str(base) & 0xf0) >> 4);
273 }
274 return 1; /* All went well - we hope! */
275}
276
277static int ppa_out(ppa_struct *dev, char *buffer, int len)
278{
279 int r;
280 unsigned short ppb = dev->base;
281
282 r = ppa_wait(dev);
283
284 if ((r & 0x50) != 0x40) {
285 ppa_fail(dev, DID_ERROR);
286 return 0;
287 }
288 switch (dev->mode) {
289 case PPA_NIBBLE:
290 case PPA_PS2:
291 /* 8 bit output, with a loop */
292 r = ppa_byte_out(ppb, buffer, len);
293 break;
294
295 case PPA_EPP_32:
296 case PPA_EPP_16:
297 case PPA_EPP_8:
298 epp_reset(ppb);
299 w_ctr(ppb, 0x4);
300#ifdef CONFIG_SCSI_IZIP_EPP16
301 if (!(((long) buffer | len) & 0x01))
302 outsw(ppb + 4, buffer, len >> 1);
303#else
304 if (!(((long) buffer | len) & 0x03))
305 outsl(ppb + 4, buffer, len >> 2);
306#endif
307 else
308 outsb(ppb + 4, buffer, len);
309 w_ctr(ppb, 0xc);
310 r = !(r_str(ppb) & 0x01);
311 w_ctr(ppb, 0xc);
312 ecp_sync(dev);
313 break;
314
315 default:
316 printk(KERN_ERR "PPA: bug in ppa_out()\n");
317 r = 0;
318 }
319 return r;
320}
321
322static int ppa_in(ppa_struct *dev, char *buffer, int len)
323{
324 int r;
325 unsigned short ppb = dev->base;
326
327 r = ppa_wait(dev);
328
329 if ((r & 0x50) != 0x50) {
330 ppa_fail(dev, DID_ERROR);
331 return 0;
332 }
333 switch (dev->mode) {
334 case PPA_NIBBLE:
335 /* 4 bit input, with a loop */
336 r = ppa_nibble_in(ppb, buffer, len);
337 w_ctr(ppb, 0xc);
338 break;
339
340 case PPA_PS2:
341 /* 8 bit input, with a loop */
342 w_ctr(ppb, 0x25);
343 r = ppa_byte_in(ppb, buffer, len);
344 w_ctr(ppb, 0x4);
345 w_ctr(ppb, 0xc);
346 break;
347
348 case PPA_EPP_32:
349 case PPA_EPP_16:
350 case PPA_EPP_8:
351 epp_reset(ppb);
352 w_ctr(ppb, 0x24);
353#ifdef CONFIG_SCSI_IZIP_EPP16
354 if (!(((long) buffer | len) & 0x01))
355 insw(ppb + 4, buffer, len >> 1);
356#else
357 if (!(((long) buffer | len) & 0x03))
358 insl(ppb + 4, buffer, len >> 2);
359#endif
360 else
361 insb(ppb + 4, buffer, len);
362 w_ctr(ppb, 0x2c);
363 r = !(r_str(ppb) & 0x01);
364 w_ctr(ppb, 0x2c);
365 ecp_sync(dev);
366 break;
367
368 default:
369 printk(KERN_ERR "PPA: bug in ppa_ins()\n");
370 r = 0;
371 break;
372 }
373 return r;
374}
375
376/* end of ppa_io.h */
377static inline void ppa_d_pulse(unsigned short ppb, unsigned char b)
378{
379 w_dtr(ppb, b);
380 w_ctr(ppb, 0xc);
381 w_ctr(ppb, 0xe);
382 w_ctr(ppb, 0xc);
383 w_ctr(ppb, 0x4);
384 w_ctr(ppb, 0xc);
385}
386
387static void ppa_disconnect(ppa_struct *dev)
388{
389 unsigned short ppb = dev->base;
390
391 ppa_d_pulse(ppb, 0);
392 ppa_d_pulse(ppb, 0x3c);
393 ppa_d_pulse(ppb, 0x20);
394 ppa_d_pulse(ppb, 0xf);
395}
396
397static inline void ppa_c_pulse(unsigned short ppb, unsigned char b)
398{
399 w_dtr(ppb, b);
400 w_ctr(ppb, 0x4);
401 w_ctr(ppb, 0x6);
402 w_ctr(ppb, 0x4);
403 w_ctr(ppb, 0xc);
404}
405
406static inline void ppa_connect(ppa_struct *dev, int flag)
407{
408 unsigned short ppb = dev->base;
409
410 ppa_c_pulse(ppb, 0);
411 ppa_c_pulse(ppb, 0x3c);
412 ppa_c_pulse(ppb, 0x20);
413 if ((flag == CONNECT_EPP_MAYBE) && IN_EPP_MODE(dev->mode))
414 ppa_c_pulse(ppb, 0xcf);
415 else
416 ppa_c_pulse(ppb, 0x8f);
417}
418
419static int ppa_select(ppa_struct *dev, int target)
420{
421 int k;
422 unsigned short ppb = dev->base;
423
424 /*
425 * Bit 6 (0x40) is the device selected bit.
426 * First we must wait till the current device goes off line...
427 */
428 k = PPA_SELECT_TMO;
429 do {
430 k--;
431 udelay(1);
432 } while ((r_str(ppb) & 0x40) && (k));
433 if (!k)
434 return 0;
435
436 w_dtr(ppb, (1 << target));
437 w_ctr(ppb, 0xe);
438 w_ctr(ppb, 0xc);
439 w_dtr(ppb, 0x80); /* This is NOT the initator */
440 w_ctr(ppb, 0x8);
441
442 k = PPA_SELECT_TMO;
443 do {
444 k--;
445 udelay(1);
446 }
447 while (!(r_str(ppb) & 0x40) && (k));
448 if (!k)
449 return 0;
450
451 return 1;
452}
453
454/*
455 * This is based on a trace of what the Iomega DOS 'guest' driver does.
456 * I've tried several different kinds of parallel ports with guest and
457 * coded this to react in the same ways that it does.
458 *
459 * The return value from this function is just a hint about where the
460 * handshaking failed.
461 *
462 */
463static int ppa_init(ppa_struct *dev)
464{
465 int retv;
466 unsigned short ppb = dev->base;
467
468 ppa_disconnect(dev);
469 ppa_connect(dev, CONNECT_NORMAL);
470
471 retv = 2; /* Failed */
472
473 w_ctr(ppb, 0xe);
474 if ((r_str(ppb) & 0x08) == 0x08)
475 retv--;
476
477 w_ctr(ppb, 0xc);
478 if ((r_str(ppb) & 0x08) == 0x00)
479 retv--;
480
481 if (!retv)
482 ppa_reset_pulse(ppb);
483 udelay(1000); /* Allow devices to settle down */
484 ppa_disconnect(dev);
485 udelay(1000); /* Another delay to allow devices to settle */
486
487 if (retv)
488 return -EIO;
489
490 return device_check(dev);
491}
492
493static inline int ppa_send_command(struct scsi_cmnd *cmd)
494{
495 ppa_struct *dev = ppa_dev(cmd->device->host);
496 int k;
497
498 w_ctr(dev->base, 0x0c);
499
500 for (k = 0; k < cmd->cmd_len; k++)
501 if (!ppa_out(dev, &cmd->cmnd[k], 1))
502 return 0;
503 return 1;
504}
505
506/*
507 * The bulk flag enables some optimisations in the data transfer loops,
508 * it should be true for any command that transfers data in integral
509 * numbers of sectors.
510 *
511 * The driver appears to remain stable if we speed up the parallel port
512 * i/o in this function, but not elsewhere.
513 */
514static int ppa_completion(struct scsi_cmnd *cmd)
515{
516 /* Return codes:
517 * -1 Error
518 * 0 Told to schedule
519 * 1 Finished data transfer
520 */
521 ppa_struct *dev = ppa_dev(cmd->device->host);
522 unsigned short ppb = dev->base;
523 unsigned long start_jiffies = jiffies;
524
525 unsigned char r, v;
526 int fast, bulk, status;
527
528 v = cmd->cmnd[0];
529 bulk = ((v == READ_6) ||
530 (v == READ_10) || (v == WRITE_6) || (v == WRITE_10));
531
532 /*
533 * We only get here if the drive is ready to comunicate,
534 * hence no need for a full ppa_wait.
535 */
536 r = (r_str(ppb) & 0xf0);
537
538 while (r != (unsigned char) 0xf0) {
539 /*
540 * If we have been running for more than a full timer tick
541 * then take a rest.
542 */
543 if (time_after(jiffies, start_jiffies + 1))
544 return 0;
545
546 if ((cmd->SCp.this_residual <= 0)) {
547 ppa_fail(dev, DID_ERROR);
548 return -1; /* ERROR_RETURN */
549 }
550
551 /* On some hardware we have SCSI disconnected (6th bit low)
552 * for about 100usecs. It is too expensive to wait a
553 * tick on every loop so we busy wait for no more than
554 * 500usecs to give the drive a chance first. We do not
555 * change things for "normal" hardware since generally
556 * the 6th bit is always high.
557 * This makes the CPU load higher on some hardware
558 * but otherwise we can not get more than 50K/secs
559 * on this problem hardware.
560 */
561 if ((r & 0xc0) != 0xc0) {
562 /* Wait for reconnection should be no more than
563 * jiffy/2 = 5ms = 5000 loops
564 */
565 unsigned long k = dev->recon_tmo;
566 for (; k && ((r = (r_str(ppb) & 0xf0)) & 0xc0) != 0xc0;
567 k--)
568 udelay(1);
569
570 if (!k)
571 return 0;
572 }
573
574 /* determine if we should use burst I/O */
575 fast = (bulk && (cmd->SCp.this_residual >= PPA_BURST_SIZE))
576 ? PPA_BURST_SIZE : 1;
577
578 if (r == (unsigned char) 0xc0)
579 status = ppa_out(dev, cmd->SCp.ptr, fast);
580 else
581 status = ppa_in(dev, cmd->SCp.ptr, fast);
582
583 cmd->SCp.ptr += fast;
584 cmd->SCp.this_residual -= fast;
585
586 if (!status) {
587 ppa_fail(dev, DID_BUS_BUSY);
588 return -1; /* ERROR_RETURN */
589 }
590 if (cmd->SCp.buffer && !cmd->SCp.this_residual) {
591 /* if scatter/gather, advance to the next segment */
592 if (cmd->SCp.buffers_residual--) {
593 cmd->SCp.buffer++;
594 cmd->SCp.this_residual =
595 cmd->SCp.buffer->length;
596 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
597 }
598 }
599 /* Now check to see if the drive is ready to comunicate */
600 r = (r_str(ppb) & 0xf0);
601 /* If not, drop back down to the scheduler and wait a timer tick */
602 if (!(r & 0x80))
603 return 0;
604 }
605 return 1; /* FINISH_RETURN */
606}
607
608/*
609 * Since the PPA itself doesn't generate interrupts, we use
610 * the scheduler's task queue to generate a stream of call-backs and
611 * complete the request when the drive is ready.
612 */
613static void ppa_interrupt(struct work_struct *work)
614{
615 ppa_struct *dev = container_of(work, ppa_struct, ppa_tq.work);
616 struct scsi_cmnd *cmd = dev->cur_cmd;
617
618 if (!cmd) {
619 printk(KERN_ERR "PPA: bug in ppa_interrupt\n");
620 return;
621 }
622 if (ppa_engine(dev, cmd)) {
623 schedule_delayed_work(&dev->ppa_tq, 1);
624 return;
625 }
626 /* Command must of completed hence it is safe to let go... */
627#if PPA_DEBUG > 0
628 switch ((cmd->result >> 16) & 0xff) {
629 case DID_OK:
630 break;
631 case DID_NO_CONNECT:
632 printk(KERN_DEBUG "ppa: no device at SCSI ID %i\n", cmd->device->target);
633 break;
634 case DID_BUS_BUSY:
635 printk(KERN_DEBUG "ppa: BUS BUSY - EPP timeout detected\n");
636 break;
637 case DID_TIME_OUT:
638 printk(KERN_DEBUG "ppa: unknown timeout\n");
639 break;
640 case DID_ABORT:
641 printk(KERN_DEBUG "ppa: told to abort\n");
642 break;
643 case DID_PARITY:
644 printk(KERN_DEBUG "ppa: parity error (???)\n");
645 break;
646 case DID_ERROR:
647 printk(KERN_DEBUG "ppa: internal driver error\n");
648 break;
649 case DID_RESET:
650 printk(KERN_DEBUG "ppa: told to reset device\n");
651 break;
652 case DID_BAD_INTR:
653 printk(KERN_WARNING "ppa: bad interrupt (???)\n");
654 break;
655 default:
656 printk(KERN_WARNING "ppa: bad return code (%02x)\n",
657 (cmd->result >> 16) & 0xff);
658 }
659#endif
660
661 if (cmd->SCp.phase > 1)
662 ppa_disconnect(dev);
663
664 ppa_pb_dismiss(dev);
665
666 dev->cur_cmd = NULL;
667
668 cmd->scsi_done(cmd);
669}
670
671static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd)
672{
673 unsigned short ppb = dev->base;
674 unsigned char l = 0, h = 0;
675 int retv;
676
677 /* First check for any errors that may of occurred
678 * Here we check for internal errors
679 */
680 if (dev->failed)
681 return 0;
682
683 switch (cmd->SCp.phase) {
684 case 0: /* Phase 0 - Waiting for parport */
685 if (time_after(jiffies, dev->jstart + HZ)) {
686 /*
687 * We waited more than a second
688 * for parport to call us
689 */
690 ppa_fail(dev, DID_BUS_BUSY);
691 return 0;
692 }
693 return 1; /* wait until ppa_wakeup claims parport */
694 case 1: /* Phase 1 - Connected */
695 { /* Perform a sanity check for cable unplugged */
696 int retv = 2; /* Failed */
697
698 ppa_connect(dev, CONNECT_EPP_MAYBE);
699
700 w_ctr(ppb, 0xe);
701 if ((r_str(ppb) & 0x08) == 0x08)
702 retv--;
703
704 w_ctr(ppb, 0xc);
705 if ((r_str(ppb) & 0x08) == 0x00)
706 retv--;
707
708 if (retv) {
709 if (time_after(jiffies, dev->jstart + (1 * HZ))) {
710 printk(KERN_ERR "ppa: Parallel port cable is unplugged.\n");
711 ppa_fail(dev, DID_BUS_BUSY);
712 return 0;
713 } else {
714 ppa_disconnect(dev);
715 return 1; /* Try again in a jiffy */
716 }
717 }
718 cmd->SCp.phase++;
719 }
720
721 case 2: /* Phase 2 - We are now talking to the scsi bus */
722 if (!ppa_select(dev, scmd_id(cmd))) {
723 ppa_fail(dev, DID_NO_CONNECT);
724 return 0;
725 }
726 cmd->SCp.phase++;
727 /* fall through */
728
729 case 3: /* Phase 3 - Ready to accept a command */
730 w_ctr(ppb, 0x0c);
731 if (!(r_str(ppb) & 0x80))
732 return 1;
733
734 if (!ppa_send_command(cmd))
735 return 0;
736 cmd->SCp.phase++;
737 /* fall through */
738
739 case 4: /* Phase 4 - Setup scatter/gather buffers */
740 if (scsi_bufflen(cmd)) {
741 cmd->SCp.buffer = scsi_sglist(cmd);
742 cmd->SCp.this_residual = cmd->SCp.buffer->length;
743 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
744 } else {
745 cmd->SCp.buffer = NULL;
746 cmd->SCp.this_residual = 0;
747 cmd->SCp.ptr = NULL;
748 }
749 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
750 cmd->SCp.phase++;
751 /* fall through */
752
753 case 5: /* Phase 5 - Data transfer stage */
754 w_ctr(ppb, 0x0c);
755 if (!(r_str(ppb) & 0x80))
756 return 1;
757
758 retv = ppa_completion(cmd);
759 if (retv == -1)
760 return 0;
761 if (retv == 0)
762 return 1;
763 cmd->SCp.phase++;
764 /* fall through */
765
766 case 6: /* Phase 6 - Read status/message */
767 cmd->result = DID_OK << 16;
768 /* Check for data overrun */
769 if (ppa_wait(dev) != (unsigned char) 0xf0) {
770 ppa_fail(dev, DID_ERROR);
771 return 0;
772 }
773 if (ppa_in(dev, &l, 1)) { /* read status byte */
774 /* Check for optional message byte */
775 if (ppa_wait(dev) == (unsigned char) 0xf0)
776 ppa_in(dev, &h, 1);
777 cmd->result =
778 (DID_OK << 16) + (h << 8) + (l & STATUS_MASK);
779 }
780 return 0; /* Finished */
781 break;
782
783 default:
784 printk(KERN_ERR "ppa: Invalid scsi phase\n");
785 }
786 return 0;
787}
788
789static int ppa_queuecommand_lck(struct scsi_cmnd *cmd,
790 void (*done) (struct scsi_cmnd *))
791{
792 ppa_struct *dev = ppa_dev(cmd->device->host);
793
794 if (dev->cur_cmd) {
795 printk(KERN_ERR "PPA: bug in ppa_queuecommand\n");
796 return 0;
797 }
798 dev->failed = 0;
799 dev->jstart = jiffies;
800 dev->cur_cmd = cmd;
801 cmd->scsi_done = done;
802 cmd->result = DID_ERROR << 16; /* default return code */
803 cmd->SCp.phase = 0; /* bus free */
804
805 schedule_delayed_work(&dev->ppa_tq, 0);
806
807 ppa_pb_claim(dev);
808
809 return 0;
810}
811
812static DEF_SCSI_QCMD(ppa_queuecommand)
813
814/*
815 * Apparently the disk->capacity attribute is off by 1 sector
816 * for all disk drives. We add the one here, but it should really
817 * be done in sd.c. Even if it gets fixed there, this will still
818 * work.
819 */
820static int ppa_biosparam(struct scsi_device *sdev, struct block_device *dev,
821 sector_t capacity, int ip[])
822{
823 ip[0] = 0x40;
824 ip[1] = 0x20;
825 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]);
826 if (ip[2] > 1024) {
827 ip[0] = 0xff;
828 ip[1] = 0x3f;
829 ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]);
830 if (ip[2] > 1023)
831 ip[2] = 1023;
832 }
833 return 0;
834}
835
836static int ppa_abort(struct scsi_cmnd *cmd)
837{
838 ppa_struct *dev = ppa_dev(cmd->device->host);
839 /*
840 * There is no method for aborting commands since Iomega
841 * have tied the SCSI_MESSAGE line high in the interface
842 */
843
844 switch (cmd->SCp.phase) {
845 case 0: /* Do not have access to parport */
846 case 1: /* Have not connected to interface */
847 dev->cur_cmd = NULL; /* Forget the problem */
848 return SUCCESS;
849 break;
850 default: /* SCSI command sent, can not abort */
851 return FAILED;
852 break;
853 }
854}
855
856static void ppa_reset_pulse(unsigned int base)
857{
858 w_dtr(base, 0x40);
859 w_ctr(base, 0x8);
860 udelay(30);
861 w_ctr(base, 0xc);
862}
863
864static int ppa_reset(struct scsi_cmnd *cmd)
865{
866 ppa_struct *dev = ppa_dev(cmd->device->host);
867
868 if (cmd->SCp.phase)
869 ppa_disconnect(dev);
870 dev->cur_cmd = NULL; /* Forget the problem */
871
872 ppa_connect(dev, CONNECT_NORMAL);
873 ppa_reset_pulse(dev->base);
874 mdelay(1); /* device settle delay */
875 ppa_disconnect(dev);
876 mdelay(1); /* device settle delay */
877 return SUCCESS;
878}
879
880static int device_check(ppa_struct *dev)
881{
882 /* This routine looks for a device and then attempts to use EPP
883 to send a command. If all goes as planned then EPP is available. */
884
885 static u8 cmd[6] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
886 int loop, old_mode, status, k, ppb = dev->base;
887 unsigned char l;
888
889 old_mode = dev->mode;
890 for (loop = 0; loop < 8; loop++) {
891 /* Attempt to use EPP for Test Unit Ready */
892 if ((ppb & 0x0007) == 0x0000)
893 dev->mode = PPA_EPP_32;
894
895second_pass:
896 ppa_connect(dev, CONNECT_EPP_MAYBE);
897 /* Select SCSI device */
898 if (!ppa_select(dev, loop)) {
899 ppa_disconnect(dev);
900 continue;
901 }
902 printk(KERN_INFO "ppa: Found device at ID %i, Attempting to use %s\n",
903 loop, PPA_MODE_STRING[dev->mode]);
904
905 /* Send SCSI command */
906 status = 1;
907 w_ctr(ppb, 0x0c);
908 for (l = 0; (l < 6) && (status); l++)
909 status = ppa_out(dev, cmd, 1);
910
911 if (!status) {
912 ppa_disconnect(dev);
913 ppa_connect(dev, CONNECT_EPP_MAYBE);
914 w_dtr(ppb, 0x40);
915 w_ctr(ppb, 0x08);
916 udelay(30);
917 w_ctr(ppb, 0x0c);
918 udelay(1000);
919 ppa_disconnect(dev);
920 udelay(1000);
921 if (dev->mode == PPA_EPP_32) {
922 dev->mode = old_mode;
923 goto second_pass;
924 }
925 return -EIO;
926 }
927 w_ctr(ppb, 0x0c);
928 k = 1000000; /* 1 Second */
929 do {
930 l = r_str(ppb);
931 k--;
932 udelay(1);
933 } while (!(l & 0x80) && (k));
934
935 l &= 0xf0;
936
937 if (l != 0xf0) {
938 ppa_disconnect(dev);
939 ppa_connect(dev, CONNECT_EPP_MAYBE);
940 ppa_reset_pulse(ppb);
941 udelay(1000);
942 ppa_disconnect(dev);
943 udelay(1000);
944 if (dev->mode == PPA_EPP_32) {
945 dev->mode = old_mode;
946 goto second_pass;
947 }
948 return -EIO;
949 }
950 ppa_disconnect(dev);
951 printk(KERN_INFO "ppa: Communication established with ID %i using %s\n",
952 loop, PPA_MODE_STRING[dev->mode]);
953 ppa_connect(dev, CONNECT_EPP_MAYBE);
954 ppa_reset_pulse(ppb);
955 udelay(1000);
956 ppa_disconnect(dev);
957 udelay(1000);
958 return 0;
959 }
960 return -ENODEV;
961}
962
963static int ppa_adjust_queue(struct scsi_device *device)
964{
965 blk_queue_bounce_limit(device->request_queue, BLK_BOUNCE_HIGH);
966 return 0;
967}
968
969static struct scsi_host_template ppa_template = {
970 .module = THIS_MODULE,
971 .proc_name = "ppa",
972 .show_info = ppa_show_info,
973 .write_info = ppa_write_info,
974 .name = "Iomega VPI0 (ppa) interface",
975 .queuecommand = ppa_queuecommand,
976 .eh_abort_handler = ppa_abort,
977 .eh_host_reset_handler = ppa_reset,
978 .bios_param = ppa_biosparam,
979 .this_id = -1,
980 .sg_tablesize = SG_ALL,
981 .can_queue = 1,
982 .slave_alloc = ppa_adjust_queue,
983};
984
985/***************************************************************************
986 * Parallel port probing routines *
987 ***************************************************************************/
988
989static LIST_HEAD(ppa_hosts);
990
991/*
992 * Finds the first available device number that can be alloted to the
993 * new ppa device and returns the address of the previous node so that
994 * we can add to the tail and have a list in the ascending order.
995 */
996
997static inline ppa_struct *find_parent(void)
998{
999 ppa_struct *dev, *par = NULL;
1000 unsigned int cnt = 0;
1001
1002 if (list_empty(&ppa_hosts))
1003 return NULL;
1004
1005 list_for_each_entry(dev, &ppa_hosts, list) {
1006 if (dev->dev_no != cnt)
1007 return par;
1008 cnt++;
1009 par = dev;
1010 }
1011
1012 return par;
1013}
1014
1015static int __ppa_attach(struct parport *pb)
1016{
1017 struct Scsi_Host *host;
1018 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(waiting);
1019 DEFINE_WAIT(wait);
1020 ppa_struct *dev, *temp;
1021 int ports;
1022 int modes, ppb, ppb_hi;
1023 int err = -ENOMEM;
1024 struct pardev_cb ppa_cb;
1025
1026 dev = kzalloc(sizeof(ppa_struct), GFP_KERNEL);
1027 if (!dev)
1028 return -ENOMEM;
1029 dev->base = -1;
1030 dev->mode = PPA_AUTODETECT;
1031 dev->recon_tmo = PPA_RECON_TMO;
1032 init_waitqueue_head(&waiting);
1033 temp = find_parent();
1034 if (temp)
1035 dev->dev_no = temp->dev_no + 1;
1036
1037 memset(&ppa_cb, 0, sizeof(ppa_cb));
1038 ppa_cb.private = dev;
1039 ppa_cb.wakeup = ppa_wakeup;
1040
1041 dev->dev = parport_register_dev_model(pb, "ppa", &ppa_cb, dev->dev_no);
1042
1043 if (!dev->dev)
1044 goto out;
1045
1046 /* Claim the bus so it remembers what we do to the control
1047 * registers. [ CTR and ECP ]
1048 */
1049 err = -EBUSY;
1050 dev->waiting = &waiting;
1051 prepare_to_wait(&waiting, &wait, TASK_UNINTERRUPTIBLE);
1052 if (ppa_pb_claim(dev))
1053 schedule_timeout(3 * HZ);
1054 if (dev->wanted) {
1055 printk(KERN_ERR "ppa%d: failed to claim parport because "
1056 "a pardevice is owning the port for too long "
1057 "time!\n", pb->number);
1058 ppa_pb_dismiss(dev);
1059 dev->waiting = NULL;
1060 finish_wait(&waiting, &wait);
1061 goto out1;
1062 }
1063 dev->waiting = NULL;
1064 finish_wait(&waiting, &wait);
1065 ppb = dev->base = dev->dev->port->base;
1066 ppb_hi = dev->dev->port->base_hi;
1067 w_ctr(ppb, 0x0c);
1068 modes = dev->dev->port->modes;
1069
1070 /* Mode detection works up the chain of speed
1071 * This avoids a nasty if-then-else-if-... tree
1072 */
1073 dev->mode = PPA_NIBBLE;
1074
1075 if (modes & PARPORT_MODE_TRISTATE)
1076 dev->mode = PPA_PS2;
1077
1078 if (modes & PARPORT_MODE_ECP) {
1079 w_ecr(ppb_hi, 0x20);
1080 dev->mode = PPA_PS2;
1081 }
1082 if ((modes & PARPORT_MODE_EPP) && (modes & PARPORT_MODE_ECP))
1083 w_ecr(ppb_hi, 0x80);
1084
1085 /* Done configuration */
1086
1087 err = ppa_init(dev);
1088 ppa_pb_release(dev);
1089
1090 if (err)
1091 goto out1;
1092
1093 /* now the glue ... */
1094 if (dev->mode == PPA_NIBBLE || dev->mode == PPA_PS2)
1095 ports = 3;
1096 else
1097 ports = 8;
1098
1099 INIT_DELAYED_WORK(&dev->ppa_tq, ppa_interrupt);
1100
1101 err = -ENOMEM;
1102 host = scsi_host_alloc(&ppa_template, sizeof(ppa_struct *));
1103 if (!host)
1104 goto out1;
1105 host->io_port = pb->base;
1106 host->n_io_port = ports;
1107 host->dma_channel = -1;
1108 host->unique_id = pb->number;
1109 *(ppa_struct **)&host->hostdata = dev;
1110 dev->host = host;
1111 list_add_tail(&dev->list, &ppa_hosts);
1112 err = scsi_add_host(host, NULL);
1113 if (err)
1114 goto out2;
1115 scsi_scan_host(host);
1116 return 0;
1117out2:
1118 list_del_init(&dev->list);
1119 scsi_host_put(host);
1120out1:
1121 parport_unregister_device(dev->dev);
1122out:
1123 kfree(dev);
1124 return err;
1125}
1126
1127static void ppa_attach(struct parport *pb)
1128{
1129 __ppa_attach(pb);
1130}
1131
1132static void ppa_detach(struct parport *pb)
1133{
1134 ppa_struct *dev;
1135 list_for_each_entry(dev, &ppa_hosts, list) {
1136 if (dev->dev->port == pb) {
1137 list_del_init(&dev->list);
1138 scsi_remove_host(dev->host);
1139 scsi_host_put(dev->host);
1140 parport_unregister_device(dev->dev);
1141 kfree(dev);
1142 break;
1143 }
1144 }
1145}
1146
1147static struct parport_driver ppa_driver = {
1148 .name = "ppa",
1149 .match_port = ppa_attach,
1150 .detach = ppa_detach,
1151 .devmodel = true,
1152};
1153
1154static int __init ppa_driver_init(void)
1155{
1156 printk(KERN_INFO "ppa: Version %s\n", PPA_VERSION);
1157 return parport_register_driver(&ppa_driver);
1158}
1159
1160static void __exit ppa_driver_exit(void)
1161{
1162 parport_unregister_driver(&ppa_driver);
1163}
1164
1165module_init(ppa_driver_init);
1166module_exit(ppa_driver_exit);
1167MODULE_LICENSE("GPL");
1168