1 | /* ppa.c -- low level driver for the IOMEGA PPA3 |
2 | * parallel port SCSI host adapter. |
3 | * |
4 | * (The PPA3 is the embedded controller in the ZIP drive.) |
5 | * |
6 | * (c) 1995,1996 Grant R. Guenther, grant@torque.net, |
7 | * under the terms of the GNU General Public License. |
8 | * |
9 | */ |
10 | |
11 | #include <linux/init.h> |
12 | #include <linux/kernel.h> |
13 | #include <linux/slab.h> |
14 | #include <linux/module.h> |
15 | #include <linux/blkdev.h> |
16 | #include <linux/parport.h> |
17 | #include <linux/workqueue.h> |
18 | #include <linux/delay.h> |
19 | #include <linux/jiffies.h> |
20 | #include <asm/io.h> |
21 | |
22 | #include <scsi/scsi.h> |
23 | #include <scsi/scsi_cmnd.h> |
24 | #include <scsi/scsi_device.h> |
25 | #include <scsi/scsi_host.h> |
26 | |
27 | |
28 | static void ppa_reset_pulse(unsigned int base); |
29 | |
30 | typedef struct { |
31 | struct pardevice *dev; /* Parport device entry */ |
32 | int base; /* Actual port address */ |
33 | int mode; /* Transfer mode */ |
34 | struct scsi_cmnd *cur_cmd; /* Current queued command */ |
35 | struct delayed_work ppa_tq; /* Polling interrupt stuff */ |
36 | unsigned long jstart; /* Jiffies at start */ |
37 | unsigned long recon_tmo; /* How many usecs to wait for reconnection (6th bit) */ |
38 | unsigned int failed:1; /* Failure flag */ |
39 | unsigned wanted:1; /* Parport sharing busy flag */ |
40 | unsigned int dev_no; /* Device number */ |
41 | wait_queue_head_t *waiting; |
42 | struct Scsi_Host *host; |
43 | struct list_head list; |
44 | } ppa_struct; |
45 | |
46 | #include "ppa.h" |
47 | |
48 | static unsigned int mode = PPA_AUTODETECT; |
49 | module_param(mode, uint, 0644); |
50 | MODULE_PARM_DESC(mode, "Transfer mode (0 = Autodetect, 1 = SPP 4-bit, " |
51 | "2 = SPP 8-bit, 3 = EPP 8-bit, 4 = EPP 16-bit, 5 = EPP 32-bit" ); |
52 | |
53 | static struct scsi_pointer *ppa_scsi_pointer(struct scsi_cmnd *cmd) |
54 | { |
55 | return scsi_cmd_priv(cmd); |
56 | } |
57 | |
58 | static inline ppa_struct *ppa_dev(struct Scsi_Host *host) |
59 | { |
60 | return *(ppa_struct **)&host->hostdata; |
61 | } |
62 | |
63 | static DEFINE_SPINLOCK(arbitration_lock); |
64 | |
65 | static void got_it(ppa_struct *dev) |
66 | { |
67 | dev->base = dev->dev->port->base; |
68 | if (dev->cur_cmd) |
69 | ppa_scsi_pointer(cmd: dev->cur_cmd)->phase = 1; |
70 | else |
71 | wake_up(dev->waiting); |
72 | } |
73 | |
74 | static void ppa_wakeup(void *ref) |
75 | { |
76 | ppa_struct *dev = (ppa_struct *) ref; |
77 | unsigned long flags; |
78 | |
79 | spin_lock_irqsave(&arbitration_lock, flags); |
80 | if (dev->wanted) { |
81 | parport_claim(dev: dev->dev); |
82 | got_it(dev); |
83 | dev->wanted = 0; |
84 | } |
85 | spin_unlock_irqrestore(lock: &arbitration_lock, flags); |
86 | return; |
87 | } |
88 | |
89 | static int ppa_pb_claim(ppa_struct *dev) |
90 | { |
91 | unsigned long flags; |
92 | int res = 1; |
93 | spin_lock_irqsave(&arbitration_lock, flags); |
94 | if (parport_claim(dev: dev->dev) == 0) { |
95 | got_it(dev); |
96 | res = 0; |
97 | } |
98 | dev->wanted = res; |
99 | spin_unlock_irqrestore(lock: &arbitration_lock, flags); |
100 | return res; |
101 | } |
102 | |
103 | static void ppa_pb_dismiss(ppa_struct *dev) |
104 | { |
105 | unsigned long flags; |
106 | int wanted; |
107 | spin_lock_irqsave(&arbitration_lock, flags); |
108 | wanted = dev->wanted; |
109 | dev->wanted = 0; |
110 | spin_unlock_irqrestore(lock: &arbitration_lock, flags); |
111 | if (!wanted) |
112 | parport_release(dev: dev->dev); |
113 | } |
114 | |
115 | static inline void ppa_pb_release(ppa_struct *dev) |
116 | { |
117 | parport_release(dev: dev->dev); |
118 | } |
119 | |
120 | /* |
121 | * Start of Chipset kludges |
122 | */ |
123 | |
124 | /* This is to give the ppa driver a way to modify the timings (and other |
125 | * parameters) by writing to the /proc/scsi/ppa/0 file. |
126 | * Very simple method really... (To simple, no error checking :( ) |
127 | * Reason: Kernel hackers HATE having to unload and reload modules for |
128 | * testing... |
129 | * Also gives a method to use a script to obtain optimum timings (TODO) |
130 | */ |
131 | |
132 | static inline int ppa_write_info(struct Scsi_Host *host, char *buffer, int length) |
133 | { |
134 | ppa_struct *dev = ppa_dev(host); |
135 | unsigned long x; |
136 | |
137 | if ((length > 5) && (strncmp(buffer, "mode=" , 5) == 0)) { |
138 | x = simple_strtoul(buffer + 5, NULL, 0); |
139 | dev->mode = x; |
140 | return length; |
141 | } |
142 | if ((length > 10) && (strncmp(buffer, "recon_tmo=" , 10) == 0)) { |
143 | x = simple_strtoul(buffer + 10, NULL, 0); |
144 | dev->recon_tmo = x; |
145 | printk(KERN_INFO "ppa: recon_tmo set to %ld\n" , x); |
146 | return length; |
147 | } |
148 | printk(KERN_WARNING "ppa /proc: invalid variable\n" ); |
149 | return -EINVAL; |
150 | } |
151 | |
152 | static int ppa_show_info(struct seq_file *m, struct Scsi_Host *host) |
153 | { |
154 | ppa_struct *dev = ppa_dev(host); |
155 | |
156 | seq_printf(m, fmt: "Version : %s\n" , PPA_VERSION); |
157 | seq_printf(m, fmt: "Parport : %s\n" , dev->dev->port->name); |
158 | seq_printf(m, fmt: "Mode : %s\n" , PPA_MODE_STRING[dev->mode]); |
159 | #if PPA_DEBUG > 0 |
160 | seq_printf(m, "recon_tmo : %lu\n" , dev->recon_tmo); |
161 | #endif |
162 | return 0; |
163 | } |
164 | |
165 | static int device_check(ppa_struct *dev, bool autodetect); |
166 | |
167 | #if PPA_DEBUG > 0 |
168 | #define ppa_fail(x,y) printk("ppa: ppa_fail(%i) from %s at line %d\n",\ |
169 | y, __func__, __LINE__); ppa_fail_func(x,y); |
170 | static inline void ppa_fail_func(ppa_struct *dev, int error_code) |
171 | #else |
172 | static inline void ppa_fail(ppa_struct *dev, int error_code) |
173 | #endif |
174 | { |
175 | /* If we fail a device then we trash status / message bytes */ |
176 | if (dev->cur_cmd) { |
177 | dev->cur_cmd->result = error_code << 16; |
178 | dev->failed = 1; |
179 | } |
180 | } |
181 | |
182 | /* |
183 | * Wait for the high bit to be set. |
184 | * |
185 | * In principle, this could be tied to an interrupt, but the adapter |
186 | * doesn't appear to be designed to support interrupts. We spin on |
187 | * the 0x80 ready bit. |
188 | */ |
189 | static unsigned char ppa_wait(ppa_struct *dev) |
190 | { |
191 | int k; |
192 | unsigned short ppb = dev->base; |
193 | unsigned char r; |
194 | |
195 | k = PPA_SPIN_TMO; |
196 | /* Wait for bit 6 and 7 - PJC */ |
197 | for (r = r_str(ppb); ((r & 0xc0) != 0xc0) && (k); k--) { |
198 | udelay(1); |
199 | r = r_str(ppb); |
200 | } |
201 | |
202 | /* |
203 | * return some status information. |
204 | * Semantics: 0xc0 = ZIP wants more data |
205 | * 0xd0 = ZIP wants to send more data |
206 | * 0xe0 = ZIP is expecting SCSI command data |
207 | * 0xf0 = end of transfer, ZIP is sending status |
208 | */ |
209 | if (k) |
210 | return (r & 0xf0); |
211 | |
212 | /* Counter expired - Time out occurred */ |
213 | ppa_fail(dev, error_code: DID_TIME_OUT); |
214 | printk(KERN_WARNING "ppa timeout in ppa_wait\n" ); |
215 | return 0; /* command timed out */ |
216 | } |
217 | |
218 | /* |
219 | * Clear EPP Timeout Bit |
220 | */ |
221 | static inline void epp_reset(unsigned short ppb) |
222 | { |
223 | int i; |
224 | |
225 | i = r_str(ppb); |
226 | w_str(ppb, i); |
227 | w_str(ppb, i & 0xfe); |
228 | } |
229 | |
230 | /* |
231 | * Wait for empty ECP fifo (if we are in ECP fifo mode only) |
232 | */ |
233 | static inline void ecp_sync(ppa_struct *dev) |
234 | { |
235 | int i, ppb_hi = dev->dev->port->base_hi; |
236 | |
237 | if (ppb_hi == 0) |
238 | return; |
239 | |
240 | if ((r_ecr(ppb_hi) & 0xe0) == 0x60) { /* mode 011 == ECP fifo mode */ |
241 | for (i = 0; i < 100; i++) { |
242 | if (r_ecr(ppb_hi) & 0x01) |
243 | return; |
244 | udelay(5); |
245 | } |
246 | printk(KERN_WARNING "ppa: ECP sync failed as data still present in FIFO.\n" ); |
247 | } |
248 | } |
249 | |
250 | static int ppa_byte_out(unsigned short base, const char *buffer, int len) |
251 | { |
252 | int i; |
253 | |
254 | for (i = len; i; i--) { |
255 | w_dtr(base, *buffer++); |
256 | w_ctr(base, 0xe); |
257 | w_ctr(base, 0xc); |
258 | } |
259 | return 1; /* All went well - we hope! */ |
260 | } |
261 | |
262 | static int ppa_byte_in(unsigned short base, char *buffer, int len) |
263 | { |
264 | int i; |
265 | |
266 | for (i = len; i; i--) { |
267 | *buffer++ = r_dtr(base); |
268 | w_ctr(base, 0x27); |
269 | w_ctr(base, 0x25); |
270 | } |
271 | return 1; /* All went well - we hope! */ |
272 | } |
273 | |
274 | static int ppa_nibble_in(unsigned short base, char *buffer, int len) |
275 | { |
276 | for (; len; len--) { |
277 | unsigned char h; |
278 | |
279 | w_ctr(base, 0x4); |
280 | h = r_str(base) & 0xf0; |
281 | w_ctr(base, 0x6); |
282 | *buffer++ = h | ((r_str(base) & 0xf0) >> 4); |
283 | } |
284 | return 1; /* All went well - we hope! */ |
285 | } |
286 | |
287 | static int ppa_out(ppa_struct *dev, char *buffer, int len) |
288 | { |
289 | int r; |
290 | unsigned short ppb = dev->base; |
291 | |
292 | r = ppa_wait(dev); |
293 | |
294 | if ((r & 0x50) != 0x40) { |
295 | ppa_fail(dev, error_code: DID_ERROR); |
296 | return 0; |
297 | } |
298 | switch (dev->mode) { |
299 | case PPA_NIBBLE: |
300 | case PPA_PS2: |
301 | /* 8 bit output, with a loop */ |
302 | r = ppa_byte_out(base: ppb, buffer, len); |
303 | break; |
304 | |
305 | case PPA_EPP_32: |
306 | case PPA_EPP_16: |
307 | case PPA_EPP_8: |
308 | epp_reset(ppb); |
309 | w_ctr(ppb, 0x4); |
310 | if (dev->mode == PPA_EPP_32 && !(((long) buffer | len) & 0x03)) |
311 | outsl(port: ppb + 4, addr: buffer, count: len >> 2); |
312 | else if (dev->mode == PPA_EPP_16 && !(((long) buffer | len) & 0x01)) |
313 | outsw(port: ppb + 4, addr: buffer, count: len >> 1); |
314 | else |
315 | outsb(port: ppb + 4, addr: buffer, count: len); |
316 | w_ctr(ppb, 0xc); |
317 | r = !(r_str(ppb) & 0x01); |
318 | w_ctr(ppb, 0xc); |
319 | ecp_sync(dev); |
320 | break; |
321 | |
322 | default: |
323 | printk(KERN_ERR "PPA: bug in ppa_out()\n" ); |
324 | r = 0; |
325 | } |
326 | return r; |
327 | } |
328 | |
329 | static int ppa_in(ppa_struct *dev, char *buffer, int len) |
330 | { |
331 | int r; |
332 | unsigned short ppb = dev->base; |
333 | |
334 | r = ppa_wait(dev); |
335 | |
336 | if ((r & 0x50) != 0x50) { |
337 | ppa_fail(dev, error_code: DID_ERROR); |
338 | return 0; |
339 | } |
340 | switch (dev->mode) { |
341 | case PPA_NIBBLE: |
342 | /* 4 bit input, with a loop */ |
343 | r = ppa_nibble_in(base: ppb, buffer, len); |
344 | w_ctr(ppb, 0xc); |
345 | break; |
346 | |
347 | case PPA_PS2: |
348 | /* 8 bit input, with a loop */ |
349 | w_ctr(ppb, 0x25); |
350 | r = ppa_byte_in(base: ppb, buffer, len); |
351 | w_ctr(ppb, 0x4); |
352 | w_ctr(ppb, 0xc); |
353 | break; |
354 | |
355 | case PPA_EPP_32: |
356 | case PPA_EPP_16: |
357 | case PPA_EPP_8: |
358 | epp_reset(ppb); |
359 | w_ctr(ppb, 0x24); |
360 | if (dev->mode == PPA_EPP_32 && !(((long) buffer | len) & 0x03)) |
361 | insl(port: ppb + 4, addr: buffer, count: len >> 2); |
362 | else if (dev->mode == PPA_EPP_16 && !(((long) buffer | len) & 0x01)) |
363 | insw(port: ppb + 4, addr: buffer, count: len >> 1); |
364 | else |
365 | insb(port: ppb + 4, addr: buffer, count: len); |
366 | w_ctr(ppb, 0x2c); |
367 | r = !(r_str(ppb) & 0x01); |
368 | w_ctr(ppb, 0x2c); |
369 | ecp_sync(dev); |
370 | break; |
371 | |
372 | default: |
373 | printk(KERN_ERR "PPA: bug in ppa_ins()\n" ); |
374 | r = 0; |
375 | break; |
376 | } |
377 | return r; |
378 | } |
379 | |
380 | /* end of ppa_io.h */ |
381 | static inline void ppa_d_pulse(unsigned short ppb, unsigned char b) |
382 | { |
383 | w_dtr(ppb, b); |
384 | w_ctr(ppb, 0xc); |
385 | w_ctr(ppb, 0xe); |
386 | w_ctr(ppb, 0xc); |
387 | w_ctr(ppb, 0x4); |
388 | w_ctr(ppb, 0xc); |
389 | } |
390 | |
391 | static void ppa_disconnect(ppa_struct *dev) |
392 | { |
393 | unsigned short ppb = dev->base; |
394 | |
395 | ppa_d_pulse(ppb, b: 0); |
396 | ppa_d_pulse(ppb, b: 0x3c); |
397 | ppa_d_pulse(ppb, b: 0x20); |
398 | ppa_d_pulse(ppb, b: 0xf); |
399 | } |
400 | |
401 | static inline void ppa_c_pulse(unsigned short ppb, unsigned char b) |
402 | { |
403 | w_dtr(ppb, b); |
404 | w_ctr(ppb, 0x4); |
405 | w_ctr(ppb, 0x6); |
406 | w_ctr(ppb, 0x4); |
407 | w_ctr(ppb, 0xc); |
408 | } |
409 | |
410 | static inline void ppa_connect(ppa_struct *dev, int flag) |
411 | { |
412 | unsigned short ppb = dev->base; |
413 | |
414 | ppa_c_pulse(ppb, b: 0); |
415 | ppa_c_pulse(ppb, b: 0x3c); |
416 | ppa_c_pulse(ppb, b: 0x20); |
417 | if ((flag == CONNECT_EPP_MAYBE) && IN_EPP_MODE(dev->mode)) |
418 | ppa_c_pulse(ppb, b: 0xcf); |
419 | else |
420 | ppa_c_pulse(ppb, b: 0x8f); |
421 | } |
422 | |
423 | static int ppa_select(ppa_struct *dev, int target) |
424 | { |
425 | int k; |
426 | unsigned short ppb = dev->base; |
427 | |
428 | /* |
429 | * Bit 6 (0x40) is the device selected bit. |
430 | * First we must wait till the current device goes off line... |
431 | */ |
432 | k = PPA_SELECT_TMO; |
433 | do { |
434 | k--; |
435 | udelay(1); |
436 | } while ((r_str(ppb) & 0x40) && (k)); |
437 | if (!k) |
438 | return 0; |
439 | |
440 | w_dtr(ppb, (1 << target)); |
441 | w_ctr(ppb, 0xe); |
442 | w_ctr(ppb, 0xc); |
443 | w_dtr(ppb, 0x80); /* This is NOT the initator */ |
444 | w_ctr(ppb, 0x8); |
445 | |
446 | k = PPA_SELECT_TMO; |
447 | do { |
448 | k--; |
449 | udelay(1); |
450 | } |
451 | while (!(r_str(ppb) & 0x40) && (k)); |
452 | if (!k) |
453 | return 0; |
454 | |
455 | return 1; |
456 | } |
457 | |
458 | /* |
459 | * This is based on a trace of what the Iomega DOS 'guest' driver does. |
460 | * I've tried several different kinds of parallel ports with guest and |
461 | * coded this to react in the same ways that it does. |
462 | * |
463 | * The return value from this function is just a hint about where the |
464 | * handshaking failed. |
465 | * |
466 | */ |
467 | static int ppa_init(ppa_struct *dev) |
468 | { |
469 | int retv; |
470 | unsigned short ppb = dev->base; |
471 | bool autodetect = dev->mode == PPA_AUTODETECT; |
472 | |
473 | if (autodetect) { |
474 | int modes = dev->dev->port->modes; |
475 | int ppb_hi = dev->dev->port->base_hi; |
476 | |
477 | /* Mode detection works up the chain of speed |
478 | * This avoids a nasty if-then-else-if-... tree |
479 | */ |
480 | dev->mode = PPA_NIBBLE; |
481 | |
482 | if (modes & PARPORT_MODE_TRISTATE) |
483 | dev->mode = PPA_PS2; |
484 | |
485 | if (modes & PARPORT_MODE_ECP) { |
486 | w_ecr(ppb_hi, 0x20); |
487 | dev->mode = PPA_PS2; |
488 | } |
489 | if ((modes & PARPORT_MODE_EPP) && (modes & PARPORT_MODE_ECP)) |
490 | w_ecr(ppb_hi, 0x80); |
491 | } |
492 | |
493 | ppa_disconnect(dev); |
494 | ppa_connect(dev, CONNECT_NORMAL); |
495 | |
496 | retv = 2; /* Failed */ |
497 | |
498 | w_ctr(ppb, 0xe); |
499 | if ((r_str(ppb) & 0x08) == 0x08) |
500 | retv--; |
501 | |
502 | w_ctr(ppb, 0xc); |
503 | if ((r_str(ppb) & 0x08) == 0x00) |
504 | retv--; |
505 | |
506 | if (!retv) |
507 | ppa_reset_pulse(base: ppb); |
508 | udelay(1000); /* Allow devices to settle down */ |
509 | ppa_disconnect(dev); |
510 | udelay(1000); /* Another delay to allow devices to settle */ |
511 | |
512 | if (retv) |
513 | return -EIO; |
514 | |
515 | return device_check(dev, autodetect); |
516 | } |
517 | |
518 | static inline int ppa_send_command(struct scsi_cmnd *cmd) |
519 | { |
520 | ppa_struct *dev = ppa_dev(host: cmd->device->host); |
521 | int k; |
522 | |
523 | w_ctr(dev->base, 0x0c); |
524 | |
525 | for (k = 0; k < cmd->cmd_len; k++) |
526 | if (!ppa_out(dev, buffer: &cmd->cmnd[k], len: 1)) |
527 | return 0; |
528 | return 1; |
529 | } |
530 | |
531 | /* |
532 | * The bulk flag enables some optimisations in the data transfer loops, |
533 | * it should be true for any command that transfers data in integral |
534 | * numbers of sectors. |
535 | * |
536 | * The driver appears to remain stable if we speed up the parallel port |
537 | * i/o in this function, but not elsewhere. |
538 | */ |
539 | static int ppa_completion(struct scsi_cmnd *const cmd) |
540 | { |
541 | /* Return codes: |
542 | * -1 Error |
543 | * 0 Told to schedule |
544 | * 1 Finished data transfer |
545 | */ |
546 | struct scsi_pointer *scsi_pointer = ppa_scsi_pointer(cmd); |
547 | ppa_struct *dev = ppa_dev(host: cmd->device->host); |
548 | unsigned short ppb = dev->base; |
549 | unsigned long start_jiffies = jiffies; |
550 | |
551 | unsigned char r, v; |
552 | int fast, bulk, status; |
553 | |
554 | v = cmd->cmnd[0]; |
555 | bulk = ((v == READ_6) || |
556 | (v == READ_10) || (v == WRITE_6) || (v == WRITE_10)); |
557 | |
558 | /* |
559 | * We only get here if the drive is ready to comunicate, |
560 | * hence no need for a full ppa_wait. |
561 | */ |
562 | r = (r_str(ppb) & 0xf0); |
563 | |
564 | while (r != (unsigned char) 0xf0) { |
565 | /* |
566 | * If we have been running for more than a full timer tick |
567 | * then take a rest. |
568 | */ |
569 | if (time_after(jiffies, start_jiffies + 1)) |
570 | return 0; |
571 | |
572 | if (scsi_pointer->this_residual <= 0) { |
573 | ppa_fail(dev, error_code: DID_ERROR); |
574 | return -1; /* ERROR_RETURN */ |
575 | } |
576 | |
577 | /* On some hardware we have SCSI disconnected (6th bit low) |
578 | * for about 100usecs. It is too expensive to wait a |
579 | * tick on every loop so we busy wait for no more than |
580 | * 500usecs to give the drive a chance first. We do not |
581 | * change things for "normal" hardware since generally |
582 | * the 6th bit is always high. |
583 | * This makes the CPU load higher on some hardware |
584 | * but otherwise we can not get more than 50K/secs |
585 | * on this problem hardware. |
586 | */ |
587 | if ((r & 0xc0) != 0xc0) { |
588 | /* Wait for reconnection should be no more than |
589 | * jiffy/2 = 5ms = 5000 loops |
590 | */ |
591 | unsigned long k = dev->recon_tmo; |
592 | for (; k && ((r = (r_str(ppb) & 0xf0)) & 0xc0) != 0xc0; |
593 | k--) |
594 | udelay(1); |
595 | |
596 | if (!k) |
597 | return 0; |
598 | } |
599 | |
600 | /* determine if we should use burst I/O */ |
601 | fast = bulk && scsi_pointer->this_residual >= PPA_BURST_SIZE ? |
602 | PPA_BURST_SIZE : 1; |
603 | |
604 | if (r == (unsigned char) 0xc0) |
605 | status = ppa_out(dev, buffer: scsi_pointer->ptr, len: fast); |
606 | else |
607 | status = ppa_in(dev, buffer: scsi_pointer->ptr, len: fast); |
608 | |
609 | scsi_pointer->ptr += fast; |
610 | scsi_pointer->this_residual -= fast; |
611 | |
612 | if (!status) { |
613 | ppa_fail(dev, error_code: DID_BUS_BUSY); |
614 | return -1; /* ERROR_RETURN */ |
615 | } |
616 | if (scsi_pointer->buffer && !scsi_pointer->this_residual) { |
617 | /* if scatter/gather, advance to the next segment */ |
618 | if (scsi_pointer->buffers_residual--) { |
619 | scsi_pointer->buffer = |
620 | sg_next(scsi_pointer->buffer); |
621 | scsi_pointer->this_residual = |
622 | scsi_pointer->buffer->length; |
623 | scsi_pointer->ptr = |
624 | sg_virt(sg: scsi_pointer->buffer); |
625 | } |
626 | } |
627 | /* Now check to see if the drive is ready to comunicate */ |
628 | r = (r_str(ppb) & 0xf0); |
629 | /* If not, drop back down to the scheduler and wait a timer tick */ |
630 | if (!(r & 0x80)) |
631 | return 0; |
632 | } |
633 | return 1; /* FINISH_RETURN */ |
634 | } |
635 | |
636 | /* |
637 | * Since the PPA itself doesn't generate interrupts, we use |
638 | * the scheduler's task queue to generate a stream of call-backs and |
639 | * complete the request when the drive is ready. |
640 | */ |
641 | static void ppa_interrupt(struct work_struct *work) |
642 | { |
643 | ppa_struct *dev = container_of(work, ppa_struct, ppa_tq.work); |
644 | struct scsi_cmnd *cmd = dev->cur_cmd; |
645 | |
646 | if (!cmd) { |
647 | printk(KERN_ERR "PPA: bug in ppa_interrupt\n" ); |
648 | return; |
649 | } |
650 | if (ppa_engine(dev, cmd)) { |
651 | schedule_delayed_work(dwork: &dev->ppa_tq, delay: 1); |
652 | return; |
653 | } |
654 | /* Command must of completed hence it is safe to let go... */ |
655 | #if PPA_DEBUG > 0 |
656 | switch ((cmd->result >> 16) & 0xff) { |
657 | case DID_OK: |
658 | break; |
659 | case DID_NO_CONNECT: |
660 | printk(KERN_DEBUG "ppa: no device at SCSI ID %i\n" , scmd_id(cmd)); |
661 | break; |
662 | case DID_BUS_BUSY: |
663 | printk(KERN_DEBUG "ppa: BUS BUSY - EPP timeout detected\n" ); |
664 | break; |
665 | case DID_TIME_OUT: |
666 | printk(KERN_DEBUG "ppa: unknown timeout\n" ); |
667 | break; |
668 | case DID_ABORT: |
669 | printk(KERN_DEBUG "ppa: told to abort\n" ); |
670 | break; |
671 | case DID_PARITY: |
672 | printk(KERN_DEBUG "ppa: parity error (???)\n" ); |
673 | break; |
674 | case DID_ERROR: |
675 | printk(KERN_DEBUG "ppa: internal driver error\n" ); |
676 | break; |
677 | case DID_RESET: |
678 | printk(KERN_DEBUG "ppa: told to reset device\n" ); |
679 | break; |
680 | case DID_BAD_INTR: |
681 | printk(KERN_WARNING "ppa: bad interrupt (???)\n" ); |
682 | break; |
683 | default: |
684 | printk(KERN_WARNING "ppa: bad return code (%02x)\n" , |
685 | (cmd->result >> 16) & 0xff); |
686 | } |
687 | #endif |
688 | |
689 | if (ppa_scsi_pointer(cmd)->phase > 1) |
690 | ppa_disconnect(dev); |
691 | |
692 | ppa_pb_dismiss(dev); |
693 | |
694 | dev->cur_cmd = NULL; |
695 | |
696 | scsi_done(cmd); |
697 | } |
698 | |
699 | static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd) |
700 | { |
701 | struct scsi_pointer *scsi_pointer = ppa_scsi_pointer(cmd); |
702 | unsigned short ppb = dev->base; |
703 | unsigned char l = 0, h = 0; |
704 | int retv; |
705 | |
706 | /* First check for any errors that may of occurred |
707 | * Here we check for internal errors |
708 | */ |
709 | if (dev->failed) |
710 | return 0; |
711 | |
712 | switch (scsi_pointer->phase) { |
713 | case 0: /* Phase 0 - Waiting for parport */ |
714 | if (time_after(jiffies, dev->jstart + HZ)) { |
715 | /* |
716 | * We waited more than a second |
717 | * for parport to call us |
718 | */ |
719 | ppa_fail(dev, error_code: DID_BUS_BUSY); |
720 | return 0; |
721 | } |
722 | return 1; /* wait until ppa_wakeup claims parport */ |
723 | case 1: /* Phase 1 - Connected */ |
724 | { /* Perform a sanity check for cable unplugged */ |
725 | int retv = 2; /* Failed */ |
726 | |
727 | ppa_connect(dev, CONNECT_EPP_MAYBE); |
728 | |
729 | w_ctr(ppb, 0xe); |
730 | if ((r_str(ppb) & 0x08) == 0x08) |
731 | retv--; |
732 | |
733 | w_ctr(ppb, 0xc); |
734 | if ((r_str(ppb) & 0x08) == 0x00) |
735 | retv--; |
736 | |
737 | if (retv) { |
738 | if (time_after(jiffies, dev->jstart + (1 * HZ))) { |
739 | printk(KERN_ERR "ppa: Parallel port cable is unplugged.\n" ); |
740 | ppa_fail(dev, error_code: DID_BUS_BUSY); |
741 | return 0; |
742 | } else { |
743 | ppa_disconnect(dev); |
744 | return 1; /* Try again in a jiffy */ |
745 | } |
746 | } |
747 | scsi_pointer->phase++; |
748 | } |
749 | fallthrough; |
750 | |
751 | case 2: /* Phase 2 - We are now talking to the scsi bus */ |
752 | if (!ppa_select(dev, scmd_id(cmd))) { |
753 | ppa_fail(dev, error_code: DID_NO_CONNECT); |
754 | return 0; |
755 | } |
756 | scsi_pointer->phase++; |
757 | fallthrough; |
758 | |
759 | case 3: /* Phase 3 - Ready to accept a command */ |
760 | w_ctr(ppb, 0x0c); |
761 | if (!(r_str(ppb) & 0x80)) |
762 | return 1; |
763 | |
764 | if (!ppa_send_command(cmd)) |
765 | return 0; |
766 | scsi_pointer->phase++; |
767 | fallthrough; |
768 | |
769 | case 4: /* Phase 4 - Setup scatter/gather buffers */ |
770 | if (scsi_bufflen(cmd)) { |
771 | scsi_pointer->buffer = scsi_sglist(cmd); |
772 | scsi_pointer->this_residual = |
773 | scsi_pointer->buffer->length; |
774 | scsi_pointer->ptr = sg_virt(sg: scsi_pointer->buffer); |
775 | } else { |
776 | scsi_pointer->buffer = NULL; |
777 | scsi_pointer->this_residual = 0; |
778 | scsi_pointer->ptr = NULL; |
779 | } |
780 | scsi_pointer->buffers_residual = scsi_sg_count(cmd) - 1; |
781 | scsi_pointer->phase++; |
782 | fallthrough; |
783 | |
784 | case 5: /* Phase 5 - Data transfer stage */ |
785 | w_ctr(ppb, 0x0c); |
786 | if (!(r_str(ppb) & 0x80)) |
787 | return 1; |
788 | |
789 | retv = ppa_completion(cmd); |
790 | if (retv == -1) |
791 | return 0; |
792 | if (retv == 0) |
793 | return 1; |
794 | scsi_pointer->phase++; |
795 | fallthrough; |
796 | |
797 | case 6: /* Phase 6 - Read status/message */ |
798 | cmd->result = DID_OK << 16; |
799 | /* Check for data overrun */ |
800 | if (ppa_wait(dev) != (unsigned char) 0xf0) { |
801 | ppa_fail(dev, error_code: DID_ERROR); |
802 | return 0; |
803 | } |
804 | if (ppa_in(dev, buffer: &l, len: 1)) { /* read status byte */ |
805 | /* Check for optional message byte */ |
806 | if (ppa_wait(dev) == (unsigned char) 0xf0) |
807 | ppa_in(dev, buffer: &h, len: 1); |
808 | cmd->result = |
809 | (DID_OK << 16) + (h << 8) + (l & STATUS_MASK); |
810 | } |
811 | return 0; /* Finished */ |
812 | |
813 | default: |
814 | printk(KERN_ERR "ppa: Invalid scsi phase\n" ); |
815 | } |
816 | return 0; |
817 | } |
818 | |
819 | static int ppa_queuecommand_lck(struct scsi_cmnd *cmd) |
820 | { |
821 | ppa_struct *dev = ppa_dev(host: cmd->device->host); |
822 | |
823 | if (dev->cur_cmd) { |
824 | printk(KERN_ERR "PPA: bug in ppa_queuecommand\n" ); |
825 | return 0; |
826 | } |
827 | dev->failed = 0; |
828 | dev->jstart = jiffies; |
829 | dev->cur_cmd = cmd; |
830 | cmd->result = DID_ERROR << 16; /* default return code */ |
831 | ppa_scsi_pointer(cmd)->phase = 0; /* bus free */ |
832 | |
833 | schedule_delayed_work(dwork: &dev->ppa_tq, delay: 0); |
834 | |
835 | ppa_pb_claim(dev); |
836 | |
837 | return 0; |
838 | } |
839 | |
840 | static DEF_SCSI_QCMD(ppa_queuecommand) |
841 | |
842 | /* |
843 | * Apparently the disk->capacity attribute is off by 1 sector |
844 | * for all disk drives. We add the one here, but it should really |
845 | * be done in sd.c. Even if it gets fixed there, this will still |
846 | * work. |
847 | */ |
848 | static int ppa_biosparam(struct scsi_device *sdev, struct block_device *dev, |
849 | sector_t capacity, int ip[]) |
850 | { |
851 | ip[0] = 0x40; |
852 | ip[1] = 0x20; |
853 | ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]); |
854 | if (ip[2] > 1024) { |
855 | ip[0] = 0xff; |
856 | ip[1] = 0x3f; |
857 | ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]); |
858 | if (ip[2] > 1023) |
859 | ip[2] = 1023; |
860 | } |
861 | return 0; |
862 | } |
863 | |
864 | static int ppa_abort(struct scsi_cmnd *cmd) |
865 | { |
866 | ppa_struct *dev = ppa_dev(host: cmd->device->host); |
867 | /* |
868 | * There is no method for aborting commands since Iomega |
869 | * have tied the SCSI_MESSAGE line high in the interface |
870 | */ |
871 | |
872 | switch (ppa_scsi_pointer(cmd)->phase) { |
873 | case 0: /* Do not have access to parport */ |
874 | case 1: /* Have not connected to interface */ |
875 | dev->cur_cmd = NULL; /* Forget the problem */ |
876 | return SUCCESS; |
877 | default: /* SCSI command sent, can not abort */ |
878 | return FAILED; |
879 | } |
880 | } |
881 | |
882 | static void ppa_reset_pulse(unsigned int base) |
883 | { |
884 | w_dtr(base, 0x40); |
885 | w_ctr(base, 0x8); |
886 | udelay(30); |
887 | w_ctr(base, 0xc); |
888 | } |
889 | |
890 | static int ppa_reset(struct scsi_cmnd *cmd) |
891 | { |
892 | ppa_struct *dev = ppa_dev(host: cmd->device->host); |
893 | |
894 | if (ppa_scsi_pointer(cmd)->phase) |
895 | ppa_disconnect(dev); |
896 | dev->cur_cmd = NULL; /* Forget the problem */ |
897 | |
898 | ppa_connect(dev, CONNECT_NORMAL); |
899 | ppa_reset_pulse(base: dev->base); |
900 | mdelay(1); /* device settle delay */ |
901 | ppa_disconnect(dev); |
902 | mdelay(1); /* device settle delay */ |
903 | return SUCCESS; |
904 | } |
905 | |
906 | static int device_check(ppa_struct *dev, bool autodetect) |
907 | { |
908 | /* This routine looks for a device and then attempts to use EPP |
909 | to send a command. If all goes as planned then EPP is available. */ |
910 | |
911 | static u8 cmd[6] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; |
912 | int loop, old_mode, status, k, ppb = dev->base; |
913 | unsigned char l; |
914 | |
915 | old_mode = dev->mode; |
916 | for (loop = 0; loop < 8; loop++) { |
917 | /* Attempt to use EPP for Test Unit Ready */ |
918 | if (autodetect && (ppb & 0x0007) == 0x0000) |
919 | dev->mode = PPA_EPP_8; |
920 | |
921 | second_pass: |
922 | ppa_connect(dev, CONNECT_EPP_MAYBE); |
923 | /* Select SCSI device */ |
924 | if (!ppa_select(dev, target: loop)) { |
925 | ppa_disconnect(dev); |
926 | continue; |
927 | } |
928 | printk(KERN_INFO "ppa: Found device at ID %i, Attempting to use %s\n" , |
929 | loop, PPA_MODE_STRING[dev->mode]); |
930 | |
931 | /* Send SCSI command */ |
932 | status = 1; |
933 | w_ctr(ppb, 0x0c); |
934 | for (l = 0; (l < 6) && (status); l++) |
935 | status = ppa_out(dev, buffer: cmd, len: 1); |
936 | |
937 | if (!status) { |
938 | ppa_disconnect(dev); |
939 | ppa_connect(dev, CONNECT_EPP_MAYBE); |
940 | w_dtr(ppb, 0x40); |
941 | w_ctr(ppb, 0x08); |
942 | udelay(30); |
943 | w_ctr(ppb, 0x0c); |
944 | udelay(1000); |
945 | ppa_disconnect(dev); |
946 | udelay(1000); |
947 | if (dev->mode != old_mode) { |
948 | dev->mode = old_mode; |
949 | goto second_pass; |
950 | } |
951 | return -EIO; |
952 | } |
953 | w_ctr(ppb, 0x0c); |
954 | k = 1000000; /* 1 Second */ |
955 | do { |
956 | l = r_str(ppb); |
957 | k--; |
958 | udelay(1); |
959 | } while (!(l & 0x80) && (k)); |
960 | |
961 | l &= 0xf0; |
962 | |
963 | if (l != 0xf0) { |
964 | ppa_disconnect(dev); |
965 | ppa_connect(dev, CONNECT_EPP_MAYBE); |
966 | ppa_reset_pulse(base: ppb); |
967 | udelay(1000); |
968 | ppa_disconnect(dev); |
969 | udelay(1000); |
970 | if (dev->mode != old_mode) { |
971 | dev->mode = old_mode; |
972 | goto second_pass; |
973 | } |
974 | return -EIO; |
975 | } |
976 | ppa_disconnect(dev); |
977 | printk(KERN_INFO "ppa: Communication established with ID %i using %s\n" , |
978 | loop, PPA_MODE_STRING[dev->mode]); |
979 | ppa_connect(dev, CONNECT_EPP_MAYBE); |
980 | ppa_reset_pulse(base: ppb); |
981 | udelay(1000); |
982 | ppa_disconnect(dev); |
983 | udelay(1000); |
984 | return 0; |
985 | } |
986 | return -ENODEV; |
987 | } |
988 | |
989 | static int ppa_adjust_queue(struct scsi_device *device) |
990 | { |
991 | blk_queue_bounce_limit(q: device->request_queue, limit: BLK_BOUNCE_HIGH); |
992 | return 0; |
993 | } |
994 | |
995 | static const struct scsi_host_template ppa_template = { |
996 | .module = THIS_MODULE, |
997 | .proc_name = "ppa" , |
998 | .show_info = ppa_show_info, |
999 | .write_info = ppa_write_info, |
1000 | .name = "Iomega VPI0 (ppa) interface" , |
1001 | .queuecommand = ppa_queuecommand, |
1002 | .eh_abort_handler = ppa_abort, |
1003 | .eh_host_reset_handler = ppa_reset, |
1004 | .bios_param = ppa_biosparam, |
1005 | .this_id = -1, |
1006 | .sg_tablesize = SG_ALL, |
1007 | .can_queue = 1, |
1008 | .slave_alloc = ppa_adjust_queue, |
1009 | .cmd_size = sizeof(struct scsi_pointer), |
1010 | }; |
1011 | |
1012 | /*************************************************************************** |
1013 | * Parallel port probing routines * |
1014 | ***************************************************************************/ |
1015 | |
1016 | static LIST_HEAD(ppa_hosts); |
1017 | |
1018 | /* |
1019 | * Finds the first available device number that can be alloted to the |
1020 | * new ppa device and returns the address of the previous node so that |
1021 | * we can add to the tail and have a list in the ascending order. |
1022 | */ |
1023 | |
1024 | static inline ppa_struct *find_parent(void) |
1025 | { |
1026 | ppa_struct *dev, *par = NULL; |
1027 | unsigned int cnt = 0; |
1028 | |
1029 | if (list_empty(head: &ppa_hosts)) |
1030 | return NULL; |
1031 | |
1032 | list_for_each_entry(dev, &ppa_hosts, list) { |
1033 | if (dev->dev_no != cnt) |
1034 | return par; |
1035 | cnt++; |
1036 | par = dev; |
1037 | } |
1038 | |
1039 | return par; |
1040 | } |
1041 | |
1042 | static int __ppa_attach(struct parport *pb) |
1043 | { |
1044 | struct Scsi_Host *host; |
1045 | DECLARE_WAIT_QUEUE_HEAD_ONSTACK(waiting); |
1046 | DEFINE_WAIT(wait); |
1047 | ppa_struct *dev, *temp; |
1048 | int ports; |
1049 | int err = -ENOMEM; |
1050 | struct pardev_cb ppa_cb; |
1051 | |
1052 | dev = kzalloc(size: sizeof(ppa_struct), GFP_KERNEL); |
1053 | if (!dev) |
1054 | return -ENOMEM; |
1055 | dev->base = -1; |
1056 | dev->mode = mode < PPA_UNKNOWN ? mode : PPA_AUTODETECT; |
1057 | dev->recon_tmo = PPA_RECON_TMO; |
1058 | init_waitqueue_head(&waiting); |
1059 | temp = find_parent(); |
1060 | if (temp) |
1061 | dev->dev_no = temp->dev_no + 1; |
1062 | |
1063 | memset(&ppa_cb, 0, sizeof(ppa_cb)); |
1064 | ppa_cb.private = dev; |
1065 | ppa_cb.wakeup = ppa_wakeup; |
1066 | |
1067 | dev->dev = parport_register_dev_model(port: pb, name: "ppa" , par_dev_cb: &ppa_cb, cnt: dev->dev_no); |
1068 | |
1069 | if (!dev->dev) |
1070 | goto out; |
1071 | |
1072 | /* Claim the bus so it remembers what we do to the control |
1073 | * registers. [ CTR and ECP ] |
1074 | */ |
1075 | err = -EBUSY; |
1076 | dev->waiting = &waiting; |
1077 | prepare_to_wait(wq_head: &waiting, wq_entry: &wait, TASK_UNINTERRUPTIBLE); |
1078 | if (ppa_pb_claim(dev)) |
1079 | schedule_timeout(timeout: 3 * HZ); |
1080 | if (dev->wanted) { |
1081 | printk(KERN_ERR "ppa%d: failed to claim parport because " |
1082 | "a pardevice is owning the port for too long " |
1083 | "time!\n" , pb->number); |
1084 | ppa_pb_dismiss(dev); |
1085 | dev->waiting = NULL; |
1086 | finish_wait(wq_head: &waiting, wq_entry: &wait); |
1087 | goto out1; |
1088 | } |
1089 | dev->waiting = NULL; |
1090 | finish_wait(wq_head: &waiting, wq_entry: &wait); |
1091 | dev->base = dev->dev->port->base; |
1092 | w_ctr(dev->base, 0x0c); |
1093 | |
1094 | /* Done configuration */ |
1095 | |
1096 | err = ppa_init(dev); |
1097 | ppa_pb_release(dev); |
1098 | |
1099 | if (err) |
1100 | goto out1; |
1101 | |
1102 | /* now the glue ... */ |
1103 | if (dev->mode == PPA_NIBBLE || dev->mode == PPA_PS2) |
1104 | ports = 3; |
1105 | else |
1106 | ports = 8; |
1107 | |
1108 | INIT_DELAYED_WORK(&dev->ppa_tq, ppa_interrupt); |
1109 | |
1110 | err = -ENOMEM; |
1111 | host = scsi_host_alloc(&ppa_template, sizeof(ppa_struct *)); |
1112 | if (!host) |
1113 | goto out1; |
1114 | host->io_port = pb->base; |
1115 | host->n_io_port = ports; |
1116 | host->dma_channel = -1; |
1117 | host->unique_id = pb->number; |
1118 | *(ppa_struct **)&host->hostdata = dev; |
1119 | dev->host = host; |
1120 | list_add_tail(new: &dev->list, head: &ppa_hosts); |
1121 | err = scsi_add_host(host, NULL); |
1122 | if (err) |
1123 | goto out2; |
1124 | scsi_scan_host(host); |
1125 | return 0; |
1126 | out2: |
1127 | list_del_init(entry: &dev->list); |
1128 | scsi_host_put(t: host); |
1129 | out1: |
1130 | parport_unregister_device(dev: dev->dev); |
1131 | out: |
1132 | kfree(objp: dev); |
1133 | return err; |
1134 | } |
1135 | |
1136 | static void ppa_attach(struct parport *pb) |
1137 | { |
1138 | __ppa_attach(pb); |
1139 | } |
1140 | |
1141 | static void ppa_detach(struct parport *pb) |
1142 | { |
1143 | ppa_struct *dev; |
1144 | list_for_each_entry(dev, &ppa_hosts, list) { |
1145 | if (dev->dev->port == pb) { |
1146 | list_del_init(entry: &dev->list); |
1147 | scsi_remove_host(dev->host); |
1148 | scsi_host_put(t: dev->host); |
1149 | parport_unregister_device(dev: dev->dev); |
1150 | kfree(objp: dev); |
1151 | break; |
1152 | } |
1153 | } |
1154 | } |
1155 | |
1156 | static struct parport_driver ppa_driver = { |
1157 | .name = "ppa" , |
1158 | .match_port = ppa_attach, |
1159 | .detach = ppa_detach, |
1160 | .devmodel = true, |
1161 | }; |
1162 | module_parport_driver(ppa_driver); |
1163 | |
1164 | MODULE_LICENSE("GPL" ); |
1165 | |