xref: /openbmc/linux/drivers/usb/image/mdc800.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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 Protocoll 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 =		"usb/mdc800%d",
429 	.fops =		&mdc800_device_ops,
430 	.mode =		S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
431 	.minor_base =	MDC800_DEVICE_MINOR_BASE,
432 };
433 
434 
435 /*
436  * Callback to search the Mustek MDC800 on the USB Bus
437  */
438 static int mdc800_usb_probe (struct usb_interface *intf,
439 			       const struct usb_device_id *id)
440 {
441 	int i,j;
442 	struct usb_host_interface *intf_desc;
443 	struct usb_device *dev = interface_to_usbdev (intf);
444 	int irq_interval=0;
445 	int retval;
446 
447 	dbg ("(mdc800_usb_probe) called.");
448 
449 
450 	if (mdc800->dev != NULL)
451 	{
452 		warn ("only one Mustek MDC800 is supported.");
453 		return -ENODEV;
454 	}
455 
456 	if (dev->descriptor.bNumConfigurations != 1)
457 	{
458 		err ("probe fails -> wrong Number of Configuration");
459 		return -ENODEV;
460 	}
461 	intf_desc = intf->cur_altsetting;
462 
463 	if (
464 			( intf_desc->desc.bInterfaceClass != 0xff )
465 		||	( intf_desc->desc.bInterfaceSubClass != 0 )
466 		|| ( intf_desc->desc.bInterfaceProtocol != 0 )
467 		|| ( intf_desc->desc.bNumEndpoints != 4)
468 	)
469 	{
470 		err ("probe fails -> wrong Interface");
471 		return -ENODEV;
472 	}
473 
474 	/* Check the Endpoints */
475 	for (i=0; i<4; i++)
476 	{
477 		mdc800->endpoint[i]=-1;
478 		for (j=0; j<4; j++)
479 		{
480 			if (mdc800_endpoint_equals (&intf_desc->endpoint [j].desc,&mdc800_ed [i]))
481 			{
482 				mdc800->endpoint[i]=intf_desc->endpoint [j].desc.bEndpointAddress ;
483 				if (i==1)
484 				{
485 					irq_interval=intf_desc->endpoint [j].desc.bInterval;
486 				}
487 
488 				continue;
489 			}
490 		}
491 		if (mdc800->endpoint[i] == -1)
492 		{
493 			err ("probe fails -> Wrong Endpoints.");
494 			return -ENODEV;
495 		}
496 	}
497 
498 
499 	info ("Found Mustek MDC800 on USB.");
500 
501 	down (&mdc800->io_lock);
502 
503 	retval = usb_register_dev(intf, &mdc800_class);
504 	if (retval) {
505 		err ("Not able to get a minor for this device.");
506 		return -ENODEV;
507 	}
508 
509 	mdc800->dev=dev;
510 	mdc800->open=0;
511 
512 	/* Setup URB Structs */
513 	usb_fill_int_urb (
514 		mdc800->irq_urb,
515 		mdc800->dev,
516 		usb_rcvintpipe (mdc800->dev,mdc800->endpoint [1]),
517 		mdc800->irq_urb_buffer,
518 		8,
519 		mdc800_usb_irq,
520 		mdc800,
521 		irq_interval
522 	);
523 
524 	usb_fill_bulk_urb (
525 		mdc800->write_urb,
526 		mdc800->dev,
527 		usb_sndbulkpipe (mdc800->dev, mdc800->endpoint[0]),
528 		mdc800->write_urb_buffer,
529 		8,
530 		mdc800_usb_write_notify,
531 		mdc800
532 	);
533 
534 	usb_fill_bulk_urb (
535 		mdc800->download_urb,
536 		mdc800->dev,
537 		usb_rcvbulkpipe (mdc800->dev, mdc800->endpoint [3]),
538 		mdc800->download_urb_buffer,
539 		64,
540 		mdc800_usb_download_notify,
541 		mdc800
542 	);
543 
544 	mdc800->state=READY;
545 
546 	up (&mdc800->io_lock);
547 
548 	usb_set_intfdata(intf, mdc800);
549 	return 0;
550 }
551 
552 
553 /*
554  * Disconnect USB device (maybe the MDC800)
555  */
556 static void mdc800_usb_disconnect (struct usb_interface *intf)
557 {
558 	struct mdc800_data* mdc800 = usb_get_intfdata(intf);
559 
560 	dbg ("(mdc800_usb_disconnect) called");
561 
562 	if (mdc800) {
563 		if (mdc800->state == NOT_CONNECTED)
564 			return;
565 
566 		usb_deregister_dev(intf, &mdc800_class);
567 
568 		mdc800->state=NOT_CONNECTED;
569 
570 		usb_kill_urb(mdc800->irq_urb);
571 		usb_kill_urb(mdc800->write_urb);
572 		usb_kill_urb(mdc800->download_urb);
573 
574 		mdc800->dev = NULL;
575 		usb_set_intfdata(intf, NULL);
576 	}
577 	info ("Mustek MDC800 disconnected from USB.");
578 }
579 
580 
581 /***************************************************************************
582 	The Misc device Part (file_operations)
583 ****************************************************************************/
584 
585 /*
586  * This Function calc the Answersize for a command.
587  */
588 static int mdc800_getAnswerSize (char command)
589 {
590 	switch ((unsigned char) command)
591 	{
592 		case 0x2a:
593 		case 0x49:
594 		case 0x51:
595 		case 0x0d:
596 		case 0x20:
597 		case 0x07:
598 		case 0x01:
599 		case 0x25:
600 		case 0x00:
601 			return 8;
602 
603 		case 0x05:
604 		case 0x3e:
605 			return mdc800->pic_len;
606 
607 		case 0x09:
608 			return 4096;
609 
610 		default:
611 			return 0;
612 	}
613 }
614 
615 
616 /*
617  * Init the device: (1) alloc mem (2) Increase MOD Count ..
618  */
619 static int mdc800_device_open (struct inode* inode, struct file *file)
620 {
621 	int retval=0;
622 	int errn=0;
623 
624 	down (&mdc800->io_lock);
625 
626 	if (mdc800->state == NOT_CONNECTED)
627 	{
628 		errn=-EBUSY;
629 		goto error_out;
630 	}
631 	if (mdc800->open)
632 	{
633 		errn=-EBUSY;
634 		goto error_out;
635 	}
636 
637 	mdc800->in_count=0;
638 	mdc800->out_count=0;
639 	mdc800->out_ptr=0;
640 	mdc800->pic_index=0;
641 	mdc800->pic_len=-1;
642 	mdc800->download_left=0;
643 
644 	mdc800->camera_busy=0;
645 	mdc800->camera_request_ready=0;
646 
647 	retval=0;
648 	mdc800->irq_urb->dev = mdc800->dev;
649 	if (usb_submit_urb (mdc800->irq_urb, GFP_KERNEL))
650 	{
651 		err ("request USB irq fails (submit_retval=%i urb_status=%i).",retval, mdc800->irq_urb->status);
652 		errn = -EIO;
653 		goto error_out;
654 	}
655 
656 	mdc800->open=1;
657 	dbg ("Mustek MDC800 device opened.");
658 
659 error_out:
660 	up (&mdc800->io_lock);
661 	return errn;
662 }
663 
664 
665 /*
666  * Close the Camera and release Memory
667  */
668 static int mdc800_device_release (struct inode* inode, struct file *file)
669 {
670 	int retval=0;
671 	dbg ("Mustek MDC800 device closed.");
672 
673 	down (&mdc800->io_lock);
674 	if (mdc800->open && (mdc800->state != NOT_CONNECTED))
675 	{
676 		usb_kill_urb(mdc800->irq_urb);
677 		usb_kill_urb(mdc800->write_urb);
678 		usb_kill_urb(mdc800->download_urb);
679 		mdc800->open=0;
680 	}
681 	else
682 	{
683 		retval=-EIO;
684 	}
685 
686 	up(&mdc800->io_lock);
687 	return retval;
688 }
689 
690 
691 /*
692  * The Device read callback Function
693  */
694 static ssize_t mdc800_device_read (struct file *file, char __user *buf, size_t len, loff_t *pos)
695 {
696 	size_t left=len, sts=len; /* single transfer size */
697 	char __user *ptr = buf;
698 
699 	down (&mdc800->io_lock);
700 	if (mdc800->state == NOT_CONNECTED)
701 	{
702 		up (&mdc800->io_lock);
703 		return -EBUSY;
704 	}
705 	if (mdc800->state == WORKING)
706 	{
707 		warn ("Illegal State \"working\" reached during read ?!");
708 		up (&mdc800->io_lock);
709 		return -EBUSY;
710 	}
711 	if (!mdc800->open)
712 	{
713 		up (&mdc800->io_lock);
714 		return -EBUSY;
715 	}
716 
717 	while (left)
718 	{
719 		if (signal_pending (current))
720 		{
721 			up (&mdc800->io_lock);
722 			return -EINTR;
723 		}
724 
725 		sts=left > (mdc800->out_count-mdc800->out_ptr)?mdc800->out_count-mdc800->out_ptr:left;
726 
727 		if (sts <= 0)
728 		{
729 			/* Too less Data in buffer */
730 			if (mdc800->state == DOWNLOAD)
731 			{
732 				mdc800->out_count=0;
733 				mdc800->out_ptr=0;
734 
735 				/* Download -> Request new bytes */
736 				mdc800->download_urb->dev = mdc800->dev;
737 				if (usb_submit_urb (mdc800->download_urb, GFP_KERNEL))
738 				{
739 					err ("Can't submit download urb (status=%i)",mdc800->download_urb->status);
740 					up (&mdc800->io_lock);
741 					return len-left;
742 				}
743 				wait_event_timeout(mdc800->download_wait, mdc800->downloaded,
744 										TO_DOWNLOAD_GET_READY*HZ/1000);
745 				mdc800->downloaded = 0;
746 				if (mdc800->download_urb->status != 0)
747 				{
748 					err ("request download-bytes fails (status=%i)",mdc800->download_urb->status);
749 					up (&mdc800->io_lock);
750 					return len-left;
751 				}
752 			}
753 			else
754 			{
755 				/* No more bytes -> that's an error*/
756 				up (&mdc800->io_lock);
757 				return -EIO;
758 			}
759 		}
760 		else
761 		{
762 			/* Copy Bytes */
763 			if (copy_to_user(ptr, &mdc800->out [mdc800->out_ptr],
764 						sts)) {
765 				up(&mdc800->io_lock);
766 				return -EFAULT;
767 			}
768 			ptr+=sts;
769 			left-=sts;
770 			mdc800->out_ptr+=sts;
771 		}
772 	}
773 
774 	up (&mdc800->io_lock);
775 	return len-left;
776 }
777 
778 
779 /*
780  * The Device write callback Function
781  * If a 8Byte Command is received, it will be send to the camera.
782  * After this the driver initiates the request for the answer or
783  * just waits until the camera becomes ready.
784  */
785 static ssize_t mdc800_device_write (struct file *file, const char __user *buf, size_t len, loff_t *pos)
786 {
787 	size_t i=0;
788 
789 	down (&mdc800->io_lock);
790 	if (mdc800->state != READY)
791 	{
792 		up (&mdc800->io_lock);
793 		return -EBUSY;
794 	}
795 	if (!mdc800->open )
796 	{
797 		up (&mdc800->io_lock);
798 		return -EBUSY;
799 	}
800 
801 	while (i<len)
802 	{
803 		unsigned char c;
804 		if (signal_pending (current))
805 		{
806 			up (&mdc800->io_lock);
807 			return -EINTR;
808 		}
809 
810 		if(get_user(c, buf+i))
811 		{
812 			up(&mdc800->io_lock);
813 			return -EFAULT;
814 		}
815 
816 		/* check for command start */
817 		if (c == 0x55)
818 		{
819 			mdc800->in_count=0;
820 			mdc800->out_count=0;
821 			mdc800->out_ptr=0;
822 			mdc800->download_left=0;
823 		}
824 
825 		/* save command byte */
826 		if (mdc800->in_count < 8)
827 		{
828 			mdc800->in[mdc800->in_count] = c;
829 			mdc800->in_count++;
830 		}
831 		else
832 		{
833 			up (&mdc800->io_lock);
834 			return -EIO;
835 		}
836 
837 		/* Command Buffer full ? -> send it to camera */
838 		if (mdc800->in_count == 8)
839 		{
840 			int answersize;
841 
842 			if (mdc800_usb_waitForIRQ (0,TO_GET_READY))
843 			{
844 				err ("Camera didn't get ready.\n");
845 				up (&mdc800->io_lock);
846 				return -EIO;
847 			}
848 
849 			answersize=mdc800_getAnswerSize (mdc800->in[1]);
850 
851 			mdc800->state=WORKING;
852 			memcpy (mdc800->write_urb->transfer_buffer, mdc800->in,8);
853 			mdc800->write_urb->dev = mdc800->dev;
854 			if (usb_submit_urb (mdc800->write_urb, GFP_KERNEL))
855 			{
856 				err ("submitting write urb fails (status=%i)", mdc800->write_urb->status);
857 				up (&mdc800->io_lock);
858 				return -EIO;
859 			}
860 			wait_event_timeout(mdc800->write_wait, mdc800->written, TO_WRITE_GET_READY*HZ/1000);
861 			mdc800->written = 0;
862 			if (mdc800->state == WORKING)
863 			{
864 				usb_kill_urb(mdc800->write_urb);
865 				up (&mdc800->io_lock);
866 				return -EIO;
867 			}
868 
869 			switch ((unsigned char) mdc800->in[1])
870 			{
871 				case 0x05: /* Download Image */
872 				case 0x3e: /* Take shot in Fine Mode (WCam Mode) */
873 					if (mdc800->pic_len < 0)
874 					{
875 						err ("call 0x07 before 0x05,0x3e");
876 						mdc800->state=READY;
877 						up (&mdc800->io_lock);
878 						return -EIO;
879 					}
880 					mdc800->pic_len=-1;
881 
882 				case 0x09: /* Download Thumbnail */
883 					mdc800->download_left=answersize+64;
884 					mdc800->state=DOWNLOAD;
885 					mdc800_usb_waitForIRQ (0,TO_DOWNLOAD_GET_BUSY);
886 					break;
887 
888 
889 				default:
890 					if (answersize)
891 					{
892 
893 						if (mdc800_usb_waitForIRQ (1,TO_READ_FROM_IRQ))
894 						{
895 							err ("requesting answer from irq fails");
896 							up (&mdc800->io_lock);
897 							return -EIO;
898 						}
899 
900 						/* Write dummy data, (this is ugly but part of the USB Protocol */
901 						/* if you use endpoint 1 as bulk and not as irq) */
902 						memcpy (mdc800->out, mdc800->camera_response,8);
903 
904 						/* This is the interpreted answer */
905 						memcpy (&mdc800->out[8], mdc800->camera_response,8);
906 
907 						mdc800->out_ptr=0;
908 						mdc800->out_count=16;
909 
910 						/* Cache the Imagesize, if command was getImageSize */
911 						if (mdc800->in [1] == (char) 0x07)
912 						{
913 							mdc800->pic_len=(int) 65536*(unsigned char) mdc800->camera_response[0]+256*(unsigned char) mdc800->camera_response[1]+(unsigned char) mdc800->camera_response[2];
914 
915 							dbg ("cached imagesize = %i",mdc800->pic_len);
916 						}
917 
918 					}
919 					else
920 					{
921 						if (mdc800_usb_waitForIRQ (0,TO_DEFAULT_COMMAND))
922 						{
923 							err ("Command Timeout.");
924 							up (&mdc800->io_lock);
925 							return -EIO;
926 						}
927 					}
928 					mdc800->state=READY;
929 					break;
930 			}
931 		}
932 		i++;
933 	}
934 	up (&mdc800->io_lock);
935 	return i;
936 }
937 
938 
939 /***************************************************************************
940 	Init and Cleanup this driver (Structs and types)
941 ****************************************************************************/
942 
943 /* File Operations of this drivers */
944 static struct file_operations mdc800_device_ops =
945 {
946 	.owner =	THIS_MODULE,
947 	.read =		mdc800_device_read,
948 	.write =	mdc800_device_write,
949 	.open =		mdc800_device_open,
950 	.release =	mdc800_device_release,
951 };
952 
953 
954 
955 static struct usb_device_id mdc800_table [] = {
956 	{ USB_DEVICE(MDC800_VENDOR_ID, MDC800_PRODUCT_ID) },
957 	{ }						/* Terminating entry */
958 };
959 
960 MODULE_DEVICE_TABLE (usb, mdc800_table);
961 /*
962  * USB Driver Struct for this device
963  */
964 static struct usb_driver mdc800_usb_driver =
965 {
966 	.owner =	THIS_MODULE,
967 	.name =		"mdc800",
968 	.probe =	mdc800_usb_probe,
969 	.disconnect =	mdc800_usb_disconnect,
970 	.id_table =	mdc800_table
971 };
972 
973 
974 
975 /************************************************************************
976 	Init and Cleanup this driver (Main Functions)
977 *************************************************************************/
978 
979 #define try(A)           if (!(A)) goto cleanup_on_fail;
980 
981 static int __init usb_mdc800_init (void)
982 {
983 	int retval = -ENODEV;
984 	/* Allocate Memory */
985 	try (mdc800=kmalloc (sizeof (struct mdc800_data), GFP_KERNEL));
986 
987 	memset(mdc800, 0, sizeof(struct mdc800_data));
988 	mdc800->dev = NULL;
989 	mdc800->open=0;
990 	mdc800->state=NOT_CONNECTED;
991 	init_MUTEX (&mdc800->io_lock);
992 
993 	init_waitqueue_head (&mdc800->irq_wait);
994 	init_waitqueue_head (&mdc800->write_wait);
995 	init_waitqueue_head (&mdc800->download_wait);
996 
997 	mdc800->irq_woken = 0;
998 	mdc800->downloaded = 0;
999 	mdc800->written = 0;
1000 
1001 	try (mdc800->irq_urb_buffer=kmalloc (8, GFP_KERNEL));
1002 	try (mdc800->write_urb_buffer=kmalloc (8, GFP_KERNEL));
1003 	try (mdc800->download_urb_buffer=kmalloc (64, GFP_KERNEL));
1004 
1005 	try (mdc800->irq_urb=usb_alloc_urb (0, GFP_KERNEL));
1006 	try (mdc800->download_urb=usb_alloc_urb (0, GFP_KERNEL));
1007 	try (mdc800->write_urb=usb_alloc_urb (0, GFP_KERNEL));
1008 
1009 	/* Register the driver */
1010 	retval = usb_register(&mdc800_usb_driver);
1011 	if (retval)
1012 		goto cleanup_on_fail;
1013 
1014 	info (DRIVER_VERSION ":" DRIVER_DESC);
1015 
1016 	return 0;
1017 
1018 	/* Clean driver up, when something fails */
1019 
1020 cleanup_on_fail:
1021 
1022 	if (mdc800 != NULL)
1023 	{
1024 		err ("can't alloc memory!");
1025 
1026 		kfree(mdc800->download_urb_buffer);
1027 		kfree(mdc800->write_urb_buffer);
1028 		kfree(mdc800->irq_urb_buffer);
1029 
1030 		usb_free_urb(mdc800->write_urb);
1031 		usb_free_urb(mdc800->download_urb);
1032 		usb_free_urb(mdc800->irq_urb);
1033 
1034 		kfree (mdc800);
1035 	}
1036 	mdc800 = NULL;
1037 	return retval;
1038 }
1039 
1040 
1041 static void __exit usb_mdc800_cleanup (void)
1042 {
1043 	usb_deregister (&mdc800_usb_driver);
1044 
1045 	usb_free_urb (mdc800->irq_urb);
1046 	usb_free_urb (mdc800->download_urb);
1047 	usb_free_urb (mdc800->write_urb);
1048 
1049 	kfree (mdc800->irq_urb_buffer);
1050 	kfree (mdc800->write_urb_buffer);
1051 	kfree (mdc800->download_urb_buffer);
1052 
1053 	kfree (mdc800);
1054 	mdc800 = NULL;
1055 }
1056 
1057 module_init (usb_mdc800_init);
1058 module_exit (usb_mdc800_cleanup);
1059 
1060 MODULE_AUTHOR( DRIVER_AUTHOR );
1061 MODULE_DESCRIPTION( DRIVER_DESC );
1062 MODULE_LICENSE("GPL");
1063 
1064