datafab.c

LINUX下USB驱动程序的开发

			return USB_STOR_TRANSPORT_ERROR;
		}

		sectors -= thistime;
		sector  += thistime;

		if (use_sg) {
			kfree(buffer);
		} else {
			src += len;
		}

		totallen -= len;
	} while (totallen > 0);

	return USB_STOR_TRANSPORT_GOOD;
}


static int datafab_determine_lun(struct us_data *us,
				 struct datafab_info *info)
{
	// dual-slot readers can be thought of as dual-LUN devices.  we need to
	// determine which card slot is being used.  we'll send an IDENTIFY DEVICE
	// command and see which LUN responds...
	//
	// there might be a better way of doing this?
	//
	unsigned char command[8] = { 0, 1, 0, 0, 0, 0xa0, 0xec, 1 };
	unsigned char buf[512];
	int count = 0, rc;

	if (!us || !info)
		return USB_STOR_TRANSPORT_ERROR;

	US_DEBUGP("datafab_determine_lun:  locating...\n");

	// we'll try 10 times before giving up...
	//
	while (count++ < 10) {
		command[5] = 0xa0;

		rc = datafab_bulk_write(us, command, 8);
		if (rc != USB_STOR_TRANSPORT_GOOD) 
			return rc;

		rc = datafab_bulk_read(us, buf, sizeof(buf));
		if (rc == USB_STOR_TRANSPORT_GOOD) {
			info->lun = 0;
			return USB_STOR_TRANSPORT_GOOD;
		}

		command[5] = 0xb0;

		rc = datafab_bulk_write(us, command, 8);
		if (rc != USB_STOR_TRANSPORT_GOOD) 
			return rc;

		rc = datafab_bulk_read(us, buf, sizeof(buf));
		if (rc == USB_STOR_TRANSPORT_GOOD) {
			info->lun = 1;
			return USB_STOR_TRANSPORT_GOOD;
		}

                wait_ms(20);
	}

	return USB_STOR_TRANSPORT_FAILED;
}

static int datafab_id_device(struct us_data *us,
			     struct datafab_info *info)
{
	// this is a variation of the ATA "IDENTIFY DEVICE" command...according
	// to the ATA spec, 'Sector Count' isn't used but the Windows driver
	// sets this bit so we do too...
	//
	unsigned char command[8] = { 0, 1, 0, 0, 0, 0xa0, 0xec, 1 };
	unsigned char reply[512];
	int rc;

	if (!us || !info)
		return USB_STOR_TRANSPORT_ERROR;

	if (info->lun == -1) {
		rc = datafab_determine_lun(us, info);
		if (rc != USB_STOR_TRANSPORT_GOOD)
			return rc;
	}

	command[5] += (info->lun << 4);

	rc = datafab_bulk_write(us, command, 8);
	if (rc != USB_STOR_TRANSPORT_GOOD) 
		return rc;

	// we'll go ahead and extract the media capacity while we're here...
	//
	rc = datafab_bulk_read(us, reply, sizeof(reply));
	if (rc == USB_STOR_TRANSPORT_GOOD) {
		// capacity is at word offset 57-58
		//
		info->sectors = ((u32)(reply[117]) << 24) | 
				((u32)(reply[116]) << 16) |
				((u32)(reply[115]) <<  8) | 
				((u32)(reply[114])      );
	}
		
	return rc;
}


static int datafab_handle_mode_sense(struct us_data *us,
				     Scsi_Cmnd * srb, 
		                     unsigned char *ptr,
				     int sense_6)
{
	unsigned char mode_param_header[8] = {
		0, 0, 0, 0, 0, 0, 0, 0
	};
	unsigned char rw_err_page[12] = {
		0x1, 0xA, 0x21, 1, 0, 0, 0, 0, 1, 0, 0, 0
	};
	unsigned char cache_page[12] = {
		0x8, 0xA, 0x1, 0, 0, 0, 0, 0, 0, 0, 0, 0
	};
	unsigned char rbac_page[12] = {
		0x1B, 0xA, 0, 0x81, 0, 0, 0, 0, 0, 0, 0, 0
	};
	unsigned char timer_page[8] = {
		0x1C, 0x6, 0, 0, 0, 0
	};
	unsigned char pc, page_code;
	unsigned short total_len = 0;
	unsigned short param_len, i = 0;

	// most of this stuff is just a hack to get things working.  the
	// datafab reader doesn't present a SCSI interface so we
	// fudge the SCSI commands...
	//
        
	if (sense_6)
		param_len = srb->cmnd[4];
	else
		param_len = ((u16) (srb->cmnd[7]) >> 8) | ((u16) (srb->cmnd[8]));

	pc = srb->cmnd[2] >> 6;
	page_code = srb->cmnd[2] & 0x3F;

	switch (pc) {
	   case 0x0:
		US_DEBUGP("datafab_handle_mode_sense:  Current values\n");
		break;
	   case 0x1:
		US_DEBUGP("datafab_handle_mode_sense:  Changeable values\n");
		break;
	   case 0x2:
		US_DEBUGP("datafab_handle_mode_sense:  Default values\n");
		break;
	   case 0x3:
		US_DEBUGP("datafab_handle_mode_sense:  Saves values\n");
		break;
	}

	mode_param_header[3] = 0x80;	// write enable

	switch (page_code) {
	   case 0x0:
		// vendor-specific mode
		return USB_STOR_TRANSPORT_ERROR;

	   case 0x1:
		total_len = sizeof(rw_err_page);
		mode_param_header[0] = total_len >> 8;
		mode_param_header[1] = total_len & 0xFF;
		mode_param_header[3] = 0x00;	// WP enable: 0x80

		memcpy(ptr, mode_param_header, sizeof(mode_param_header));
		i += sizeof(mode_param_header);
		memcpy(ptr + i, rw_err_page, sizeof(rw_err_page));
		break;

	   case 0x8:
		total_len = sizeof(cache_page);
		mode_param_header[0] = total_len >> 8;
		mode_param_header[1] = total_len & 0xFF;
		mode_param_header[3] = 0x00;	// WP enable: 0x80

		memcpy(ptr, mode_param_header, sizeof(mode_param_header));
		i += sizeof(mode_param_header);
		memcpy(ptr + i, cache_page, sizeof(cache_page));
		break;

	   case 0x1B:
		total_len = sizeof(rbac_page);
		mode_param_header[0] = total_len >> 8;
		mode_param_header[1] = total_len & 0xFF;
		mode_param_header[3] = 0x00;	// WP enable: 0x80

		memcpy(ptr, mode_param_header, sizeof(mode_param_header));
		i += sizeof(mode_param_header);
		memcpy(ptr + i, rbac_page, sizeof(rbac_page));
		break;

	   case 0x1C:
		total_len = sizeof(timer_page);
		mode_param_header[0] = total_len >> 8;
		mode_param_header[1] = total_len & 0xFF;
		mode_param_header[3] = 0x00;	// WP enable: 0x80

		memcpy(ptr, mode_param_header, sizeof(mode_param_header));
		i += sizeof(mode_param_header);
		memcpy(ptr + i, timer_page, sizeof(timer_page));
		break;

	   case 0x3F:		// retrieve all pages
		total_len = sizeof(timer_page) + sizeof(rbac_page) +
		    sizeof(cache_page) + sizeof(rw_err_page);
		mode_param_header[0] = total_len >> 8;
		mode_param_header[1] = total_len & 0xFF;
		mode_param_header[3] = 0x00;	// WP enable

		memcpy(ptr, mode_param_header, sizeof(mode_param_header));
		i += sizeof(mode_param_header);
		memcpy(ptr + i, timer_page, sizeof(timer_page));
		i += sizeof(timer_page);
		memcpy(ptr + i, rbac_page, sizeof(rbac_page));
		i += sizeof(rbac_page);
		memcpy(ptr + i, cache_page, sizeof(cache_page));
		i += sizeof(cache_page);
		memcpy(ptr + i, rw_err_page, sizeof(rw_err_page));
		break;
	}

	return USB_STOR_TRANSPORT_GOOD;
}

void datafab_info_destructor(void *extra)
{
	// this routine is a placeholder...
	// currently, we don't allocate any extra memory so we're okay
}


// Transport for the Datafab MDCFE-B
//
int datafab_transport(Scsi_Cmnd * srb, struct us_data *us)
{
	struct datafab_info *info;
	int rc;
	unsigned long block, blocks;
	unsigned char *ptr = NULL;
	unsigned char inquiry_reply[36] = {
		0x00, 0x80, 0x00, 0x01, 0x1F, 0x00, 0x00, 0x00
	};

	if (!us->extra) {
		us->extra = kmalloc(sizeof(struct datafab_info), GFP_NOIO);
		if (!us->extra) {
			US_DEBUGP("datafab_transport:  Gah! Can't allocate storage for Datafab info struct!\n");
			return USB_STOR_TRANSPORT_ERROR;
		}
		memset(us->extra, 0, sizeof(struct datafab_info));
		us->extra_destructor = datafab_info_destructor;
  		((struct datafab_info *)us->extra)->lun = -1;
	}

	info = (struct datafab_info *) (us->extra);
	ptr = (unsigned char *) srb->request_buffer;

	if (srb->cmnd[0] == INQUIRY) {
		US_DEBUGP("datafab_transport:  INQUIRY.  Returning bogus response");
		memset( inquiry_reply + 8, 0, 28 );
		fill_inquiry_response(us, inquiry_reply, 36);
		return USB_STOR_TRANSPORT_GOOD;
	}

	if (srb->cmnd[0] == READ_CAPACITY) {
		unsigned int max_sector;

		info->ssize = 0x200;  // hard coded 512 byte sectors as per ATA spec
		rc = datafab_id_device(us, info);
		if (rc != USB_STOR_TRANSPORT_GOOD)
			return rc;

		US_DEBUGP("datafab_transport:  READ_CAPACITY:  "
			  "%ld sectors, %ld bytes per sector\n",
			  info->sectors, info->ssize);

		// build the reply
		//
		max_sector = info->sectors - 1;
		ptr[0] = (max_sector >> 24) & 0xFF;
		ptr[1] = (max_sector >> 16) & 0xFF;
		ptr[2] = (max_sector >> 8) & 0xFF;
		ptr[3] = (max_sector) & 0xFF;

		ptr[4] = (info->ssize >> 24) & 0xFF;
		ptr[5] = (info->ssize >> 16) & 0xFF;
		ptr[6] = (info->ssize >> 8) & 0xFF;
		ptr[7] = (info->ssize) & 0xFF;

		return USB_STOR_TRANSPORT_GOOD;
	}

	if (srb->cmnd[0] == MODE_SELECT_10) {
		US_DEBUGP("datafab_transport:  Gah! MODE_SELECT_10.\n");
		return USB_STOR_TRANSPORT_ERROR;
	}

	// don't bother implementing READ_6 or WRITE_6.  Just set MODE_XLATE and
	// let the usb storage code convert to READ_10/WRITE_10
	//
	if (srb->cmnd[0] == READ_10) {
		block = ((u32)(srb->cmnd[2]) << 24) | ((u32)(srb->cmnd[3]) << 16) |
		        ((u32)(srb->cmnd[4]) <<  8) | ((u32)(srb->cmnd[5]));

		blocks = ((u32)(srb->cmnd[7]) << 8) | ((u32)(srb->cmnd[8]));

		US_DEBUGP("datafab_transport:  READ_10: read block 0x%04lx  count %ld\n", block, blocks);
		return datafab_read_data(us, info, block, blocks, ptr, srb->use_sg);
	}

	if (srb->cmnd[0] == READ_12) {
		// we'll probably never see a READ_12 but we'll do it anyway...
		//
		block = ((u32)(srb->cmnd[2]) << 24) | ((u32)(srb->cmnd[3]) << 16) |
		        ((u32)(srb->cmnd[4]) <<  8) | ((u32)(srb->cmnd[5]));

		blocks = ((u32)(srb->cmnd[6]) << 24) | ((u32)(srb->cmnd[7]) << 16) |
		         ((u32)(srb->cmnd[8]) <<  8) | ((u32)(srb->cmnd[9]));

		US_DEBUGP("datafab_transport:  READ_12: read block 0x%04lx  count %ld\n", block, blocks);
		return datafab_read_data(us, info, block, blocks, ptr, srb->use_sg);
	}

	if (srb->cmnd[0] == WRITE_10) {
		block = ((u32)(srb->cmnd[2]) << 24) | ((u32)(srb->cmnd[3]) << 16) |
		        ((u32)(srb->cmnd[4]) <<  8) | ((u32)(srb->cmnd[5]));

		blocks = ((u32)(srb->cmnd[7]) << 8) | ((u32)(srb->cmnd[8]));

		US_DEBUGP("datafab_transport:  WRITE_10: write block 0x%04lx  count %ld\n", block, blocks);
		return datafab_write_data(us, info, block, blocks, ptr, srb->use_sg);
	}

	if (srb->cmnd[0] == WRITE_12) {
		// we'll probably never see a WRITE_12 but we'll do it anyway...
		//
		block = ((u32)(srb->cmnd[2]) << 24) | ((u32)(srb->cmnd[3]) << 16) |
		        ((u32)(srb->cmnd[4]) <<  8) | ((u32)(srb->cmnd[5]));

		blocks = ((u32)(srb->cmnd[6]) << 24) | ((u32)(srb->cmnd[7]) << 16) |
		         ((u32)(srb->cmnd[8]) <<  8) | ((u32)(srb->cmnd[9]));

		US_DEBUGP("datafab_transport:  WRITE_12: write block 0x%04lx  count %ld\n", block, blocks);
		return datafab_write_data(us, info, block, blocks, ptr, srb->use_sg);
	}

	if (srb->cmnd[0] == TEST_UNIT_READY) {
		US_DEBUGP("datafab_transport:  TEST_UNIT_READY.\n");
		return datafab_id_device(us, info);
	}

	if (srb->cmnd[0] == REQUEST_SENSE) {
		US_DEBUGP("datafab_transport:  REQUEST_SENSE.  Returning faked response\n");

		// this response is pretty bogus right now.  eventually if necessary
		// we can set the correct sense data.  so far though it hasn't been
		// necessary
		//
		ptr[0] = 0xF0;
		ptr[2] = info->sense_key;
		ptr[7] = 11;
		ptr[12] = info->sense_asc;
		ptr[13] = info->sense_ascq;

		return USB_STOR_TRANSPORT_GOOD;
	}

	if (srb->cmnd[0] == MODE_SENSE) {
		US_DEBUGP("datafab_transport:  MODE_SENSE_6 detected\n");
		return datafab_handle_mode_sense(us, srb, ptr, TRUE);
	}

	if (srb->cmnd[0] == MODE_SENSE_10) {
		US_DEBUGP("datafab_transport:  MODE_SENSE_10 detected\n");
		return datafab_handle_mode_sense(us, srb, ptr, FALSE);
	}

	if (srb->cmnd[0] == ALLOW_MEDIUM_REMOVAL) {
		// sure.  whatever.  not like we can stop the user from
		// popping the media out of the device (no locking doors, etc)
		//
		return USB_STOR_TRANSPORT_GOOD;
	}

	if (srb->cmnd[0] == START_STOP) {
		/* this is used by sd.c'check_scsidisk_media_change to detect
		   media change */
		US_DEBUGP("datafab_transport:  START_STOP.\n");
		/* the first datafab_id_device after a media change returns
		   an error (determined experimentally) */
		rc = datafab_id_device(us, info);
		if (rc == USB_STOR_TRANSPORT_GOOD) {
			info->sense_key = NO_SENSE;
			srb->result = SUCCESS;
		} else {
			info->sense_key = UNIT_ATTENTION;
			srb->result = CHECK_CONDITION;
		}
		return rc;
        }

	US_DEBUGP("datafab_transport:  Gah! Unknown command: %d (0x%x)\n", srb->cmnd[0], srb->cmnd[0]);
	return USB_STOR_TRANSPORT_ERROR;
}