xref: /linux/drivers/usb/misc/uss720.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
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 #include <linux/sched/signal.h>
54 
55 /*
56  * Version Information
57  */
58 #define DRIVER_VERSION "v0.6"
59 #define DRIVER_AUTHOR "Thomas M. Sailer, t.sailer@alumni.ethz.ch"
60 #define DRIVER_DESC "USB Parport Cable driver for Cables using the Lucent Technologies USS720 Chip"
61 
62 /* --------------------------------------------------------------------- */
63 
64 struct parport_uss720_private {
65 	struct usb_device *usbdev;
66 	struct parport *pp;
67 	struct kref ref_count;
68 	__u8 reg[7];  /* USB registers */
69 	struct list_head asynclist;
70 	spinlock_t asynclock;
71 };
72 
73 struct uss720_async_request {
74 	struct parport_uss720_private *priv;
75 	struct kref ref_count;
76 	struct list_head asynclist;
77 	struct completion compl;
78 	struct urb *urb;
79 	struct usb_ctrlrequest *dr;
80 	__u8 reg[7];
81 };
82 
83 /* --------------------------------------------------------------------- */
84 
85 static void destroy_priv(struct kref *kref)
86 {
87 	struct parport_uss720_private *priv = container_of(kref, struct parport_uss720_private, ref_count);
88 
89 	dev_dbg(&priv->usbdev->dev, "destroying priv datastructure\n");
90 	usb_put_dev(priv->usbdev);
91 	kfree(priv);
92 }
93 
94 static void destroy_async(struct kref *kref)
95 {
96 	struct uss720_async_request *rq = container_of(kref, struct uss720_async_request, ref_count);
97 	struct parport_uss720_private *priv = rq->priv;
98 	unsigned long flags;
99 
100 	if (likely(rq->urb))
101 		usb_free_urb(rq->urb);
102 	kfree(rq->dr);
103 	spin_lock_irqsave(&priv->asynclock, flags);
104 	list_del_init(&rq->asynclist);
105 	spin_unlock_irqrestore(&priv->asynclock, flags);
106 	kfree(rq);
107 	kref_put(&priv->ref_count, destroy_priv);
108 }
109 
110 /* --------------------------------------------------------------------- */
111 
112 static void async_complete(struct urb *urb)
113 {
114 	struct uss720_async_request *rq;
115 	struct parport *pp;
116 	struct parport_uss720_private *priv;
117 	int status = urb->status;
118 
119 	rq = urb->context;
120 	priv = rq->priv;
121 	pp = priv->pp;
122 	if (status) {
123 		dev_err(&urb->dev->dev, "async_complete: urb error %d\n",
124 			status);
125 	} else if (rq->dr->bRequest == 3) {
126 		memcpy(priv->reg, rq->reg, sizeof(priv->reg));
127 #if 0
128 		dev_dbg(&priv->usbdev->dev, "async_complete regs %7ph\n",
129 			priv->reg);
130 #endif
131 		/* if nAck interrupts are enabled and we have an interrupt, call the interrupt procedure */
132 		if (rq->reg[2] & rq->reg[1] & 0x10 && pp)
133 			parport_generic_irq(pp);
134 	}
135 	complete(&rq->compl);
136 	kref_put(&rq->ref_count, destroy_async);
137 }
138 
139 static struct uss720_async_request *submit_async_request(struct parport_uss720_private *priv,
140 							 __u8 request, __u8 requesttype, __u16 value, __u16 index,
141 							 gfp_t mem_flags)
142 {
143 	struct usb_device *usbdev;
144 	struct uss720_async_request *rq;
145 	unsigned long flags;
146 	int ret;
147 
148 	if (!priv)
149 		return NULL;
150 	usbdev = priv->usbdev;
151 	if (!usbdev)
152 		return NULL;
153 	rq = kzalloc(sizeof(struct uss720_async_request), mem_flags);
154 	if (!rq)
155 		return NULL;
156 	kref_init(&rq->ref_count);
157 	INIT_LIST_HEAD(&rq->asynclist);
158 	init_completion(&rq->compl);
159 	kref_get(&priv->ref_count);
160 	rq->priv = priv;
161 	rq->urb = usb_alloc_urb(0, mem_flags);
162 	if (!rq->urb) {
163 		kref_put(&rq->ref_count, destroy_async);
164 		return NULL;
165 	}
166 	rq->dr = kmalloc(sizeof(*rq->dr), mem_flags);
167 	if (!rq->dr) {
168 		kref_put(&rq->ref_count, destroy_async);
169 		return NULL;
170 	}
171 	rq->dr->bRequestType = requesttype;
172 	rq->dr->bRequest = request;
173 	rq->dr->wValue = cpu_to_le16(value);
174 	rq->dr->wIndex = cpu_to_le16(index);
175 	rq->dr->wLength = cpu_to_le16((request == 3) ? sizeof(rq->reg) : 0);
176 	usb_fill_control_urb(rq->urb, usbdev, (requesttype & 0x80) ? usb_rcvctrlpipe(usbdev, 0) : usb_sndctrlpipe(usbdev, 0),
177 			     (unsigned char *)rq->dr,
178 			     (request == 3) ? rq->reg : NULL, (request == 3) ? sizeof(rq->reg) : 0, async_complete, rq);
179 	/* rq->urb->transfer_flags |= URB_ASYNC_UNLINK; */
180 	spin_lock_irqsave(&priv->asynclock, flags);
181 	list_add_tail(&rq->asynclist, &priv->asynclist);
182 	spin_unlock_irqrestore(&priv->asynclock, flags);
183 	kref_get(&rq->ref_count);
184 	ret = usb_submit_urb(rq->urb, mem_flags);
185 	if (!ret)
186 		return rq;
187 	destroy_async(&rq->ref_count);
188 	dev_err(&usbdev->dev, "submit_async_request submit_urb failed with %d\n", ret);
189 	return NULL;
190 }
191 
192 static unsigned int kill_all_async_requests_priv(struct parport_uss720_private *priv)
193 {
194 	struct uss720_async_request *rq;
195 	unsigned long flags;
196 	unsigned int ret = 0;
197 
198 	spin_lock_irqsave(&priv->asynclock, flags);
199 	list_for_each_entry(rq, &priv->asynclist, asynclist) {
200 		usb_unlink_urb(rq->urb);
201 		ret++;
202 	}
203 	spin_unlock_irqrestore(&priv->asynclock, flags);
204 	return ret;
205 }
206 
207 /* --------------------------------------------------------------------- */
208 
209 static int get_1284_register(struct parport *pp, unsigned char reg, unsigned char *val, gfp_t mem_flags)
210 {
211 	struct parport_uss720_private *priv;
212 	struct uss720_async_request *rq;
213 	static const unsigned char regindex[9] = {
214 		4, 0, 1, 5, 5, 0, 2, 3, 6
215 	};
216 	int ret;
217 
218 	if (!pp)
219 		return -EIO;
220 	priv = pp->private_data;
221 	rq = submit_async_request(priv, 3, 0xc0, ((unsigned int)reg) << 8, 0, mem_flags);
222 	if (!rq) {
223 		dev_err(&priv->usbdev->dev, "get_1284_register(%u) failed",
224 			(unsigned int)reg);
225 		return -EIO;
226 	}
227 	if (!val) {
228 		kref_put(&rq->ref_count, destroy_async);
229 		return 0;
230 	}
231 	if (wait_for_completion_timeout(&rq->compl, HZ)) {
232 		ret = rq->urb->status;
233 		*val = priv->reg[(reg >= 9) ? 0 : regindex[reg]];
234 		if (ret)
235 			printk(KERN_WARNING "get_1284_register: "
236 			       "usb error %d\n", ret);
237 		kref_put(&rq->ref_count, destroy_async);
238 		return ret;
239 	}
240 	printk(KERN_WARNING "get_1284_register timeout\n");
241 	kill_all_async_requests_priv(priv);
242 	return -EIO;
243 }
244 
245 static int set_1284_register(struct parport *pp, unsigned char reg, unsigned char val, gfp_t mem_flags)
246 {
247 	struct parport_uss720_private *priv;
248 	struct uss720_async_request *rq;
249 
250 	if (!pp)
251 		return -EIO;
252 	priv = pp->private_data;
253 	rq = submit_async_request(priv, 4, 0x40, (((unsigned int)reg) << 8) | val, 0, mem_flags);
254 	if (!rq) {
255 		dev_err(&priv->usbdev->dev, "set_1284_register(%u,%u) failed",
256 			(unsigned int)reg, (unsigned int)val);
257 		return -EIO;
258 	}
259 	kref_put(&rq->ref_count, destroy_async);
260 	return 0;
261 }
262 
263 /* --------------------------------------------------------------------- */
264 
265 /* ECR modes */
266 #define ECR_SPP 00
267 #define ECR_PS2 01
268 #define ECR_PPF 02
269 #define ECR_ECP 03
270 #define ECR_EPP 04
271 
272 /* Safely change the mode bits in the ECR */
273 static int change_mode(struct parport *pp, int m)
274 {
275 	struct parport_uss720_private *priv = pp->private_data;
276 	int mode;
277 	__u8 reg;
278 
279 	if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
280 		return -EIO;
281 	/* Bits <7:5> contain the mode. */
282 	mode = (priv->reg[2] >> 5) & 0x7;
283 	if (mode == m)
284 		return 0;
285 	/* We have to go through mode 000 or 001 */
286 	if (mode > ECR_PS2 && m > ECR_PS2)
287 		if (change_mode(pp, ECR_PS2))
288 			return -EIO;
289 
290 	if (m <= ECR_PS2 && !(priv->reg[1] & 0x20)) {
291 		/* This mode resets the FIFO, so we may
292 		 * have to wait for it to drain first. */
293 		unsigned long expire = jiffies + pp->physport->cad->timeout;
294 		switch (mode) {
295 		case ECR_PPF: /* Parallel Port FIFO mode */
296 		case ECR_ECP: /* ECP Parallel Port mode */
297 			/* Poll slowly. */
298 			for (;;) {
299 				if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
300 					return -EIO;
301 				if (priv->reg[2] & 0x01)
302 					break;
303 				if (time_after_eq (jiffies, expire))
304 					/* The FIFO is stuck. */
305 					return -EBUSY;
306 				msleep_interruptible(10);
307 				if (signal_pending (current))
308 					break;
309 			}
310 		}
311 	}
312 	/* Set the mode. */
313 	if (set_1284_register(pp, 6, m << 5, GFP_KERNEL))
314 		return -EIO;
315 	if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
316 		return -EIO;
317 	return 0;
318 }
319 
320 /*
321  * Clear TIMEOUT BIT in EPP MODE
322  */
323 static int clear_epp_timeout(struct parport *pp)
324 {
325 	unsigned char stat;
326 
327 	if (get_1284_register(pp, 1, &stat, GFP_KERNEL))
328 		return 1;
329 	return stat & 1;
330 }
331 
332 /*
333  * Access functions.
334  */
335 #if 0
336 static int uss720_irq(int usbstatus, void *buffer, int len, void *dev_id)
337 {
338 	struct parport *pp = (struct parport *)dev_id;
339 	struct parport_uss720_private *priv = pp->private_data;
340 
341 	if (usbstatus != 0 || len < 4 || !buffer)
342 		return 1;
343 	memcpy(priv->reg, buffer, 4);
344 	/* if nAck interrupts are enabled and we have an interrupt, call the interrupt procedure */
345 	if (priv->reg[2] & priv->reg[1] & 0x10)
346 		parport_generic_irq(pp);
347 	return 1;
348 }
349 #endif
350 
351 static void parport_uss720_write_data(struct parport *pp, unsigned char d)
352 {
353 	set_1284_register(pp, 0, d, GFP_KERNEL);
354 }
355 
356 static unsigned char parport_uss720_read_data(struct parport *pp)
357 {
358 	unsigned char ret;
359 
360 	if (get_1284_register(pp, 0, &ret, GFP_KERNEL))
361 		return 0;
362 	return ret;
363 }
364 
365 static void parport_uss720_write_control(struct parport *pp, unsigned char d)
366 {
367 	struct parport_uss720_private *priv = pp->private_data;
368 
369 	d = (d & 0xf) | (priv->reg[1] & 0xf0);
370 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
371 		return;
372 	priv->reg[1] = d;
373 }
374 
375 static unsigned char parport_uss720_read_control(struct parport *pp)
376 {
377 	struct parport_uss720_private *priv = pp->private_data;
378 	return priv->reg[1] & 0xf; /* Use soft copy */
379 }
380 
381 static unsigned char parport_uss720_frob_control(struct parport *pp, unsigned char mask, unsigned char val)
382 {
383 	struct parport_uss720_private *priv = pp->private_data;
384 	unsigned char d;
385 
386 	mask &= 0x0f;
387 	val &= 0x0f;
388 	d = (priv->reg[1] & (~mask)) ^ val;
389 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
390 		return 0;
391 	priv->reg[1] = d;
392 	return d & 0xf;
393 }
394 
395 static unsigned char parport_uss720_read_status(struct parport *pp)
396 {
397 	unsigned char ret;
398 
399 	if (get_1284_register(pp, 1, &ret, GFP_KERNEL))
400 		return 0;
401 	return ret & 0xf8;
402 }
403 
404 static void parport_uss720_disable_irq(struct parport *pp)
405 {
406 	struct parport_uss720_private *priv = pp->private_data;
407 	unsigned char d;
408 
409 	d = priv->reg[1] & ~0x10;
410 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
411 		return;
412 	priv->reg[1] = d;
413 }
414 
415 static void parport_uss720_enable_irq(struct parport *pp)
416 {
417 	struct parport_uss720_private *priv = pp->private_data;
418 	unsigned char d;
419 
420 	d = priv->reg[1] | 0x10;
421 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
422 		return;
423 	priv->reg[1] = d;
424 }
425 
426 static void parport_uss720_data_forward (struct parport *pp)
427 {
428 	struct parport_uss720_private *priv = pp->private_data;
429 	unsigned char d;
430 
431 	d = priv->reg[1] & ~0x20;
432 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
433 		return;
434 	priv->reg[1] = d;
435 }
436 
437 static void parport_uss720_data_reverse (struct parport *pp)
438 {
439 	struct parport_uss720_private *priv = pp->private_data;
440 	unsigned char d;
441 
442 	d = priv->reg[1] | 0x20;
443 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
444 		return;
445 	priv->reg[1] = d;
446 }
447 
448 static void parport_uss720_init_state(struct pardevice *dev, struct parport_state *s)
449 {
450 	s->u.pc.ctr = 0xc | (dev->irq_func ? 0x10 : 0x0);
451 	s->u.pc.ecr = 0x24;
452 }
453 
454 static void parport_uss720_save_state(struct parport *pp, struct parport_state *s)
455 {
456 	struct parport_uss720_private *priv = pp->private_data;
457 
458 #if 0
459 	if (get_1284_register(pp, 2, NULL, GFP_ATOMIC))
460 		return;
461 #endif
462 	s->u.pc.ctr = priv->reg[1];
463 	s->u.pc.ecr = priv->reg[2];
464 }
465 
466 static void parport_uss720_restore_state(struct parport *pp, struct parport_state *s)
467 {
468 	struct parport_uss720_private *priv = pp->private_data;
469 
470 	set_1284_register(pp, 2, s->u.pc.ctr, GFP_ATOMIC);
471 	set_1284_register(pp, 6, s->u.pc.ecr, GFP_ATOMIC);
472 	get_1284_register(pp, 2, NULL, GFP_ATOMIC);
473 	priv->reg[1] = s->u.pc.ctr;
474 	priv->reg[2] = s->u.pc.ecr;
475 }
476 
477 static size_t parport_uss720_epp_read_data(struct parport *pp, void *buf, size_t length, int flags)
478 {
479 	struct parport_uss720_private *priv = pp->private_data;
480 	size_t got = 0;
481 
482 	if (change_mode(pp, ECR_EPP))
483 		return 0;
484 	for (; got < length; got++) {
485 		if (get_1284_register(pp, 4, (char *)buf, GFP_KERNEL))
486 			break;
487 		buf++;
488 		if (priv->reg[0] & 0x01) {
489 			clear_epp_timeout(pp);
490 			break;
491 		}
492 	}
493 	change_mode(pp, ECR_PS2);
494 	return got;
495 }
496 
497 static size_t parport_uss720_epp_write_data(struct parport *pp, const void *buf, size_t length, int flags)
498 {
499 #if 0
500 	struct parport_uss720_private *priv = pp->private_data;
501 	size_t written = 0;
502 
503 	if (change_mode(pp, ECR_EPP))
504 		return 0;
505 	for (; written < length; written++) {
506 		if (set_1284_register(pp, 4, (char *)buf, GFP_KERNEL))
507 			break;
508 		((char*)buf)++;
509 		if (get_1284_register(pp, 1, NULL, GFP_KERNEL))
510 			break;
511 		if (priv->reg[0] & 0x01) {
512 			clear_epp_timeout(pp);
513 			break;
514 		}
515 	}
516 	change_mode(pp, ECR_PS2);
517 	return written;
518 #else
519 	struct parport_uss720_private *priv = pp->private_data;
520 	struct usb_device *usbdev = priv->usbdev;
521 	int rlen;
522 	int i;
523 
524 	if (!usbdev)
525 		return 0;
526 	if (change_mode(pp, ECR_EPP))
527 		return 0;
528 	i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buf, length, &rlen, 20000);
529 	if (i)
530 		printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %zu rlen %u\n", buf, length, rlen);
531 	change_mode(pp, ECR_PS2);
532 	return rlen;
533 #endif
534 }
535 
536 static size_t parport_uss720_epp_read_addr(struct parport *pp, void *buf, size_t length, int flags)
537 {
538 	struct parport_uss720_private *priv = pp->private_data;
539 	size_t got = 0;
540 
541 	if (change_mode(pp, ECR_EPP))
542 		return 0;
543 	for (; got < length; got++) {
544 		if (get_1284_register(pp, 3, (char *)buf, GFP_KERNEL))
545 			break;
546 		buf++;
547 		if (priv->reg[0] & 0x01) {
548 			clear_epp_timeout(pp);
549 			break;
550 		}
551 	}
552 	change_mode(pp, ECR_PS2);
553 	return got;
554 }
555 
556 static size_t parport_uss720_epp_write_addr(struct parport *pp, const void *buf, size_t length, int flags)
557 {
558 	struct parport_uss720_private *priv = pp->private_data;
559 	size_t written = 0;
560 
561 	if (change_mode(pp, ECR_EPP))
562 		return 0;
563 	for (; written < length; written++) {
564 		if (set_1284_register(pp, 3, *(char *)buf, GFP_KERNEL))
565 			break;
566 		buf++;
567 		if (get_1284_register(pp, 1, NULL, GFP_KERNEL))
568 			break;
569 		if (priv->reg[0] & 0x01) {
570 			clear_epp_timeout(pp);
571 			break;
572 		}
573 	}
574 	change_mode(pp, ECR_PS2);
575 	return written;
576 }
577 
578 static size_t parport_uss720_ecp_write_data(struct parport *pp, const void *buffer, size_t len, int flags)
579 {
580 	struct parport_uss720_private *priv = pp->private_data;
581 	struct usb_device *usbdev = priv->usbdev;
582 	int rlen;
583 	int i;
584 
585 	if (!usbdev)
586 		return 0;
587 	if (change_mode(pp, ECR_ECP))
588 		return 0;
589 	i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buffer, len, &rlen, 20000);
590 	if (i)
591 		printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %zu rlen %u\n", buffer, len, rlen);
592 	change_mode(pp, ECR_PS2);
593 	return rlen;
594 }
595 
596 static size_t parport_uss720_ecp_read_data(struct parport *pp, void *buffer, size_t len, int flags)
597 {
598 	struct parport_uss720_private *priv = pp->private_data;
599 	struct usb_device *usbdev = priv->usbdev;
600 	int rlen;
601 	int i;
602 
603 	if (!usbdev)
604 		return 0;
605 	if (change_mode(pp, ECR_ECP))
606 		return 0;
607 	i = usb_bulk_msg(usbdev, usb_rcvbulkpipe(usbdev, 2), buffer, len, &rlen, 20000);
608 	if (i)
609 		printk(KERN_ERR "uss720: recvbulk ep 2 buf %p len %zu rlen %u\n", buffer, len, rlen);
610 	change_mode(pp, ECR_PS2);
611 	return rlen;
612 }
613 
614 static size_t parport_uss720_ecp_write_addr(struct parport *pp, const void *buffer, size_t len, int flags)
615 {
616 	size_t written = 0;
617 
618 	if (change_mode(pp, ECR_ECP))
619 		return 0;
620 	for (; written < len; written++) {
621 		if (set_1284_register(pp, 5, *(char *)buffer, GFP_KERNEL))
622 			break;
623 		buffer++;
624 	}
625 	change_mode(pp, ECR_PS2);
626 	return written;
627 }
628 
629 static size_t parport_uss720_write_compat(struct parport *pp, const void *buffer, size_t len, int flags)
630 {
631 	struct parport_uss720_private *priv = pp->private_data;
632 	struct usb_device *usbdev = priv->usbdev;
633 	int rlen;
634 	int i;
635 
636 	if (!usbdev)
637 		return 0;
638 	if (change_mode(pp, ECR_PPF))
639 		return 0;
640 	i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buffer, len, &rlen, 20000);
641 	if (i)
642 		printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %zu rlen %u\n", buffer, len, rlen);
643 	change_mode(pp, ECR_PS2);
644 	return rlen;
645 }
646 
647 /* --------------------------------------------------------------------- */
648 
649 static struct parport_operations parport_uss720_ops =
650 {
651 	.owner =		THIS_MODULE,
652 	.write_data =		parport_uss720_write_data,
653 	.read_data =		parport_uss720_read_data,
654 
655 	.write_control =	parport_uss720_write_control,
656 	.read_control =		parport_uss720_read_control,
657 	.frob_control =		parport_uss720_frob_control,
658 
659 	.read_status =		parport_uss720_read_status,
660 
661 	.enable_irq =		parport_uss720_enable_irq,
662 	.disable_irq =		parport_uss720_disable_irq,
663 
664 	.data_forward =		parport_uss720_data_forward,
665 	.data_reverse =		parport_uss720_data_reverse,
666 
667 	.init_state =		parport_uss720_init_state,
668 	.save_state =		parport_uss720_save_state,
669 	.restore_state =	parport_uss720_restore_state,
670 
671 	.epp_write_data =	parport_uss720_epp_write_data,
672 	.epp_read_data =	parport_uss720_epp_read_data,
673 	.epp_write_addr =	parport_uss720_epp_write_addr,
674 	.epp_read_addr =	parport_uss720_epp_read_addr,
675 
676 	.ecp_write_data =	parport_uss720_ecp_write_data,
677 	.ecp_read_data =	parport_uss720_ecp_read_data,
678 	.ecp_write_addr =	parport_uss720_ecp_write_addr,
679 
680 	.compat_write_data =	parport_uss720_write_compat,
681 	.nibble_read_data =	parport_ieee1284_read_nibble,
682 	.byte_read_data =	parport_ieee1284_read_byte,
683 };
684 
685 /* --------------------------------------------------------------------- */
686 
687 static int uss720_probe(struct usb_interface *intf,
688 			const struct usb_device_id *id)
689 {
690 	struct usb_device *usbdev = usb_get_dev(interface_to_usbdev(intf));
691 	struct usb_host_interface *interface;
692 	struct usb_endpoint_descriptor *epd;
693 	struct parport_uss720_private *priv;
694 	struct parport *pp;
695 	unsigned char reg;
696 	int i;
697 
698 	dev_dbg(&intf->dev, "probe: vendor id 0x%x, device id 0x%x\n",
699 		le16_to_cpu(usbdev->descriptor.idVendor),
700 		le16_to_cpu(usbdev->descriptor.idProduct));
701 
702 	/* our known interfaces have 3 alternate settings */
703 	if (intf->num_altsetting != 3) {
704 		usb_put_dev(usbdev);
705 		return -ENODEV;
706 	}
707 	i = usb_set_interface(usbdev, intf->altsetting->desc.bInterfaceNumber, 2);
708 	dev_dbg(&intf->dev, "set interface result %d\n", i);
709 
710 	interface = intf->cur_altsetting;
711 
712 	if (interface->desc.bNumEndpoints < 3) {
713 		usb_put_dev(usbdev);
714 		return -ENODEV;
715 	}
716 
717 	/*
718 	 * Allocate parport interface
719 	 */
720 	priv = kzalloc(sizeof(struct parport_uss720_private), GFP_KERNEL);
721 	if (!priv) {
722 		usb_put_dev(usbdev);
723 		return -ENOMEM;
724 	}
725 	priv->pp = NULL;
726 	priv->usbdev = usbdev;
727 	kref_init(&priv->ref_count);
728 	spin_lock_init(&priv->asynclock);
729 	INIT_LIST_HEAD(&priv->asynclist);
730 	pp = parport_register_port(0, PARPORT_IRQ_NONE, PARPORT_DMA_NONE, &parport_uss720_ops);
731 	if (!pp) {
732 		printk(KERN_WARNING "uss720: could not register parport\n");
733 		goto probe_abort;
734 	}
735 
736 	priv->pp = pp;
737 	pp->private_data = priv;
738 	pp->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_TRISTATE | PARPORT_MODE_EPP | PARPORT_MODE_ECP | PARPORT_MODE_COMPAT;
739 
740 	/* set the USS720 control register to manual mode, no ECP compression, enable all ints */
741 	set_1284_register(pp, 7, 0x00, GFP_KERNEL);
742 	set_1284_register(pp, 6, 0x30, GFP_KERNEL);  /* PS/2 mode */
743 	set_1284_register(pp, 2, 0x0c, GFP_KERNEL);
744 	/* debugging */
745 	get_1284_register(pp, 0, &reg, GFP_KERNEL);
746 	dev_dbg(&intf->dev, "reg: %7ph\n", priv->reg);
747 
748 	i = usb_find_last_int_in_endpoint(interface, &epd);
749 	if (!i) {
750 		dev_dbg(&intf->dev, "epaddr %d interval %d\n",
751 				epd->bEndpointAddress, epd->bInterval);
752 	}
753 	parport_announce_port(pp);
754 
755 	usb_set_intfdata(intf, pp);
756 	return 0;
757 
758 probe_abort:
759 	kill_all_async_requests_priv(priv);
760 	kref_put(&priv->ref_count, destroy_priv);
761 	return -ENODEV;
762 }
763 
764 static void uss720_disconnect(struct usb_interface *intf)
765 {
766 	struct parport *pp = usb_get_intfdata(intf);
767 	struct parport_uss720_private *priv;
768 	struct usb_device *usbdev;
769 
770 	dev_dbg(&intf->dev, "disconnect\n");
771 	usb_set_intfdata(intf, NULL);
772 	if (pp) {
773 		priv = pp->private_data;
774 		usbdev = priv->usbdev;
775 		priv->usbdev = NULL;
776 		priv->pp = NULL;
777 		dev_dbg(&intf->dev, "parport_remove_port\n");
778 		parport_remove_port(pp);
779 		parport_put_port(pp);
780 		kill_all_async_requests_priv(priv);
781 		kref_put(&priv->ref_count, destroy_priv);
782 	}
783 	dev_dbg(&intf->dev, "disconnect done\n");
784 }
785 
786 /* table of cables that work through this driver */
787 static const struct usb_device_id uss720_table[] = {
788 	{ USB_DEVICE(0x047e, 0x1001) },
789 	{ USB_DEVICE(0x0557, 0x2001) },
790 	{ USB_DEVICE(0x0729, 0x1284) },
791 	{ USB_DEVICE(0x1293, 0x0002) },
792 	{ USB_DEVICE(0x050d, 0x0002) },
793 	{ }						/* Terminating entry */
794 };
795 
796 MODULE_DEVICE_TABLE (usb, uss720_table);
797 
798 
799 static struct usb_driver uss720_driver = {
800 	.name =		"uss720",
801 	.probe =	uss720_probe,
802 	.disconnect =	uss720_disconnect,
803 	.id_table =	uss720_table,
804 };
805 
806 /* --------------------------------------------------------------------- */
807 
808 MODULE_AUTHOR(DRIVER_AUTHOR);
809 MODULE_DESCRIPTION(DRIVER_DESC);
810 MODULE_LICENSE("GPL");
811 
812 static int __init uss720_init(void)
813 {
814 	int retval;
815 	retval = usb_register(&uss720_driver);
816 	if (retval)
817 		goto out;
818 
819 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
820 	       DRIVER_DESC "\n");
821 	printk(KERN_INFO KBUILD_MODNAME ": NOTE: this is a special purpose "
822 	       "driver to allow nonstandard\n");
823 	printk(KERN_INFO KBUILD_MODNAME ": protocols (eg. bitbang) over "
824 	       "USS720 usb to parallel cables\n");
825 	printk(KERN_INFO KBUILD_MODNAME ": If you just want to connect to a "
826 	       "printer, use usblp instead\n");
827 out:
828 	return retval;
829 }
830 
831 static void __exit uss720_cleanup(void)
832 {
833 	usb_deregister(&uss720_driver);
834 }
835 
836 module_init(uss720_init);
837 module_exit(uss720_cleanup);
838 
839 /* --------------------------------------------------------------------- */
840