1/*
2        pd.c    (c) 1997-8  Grant R. Guenther <grant@torque.net>
3                            Under the terms of the GNU General Public License.
4
5        This is the high-level driver for parallel port IDE hard
6        drives based on chips supported by the paride module.
7
8	By default, the driver will autoprobe for a single parallel
9	port IDE drive, but if their individual parameters are
10        specified, the driver can handle up to 4 drives.
11
12        The behaviour of the pd driver can be altered by setting
13        some parameters from the insmod command line.  The following
14        parameters are adjustable:
15
16	    drive0  	These four arguments can be arrays of
17	    drive1	1-8 integers as follows:
18	    drive2
19	    drive3	<prt>,<pro>,<uni>,<mod>,<geo>,<sby>,<dly>,<slv>
20
21			Where,
22
23		<prt>	is the base of the parallel port address for
24			the corresponding drive.  (required)
25
26		<pro>   is the protocol number for the adapter that
27			supports this drive.  These numbers are
28                        logged by 'paride' when the protocol modules
29			are initialised.  (0 if not given)
30
31		<uni>   for those adapters that support chained
32			devices, this is the unit selector for the
33		        chain of devices on the given port.  It should
34			be zero for devices that don't support chaining.
35			(0 if not given)
36
37		<mod>   this can be -1 to choose the best mode, or one
38		        of the mode numbers supported by the adapter.
39			(-1 if not given)
40
41		<geo>   this defaults to 0 to indicate that the driver
42			should use the CHS geometry provided by the drive
43			itself.  If set to 1, the driver will provide
44			a logical geometry with 64 heads and 32 sectors
45			per track, to be consistent with most SCSI
46		        drivers.  (0 if not given)
47
48		<sby>   set this to zero to disable the power saving
49			standby mode, if needed.  (1 if not given)
50
51		<dly>   some parallel ports require the driver to
52			go more slowly.  -1 sets a default value that
53			should work with the chosen protocol.  Otherwise,
54			set this to a small integer, the larger it is
55			the slower the port i/o.  In some cases, setting
56			this to zero will speed up the device. (default -1)
57
58		<slv>   IDE disks can be jumpered to master or slave.
59                        Set this to 0 to choose the master drive, 1 to
60                        choose the slave, -1 (the default) to choose the
61                        first drive found.
62
63
64            major       You may use this parameter to overide the
65                        default major number (45) that this driver
66                        will use.  Be sure to change the device
67                        name as well.
68
69            name        This parameter is a character string that
70                        contains the name the kernel will use for this
71                        device (in /proc output, for instance).
72			(default "pd")
73
74	    cluster	The driver will attempt to aggregate requests
75			for adjacent blocks into larger multi-block
76			clusters.  The maximum cluster size (in 512
77			byte sectors) is set with this parameter.
78			(default 64)
79
80	    verbose	This parameter controls the amount of logging
81			that the driver will do.  Set it to 0 for
82			normal operation, 1 to see autoprobe progress
83			messages, or 2 to see additional debugging
84			output.  (default 0)
85
86            nice        This parameter controls the driver's use of
87                        idle CPU time, at the expense of some speed.
88
89        If this driver is built into the kernel, you can use kernel
90        the following command line parameters, with the same values
91        as the corresponding module parameters listed above:
92
93            pd.drive0
94            pd.drive1
95            pd.drive2
96            pd.drive3
97            pd.cluster
98            pd.nice
99
100        In addition, you can use the parameter pd.disable to disable
101        the driver entirely.
102
103*/
104
105/* Changes:
106
107	1.01	GRG 1997.01.24	Restored pd_reset()
108				Added eject ioctl
109	1.02    GRG 1998.05.06  SMP spinlock changes,
110				Added slave support
111	1.03    GRG 1998.06.16  Eliminate an Ugh.
112	1.04	GRG 1998.08.15  Extra debugging, use HZ in loop timing
113	1.05    GRG 1998.09.24  Added jumbo support
114
115*/
116
117#define PD_VERSION      "1.05"
118#define PD_MAJOR	45
119#define PD_NAME		"pd"
120#define PD_UNITS	4
121
122/* Here are things one can override from the insmod command.
123   Most are autoprobed by paride unless set here.  Verbose is off
124   by default.
125
126*/
127#include <linux/types.h>
128
129static bool verbose = 0;
130static int major = PD_MAJOR;
131static char *name = PD_NAME;
132static int cluster = 64;
133static int nice = 0;
134static int disable = 0;
135
136static int drive0[8] = { 0, 0, 0, -1, 0, 1, -1, -1 };
137static int drive1[8] = { 0, 0, 0, -1, 0, 1, -1, -1 };
138static int drive2[8] = { 0, 0, 0, -1, 0, 1, -1, -1 };
139static int drive3[8] = { 0, 0, 0, -1, 0, 1, -1, -1 };
140
141static int (*drives[4])[8] = {&drive0, &drive1, &drive2, &drive3};
142
143enum {D_PRT, D_PRO, D_UNI, D_MOD, D_GEO, D_SBY, D_DLY, D_SLV};
144
145/* end of parameters */
146
147#include <linux/init.h>
148#include <linux/module.h>
149#include <linux/gfp.h>
150#include <linux/fs.h>
151#include <linux/delay.h>
152#include <linux/hdreg.h>
153#include <linux/cdrom.h>	/* for the eject ioctl */
154#include <linux/blkdev.h>
155#include <linux/blkpg.h>
156#include <linux/kernel.h>
157#include <linux/mutex.h>
158#include <asm/uaccess.h>
159#include <linux/workqueue.h>
160
161static DEFINE_MUTEX(pd_mutex);
162static DEFINE_SPINLOCK(pd_lock);
163
164module_param(verbose, bool, 0);
165module_param(major, int, 0);
166module_param(name, charp, 0);
167module_param(cluster, int, 0);
168module_param(nice, int, 0);
169module_param_array(drive0, int, NULL, 0);
170module_param_array(drive1, int, NULL, 0);
171module_param_array(drive2, int, NULL, 0);
172module_param_array(drive3, int, NULL, 0);
173
174#include "paride.h"
175
176#define PD_BITS    4
177
178/* numbers for "SCSI" geometry */
179
180#define PD_LOG_HEADS    64
181#define PD_LOG_SECTS    32
182
183#define PD_ID_OFF       54
184#define PD_ID_LEN       14
185
186#define PD_MAX_RETRIES  5
187#define PD_TMO          800	/* interrupt timeout in jiffies */
188#define PD_SPIN_DEL     50	/* spin delay in micro-seconds  */
189
190#define PD_SPIN         (1000000*PD_TMO)/(HZ*PD_SPIN_DEL)
191
192#define STAT_ERR        0x00001
193#define STAT_INDEX      0x00002
194#define STAT_ECC        0x00004
195#define STAT_DRQ        0x00008
196#define STAT_SEEK       0x00010
197#define STAT_WRERR      0x00020
198#define STAT_READY      0x00040
199#define STAT_BUSY       0x00080
200
201#define ERR_AMNF        0x00100
202#define ERR_TK0NF       0x00200
203#define ERR_ABRT        0x00400
204#define ERR_MCR         0x00800
205#define ERR_IDNF        0x01000
206#define ERR_MC          0x02000
207#define ERR_UNC         0x04000
208#define ERR_TMO         0x10000
209
210#define IDE_READ        	0x20
211#define IDE_WRITE       	0x30
212#define IDE_READ_VRFY		0x40
213#define IDE_INIT_DEV_PARMS	0x91
214#define IDE_STANDBY     	0x96
215#define IDE_ACKCHANGE   	0xdb
216#define IDE_DOORLOCK    	0xde
217#define IDE_DOORUNLOCK  	0xdf
218#define IDE_IDENTIFY    	0xec
219#define IDE_EJECT		0xed
220
221#define PD_NAMELEN	8
222
223struct pd_unit {
224	struct pi_adapter pia;	/* interface to paride layer */
225	struct pi_adapter *pi;
226	int access;		/* count of active opens ... */
227	int capacity;		/* Size of this volume in sectors */
228	int heads;		/* physical geometry */
229	int sectors;
230	int cylinders;
231	int can_lba;
232	int drive;		/* master=0 slave=1 */
233	int changed;		/* Have we seen a disk change ? */
234	int removable;		/* removable media device  ?  */
235	int standby;
236	int alt_geom;
237	char name[PD_NAMELEN];	/* pda, pdb, etc ... */
238	struct gendisk *gd;
239};
240
241static struct pd_unit pd[PD_UNITS];
242
243static char pd_scratch[512];	/* scratch block buffer */
244
245static char *pd_errs[17] = { "ERR", "INDEX", "ECC", "DRQ", "SEEK", "WRERR",
246	"READY", "BUSY", "AMNF", "TK0NF", "ABRT", "MCR",
247	"IDNF", "MC", "UNC", "???", "TMO"
248};
249
250static inline int status_reg(struct pd_unit *disk)
251{
252	return pi_read_regr(disk->pi, 1, 6);
253}
254
255static inline int read_reg(struct pd_unit *disk, int reg)
256{
257	return pi_read_regr(disk->pi, 0, reg);
258}
259
260static inline void write_status(struct pd_unit *disk, int val)
261{
262	pi_write_regr(disk->pi, 1, 6, val);
263}
264
265static inline void write_reg(struct pd_unit *disk, int reg, int val)
266{
267	pi_write_regr(disk->pi, 0, reg, val);
268}
269
270static inline u8 DRIVE(struct pd_unit *disk)
271{
272	return 0xa0+0x10*disk->drive;
273}
274
275/*  ide command interface */
276
277static void pd_print_error(struct pd_unit *disk, char *msg, int status)
278{
279	int i;
280
281	printk("%s: %s: status = 0x%x =", disk->name, msg, status);
282	for (i = 0; i < ARRAY_SIZE(pd_errs); i++)
283		if (status & (1 << i))
284			printk(" %s", pd_errs[i]);
285	printk("\n");
286}
287
288static void pd_reset(struct pd_unit *disk)
289{				/* called only for MASTER drive */
290	write_status(disk, 4);
291	udelay(50);
292	write_status(disk, 0);
293	udelay(250);
294}
295
296#define DBMSG(msg)	((verbose>1)?(msg):NULL)
297
298static int pd_wait_for(struct pd_unit *disk, int w, char *msg)
299{				/* polled wait */
300	int k, r, e;
301
302	k = 0;
303	while (k < PD_SPIN) {
304		r = status_reg(disk);
305		k++;
306		if (((r & w) == w) && !(r & STAT_BUSY))
307			break;
308		udelay(PD_SPIN_DEL);
309	}
310	e = (read_reg(disk, 1) << 8) + read_reg(disk, 7);
311	if (k >= PD_SPIN)
312		e |= ERR_TMO;
313	if ((e & (STAT_ERR | ERR_TMO)) && (msg != NULL))
314		pd_print_error(disk, msg, e);
315	return e;
316}
317
318static void pd_send_command(struct pd_unit *disk, int n, int s, int h, int c0, int c1, int func)
319{
320	write_reg(disk, 6, DRIVE(disk) + h);
321	write_reg(disk, 1, 0);		/* the IDE task file */
322	write_reg(disk, 2, n);
323	write_reg(disk, 3, s);
324	write_reg(disk, 4, c0);
325	write_reg(disk, 5, c1);
326	write_reg(disk, 7, func);
327
328	udelay(1);
329}
330
331static void pd_ide_command(struct pd_unit *disk, int func, int block, int count)
332{
333	int c1, c0, h, s;
334
335	if (disk->can_lba) {
336		s = block & 255;
337		c0 = (block >>= 8) & 255;
338		c1 = (block >>= 8) & 255;
339		h = ((block >>= 8) & 15) + 0x40;
340	} else {
341		s = (block % disk->sectors) + 1;
342		h = (block /= disk->sectors) % disk->heads;
343		c0 = (block /= disk->heads) % 256;
344		c1 = (block >>= 8);
345	}
346	pd_send_command(disk, count, s, h, c0, c1, func);
347}
348
349/* The i/o request engine */
350
351enum action {Fail = 0, Ok = 1, Hold, Wait};
352
353static struct request *pd_req;	/* current request */
354static enum action (*phase)(void);
355
356static void run_fsm(void);
357
358static void ps_tq_int(struct work_struct *work);
359
360static DECLARE_DELAYED_WORK(fsm_tq, ps_tq_int);
361
362static void schedule_fsm(void)
363{
364	if (!nice)
365		schedule_delayed_work(&fsm_tq, 0);
366	else
367		schedule_delayed_work(&fsm_tq, nice-1);
368}
369
370static void ps_tq_int(struct work_struct *work)
371{
372	run_fsm();
373}
374
375static enum action do_pd_io_start(void);
376static enum action pd_special(void);
377static enum action do_pd_read_start(void);
378static enum action do_pd_write_start(void);
379static enum action do_pd_read_drq(void);
380static enum action do_pd_write_done(void);
381
382static struct request_queue *pd_queue;
383static int pd_claimed;
384
385static struct pd_unit *pd_current; /* current request's drive */
386static PIA *pi_current; /* current request's PIA */
387
388static void run_fsm(void)
389{
390	while (1) {
391		enum action res;
392		unsigned long saved_flags;
393		int stop = 0;
394
395		if (!phase) {
396			pd_current = pd_req->rq_disk->private_data;
397			pi_current = pd_current->pi;
398			phase = do_pd_io_start;
399		}
400
401		switch (pd_claimed) {
402			case 0:
403				pd_claimed = 1;
404				if (!pi_schedule_claimed(pi_current, run_fsm))
405					return;
406			case 1:
407				pd_claimed = 2;
408				pi_current->proto->connect(pi_current);
409		}
410
411		switch(res = phase()) {
412			case Ok: case Fail:
413				pi_disconnect(pi_current);
414				pd_claimed = 0;
415				phase = NULL;
416				spin_lock_irqsave(&pd_lock, saved_flags);
417				if (!__blk_end_request_cur(pd_req,
418						res == Ok ? 0 : -EIO)) {
419					pd_req = blk_fetch_request(pd_queue);
420					if (!pd_req)
421						stop = 1;
422				}
423				spin_unlock_irqrestore(&pd_lock, saved_flags);
424				if (stop)
425					return;
426			case Hold:
427				schedule_fsm();
428				return;
429			case Wait:
430				pi_disconnect(pi_current);
431				pd_claimed = 0;
432		}
433	}
434}
435
436static int pd_retries = 0;	/* i/o error retry count */
437static int pd_block;		/* address of next requested block */
438static int pd_count;		/* number of blocks still to do */
439static int pd_run;		/* sectors in current cluster */
440static int pd_cmd;		/* current command READ/WRITE */
441static char *pd_buf;		/* buffer for request in progress */
442
443static enum action do_pd_io_start(void)
444{
445	if (pd_req->cmd_type == REQ_TYPE_SPECIAL) {
446		phase = pd_special;
447		return pd_special();
448	}
449
450	pd_cmd = rq_data_dir(pd_req);
451	if (pd_cmd == READ || pd_cmd == WRITE) {
452		pd_block = blk_rq_pos(pd_req);
453		pd_count = blk_rq_cur_sectors(pd_req);
454		if (pd_block + pd_count > get_capacity(pd_req->rq_disk))
455			return Fail;
456		pd_run = blk_rq_sectors(pd_req);
457		pd_buf = pd_req->buffer;
458		pd_retries = 0;
459		if (pd_cmd == READ)
460			return do_pd_read_start();
461		else
462			return do_pd_write_start();
463	}
464	return Fail;
465}
466
467static enum action pd_special(void)
468{
469	enum action (*func)(struct pd_unit *) = pd_req->special;
470	return func(pd_current);
471}
472
473static int pd_next_buf(void)
474{
475	unsigned long saved_flags;
476
477	pd_count--;
478	pd_run--;
479	pd_buf += 512;
480	pd_block++;
481	if (!pd_run)
482		return 1;
483	if (pd_count)
484		return 0;
485	spin_lock_irqsave(&pd_lock, saved_flags);
486	__blk_end_request_cur(pd_req, 0);
487	pd_count = blk_rq_cur_sectors(pd_req);
488	pd_buf = pd_req->buffer;
489	spin_unlock_irqrestore(&pd_lock, saved_flags);
490	return 0;
491}
492
493static unsigned long pd_timeout;
494
495static enum action do_pd_read_start(void)
496{
497	if (pd_wait_for(pd_current, STAT_READY, "do_pd_read") & STAT_ERR) {
498		if (pd_retries < PD_MAX_RETRIES) {
499			pd_retries++;
500			return Wait;
501		}
502		return Fail;
503	}
504	pd_ide_command(pd_current, IDE_READ, pd_block, pd_run);
505	phase = do_pd_read_drq;
506	pd_timeout = jiffies + PD_TMO;
507	return Hold;
508}
509
510static enum action do_pd_write_start(void)
511{
512	if (pd_wait_for(pd_current, STAT_READY, "do_pd_write") & STAT_ERR) {
513		if (pd_retries < PD_MAX_RETRIES) {
514			pd_retries++;
515			return Wait;
516		}
517		return Fail;
518	}
519	pd_ide_command(pd_current, IDE_WRITE, pd_block, pd_run);
520	while (1) {
521		if (pd_wait_for(pd_current, STAT_DRQ, "do_pd_write_drq") & STAT_ERR) {
522			if (pd_retries < PD_MAX_RETRIES) {
523				pd_retries++;
524				return Wait;
525			}
526			return Fail;
527		}
528		pi_write_block(pd_current->pi, pd_buf, 512);
529		if (pd_next_buf())
530			break;
531	}
532	phase = do_pd_write_done;
533	pd_timeout = jiffies + PD_TMO;
534	return Hold;
535}
536
537static inline int pd_ready(void)
538{
539	return !(status_reg(pd_current) & STAT_BUSY);
540}
541
542static enum action do_pd_read_drq(void)
543{
544	if (!pd_ready() && !time_after_eq(jiffies, pd_timeout))
545		return Hold;
546
547	while (1) {
548		if (pd_wait_for(pd_current, STAT_DRQ, "do_pd_read_drq") & STAT_ERR) {
549			if (pd_retries < PD_MAX_RETRIES) {
550				pd_retries++;
551				phase = do_pd_read_start;
552				return Wait;
553			}
554			return Fail;
555		}
556		pi_read_block(pd_current->pi, pd_buf, 512);
557		if (pd_next_buf())
558			break;
559	}
560	return Ok;
561}
562
563static enum action do_pd_write_done(void)
564{
565	if (!pd_ready() && !time_after_eq(jiffies, pd_timeout))
566		return Hold;
567
568	if (pd_wait_for(pd_current, STAT_READY, "do_pd_write_done") & STAT_ERR) {
569		if (pd_retries < PD_MAX_RETRIES) {
570			pd_retries++;
571			phase = do_pd_write_start;
572			return Wait;
573		}
574		return Fail;
575	}
576	return Ok;
577}
578
579/* special io requests */
580
581/* According to the ATA standard, the default CHS geometry should be
582   available following a reset.  Some Western Digital drives come up
583   in a mode where only LBA addresses are accepted until the device
584   parameters are initialised.
585*/
586
587static void pd_init_dev_parms(struct pd_unit *disk)
588{
589	pd_wait_for(disk, 0, DBMSG("before init_dev_parms"));
590	pd_send_command(disk, disk->sectors, 0, disk->heads - 1, 0, 0,
591			IDE_INIT_DEV_PARMS);
592	udelay(300);
593	pd_wait_for(disk, 0, "Initialise device parameters");
594}
595
596static enum action pd_door_lock(struct pd_unit *disk)
597{
598	if (!(pd_wait_for(disk, STAT_READY, "Lock") & STAT_ERR)) {
599		pd_send_command(disk, 1, 0, 0, 0, 0, IDE_DOORLOCK);
600		pd_wait_for(disk, STAT_READY, "Lock done");
601	}
602	return Ok;
603}
604
605static enum action pd_door_unlock(struct pd_unit *disk)
606{
607	if (!(pd_wait_for(disk, STAT_READY, "Lock") & STAT_ERR)) {
608		pd_send_command(disk, 1, 0, 0, 0, 0, IDE_DOORUNLOCK);
609		pd_wait_for(disk, STAT_READY, "Lock done");
610	}
611	return Ok;
612}
613
614static enum action pd_eject(struct pd_unit *disk)
615{
616	pd_wait_for(disk, 0, DBMSG("before unlock on eject"));
617	pd_send_command(disk, 1, 0, 0, 0, 0, IDE_DOORUNLOCK);
618	pd_wait_for(disk, 0, DBMSG("after unlock on eject"));
619	pd_wait_for(disk, 0, DBMSG("before eject"));
620	pd_send_command(disk, 0, 0, 0, 0, 0, IDE_EJECT);
621	pd_wait_for(disk, 0, DBMSG("after eject"));
622	return Ok;
623}
624
625static enum action pd_media_check(struct pd_unit *disk)
626{
627	int r = pd_wait_for(disk, STAT_READY, DBMSG("before media_check"));
628	if (!(r & STAT_ERR)) {
629		pd_send_command(disk, 1, 1, 0, 0, 0, IDE_READ_VRFY);
630		r = pd_wait_for(disk, STAT_READY, DBMSG("RDY after READ_VRFY"));
631	} else
632		disk->changed = 1;	/* say changed if other error */
633	if (r & ERR_MC) {
634		disk->changed = 1;
635		pd_send_command(disk, 1, 0, 0, 0, 0, IDE_ACKCHANGE);
636		pd_wait_for(disk, STAT_READY, DBMSG("RDY after ACKCHANGE"));
637		pd_send_command(disk, 1, 1, 0, 0, 0, IDE_READ_VRFY);
638		r = pd_wait_for(disk, STAT_READY, DBMSG("RDY after VRFY"));
639	}
640	return Ok;
641}
642
643static void pd_standby_off(struct pd_unit *disk)
644{
645	pd_wait_for(disk, 0, DBMSG("before STANDBY"));
646	pd_send_command(disk, 0, 0, 0, 0, 0, IDE_STANDBY);
647	pd_wait_for(disk, 0, DBMSG("after STANDBY"));
648}
649
650static enum action pd_identify(struct pd_unit *disk)
651{
652	int j;
653	char id[PD_ID_LEN + 1];
654
655/* WARNING:  here there may be dragons.  reset() applies to both drives,
656   but we call it only on probing the MASTER. This should allow most
657   common configurations to work, but be warned that a reset can clear
658   settings on the SLAVE drive.
659*/
660
661	if (disk->drive == 0)
662		pd_reset(disk);
663
664	write_reg(disk, 6, DRIVE(disk));
665	pd_wait_for(disk, 0, DBMSG("before IDENT"));
666	pd_send_command(disk, 1, 0, 0, 0, 0, IDE_IDENTIFY);
667
668	if (pd_wait_for(disk, STAT_DRQ, DBMSG("IDENT DRQ")) & STAT_ERR)
669		return Fail;
670	pi_read_block(disk->pi, pd_scratch, 512);
671	disk->can_lba = pd_scratch[99] & 2;
672	disk->sectors = le16_to_cpu(*(__le16 *) (pd_scratch + 12));
673	disk->heads = le16_to_cpu(*(__le16 *) (pd_scratch + 6));
674	disk->cylinders = le16_to_cpu(*(__le16 *) (pd_scratch + 2));
675	if (disk->can_lba)
676		disk->capacity = le32_to_cpu(*(__le32 *) (pd_scratch + 120));
677	else
678		disk->capacity = disk->sectors * disk->heads * disk->cylinders;
679
680	for (j = 0; j < PD_ID_LEN; j++)
681		id[j ^ 1] = pd_scratch[j + PD_ID_OFF];
682	j = PD_ID_LEN - 1;
683	while ((j >= 0) && (id[j] <= 0x20))
684		j--;
685	j++;
686	id[j] = 0;
687
688	disk->removable = pd_scratch[0] & 0x80;
689
690	printk("%s: %s, %s, %d blocks [%dM], (%d/%d/%d), %s media\n",
691	       disk->name, id,
692	       disk->drive ? "slave" : "master",
693	       disk->capacity, disk->capacity / 2048,
694	       disk->cylinders, disk->heads, disk->sectors,
695	       disk->removable ? "removable" : "fixed");
696
697	if (disk->capacity)
698		pd_init_dev_parms(disk);
699	if (!disk->standby)
700		pd_standby_off(disk);
701
702	return Ok;
703}
704
705/* end of io request engine */
706
707static void do_pd_request(struct request_queue * q)
708{
709	if (pd_req)
710		return;
711	pd_req = blk_fetch_request(q);
712	if (!pd_req)
713		return;
714
715	schedule_fsm();
716}
717
718static int pd_special_command(struct pd_unit *disk,
719		      enum action (*func)(struct pd_unit *disk))
720{
721	struct request *rq;
722	int err = 0;
723
724	rq = blk_get_request(disk->gd->queue, READ, __GFP_WAIT);
725
726	rq->cmd_type = REQ_TYPE_SPECIAL;
727	rq->special = func;
728
729	err = blk_execute_rq(disk->gd->queue, disk->gd, rq, 0);
730
731	blk_put_request(rq);
732	return err;
733}
734
735/* kernel glue structures */
736
737static int pd_open(struct block_device *bdev, fmode_t mode)
738{
739	struct pd_unit *disk = bdev->bd_disk->private_data;
740
741	mutex_lock(&pd_mutex);
742	disk->access++;
743
744	if (disk->removable) {
745		pd_special_command(disk, pd_media_check);
746		pd_special_command(disk, pd_door_lock);
747	}
748	mutex_unlock(&pd_mutex);
749	return 0;
750}
751
752static int pd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
753{
754	struct pd_unit *disk = bdev->bd_disk->private_data;
755
756	if (disk->alt_geom) {
757		geo->heads = PD_LOG_HEADS;
758		geo->sectors = PD_LOG_SECTS;
759		geo->cylinders = disk->capacity / (geo->heads * geo->sectors);
760	} else {
761		geo->heads = disk->heads;
762		geo->sectors = disk->sectors;
763		geo->cylinders = disk->cylinders;
764	}
765
766	return 0;
767}
768
769static int pd_ioctl(struct block_device *bdev, fmode_t mode,
770	 unsigned int cmd, unsigned long arg)
771{
772	struct pd_unit *disk = bdev->bd_disk->private_data;
773
774	switch (cmd) {
775	case CDROMEJECT:
776		mutex_lock(&pd_mutex);
777		if (disk->access == 1)
778			pd_special_command(disk, pd_eject);
779		mutex_unlock(&pd_mutex);
780		return 0;
781	default:
782		return -EINVAL;
783	}
784}
785
786static int pd_release(struct gendisk *p, fmode_t mode)
787{
788	struct pd_unit *disk = p->private_data;
789
790	mutex_lock(&pd_mutex);
791	if (!--disk->access && disk->removable)
792		pd_special_command(disk, pd_door_unlock);
793	mutex_unlock(&pd_mutex);
794
795	return 0;
796}
797
798static unsigned int pd_check_events(struct gendisk *p, unsigned int clearing)
799{
800	struct pd_unit *disk = p->private_data;
801	int r;
802	if (!disk->removable)
803		return 0;
804	pd_special_command(disk, pd_media_check);
805	r = disk->changed;
806	disk->changed = 0;
807	return r ? DISK_EVENT_MEDIA_CHANGE : 0;
808}
809
810static int pd_revalidate(struct gendisk *p)
811{
812	struct pd_unit *disk = p->private_data;
813	if (pd_special_command(disk, pd_identify) == 0)
814		set_capacity(p, disk->capacity);
815	else
816		set_capacity(p, 0);
817	return 0;
818}
819
820static const struct block_device_operations pd_fops = {
821	.owner		= THIS_MODULE,
822	.open		= pd_open,
823	.release	= pd_release,
824	.ioctl		= pd_ioctl,
825	.getgeo		= pd_getgeo,
826	.check_events	= pd_check_events,
827	.revalidate_disk= pd_revalidate
828};
829
830/* probing */
831
832static void pd_probe_drive(struct pd_unit *disk)
833{
834	struct gendisk *p = alloc_disk(1 << PD_BITS);
835	if (!p)
836		return;
837	strcpy(p->disk_name, disk->name);
838	p->fops = &pd_fops;
839	p->major = major;
840	p->first_minor = (disk - pd) << PD_BITS;
841	disk->gd = p;
842	p->private_data = disk;
843	p->queue = pd_queue;
844
845	if (disk->drive == -1) {
846		for (disk->drive = 0; disk->drive <= 1; disk->drive++)
847			if (pd_special_command(disk, pd_identify) == 0)
848				return;
849	} else if (pd_special_command(disk, pd_identify) == 0)
850		return;
851	disk->gd = NULL;
852	put_disk(p);
853}
854
855static int pd_detect(void)
856{
857	int found = 0, unit, pd_drive_count = 0;
858	struct pd_unit *disk;
859
860	for (unit = 0; unit < PD_UNITS; unit++) {
861		int *parm = *drives[unit];
862		struct pd_unit *disk = pd + unit;
863		disk->pi = &disk->pia;
864		disk->access = 0;
865		disk->changed = 1;
866		disk->capacity = 0;
867		disk->drive = parm[D_SLV];
868		snprintf(disk->name, PD_NAMELEN, "%s%c", name, 'a'+unit);
869		disk->alt_geom = parm[D_GEO];
870		disk->standby = parm[D_SBY];
871		if (parm[D_PRT])
872			pd_drive_count++;
873	}
874
875	if (pd_drive_count == 0) { /* nothing spec'd - so autoprobe for 1 */
876		disk = pd;
877		if (pi_init(disk->pi, 1, -1, -1, -1, -1, -1, pd_scratch,
878			    PI_PD, verbose, disk->name)) {
879			pd_probe_drive(disk);
880			if (!disk->gd)
881				pi_release(disk->pi);
882		}
883
884	} else {
885		for (unit = 0, disk = pd; unit < PD_UNITS; unit++, disk++) {
886			int *parm = *drives[unit];
887			if (!parm[D_PRT])
888				continue;
889			if (pi_init(disk->pi, 0, parm[D_PRT], parm[D_MOD],
890				     parm[D_UNI], parm[D_PRO], parm[D_DLY],
891				     pd_scratch, PI_PD, verbose, disk->name)) {
892				pd_probe_drive(disk);
893				if (!disk->gd)
894					pi_release(disk->pi);
895			}
896		}
897	}
898	for (unit = 0, disk = pd; unit < PD_UNITS; unit++, disk++) {
899		if (disk->gd) {
900			set_capacity(disk->gd, disk->capacity);
901			add_disk(disk->gd);
902			found = 1;
903		}
904	}
905	if (!found)
906		printk("%s: no valid drive found\n", name);
907	return found;
908}
909
910static int __init pd_init(void)
911{
912	if (disable)
913		goto out1;
914
915	pd_queue = blk_init_queue(do_pd_request, &pd_lock);
916	if (!pd_queue)
917		goto out1;
918
919	blk_queue_max_hw_sectors(pd_queue, cluster);
920
921	if (register_blkdev(major, name))
922		goto out2;
923
924	printk("%s: %s version %s, major %d, cluster %d, nice %d\n",
925	       name, name, PD_VERSION, major, cluster, nice);
926	if (!pd_detect())
927		goto out3;
928
929	return 0;
930
931out3:
932	unregister_blkdev(major, name);
933out2:
934	blk_cleanup_queue(pd_queue);
935out1:
936	return -ENODEV;
937}
938
939static void __exit pd_exit(void)
940{
941	struct pd_unit *disk;
942	int unit;
943	unregister_blkdev(major, name);
944	for (unit = 0, disk = pd; unit < PD_UNITS; unit++, disk++) {
945		struct gendisk *p = disk->gd;
946		if (p) {
947			disk->gd = NULL;
948			del_gendisk(p);
949			put_disk(p);
950			pi_release(disk->pi);
951		}
952	}
953	blk_cleanup_queue(pd_queue);
954}
955
956MODULE_LICENSE("GPL");
957module_init(pd_init)
958module_exit(pd_exit)
959