/* -*-linux-c-*-
  
   * vendor-specific code for SCSI CD-ROM's goes here.
   *
   * This is needed becauce most of the new features (multisession and
   * the like) are too new to be included into the SCSI-II standard (to
   * be exact: there is'nt anything in my draft copy).
   *
   * Aug 1997: Ha! Got a SCSI-3 cdrom spec across my fingers. SCSI-3 does
   *           multisession using the READ TOC command (like SONY).
   *
   *           Rearranged stuff here: SCSI-3 is included allways, support
   *           for NEC/TOSHIBA/HP commands is optional.
   *
   *   Gerd Knorr <kraxel@cs.tu-berlin.de> 
   *
   * --------------------------------------------------------------------------
   *
   * support for XA/multisession-CD's
   * 
   *   - NEC:     Detection and support of multisession CD's.
   *     
   *   - TOSHIBA: Detection and support of multisession CD's.
   *              Some XA-Sector tweaking, required for older drives.
   *
   *   - SONY:    Detection and support of multisession CD's.
   *              added by Thomas Quinot <thomas@cuivre.freenix.fr>
   *
   *   - PIONEER, HITACHI, PLEXTOR, MATSHITA, TEAC, PHILIPS: known to
   *              work with SONY (SCSI3 now)  code.
   *
   *   - HP:      Much like SONY, but a little different... (Thomas)
   *              HP-Writers only ??? Maybe other CD-Writers work with this too ?
   *              HP 6020 writers now supported.
   */

  #include <linux/cdrom.h>
  #include <linux/errno.h>
  #include <linux/string.h>
  #include <linux/bcd.h>
  #include <linux/blkdev.h>

  #include <linux/slab.h>

  
  #include <scsi/scsi.h>
  #include <scsi/scsi_cmnd.h>
  #include <scsi/scsi_device.h>
  #include <scsi/scsi_host.h>
  #include <scsi/scsi_ioctl.h>
  
  #include "sr.h"
  
  #if 0
  #define DEBUG
  #endif
  
  /* here are some constants to sort the vendors into groups */
  
  #define VENDOR_SCSI3           1	/* default: scsi-3 mmc */
  
  #define VENDOR_NEC             2
  #define VENDOR_TOSHIBA         3
  #define VENDOR_WRITER          4	/* pre-scsi3 writers */
  
  #define VENDOR_TIMEOUT	30*HZ
  
  void sr_vendor_init(Scsi_CD *cd)
  {
  #ifndef CONFIG_BLK_DEV_SR_VENDOR
  	cd->vendor = VENDOR_SCSI3;
  #else

  	const char *vendor = cd->device->vendor;
  	const char *model = cd->device->model;

  	
  	/* default */
  	cd->vendor = VENDOR_SCSI3;
  	if (cd->readcd_known)
  		/* this is true for scsi3/mmc drives - no more checks */
  		return;
  
  	if (cd->device->type == TYPE_WORM) {
  		cd->vendor = VENDOR_WRITER;
  
  	} else if (!strncmp(vendor, "NEC", 3)) {
  		cd->vendor = VENDOR_NEC;
  		if (!strncmp(model, "CD-ROM DRIVE:25", 15) ||
  		    !strncmp(model, "CD-ROM DRIVE:36", 15) ||
  		    !strncmp(model, "CD-ROM DRIVE:83", 15) ||
  		    !strncmp(model, "CD-ROM DRIVE:84 ", 16)
  #if 0
  		/* my NEC 3x returns the read-raw data if a read-raw
  		   is followed by a read for the same sector - aeb */
  		    || !strncmp(model, "CD-ROM DRIVE:500", 16)
  #endif
  		    )
  			/* these can't handle multisession, may hang */
  			cd->cdi.mask |= CDC_MULTI_SESSION;
  
  	} else if (!strncmp(vendor, "TOSHIBA", 7)) {
  		cd->vendor = VENDOR_TOSHIBA;
  
  	}
  #endif
  }
  
  
  /* small handy function for switching block length using MODE SELECT,
   * used by sr_read_sector() */
  
  int sr_set_blocklength(Scsi_CD *cd, int blocklength)
  {
  	unsigned char *buffer;	/* the buffer for the ioctl */
  	struct packet_command cgc;
  	struct ccs_modesel_head *modesel;
  	int rc, density = 0;
  
  #ifdef CONFIG_BLK_DEV_SR_VENDOR
  	if (cd->vendor == VENDOR_TOSHIBA)
  		density = (blocklength > 2048) ? 0x81 : 0x83;
  #endif

  	buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);

  	if (!buffer)
  		return -ENOMEM;
  
  #ifdef DEBUG
  	printk("%s: MODE SELECT 0x%x/%d
  ", cd->cdi.name, density, blocklength);
  #endif
  	memset(&cgc, 0, sizeof(struct packet_command));
  	cgc.cmd[0] = MODE_SELECT;
  	cgc.cmd[1] = (1 << 4);
  	cgc.cmd[4] = 12;
  	modesel = (struct ccs_modesel_head *) buffer;
  	memset(modesel, 0, sizeof(*modesel));
  	modesel->block_desc_length = 0x08;
  	modesel->density = density;
  	modesel->block_length_med = (blocklength >> 8) & 0xff;
  	modesel->block_length_lo = blocklength & 0xff;
  	cgc.buffer = buffer;
  	cgc.buflen = sizeof(*modesel);
  	cgc.data_direction = DMA_TO_DEVICE;
  	cgc.timeout = VENDOR_TIMEOUT;
  	if (0 == (rc = sr_do_ioctl(cd, &cgc))) {
  		cd->device->sector_size = blocklength;
  	}
  #ifdef DEBUG
  	else
  		printk("%s: switching blocklength to %d bytes failed
  ",
  		       cd->cdi.name, blocklength);
  #endif
  	kfree(buffer);
  	return rc;
  }
  
  /* This function gets called after a media change. Checks if the CD is
     multisession, asks for offset etc. */
  
  int sr_cd_check(struct cdrom_device_info *cdi)
  {
  	Scsi_CD *cd = cdi->handle;
  	unsigned long sector;
  	unsigned char *buffer;	/* the buffer for the ioctl */
  	struct packet_command cgc;
  	int rc, no_multi;
  
  	if (cd->cdi.mask & CDC_MULTI_SESSION)
  		return 0;

  	buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);

  	if (!buffer)
  		return -ENOMEM;
  
  	sector = 0;		/* the multisession sector offset goes here  */
  	no_multi = 0;		/* flag: the drive can't handle multisession */
  	rc = 0;
  
  	memset(&cgc, 0, sizeof(struct packet_command));
  
  	switch (cd->vendor) {
  
  	case VENDOR_SCSI3:
  		cgc.cmd[0] = READ_TOC;
  		cgc.cmd[8] = 12;
  		cgc.cmd[9] = 0x40;
  		cgc.buffer = buffer;
  		cgc.buflen = 12;
  		cgc.quiet = 1;
  		cgc.data_direction = DMA_FROM_DEVICE;
  		cgc.timeout = VENDOR_TIMEOUT;
  		rc = sr_do_ioctl(cd, &cgc);
  		if (rc != 0)
  			break;
  		if ((buffer[0] << 8) + buffer[1] < 0x0a) {
  			printk(KERN_INFO "%s: Hmm, seems the drive "
  			   "doesn't support multisession CD's
  ", cd->cdi.name);
  			no_multi = 1;
  			break;
  		}
  		sector = buffer[11] + (buffer[10] << 8) +
  		    (buffer[9] << 16) + (buffer[8] << 24);
  		if (buffer[6] <= 1) {
  			/* ignore sector offsets from first track */
  			sector = 0;
  		}
  		break;
  
  #ifdef CONFIG_BLK_DEV_SR_VENDOR
  	case VENDOR_NEC:{
  			unsigned long min, sec, frame;
  			cgc.cmd[0] = 0xde;
  			cgc.cmd[1] = 0x03;
  			cgc.cmd[2] = 0xb0;
  			cgc.buffer = buffer;
  			cgc.buflen = 0x16;
  			cgc.quiet = 1;
  			cgc.data_direction = DMA_FROM_DEVICE;
  			cgc.timeout = VENDOR_TIMEOUT;
  			rc = sr_do_ioctl(cd, &cgc);
  			if (rc != 0)
  				break;
  			if (buffer[14] != 0 && buffer[14] != 0xb0) {
  				printk(KERN_INFO "%s: Hmm, seems the cdrom "
  				       "doesn't support multisession CD's
  ",
  				       cd->cdi.name);
  				no_multi = 1;
  				break;
  			}

  			min = bcd2bin(buffer[15]);
  			sec = bcd2bin(buffer[16]);
  			frame = bcd2bin(buffer[17]);

  			sector = min * CD_SECS * CD_FRAMES + sec * CD_FRAMES + frame;
  			break;
  		}
  
  	case VENDOR_TOSHIBA:{
  			unsigned long min, sec, frame;
  
  			/* we request some disc information (is it a XA-CD ?,
  			 * where starts the last session ?) */
  			cgc.cmd[0] = 0xc7;
  			cgc.cmd[1] = 0x03;
  			cgc.buffer = buffer;
  			cgc.buflen = 4;
  			cgc.quiet = 1;
  			cgc.data_direction = DMA_FROM_DEVICE;
  			cgc.timeout = VENDOR_TIMEOUT;
  			rc = sr_do_ioctl(cd, &cgc);
  			if (rc == -EINVAL) {
  				printk(KERN_INFO "%s: Hmm, seems the drive "
  				       "doesn't support multisession CD's
  ",
  				       cd->cdi.name);
  				no_multi = 1;
  				break;
  			}
  			if (rc != 0)
  				break;

  			min = bcd2bin(buffer[1]);
  			sec = bcd2bin(buffer[2]);
  			frame = bcd2bin(buffer[3]);

  			sector = min * CD_SECS * CD_FRAMES + sec * CD_FRAMES + frame;
  			if (sector)
  				sector -= CD_MSF_OFFSET;
  			sr_set_blocklength(cd, 2048);
  			break;
  		}
  
  	case VENDOR_WRITER:
  		cgc.cmd[0] = READ_TOC;
  		cgc.cmd[8] = 0x04;
  		cgc.cmd[9] = 0x40;
  		cgc.buffer = buffer;
  		cgc.buflen = 0x04;
  		cgc.quiet = 1;
  		cgc.data_direction = DMA_FROM_DEVICE;
  		cgc.timeout = VENDOR_TIMEOUT;
  		rc = sr_do_ioctl(cd, &cgc);
  		if (rc != 0) {
  			break;
  		}
  		if ((rc = buffer[2]) == 0) {
  			printk(KERN_WARNING
  			       "%s: No finished session
  ", cd->cdi.name);
  			break;
  		}
  		cgc.cmd[0] = READ_TOC;	/* Read TOC */
  		cgc.cmd[6] = rc & 0x7f;	/* number of last session */
  		cgc.cmd[8] = 0x0c;
  		cgc.cmd[9] = 0x40;
  		cgc.buffer = buffer;
  		cgc.buflen = 12;
  		cgc.quiet = 1;
  		cgc.data_direction = DMA_FROM_DEVICE;
  		cgc.timeout = VENDOR_TIMEOUT;
  		rc = sr_do_ioctl(cd, &cgc);
  		if (rc != 0) {
  			break;
  		}
  		sector = buffer[11] + (buffer[10] << 8) +
  		    (buffer[9] << 16) + (buffer[8] << 24);
  		break;
  #endif				/* CONFIG_BLK_DEV_SR_VENDOR */
  
  	default:
  		/* should not happen */
  		printk(KERN_WARNING
  		   "%s: unknown vendor code (%i), not initialized ?
  ",
  		       cd->cdi.name, cd->vendor);
  		sector = 0;
  		no_multi = 1;
  		break;
  	}
  	cd->ms_offset = sector;
  	cd->xa_flag = 0;
  	if (CDS_AUDIO != sr_disk_status(cdi) && 1 == sr_is_xa(cd))
  		cd->xa_flag = 1;
  
  	if (2048 != cd->device->sector_size) {
  		sr_set_blocklength(cd, 2048);
  	}
  	if (no_multi)
  		cdi->mask |= CDC_MULTI_SESSION;
  
  #ifdef DEBUG
  	if (sector)
  		printk(KERN_DEBUG "%s: multisession offset=%lu
  ",
  		       cd->cdi.name, sector);
  #endif
  	kfree(buffer);
  	return rc;
  }