GNU Linux-libre 5.10.219-gnu1
[releases.git] / drivers / ide / ide-atapi.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ATAPI support.
4  */
5
6 #include <linux/kernel.h>
7 #include <linux/cdrom.h>
8 #include <linux/delay.h>
9 #include <linux/export.h>
10 #include <linux/ide.h>
11 #include <linux/scatterlist.h>
12 #include <linux/gfp.h>
13
14 #include <scsi/scsi.h>
15
16 #define DRV_NAME "ide-atapi"
17 #define PFX DRV_NAME ": "
18
19 #ifdef DEBUG
20 #define debug_log(fmt, args...) \
21         printk(KERN_INFO "ide: " fmt, ## args)
22 #else
23 #define debug_log(fmt, args...) do {} while (0)
24 #endif
25
26 #define ATAPI_MIN_CDB_BYTES     12
27
28 static inline int dev_is_idecd(ide_drive_t *drive)
29 {
30         return drive->media == ide_cdrom || drive->media == ide_optical;
31 }
32
33 /*
34  * Check whether we can support a device,
35  * based on the ATAPI IDENTIFY command results.
36  */
37 int ide_check_atapi_device(ide_drive_t *drive, const char *s)
38 {
39         u16 *id = drive->id;
40         u8 gcw[2], protocol, device_type, removable, drq_type, packet_size;
41
42         *((u16 *)&gcw) = id[ATA_ID_CONFIG];
43
44         protocol    = (gcw[1] & 0xC0) >> 6;
45         device_type =  gcw[1] & 0x1F;
46         removable   = (gcw[0] & 0x80) >> 7;
47         drq_type    = (gcw[0] & 0x60) >> 5;
48         packet_size =  gcw[0] & 0x03;
49
50 #ifdef CONFIG_PPC
51         /* kludge for Apple PowerBook internal zip */
52         if (drive->media == ide_floppy && device_type == 5 &&
53             !strstr((char *)&id[ATA_ID_PROD], "CD-ROM") &&
54             strstr((char *)&id[ATA_ID_PROD], "ZIP"))
55                 device_type = 0;
56 #endif
57
58         if (protocol != 2)
59                 printk(KERN_ERR "%s: %s: protocol (0x%02x) is not ATAPI\n",
60                         s, drive->name, protocol);
61         else if ((drive->media == ide_floppy && device_type != 0) ||
62                  (drive->media == ide_tape && device_type != 1))
63                 printk(KERN_ERR "%s: %s: invalid device type (0x%02x)\n",
64                         s, drive->name, device_type);
65         else if (removable == 0)
66                 printk(KERN_ERR "%s: %s: the removable flag is not set\n",
67                         s, drive->name);
68         else if (drive->media == ide_floppy && drq_type == 3)
69                 printk(KERN_ERR "%s: %s: sorry, DRQ type (0x%02x) not "
70                         "supported\n", s, drive->name, drq_type);
71         else if (packet_size != 0)
72                 printk(KERN_ERR "%s: %s: packet size (0x%02x) is not 12 "
73                         "bytes\n", s, drive->name, packet_size);
74         else
75                 return 1;
76         return 0;
77 }
78 EXPORT_SYMBOL_GPL(ide_check_atapi_device);
79
80 void ide_init_pc(struct ide_atapi_pc *pc)
81 {
82         memset(pc, 0, sizeof(*pc));
83 }
84 EXPORT_SYMBOL_GPL(ide_init_pc);
85
86 /*
87  * Add a special packet command request to the tail of the request queue,
88  * and wait for it to be serviced.
89  */
90 int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk,
91                       struct ide_atapi_pc *pc, void *buf, unsigned int bufflen)
92 {
93         struct request *rq;
94         int error;
95
96         rq = blk_get_request(drive->queue, REQ_OP_DRV_IN, 0);
97         ide_req(rq)->type = ATA_PRIV_MISC;
98         ide_req(rq)->special = pc;
99
100         if (buf && bufflen) {
101                 error = blk_rq_map_kern(drive->queue, rq, buf, bufflen,
102                                         GFP_NOIO);
103                 if (error)
104                         goto put_req;
105         }
106
107         memcpy(scsi_req(rq)->cmd, pc->c, 12);
108         if (drive->media == ide_tape)
109                 scsi_req(rq)->cmd[13] = REQ_IDETAPE_PC1;
110         blk_execute_rq(drive->queue, disk, rq, 0);
111         error = scsi_req(rq)->result ? -EIO : 0;
112 put_req:
113         blk_put_request(rq);
114         return error;
115 }
116 EXPORT_SYMBOL_GPL(ide_queue_pc_tail);
117
118 int ide_do_test_unit_ready(ide_drive_t *drive, struct gendisk *disk)
119 {
120         struct ide_atapi_pc pc;
121
122         ide_init_pc(&pc);
123         pc.c[0] = TEST_UNIT_READY;
124
125         return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
126 }
127 EXPORT_SYMBOL_GPL(ide_do_test_unit_ready);
128
129 int ide_do_start_stop(ide_drive_t *drive, struct gendisk *disk, int start)
130 {
131         struct ide_atapi_pc pc;
132
133         ide_init_pc(&pc);
134         pc.c[0] = START_STOP;
135         pc.c[4] = start;
136
137         if (drive->media == ide_tape)
138                 pc.flags |= PC_FLAG_WAIT_FOR_DSC;
139
140         return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
141 }
142 EXPORT_SYMBOL_GPL(ide_do_start_stop);
143
144 int ide_set_media_lock(ide_drive_t *drive, struct gendisk *disk, int on)
145 {
146         struct ide_atapi_pc pc;
147
148         if ((drive->dev_flags & IDE_DFLAG_DOORLOCKING) == 0)
149                 return 0;
150
151         ide_init_pc(&pc);
152         pc.c[0] = ALLOW_MEDIUM_REMOVAL;
153         pc.c[4] = on;
154
155         return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
156 }
157 EXPORT_SYMBOL_GPL(ide_set_media_lock);
158
159 void ide_create_request_sense_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc)
160 {
161         ide_init_pc(pc);
162         pc->c[0] = REQUEST_SENSE;
163         if (drive->media == ide_floppy) {
164                 pc->c[4] = 255;
165                 pc->req_xfer = 18;
166         } else {
167                 pc->c[4] = 20;
168                 pc->req_xfer = 20;
169         }
170 }
171 EXPORT_SYMBOL_GPL(ide_create_request_sense_cmd);
172
173 void ide_prep_sense(ide_drive_t *drive, struct request *rq)
174 {
175         struct request_sense *sense = &drive->sense_data;
176         struct request *sense_rq;
177         struct scsi_request *req;
178         unsigned int cmd_len, sense_len;
179         int err;
180
181         switch (drive->media) {
182         case ide_floppy:
183                 cmd_len = 255;
184                 sense_len = 18;
185                 break;
186         case ide_tape:
187                 cmd_len = 20;
188                 sense_len = 20;
189                 break;
190         default:
191                 cmd_len = 18;
192                 sense_len = 18;
193         }
194
195         BUG_ON(sense_len > sizeof(*sense));
196
197         if (ata_sense_request(rq) || drive->sense_rq_armed)
198                 return;
199
200         sense_rq = drive->sense_rq;
201         if (!sense_rq) {
202                 sense_rq = blk_mq_alloc_request(drive->queue, REQ_OP_DRV_IN,
203                                         BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
204                 drive->sense_rq = sense_rq;
205         }
206         req = scsi_req(sense_rq);
207
208         memset(sense, 0, sizeof(*sense));
209
210         scsi_req_init(req);
211
212         err = blk_rq_map_kern(drive->queue, sense_rq, sense, sense_len,
213                               GFP_NOIO);
214         if (unlikely(err)) {
215                 if (printk_ratelimit())
216                         printk(KERN_WARNING PFX "%s: failed to map sense "
217                                             "buffer\n", drive->name);
218                 blk_mq_free_request(sense_rq);
219                 drive->sense_rq = NULL;
220                 return;
221         }
222
223         sense_rq->rq_disk = rq->rq_disk;
224         sense_rq->cmd_flags = REQ_OP_DRV_IN;
225         ide_req(sense_rq)->type = ATA_PRIV_SENSE;
226
227         req->cmd[0] = GPCMD_REQUEST_SENSE;
228         req->cmd[4] = cmd_len;
229         if (drive->media == ide_tape)
230                 req->cmd[13] = REQ_IDETAPE_PC1;
231
232         drive->sense_rq_armed = true;
233 }
234 EXPORT_SYMBOL_GPL(ide_prep_sense);
235
236 int ide_queue_sense_rq(ide_drive_t *drive, void *special)
237 {
238         ide_hwif_t *hwif = drive->hwif;
239         struct request *sense_rq;
240         unsigned long flags;
241
242         spin_lock_irqsave(&hwif->lock, flags);
243
244         /* deferred failure from ide_prep_sense() */
245         if (!drive->sense_rq_armed) {
246                 printk(KERN_WARNING PFX "%s: error queuing a sense request\n",
247                        drive->name);
248                 spin_unlock_irqrestore(&hwif->lock, flags);
249                 return -ENOMEM;
250         }
251
252         sense_rq = drive->sense_rq;
253         ide_req(sense_rq)->special = special;
254         drive->sense_rq_armed = false;
255
256         drive->hwif->rq = NULL;
257
258         ide_insert_request_head(drive, sense_rq);
259         spin_unlock_irqrestore(&hwif->lock, flags);
260         return 0;
261 }
262 EXPORT_SYMBOL_GPL(ide_queue_sense_rq);
263
264 /*
265  * Called when an error was detected during the last packet command.
266  * We queue a request sense packet command at the head of the request
267  * queue.
268  */
269 void ide_retry_pc(ide_drive_t *drive)
270 {
271         struct request *failed_rq = drive->hwif->rq;
272         struct request *sense_rq = drive->sense_rq;
273         struct ide_atapi_pc *pc = &drive->request_sense_pc;
274
275         (void)ide_read_error(drive);
276
277         /* init pc from sense_rq */
278         ide_init_pc(pc);
279         memcpy(pc->c, scsi_req(sense_rq)->cmd, 12);
280
281         if (drive->media == ide_tape)
282                 drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
283
284         /*
285          * Push back the failed request and put request sense on top
286          * of it.  The failed command will be retried after sense data
287          * is acquired.
288          */
289         drive->hwif->rq = NULL;
290         ide_requeue_and_plug(drive, failed_rq);
291         if (ide_queue_sense_rq(drive, pc))
292                 ide_complete_rq(drive, BLK_STS_IOERR, blk_rq_bytes(failed_rq));
293 }
294 EXPORT_SYMBOL_GPL(ide_retry_pc);
295
296 int ide_cd_expiry(ide_drive_t *drive)
297 {
298         struct request *rq = drive->hwif->rq;
299         unsigned long wait = 0;
300
301         debug_log("%s: scsi_req(rq)->cmd[0]: 0x%x\n", __func__, scsi_req(rq)->cmd[0]);
302
303         /*
304          * Some commands are *slow* and normally take a long time to complete.
305          * Usually we can use the ATAPI "disconnect" to bypass this, but not all
306          * commands/drives support that. Let ide_timer_expiry keep polling us
307          * for these.
308          */
309         switch (scsi_req(rq)->cmd[0]) {
310         case GPCMD_BLANK:
311         case GPCMD_FORMAT_UNIT:
312         case GPCMD_RESERVE_RZONE_TRACK:
313         case GPCMD_CLOSE_TRACK:
314         case GPCMD_FLUSH_CACHE:
315                 wait = ATAPI_WAIT_PC;
316                 break;
317         default:
318                 if (!(rq->rq_flags & RQF_QUIET))
319                         printk(KERN_INFO PFX "cmd 0x%x timed out\n",
320                                          scsi_req(rq)->cmd[0]);
321                 wait = 0;
322                 break;
323         }
324         return wait;
325 }
326 EXPORT_SYMBOL_GPL(ide_cd_expiry);
327
328 int ide_cd_get_xferlen(struct request *rq)
329 {
330         switch (req_op(rq)) {
331         default:
332                 return 32768;
333         case REQ_OP_SCSI_IN:
334         case REQ_OP_SCSI_OUT:
335                 return blk_rq_bytes(rq);
336         case REQ_OP_DRV_IN:
337         case REQ_OP_DRV_OUT:
338                 switch (ide_req(rq)->type) {
339                 case ATA_PRIV_PC:
340                 case ATA_PRIV_SENSE:
341                         return blk_rq_bytes(rq);
342                 default:
343                         return 0;
344                 }
345         }
346 }
347 EXPORT_SYMBOL_GPL(ide_cd_get_xferlen);
348
349 void ide_read_bcount_and_ireason(ide_drive_t *drive, u16 *bcount, u8 *ireason)
350 {
351         struct ide_taskfile tf;
352
353         drive->hwif->tp_ops->tf_read(drive, &tf, IDE_VALID_NSECT |
354                                      IDE_VALID_LBAM | IDE_VALID_LBAH);
355
356         *bcount = (tf.lbah << 8) | tf.lbam;
357         *ireason = tf.nsect & 3;
358 }
359 EXPORT_SYMBOL_GPL(ide_read_bcount_and_ireason);
360
361 /*
362  * Check the contents of the interrupt reason register and attempt to recover if
363  * there are problems.
364  *
365  * Returns:
366  * - 0 if everything's ok
367  * - 1 if the request has to be terminated.
368  */
369 int ide_check_ireason(ide_drive_t *drive, struct request *rq, int len,
370                       int ireason, int rw)
371 {
372         ide_hwif_t *hwif = drive->hwif;
373
374         debug_log("ireason: 0x%x, rw: 0x%x\n", ireason, rw);
375
376         if (ireason == (!rw << 1))
377                 return 0;
378         else if (ireason == (rw << 1)) {
379                 printk(KERN_ERR PFX "%s: %s: wrong transfer direction!\n",
380                                 drive->name, __func__);
381
382                 if (dev_is_idecd(drive))
383                         ide_pad_transfer(drive, rw, len);
384         } else if (!rw && ireason == ATAPI_COD) {
385                 if (dev_is_idecd(drive)) {
386                         /*
387                          * Some drives (ASUS) seem to tell us that status info
388                          * is available.  Just get it and ignore.
389                          */
390                         (void)hwif->tp_ops->read_status(hwif);
391                         return 0;
392                 }
393         } else {
394                 if (ireason & ATAPI_COD)
395                         printk(KERN_ERR PFX "%s: CoD != 0 in %s\n", drive->name,
396                                         __func__);
397
398                 /* drive wants a command packet, or invalid ireason... */
399                 printk(KERN_ERR PFX "%s: %s: bad interrupt reason 0x%02x\n",
400                                 drive->name, __func__, ireason);
401         }
402
403         if (dev_is_idecd(drive) && ata_pc_request(rq))
404                 rq->rq_flags |= RQF_FAILED;
405
406         return 1;
407 }
408 EXPORT_SYMBOL_GPL(ide_check_ireason);
409
410 /*
411  * This is the usual interrupt handler which will be called during a packet
412  * command.  We will transfer some of the data (as requested by the drive)
413  * and will re-point interrupt handler to us.
414  */
415 static ide_startstop_t ide_pc_intr(ide_drive_t *drive)
416 {
417         struct ide_atapi_pc *pc = drive->pc;
418         ide_hwif_t *hwif = drive->hwif;
419         struct ide_cmd *cmd = &hwif->cmd;
420         struct request *rq = hwif->rq;
421         const struct ide_tp_ops *tp_ops = hwif->tp_ops;
422         unsigned int timeout, done;
423         u16 bcount;
424         u8 stat, ireason, dsc = 0;
425         u8 write = !!(pc->flags & PC_FLAG_WRITING);
426
427         debug_log("Enter %s - interrupt handler\n", __func__);
428
429         timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
430                                                : WAIT_TAPE_CMD;
431
432         /* Clear the interrupt */
433         stat = tp_ops->read_status(hwif);
434
435         if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
436                 int rc;
437
438                 drive->waiting_for_dma = 0;
439                 rc = hwif->dma_ops->dma_end(drive);
440                 ide_dma_unmap_sg(drive, cmd);
441
442                 if (rc || (drive->media == ide_tape && (stat & ATA_ERR))) {
443                         if (drive->media == ide_floppy)
444                                 printk(KERN_ERR PFX "%s: DMA %s error\n",
445                                         drive->name, rq_data_dir(pc->rq)
446                                                      ? "write" : "read");
447                         pc->flags |= PC_FLAG_DMA_ERROR;
448                 } else
449                         scsi_req(rq)->resid_len = 0;
450                 debug_log("%s: DMA finished\n", drive->name);
451         }
452
453         /* No more interrupts */
454         if ((stat & ATA_DRQ) == 0) {
455                 int uptodate;
456                 blk_status_t error;
457
458                 debug_log("Packet command completed, %d bytes transferred\n",
459                           blk_rq_bytes(rq));
460
461                 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
462
463                 local_irq_enable_in_hardirq();
464
465                 if (drive->media == ide_tape &&
466                     (stat & ATA_ERR) && scsi_req(rq)->cmd[0] == REQUEST_SENSE)
467                         stat &= ~ATA_ERR;
468
469                 if ((stat & ATA_ERR) || (pc->flags & PC_FLAG_DMA_ERROR)) {
470                         /* Error detected */
471                         debug_log("%s: I/O error\n", drive->name);
472
473                         if (drive->media != ide_tape)
474                                 scsi_req(pc->rq)->result++;
475
476                         if (scsi_req(rq)->cmd[0] == REQUEST_SENSE) {
477                                 printk(KERN_ERR PFX "%s: I/O error in request "
478                                                 "sense command\n", drive->name);
479                                 return ide_do_reset(drive);
480                         }
481
482                         debug_log("[cmd %x]: check condition\n", scsi_req(rq)->cmd[0]);
483
484                         /* Retry operation */
485                         ide_retry_pc(drive);
486
487                         /* queued, but not started */
488                         return ide_stopped;
489                 }
490                 pc->error = 0;
491
492                 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0)
493                         dsc = 1;
494
495                 /*
496                  * ->pc_callback() might change rq->data_len for
497                  * residual count, cache total length.
498                  */
499                 done = blk_rq_bytes(rq);
500
501                 /* Command finished - Call the callback function */
502                 uptodate = drive->pc_callback(drive, dsc);
503
504                 if (uptodate == 0)
505                         drive->failed_pc = NULL;
506
507                 if (ata_misc_request(rq)) {
508                         scsi_req(rq)->result = 0;
509                         error = BLK_STS_OK;
510                 } else {
511
512                         if (blk_rq_is_passthrough(rq) && uptodate <= 0) {
513                                 if (scsi_req(rq)->result == 0)
514                                         scsi_req(rq)->result = -EIO;
515                         }
516
517                         error = uptodate ? BLK_STS_OK : BLK_STS_IOERR;
518                 }
519
520                 ide_complete_rq(drive, error, blk_rq_bytes(rq));
521                 return ide_stopped;
522         }
523
524         if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
525                 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
526                 printk(KERN_ERR PFX "%s: The device wants to issue more "
527                                 "interrupts in DMA mode\n", drive->name);
528                 ide_dma_off(drive);
529                 return ide_do_reset(drive);
530         }
531
532         /* Get the number of bytes to transfer on this interrupt. */
533         ide_read_bcount_and_ireason(drive, &bcount, &ireason);
534
535         if (ide_check_ireason(drive, rq, bcount, ireason, write))
536                 return ide_do_reset(drive);
537
538         done = min_t(unsigned int, bcount, cmd->nleft);
539         ide_pio_bytes(drive, cmd, write, done);
540
541         /* Update transferred byte count */
542         scsi_req(rq)->resid_len -= done;
543
544         bcount -= done;
545
546         if (bcount)
547                 ide_pad_transfer(drive, write, bcount);
548
549         debug_log("[cmd %x] transferred %d bytes, padded %d bytes, resid: %u\n",
550                   scsi_req(rq)->cmd[0], done, bcount, scsi_req(rq)->resid_len);
551
552         /* And set the interrupt handler again */
553         ide_set_handler(drive, ide_pc_intr, timeout);
554         return ide_started;
555 }
556
557 static void ide_init_packet_cmd(struct ide_cmd *cmd, u8 valid_tf,
558                                 u16 bcount, u8 dma)
559 {
560         cmd->protocol = dma ? ATAPI_PROT_DMA : ATAPI_PROT_PIO;
561         cmd->valid.out.tf = IDE_VALID_LBAH | IDE_VALID_LBAM |
562                             IDE_VALID_FEATURE | valid_tf;
563         cmd->tf.command = ATA_CMD_PACKET;
564         cmd->tf.feature = dma;          /* Use PIO/DMA */
565         cmd->tf.lbam    = bcount & 0xff;
566         cmd->tf.lbah    = (bcount >> 8) & 0xff;
567 }
568
569 static u8 ide_read_ireason(ide_drive_t *drive)
570 {
571         struct ide_taskfile tf;
572
573         drive->hwif->tp_ops->tf_read(drive, &tf, IDE_VALID_NSECT);
574
575         return tf.nsect & 3;
576 }
577
578 static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason)
579 {
580         int retries = 100;
581
582         while (retries-- && ((ireason & ATAPI_COD) == 0 ||
583                 (ireason & ATAPI_IO))) {
584                 printk(KERN_ERR PFX "%s: (IO,CoD != (0,1) while issuing "
585                                 "a packet command, retrying\n", drive->name);
586                 udelay(100);
587                 ireason = ide_read_ireason(drive);
588                 if (retries == 0) {
589                         printk(KERN_ERR PFX "%s: (IO,CoD != (0,1) while issuing"
590                                         " a packet command, ignoring\n",
591                                         drive->name);
592                         ireason |= ATAPI_COD;
593                         ireason &= ~ATAPI_IO;
594                 }
595         }
596
597         return ireason;
598 }
599
600 static int ide_delayed_transfer_pc(ide_drive_t *drive)
601 {
602         /* Send the actual packet */
603         drive->hwif->tp_ops->output_data(drive, NULL, drive->pc->c, 12);
604
605         /* Timeout for the packet command */
606         return WAIT_FLOPPY_CMD;
607 }
608
609 static ide_startstop_t ide_transfer_pc(ide_drive_t *drive)
610 {
611         struct ide_atapi_pc *pc;
612         ide_hwif_t *hwif = drive->hwif;
613         struct request *rq = hwif->rq;
614         ide_expiry_t *expiry;
615         unsigned int timeout;
616         int cmd_len;
617         ide_startstop_t startstop;
618         u8 ireason;
619
620         if (ide_wait_stat(&startstop, drive, ATA_DRQ, ATA_BUSY, WAIT_READY)) {
621                 printk(KERN_ERR PFX "%s: Strange, packet command initiated yet "
622                                 "DRQ isn't asserted\n", drive->name);
623                 return startstop;
624         }
625
626         if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) {
627                 if (drive->dma)
628                         drive->waiting_for_dma = 1;
629         }
630
631         if (dev_is_idecd(drive)) {
632                 /* ATAPI commands get padded out to 12 bytes minimum */
633                 cmd_len = COMMAND_SIZE(scsi_req(rq)->cmd[0]);
634                 if (cmd_len < ATAPI_MIN_CDB_BYTES)
635                         cmd_len = ATAPI_MIN_CDB_BYTES;
636
637                 timeout = rq->timeout;
638                 expiry  = ide_cd_expiry;
639         } else {
640                 pc = drive->pc;
641
642                 cmd_len = ATAPI_MIN_CDB_BYTES;
643
644                 /*
645                  * If necessary schedule the packet transfer to occur 'timeout'
646                  * milliseconds later in ide_delayed_transfer_pc() after the
647                  * device says it's ready for a packet.
648                  */
649                 if (drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) {
650                         timeout = drive->pc_delay;
651                         expiry = &ide_delayed_transfer_pc;
652                 } else {
653                         timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
654                                                                : WAIT_TAPE_CMD;
655                         expiry = NULL;
656                 }
657
658                 ireason = ide_read_ireason(drive);
659                 if (drive->media == ide_tape)
660                         ireason = ide_wait_ireason(drive, ireason);
661
662                 if ((ireason & ATAPI_COD) == 0 || (ireason & ATAPI_IO)) {
663                         printk(KERN_ERR PFX "%s: (IO,CoD) != (0,1) while "
664                                 "issuing a packet command\n", drive->name);
665
666                         return ide_do_reset(drive);
667                 }
668         }
669
670         hwif->expiry = expiry;
671
672         /* Set the interrupt routine */
673         ide_set_handler(drive,
674                         (dev_is_idecd(drive) ? drive->irq_handler
675                                              : ide_pc_intr),
676                         timeout);
677
678         /* Send the actual packet */
679         if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0)
680                 hwif->tp_ops->output_data(drive, NULL, scsi_req(rq)->cmd, cmd_len);
681
682         /* Begin DMA, if necessary */
683         if (dev_is_idecd(drive)) {
684                 if (drive->dma)
685                         hwif->dma_ops->dma_start(drive);
686         } else {
687                 if (pc->flags & PC_FLAG_DMA_OK) {
688                         pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
689                         hwif->dma_ops->dma_start(drive);
690                 }
691         }
692
693         return ide_started;
694 }
695
696 ide_startstop_t ide_issue_pc(ide_drive_t *drive, struct ide_cmd *cmd)
697 {
698         struct ide_atapi_pc *pc;
699         ide_hwif_t *hwif = drive->hwif;
700         ide_expiry_t *expiry = NULL;
701         struct request *rq = hwif->rq;
702         unsigned int timeout, bytes;
703         u16 bcount;
704         u8 valid_tf;
705         u8 drq_int = !!(drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT);
706
707         if (dev_is_idecd(drive)) {
708                 valid_tf = IDE_VALID_NSECT | IDE_VALID_LBAL;
709                 bcount = ide_cd_get_xferlen(rq);
710                 expiry = ide_cd_expiry;
711                 timeout = ATAPI_WAIT_PC;
712
713                 if (drive->dma)
714                         drive->dma = !ide_dma_prepare(drive, cmd);
715         } else {
716                 pc = drive->pc;
717
718                 valid_tf = IDE_VALID_DEVICE;
719                 bytes = blk_rq_bytes(rq);
720                 bcount = ((drive->media == ide_tape) ? bytes
721                                                      : min_t(unsigned int,
722                                                              bytes, 63 * 1024));
723
724                 /* We haven't transferred any data yet */
725                 scsi_req(rq)->resid_len = bcount;
726
727                 if (pc->flags & PC_FLAG_DMA_ERROR) {
728                         pc->flags &= ~PC_FLAG_DMA_ERROR;
729                         ide_dma_off(drive);
730                 }
731
732                 if (pc->flags & PC_FLAG_DMA_OK)
733                         drive->dma = !ide_dma_prepare(drive, cmd);
734
735                 if (!drive->dma)
736                         pc->flags &= ~PC_FLAG_DMA_OK;
737
738                 timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
739                                                        : WAIT_TAPE_CMD;
740         }
741
742         ide_init_packet_cmd(cmd, valid_tf, bcount, drive->dma);
743
744         (void)do_rw_taskfile(drive, cmd);
745
746         if (drq_int) {
747                 if (drive->dma)
748                         drive->waiting_for_dma = 0;
749                 hwif->expiry = expiry;
750         }
751
752         ide_execute_command(drive, cmd, ide_transfer_pc, timeout);
753
754         return drq_int ? ide_started : ide_transfer_pc(drive);
755 }
756 EXPORT_SYMBOL_GPL(ide_issue_pc);