xref: /openbmc/linux/drivers/usb/image/microtek.c (revision a09d2831)
1 /* Driver for Microtek Scanmaker X6 USB scanner, and possibly others.
2  *
3  * (C) Copyright 2000 John Fremlin <vii@penguinpowered.com>
4  * (C) Copyright 2000 Oliver Neukum <Oliver.Neukum@lrz.uni-muenchen.de>
5  *
6  * Parts shamelessly stolen from usb-storage and copyright by their
7  * authors. Thanks to Matt Dharm for giving us permission!
8  *
9  * This driver implements a SCSI host controller driver and a USB
10  * device driver. To avoid confusion, all the USB related stuff is
11  * prefixed by mts_usb_ and all the SCSI stuff by mts_scsi_.
12  *
13  * Microtek (www.microtek.com) did not release the specifications for
14  * their USB protocol to us, so we had to reverse engineer them. We
15  * don't know for which models they are valid.
16  *
17  * The X6 USB has three bulk endpoints, one output (0x1) down which
18  * commands and outgoing data are sent, and two input: 0x82 from which
19  * normal data is read from the scanner (in packets of maximum 32
20  * bytes) and from which the status byte is read, and 0x83 from which
21  * the results of a scan (or preview) are read in up to 64 * 1024 byte
22  * chunks by the Windows driver. We don't know how much it is possible
23  * to read at a time from 0x83.
24  *
25  * It seems possible to read (with URB transfers) everything from 0x82
26  * in one go, without bothering to read in 32 byte chunks.
27  *
28  * There seems to be an optimisation of a further READ implicit if
29  * you simply read from 0x83.
30  *
31  * Guessed protocol:
32  *
33  *	Send raw SCSI command to EP 0x1
34  *
35  *	If there is data to receive:
36  *		If the command was READ datatype=image:
37  *			Read a lot of data from EP 0x83
38  *		Else:
39  *			Read data from EP 0x82
40  *	Else:
41  *		If there is data to transmit:
42  *			Write it to EP 0x1
43  *
44  *	Read status byte from EP 0x82
45  *
46  * References:
47  *
48  * The SCSI command set for the scanner is available from
49  *	ftp://ftp.microtek.com/microtek/devpack/
50  *
51  * Microtek NV sent us a more up to date version of the document. If
52  * you want it, just send mail.
53  *
54  * Status:
55  *
56  *	Untested with multiple scanners.
57  *	Untested on SMP.
58  *	Untested on a bigendian machine.
59  *
60  * History:
61  *
62  *	20000417 starting history
63  *	20000417 fixed load oops
64  *	20000417 fixed unload oops
65  *	20000419 fixed READ IMAGE detection
66  *	20000424 started conversion to use URBs
67  *	20000502 handled short transfers as errors
68  *	20000513 rename and organisation of functions (john)
69  *	20000513 added IDs for all products supported by Windows driver (john)
70  *	20000514 Rewrote mts_scsi_queuecommand to use URBs (john)
71  *	20000514 Version 0.0.8j
72  *      20000514 Fix reporting of non-existant devices to SCSI layer (john)
73  *	20000514 Added MTS_DEBUG_INT (john)
74  *	20000514 Changed "usb-microtek" to "microtek" for consistency (john)
75  *	20000514 Stupid bug fixes (john)
76  *	20000514 Version 0.0.9j
77  *	20000515 Put transfer context and URB in mts_desc (john)
78  *	20000515 Added prelim turn off debugging support (john)
79  *	20000515 Version 0.0.10j
80  *      20000515 Fixed up URB allocation (clear URB on alloc) (john)
81  *      20000515 Version 0.0.11j
82  *	20000516 Removed unnecessary spinlock in mts_transfer_context (john)
83  *	20000516 Removed unnecessary up on instance lock in mts_remove_nolock (john)
84  *	20000516 Implemented (badly) scsi_abort (john)
85  *	20000516 Version 0.0.12j
86  *      20000517 Hopefully removed mts_remove_nolock quasideadlock (john)
87  *      20000517 Added mts_debug_dump to print ll USB info (john)
88  *	20000518 Tweaks and documentation updates (john)
89  *	20000518 Version 0.0.13j
90  *	20000518 Cleaned up abort handling (john)
91  *	20000523 Removed scsi_command and various scsi_..._resets (john)
92  *	20000523 Added unlink URB on scsi_abort, now OHCI supports it (john)
93  *	20000523 Fixed last tiresome compile warning (john)
94  *	20000523 Version 0.0.14j (though version 0.1 has come out?)
95  *	20000602 Added primitive reset
96  *	20000602 Version 0.2.0
97  *	20000603 various cosmetic changes
98  *	20000603 Version 0.2.1
99  *	20000620 minor cosmetic changes
100  *	20000620 Version 0.2.2
101  *	20000822 Hopefully fixed deadlock in mts_remove_nolock()
102  *	20000822 Fixed minor race in mts_transfer_cleanup()
103  *	20000822 Fixed deadlock on submission error in queuecommand
104  *	20000822 Version 0.2.3
105  *	20000913 Reduced module size if debugging is off
106  *	20000913 Version 0.2.4
107  *      20010210 New abort logic
108  *      20010210 Version 0.3.0
109  *	20010217 Merged scatter/gather
110  *	20010218 Version 0.4.0
111  *	20010218 Cosmetic fixes
112  *	20010218 Version 0.4.1
113  *      20010306 Abort while using scatter/gather
114  *      20010306 Version 0.4.2
115  *      20010311 Remove all timeouts and tidy up generally (john)
116  *	20010320 check return value of scsi_register()
117  *	20010320 Version 0.4.3
118  *	20010408 Identify version on module load.
119  *	20011003 Fix multiple requests
120  */
121 
122 #include <linux/module.h>
123 #include <linux/kernel.h>
124 #include <linux/signal.h>
125 #include <linux/errno.h>
126 #include <linux/random.h>
127 #include <linux/poll.h>
128 #include <linux/init.h>
129 #include <linux/slab.h>
130 #include <linux/spinlock.h>
131 #include <linux/usb.h>
132 #include <linux/proc_fs.h>
133 
134 #include <asm/atomic.h>
135 #include <linux/blkdev.h>
136 #include "../../scsi/scsi.h"
137 #include <scsi/scsi_host.h>
138 
139 #include "microtek.h"
140 
141 /*
142  * Version Information
143  */
144 #define DRIVER_VERSION "v0.4.3"
145 #define DRIVER_AUTHOR "John Fremlin <vii@penguinpowered.com>, Oliver Neukum <Oliver.Neukum@lrz.uni-muenchen.de>"
146 #define DRIVER_DESC "Microtek Scanmaker X6 USB scanner driver"
147 
148 /* Should we do debugging? */
149 
150 //#define MTS_DO_DEBUG
151 
152 /* USB layer driver interface */
153 
154 static int mts_usb_probe(struct usb_interface *intf,
155 			 const struct usb_device_id *id);
156 static void mts_usb_disconnect(struct usb_interface *intf);
157 
158 static struct usb_device_id mts_usb_ids [];
159 
160 static struct usb_driver mts_usb_driver = {
161 	.name =		"microtekX6",
162 	.probe =	mts_usb_probe,
163 	.disconnect =	mts_usb_disconnect,
164 	.id_table =	mts_usb_ids,
165 };
166 
167 
168 /* Internal driver stuff */
169 
170 #define MTS_VERSION	"0.4.3"
171 #define MTS_NAME	"microtek usb (rev " MTS_VERSION "): "
172 
173 #define MTS_WARNING(x...) \
174 	printk( KERN_WARNING MTS_NAME x )
175 #define MTS_ERROR(x...) \
176 	printk( KERN_ERR MTS_NAME x )
177 #define MTS_INT_ERROR(x...) \
178 	MTS_ERROR(x)
179 #define MTS_MESSAGE(x...) \
180 	printk( KERN_INFO MTS_NAME x )
181 
182 #if defined MTS_DO_DEBUG
183 
184 #define MTS_DEBUG(x...) \
185 	printk( KERN_DEBUG MTS_NAME x )
186 
187 #define MTS_DEBUG_GOT_HERE() \
188 	MTS_DEBUG("got to %s:%d (%s)\n", __FILE__, (int)__LINE__, __func__ )
189 #define MTS_DEBUG_INT() \
190 	do { MTS_DEBUG_GOT_HERE(); \
191 	     MTS_DEBUG("transfer = 0x%x context = 0x%x\n",(int)transfer,(int)context ); \
192 	     MTS_DEBUG("status = 0x%x data-length = 0x%x sent = 0x%x\n",transfer->status,(int)context->data_length, (int)transfer->actual_length ); \
193              mts_debug_dump(context->instance);\
194 	   } while(0)
195 #else
196 
197 #define MTS_NUL_STATEMENT do { } while(0)
198 
199 #define MTS_DEBUG(x...)	MTS_NUL_STATEMENT
200 #define MTS_DEBUG_GOT_HERE() MTS_NUL_STATEMENT
201 #define MTS_DEBUG_INT() MTS_NUL_STATEMENT
202 
203 #endif
204 
205 
206 
207 #define MTS_INT_INIT()\
208 	struct mts_transfer_context* context = (struct mts_transfer_context*)transfer->context; \
209 	MTS_DEBUG_INT();\
210 
211 #ifdef MTS_DO_DEBUG
212 
213 static inline void mts_debug_dump(struct mts_desc* desc) {
214 	MTS_DEBUG("desc at 0x%x: toggle = %02x%02x\n",
215 		  (int)desc,
216 		  (int)desc->usb_dev->toggle[1],(int)desc->usb_dev->toggle[0]
217 		);
218 	MTS_DEBUG("ep_out=%x ep_response=%x ep_image=%x\n",
219 		  usb_sndbulkpipe(desc->usb_dev,desc->ep_out),
220 		  usb_rcvbulkpipe(desc->usb_dev,desc->ep_response),
221 		  usb_rcvbulkpipe(desc->usb_dev,desc->ep_image)
222 		);
223 }
224 
225 
226 static inline void mts_show_command(struct scsi_cmnd *srb)
227 {
228 	char *what = NULL;
229 
230 	switch (srb->cmnd[0]) {
231 	case TEST_UNIT_READY: what = "TEST_UNIT_READY"; break;
232 	case REZERO_UNIT: what = "REZERO_UNIT"; break;
233 	case REQUEST_SENSE: what = "REQUEST_SENSE"; break;
234 	case FORMAT_UNIT: what = "FORMAT_UNIT"; break;
235 	case READ_BLOCK_LIMITS: what = "READ_BLOCK_LIMITS"; break;
236 	case REASSIGN_BLOCKS: what = "REASSIGN_BLOCKS"; break;
237 	case READ_6: what = "READ_6"; break;
238 	case WRITE_6: what = "WRITE_6"; break;
239 	case SEEK_6: what = "SEEK_6"; break;
240 	case READ_REVERSE: what = "READ_REVERSE"; break;
241 	case WRITE_FILEMARKS: what = "WRITE_FILEMARKS"; break;
242 	case SPACE: what = "SPACE"; break;
243 	case INQUIRY: what = "INQUIRY"; break;
244 	case RECOVER_BUFFERED_DATA: what = "RECOVER_BUFFERED_DATA"; break;
245 	case MODE_SELECT: what = "MODE_SELECT"; break;
246 	case RESERVE: what = "RESERVE"; break;
247 	case RELEASE: what = "RELEASE"; break;
248 	case COPY: what = "COPY"; break;
249 	case ERASE: what = "ERASE"; break;
250 	case MODE_SENSE: what = "MODE_SENSE"; break;
251 	case START_STOP: what = "START_STOP"; break;
252 	case RECEIVE_DIAGNOSTIC: what = "RECEIVE_DIAGNOSTIC"; break;
253 	case SEND_DIAGNOSTIC: what = "SEND_DIAGNOSTIC"; break;
254 	case ALLOW_MEDIUM_REMOVAL: what = "ALLOW_MEDIUM_REMOVAL"; break;
255 	case SET_WINDOW: what = "SET_WINDOW"; break;
256 	case READ_CAPACITY: what = "READ_CAPACITY"; break;
257 	case READ_10: what = "READ_10"; break;
258 	case WRITE_10: what = "WRITE_10"; break;
259 	case SEEK_10: what = "SEEK_10"; break;
260 	case WRITE_VERIFY: what = "WRITE_VERIFY"; break;
261 	case VERIFY: what = "VERIFY"; break;
262 	case SEARCH_HIGH: what = "SEARCH_HIGH"; break;
263 	case SEARCH_EQUAL: what = "SEARCH_EQUAL"; break;
264 	case SEARCH_LOW: what = "SEARCH_LOW"; break;
265 	case SET_LIMITS: what = "SET_LIMITS"; break;
266 	case READ_POSITION: what = "READ_POSITION"; break;
267 	case SYNCHRONIZE_CACHE: what = "SYNCHRONIZE_CACHE"; break;
268 	case LOCK_UNLOCK_CACHE: what = "LOCK_UNLOCK_CACHE"; break;
269 	case READ_DEFECT_DATA: what = "READ_DEFECT_DATA"; break;
270 	case MEDIUM_SCAN: what = "MEDIUM_SCAN"; break;
271 	case COMPARE: what = "COMPARE"; break;
272 	case COPY_VERIFY: what = "COPY_VERIFY"; break;
273 	case WRITE_BUFFER: what = "WRITE_BUFFER"; break;
274 	case READ_BUFFER: what = "READ_BUFFER"; break;
275 	case UPDATE_BLOCK: what = "UPDATE_BLOCK"; break;
276 	case READ_LONG: what = "READ_LONG"; break;
277 	case WRITE_LONG: what = "WRITE_LONG"; break;
278 	case CHANGE_DEFINITION: what = "CHANGE_DEFINITION"; break;
279 	case WRITE_SAME: what = "WRITE_SAME"; break;
280 	case READ_TOC: what = "READ_TOC"; break;
281 	case LOG_SELECT: what = "LOG_SELECT"; break;
282 	case LOG_SENSE: what = "LOG_SENSE"; break;
283 	case MODE_SELECT_10: what = "MODE_SELECT_10"; break;
284 	case MODE_SENSE_10: what = "MODE_SENSE_10"; break;
285 	case MOVE_MEDIUM: what = "MOVE_MEDIUM"; break;
286 	case READ_12: what = "READ_12"; break;
287 	case WRITE_12: what = "WRITE_12"; break;
288 	case WRITE_VERIFY_12: what = "WRITE_VERIFY_12"; break;
289 	case SEARCH_HIGH_12: what = "SEARCH_HIGH_12"; break;
290 	case SEARCH_EQUAL_12: what = "SEARCH_EQUAL_12"; break;
291 	case SEARCH_LOW_12: what = "SEARCH_LOW_12"; break;
292 	case READ_ELEMENT_STATUS: what = "READ_ELEMENT_STATUS"; break;
293 	case SEND_VOLUME_TAG: what = "SEND_VOLUME_TAG"; break;
294 	case WRITE_LONG_2: what = "WRITE_LONG_2"; break;
295 	default:
296 		MTS_DEBUG("can't decode command\n");
297 		goto out;
298 		break;
299 	}
300 	MTS_DEBUG( "Command %s (%d bytes)\n", what, srb->cmd_len);
301 
302  out:
303 	MTS_DEBUG( "  %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
304 	       srb->cmnd[0], srb->cmnd[1], srb->cmnd[2], srb->cmnd[3], srb->cmnd[4], srb->cmnd[5],
305 	       srb->cmnd[6], srb->cmnd[7], srb->cmnd[8], srb->cmnd[9]);
306 }
307 
308 #else
309 
310 static inline void mts_show_command(struct scsi_cmnd * dummy)
311 {
312 }
313 
314 static inline void mts_debug_dump(struct mts_desc* dummy)
315 {
316 }
317 
318 #endif
319 
320 static inline void mts_urb_abort(struct mts_desc* desc) {
321 	MTS_DEBUG_GOT_HERE();
322 	mts_debug_dump(desc);
323 
324 	usb_kill_urb( desc->urb );
325 }
326 
327 static int mts_slave_alloc (struct scsi_device *s)
328 {
329 	s->inquiry_len = 0x24;
330 	return 0;
331 }
332 
333 static int mts_slave_configure (struct scsi_device *s)
334 {
335 	blk_queue_dma_alignment(s->request_queue, (512 - 1));
336 	return 0;
337 }
338 
339 static int mts_scsi_abort(struct scsi_cmnd *srb)
340 {
341 	struct mts_desc* desc = (struct mts_desc*)(srb->device->host->hostdata[0]);
342 
343 	MTS_DEBUG_GOT_HERE();
344 
345 	mts_urb_abort(desc);
346 
347 	return FAILED;
348 }
349 
350 static int mts_scsi_host_reset(struct scsi_cmnd *srb)
351 {
352 	struct mts_desc* desc = (struct mts_desc*)(srb->device->host->hostdata[0]);
353 	int result;
354 
355 	MTS_DEBUG_GOT_HERE();
356 	mts_debug_dump(desc);
357 
358 	result = usb_lock_device_for_reset(desc->usb_dev, desc->usb_intf);
359 	if (result == 0) {
360 		result = usb_reset_device(desc->usb_dev);
361 		usb_unlock_device(desc->usb_dev);
362 	}
363 	return result ? FAILED : SUCCESS;
364 }
365 
366 static int
367 mts_scsi_queuecommand(struct scsi_cmnd *srb, mts_scsi_cmnd_callback callback);
368 
369 static void mts_transfer_cleanup( struct urb *transfer );
370 static void mts_do_sg(struct urb * transfer);
371 
372 static inline
373 void mts_int_submit_urb (struct urb* transfer,
374 			int pipe,
375 			void* data,
376 			unsigned length,
377 			usb_complete_t callback )
378 /* Interrupt context! */
379 
380 /* Holding transfer->context->lock! */
381 {
382 	int res;
383 
384 	MTS_INT_INIT();
385 
386 	usb_fill_bulk_urb(transfer,
387 		      context->instance->usb_dev,
388 		      pipe,
389 		      data,
390 		      length,
391 		      callback,
392 		      context
393 		);
394 
395 	res = usb_submit_urb( transfer, GFP_ATOMIC );
396 	if ( unlikely(res) ) {
397 		MTS_INT_ERROR( "could not submit URB! Error was %d\n",(int)res );
398 		context->srb->result = DID_ERROR << 16;
399 		mts_transfer_cleanup(transfer);
400 	}
401 	return;
402 }
403 
404 
405 static void mts_transfer_cleanup( struct urb *transfer )
406 /* Interrupt context! */
407 {
408 	MTS_INT_INIT();
409 
410 	if ( likely(context->final_callback != NULL) )
411 		context->final_callback(context->srb);
412 
413 }
414 
415 static void mts_transfer_done( struct urb *transfer )
416 {
417 	MTS_INT_INIT();
418 
419 	context->srb->result &= MTS_SCSI_ERR_MASK;
420 	context->srb->result |= (unsigned)(*context->scsi_status)<<1;
421 
422 	mts_transfer_cleanup(transfer);
423 
424 	return;
425 }
426 
427 
428 static void mts_get_status( struct urb *transfer )
429 /* Interrupt context! */
430 {
431 	MTS_INT_INIT();
432 
433 	mts_int_submit_urb(transfer,
434 			   usb_rcvbulkpipe(context->instance->usb_dev,
435 					   context->instance->ep_response),
436 			   context->scsi_status,
437 			   1,
438 			   mts_transfer_done );
439 }
440 
441 static void mts_data_done( struct urb* transfer )
442 /* Interrupt context! */
443 {
444 	int status = transfer->status;
445 	MTS_INT_INIT();
446 
447 	if ( context->data_length != transfer->actual_length ) {
448 		scsi_set_resid(context->srb, context->data_length -
449 			       transfer->actual_length);
450 	} else if ( unlikely(status) ) {
451 		context->srb->result = (status == -ENOENT ? DID_ABORT : DID_ERROR)<<16;
452 	}
453 
454 	mts_get_status(transfer);
455 
456 	return;
457 }
458 
459 
460 static void mts_command_done( struct urb *transfer )
461 /* Interrupt context! */
462 {
463 	int status = transfer->status;
464 	MTS_INT_INIT();
465 
466 	if ( unlikely(status) ) {
467 	        if (status == -ENOENT) {
468 		        /* We are being killed */
469 			MTS_DEBUG_GOT_HERE();
470 			context->srb->result = DID_ABORT<<16;
471                 } else {
472 		        /* A genuine error has occurred */
473 			MTS_DEBUG_GOT_HERE();
474 
475 		        context->srb->result = DID_ERROR<<16;
476                 }
477 		mts_transfer_cleanup(transfer);
478 
479 		return;
480 	}
481 
482 	if (context->srb->cmnd[0] == REQUEST_SENSE) {
483 		mts_int_submit_urb(transfer,
484 				   context->data_pipe,
485 				   context->srb->sense_buffer,
486 				   context->data_length,
487 				   mts_data_done);
488 	} else { if ( context->data ) {
489 			mts_int_submit_urb(transfer,
490 					   context->data_pipe,
491 					   context->data,
492 					   context->data_length,
493 					   scsi_sg_count(context->srb) > 1 ?
494 					           mts_do_sg : mts_data_done);
495 		} else {
496 			mts_get_status(transfer);
497 		}
498 	}
499 
500 	return;
501 }
502 
503 static void mts_do_sg (struct urb* transfer)
504 {
505 	struct scatterlist * sg;
506 	int status = transfer->status;
507 	MTS_INT_INIT();
508 
509 	MTS_DEBUG("Processing fragment %d of %d\n", context->fragment,
510 	                                          scsi_sg_count(context->srb));
511 
512 	if (unlikely(status)) {
513                 context->srb->result = (status == -ENOENT ? DID_ABORT : DID_ERROR)<<16;
514 		mts_transfer_cleanup(transfer);
515         }
516 
517 	sg = scsi_sglist(context->srb);
518 	context->fragment++;
519 	mts_int_submit_urb(transfer,
520 			   context->data_pipe,
521 			   sg_virt(&sg[context->fragment]),
522 			   sg[context->fragment].length,
523 			   context->fragment + 1 == scsi_sg_count(context->srb) ?
524 			   mts_data_done : mts_do_sg);
525 	return;
526 }
527 
528 static const u8 mts_read_image_sig[] = { 0x28, 00, 00, 00 };
529 static const u8 mts_read_image_sig_len = 4;
530 static const unsigned char mts_direction[256/8] = {
531 	0x28, 0x81, 0x14, 0x14, 0x20, 0x01, 0x90, 0x77,
532 	0x0C, 0x20, 0x00, 0x04, 0x00, 0x00, 0x00, 0x00,
533 	0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x01,
534 	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
535 };
536 
537 
538 #define MTS_DIRECTION_IS_IN(x) ((mts_direction[x>>3] >> (x & 7)) & 1)
539 
540 static void
541 mts_build_transfer_context(struct scsi_cmnd *srb, struct mts_desc* desc)
542 {
543 	int pipe;
544 	struct scatterlist * sg;
545 
546 	MTS_DEBUG_GOT_HERE();
547 
548 	desc->context.instance = desc;
549 	desc->context.srb = srb;
550 	desc->context.fragment = 0;
551 
552 	if (!scsi_bufflen(srb)) {
553 		desc->context.data = NULL;
554 		desc->context.data_length = 0;
555 		return;
556 	} else {
557 		sg = scsi_sglist(srb);
558 		desc->context.data = sg_virt(&sg[0]);
559 		desc->context.data_length = sg[0].length;
560 	}
561 
562 
563 	/* can't rely on srb->sc_data_direction */
564 
565 	/* Brutally ripped from usb-storage */
566 
567 	if ( !memcmp( srb->cmnd, mts_read_image_sig, mts_read_image_sig_len )
568 ) { 		pipe = usb_rcvbulkpipe(desc->usb_dev,desc->ep_image);
569 		MTS_DEBUG( "transfering from desc->ep_image == %d\n",
570 			   (int)desc->ep_image );
571 	} else if ( MTS_DIRECTION_IS_IN(srb->cmnd[0]) ) {
572 			pipe = usb_rcvbulkpipe(desc->usb_dev,desc->ep_response);
573 			MTS_DEBUG( "transfering from desc->ep_response == %d\n",
574 				   (int)desc->ep_response);
575 	} else {
576 		MTS_DEBUG("transfering to desc->ep_out == %d\n",
577 			  (int)desc->ep_out);
578 		pipe = usb_sndbulkpipe(desc->usb_dev,desc->ep_out);
579 	}
580 	desc->context.data_pipe = pipe;
581 }
582 
583 
584 static int
585 mts_scsi_queuecommand(struct scsi_cmnd *srb, mts_scsi_cmnd_callback callback)
586 {
587 	struct mts_desc* desc = (struct mts_desc*)(srb->device->host->hostdata[0]);
588 	int err = 0;
589 	int res;
590 
591 	MTS_DEBUG_GOT_HERE();
592 	mts_show_command(srb);
593 	mts_debug_dump(desc);
594 
595 	if ( srb->device->lun || srb->device->id || srb->device->channel ) {
596 
597 		MTS_DEBUG("Command to LUN=%d ID=%d CHANNEL=%d from SCSI layer\n",(int)srb->device->lun,(int)srb->device->id, (int)srb->device->channel );
598 
599 		MTS_DEBUG("this device doesn't exist\n");
600 
601 		srb->result = DID_BAD_TARGET << 16;
602 
603 		if(likely(callback != NULL))
604 			callback(srb);
605 
606 		goto out;
607 	}
608 
609 
610 	usb_fill_bulk_urb(desc->urb,
611 		      desc->usb_dev,
612 		      usb_sndbulkpipe(desc->usb_dev,desc->ep_out),
613 		      srb->cmnd,
614 		      srb->cmd_len,
615 		      mts_command_done,
616 		      &desc->context
617 		      );
618 
619 
620 	mts_build_transfer_context( srb, desc );
621 	desc->context.final_callback = callback;
622 
623 	/* here we need ATOMIC as we are called with the iolock */
624 	res=usb_submit_urb(desc->urb, GFP_ATOMIC);
625 
626 	if(unlikely(res)){
627 		MTS_ERROR("error %d submitting URB\n",(int)res);
628 		srb->result = DID_ERROR << 16;
629 
630 		if(likely(callback != NULL))
631 			callback(srb);
632 
633 	}
634 out:
635 	return err;
636 }
637 
638 static struct scsi_host_template mts_scsi_host_template = {
639 	.module			= THIS_MODULE,
640 	.name			= "microtekX6",
641 	.proc_name		= "microtekX6",
642 	.queuecommand		= mts_scsi_queuecommand,
643 	.eh_abort_handler	= mts_scsi_abort,
644 	.eh_host_reset_handler	= mts_scsi_host_reset,
645 	.sg_tablesize =		SG_ALL,
646 	.can_queue =		1,
647 	.this_id =		-1,
648 	.cmd_per_lun =		1,
649 	.use_clustering =	1,
650 	.emulated =		1,
651 	.slave_alloc =		mts_slave_alloc,
652 	.slave_configure =	mts_slave_configure,
653 	.max_sectors=		256, /* 128 K */
654 };
655 
656 /* The entries of microtek_table must correspond, line-by-line to
657    the entries of mts_supported_products[]. */
658 
659 static struct usb_device_id mts_usb_ids [] =
660 {
661 	{ USB_DEVICE(0x4ce, 0x0300) },
662 	{ USB_DEVICE(0x5da, 0x0094) },
663 	{ USB_DEVICE(0x5da, 0x0099) },
664 	{ USB_DEVICE(0x5da, 0x009a) },
665 	{ USB_DEVICE(0x5da, 0x00a0) },
666 	{ USB_DEVICE(0x5da, 0x00a3) },
667 	{ USB_DEVICE(0x5da, 0x80a3) },
668 	{ USB_DEVICE(0x5da, 0x80ac) },
669 	{ USB_DEVICE(0x5da, 0x00b6) },
670 	{ }						/* Terminating entry */
671 };
672 
673 MODULE_DEVICE_TABLE (usb, mts_usb_ids);
674 
675 
676 static int mts_usb_probe(struct usb_interface *intf,
677 			 const struct usb_device_id *id)
678 {
679 	int i;
680 	int ep_out = -1;
681 	int ep_in_set[3]; /* this will break if we have more than three endpoints
682 			   which is why we check */
683 	int *ep_in_current = ep_in_set;
684 	int err_retval = -ENOMEM;
685 
686 	struct mts_desc * new_desc;
687 	struct usb_device *dev = interface_to_usbdev (intf);
688 
689 	/* the current altsetting on the interface we're probing */
690 	struct usb_host_interface *altsetting;
691 
692 	MTS_DEBUG_GOT_HERE();
693 	MTS_DEBUG( "usb-device descriptor at %x\n", (int)dev );
694 
695 	MTS_DEBUG( "product id = 0x%x, vendor id = 0x%x\n",
696 		   le16_to_cpu(dev->descriptor.idProduct),
697 		   le16_to_cpu(dev->descriptor.idVendor) );
698 
699 	MTS_DEBUG_GOT_HERE();
700 
701 	/* the current altsetting on the interface we're probing */
702 	altsetting = intf->cur_altsetting;
703 
704 
705 	/* Check if the config is sane */
706 
707 	if ( altsetting->desc.bNumEndpoints != MTS_EP_TOTAL ) {
708 		MTS_WARNING( "expecting %d got %d endpoints! Bailing out.\n",
709 			     (int)MTS_EP_TOTAL, (int)altsetting->desc.bNumEndpoints );
710 		return -ENODEV;
711 	}
712 
713 	for( i = 0; i < altsetting->desc.bNumEndpoints; i++ ) {
714 		if ((altsetting->endpoint[i].desc.bmAttributes &
715 		     USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_BULK) {
716 
717 			MTS_WARNING( "can only deal with bulk endpoints; endpoint %d is not bulk.\n",
718 			     (int)altsetting->endpoint[i].desc.bEndpointAddress );
719 		} else {
720 			if (altsetting->endpoint[i].desc.bEndpointAddress &
721 			    USB_DIR_IN)
722 				*ep_in_current++
723 					= altsetting->endpoint[i].desc.bEndpointAddress &
724 					USB_ENDPOINT_NUMBER_MASK;
725 			else {
726 				if ( ep_out != -1 ) {
727 					MTS_WARNING( "can only deal with one output endpoints. Bailing out." );
728 					return -ENODEV;
729 				}
730 
731 				ep_out = altsetting->endpoint[i].desc.bEndpointAddress &
732 					USB_ENDPOINT_NUMBER_MASK;
733 			}
734 		}
735 
736 	}
737 
738 
739 	if ( ep_out == -1 ) {
740 		MTS_WARNING( "couldn't find an output bulk endpoint. Bailing out.\n" );
741 		return -ENODEV;
742 	}
743 
744 
745 	new_desc = kzalloc(sizeof(struct mts_desc), GFP_KERNEL);
746 	if (!new_desc)
747 		goto out;
748 
749 	new_desc->urb = usb_alloc_urb(0, GFP_KERNEL);
750 	if (!new_desc->urb)
751 		goto out_kfree;
752 
753 	new_desc->context.scsi_status = kmalloc(1, GFP_KERNEL);
754 	if (!new_desc->context.scsi_status)
755 		goto out_free_urb;
756 
757 	new_desc->usb_dev = dev;
758 	new_desc->usb_intf = intf;
759 
760 	/* endpoints */
761 	new_desc->ep_out = ep_out;
762 	new_desc->ep_response = ep_in_set[0];
763 	new_desc->ep_image = ep_in_set[1];
764 
765 	if ( new_desc->ep_out != MTS_EP_OUT )
766 		MTS_WARNING( "will this work? Command EP is not usually %d\n",
767 			     (int)new_desc->ep_out );
768 
769 	if ( new_desc->ep_response != MTS_EP_RESPONSE )
770 		MTS_WARNING( "will this work? Response EP is not usually %d\n",
771 			     (int)new_desc->ep_response );
772 
773 	if ( new_desc->ep_image != MTS_EP_IMAGE )
774 		MTS_WARNING( "will this work? Image data EP is not usually %d\n",
775 			     (int)new_desc->ep_image );
776 
777 	new_desc->host = scsi_host_alloc(&mts_scsi_host_template,
778 			sizeof(new_desc));
779 	if (!new_desc->host)
780 		goto out_kfree2;
781 
782 	new_desc->host->hostdata[0] = (unsigned long)new_desc;
783 	if (scsi_add_host(new_desc->host, &dev->dev)) {
784 		err_retval = -EIO;
785 		goto out_host_put;
786 	}
787 	scsi_scan_host(new_desc->host);
788 
789 	usb_set_intfdata(intf, new_desc);
790 	return 0;
791 
792  out_host_put:
793 	scsi_host_put(new_desc->host);
794  out_kfree2:
795 	kfree(new_desc->context.scsi_status);
796  out_free_urb:
797 	usb_free_urb(new_desc->urb);
798  out_kfree:
799 	kfree(new_desc);
800  out:
801 	return err_retval;
802 }
803 
804 static void mts_usb_disconnect (struct usb_interface *intf)
805 {
806 	struct mts_desc *desc = usb_get_intfdata(intf);
807 
808 	usb_set_intfdata(intf, NULL);
809 
810 	usb_kill_urb(desc->urb);
811 	scsi_remove_host(desc->host);
812 
813 	scsi_host_put(desc->host);
814 	usb_free_urb(desc->urb);
815 	kfree(desc->context.scsi_status);
816 	kfree(desc);
817 }
818 
819 
820 static int __init microtek_drv_init(void)
821 {
822 	return usb_register(&mts_usb_driver);
823 }
824 
825 static void __exit microtek_drv_exit(void)
826 {
827 	usb_deregister(&mts_usb_driver);
828 }
829 
830 module_init(microtek_drv_init);
831 module_exit(microtek_drv_exit);
832 
833 MODULE_AUTHOR( DRIVER_AUTHOR );
834 MODULE_DESCRIPTION( DRIVER_DESC );
835 MODULE_LICENSE("GPL");
836