xref: /openbmc/linux/drivers/usb/image/mdc800.c (revision 87c2ce3b)
1 /*
2  * copyright (C) 1999/2000 by Henning Zabel <henning@uni-paderborn.de>
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License as published by the
6  * Free Software Foundation; either version 2 of the License, or (at your
7  * option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software Foundation,
16  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17  */
18 
19 
20 /*
21  *	USB-Kernel Driver for the Mustek MDC800 Digital Camera
22  *	(c) 1999/2000 Henning Zabel <henning@uni-paderborn.de>
23  *
24  *
25  * The driver brings the USB functions of the MDC800 to Linux.
26  * To use the Camera you must support the USB Protocol of the camera
27  * to the Kernel Node.
28  * The Driver uses a misc device Node. Create it with :
29  * mknod /dev/mustek c 180 32
30  *
31  * The driver supports only one camera.
32  *
33  * Fix: mdc800 used sleep_on and slept with io_lock held.
34  * Converted sleep_on to waitqueues with schedule_timeout and made io_lock
35  * a semaphore from a spinlock.
36  * by Oliver Neukum <oliver@neukum.name>
37  * (02/12/2001)
38  *
39  * Identify version on module load.
40  * (08/04/2001) gb
41  *
42  * version 0.7.5
43  * Fixed potential SMP races with Spinlocks.
44  * Thanks to Oliver Neukum <oliver@neukum.name> who
45  * noticed the race conditions.
46  * (30/10/2000)
47  *
48  * Fixed: Setting urb->dev before submitting urb.
49  * by Greg KH <greg@kroah.com>
50  * (13/10/2000)
51  *
52  * version 0.7.3
53  * bugfix : The mdc800->state field gets set to READY after the
54  * the diconnect function sets it to NOT_CONNECTED. This makes the
55  * driver running like the camera is connected and causes some
56  * hang ups.
57  *
58  * version 0.7.1
59  * MOD_INC and MOD_DEC are changed in usb_probe to prevent load/unload
60  * problems when compiled as Module.
61  * (04/04/2000)
62  *
63  * The mdc800 driver gets assigned the USB Minor 32-47. The Registration
64  * was updated to use these values.
65  * (26/03/2000)
66  *
67  * The Init und Exit Module Function are updated.
68  * (01/03/2000)
69  *
70  * version 0.7.0
71  * Rewrite of the driver : The driver now uses URB's. The old stuff
72  * has been removed.
73  *
74  * version 0.6.0
75  * Rewrite of this driver: The Emulation of the rs232 protocoll
76  * has been removed from the driver. A special executeCommand function
77  * for this driver is included to gphoto.
78  * The driver supports two kind of communication to bulk endpoints.
79  * Either with the dev->bus->ops->bulk... or with callback function.
80  * (09/11/1999)
81  *
82  * version 0.5.0:
83  * first Version that gets a version number. Most of the needed
84  * functions work.
85  * (20/10/1999)
86  */
87 
88 #include <linux/sched.h>
89 #include <linux/signal.h>
90 #include <linux/spinlock.h>
91 #include <linux/errno.h>
92 #include <linux/random.h>
93 #include <linux/poll.h>
94 #include <linux/init.h>
95 #include <linux/slab.h>
96 #include <linux/module.h>
97 #include <linux/smp_lock.h>
98 #include <linux/wait.h>
99 
100 #include <linux/usb.h>
101 #include <linux/fs.h>
102 
103 /*
104  * Version Information
105  */
106 #define DRIVER_VERSION "v0.7.5 (30/10/2000)"
107 #define DRIVER_AUTHOR "Henning Zabel <henning@uni-paderborn.de>"
108 #define DRIVER_DESC "USB Driver for Mustek MDC800 Digital Camera"
109 
110 /* Vendor and Product Information */
111 #define MDC800_VENDOR_ID 	0x055f
112 #define MDC800_PRODUCT_ID	0xa800
113 
114 /* Timeouts (msec) */
115 #define TO_DOWNLOAD_GET_READY		1500
116 #define TO_DOWNLOAD_GET_BUSY		1500
117 #define TO_WRITE_GET_READY		1000
118 #define TO_DEFAULT_COMMAND		5000
119 #define TO_READ_FROM_IRQ 		TO_DEFAULT_COMMAND
120 #define TO_GET_READY			TO_DEFAULT_COMMAND
121 
122 /* Minor Number of the device (create with mknod /dev/mustek c 180 32) */
123 #define MDC800_DEVICE_MINOR_BASE 32
124 
125 
126 /**************************************************************************
127 	Data and structs
128 ***************************************************************************/
129 
130 
131 typedef enum {
132 	NOT_CONNECTED, READY, WORKING, DOWNLOAD
133 } mdc800_state;
134 
135 
136 /* Data for the driver */
137 struct mdc800_data
138 {
139 	struct usb_device *	dev;			// Device Data
140 	mdc800_state 		state;
141 
142 	unsigned int		endpoint [4];
143 
144 	struct urb *		irq_urb;
145 	wait_queue_head_t	irq_wait;
146 	int			irq_woken;
147 	char*			irq_urb_buffer;
148 
149 	int			camera_busy;          // is camera busy ?
150 	int 			camera_request_ready; // Status to synchronize with irq
151 	char 			camera_response [8];  // last Bytes send after busy
152 
153 	struct urb *   		write_urb;
154 	char*			write_urb_buffer;
155 	wait_queue_head_t	write_wait;
156 	int			written;
157 
158 
159 	struct urb *   		download_urb;
160 	char*			download_urb_buffer;
161 	wait_queue_head_t	download_wait;
162 	int			downloaded;
163 	int			download_left;		// Bytes left to download ?
164 
165 
166 	/* Device Data */
167 	char			out [64];	// Answer Buffer
168 	int 			out_ptr;	// Index to the first not readen byte
169 	int			out_count;	// Bytes in the buffer
170 
171 	int			open;		// Camera device open ?
172 	struct semaphore	io_lock;	// IO -lock
173 
174 	char 			in [8];		// Command Input Buffer
175 	int  			in_count;
176 
177 	int			pic_index;	// Cache for the Imagesize (-1 for nothing cached )
178 	int			pic_len;
179 	int			minor;
180 };
181 
182 
183 /* Specification of the Endpoints */
184 static struct usb_endpoint_descriptor mdc800_ed [4] =
185 {
186 	{
187 		.bLength = 		0,
188 		.bDescriptorType =	0,
189 		.bEndpointAddress =	0x01,
190 		.bmAttributes = 	0x02,
191 		.wMaxPacketSize =	__constant_cpu_to_le16(8),
192 		.bInterval = 		0,
193 		.bRefresh = 		0,
194 		.bSynchAddress = 	0,
195 	},
196 	{
197 		.bLength = 		0,
198 		.bDescriptorType = 	0,
199 		.bEndpointAddress = 	0x82,
200 		.bmAttributes = 	0x03,
201 		.wMaxPacketSize = 	__constant_cpu_to_le16(8),
202 		.bInterval = 		0,
203 		.bRefresh = 		0,
204 		.bSynchAddress = 	0,
205 	},
206 	{
207 		.bLength = 		0,
208 		.bDescriptorType = 	0,
209 		.bEndpointAddress = 	0x03,
210 		.bmAttributes = 	0x02,
211 		.wMaxPacketSize = 	__constant_cpu_to_le16(64),
212 		.bInterval = 		0,
213 		.bRefresh = 		0,
214 		.bSynchAddress = 	0,
215 	},
216 	{
217 		.bLength = 		0,
218 		.bDescriptorType = 	0,
219 		.bEndpointAddress = 	0x84,
220 		.bmAttributes = 	0x02,
221 		.wMaxPacketSize = 	__constant_cpu_to_le16(64),
222 		.bInterval = 		0,
223 		.bRefresh = 		0,
224 		.bSynchAddress = 	0,
225 	},
226 };
227 
228 /* The Variable used by the driver */
229 static struct mdc800_data* mdc800;
230 
231 
232 /***************************************************************************
233 	The USB Part of the driver
234 ****************************************************************************/
235 
236 static int mdc800_endpoint_equals (struct usb_endpoint_descriptor *a,struct usb_endpoint_descriptor *b)
237 {
238 	return (
239 		   ( a->bEndpointAddress == b->bEndpointAddress )
240 		&& ( a->bmAttributes     == b->bmAttributes     )
241 		&& ( a->wMaxPacketSize   == b->wMaxPacketSize   )
242 	);
243 }
244 
245 
246 /*
247  * Checks whether the camera responds busy
248  */
249 static int mdc800_isBusy (char* ch)
250 {
251 	int i=0;
252 	while (i<8)
253 	{
254 		if (ch [i] != (char)0x99)
255 			return 0;
256 		i++;
257 	}
258 	return 1;
259 }
260 
261 
262 /*
263  * Checks whether the Camera is ready
264  */
265 static int mdc800_isReady (char *ch)
266 {
267 	int i=0;
268 	while (i<8)
269 	{
270 		if (ch [i] != (char)0xbb)
271 			return 0;
272 		i++;
273 	}
274 	return 1;
275 }
276 
277 
278 
279 /*
280  * USB IRQ Handler for InputLine
281  */
282 static void mdc800_usb_irq (struct urb *urb, struct pt_regs *res)
283 {
284 	int data_received=0, wake_up;
285 	unsigned char* b=urb->transfer_buffer;
286 	struct mdc800_data* mdc800=urb->context;
287 
288 	if (urb->status >= 0)
289 	{
290 
291 		//dbg ("%i %i %i %i %i %i %i %i \n",b[0],b[1],b[2],b[3],b[4],b[5],b[6],b[7]);
292 
293 		if (mdc800_isBusy (b))
294 		{
295 			if (!mdc800->camera_busy)
296 			{
297 				mdc800->camera_busy=1;
298 				dbg ("gets busy");
299 			}
300 		}
301 		else
302 		{
303 			if (mdc800->camera_busy && mdc800_isReady (b))
304 			{
305 				mdc800->camera_busy=0;
306 				dbg ("gets ready");
307 			}
308 		}
309 		if (!(mdc800_isBusy (b) || mdc800_isReady (b)))
310 		{
311 			/* Store Data in camera_answer field */
312 			dbg ("%i %i %i %i %i %i %i %i ",b[0],b[1],b[2],b[3],b[4],b[5],b[6],b[7]);
313 
314 			memcpy (mdc800->camera_response,b,8);
315 			data_received=1;
316 		}
317 	}
318 	wake_up= ( mdc800->camera_request_ready > 0 )
319 		&&
320 		(
321 			((mdc800->camera_request_ready == 1) && (!mdc800->camera_busy))
322 		||
323 			((mdc800->camera_request_ready == 2) && data_received)
324 		||
325 			((mdc800->camera_request_ready == 3) && (mdc800->camera_busy))
326 		||
327 			(urb->status < 0)
328 		);
329 
330 	if (wake_up)
331 	{
332 		mdc800->camera_request_ready=0;
333 		mdc800->irq_woken=1;
334 		wake_up (&mdc800->irq_wait);
335 	}
336 }
337 
338 
339 /*
340  * Waits a while until the irq responds that camera is ready
341  *
342  *  mode : 0: Wait for camera gets ready
343  *         1: Wait for receiving data
344  *         2: Wait for camera gets busy
345  *
346  * msec: Time to wait
347  */
348 static int mdc800_usb_waitForIRQ (int mode, int msec)
349 {
350 	mdc800->camera_request_ready=1+mode;
351 
352 	wait_event_timeout(mdc800->irq_wait, mdc800->irq_woken, msec*HZ/1000);
353 	mdc800->irq_woken = 0;
354 
355 	if (mdc800->camera_request_ready>0)
356 	{
357 		mdc800->camera_request_ready=0;
358 		err ("timeout waiting for camera.");
359 		return -1;
360 	}
361 
362 	if (mdc800->state == NOT_CONNECTED)
363 	{
364 		warn ("Camera gets disconnected during waiting for irq.");
365 		mdc800->camera_request_ready=0;
366 		return -2;
367 	}
368 
369 	return 0;
370 }
371 
372 
373 /*
374  * The write_urb callback function
375  */
376 static void mdc800_usb_write_notify (struct urb *urb, struct pt_regs *res)
377 {
378 	struct mdc800_data* mdc800=urb->context;
379 
380 	if (urb->status != 0)
381 	{
382 		err ("writing command fails (status=%i)", urb->status);
383 	}
384 	else
385 	{
386 		mdc800->state=READY;
387 	}
388 	mdc800->written = 1;
389 	wake_up (&mdc800->write_wait);
390 }
391 
392 
393 /*
394  * The download_urb callback function
395  */
396 static void mdc800_usb_download_notify (struct urb *urb, struct pt_regs *res)
397 {
398 	struct mdc800_data* mdc800=urb->context;
399 
400 	if (urb->status == 0)
401 	{
402 		/* Fill output buffer with these data */
403 		memcpy (mdc800->out,  urb->transfer_buffer, 64);
404 		mdc800->out_count=64;
405 		mdc800->out_ptr=0;
406 		mdc800->download_left-=64;
407 		if (mdc800->download_left == 0)
408 		{
409 			mdc800->state=READY;
410 		}
411 	}
412 	else
413 	{
414 		err ("request bytes fails (status:%i)", urb->status);
415 	}
416 	mdc800->downloaded = 1;
417 	wake_up (&mdc800->download_wait);
418 }
419 
420 
421 /***************************************************************************
422 	Probing for the Camera
423  ***************************************************************************/
424 
425 static struct usb_driver mdc800_usb_driver;
426 static struct file_operations mdc800_device_ops;
427 static struct usb_class_driver mdc800_class = {
428 	.name =		"mdc800%d",
429 	.fops =		&mdc800_device_ops,
430 	.minor_base =	MDC800_DEVICE_MINOR_BASE,
431 };
432 
433 
434 /*
435  * Callback to search the Mustek MDC800 on the USB Bus
436  */
437 static int mdc800_usb_probe (struct usb_interface *intf,
438 			       const struct usb_device_id *id)
439 {
440 	int i,j;
441 	struct usb_host_interface *intf_desc;
442 	struct usb_device *dev = interface_to_usbdev (intf);
443 	int irq_interval=0;
444 	int retval;
445 
446 	dbg ("(mdc800_usb_probe) called.");
447 
448 
449 	if (mdc800->dev != NULL)
450 	{
451 		warn ("only one Mustek MDC800 is supported.");
452 		return -ENODEV;
453 	}
454 
455 	if (dev->descriptor.bNumConfigurations != 1)
456 	{
457 		err ("probe fails -> wrong Number of Configuration");
458 		return -ENODEV;
459 	}
460 	intf_desc = intf->cur_altsetting;
461 
462 	if (
463 			( intf_desc->desc.bInterfaceClass != 0xff )
464 		||	( intf_desc->desc.bInterfaceSubClass != 0 )
465 		|| ( intf_desc->desc.bInterfaceProtocol != 0 )
466 		|| ( intf_desc->desc.bNumEndpoints != 4)
467 	)
468 	{
469 		err ("probe fails -> wrong Interface");
470 		return -ENODEV;
471 	}
472 
473 	/* Check the Endpoints */
474 	for (i=0; i<4; i++)
475 	{
476 		mdc800->endpoint[i]=-1;
477 		for (j=0; j<4; j++)
478 		{
479 			if (mdc800_endpoint_equals (&intf_desc->endpoint [j].desc,&mdc800_ed [i]))
480 			{
481 				mdc800->endpoint[i]=intf_desc->endpoint [j].desc.bEndpointAddress ;
482 				if (i==1)
483 				{
484 					irq_interval=intf_desc->endpoint [j].desc.bInterval;
485 				}
486 
487 				continue;
488 			}
489 		}
490 		if (mdc800->endpoint[i] == -1)
491 		{
492 			err ("probe fails -> Wrong Endpoints.");
493 			return -ENODEV;
494 		}
495 	}
496 
497 
498 	info ("Found Mustek MDC800 on USB.");
499 
500 	down (&mdc800->io_lock);
501 
502 	retval = usb_register_dev(intf, &mdc800_class);
503 	if (retval) {
504 		err ("Not able to get a minor for this device.");
505 		return -ENODEV;
506 	}
507 
508 	mdc800->dev=dev;
509 	mdc800->open=0;
510 
511 	/* Setup URB Structs */
512 	usb_fill_int_urb (
513 		mdc800->irq_urb,
514 		mdc800->dev,
515 		usb_rcvintpipe (mdc800->dev,mdc800->endpoint [1]),
516 		mdc800->irq_urb_buffer,
517 		8,
518 		mdc800_usb_irq,
519 		mdc800,
520 		irq_interval
521 	);
522 
523 	usb_fill_bulk_urb (
524 		mdc800->write_urb,
525 		mdc800->dev,
526 		usb_sndbulkpipe (mdc800->dev, mdc800->endpoint[0]),
527 		mdc800->write_urb_buffer,
528 		8,
529 		mdc800_usb_write_notify,
530 		mdc800
531 	);
532 
533 	usb_fill_bulk_urb (
534 		mdc800->download_urb,
535 		mdc800->dev,
536 		usb_rcvbulkpipe (mdc800->dev, mdc800->endpoint [3]),
537 		mdc800->download_urb_buffer,
538 		64,
539 		mdc800_usb_download_notify,
540 		mdc800
541 	);
542 
543 	mdc800->state=READY;
544 
545 	up (&mdc800->io_lock);
546 
547 	usb_set_intfdata(intf, mdc800);
548 	return 0;
549 }
550 
551 
552 /*
553  * Disconnect USB device (maybe the MDC800)
554  */
555 static void mdc800_usb_disconnect (struct usb_interface *intf)
556 {
557 	struct mdc800_data* mdc800 = usb_get_intfdata(intf);
558 
559 	dbg ("(mdc800_usb_disconnect) called");
560 
561 	if (mdc800) {
562 		if (mdc800->state == NOT_CONNECTED)
563 			return;
564 
565 		usb_deregister_dev(intf, &mdc800_class);
566 
567 		mdc800->state=NOT_CONNECTED;
568 
569 		usb_kill_urb(mdc800->irq_urb);
570 		usb_kill_urb(mdc800->write_urb);
571 		usb_kill_urb(mdc800->download_urb);
572 
573 		mdc800->dev = NULL;
574 		usb_set_intfdata(intf, NULL);
575 	}
576 	info ("Mustek MDC800 disconnected from USB.");
577 }
578 
579 
580 /***************************************************************************
581 	The Misc device Part (file_operations)
582 ****************************************************************************/
583 
584 /*
585  * This Function calc the Answersize for a command.
586  */
587 static int mdc800_getAnswerSize (char command)
588 {
589 	switch ((unsigned char) command)
590 	{
591 		case 0x2a:
592 		case 0x49:
593 		case 0x51:
594 		case 0x0d:
595 		case 0x20:
596 		case 0x07:
597 		case 0x01:
598 		case 0x25:
599 		case 0x00:
600 			return 8;
601 
602 		case 0x05:
603 		case 0x3e:
604 			return mdc800->pic_len;
605 
606 		case 0x09:
607 			return 4096;
608 
609 		default:
610 			return 0;
611 	}
612 }
613 
614 
615 /*
616  * Init the device: (1) alloc mem (2) Increase MOD Count ..
617  */
618 static int mdc800_device_open (struct inode* inode, struct file *file)
619 {
620 	int retval=0;
621 	int errn=0;
622 
623 	down (&mdc800->io_lock);
624 
625 	if (mdc800->state == NOT_CONNECTED)
626 	{
627 		errn=-EBUSY;
628 		goto error_out;
629 	}
630 	if (mdc800->open)
631 	{
632 		errn=-EBUSY;
633 		goto error_out;
634 	}
635 
636 	mdc800->in_count=0;
637 	mdc800->out_count=0;
638 	mdc800->out_ptr=0;
639 	mdc800->pic_index=0;
640 	mdc800->pic_len=-1;
641 	mdc800->download_left=0;
642 
643 	mdc800->camera_busy=0;
644 	mdc800->camera_request_ready=0;
645 
646 	retval=0;
647 	mdc800->irq_urb->dev = mdc800->dev;
648 	if (usb_submit_urb (mdc800->irq_urb, GFP_KERNEL))
649 	{
650 		err ("request USB irq fails (submit_retval=%i urb_status=%i).",retval, mdc800->irq_urb->status);
651 		errn = -EIO;
652 		goto error_out;
653 	}
654 
655 	mdc800->open=1;
656 	dbg ("Mustek MDC800 device opened.");
657 
658 error_out:
659 	up (&mdc800->io_lock);
660 	return errn;
661 }
662 
663 
664 /*
665  * Close the Camera and release Memory
666  */
667 static int mdc800_device_release (struct inode* inode, struct file *file)
668 {
669 	int retval=0;
670 	dbg ("Mustek MDC800 device closed.");
671 
672 	down (&mdc800->io_lock);
673 	if (mdc800->open && (mdc800->state != NOT_CONNECTED))
674 	{
675 		usb_kill_urb(mdc800->irq_urb);
676 		usb_kill_urb(mdc800->write_urb);
677 		usb_kill_urb(mdc800->download_urb);
678 		mdc800->open=0;
679 	}
680 	else
681 	{
682 		retval=-EIO;
683 	}
684 
685 	up(&mdc800->io_lock);
686 	return retval;
687 }
688 
689 
690 /*
691  * The Device read callback Function
692  */
693 static ssize_t mdc800_device_read (struct file *file, char __user *buf, size_t len, loff_t *pos)
694 {
695 	size_t left=len, sts=len; /* single transfer size */
696 	char __user *ptr = buf;
697 
698 	down (&mdc800->io_lock);
699 	if (mdc800->state == NOT_CONNECTED)
700 	{
701 		up (&mdc800->io_lock);
702 		return -EBUSY;
703 	}
704 	if (mdc800->state == WORKING)
705 	{
706 		warn ("Illegal State \"working\" reached during read ?!");
707 		up (&mdc800->io_lock);
708 		return -EBUSY;
709 	}
710 	if (!mdc800->open)
711 	{
712 		up (&mdc800->io_lock);
713 		return -EBUSY;
714 	}
715 
716 	while (left)
717 	{
718 		if (signal_pending (current))
719 		{
720 			up (&mdc800->io_lock);
721 			return -EINTR;
722 		}
723 
724 		sts=left > (mdc800->out_count-mdc800->out_ptr)?mdc800->out_count-mdc800->out_ptr:left;
725 
726 		if (sts <= 0)
727 		{
728 			/* Too less Data in buffer */
729 			if (mdc800->state == DOWNLOAD)
730 			{
731 				mdc800->out_count=0;
732 				mdc800->out_ptr=0;
733 
734 				/* Download -> Request new bytes */
735 				mdc800->download_urb->dev = mdc800->dev;
736 				if (usb_submit_urb (mdc800->download_urb, GFP_KERNEL))
737 				{
738 					err ("Can't submit download urb (status=%i)",mdc800->download_urb->status);
739 					up (&mdc800->io_lock);
740 					return len-left;
741 				}
742 				wait_event_timeout(mdc800->download_wait, mdc800->downloaded,
743 										TO_DOWNLOAD_GET_READY*HZ/1000);
744 				mdc800->downloaded = 0;
745 				if (mdc800->download_urb->status != 0)
746 				{
747 					err ("request download-bytes fails (status=%i)",mdc800->download_urb->status);
748 					up (&mdc800->io_lock);
749 					return len-left;
750 				}
751 			}
752 			else
753 			{
754 				/* No more bytes -> that's an error*/
755 				up (&mdc800->io_lock);
756 				return -EIO;
757 			}
758 		}
759 		else
760 		{
761 			/* Copy Bytes */
762 			if (copy_to_user(ptr, &mdc800->out [mdc800->out_ptr],
763 						sts)) {
764 				up(&mdc800->io_lock);
765 				return -EFAULT;
766 			}
767 			ptr+=sts;
768 			left-=sts;
769 			mdc800->out_ptr+=sts;
770 		}
771 	}
772 
773 	up (&mdc800->io_lock);
774 	return len-left;
775 }
776 
777 
778 /*
779  * The Device write callback Function
780  * If a 8Byte Command is received, it will be send to the camera.
781  * After this the driver initiates the request for the answer or
782  * just waits until the camera becomes ready.
783  */
784 static ssize_t mdc800_device_write (struct file *file, const char __user *buf, size_t len, loff_t *pos)
785 {
786 	size_t i=0;
787 
788 	down (&mdc800->io_lock);
789 	if (mdc800->state != READY)
790 	{
791 		up (&mdc800->io_lock);
792 		return -EBUSY;
793 	}
794 	if (!mdc800->open )
795 	{
796 		up (&mdc800->io_lock);
797 		return -EBUSY;
798 	}
799 
800 	while (i<len)
801 	{
802 		unsigned char c;
803 		if (signal_pending (current))
804 		{
805 			up (&mdc800->io_lock);
806 			return -EINTR;
807 		}
808 
809 		if(get_user(c, buf+i))
810 		{
811 			up(&mdc800->io_lock);
812 			return -EFAULT;
813 		}
814 
815 		/* check for command start */
816 		if (c == 0x55)
817 		{
818 			mdc800->in_count=0;
819 			mdc800->out_count=0;
820 			mdc800->out_ptr=0;
821 			mdc800->download_left=0;
822 		}
823 
824 		/* save command byte */
825 		if (mdc800->in_count < 8)
826 		{
827 			mdc800->in[mdc800->in_count] = c;
828 			mdc800->in_count++;
829 		}
830 		else
831 		{
832 			up (&mdc800->io_lock);
833 			return -EIO;
834 		}
835 
836 		/* Command Buffer full ? -> send it to camera */
837 		if (mdc800->in_count == 8)
838 		{
839 			int answersize;
840 
841 			if (mdc800_usb_waitForIRQ (0,TO_GET_READY))
842 			{
843 				err ("Camera didn't get ready.\n");
844 				up (&mdc800->io_lock);
845 				return -EIO;
846 			}
847 
848 			answersize=mdc800_getAnswerSize (mdc800->in[1]);
849 
850 			mdc800->state=WORKING;
851 			memcpy (mdc800->write_urb->transfer_buffer, mdc800->in,8);
852 			mdc800->write_urb->dev = mdc800->dev;
853 			if (usb_submit_urb (mdc800->write_urb, GFP_KERNEL))
854 			{
855 				err ("submitting write urb fails (status=%i)", mdc800->write_urb->status);
856 				up (&mdc800->io_lock);
857 				return -EIO;
858 			}
859 			wait_event_timeout(mdc800->write_wait, mdc800->written, TO_WRITE_GET_READY*HZ/1000);
860 			mdc800->written = 0;
861 			if (mdc800->state == WORKING)
862 			{
863 				usb_kill_urb(mdc800->write_urb);
864 				up (&mdc800->io_lock);
865 				return -EIO;
866 			}
867 
868 			switch ((unsigned char) mdc800->in[1])
869 			{
870 				case 0x05: /* Download Image */
871 				case 0x3e: /* Take shot in Fine Mode (WCam Mode) */
872 					if (mdc800->pic_len < 0)
873 					{
874 						err ("call 0x07 before 0x05,0x3e");
875 						mdc800->state=READY;
876 						up (&mdc800->io_lock);
877 						return -EIO;
878 					}
879 					mdc800->pic_len=-1;
880 
881 				case 0x09: /* Download Thumbnail */
882 					mdc800->download_left=answersize+64;
883 					mdc800->state=DOWNLOAD;
884 					mdc800_usb_waitForIRQ (0,TO_DOWNLOAD_GET_BUSY);
885 					break;
886 
887 
888 				default:
889 					if (answersize)
890 					{
891 
892 						if (mdc800_usb_waitForIRQ (1,TO_READ_FROM_IRQ))
893 						{
894 							err ("requesting answer from irq fails");
895 							up (&mdc800->io_lock);
896 							return -EIO;
897 						}
898 
899 						/* Write dummy data, (this is ugly but part of the USB Protocol */
900 						/* if you use endpoint 1 as bulk and not as irq) */
901 						memcpy (mdc800->out, mdc800->camera_response,8);
902 
903 						/* This is the interpreted answer */
904 						memcpy (&mdc800->out[8], mdc800->camera_response,8);
905 
906 						mdc800->out_ptr=0;
907 						mdc800->out_count=16;
908 
909 						/* Cache the Imagesize, if command was getImageSize */
910 						if (mdc800->in [1] == (char) 0x07)
911 						{
912 							mdc800->pic_len=(int) 65536*(unsigned char) mdc800->camera_response[0]+256*(unsigned char) mdc800->camera_response[1]+(unsigned char) mdc800->camera_response[2];
913 
914 							dbg ("cached imagesize = %i",mdc800->pic_len);
915 						}
916 
917 					}
918 					else
919 					{
920 						if (mdc800_usb_waitForIRQ (0,TO_DEFAULT_COMMAND))
921 						{
922 							err ("Command Timeout.");
923 							up (&mdc800->io_lock);
924 							return -EIO;
925 						}
926 					}
927 					mdc800->state=READY;
928 					break;
929 			}
930 		}
931 		i++;
932 	}
933 	up (&mdc800->io_lock);
934 	return i;
935 }
936 
937 
938 /***************************************************************************
939 	Init and Cleanup this driver (Structs and types)
940 ****************************************************************************/
941 
942 /* File Operations of this drivers */
943 static struct file_operations mdc800_device_ops =
944 {
945 	.owner =	THIS_MODULE,
946 	.read =		mdc800_device_read,
947 	.write =	mdc800_device_write,
948 	.open =		mdc800_device_open,
949 	.release =	mdc800_device_release,
950 };
951 
952 
953 
954 static struct usb_device_id mdc800_table [] = {
955 	{ USB_DEVICE(MDC800_VENDOR_ID, MDC800_PRODUCT_ID) },
956 	{ }						/* Terminating entry */
957 };
958 
959 MODULE_DEVICE_TABLE (usb, mdc800_table);
960 /*
961  * USB Driver Struct for this device
962  */
963 static struct usb_driver mdc800_usb_driver =
964 {
965 	.name =		"mdc800",
966 	.probe =	mdc800_usb_probe,
967 	.disconnect =	mdc800_usb_disconnect,
968 	.id_table =	mdc800_table
969 };
970 
971 
972 
973 /************************************************************************
974 	Init and Cleanup this driver (Main Functions)
975 *************************************************************************/
976 
977 static int __init usb_mdc800_init (void)
978 {
979 	int retval = -ENODEV;
980 	/* Allocate Memory */
981 	mdc800=kmalloc (sizeof (struct mdc800_data), GFP_KERNEL);
982 	if (!mdc800)
983 		goto cleanup_on_fail;
984 
985 	memset(mdc800, 0, sizeof(struct mdc800_data));
986 	mdc800->dev = NULL;
987 	mdc800->open=0;
988 	mdc800->state=NOT_CONNECTED;
989 	init_MUTEX (&mdc800->io_lock);
990 
991 	init_waitqueue_head (&mdc800->irq_wait);
992 	init_waitqueue_head (&mdc800->write_wait);
993 	init_waitqueue_head (&mdc800->download_wait);
994 
995 	mdc800->irq_woken = 0;
996 	mdc800->downloaded = 0;
997 	mdc800->written = 0;
998 
999 	mdc800->irq_urb_buffer=kmalloc (8, GFP_KERNEL);
1000 	if (!mdc800->irq_urb_buffer)
1001 		goto cleanup_on_fail;
1002 	mdc800->write_urb_buffer=kmalloc (8, GFP_KERNEL);
1003 	if (!mdc800->write_urb_buffer)
1004 		goto cleanup_on_fail;
1005 	mdc800->download_urb_buffer=kmalloc (64, GFP_KERNEL);
1006 	if (!mdc800->download_urb_buffer)
1007 		goto cleanup_on_fail;
1008 
1009 	mdc800->irq_urb=usb_alloc_urb (0, GFP_KERNEL);
1010 	if (!mdc800->irq_urb)
1011 		goto cleanup_on_fail;
1012 	mdc800->download_urb=usb_alloc_urb (0, GFP_KERNEL);
1013 	if (!mdc800->download_urb)
1014 		goto cleanup_on_fail;
1015 	mdc800->write_urb=usb_alloc_urb (0, GFP_KERNEL);
1016 	if (!mdc800->write_urb)
1017 		goto cleanup_on_fail;
1018 
1019 	/* Register the driver */
1020 	retval = usb_register(&mdc800_usb_driver);
1021 	if (retval)
1022 		goto cleanup_on_fail;
1023 
1024 	info (DRIVER_VERSION ":" DRIVER_DESC);
1025 
1026 	return 0;
1027 
1028 	/* Clean driver up, when something fails */
1029 
1030 cleanup_on_fail:
1031 
1032 	if (mdc800 != NULL)
1033 	{
1034 		err ("can't alloc memory!");
1035 
1036 		kfree(mdc800->download_urb_buffer);
1037 		kfree(mdc800->write_urb_buffer);
1038 		kfree(mdc800->irq_urb_buffer);
1039 
1040 		usb_free_urb(mdc800->write_urb);
1041 		usb_free_urb(mdc800->download_urb);
1042 		usb_free_urb(mdc800->irq_urb);
1043 
1044 		kfree (mdc800);
1045 	}
1046 	mdc800 = NULL;
1047 	return retval;
1048 }
1049 
1050 
1051 static void __exit usb_mdc800_cleanup (void)
1052 {
1053 	usb_deregister (&mdc800_usb_driver);
1054 
1055 	usb_free_urb (mdc800->irq_urb);
1056 	usb_free_urb (mdc800->download_urb);
1057 	usb_free_urb (mdc800->write_urb);
1058 
1059 	kfree (mdc800->irq_urb_buffer);
1060 	kfree (mdc800->write_urb_buffer);
1061 	kfree (mdc800->download_urb_buffer);
1062 
1063 	kfree (mdc800);
1064 	mdc800 = NULL;
1065 }
1066 
1067 module_init (usb_mdc800_init);
1068 module_exit (usb_mdc800_cleanup);
1069 
1070 MODULE_AUTHOR( DRIVER_AUTHOR );
1071 MODULE_DESCRIPTION( DRIVER_DESC );
1072 MODULE_LICENSE("GPL");
1073 
1074