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