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v3.1
  1/*
  2 * ATAPI support.
  3 */
  4
  5#include <linux/kernel.h>
  6#include <linux/cdrom.h>
  7#include <linux/delay.h>
 
  8#include <linux/ide.h>
  9#include <linux/scatterlist.h>
 10#include <linux/gfp.h>
 11
 12#include <scsi/scsi.h>
 13
 14#define DRV_NAME "ide-atapi"
 15#define PFX DRV_NAME ": "
 16
 17#ifdef DEBUG
 18#define debug_log(fmt, args...) \
 19	printk(KERN_INFO "ide: " fmt, ## args)
 20#else
 21#define debug_log(fmt, args...) do {} while (0)
 22#endif
 23
 24#define ATAPI_MIN_CDB_BYTES	12
 25
 26static inline int dev_is_idecd(ide_drive_t *drive)
 27{
 28	return drive->media == ide_cdrom || drive->media == ide_optical;
 29}
 30
 31/*
 32 * Check whether we can support a device,
 33 * based on the ATAPI IDENTIFY command results.
 34 */
 35int ide_check_atapi_device(ide_drive_t *drive, const char *s)
 36{
 37	u16 *id = drive->id;
 38	u8 gcw[2], protocol, device_type, removable, drq_type, packet_size;
 39
 40	*((u16 *)&gcw) = id[ATA_ID_CONFIG];
 41
 42	protocol    = (gcw[1] & 0xC0) >> 6;
 43	device_type =  gcw[1] & 0x1F;
 44	removable   = (gcw[0] & 0x80) >> 7;
 45	drq_type    = (gcw[0] & 0x60) >> 5;
 46	packet_size =  gcw[0] & 0x03;
 47
 48#ifdef CONFIG_PPC
 49	/* kludge for Apple PowerBook internal zip */
 50	if (drive->media == ide_floppy && device_type == 5 &&
 51	    !strstr((char *)&id[ATA_ID_PROD], "CD-ROM") &&
 52	    strstr((char *)&id[ATA_ID_PROD], "ZIP"))
 53		device_type = 0;
 54#endif
 55
 56	if (protocol != 2)
 57		printk(KERN_ERR "%s: %s: protocol (0x%02x) is not ATAPI\n",
 58			s, drive->name, protocol);
 59	else if ((drive->media == ide_floppy && device_type != 0) ||
 60		 (drive->media == ide_tape && device_type != 1))
 61		printk(KERN_ERR "%s: %s: invalid device type (0x%02x)\n",
 62			s, drive->name, device_type);
 63	else if (removable == 0)
 64		printk(KERN_ERR "%s: %s: the removable flag is not set\n",
 65			s, drive->name);
 66	else if (drive->media == ide_floppy && drq_type == 3)
 67		printk(KERN_ERR "%s: %s: sorry, DRQ type (0x%02x) not "
 68			"supported\n", s, drive->name, drq_type);
 69	else if (packet_size != 0)
 70		printk(KERN_ERR "%s: %s: packet size (0x%02x) is not 12 "
 71			"bytes\n", s, drive->name, packet_size);
 72	else
 73		return 1;
 74	return 0;
 75}
 76EXPORT_SYMBOL_GPL(ide_check_atapi_device);
 77
 78void ide_init_pc(struct ide_atapi_pc *pc)
 79{
 80	memset(pc, 0, sizeof(*pc));
 81}
 82EXPORT_SYMBOL_GPL(ide_init_pc);
 83
 84/*
 85 * Add a special packet command request to the tail of the request queue,
 86 * and wait for it to be serviced.
 87 */
 88int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk,
 89		      struct ide_atapi_pc *pc, void *buf, unsigned int bufflen)
 90{
 91	struct request *rq;
 92	int error;
 93
 94	rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
 95	rq->cmd_type = REQ_TYPE_SPECIAL;
 96	rq->special = (char *)pc;
 97
 98	if (buf && bufflen) {
 99		error = blk_rq_map_kern(drive->queue, rq, buf, bufflen,
100					GFP_NOIO);
101		if (error)
102			goto put_req;
103	}
104
105	memcpy(rq->cmd, pc->c, 12);
106	if (drive->media == ide_tape)
107		rq->cmd[13] = REQ_IDETAPE_PC1;
108	error = blk_execute_rq(drive->queue, disk, rq, 0);
 
109put_req:
110	blk_put_request(rq);
111	return error;
112}
113EXPORT_SYMBOL_GPL(ide_queue_pc_tail);
114
115int ide_do_test_unit_ready(ide_drive_t *drive, struct gendisk *disk)
116{
117	struct ide_atapi_pc pc;
118
119	ide_init_pc(&pc);
120	pc.c[0] = TEST_UNIT_READY;
121
122	return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
123}
124EXPORT_SYMBOL_GPL(ide_do_test_unit_ready);
125
126int ide_do_start_stop(ide_drive_t *drive, struct gendisk *disk, int start)
127{
128	struct ide_atapi_pc pc;
129
130	ide_init_pc(&pc);
131	pc.c[0] = START_STOP;
132	pc.c[4] = start;
133
134	if (drive->media == ide_tape)
135		pc.flags |= PC_FLAG_WAIT_FOR_DSC;
136
137	return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
138}
139EXPORT_SYMBOL_GPL(ide_do_start_stop);
140
141int ide_set_media_lock(ide_drive_t *drive, struct gendisk *disk, int on)
142{
143	struct ide_atapi_pc pc;
144
145	if ((drive->dev_flags & IDE_DFLAG_DOORLOCKING) == 0)
146		return 0;
147
148	ide_init_pc(&pc);
149	pc.c[0] = ALLOW_MEDIUM_REMOVAL;
150	pc.c[4] = on;
151
152	return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
153}
154EXPORT_SYMBOL_GPL(ide_set_media_lock);
155
156void ide_create_request_sense_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc)
157{
158	ide_init_pc(pc);
159	pc->c[0] = REQUEST_SENSE;
160	if (drive->media == ide_floppy) {
161		pc->c[4] = 255;
162		pc->req_xfer = 18;
163	} else {
164		pc->c[4] = 20;
165		pc->req_xfer = 20;
166	}
167}
168EXPORT_SYMBOL_GPL(ide_create_request_sense_cmd);
169
170void ide_prep_sense(ide_drive_t *drive, struct request *rq)
171{
172	struct request_sense *sense = &drive->sense_data;
173	struct request *sense_rq = &drive->sense_rq;
 
174	unsigned int cmd_len, sense_len;
175	int err;
176
177	switch (drive->media) {
178	case ide_floppy:
179		cmd_len = 255;
180		sense_len = 18;
181		break;
182	case ide_tape:
183		cmd_len = 20;
184		sense_len = 20;
185		break;
186	default:
187		cmd_len = 18;
188		sense_len = 18;
189	}
190
191	BUG_ON(sense_len > sizeof(*sense));
192
193	if (rq->cmd_type == REQ_TYPE_SENSE || drive->sense_rq_armed)
194		return;
195
196	memset(sense, 0, sizeof(*sense));
197
198	blk_rq_init(rq->q, sense_rq);
 
199
200	err = blk_rq_map_kern(drive->queue, sense_rq, sense, sense_len,
201			      GFP_NOIO);
202	if (unlikely(err)) {
203		if (printk_ratelimit())
204			printk(KERN_WARNING PFX "%s: failed to map sense "
205					    "buffer\n", drive->name);
206		return;
207	}
208
209	sense_rq->rq_disk = rq->rq_disk;
210	sense_rq->cmd[0] = GPCMD_REQUEST_SENSE;
211	sense_rq->cmd[4] = cmd_len;
212	sense_rq->cmd_type = REQ_TYPE_SENSE;
213	sense_rq->cmd_flags |= REQ_PREEMPT;
214
 
 
215	if (drive->media == ide_tape)
216		sense_rq->cmd[13] = REQ_IDETAPE_PC1;
217
218	drive->sense_rq_armed = true;
219}
220EXPORT_SYMBOL_GPL(ide_prep_sense);
221
222int ide_queue_sense_rq(ide_drive_t *drive, void *special)
223{
224	/* deferred failure from ide_prep_sense() */
225	if (!drive->sense_rq_armed) {
226		printk(KERN_WARNING PFX "%s: error queuing a sense request\n",
227		       drive->name);
228		return -ENOMEM;
229	}
230
231	drive->sense_rq.special = special;
232	drive->sense_rq_armed = false;
233
234	drive->hwif->rq = NULL;
235
236	elv_add_request(drive->queue, &drive->sense_rq, ELEVATOR_INSERT_FRONT);
237	return 0;
238}
239EXPORT_SYMBOL_GPL(ide_queue_sense_rq);
240
241/*
242 * Called when an error was detected during the last packet command.
243 * We queue a request sense packet command at the head of the request
244 * queue.
245 */
246void ide_retry_pc(ide_drive_t *drive)
247{
248	struct request *failed_rq = drive->hwif->rq;
249	struct request *sense_rq = &drive->sense_rq;
250	struct ide_atapi_pc *pc = &drive->request_sense_pc;
251
252	(void)ide_read_error(drive);
253
254	/* init pc from sense_rq */
255	ide_init_pc(pc);
256	memcpy(pc->c, sense_rq->cmd, 12);
257
258	if (drive->media == ide_tape)
259		drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
260
261	/*
262	 * Push back the failed request and put request sense on top
263	 * of it.  The failed command will be retried after sense data
264	 * is acquired.
265	 */
266	drive->hwif->rq = NULL;
267	ide_requeue_and_plug(drive, failed_rq);
268	if (ide_queue_sense_rq(drive, pc)) {
269		blk_start_request(failed_rq);
270		ide_complete_rq(drive, -EIO, blk_rq_bytes(failed_rq));
271	}
272}
273EXPORT_SYMBOL_GPL(ide_retry_pc);
274
275int ide_cd_expiry(ide_drive_t *drive)
276{
277	struct request *rq = drive->hwif->rq;
278	unsigned long wait = 0;
279
280	debug_log("%s: rq->cmd[0]: 0x%x\n", __func__, rq->cmd[0]);
281
282	/*
283	 * Some commands are *slow* and normally take a long time to complete.
284	 * Usually we can use the ATAPI "disconnect" to bypass this, but not all
285	 * commands/drives support that. Let ide_timer_expiry keep polling us
286	 * for these.
287	 */
288	switch (rq->cmd[0]) {
289	case GPCMD_BLANK:
290	case GPCMD_FORMAT_UNIT:
291	case GPCMD_RESERVE_RZONE_TRACK:
292	case GPCMD_CLOSE_TRACK:
293	case GPCMD_FLUSH_CACHE:
294		wait = ATAPI_WAIT_PC;
295		break;
296	default:
297		if (!(rq->cmd_flags & REQ_QUIET))
298			printk(KERN_INFO PFX "cmd 0x%x timed out\n",
299					 rq->cmd[0]);
300		wait = 0;
301		break;
302	}
303	return wait;
304}
305EXPORT_SYMBOL_GPL(ide_cd_expiry);
306
307int ide_cd_get_xferlen(struct request *rq)
308{
309	switch (rq->cmd_type) {
310	case REQ_TYPE_FS:
311		return 32768;
312	case REQ_TYPE_SENSE:
313	case REQ_TYPE_BLOCK_PC:
314	case REQ_TYPE_ATA_PC:
315		return blk_rq_bytes(rq);
316	default:
317		return 0;
 
 
 
 
 
 
 
318	}
319}
320EXPORT_SYMBOL_GPL(ide_cd_get_xferlen);
321
322void ide_read_bcount_and_ireason(ide_drive_t *drive, u16 *bcount, u8 *ireason)
323{
324	struct ide_taskfile tf;
325
326	drive->hwif->tp_ops->tf_read(drive, &tf, IDE_VALID_NSECT |
327				     IDE_VALID_LBAM | IDE_VALID_LBAH);
328
329	*bcount = (tf.lbah << 8) | tf.lbam;
330	*ireason = tf.nsect & 3;
331}
332EXPORT_SYMBOL_GPL(ide_read_bcount_and_ireason);
333
334/*
335 * Check the contents of the interrupt reason register and attempt to recover if
336 * there are problems.
337 *
338 * Returns:
339 * - 0 if everything's ok
340 * - 1 if the request has to be terminated.
341 */
342int ide_check_ireason(ide_drive_t *drive, struct request *rq, int len,
343		      int ireason, int rw)
344{
345	ide_hwif_t *hwif = drive->hwif;
346
347	debug_log("ireason: 0x%x, rw: 0x%x\n", ireason, rw);
348
349	if (ireason == (!rw << 1))
350		return 0;
351	else if (ireason == (rw << 1)) {
352		printk(KERN_ERR PFX "%s: %s: wrong transfer direction!\n",
353				drive->name, __func__);
354
355		if (dev_is_idecd(drive))
356			ide_pad_transfer(drive, rw, len);
357	} else if (!rw && ireason == ATAPI_COD) {
358		if (dev_is_idecd(drive)) {
359			/*
360			 * Some drives (ASUS) seem to tell us that status info
361			 * is available.  Just get it and ignore.
362			 */
363			(void)hwif->tp_ops->read_status(hwif);
364			return 0;
365		}
366	} else {
367		if (ireason & ATAPI_COD)
368			printk(KERN_ERR PFX "%s: CoD != 0 in %s\n", drive->name,
369					__func__);
370
371		/* drive wants a command packet, or invalid ireason... */
372		printk(KERN_ERR PFX "%s: %s: bad interrupt reason 0x%02x\n",
373				drive->name, __func__, ireason);
374	}
375
376	if (dev_is_idecd(drive) && rq->cmd_type == REQ_TYPE_ATA_PC)
377		rq->cmd_flags |= REQ_FAILED;
378
379	return 1;
380}
381EXPORT_SYMBOL_GPL(ide_check_ireason);
382
383/*
384 * This is the usual interrupt handler which will be called during a packet
385 * command.  We will transfer some of the data (as requested by the drive)
386 * and will re-point interrupt handler to us.
387 */
388static ide_startstop_t ide_pc_intr(ide_drive_t *drive)
389{
390	struct ide_atapi_pc *pc = drive->pc;
391	ide_hwif_t *hwif = drive->hwif;
392	struct ide_cmd *cmd = &hwif->cmd;
393	struct request *rq = hwif->rq;
394	const struct ide_tp_ops *tp_ops = hwif->tp_ops;
395	unsigned int timeout, done;
396	u16 bcount;
397	u8 stat, ireason, dsc = 0;
398	u8 write = !!(pc->flags & PC_FLAG_WRITING);
399
400	debug_log("Enter %s - interrupt handler\n", __func__);
401
402	timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
403					       : WAIT_TAPE_CMD;
404
405	/* Clear the interrupt */
406	stat = tp_ops->read_status(hwif);
407
408	if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
409		int rc;
410
411		drive->waiting_for_dma = 0;
412		rc = hwif->dma_ops->dma_end(drive);
413		ide_dma_unmap_sg(drive, cmd);
414
415		if (rc || (drive->media == ide_tape && (stat & ATA_ERR))) {
416			if (drive->media == ide_floppy)
417				printk(KERN_ERR PFX "%s: DMA %s error\n",
418					drive->name, rq_data_dir(pc->rq)
419						     ? "write" : "read");
420			pc->flags |= PC_FLAG_DMA_ERROR;
421		} else
422			rq->resid_len = 0;
423		debug_log("%s: DMA finished\n", drive->name);
424	}
425
426	/* No more interrupts */
427	if ((stat & ATA_DRQ) == 0) {
428		int uptodate, error;
 
429
430		debug_log("Packet command completed, %d bytes transferred\n",
431			  blk_rq_bytes(rq));
432
433		pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
434
435		local_irq_enable_in_hardirq();
436
437		if (drive->media == ide_tape &&
438		    (stat & ATA_ERR) && rq->cmd[0] == REQUEST_SENSE)
439			stat &= ~ATA_ERR;
440
441		if ((stat & ATA_ERR) || (pc->flags & PC_FLAG_DMA_ERROR)) {
442			/* Error detected */
443			debug_log("%s: I/O error\n", drive->name);
444
445			if (drive->media != ide_tape)
446				pc->rq->errors++;
447
448			if (rq->cmd[0] == REQUEST_SENSE) {
449				printk(KERN_ERR PFX "%s: I/O error in request "
450						"sense command\n", drive->name);
451				return ide_do_reset(drive);
452			}
453
454			debug_log("[cmd %x]: check condition\n", rq->cmd[0]);
455
456			/* Retry operation */
457			ide_retry_pc(drive);
458
459			/* queued, but not started */
460			return ide_stopped;
461		}
462		pc->error = 0;
463
464		if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0)
465			dsc = 1;
466
467		/*
468		 * ->pc_callback() might change rq->data_len for
469		 * residual count, cache total length.
470		 */
471		done = blk_rq_bytes(rq);
472
473		/* Command finished - Call the callback function */
474		uptodate = drive->pc_callback(drive, dsc);
475
476		if (uptodate == 0)
477			drive->failed_pc = NULL;
478
479		if (rq->cmd_type == REQ_TYPE_SPECIAL) {
480			rq->errors = 0;
481			error = 0;
482		} else {
483
484			if (rq->cmd_type != REQ_TYPE_FS && uptodate <= 0) {
485				if (rq->errors == 0)
486					rq->errors = -EIO;
487			}
488
489			error = uptodate ? 0 : -EIO;
490		}
491
492		ide_complete_rq(drive, error, blk_rq_bytes(rq));
493		return ide_stopped;
494	}
495
496	if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
497		pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
498		printk(KERN_ERR PFX "%s: The device wants to issue more "
499				"interrupts in DMA mode\n", drive->name);
500		ide_dma_off(drive);
501		return ide_do_reset(drive);
502	}
503
504	/* Get the number of bytes to transfer on this interrupt. */
505	ide_read_bcount_and_ireason(drive, &bcount, &ireason);
506
507	if (ide_check_ireason(drive, rq, bcount, ireason, write))
508		return ide_do_reset(drive);
509
510	done = min_t(unsigned int, bcount, cmd->nleft);
511	ide_pio_bytes(drive, cmd, write, done);
512
513	/* Update transferred byte count */
514	rq->resid_len -= done;
515
516	bcount -= done;
517
518	if (bcount)
519		ide_pad_transfer(drive, write, bcount);
520
521	debug_log("[cmd %x] transferred %d bytes, padded %d bytes, resid: %u\n",
522		  rq->cmd[0], done, bcount, rq->resid_len);
523
524	/* And set the interrupt handler again */
525	ide_set_handler(drive, ide_pc_intr, timeout);
526	return ide_started;
527}
528
529static void ide_init_packet_cmd(struct ide_cmd *cmd, u8 valid_tf,
530				u16 bcount, u8 dma)
531{
532	cmd->protocol = dma ? ATAPI_PROT_DMA : ATAPI_PROT_PIO;
533	cmd->valid.out.tf = IDE_VALID_LBAH | IDE_VALID_LBAM |
534			    IDE_VALID_FEATURE | valid_tf;
535	cmd->tf.command = ATA_CMD_PACKET;
536	cmd->tf.feature = dma;		/* Use PIO/DMA */
537	cmd->tf.lbam    = bcount & 0xff;
538	cmd->tf.lbah    = (bcount >> 8) & 0xff;
539}
540
541static u8 ide_read_ireason(ide_drive_t *drive)
542{
543	struct ide_taskfile tf;
544
545	drive->hwif->tp_ops->tf_read(drive, &tf, IDE_VALID_NSECT);
546
547	return tf.nsect & 3;
548}
549
550static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason)
551{
552	int retries = 100;
553
554	while (retries-- && ((ireason & ATAPI_COD) == 0 ||
555		(ireason & ATAPI_IO))) {
556		printk(KERN_ERR PFX "%s: (IO,CoD != (0,1) while issuing "
557				"a packet command, retrying\n", drive->name);
558		udelay(100);
559		ireason = ide_read_ireason(drive);
560		if (retries == 0) {
561			printk(KERN_ERR PFX "%s: (IO,CoD != (0,1) while issuing"
562					" a packet command, ignoring\n",
563					drive->name);
564			ireason |= ATAPI_COD;
565			ireason &= ~ATAPI_IO;
566		}
567	}
568
569	return ireason;
570}
571
572static int ide_delayed_transfer_pc(ide_drive_t *drive)
573{
574	/* Send the actual packet */
575	drive->hwif->tp_ops->output_data(drive, NULL, drive->pc->c, 12);
576
577	/* Timeout for the packet command */
578	return WAIT_FLOPPY_CMD;
579}
580
581static ide_startstop_t ide_transfer_pc(ide_drive_t *drive)
582{
583	struct ide_atapi_pc *uninitialized_var(pc);
584	ide_hwif_t *hwif = drive->hwif;
585	struct request *rq = hwif->rq;
586	ide_expiry_t *expiry;
587	unsigned int timeout;
588	int cmd_len;
589	ide_startstop_t startstop;
590	u8 ireason;
591
592	if (ide_wait_stat(&startstop, drive, ATA_DRQ, ATA_BUSY, WAIT_READY)) {
593		printk(KERN_ERR PFX "%s: Strange, packet command initiated yet "
594				"DRQ isn't asserted\n", drive->name);
595		return startstop;
596	}
597
598	if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) {
599		if (drive->dma)
600			drive->waiting_for_dma = 1;
601	}
602
603	if (dev_is_idecd(drive)) {
604		/* ATAPI commands get padded out to 12 bytes minimum */
605		cmd_len = COMMAND_SIZE(rq->cmd[0]);
606		if (cmd_len < ATAPI_MIN_CDB_BYTES)
607			cmd_len = ATAPI_MIN_CDB_BYTES;
608
609		timeout = rq->timeout;
610		expiry  = ide_cd_expiry;
611	} else {
612		pc = drive->pc;
613
614		cmd_len = ATAPI_MIN_CDB_BYTES;
615
616		/*
617		 * If necessary schedule the packet transfer to occur 'timeout'
618		 * milliseconds later in ide_delayed_transfer_pc() after the
619		 * device says it's ready for a packet.
620		 */
621		if (drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) {
622			timeout = drive->pc_delay;
623			expiry = &ide_delayed_transfer_pc;
624		} else {
625			timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
626							       : WAIT_TAPE_CMD;
627			expiry = NULL;
628		}
629
630		ireason = ide_read_ireason(drive);
631		if (drive->media == ide_tape)
632			ireason = ide_wait_ireason(drive, ireason);
633
634		if ((ireason & ATAPI_COD) == 0 || (ireason & ATAPI_IO)) {
635			printk(KERN_ERR PFX "%s: (IO,CoD) != (0,1) while "
636				"issuing a packet command\n", drive->name);
637
638			return ide_do_reset(drive);
639		}
640	}
641
642	hwif->expiry = expiry;
643
644	/* Set the interrupt routine */
645	ide_set_handler(drive,
646			(dev_is_idecd(drive) ? drive->irq_handler
647					     : ide_pc_intr),
648			timeout);
649
650	/* Send the actual packet */
651	if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0)
652		hwif->tp_ops->output_data(drive, NULL, rq->cmd, cmd_len);
653
654	/* Begin DMA, if necessary */
655	if (dev_is_idecd(drive)) {
656		if (drive->dma)
657			hwif->dma_ops->dma_start(drive);
658	} else {
659		if (pc->flags & PC_FLAG_DMA_OK) {
660			pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
661			hwif->dma_ops->dma_start(drive);
662		}
663	}
664
665	return ide_started;
666}
667
668ide_startstop_t ide_issue_pc(ide_drive_t *drive, struct ide_cmd *cmd)
669{
670	struct ide_atapi_pc *pc;
671	ide_hwif_t *hwif = drive->hwif;
672	ide_expiry_t *expiry = NULL;
673	struct request *rq = hwif->rq;
674	unsigned int timeout, bytes;
675	u16 bcount;
676	u8 valid_tf;
677	u8 drq_int = !!(drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT);
678
679	if (dev_is_idecd(drive)) {
680		valid_tf = IDE_VALID_NSECT | IDE_VALID_LBAL;
681		bcount = ide_cd_get_xferlen(rq);
682		expiry = ide_cd_expiry;
683		timeout = ATAPI_WAIT_PC;
684
685		if (drive->dma)
686			drive->dma = !ide_dma_prepare(drive, cmd);
687	} else {
688		pc = drive->pc;
689
690		valid_tf = IDE_VALID_DEVICE;
691		bytes = blk_rq_bytes(rq);
692		bcount = ((drive->media == ide_tape) ? bytes
693						     : min_t(unsigned int,
694							     bytes, 63 * 1024));
695
696		/* We haven't transferred any data yet */
697		rq->resid_len = bcount;
698
699		if (pc->flags & PC_FLAG_DMA_ERROR) {
700			pc->flags &= ~PC_FLAG_DMA_ERROR;
701			ide_dma_off(drive);
702		}
703
704		if (pc->flags & PC_FLAG_DMA_OK)
705			drive->dma = !ide_dma_prepare(drive, cmd);
706
707		if (!drive->dma)
708			pc->flags &= ~PC_FLAG_DMA_OK;
709
710		timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
711						       : WAIT_TAPE_CMD;
712	}
713
714	ide_init_packet_cmd(cmd, valid_tf, bcount, drive->dma);
715
716	(void)do_rw_taskfile(drive, cmd);
717
718	if (drq_int) {
719		if (drive->dma)
720			drive->waiting_for_dma = 0;
721		hwif->expiry = expiry;
722	}
723
724	ide_execute_command(drive, cmd, ide_transfer_pc, timeout);
725
726	return drq_int ? ide_started : ide_transfer_pc(drive);
727}
728EXPORT_SYMBOL_GPL(ide_issue_pc);
v4.17
  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);