xref: /linux/drivers/usb/misc/uss720.c (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
1 /*****************************************************************************/
2 
3 /*
4  *	uss720.c  --  USS720 USB Parport Cable.
5  *
6  *	Copyright (C) 1999, 2005, 2010
7  *	    Thomas Sailer (t.sailer@alumni.ethz.ch)
8  *
9  *	This program is free software; you can redistribute it and/or modify
10  *	it under the terms of the GNU General Public License as published by
11  *	the Free Software Foundation; either version 2 of the License, or
12  *	(at your option) any later version.
13  *
14  *	This program is distributed in the hope that it will be useful,
15  *	but WITHOUT ANY WARRANTY; without even the implied warranty of
16  *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  *	GNU General Public License for more details.
18  *
19  *	You should have received a copy of the GNU General Public License
20  *	along with this program; if not, write to the Free Software
21  *	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  *
23  *  Based on parport_pc.c
24  *
25  *  History:
26  *   0.1  04.08.1999  Created
27  *   0.2  07.08.1999  Some fixes mainly suggested by Tim Waugh
28  *		      Interrupt handling currently disabled because
29  *		      usb_request_irq crashes somewhere within ohci.c
30  *		      for no apparent reason (that is for me, anyway)
31  *		      ECP currently untested
32  *   0.3  10.08.1999  fixing merge errors
33  *   0.4  13.08.1999  Added Vendor/Product ID of Brad Hard's cable
34  *   0.5  20.09.1999  usb_control_msg wrapper used
35  *        Nov01.2000  usb_device_table support by Adam J. Richter
36  *        08.04.2001  Identify version on module load.  gb
37  *   0.6  02.09.2005  Fix "scheduling in interrupt" problem by making save/restore
38  *                    context asynchronous
39  *
40  */
41 
42 /*****************************************************************************/
43 
44 #include <linux/module.h>
45 #include <linux/socket.h>
46 #include <linux/parport.h>
47 #include <linux/init.h>
48 #include <linux/usb.h>
49 #include <linux/delay.h>
50 #include <linux/completion.h>
51 #include <linux/kref.h>
52 #include <linux/slab.h>
53 
54 /*
55  * Version Information
56  */
57 #define DRIVER_VERSION "v0.6"
58 #define DRIVER_AUTHOR "Thomas M. Sailer, t.sailer@alumni.ethz.ch"
59 #define DRIVER_DESC "USB Parport Cable driver for Cables using the Lucent Technologies USS720 Chip"
60 
61 /* --------------------------------------------------------------------- */
62 
63 struct parport_uss720_private {
64 	struct usb_device *usbdev;
65 	struct parport *pp;
66 	struct kref ref_count;
67 	__u8 reg[7];  /* USB registers */
68 	struct list_head asynclist;
69 	spinlock_t asynclock;
70 };
71 
72 struct uss720_async_request {
73 	struct parport_uss720_private *priv;
74 	struct kref ref_count;
75 	struct list_head asynclist;
76 	struct completion compl;
77 	struct urb *urb;
78 	struct usb_ctrlrequest *dr;
79 	__u8 reg[7];
80 };
81 
82 /* --------------------------------------------------------------------- */
83 
84 static void destroy_priv(struct kref *kref)
85 {
86 	struct parport_uss720_private *priv = container_of(kref, struct parport_uss720_private, ref_count);
87 
88 	dev_dbg(&priv->usbdev->dev, "destroying priv datastructure\n");
89 	usb_put_dev(priv->usbdev);
90 	kfree(priv);
91 }
92 
93 static void destroy_async(struct kref *kref)
94 {
95 	struct uss720_async_request *rq = container_of(kref, struct uss720_async_request, ref_count);
96 	struct parport_uss720_private *priv = rq->priv;
97 	unsigned long flags;
98 
99 	if (likely(rq->urb))
100 		usb_free_urb(rq->urb);
101 	kfree(rq->dr);
102 	spin_lock_irqsave(&priv->asynclock, flags);
103 	list_del_init(&rq->asynclist);
104 	spin_unlock_irqrestore(&priv->asynclock, flags);
105 	kfree(rq);
106 	kref_put(&priv->ref_count, destroy_priv);
107 }
108 
109 /* --------------------------------------------------------------------- */
110 
111 static void async_complete(struct urb *urb)
112 {
113 	struct uss720_async_request *rq;
114 	struct parport *pp;
115 	struct parport_uss720_private *priv;
116 	int status = urb->status;
117 
118 	rq = urb->context;
119 	priv = rq->priv;
120 	pp = priv->pp;
121 	if (status) {
122 		dev_err(&urb->dev->dev, "async_complete: urb error %d\n",
123 			status);
124 	} else if (rq->dr->bRequest == 3) {
125 		memcpy(priv->reg, rq->reg, sizeof(priv->reg));
126 #if 0
127 		dev_dbg(&priv->usbdev->dev, "async_complete regs %7ph\n",
128 			priv->reg);
129 #endif
130 		/* if nAck interrupts are enabled and we have an interrupt, call the interrupt procedure */
131 		if (rq->reg[2] & rq->reg[1] & 0x10 && pp)
132 			parport_generic_irq(pp);
133 	}
134 	complete(&rq->compl);
135 	kref_put(&rq->ref_count, destroy_async);
136 }
137 
138 static struct uss720_async_request *submit_async_request(struct parport_uss720_private *priv,
139 							 __u8 request, __u8 requesttype, __u16 value, __u16 index,
140 							 gfp_t mem_flags)
141 {
142 	struct usb_device *usbdev;
143 	struct uss720_async_request *rq;
144 	unsigned long flags;
145 	int ret;
146 
147 	if (!priv)
148 		return NULL;
149 	usbdev = priv->usbdev;
150 	if (!usbdev)
151 		return NULL;
152 	rq = kzalloc(sizeof(struct uss720_async_request), mem_flags);
153 	if (!rq)
154 		return NULL;
155 	kref_init(&rq->ref_count);
156 	INIT_LIST_HEAD(&rq->asynclist);
157 	init_completion(&rq->compl);
158 	kref_get(&priv->ref_count);
159 	rq->priv = priv;
160 	rq->urb = usb_alloc_urb(0, mem_flags);
161 	if (!rq->urb) {
162 		kref_put(&rq->ref_count, destroy_async);
163 		return NULL;
164 	}
165 	rq->dr = kmalloc(sizeof(*rq->dr), mem_flags);
166 	if (!rq->dr) {
167 		kref_put(&rq->ref_count, destroy_async);
168 		return NULL;
169 	}
170 	rq->dr->bRequestType = requesttype;
171 	rq->dr->bRequest = request;
172 	rq->dr->wValue = cpu_to_le16(value);
173 	rq->dr->wIndex = cpu_to_le16(index);
174 	rq->dr->wLength = cpu_to_le16((request == 3) ? sizeof(rq->reg) : 0);
175 	usb_fill_control_urb(rq->urb, usbdev, (requesttype & 0x80) ? usb_rcvctrlpipe(usbdev, 0) : usb_sndctrlpipe(usbdev, 0),
176 			     (unsigned char *)rq->dr,
177 			     (request == 3) ? rq->reg : NULL, (request == 3) ? sizeof(rq->reg) : 0, async_complete, rq);
178 	/* rq->urb->transfer_flags |= URB_ASYNC_UNLINK; */
179 	spin_lock_irqsave(&priv->asynclock, flags);
180 	list_add_tail(&rq->asynclist, &priv->asynclist);
181 	spin_unlock_irqrestore(&priv->asynclock, flags);
182 	kref_get(&rq->ref_count);
183 	ret = usb_submit_urb(rq->urb, mem_flags);
184 	if (!ret)
185 		return rq;
186 	destroy_async(&rq->ref_count);
187 	dev_err(&usbdev->dev, "submit_async_request submit_urb failed with %d\n", ret);
188 	return NULL;
189 }
190 
191 static unsigned int kill_all_async_requests_priv(struct parport_uss720_private *priv)
192 {
193 	struct uss720_async_request *rq;
194 	unsigned long flags;
195 	unsigned int ret = 0;
196 
197 	spin_lock_irqsave(&priv->asynclock, flags);
198 	list_for_each_entry(rq, &priv->asynclist, asynclist) {
199 		usb_unlink_urb(rq->urb);
200 		ret++;
201 	}
202 	spin_unlock_irqrestore(&priv->asynclock, flags);
203 	return ret;
204 }
205 
206 /* --------------------------------------------------------------------- */
207 
208 static int get_1284_register(struct parport *pp, unsigned char reg, unsigned char *val, gfp_t mem_flags)
209 {
210 	struct parport_uss720_private *priv;
211 	struct uss720_async_request *rq;
212 	static const unsigned char regindex[9] = {
213 		4, 0, 1, 5, 5, 0, 2, 3, 6
214 	};
215 	int ret;
216 
217 	if (!pp)
218 		return -EIO;
219 	priv = pp->private_data;
220 	rq = submit_async_request(priv, 3, 0xc0, ((unsigned int)reg) << 8, 0, mem_flags);
221 	if (!rq) {
222 		dev_err(&priv->usbdev->dev, "get_1284_register(%u) failed",
223 			(unsigned int)reg);
224 		return -EIO;
225 	}
226 	if (!val) {
227 		kref_put(&rq->ref_count, destroy_async);
228 		return 0;
229 	}
230 	if (wait_for_completion_timeout(&rq->compl, HZ)) {
231 		ret = rq->urb->status;
232 		*val = priv->reg[(reg >= 9) ? 0 : regindex[reg]];
233 		if (ret)
234 			printk(KERN_WARNING "get_1284_register: "
235 			       "usb error %d\n", ret);
236 		kref_put(&rq->ref_count, destroy_async);
237 		return ret;
238 	}
239 	printk(KERN_WARNING "get_1284_register timeout\n");
240 	kill_all_async_requests_priv(priv);
241 	return -EIO;
242 }
243 
244 static int set_1284_register(struct parport *pp, unsigned char reg, unsigned char val, gfp_t mem_flags)
245 {
246 	struct parport_uss720_private *priv;
247 	struct uss720_async_request *rq;
248 
249 	if (!pp)
250 		return -EIO;
251 	priv = pp->private_data;
252 	rq = submit_async_request(priv, 4, 0x40, (((unsigned int)reg) << 8) | val, 0, mem_flags);
253 	if (!rq) {
254 		dev_err(&priv->usbdev->dev, "set_1284_register(%u,%u) failed",
255 			(unsigned int)reg, (unsigned int)val);
256 		return -EIO;
257 	}
258 	kref_put(&rq->ref_count, destroy_async);
259 	return 0;
260 }
261 
262 /* --------------------------------------------------------------------- */
263 
264 /* ECR modes */
265 #define ECR_SPP 00
266 #define ECR_PS2 01
267 #define ECR_PPF 02
268 #define ECR_ECP 03
269 #define ECR_EPP 04
270 
271 /* Safely change the mode bits in the ECR */
272 static int change_mode(struct parport *pp, int m)
273 {
274 	struct parport_uss720_private *priv = pp->private_data;
275 	int mode;
276 	__u8 reg;
277 
278 	if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
279 		return -EIO;
280 	/* Bits <7:5> contain the mode. */
281 	mode = (priv->reg[2] >> 5) & 0x7;
282 	if (mode == m)
283 		return 0;
284 	/* We have to go through mode 000 or 001 */
285 	if (mode > ECR_PS2 && m > ECR_PS2)
286 		if (change_mode(pp, ECR_PS2))
287 			return -EIO;
288 
289 	if (m <= ECR_PS2 && !(priv->reg[1] & 0x20)) {
290 		/* This mode resets the FIFO, so we may
291 		 * have to wait for it to drain first. */
292 		unsigned long expire = jiffies + pp->physport->cad->timeout;
293 		switch (mode) {
294 		case ECR_PPF: /* Parallel Port FIFO mode */
295 		case ECR_ECP: /* ECP Parallel Port mode */
296 			/* Poll slowly. */
297 			for (;;) {
298 				if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
299 					return -EIO;
300 				if (priv->reg[2] & 0x01)
301 					break;
302 				if (time_after_eq (jiffies, expire))
303 					/* The FIFO is stuck. */
304 					return -EBUSY;
305 				msleep_interruptible(10);
306 				if (signal_pending (current))
307 					break;
308 			}
309 		}
310 	}
311 	/* Set the mode. */
312 	if (set_1284_register(pp, 6, m << 5, GFP_KERNEL))
313 		return -EIO;
314 	if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
315 		return -EIO;
316 	return 0;
317 }
318 
319 /*
320  * Clear TIMEOUT BIT in EPP MODE
321  */
322 static int clear_epp_timeout(struct parport *pp)
323 {
324 	unsigned char stat;
325 
326 	if (get_1284_register(pp, 1, &stat, GFP_KERNEL))
327 		return 1;
328 	return stat & 1;
329 }
330 
331 /*
332  * Access functions.
333  */
334 #if 0
335 static int uss720_irq(int usbstatus, void *buffer, int len, void *dev_id)
336 {
337 	struct parport *pp = (struct parport *)dev_id;
338 	struct parport_uss720_private *priv = pp->private_data;
339 
340 	if (usbstatus != 0 || len < 4 || !buffer)
341 		return 1;
342 	memcpy(priv->reg, buffer, 4);
343 	/* if nAck interrupts are enabled and we have an interrupt, call the interrupt procedure */
344 	if (priv->reg[2] & priv->reg[1] & 0x10)
345 		parport_generic_irq(pp);
346 	return 1;
347 }
348 #endif
349 
350 static void parport_uss720_write_data(struct parport *pp, unsigned char d)
351 {
352 	set_1284_register(pp, 0, d, GFP_KERNEL);
353 }
354 
355 static unsigned char parport_uss720_read_data(struct parport *pp)
356 {
357 	unsigned char ret;
358 
359 	if (get_1284_register(pp, 0, &ret, GFP_KERNEL))
360 		return 0;
361 	return ret;
362 }
363 
364 static void parport_uss720_write_control(struct parport *pp, unsigned char d)
365 {
366 	struct parport_uss720_private *priv = pp->private_data;
367 
368 	d = (d & 0xf) | (priv->reg[1] & 0xf0);
369 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
370 		return;
371 	priv->reg[1] = d;
372 }
373 
374 static unsigned char parport_uss720_read_control(struct parport *pp)
375 {
376 	struct parport_uss720_private *priv = pp->private_data;
377 	return priv->reg[1] & 0xf; /* Use soft copy */
378 }
379 
380 static unsigned char parport_uss720_frob_control(struct parport *pp, unsigned char mask, unsigned char val)
381 {
382 	struct parport_uss720_private *priv = pp->private_data;
383 	unsigned char d;
384 
385 	mask &= 0x0f;
386 	val &= 0x0f;
387 	d = (priv->reg[1] & (~mask)) ^ val;
388 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
389 		return 0;
390 	priv->reg[1] = d;
391 	return d & 0xf;
392 }
393 
394 static unsigned char parport_uss720_read_status(struct parport *pp)
395 {
396 	unsigned char ret;
397 
398 	if (get_1284_register(pp, 1, &ret, GFP_KERNEL))
399 		return 0;
400 	return ret & 0xf8;
401 }
402 
403 static void parport_uss720_disable_irq(struct parport *pp)
404 {
405 	struct parport_uss720_private *priv = pp->private_data;
406 	unsigned char d;
407 
408 	d = priv->reg[1] & ~0x10;
409 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
410 		return;
411 	priv->reg[1] = d;
412 }
413 
414 static void parport_uss720_enable_irq(struct parport *pp)
415 {
416 	struct parport_uss720_private *priv = pp->private_data;
417 	unsigned char d;
418 
419 	d = priv->reg[1] | 0x10;
420 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
421 		return;
422 	priv->reg[1] = d;
423 }
424 
425 static void parport_uss720_data_forward (struct parport *pp)
426 {
427 	struct parport_uss720_private *priv = pp->private_data;
428 	unsigned char d;
429 
430 	d = priv->reg[1] & ~0x20;
431 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
432 		return;
433 	priv->reg[1] = d;
434 }
435 
436 static void parport_uss720_data_reverse (struct parport *pp)
437 {
438 	struct parport_uss720_private *priv = pp->private_data;
439 	unsigned char d;
440 
441 	d = priv->reg[1] | 0x20;
442 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
443 		return;
444 	priv->reg[1] = d;
445 }
446 
447 static void parport_uss720_init_state(struct pardevice *dev, struct parport_state *s)
448 {
449 	s->u.pc.ctr = 0xc | (dev->irq_func ? 0x10 : 0x0);
450 	s->u.pc.ecr = 0x24;
451 }
452 
453 static void parport_uss720_save_state(struct parport *pp, struct parport_state *s)
454 {
455 	struct parport_uss720_private *priv = pp->private_data;
456 
457 #if 0
458 	if (get_1284_register(pp, 2, NULL, GFP_ATOMIC))
459 		return;
460 #endif
461 	s->u.pc.ctr = priv->reg[1];
462 	s->u.pc.ecr = priv->reg[2];
463 }
464 
465 static void parport_uss720_restore_state(struct parport *pp, struct parport_state *s)
466 {
467 	struct parport_uss720_private *priv = pp->private_data;
468 
469 	set_1284_register(pp, 2, s->u.pc.ctr, GFP_ATOMIC);
470 	set_1284_register(pp, 6, s->u.pc.ecr, GFP_ATOMIC);
471 	get_1284_register(pp, 2, NULL, GFP_ATOMIC);
472 	priv->reg[1] = s->u.pc.ctr;
473 	priv->reg[2] = s->u.pc.ecr;
474 }
475 
476 static size_t parport_uss720_epp_read_data(struct parport *pp, void *buf, size_t length, int flags)
477 {
478 	struct parport_uss720_private *priv = pp->private_data;
479 	size_t got = 0;
480 
481 	if (change_mode(pp, ECR_EPP))
482 		return 0;
483 	for (; got < length; got++) {
484 		if (get_1284_register(pp, 4, (char *)buf, GFP_KERNEL))
485 			break;
486 		buf++;
487 		if (priv->reg[0] & 0x01) {
488 			clear_epp_timeout(pp);
489 			break;
490 		}
491 	}
492 	change_mode(pp, ECR_PS2);
493 	return got;
494 }
495 
496 static size_t parport_uss720_epp_write_data(struct parport *pp, const void *buf, size_t length, int flags)
497 {
498 #if 0
499 	struct parport_uss720_private *priv = pp->private_data;
500 	size_t written = 0;
501 
502 	if (change_mode(pp, ECR_EPP))
503 		return 0;
504 	for (; written < length; written++) {
505 		if (set_1284_register(pp, 4, (char *)buf, GFP_KERNEL))
506 			break;
507 		((char*)buf)++;
508 		if (get_1284_register(pp, 1, NULL, GFP_KERNEL))
509 			break;
510 		if (priv->reg[0] & 0x01) {
511 			clear_epp_timeout(pp);
512 			break;
513 		}
514 	}
515 	change_mode(pp, ECR_PS2);
516 	return written;
517 #else
518 	struct parport_uss720_private *priv = pp->private_data;
519 	struct usb_device *usbdev = priv->usbdev;
520 	int rlen;
521 	int i;
522 
523 	if (!usbdev)
524 		return 0;
525 	if (change_mode(pp, ECR_EPP))
526 		return 0;
527 	i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buf, length, &rlen, 20000);
528 	if (i)
529 		printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %Zu rlen %u\n", buf, length, rlen);
530 	change_mode(pp, ECR_PS2);
531 	return rlen;
532 #endif
533 }
534 
535 static size_t parport_uss720_epp_read_addr(struct parport *pp, void *buf, size_t length, int flags)
536 {
537 	struct parport_uss720_private *priv = pp->private_data;
538 	size_t got = 0;
539 
540 	if (change_mode(pp, ECR_EPP))
541 		return 0;
542 	for (; got < length; got++) {
543 		if (get_1284_register(pp, 3, (char *)buf, GFP_KERNEL))
544 			break;
545 		buf++;
546 		if (priv->reg[0] & 0x01) {
547 			clear_epp_timeout(pp);
548 			break;
549 		}
550 	}
551 	change_mode(pp, ECR_PS2);
552 	return got;
553 }
554 
555 static size_t parport_uss720_epp_write_addr(struct parport *pp, const void *buf, size_t length, int flags)
556 {
557 	struct parport_uss720_private *priv = pp->private_data;
558 	size_t written = 0;
559 
560 	if (change_mode(pp, ECR_EPP))
561 		return 0;
562 	for (; written < length; written++) {
563 		if (set_1284_register(pp, 3, *(char *)buf, GFP_KERNEL))
564 			break;
565 		buf++;
566 		if (get_1284_register(pp, 1, NULL, GFP_KERNEL))
567 			break;
568 		if (priv->reg[0] & 0x01) {
569 			clear_epp_timeout(pp);
570 			break;
571 		}
572 	}
573 	change_mode(pp, ECR_PS2);
574 	return written;
575 }
576 
577 static size_t parport_uss720_ecp_write_data(struct parport *pp, const void *buffer, size_t len, int flags)
578 {
579 	struct parport_uss720_private *priv = pp->private_data;
580 	struct usb_device *usbdev = priv->usbdev;
581 	int rlen;
582 	int i;
583 
584 	if (!usbdev)
585 		return 0;
586 	if (change_mode(pp, ECR_ECP))
587 		return 0;
588 	i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buffer, len, &rlen, 20000);
589 	if (i)
590 		printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %Zu rlen %u\n", buffer, len, rlen);
591 	change_mode(pp, ECR_PS2);
592 	return rlen;
593 }
594 
595 static size_t parport_uss720_ecp_read_data(struct parport *pp, void *buffer, size_t len, int flags)
596 {
597 	struct parport_uss720_private *priv = pp->private_data;
598 	struct usb_device *usbdev = priv->usbdev;
599 	int rlen;
600 	int i;
601 
602 	if (!usbdev)
603 		return 0;
604 	if (change_mode(pp, ECR_ECP))
605 		return 0;
606 	i = usb_bulk_msg(usbdev, usb_rcvbulkpipe(usbdev, 2), buffer, len, &rlen, 20000);
607 	if (i)
608 		printk(KERN_ERR "uss720: recvbulk ep 2 buf %p len %Zu rlen %u\n", buffer, len, rlen);
609 	change_mode(pp, ECR_PS2);
610 	return rlen;
611 }
612 
613 static size_t parport_uss720_ecp_write_addr(struct parport *pp, const void *buffer, size_t len, int flags)
614 {
615 	size_t written = 0;
616 
617 	if (change_mode(pp, ECR_ECP))
618 		return 0;
619 	for (; written < len; written++) {
620 		if (set_1284_register(pp, 5, *(char *)buffer, GFP_KERNEL))
621 			break;
622 		buffer++;
623 	}
624 	change_mode(pp, ECR_PS2);
625 	return written;
626 }
627 
628 static size_t parport_uss720_write_compat(struct parport *pp, const void *buffer, size_t len, int flags)
629 {
630 	struct parport_uss720_private *priv = pp->private_data;
631 	struct usb_device *usbdev = priv->usbdev;
632 	int rlen;
633 	int i;
634 
635 	if (!usbdev)
636 		return 0;
637 	if (change_mode(pp, ECR_PPF))
638 		return 0;
639 	i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buffer, len, &rlen, 20000);
640 	if (i)
641 		printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %Zu rlen %u\n", buffer, len, rlen);
642 	change_mode(pp, ECR_PS2);
643 	return rlen;
644 }
645 
646 /* --------------------------------------------------------------------- */
647 
648 static struct parport_operations parport_uss720_ops =
649 {
650 	.owner =		THIS_MODULE,
651 	.write_data =		parport_uss720_write_data,
652 	.read_data =		parport_uss720_read_data,
653 
654 	.write_control =	parport_uss720_write_control,
655 	.read_control =		parport_uss720_read_control,
656 	.frob_control =		parport_uss720_frob_control,
657 
658 	.read_status =		parport_uss720_read_status,
659 
660 	.enable_irq =		parport_uss720_enable_irq,
661 	.disable_irq =		parport_uss720_disable_irq,
662 
663 	.data_forward =		parport_uss720_data_forward,
664 	.data_reverse =		parport_uss720_data_reverse,
665 
666 	.init_state =		parport_uss720_init_state,
667 	.save_state =		parport_uss720_save_state,
668 	.restore_state =	parport_uss720_restore_state,
669 
670 	.epp_write_data =	parport_uss720_epp_write_data,
671 	.epp_read_data =	parport_uss720_epp_read_data,
672 	.epp_write_addr =	parport_uss720_epp_write_addr,
673 	.epp_read_addr =	parport_uss720_epp_read_addr,
674 
675 	.ecp_write_data =	parport_uss720_ecp_write_data,
676 	.ecp_read_data =	parport_uss720_ecp_read_data,
677 	.ecp_write_addr =	parport_uss720_ecp_write_addr,
678 
679 	.compat_write_data =	parport_uss720_write_compat,
680 	.nibble_read_data =	parport_ieee1284_read_nibble,
681 	.byte_read_data =	parport_ieee1284_read_byte,
682 };
683 
684 /* --------------------------------------------------------------------- */
685 
686 static int uss720_probe(struct usb_interface *intf,
687 			const struct usb_device_id *id)
688 {
689 	struct usb_device *usbdev = usb_get_dev(interface_to_usbdev(intf));
690 	struct usb_host_interface *interface;
691 	struct usb_host_endpoint *endpoint;
692 	struct parport_uss720_private *priv;
693 	struct parport *pp;
694 	unsigned char reg;
695 	int i;
696 
697 	dev_dbg(&intf->dev, "probe: vendor id 0x%x, device id 0x%x\n",
698 		le16_to_cpu(usbdev->descriptor.idVendor),
699 		le16_to_cpu(usbdev->descriptor.idProduct));
700 
701 	/* our known interfaces have 3 alternate settings */
702 	if (intf->num_altsetting != 3) {
703 		usb_put_dev(usbdev);
704 		return -ENODEV;
705 	}
706 	i = usb_set_interface(usbdev, intf->altsetting->desc.bInterfaceNumber, 2);
707 	dev_dbg(&intf->dev, "set interface result %d\n", i);
708 
709 	interface = intf->cur_altsetting;
710 
711 	/*
712 	 * Allocate parport interface
713 	 */
714 	priv = kzalloc(sizeof(struct parport_uss720_private), GFP_KERNEL);
715 	if (!priv) {
716 		usb_put_dev(usbdev);
717 		return -ENOMEM;
718 	}
719 	priv->pp = NULL;
720 	priv->usbdev = usbdev;
721 	kref_init(&priv->ref_count);
722 	spin_lock_init(&priv->asynclock);
723 	INIT_LIST_HEAD(&priv->asynclist);
724 	pp = parport_register_port(0, PARPORT_IRQ_NONE, PARPORT_DMA_NONE, &parport_uss720_ops);
725 	if (!pp) {
726 		printk(KERN_WARNING "uss720: could not register parport\n");
727 		goto probe_abort;
728 	}
729 
730 	priv->pp = pp;
731 	pp->private_data = priv;
732 	pp->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_TRISTATE | PARPORT_MODE_EPP | PARPORT_MODE_ECP | PARPORT_MODE_COMPAT;
733 
734 	/* set the USS720 control register to manual mode, no ECP compression, enable all ints */
735 	set_1284_register(pp, 7, 0x00, GFP_KERNEL);
736 	set_1284_register(pp, 6, 0x30, GFP_KERNEL);  /* PS/2 mode */
737 	set_1284_register(pp, 2, 0x0c, GFP_KERNEL);
738 	/* debugging */
739 	get_1284_register(pp, 0, &reg, GFP_KERNEL);
740 	dev_dbg(&intf->dev, "reg: %7ph\n", priv->reg);
741 
742 	endpoint = &interface->endpoint[2];
743 	dev_dbg(&intf->dev, "epaddr %d interval %d\n",
744 		endpoint->desc.bEndpointAddress, endpoint->desc.bInterval);
745 	parport_announce_port(pp);
746 
747 	usb_set_intfdata(intf, pp);
748 	return 0;
749 
750 probe_abort:
751 	kill_all_async_requests_priv(priv);
752 	kref_put(&priv->ref_count, destroy_priv);
753 	return -ENODEV;
754 }
755 
756 static void uss720_disconnect(struct usb_interface *intf)
757 {
758 	struct parport *pp = usb_get_intfdata(intf);
759 	struct parport_uss720_private *priv;
760 	struct usb_device *usbdev;
761 
762 	dev_dbg(&intf->dev, "disconnect\n");
763 	usb_set_intfdata(intf, NULL);
764 	if (pp) {
765 		priv = pp->private_data;
766 		usbdev = priv->usbdev;
767 		priv->usbdev = NULL;
768 		priv->pp = NULL;
769 		dev_dbg(&intf->dev, "parport_remove_port\n");
770 		parport_remove_port(pp);
771 		parport_put_port(pp);
772 		kill_all_async_requests_priv(priv);
773 		kref_put(&priv->ref_count, destroy_priv);
774 	}
775 	dev_dbg(&intf->dev, "disconnect done\n");
776 }
777 
778 /* table of cables that work through this driver */
779 static const struct usb_device_id uss720_table[] = {
780 	{ USB_DEVICE(0x047e, 0x1001) },
781 	{ USB_DEVICE(0x0557, 0x2001) },
782 	{ USB_DEVICE(0x0729, 0x1284) },
783 	{ USB_DEVICE(0x1293, 0x0002) },
784 	{ USB_DEVICE(0x050d, 0x0002) },
785 	{ }						/* Terminating entry */
786 };
787 
788 MODULE_DEVICE_TABLE (usb, uss720_table);
789 
790 
791 static struct usb_driver uss720_driver = {
792 	.name =		"uss720",
793 	.probe =	uss720_probe,
794 	.disconnect =	uss720_disconnect,
795 	.id_table =	uss720_table,
796 };
797 
798 /* --------------------------------------------------------------------- */
799 
800 MODULE_AUTHOR(DRIVER_AUTHOR);
801 MODULE_DESCRIPTION(DRIVER_DESC);
802 MODULE_LICENSE("GPL");
803 
804 static int __init uss720_init(void)
805 {
806 	int retval;
807 	retval = usb_register(&uss720_driver);
808 	if (retval)
809 		goto out;
810 
811 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
812 	       DRIVER_DESC "\n");
813 	printk(KERN_INFO KBUILD_MODNAME ": NOTE: this is a special purpose "
814 	       "driver to allow nonstandard\n");
815 	printk(KERN_INFO KBUILD_MODNAME ": protocols (eg. bitbang) over "
816 	       "USS720 usb to parallel cables\n");
817 	printk(KERN_INFO KBUILD_MODNAME ": If you just want to connect to a "
818 	       "printer, use usblp instead\n");
819 out:
820 	return retval;
821 }
822 
823 static void __exit uss720_cleanup(void)
824 {
825 	usb_deregister(&uss720_driver);
826 }
827 
828 module_init(uss720_init);
829 module_exit(uss720_cleanup);
830 
831 /* --------------------------------------------------------------------- */
832