ide-cd.c

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					}
					printk ("%s: DSC timeout\n", drive->name);
				}
				CDROM_CONFIG_FLAGS(drive)->seeking = 0;
			}
			if (IDE_LARGE_SEEK(info->last_block, block, IDECD_SEEK_THRESHOLD) && drive->dsc_overlap)
				action = cdrom_start_seek (drive, block);
			else {
				if (rq->cmd == READ)
					action = cdrom_start_read(drive, block);
				else
					action = cdrom_start_write(drive);
			}
			info->last_block = block;
			return action;
		}

		case PACKET_COMMAND:
		case REQUEST_SENSE_COMMAND: {
			return cdrom_do_packet_command(drive);
		}

		case RESET_DRIVE_COMMAND: {
			cdrom_end_request(1, drive);
			return ide_do_reset(drive);
		}

		default: {
			printk("ide-cd: bad cmd %d\n", rq->cmd);
			cdrom_end_request(0, drive);
			return ide_stopped;
		}
	}
}



/****************************************************************************
 * Ioctl handling.
 *
 * Routines which queue packet commands take as a final argument a pointer
 * to a request_sense struct.  If execution of the command results
 * in an error with a CHECK CONDITION status, this structure will be filled
 * with the results of the subsequent request sense command.  The pointer
 * can also be NULL, in which case no sense information is returned.
 */

#if ! STANDARD_ATAPI
static inline
int bin2bcd (int x)
{
	return (x%10) | ((x/10) << 4);
}


static inline
int bcd2bin (int x)
{
	return (x >> 4) * 10 + (x & 0x0f);
}

static
void msf_from_bcd (struct atapi_msf *msf)
{
	msf->minute = bcd2bin (msf->minute);
	msf->second = bcd2bin (msf->second);
	msf->frame  = bcd2bin (msf->frame);
}

#endif /* not STANDARD_ATAPI */


static inline
void lba_to_msf (int lba, byte *m, byte *s, byte *f)
{
	lba += CD_MSF_OFFSET;
	lba &= 0xffffff;  /* negative lbas use only 24 bits */
	*m = lba / (CD_SECS * CD_FRAMES);
	lba %= (CD_SECS * CD_FRAMES);
	*s = lba / CD_FRAMES;
	*f = lba % CD_FRAMES;
}


static inline
int msf_to_lba (byte m, byte s, byte f)
{
	return (((m * CD_SECS) + s) * CD_FRAMES + f) - CD_MSF_OFFSET;
}

static int cdrom_check_status(ide_drive_t *drive, struct request_sense *sense)
{
	struct packet_command pc;
	struct cdrom_info *info = drive->driver_data;
	struct cdrom_device_info *cdi = &info->devinfo;

	memset(&pc, 0, sizeof(pc));
	pc.sense = sense;

	pc.c[0] = GPCMD_TEST_UNIT_READY;

#if ! STANDARD_ATAPI
        /* the Sanyo 3 CD changer uses byte 7 of TEST_UNIT_READY to 
           switch CDs instead of supporting the LOAD_UNLOAD opcode   */

        pc.c[7] = cdi->sanyo_slot % 3;
#endif /* not STANDARD_ATAPI */

	return cdrom_queue_packet_command(drive, &pc);
}


/* Lock the door if LOCKFLAG is nonzero; unlock it otherwise. */
static int
cdrom_lockdoor(ide_drive_t *drive, int lockflag, struct request_sense *sense)
{
	struct request_sense my_sense;
	struct packet_command pc;
	int stat;

	if (sense == NULL)
		sense = &my_sense;

	/* If the drive cannot lock the door, just pretend. */
	if (CDROM_CONFIG_FLAGS(drive)->no_doorlock) {
		stat = 0;
	} else {
		memset(&pc, 0, sizeof(pc));
		pc.sense = sense;
		pc.c[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
		pc.c[4] = lockflag ? 1 : 0;
		stat = cdrom_queue_packet_command (drive, &pc);
	}

	/* If we got an illegal field error, the drive
	   probably cannot lock the door. */
	if (stat != 0 &&
	    sense->sense_key == ILLEGAL_REQUEST &&
	    (sense->asc == 0x24 || sense->asc == 0x20)) {
		printk ("%s: door locking not supported\n",
			drive->name);
		CDROM_CONFIG_FLAGS (drive)->no_doorlock = 1;
		stat = 0;
	}
	
	/* no medium, that's alright. */
	if (stat != 0 && sense->sense_key == NOT_READY && sense->asc == 0x3a)
		stat = 0;

	if (stat == 0)
		CDROM_STATE_FLAGS (drive)->door_locked = lockflag;

	return stat;
}


/* Eject the disk if EJECTFLAG is 0.
   If EJECTFLAG is 1, try to reload the disk. */
static int cdrom_eject(ide_drive_t *drive, int ejectflag,
		       struct request_sense *sense)
{
	struct packet_command pc;

	if (CDROM_CONFIG_FLAGS(drive)->no_eject && !ejectflag)
		return -EDRIVE_CANT_DO_THIS;
	
	/* reload fails on some drives, if the tray is locked */
	if (CDROM_STATE_FLAGS(drive)->door_locked && ejectflag)
		return 0;

	memset(&pc, 0, sizeof (pc));
	pc.sense = sense;

	pc.c[0] = GPCMD_START_STOP_UNIT;
	pc.c[4] = 0x02 + (ejectflag != 0);
	return cdrom_queue_packet_command (drive, &pc);
}

static int cdrom_read_capacity(ide_drive_t *drive, unsigned *capacity,
			       struct request_sense *sense)
{
	struct {
		__u32 lba;
		__u32 blocklen;
	} capbuf;

	int stat;
	struct packet_command pc;

	memset(&pc, 0, sizeof(pc));
	pc.sense = sense;

	pc.c[0] = GPCMD_READ_CDVD_CAPACITY;
	pc.buffer = (char *)&capbuf;
	pc.buflen = sizeof(capbuf);

	stat = cdrom_queue_packet_command(drive, &pc);
	if (stat == 0)
		*capacity = 1 + be32_to_cpu(capbuf.lba);

	return stat;
}

static int cdrom_read_tocentry(ide_drive_t *drive, int trackno, int msf_flag,
				int format, char *buf, int buflen,
				struct request_sense *sense)
{
	struct packet_command pc;

	memset(&pc, 0, sizeof(pc));
	pc.sense = sense;

	pc.buffer =  buf;
	pc.buflen = buflen;
	pc.c[0] = GPCMD_READ_TOC_PMA_ATIP;
	pc.c[6] = trackno;
	pc.c[7] = (buflen >> 8);
	pc.c[8] = (buflen & 0xff);
	pc.c[9] = (format << 6);

	if (msf_flag)
		pc.c[1] = 2;

	return cdrom_queue_packet_command (drive, &pc);
}


/* Try to read the entire TOC for the disk into our internal buffer. */
static int cdrom_read_toc(ide_drive_t *drive, struct request_sense *sense)
{
	int minor, stat, ntracks, i;
	kdev_t dev;
	struct cdrom_info *info = drive->driver_data;
	struct atapi_toc *toc = info->toc;
	struct {
		struct atapi_toc_header hdr;
		struct atapi_toc_entry  ent;
	} ms_tmp;

	if (toc == NULL) {
		/* Try to allocate space. */
		toc = (struct atapi_toc *) kmalloc (sizeof (struct atapi_toc),
						    GFP_KERNEL);
		info->toc = toc;
		if (toc == NULL) {
			printk ("%s: No cdrom TOC buffer!\n", drive->name);
			return -ENOMEM;
		}
	}

	/* Check to see if the existing data is still valid.
	   If it is, just return. */
	(void) cdrom_check_status(drive, sense);

	if (CDROM_STATE_FLAGS(drive)->toc_valid)
		return 0;

	/* First read just the header, so we know how long the TOC is. */
	stat = cdrom_read_tocentry(drive, 0, 1, 0, (char *) &toc->hdr,
				    sizeof(struct atapi_toc_header), sense);
	if (stat) return stat;

#if ! STANDARD_ATAPI
	if (CDROM_CONFIG_FLAGS (drive)->toctracks_as_bcd) {
		toc->hdr.first_track = bcd2bin (toc->hdr.first_track);
		toc->hdr.last_track  = bcd2bin (toc->hdr.last_track);
	}
#endif  /* not STANDARD_ATAPI */

	ntracks = toc->hdr.last_track - toc->hdr.first_track + 1;
	if (ntracks <= 0)
		return -EIO;
	if (ntracks > MAX_TRACKS)
		ntracks = MAX_TRACKS;

	/* Now read the whole schmeer. */
	stat = cdrom_read_tocentry(drive, toc->hdr.first_track, 1, 0,
				  (char *)&toc->hdr,
				   sizeof(struct atapi_toc_header) +
				   (ntracks + 1) *
				   sizeof(struct atapi_toc_entry), sense);

	if (stat && toc->hdr.first_track > 1) {
		/* Cds with CDI tracks only don't have any TOC entries,
		   despite of this the returned values are
		   first_track == last_track = number of CDI tracks + 1,
		   so that this case is indistinguishable from the same
		   layout plus an additional audio track.
		   If we get an error for the regular case, we assume
		   a CDI without additional audio tracks. In this case
		   the readable TOC is empty (CDI tracks are not included)
		   and only holds the Leadout entry. Heiko Ei遞eldt */
		ntracks = 0;
		stat = cdrom_read_tocentry(drive, CDROM_LEADOUT, 1, 0,
					   (char *)&toc->hdr,
					   sizeof(struct atapi_toc_header) +
					   (ntracks + 1) *
					   sizeof(struct atapi_toc_entry),
					   sense);
		if (stat) {
			return stat;
		}
#if ! STANDARD_ATAPI
		if (CDROM_CONFIG_FLAGS (drive)->toctracks_as_bcd) {
			toc->hdr.first_track = bin2bcd(CDROM_LEADOUT);
			toc->hdr.last_track = bin2bcd(CDROM_LEADOUT);
		} else
#endif  /* not STANDARD_ATAPI */
		{
			toc->hdr.first_track = CDROM_LEADOUT;
			toc->hdr.last_track = CDROM_LEADOUT;
		}
	}

	if (stat)
		return stat;

	toc->hdr.toc_length = ntohs (toc->hdr.toc_length);

#if ! STANDARD_ATAPI
	if (CDROM_CONFIG_FLAGS (drive)->toctracks_as_bcd) {
		toc->hdr.first_track = bcd2bin (toc->hdr.first_track);
		toc->hdr.last_track  = bcd2bin (toc->hdr.last_track);
	}
#endif  /* not STANDARD_ATAPI */

	for (i=0; i<=ntracks; i++) {
#if ! STANDARD_ATAPI
		if (CDROM_CONFIG_FLAGS (drive)->tocaddr_as_bcd) {
			if (CDROM_CONFIG_FLAGS (drive)->toctracks_as_bcd)
				toc->ent[i].track = bcd2bin (toc->ent[i].track);
			msf_from_bcd (&toc->ent[i].addr.msf);
		}
#endif  /* not STANDARD_ATAPI */
		toc->ent[i].addr.lba = msf_to_lba (toc->ent[i].addr.msf.minute,
						   toc->ent[i].addr.msf.second,
						   toc->ent[i].addr.msf.frame);
	}

	/* Read the multisession information. */
	if (toc->hdr.first_track != CDROM_LEADOUT) {
		/* Read the multisession information. */
		stat = cdrom_read_tocentry(drive, 0, 1, 1, (char *)&ms_tmp,
					   sizeof(ms_tmp), sense);
		if (stat) return stat;
	} else {
		ms_tmp.ent.addr.msf.minute = 0;
		ms_tmp.ent.addr.msf.second = 2;
		ms_tmp.ent.addr.msf.frame  = 0;
		ms_tmp.hdr.first_track = ms_tmp.hdr.last_track = CDROM_LEADOUT;
	}

#if ! STANDARD_ATAPI
	if (CDROM_CONFIG_FLAGS (drive)->tocaddr_as_bcd)
		msf_from_bcd (&ms_tmp.ent.addr.msf);
#endif  /* not STANDARD_ATAPI */

	toc->last_session_lba = msf_to_lba (ms_tmp.ent.addr.msf.minute,
					    ms_tmp.ent.addr.msf.second,
					    ms_tmp.ent.addr.msf.frame);

	toc->xa_flag = (ms_tmp.hdr.first_track != ms_tmp.hdr.last_track);

	/* Now try to get the total cdrom capacity. */
	minor = (drive->select.b.unit) << PARTN_BITS;
	dev = MKDEV(HWIF(drive)->major, minor);
	stat = cdrom_get_last_written(dev, (long *)&toc->capacity);
	if (stat)
		stat = cdrom_read_capacity(drive, &toc->capacity, sense);
	if (stat)
		toc->capacity = 0x1fffff;

	HWIF(drive)->gd->sizes[drive->select.b.unit << PARTN_BITS] = (toc->capacity * SECTORS_PER_FRAME) >> (BLOCK_SIZE_BITS - 9);
	drive->part[0].nr_sects = toc->capacity * SECTORS_PER_FRAME;

	/* Remember that we've read this stuff. */
	CDROM_STATE_FLAGS (drive)->toc_valid = 1;

	return 0;
}


static int cdrom_read_subchannel(ide_drive_t *drive, int format, char *buf,
				 int buflen, struct request_sense *sense)
{
	struct packet_command pc;

	memset(&pc, 0, sizeof(pc));
	pc.sense = sense;

	pc.buffer = buf;
	pc.buflen = buflen;
	pc.c[0] = GPCMD_READ_SUBCHANNEL;
	pc.c[1] = 2;     /* MSF addressing */
	pc.c[2] = 0x40;  /* request subQ data */
	pc.c[3] = format;
	pc.c[7] = (buflen >> 8);
	pc.c[8] = (buflen & 0xff);
	return cdrom_queue_packet_command(drive, &pc);
}

/* ATAPI cdrom drives are free to select the speed you request or any slower
   rate :-( Requesting too fast a speed will _not_ produce an error. */
static int cdrom_select_spee