File: /usr/src/linux/drivers/block/paride/pg.c
1 /*
2 pg.c (c) 1998 Grant R. Guenther <grant@torque.net>
3 Under the terms of the GNU General Public License.
4
5 The pg driver provides a simple character device interface for
6 sending ATAPI commands to a device. With the exception of the
7 ATAPI reset operation, all operations are performed by a pair
8 of read and write operations to the appropriate /dev/pgN device.
9 A write operation delivers a command and any outbound data in
10 a single buffer. Normally, the write will succeed unless the
11 device is offline or malfunctioning, or there is already another
12 command pending. If the write succeeds, it should be followed
13 immediately by a read operation, to obtain any returned data and
14 status information. A read will fail if there is no operation
15 in progress.
16
17 As a special case, the device can be reset with a write operation,
18 and in this case, no following read is expected, or permitted.
19
20 There are no ioctl() operations. Any single operation
21 may transfer at most PG_MAX_DATA bytes. Note that the driver must
22 copy the data through an internal buffer. In keeping with all
23 current ATAPI devices, command packets are assumed to be exactly
24 12 bytes in length.
25
26 To permit future changes to this interface, the headers in the
27 read and write buffers contain a single character "magic" flag.
28 Currently this flag must be the character "P".
29
30 By default, the driver will autoprobe for a single parallel
31 port ATAPI device, but if their individual parameters are
32 specified, the driver can handle up to 4 devices.
33
34 To use this device, you must have the following device
35 special files defined:
36
37 /dev/pg0 c 97 0
38 /dev/pg1 c 97 1
39 /dev/pg2 c 97 2
40 /dev/pg3 c 97 3
41
42 (You'll need to change the 97 to something else if you use
43 the 'major' parameter to install the driver on a different
44 major number.)
45
46 The behaviour of the pg driver can be altered by setting
47 some parameters from the insmod command line. The following
48 parameters are adjustable:
49
50 drive0 These four arguments can be arrays of
51 drive1 1-6 integers as follows:
52 drive2
53 drive3 <prt>,<pro>,<uni>,<mod>,<slv>,<dly>
54
55 Where,
56
57 <prt> is the base of the parallel port address for
58 the corresponding drive. (required)
59
60 <pro> is the protocol number for the adapter that
61 supports this drive. These numbers are
62 logged by 'paride' when the protocol modules
63 are initialised. (0 if not given)
64
65 <uni> for those adapters that support chained
66 devices, this is the unit selector for the
67 chain of devices on the given port. It should
68 be zero for devices that don't support chaining.
69 (0 if not given)
70
71 <mod> this can be -1 to choose the best mode, or one
72 of the mode numbers supported by the adapter.
73 (-1 if not given)
74
75 <slv> ATAPI devices can be jumpered to master or slave.
76 Set this to 0 to choose the master drive, 1 to
77 choose the slave, -1 (the default) to choose the
78 first drive found.
79
80 <dly> some parallel ports require the driver to
81 go more slowly. -1 sets a default value that
82 should work with the chosen protocol. Otherwise,
83 set this to a small integer, the larger it is
84 the slower the port i/o. In some cases, setting
85 this to zero will speed up the device. (default -1)
86
87 major You may use this parameter to overide the
88 default major number (97) that this driver
89 will use. Be sure to change the device
90 name as well.
91
92 name This parameter is a character string that
93 contains the name the kernel will use for this
94 device (in /proc output, for instance).
95 (default "pg").
96
97 verbose This parameter controls the amount of logging
98 that is done by the driver. Set it to 0 for
99 quiet operation, to 1 to enable progress
100 messages while the driver probes for devices,
101 or to 2 for full debug logging. (default 0)
102
103 If this driver is built into the kernel, you can use
104 the following command line parameters, with the same values
105 as the corresponding module parameters listed above:
106
107 pg.drive0
108 pg.drive1
109 pg.drive2
110 pg.drive3
111
112 In addition, you can use the parameter pg.disable to disable
113 the driver entirely.
114
115 */
116
117 /* Changes:
118
119 1.01 GRG 1998.06.16 Bug fixes
120 1.02 GRG 1998.09.24 Added jumbo support
121
122 */
123
124 #define PG_VERSION "1.02"
125 #define PG_MAJOR 97
126 #define PG_NAME "pg"
127 #define PG_UNITS 4
128
129 #ifndef PI_PG
130 #define PI_PG 4
131 #endif
132
133 /* Here are things one can override from the insmod command.
134 Most are autoprobed by paride unless set here. Verbose is 0
135 by default.
136
137 */
138
139 static int verbose = 0;
140 static int major = PG_MAJOR;
141 static char *name = PG_NAME;
142 static int disable = 0;
143
144 static int drive0[6] = {0,0,0,-1,-1,-1};
145 static int drive1[6] = {0,0,0,-1,-1,-1};
146 static int drive2[6] = {0,0,0,-1,-1,-1};
147 static int drive3[6] = {0,0,0,-1,-1,-1};
148
149 static int (*drives[4])[6] = {&drive0,&drive1,&drive2,&drive3};
150 static int pg_drive_count;
151
152 #define D_PRT 0
153 #define D_PRO 1
154 #define D_UNI 2
155 #define D_MOD 3
156 #define D_SLV 4
157 #define D_DLY 5
158
159 #define DU (*drives[unit])
160
161 /* end of parameters */
162
163
164 #include <linux/module.h>
165 #include <linux/errno.h>
166 #include <linux/fs.h>
167 #include <linux/devfs_fs_kernel.h>
168 #include <linux/kernel.h>
169 #include <linux/delay.h>
170 #include <linux/slab.h>
171 #include <linux/mtio.h>
172 #include <linux/pg.h>
173 #include <linux/wait.h>
174 #include <linux/smp_lock.h>
175
176 #include <asm/uaccess.h>
177
178 #ifndef MODULE
179
180 #include "setup.h"
181
182 static STT pg_stt[5] = {{"drive0",6,drive0},
183 {"drive1",6,drive1},
184 {"drive2",6,drive2},
185 {"drive3",6,drive3},
186 {"disable",1,&disable}};
187
188 void pg_setup( char *str, int *ints)
189
190 { generic_setup(pg_stt,5,str);
191 }
192
193 #endif
194
195 MODULE_PARM(verbose,"i");
196 MODULE_PARM(major,"i");
197 MODULE_PARM(name,"s");
198 MODULE_PARM(drive0,"1-6i");
199 MODULE_PARM(drive1,"1-6i");
200 MODULE_PARM(drive2,"1-6i");
201 MODULE_PARM(drive3,"1-6i");
202
203 #include "paride.h"
204
205 #define PG_SPIN_DEL 50 /* spin delay in micro-seconds */
206 #define PG_SPIN 200
207 #define PG_TMO HZ
208 #define PG_RESET_TMO 10*HZ
209
210 #define STAT_ERR 0x01
211 #define STAT_INDEX 0x02
212 #define STAT_ECC 0x04
213 #define STAT_DRQ 0x08
214 #define STAT_SEEK 0x10
215 #define STAT_WRERR 0x20
216 #define STAT_READY 0x40
217 #define STAT_BUSY 0x80
218
219 #define ATAPI_IDENTIFY 0x12
220
221 int pg_init(void);
222 #ifdef MODULE
223 void cleanup_module( void );
224 #endif
225
226 static int pg_open(struct inode *inode, struct file *file);
227 static int pg_release (struct inode *inode, struct file *file);
228 static ssize_t pg_read(struct file * filp, char * buf,
229 size_t count, loff_t *ppos);
230 static ssize_t pg_write(struct file * filp, const char * buf,
231 size_t count, loff_t *ppos);
232 static int pg_detect(void);
233
234 static int pg_identify (int unit, int log);
235
236 #define PG_NAMELEN 8
237
238 struct pg_unit {
239 struct pi_adapter pia; /* interface to paride layer */
240 struct pi_adapter *pi;
241 int busy; /* write done, read expected */
242 int start; /* jiffies at command start */
243 int dlen; /* transfer size requested */
244 int timeout; /* timeout requested */
245 int status; /* last sense key */
246 int drive; /* drive */
247 int access; /* count of active opens ... */
248 int present; /* device present ? */
249 char *bufptr;
250 char name[PG_NAMELEN]; /* pg0, pg1, ... */
251 };
252
253 struct pg_unit pg[PG_UNITS];
254
255 /* 'unit' must be defined in all functions - either as a local or a param */
256
257 #define PG pg[unit]
258 #define PI PG.pi
259
260 static char pg_scratch[512]; /* scratch block buffer */
261
262 /* kernel glue structures */
263
264 static struct file_operations pg_fops = {
265 owner: THIS_MODULE,
266 read: pg_read,
267 write: pg_write,
268 open: pg_open,
269 release: pg_release,
270 };
271
272 void pg_init_units( void )
273
274 { int unit, j;
275
276 pg_drive_count = 0;
277 for (unit=0;unit<PG_UNITS;unit++) {
278 PG.pi = & PG.pia;
279 PG.access = 0;
280 PG.busy = 0;
281 PG.present = 0;
282 PG.bufptr = NULL;
283 PG.drive = DU[D_SLV];
284 j = 0;
285 while ((j < PG_NAMELEN-2) && (PG.name[j]=name[j])) j++;
286 PG.name[j++] = '0' + unit;
287 PG.name[j] = 0;
288 if (DU[D_PRT]) pg_drive_count++;
289 }
290 }
291
292 static devfs_handle_t devfs_handle;
293
294 int pg_init (void) /* preliminary initialisation */
295
296 { int unit;
297
298 if (disable) return -1;
299
300 pg_init_units();
301
302 if (pg_detect()) return -1;
303
304 if (devfs_register_chrdev(major,name,&pg_fops)) {
305 printk("pg_init: unable to get major number %d\n",
306 major);
307 for (unit=0;unit<PG_UNITS;unit++)
308 if (PG.present) pi_release(PI);
309 return -1;
310 }
311 devfs_handle = devfs_mk_dir (NULL, "pg", NULL);
312 devfs_register_series (devfs_handle, "%u", 4, DEVFS_FL_DEFAULT,
313 major, 0, S_IFCHR | S_IRUSR | S_IWUSR,
314 &pg_fops, NULL);
315 return 0;
316 }
317
318 #ifdef MODULE
319
320 /* Glue for modules ... */
321
322 void cleanup_module(void);
323
324 int init_module(void)
325
326 { int err;
327
328 #ifdef PARIDE_JUMBO
329 { extern paride_init();
330 paride_init();
331 }
332 #endif
333
334 err = pg_init();
335
336 return err;
337 }
338
339 void cleanup_module(void)
340
341 { int unit;
342
343 devfs_unregister (devfs_handle);
344 devfs_unregister_chrdev(major,name);
345
346 for (unit=0;unit<PG_UNITS;unit++)
347 if (PG.present) pi_release(PI);
348 }
349
350 #endif
351
352 #define WR(c,r,v) pi_write_regr(PI,c,r,v)
353 #define RR(c,r) (pi_read_regr(PI,c,r))
354
355 #define DRIVE (0xa0+0x10*PG.drive)
356
357 static void pg_sleep( int cs )
358
359 { current->state = TASK_INTERRUPTIBLE;
360 schedule_timeout(cs);
361 }
362
363 static int pg_wait( int unit, int go, int stop, int tmo, char * msg )
364
365 { int j, r, e, s, p;
366
367 PG.status = 0;
368
369 j = 0;
370 while ((((r=RR(1,6))&go)||(stop&&(!(r&stop))))&&(time_before(jiffies,tmo))) {
371 if (j++ < PG_SPIN) udelay(PG_SPIN_DEL);
372 else pg_sleep(1);
373 }
374
375 if ((r&(STAT_ERR&stop))||time_after_eq(jiffies, tmo)) {
376 s = RR(0,7);
377 e = RR(0,1);
378 p = RR(0,2);
379 if (verbose > 1)
380 printk("%s: %s: stat=0x%x err=0x%x phase=%d%s\n",
381 PG.name,msg,s,e,p,time_after_eq(jiffies, tmo)?" timeout":"");
382
383
384 if (time_after_eq(jiffies, tmo)) e |= 0x100;
385 PG.status = (e >> 4) & 0xff;
386 return -1;
387 }
388 return 0;
389 }
390
391 static int pg_command( int unit, char * cmd, int dlen, int tmo )
392
393 { int k;
394
395 pi_connect(PI);
396
397 WR(0,6,DRIVE);
398
399 if (pg_wait(unit,STAT_BUSY|STAT_DRQ,0,tmo,"before command")) {
400 pi_disconnect(PI);
401 return -1;
402 }
403
404 WR(0,4,dlen % 256);
405 WR(0,5,dlen / 256);
406 WR(0,7,0xa0); /* ATAPI packet command */
407
408 if (pg_wait(unit,STAT_BUSY,STAT_DRQ,tmo,"command DRQ")) {
409 pi_disconnect(PI);
410 return -1;
411 }
412
413 if (RR(0,2) != 1) {
414 printk("%s: command phase error\n",PG.name);
415 pi_disconnect(PI);
416 return -1;
417 }
418
419 pi_write_block(PI,cmd,12);
420
421 if (verbose > 1) {
422 printk("%s: Command sent, dlen=%d packet= ", PG.name,dlen);
423 for (k=0;k<12;k++) printk("%02x ",cmd[k]&0xff);
424 printk("\n");
425 }
426 return 0;
427 }
428
429 static int pg_completion( int unit, char * buf, int tmo)
430
431 { int r, d, n, p;
432
433 r = pg_wait(unit,STAT_BUSY,STAT_DRQ|STAT_READY|STAT_ERR,
434 tmo,"completion");
435
436 PG.dlen = 0;
437
438 while (RR(0,7)&STAT_DRQ) {
439 d = (RR(0,4)+256*RR(0,5));
440 n = ((d+3)&0xfffc);
441 p = RR(0,2)&3;
442 if (p == 0) pi_write_block(PI,buf,n);
443 if (p == 2) pi_read_block(PI,buf,n);
444 if (verbose > 1) printk("%s: %s %d bytes\n",PG.name,
445 p?"Read":"Write",n);
446 PG.dlen += (1-p)*d;
447 buf += d;
448 r = pg_wait(unit,STAT_BUSY,STAT_DRQ|STAT_READY|STAT_ERR,
449 tmo,"completion");
450 }
451
452 pi_disconnect(PI);
453
454 return r;
455 }
456
457 static int pg_reset( int unit )
458
459 { int i, k, flg;
460 int expect[5] = {1,1,1,0x14,0xeb};
461
462 pi_connect(PI);
463 WR(0,6,DRIVE);
464 WR(0,7,8);
465
466 pg_sleep(20*HZ/1000);
467
468 k = 0;
469 while ((k++ < PG_RESET_TMO) && (RR(1,6)&STAT_BUSY))
470 pg_sleep(1);
471
472 flg = 1;
473 for(i=0;i<5;i++) flg &= (RR(0,i+1) == expect[i]);
474
475 if (verbose) {
476 printk("%s: Reset (%d) signature = ",PG.name,k);
477 for (i=0;i<5;i++) printk("%3x",RR(0,i+1));
478 if (!flg) printk(" (incorrect)");
479 printk("\n");
480 }
481
482 pi_disconnect(PI);
483 return flg-1;
484 }
485
486 static void xs( char *buf, char *targ, int offs, int len )
487
488 { int j,k,l;
489
490 j=0; l=0;
491 for (k=0;k<len;k++)
492 if((buf[k+offs]!=0x20)||(buf[k+offs]!=l))
493 l=targ[j++]=buf[k+offs];
494 if (l==0x20) j--; targ[j]=0;
495 }
496
497 static int pg_identify( int unit, int log )
498
499 { int s;
500 char *ms[2] = {"master","slave"};
501 char mf[10], id[18];
502 char id_cmd[12] = { ATAPI_IDENTIFY,0,0,0,36,0,0,0,0,0,0,0};
503 char buf[36];
504
505 s = pg_command(unit,id_cmd,36,jiffies+PG_TMO);
506 if (s) return -1;
507 s = pg_completion(unit,buf,jiffies+PG_TMO);
508 if (s) return -1;
509
510 if (log) {
511 xs(buf,mf,8,8);
512 xs(buf,id,16,16);
513 printk("%s: %s %s, %s\n",PG.name,mf,id,ms[PG.drive]);
514 }
515
516 return 0;
517 }
518
519 static int pg_probe( int unit )
520
521 /* returns 0, with id set if drive is detected
522 -1, if drive detection failed
523 */
524
525 { if (PG.drive == -1) {
526 for (PG.drive=0;PG.drive<=1;PG.drive++)
527 if (!pg_reset(unit)) return pg_identify(unit,1);
528 } else {
529 if (!pg_reset(unit)) return pg_identify(unit,1);
530 }
531 return -1;
532 }
533
534 static int pg_detect( void )
535
536 { int k, unit;
537
538 printk("%s: %s version %s, major %d\n",
539 name,name,PG_VERSION,major);
540
541 k = 0;
542 if (pg_drive_count == 0) {
543 unit = 0;
544 if (pi_init(PI,1,-1,-1,-1,-1,-1,pg_scratch,
545 PI_PG,verbose,PG.name)) {
546 if (!pg_probe(unit)) {
547 PG.present = 1;
548 k++;
549 } else pi_release(PI);
550 }
551
552 } else for (unit=0;unit<PG_UNITS;unit++) if (DU[D_PRT])
553 if (pi_init(PI,0,DU[D_PRT],DU[D_MOD],DU[D_UNI],
554 DU[D_PRO],DU[D_DLY],pg_scratch,PI_PG,verbose,
555 PG.name)) {
556 if (!pg_probe(unit)) {
557 PG.present = 1;
558 k++;
559 } else pi_release(PI);
560 }
561
562 if (k) return 0;
563
564 printk("%s: No ATAPI device detected\n",name);
565 return -1;
566 }
567
568 #define DEVICE_NR(dev) (MINOR(dev) % 128)
569
570 static int pg_open (struct inode *inode, struct file *file)
571
572 { int unit = DEVICE_NR(inode->i_rdev);
573
574 if ((unit >= PG_UNITS) || (!PG.present)) return -ENODEV;
575
576 PG.access++;
577
578 if (PG.access > 1) {
579 PG.access--;
580 return -EBUSY;
581 }
582
583 if (PG.busy) {
584 pg_reset(unit);
585 PG.busy = 0;
586 }
587
588 pg_identify(unit,(verbose>1));
589
590
591 PG.bufptr = kmalloc(PG_MAX_DATA,GFP_KERNEL);
592 if (PG.bufptr == NULL) {
593 PG.access--;
594 printk("%s: buffer allocation failed\n",PG.name);
595 return -ENOMEM;
596 }
597
598 return 0;
599 }
600
601 static int pg_release (struct inode *inode, struct file *file)
602 {
603 int unit = DEVICE_NR(inode->i_rdev);
604
605 if ((unit >= PG_UNITS) || (PG.access <= 0))
606 return -EINVAL;
607
608 lock_kernel();
609 PG.access--;
610
611 kfree(PG.bufptr);
612 PG.bufptr = NULL;
613 unlock_kernel();
614
615 return 0;
616
617 }
618
619 static ssize_t pg_write(struct file * filp, const char * buf,
620 size_t count, loff_t *ppos)
621
622 { struct inode *ino = filp->f_dentry->d_inode;
623 int unit = DEVICE_NR(ino->i_rdev);
624 struct pg_write_hdr hdr;
625 int hs = sizeof(hdr);
626
627 if (PG.busy) return -EBUSY;
628 if (count < hs) return -EINVAL;
629
630 copy_from_user((char *)&hdr,buf,hs);
631
632 if (hdr.magic != PG_MAGIC) return -EINVAL;
633 if (hdr.dlen > PG_MAX_DATA) return -EINVAL;
634 if ((count - hs) > PG_MAX_DATA) return -EINVAL;
635
636 if (hdr.func == PG_RESET) {
637 if (count != hs) return -EINVAL;
638 if (pg_reset(unit)) return -EIO;
639 return count;
640 }
641
642 if (hdr.func != PG_COMMAND) return -EINVAL;
643
644 PG.start = jiffies;
645 PG.timeout = hdr.timeout*HZ + HZ/2 + jiffies;
646
647 if (pg_command(unit,hdr.packet,hdr.dlen,jiffies+PG_TMO)) {
648 if (PG.status & 0x10) return -ETIME;
649 return -EIO;
650 }
651
652 PG.busy = 1;
653
654 copy_from_user(PG.bufptr,buf+hs,count-hs);
655
656 return count;
657 }
658
659 static ssize_t pg_read(struct file * filp, char * buf,
660 size_t count, loff_t *ppos)
661
662 { struct inode *ino = filp->f_dentry->d_inode;
663 int unit = DEVICE_NR(ino->i_rdev);
664 struct pg_read_hdr hdr;
665 int hs = sizeof(hdr);
666 int copy;
667
668 if (!PG.busy) return -EINVAL;
669 if (count < hs) return -EINVAL;
670
671 PG.busy = 0;
672
673 if (pg_completion(unit,PG.bufptr,PG.timeout))
674 if (PG.status & 0x10) return -ETIME;
675
676 hdr.magic = PG_MAGIC;
677 hdr.dlen = PG.dlen;
678 copy = 0;
679
680 if (hdr.dlen < 0) {
681 hdr.dlen = -1 * hdr.dlen;
682 copy = hdr.dlen;
683 if (copy > (count - hs)) copy = count - hs;
684 }
685
686 hdr.duration = (jiffies - PG.start + HZ/2) / HZ;
687 hdr.scsi = PG.status & 0x0f;
688
689 copy_to_user(buf,(char *)&hdr,hs);
690 if (copy > 0) copy_to_user(buf+hs,PG.bufptr,copy);
691
692 return copy+hs;
693 }
694
695 /* end of pg.c */
696
697