[PATCH] devfs: Remove devfs_mk_cdev() function from the kernel tree
[linux-2.6] / drivers / block / swim_iop.c
1 /*
2  * Driver for the SWIM (Super Woz Integrated Machine) IOP
3  * floppy controller on the Macintosh IIfx and Quadra 900/950
4  *
5  * Written by Joshua M. Thompson (funaho@jurai.org)
6  * based on the SWIM3 driver (c) 1996 by Paul Mackerras.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * as published by the Free Software Foundation; either version
11  * 2 of the License, or (at your option) any later version.
12  *
13  * 1999-06-12 (jmt) - Initial implementation.
14  */
15
16 /*
17  * -------------------
18  * Theory of Operation
19  * -------------------
20  *
21  * Since the SWIM IOP is message-driven we implement a simple request queue
22  * system.  One outstanding request may be queued at any given time (this is
23  * an IOP limitation); only when that request has completed can a new request
24  * be sent.
25  */
26
27 #include <linux/stddef.h>
28 #include <linux/kernel.h>
29 #include <linux/sched.h>
30 #include <linux/timer.h>
31 #include <linux/delay.h>
32 #include <linux/fd.h>
33 #include <linux/ioctl.h>
34 #include <linux/blkdev.h>
35 #include <asm/io.h>
36 #include <asm/uaccess.h>
37 #include <asm/mac_iop.h>
38 #include <asm/swim_iop.h>
39
40 #define DRIVER_VERSION "Version 0.1 (1999-06-12)"
41
42 #define MAX_FLOPPIES    4
43
44 enum swim_state {
45         idle,
46         available,
47         revalidating,
48         transferring,
49         ejecting
50 };
51
52 struct floppy_state {
53         enum swim_state state;
54         int     drive_num;      /* device number */
55         int     secpercyl;      /* disk geometry information */
56         int     secpertrack;
57         int     total_secs;
58         int     write_prot;     /* 1 if write-protected, 0 if not, -1 dunno */
59         int     ref_count;
60         struct timer_list timeout;
61         int     ejected;
62         struct wait_queue *wait;
63         int     wanted;
64         int     timeout_pending;
65 };
66
67 struct swim_iop_req {
68         int     sent;
69         int     complete;
70         __u8    command[32];
71         struct floppy_state *fs;
72         void    (*done)(struct swim_iop_req *);
73 };
74
75 static struct swim_iop_req *current_req;
76 static int floppy_count;
77
78 static struct floppy_state floppy_states[MAX_FLOPPIES];
79 static DEFINE_SPINLOCK(swim_iop_lock);
80
81 #define CURRENT elv_next_request(swim_queue)
82
83 static char *drive_names[7] = {
84         "not installed",        /* DRV_NONE    */
85         "unknown (1)",          /* DRV_UNKNOWN */
86         "a 400K drive",         /* DRV_400K    */
87         "an 800K drive"         /* DRV_800K    */
88         "unknown (4)",          /* ????        */
89         "an FDHD",              /* DRV_FDHD    */
90         "unknown (6)",          /* ????        */
91         "an Apple HD20"         /* DRV_HD20    */
92 };
93
94 int swimiop_init(void);
95 static void swimiop_init_request(struct swim_iop_req *);
96 static int swimiop_send_request(struct swim_iop_req *);
97 static void swimiop_receive(struct iop_msg *, struct pt_regs *);
98 static void swimiop_status_update(int, struct swim_drvstatus *);
99 static int swimiop_eject(struct floppy_state *fs);
100
101 static int floppy_ioctl(struct inode *inode, struct file *filp,
102                         unsigned int cmd, unsigned long param);
103 static int floppy_open(struct inode *inode, struct file *filp);
104 static int floppy_release(struct inode *inode, struct file *filp);
105 static int floppy_check_change(struct gendisk *disk);
106 static int floppy_revalidate(struct gendisk *disk);
107 static int grab_drive(struct floppy_state *fs, enum swim_state state,
108                       int interruptible);
109 static void release_drive(struct floppy_state *fs);
110 static void set_timeout(struct floppy_state *fs, int nticks,
111                         void (*proc)(unsigned long));
112 static void fd_request_timeout(unsigned long);
113 static void do_fd_request(request_queue_t * q);
114 static void start_request(struct floppy_state *fs);
115
116 static struct block_device_operations floppy_fops = {
117         .open           = floppy_open,
118         .release        = floppy_release,
119         .ioctl          = floppy_ioctl,
120         .media_changed  = floppy_check_change,
121         .revalidate_disk= floppy_revalidate,
122 };
123
124 static struct request_queue *swim_queue;
125 /*
126  * SWIM IOP initialization
127  */
128
129 int swimiop_init(void)
130 {
131         volatile struct swim_iop_req req;
132         struct swimcmd_status *cmd = (struct swimcmd_status *) &req.command[0];
133         struct swim_drvstatus *ds = &cmd->status;
134         struct floppy_state *fs;
135         int i;
136
137         current_req = NULL;
138         floppy_count = 0;
139
140         if (!iop_ism_present)
141                 return -ENODEV;
142
143         if (register_blkdev(FLOPPY_MAJOR, "fd"))
144                 return -EBUSY;
145
146         swim_queue = blk_init_queue(do_fd_request, &swim_iop_lock);
147         if (!swim_queue) {
148                 unregister_blkdev(FLOPPY_MAJOR, "fd");
149                 return -ENOMEM;
150         }
151
152         printk("SWIM-IOP: %s by Joshua M. Thompson (funaho@jurai.org)\n",
153                 DRIVER_VERSION);
154
155         if (iop_listen(SWIM_IOP, SWIM_CHAN, swimiop_receive, "SWIM") != 0) {
156                 printk(KERN_ERR "SWIM-IOP: IOP channel already in use; can't initialize.\n");
157                 unregister_blkdev(FLOPPY_MAJOR, "fd");
158                 blk_cleanup_queue(swim_queue);
159                 return -EBUSY;
160         }
161
162         printk(KERN_ERR "SWIM_IOP: probing for installed drives.\n");
163
164         for (i = 0 ; i < MAX_FLOPPIES ; i++) {
165                 memset(&floppy_states[i], 0, sizeof(struct floppy_state));
166                 fs = &floppy_states[floppy_count];
167
168                 swimiop_init_request(&req);
169                 cmd->code = CMD_STATUS;
170                 cmd->drive_num = i + 1;
171                 if (swimiop_send_request(&req) != 0) continue;
172                 while (!req.complete);
173                 if (cmd->error != 0) {
174                         printk(KERN_ERR "SWIM-IOP: probe on drive %d returned error %d\n", i, (uint) cmd->error);
175                         continue;
176                 }
177                 if (ds->installed != 0x01) continue;
178                 printk("SWIM-IOP: drive %d is %s (%s, %s, %s, %s)\n", i,
179                         drive_names[ds->info.type],
180                         ds->info.external? "ext" : "int",
181                         ds->info.scsi? "scsi" : "floppy",
182                         ds->info.fixed? "fixed" : "removable",
183                         ds->info.secondary? "secondary" : "primary");
184                 swimiop_status_update(floppy_count, ds);
185                 fs->state = idle;
186
187                 init_timer(&fs->timeout);
188                 floppy_count++;
189         }
190         printk("SWIM-IOP: detected %d installed drives.\n", floppy_count);
191
192         for (i = 0; i < floppy_count; i++) {
193                 struct gendisk *disk = alloc_disk(1);
194                 if (!disk)
195                         continue;
196                 disk->major = FLOPPY_MAJOR;
197                 disk->first_minor = i;
198                 disk->fops = &floppy_fops;
199                 sprintf(disk->disk_name, "fd%d", i);
200                 disk->private_data = &floppy_states[i];
201                 disk->queue = swim_queue;
202                 set_capacity(disk, 2880 * 2);
203                 add_disk(disk);
204         }
205
206         return 0;
207 }
208
209 static void swimiop_init_request(struct swim_iop_req *req)
210 {
211         req->sent = 0;
212         req->complete = 0;
213         req->done = NULL;
214 }
215
216 static int swimiop_send_request(struct swim_iop_req *req)
217 {
218         unsigned long flags;
219         int err;
220
221         /* It's doubtful an interrupt routine would try to send */
222         /* a SWIM request, but I'd rather play it safe here.    */
223
224         local_irq_save(flags);
225
226         if (current_req != NULL) {
227                 local_irq_restore(flags);
228                 return -ENOMEM;
229         }
230
231         current_req = req;
232
233         /* Interrupts should be back on for iop_send_message() */
234
235         local_irq_restore(flags);
236
237         err = iop_send_message(SWIM_IOP, SWIM_CHAN, (void *) req,
238                                 sizeof(req->command), (__u8 *) &req->command[0],
239                                 swimiop_receive);
240
241         /* No race condition here; we own current_req at this point */
242
243         if (err) {
244                 current_req = NULL;
245         } else {
246                 req->sent = 1;
247         }
248         return err;
249 }
250
251 /*
252  * Receive a SWIM message from the IOP.
253  *
254  * This will be called in two cases:
255  *
256  * 1. A message has been successfully sent to the IOP.
257  * 2. An unsolicited message was received from the IOP.
258  */
259
260 void swimiop_receive(struct iop_msg *msg, struct pt_regs *regs)
261 {
262         struct swim_iop_req *req;
263         struct swimmsg_status *sm;
264         struct swim_drvstatus *ds;
265
266         req = current_req;
267
268         switch(msg->status) {
269                 case IOP_MSGSTATUS_COMPLETE:
270                         memcpy(&req->command[0], &msg->reply[0], sizeof(req->command));
271                         req->complete = 1;
272                         if (req->done) (*req->done)(req);
273                         current_req = NULL;
274                         break;
275                 case IOP_MSGSTATUS_UNSOL:
276                         sm = (struct swimmsg_status *) &msg->message[0];
277                         ds = &sm->status;
278                         swimiop_status_update(sm->drive_num, ds);
279                         iop_complete_message(msg);
280                         break;
281         }
282 }
283
284 static void swimiop_status_update(int drive_num, struct swim_drvstatus *ds)
285 {
286         struct floppy_state *fs = &floppy_states[drive_num];
287
288         fs->write_prot = (ds->write_prot == 0x80);
289         if ((ds->disk_in_drive != 0x01) && (ds->disk_in_drive != 0x02)) {
290                 fs->ejected = 1;
291         } else {
292                 fs->ejected = 0;
293         }
294         switch(ds->info.type) {
295                 case DRV_400K:
296                         fs->secpercyl = 10;
297                         fs->secpertrack = 10;
298                         fs->total_secs = 800;
299                         break;
300                 case DRV_800K:
301                         fs->secpercyl = 20;
302                         fs->secpertrack = 10;
303                         fs->total_secs = 1600;
304                         break;
305                 case DRV_FDHD:
306                         fs->secpercyl = 36;
307                         fs->secpertrack = 18;
308                         fs->total_secs = 2880;
309                         break;
310                 default:
311                         fs->secpercyl = 0;
312                         fs->secpertrack = 0;
313                         fs->total_secs = 0;
314                         break;
315         }
316 }
317
318 static int swimiop_eject(struct floppy_state *fs)
319 {
320         int err, n;
321         struct swim_iop_req req;
322         struct swimcmd_eject *cmd = (struct swimcmd_eject *) &req.command[0];
323
324         err = grab_drive(fs, ejecting, 1);
325         if (err) return err;
326
327         swimiop_init_request(&req);
328         cmd->code = CMD_EJECT;
329         cmd->drive_num = fs->drive_num;
330         err = swimiop_send_request(&req);
331         if (err) {
332                 release_drive(fs);
333                 return err;
334         }
335         for (n = 2*HZ; n > 0; --n) {
336                 if (req.complete) break;
337                 if (signal_pending(current)) {
338                         err = -EINTR;
339                         break;
340                 }
341                 schedule_timeout_interruptible(1);
342         }
343         release_drive(fs);
344         return cmd->error;
345 }
346
347 static struct floppy_struct floppy_type =
348         { 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };    /*  7 1.44MB 3.5"   */
349
350 static int floppy_ioctl(struct inode *inode, struct file *filp,
351                         unsigned int cmd, unsigned long param)
352 {
353         struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
354         int err;
355
356         if ((cmd & 0x80) && !capable(CAP_SYS_ADMIN))
357                 return -EPERM;
358
359         switch (cmd) {
360         case FDEJECT:
361                 if (fs->ref_count != 1)
362                         return -EBUSY;
363                 err = swimiop_eject(fs);
364                 return err;
365         case FDGETPRM:
366                 if (copy_to_user((void *) param, (void *) &floppy_type,
367                                  sizeof(struct floppy_struct)))
368                         return -EFAULT;
369                 return 0;
370         }
371         return -ENOTTY;
372 }
373
374 static int floppy_open(struct inode *inode, struct file *filp)
375 {
376         struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
377
378         if (fs->ref_count == -1 || filp->f_flags & O_EXCL)
379                 return -EBUSY;
380
381         if ((filp->f_flags & O_NDELAY) == 0 && (filp->f_mode & 3)) {
382                 check_disk_change(inode->i_bdev);
383                 if (fs->ejected)
384                         return -ENXIO;
385         }
386
387         if ((filp->f_mode & 2) && fs->write_prot)
388                 return -EROFS;
389
390         if (filp->f_flags & O_EXCL)
391                 fs->ref_count = -1;
392         else
393                 ++fs->ref_count;
394
395         return 0;
396 }
397
398 static int floppy_release(struct inode *inode, struct file *filp)
399 {
400         struct floppy_state *fs = inode->i_bdev->bd_disk->private_data;
401         if (fs->ref_count > 0)
402                 fs->ref_count--;
403         return 0;
404 }
405
406 static int floppy_check_change(struct gendisk *disk)
407 {
408         struct floppy_state *fs = disk->private_data;
409         return fs->ejected;
410 }
411
412 static int floppy_revalidate(struct gendisk *disk)
413 {
414         struct floppy_state *fs = disk->private_data;
415         grab_drive(fs, revalidating, 0);
416         /* yadda, yadda */
417         release_drive(fs);
418         return 0;
419 }
420
421 static void floppy_off(unsigned int nr)
422 {
423 }
424
425 static int grab_drive(struct floppy_state *fs, enum swim_state state,
426                       int interruptible)
427 {
428         unsigned long flags;
429
430         local_irq_save(flags);
431         if (fs->state != idle) {
432                 ++fs->wanted;
433                 while (fs->state != available) {
434                         if (interruptible && signal_pending(current)) {
435                                 --fs->wanted;
436                                 local_irq_restore(flags);
437                                 return -EINTR;
438                         }
439                         interruptible_sleep_on(&fs->wait);
440                 }
441                 --fs->wanted;
442         }
443         fs->state = state;
444         local_irq_restore(flags);
445         return 0;
446 }
447
448 static void release_drive(struct floppy_state *fs)
449 {
450         unsigned long flags;
451
452         local_irq_save(flags);
453         fs->state = idle;
454         start_request(fs);
455         local_irq_restore(flags);
456 }
457
458 static void set_timeout(struct floppy_state *fs, int nticks,
459                         void (*proc)(unsigned long))
460 {
461         unsigned long flags;
462
463         local_irq_save(flags);
464         if (fs->timeout_pending)
465                 del_timer(&fs->timeout);
466         init_timer(&fs->timeout);
467         fs->timeout.expires = jiffies + nticks;
468         fs->timeout.function = proc;
469         fs->timeout.data = (unsigned long) fs;
470         add_timer(&fs->timeout);
471         fs->timeout_pending = 1;
472         local_irq_restore(flags);
473 }
474
475 static void do_fd_request(request_queue_t * q)
476 {
477         int i;
478
479         for (i = 0 ; i < floppy_count ; i++) {
480                 start_request(&floppy_states[i]);
481         }
482 }
483
484 static void fd_request_complete(struct swim_iop_req *req)
485 {
486         struct floppy_state *fs = req->fs;
487         struct swimcmd_rw *cmd = (struct swimcmd_rw *) &req->command[0];
488
489         del_timer(&fs->timeout);
490         fs->timeout_pending = 0;
491         fs->state = idle;
492         if (cmd->error) {
493                 printk(KERN_ERR "SWIM-IOP: error %d on read/write request.\n", cmd->error);
494                 end_request(CURRENT, 0);
495         } else {
496                 CURRENT->sector += cmd->num_blocks;
497                 CURRENT->current_nr_sectors -= cmd->num_blocks;
498                 if (CURRENT->current_nr_sectors <= 0) {
499                         end_request(CURRENT, 1);
500                         return;
501                 }
502         }
503         start_request(fs);
504 }
505
506 static void fd_request_timeout(unsigned long data)
507 {
508         struct floppy_state *fs = (struct floppy_state *) data;
509
510         fs->timeout_pending = 0;
511         end_request(CURRENT, 0);
512         fs->state = idle;
513 }
514
515 static void start_request(struct floppy_state *fs)
516 {
517         volatile struct swim_iop_req req;
518         struct swimcmd_rw *cmd = (struct swimcmd_rw *) &req.command[0];
519
520         if (fs->state == idle && fs->wanted) {
521                 fs->state = available;
522                 wake_up(&fs->wait);
523                 return;
524         }
525         while (CURRENT && fs->state == idle) {
526                 if (CURRENT->bh && !buffer_locked(CURRENT->bh))
527                         panic("floppy: block not locked");
528 #if 0
529                 printk("do_fd_req: dev=%s cmd=%d sec=%ld nr_sec=%ld buf=%p\n",
530                        CURRENT->rq_disk->disk_name, CURRENT->cmd,
531                        CURRENT->sector, CURRENT->nr_sectors, CURRENT->buffer);
532                 printk("           rq_status=%d errors=%d current_nr_sectors=%ld\n",
533                        CURRENT->rq_status, CURRENT->errors, CURRENT->current_nr_sectors);
534 #endif
535
536                 if (CURRENT->sector < 0 || CURRENT->sector >= fs->total_secs) {
537                         end_request(CURRENT, 0);
538                         continue;
539                 }
540                 if (CURRENT->current_nr_sectors == 0) {
541                         end_request(CURRENT, 1);
542                         continue;
543                 }
544                 if (fs->ejected) {
545                         end_request(CURRENT, 0);
546                         continue;
547                 }
548
549                 swimiop_init_request(&req);
550                 req.fs = fs;
551                 req.done = fd_request_complete;
552
553                 if (CURRENT->cmd == WRITE) {
554                         if (fs->write_prot) {
555                                 end_request(CURRENT, 0);
556                                 continue;
557                         }
558                         cmd->code = CMD_WRITE;
559                 } else {
560                         cmd->code = CMD_READ;
561
562                 }
563                 cmd->drive_num = fs->drive_num;
564                 cmd->buffer = CURRENT->buffer;
565                 cmd->first_block = CURRENT->sector;
566                 cmd->num_blocks = CURRENT->current_nr_sectors;
567
568                 if (swimiop_send_request(&req)) {
569                         end_request(CURRENT, 0);
570                         continue;
571                 }
572
573                 set_timeout(fs, HZ*CURRENT->current_nr_sectors,
574                                 fd_request_timeout);
575
576                 fs->state = transferring;
577         }
578 }