xref: /openbmc/linux/drivers/usb/misc/uss720.c (revision 0edbfea5)
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 		dev_err(&usbdev->dev, "submit_async_request out of memory\n");
155 		return NULL;
156 	}
157 	kref_init(&rq->ref_count);
158 	INIT_LIST_HEAD(&rq->asynclist);
159 	init_completion(&rq->compl);
160 	kref_get(&priv->ref_count);
161 	rq->priv = priv;
162 	rq->urb = usb_alloc_urb(0, mem_flags);
163 	if (!rq->urb) {
164 		kref_put(&rq->ref_count, destroy_async);
165 		dev_err(&usbdev->dev, "submit_async_request out of memory\n");
166 		return NULL;
167 	}
168 	rq->dr = kmalloc(sizeof(*rq->dr), mem_flags);
169 	if (!rq->dr) {
170 		kref_put(&rq->ref_count, destroy_async);
171 		return NULL;
172 	}
173 	rq->dr->bRequestType = requesttype;
174 	rq->dr->bRequest = request;
175 	rq->dr->wValue = cpu_to_le16(value);
176 	rq->dr->wIndex = cpu_to_le16(index);
177 	rq->dr->wLength = cpu_to_le16((request == 3) ? sizeof(rq->reg) : 0);
178 	usb_fill_control_urb(rq->urb, usbdev, (requesttype & 0x80) ? usb_rcvctrlpipe(usbdev, 0) : usb_sndctrlpipe(usbdev, 0),
179 			     (unsigned char *)rq->dr,
180 			     (request == 3) ? rq->reg : NULL, (request == 3) ? sizeof(rq->reg) : 0, async_complete, rq);
181 	/* rq->urb->transfer_flags |= URB_ASYNC_UNLINK; */
182 	spin_lock_irqsave(&priv->asynclock, flags);
183 	list_add_tail(&rq->asynclist, &priv->asynclist);
184 	spin_unlock_irqrestore(&priv->asynclock, flags);
185 	kref_get(&rq->ref_count);
186 	ret = usb_submit_urb(rq->urb, mem_flags);
187 	if (!ret)
188 		return rq;
189 	destroy_async(&rq->ref_count);
190 	dev_err(&usbdev->dev, "submit_async_request submit_urb failed with %d\n", ret);
191 	return NULL;
192 }
193 
194 static unsigned int kill_all_async_requests_priv(struct parport_uss720_private *priv)
195 {
196 	struct uss720_async_request *rq;
197 	unsigned long flags;
198 	unsigned int ret = 0;
199 
200 	spin_lock_irqsave(&priv->asynclock, flags);
201 	list_for_each_entry(rq, &priv->asynclist, asynclist) {
202 		usb_unlink_urb(rq->urb);
203 		ret++;
204 	}
205 	spin_unlock_irqrestore(&priv->asynclock, flags);
206 	return ret;
207 }
208 
209 /* --------------------------------------------------------------------- */
210 
211 static int get_1284_register(struct parport *pp, unsigned char reg, unsigned char *val, gfp_t mem_flags)
212 {
213 	struct parport_uss720_private *priv;
214 	struct uss720_async_request *rq;
215 	static const unsigned char regindex[9] = {
216 		4, 0, 1, 5, 5, 0, 2, 3, 6
217 	};
218 	int ret;
219 
220 	if (!pp)
221 		return -EIO;
222 	priv = pp->private_data;
223 	rq = submit_async_request(priv, 3, 0xc0, ((unsigned int)reg) << 8, 0, mem_flags);
224 	if (!rq) {
225 		dev_err(&priv->usbdev->dev, "get_1284_register(%u) failed",
226 			(unsigned int)reg);
227 		return -EIO;
228 	}
229 	if (!val) {
230 		kref_put(&rq->ref_count, destroy_async);
231 		return 0;
232 	}
233 	if (wait_for_completion_timeout(&rq->compl, HZ)) {
234 		ret = rq->urb->status;
235 		*val = priv->reg[(reg >= 9) ? 0 : regindex[reg]];
236 		if (ret)
237 			printk(KERN_WARNING "get_1284_register: "
238 			       "usb error %d\n", ret);
239 		kref_put(&rq->ref_count, destroy_async);
240 		return ret;
241 	}
242 	printk(KERN_WARNING "get_1284_register timeout\n");
243 	kill_all_async_requests_priv(priv);
244 	return -EIO;
245 }
246 
247 static int set_1284_register(struct parport *pp, unsigned char reg, unsigned char val, gfp_t mem_flags)
248 {
249 	struct parport_uss720_private *priv;
250 	struct uss720_async_request *rq;
251 
252 	if (!pp)
253 		return -EIO;
254 	priv = pp->private_data;
255 	rq = submit_async_request(priv, 4, 0x40, (((unsigned int)reg) << 8) | val, 0, mem_flags);
256 	if (!rq) {
257 		dev_err(&priv->usbdev->dev, "set_1284_register(%u,%u) failed",
258 			(unsigned int)reg, (unsigned int)val);
259 		return -EIO;
260 	}
261 	kref_put(&rq->ref_count, destroy_async);
262 	return 0;
263 }
264 
265 /* --------------------------------------------------------------------- */
266 
267 /* ECR modes */
268 #define ECR_SPP 00
269 #define ECR_PS2 01
270 #define ECR_PPF 02
271 #define ECR_ECP 03
272 #define ECR_EPP 04
273 
274 /* Safely change the mode bits in the ECR */
275 static int change_mode(struct parport *pp, int m)
276 {
277 	struct parport_uss720_private *priv = pp->private_data;
278 	int mode;
279 	__u8 reg;
280 
281 	if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
282 		return -EIO;
283 	/* Bits <7:5> contain the mode. */
284 	mode = (priv->reg[2] >> 5) & 0x7;
285 	if (mode == m)
286 		return 0;
287 	/* We have to go through mode 000 or 001 */
288 	if (mode > ECR_PS2 && m > ECR_PS2)
289 		if (change_mode(pp, ECR_PS2))
290 			return -EIO;
291 
292 	if (m <= ECR_PS2 && !(priv->reg[1] & 0x20)) {
293 		/* This mode resets the FIFO, so we may
294 		 * have to wait for it to drain first. */
295 		unsigned long expire = jiffies + pp->physport->cad->timeout;
296 		switch (mode) {
297 		case ECR_PPF: /* Parallel Port FIFO mode */
298 		case ECR_ECP: /* ECP Parallel Port mode */
299 			/* Poll slowly. */
300 			for (;;) {
301 				if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
302 					return -EIO;
303 				if (priv->reg[2] & 0x01)
304 					break;
305 				if (time_after_eq (jiffies, expire))
306 					/* The FIFO is stuck. */
307 					return -EBUSY;
308 				msleep_interruptible(10);
309 				if (signal_pending (current))
310 					break;
311 			}
312 		}
313 	}
314 	/* Set the mode. */
315 	if (set_1284_register(pp, 6, m << 5, GFP_KERNEL))
316 		return -EIO;
317 	if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
318 		return -EIO;
319 	return 0;
320 }
321 
322 /*
323  * Clear TIMEOUT BIT in EPP MODE
324  */
325 static int clear_epp_timeout(struct parport *pp)
326 {
327 	unsigned char stat;
328 
329 	if (get_1284_register(pp, 1, &stat, GFP_KERNEL))
330 		return 1;
331 	return stat & 1;
332 }
333 
334 /*
335  * Access functions.
336  */
337 #if 0
338 static int uss720_irq(int usbstatus, void *buffer, int len, void *dev_id)
339 {
340 	struct parport *pp = (struct parport *)dev_id;
341 	struct parport_uss720_private *priv = pp->private_data;
342 
343 	if (usbstatus != 0 || len < 4 || !buffer)
344 		return 1;
345 	memcpy(priv->reg, buffer, 4);
346 	/* if nAck interrupts are enabled and we have an interrupt, call the interrupt procedure */
347 	if (priv->reg[2] & priv->reg[1] & 0x10)
348 		parport_generic_irq(pp);
349 	return 1;
350 }
351 #endif
352 
353 static void parport_uss720_write_data(struct parport *pp, unsigned char d)
354 {
355 	set_1284_register(pp, 0, d, GFP_KERNEL);
356 }
357 
358 static unsigned char parport_uss720_read_data(struct parport *pp)
359 {
360 	unsigned char ret;
361 
362 	if (get_1284_register(pp, 0, &ret, GFP_KERNEL))
363 		return 0;
364 	return ret;
365 }
366 
367 static void parport_uss720_write_control(struct parport *pp, unsigned char d)
368 {
369 	struct parport_uss720_private *priv = pp->private_data;
370 
371 	d = (d & 0xf) | (priv->reg[1] & 0xf0);
372 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
373 		return;
374 	priv->reg[1] = d;
375 }
376 
377 static unsigned char parport_uss720_read_control(struct parport *pp)
378 {
379 	struct parport_uss720_private *priv = pp->private_data;
380 	return priv->reg[1] & 0xf; /* Use soft copy */
381 }
382 
383 static unsigned char parport_uss720_frob_control(struct parport *pp, unsigned char mask, unsigned char val)
384 {
385 	struct parport_uss720_private *priv = pp->private_data;
386 	unsigned char d;
387 
388 	mask &= 0x0f;
389 	val &= 0x0f;
390 	d = (priv->reg[1] & (~mask)) ^ val;
391 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
392 		return 0;
393 	priv->reg[1] = d;
394 	return d & 0xf;
395 }
396 
397 static unsigned char parport_uss720_read_status(struct parport *pp)
398 {
399 	unsigned char ret;
400 
401 	if (get_1284_register(pp, 1, &ret, GFP_KERNEL))
402 		return 0;
403 	return ret & 0xf8;
404 }
405 
406 static void parport_uss720_disable_irq(struct parport *pp)
407 {
408 	struct parport_uss720_private *priv = pp->private_data;
409 	unsigned char d;
410 
411 	d = priv->reg[1] & ~0x10;
412 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
413 		return;
414 	priv->reg[1] = d;
415 }
416 
417 static void parport_uss720_enable_irq(struct parport *pp)
418 {
419 	struct parport_uss720_private *priv = pp->private_data;
420 	unsigned char d;
421 
422 	d = priv->reg[1] | 0x10;
423 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
424 		return;
425 	priv->reg[1] = d;
426 }
427 
428 static void parport_uss720_data_forward (struct parport *pp)
429 {
430 	struct parport_uss720_private *priv = pp->private_data;
431 	unsigned char d;
432 
433 	d = priv->reg[1] & ~0x20;
434 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
435 		return;
436 	priv->reg[1] = d;
437 }
438 
439 static void parport_uss720_data_reverse (struct parport *pp)
440 {
441 	struct parport_uss720_private *priv = pp->private_data;
442 	unsigned char d;
443 
444 	d = priv->reg[1] | 0x20;
445 	if (set_1284_register(pp, 2, d, GFP_KERNEL))
446 		return;
447 	priv->reg[1] = d;
448 }
449 
450 static void parport_uss720_init_state(struct pardevice *dev, struct parport_state *s)
451 {
452 	s->u.pc.ctr = 0xc | (dev->irq_func ? 0x10 : 0x0);
453 	s->u.pc.ecr = 0x24;
454 }
455 
456 static void parport_uss720_save_state(struct parport *pp, struct parport_state *s)
457 {
458 	struct parport_uss720_private *priv = pp->private_data;
459 
460 #if 0
461 	if (get_1284_register(pp, 2, NULL, GFP_ATOMIC))
462 		return;
463 #endif
464 	s->u.pc.ctr = priv->reg[1];
465 	s->u.pc.ecr = priv->reg[2];
466 }
467 
468 static void parport_uss720_restore_state(struct parport *pp, struct parport_state *s)
469 {
470 	struct parport_uss720_private *priv = pp->private_data;
471 
472 	set_1284_register(pp, 2, s->u.pc.ctr, GFP_ATOMIC);
473 	set_1284_register(pp, 6, s->u.pc.ecr, GFP_ATOMIC);
474 	get_1284_register(pp, 2, NULL, GFP_ATOMIC);
475 	priv->reg[1] = s->u.pc.ctr;
476 	priv->reg[2] = s->u.pc.ecr;
477 }
478 
479 static size_t parport_uss720_epp_read_data(struct parport *pp, void *buf, size_t length, int flags)
480 {
481 	struct parport_uss720_private *priv = pp->private_data;
482 	size_t got = 0;
483 
484 	if (change_mode(pp, ECR_EPP))
485 		return 0;
486 	for (; got < length; got++) {
487 		if (get_1284_register(pp, 4, (char *)buf, GFP_KERNEL))
488 			break;
489 		buf++;
490 		if (priv->reg[0] & 0x01) {
491 			clear_epp_timeout(pp);
492 			break;
493 		}
494 	}
495 	change_mode(pp, ECR_PS2);
496 	return got;
497 }
498 
499 static size_t parport_uss720_epp_write_data(struct parport *pp, const void *buf, size_t length, int flags)
500 {
501 #if 0
502 	struct parport_uss720_private *priv = pp->private_data;
503 	size_t written = 0;
504 
505 	if (change_mode(pp, ECR_EPP))
506 		return 0;
507 	for (; written < length; written++) {
508 		if (set_1284_register(pp, 4, (char *)buf, GFP_KERNEL))
509 			break;
510 		((char*)buf)++;
511 		if (get_1284_register(pp, 1, NULL, GFP_KERNEL))
512 			break;
513 		if (priv->reg[0] & 0x01) {
514 			clear_epp_timeout(pp);
515 			break;
516 		}
517 	}
518 	change_mode(pp, ECR_PS2);
519 	return written;
520 #else
521 	struct parport_uss720_private *priv = pp->private_data;
522 	struct usb_device *usbdev = priv->usbdev;
523 	int rlen;
524 	int i;
525 
526 	if (!usbdev)
527 		return 0;
528 	if (change_mode(pp, ECR_EPP))
529 		return 0;
530 	i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buf, length, &rlen, 20000);
531 	if (i)
532 		printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %Zu rlen %u\n", buf, length, rlen);
533 	change_mode(pp, ECR_PS2);
534 	return rlen;
535 #endif
536 }
537 
538 static size_t parport_uss720_epp_read_addr(struct parport *pp, void *buf, size_t length, int flags)
539 {
540 	struct parport_uss720_private *priv = pp->private_data;
541 	size_t got = 0;
542 
543 	if (change_mode(pp, ECR_EPP))
544 		return 0;
545 	for (; got < length; got++) {
546 		if (get_1284_register(pp, 3, (char *)buf, GFP_KERNEL))
547 			break;
548 		buf++;
549 		if (priv->reg[0] & 0x01) {
550 			clear_epp_timeout(pp);
551 			break;
552 		}
553 	}
554 	change_mode(pp, ECR_PS2);
555 	return got;
556 }
557 
558 static size_t parport_uss720_epp_write_addr(struct parport *pp, const void *buf, size_t length, int flags)
559 {
560 	struct parport_uss720_private *priv = pp->private_data;
561 	size_t written = 0;
562 
563 	if (change_mode(pp, ECR_EPP))
564 		return 0;
565 	for (; written < length; written++) {
566 		if (set_1284_register(pp, 3, *(char *)buf, GFP_KERNEL))
567 			break;
568 		buf++;
569 		if (get_1284_register(pp, 1, NULL, GFP_KERNEL))
570 			break;
571 		if (priv->reg[0] & 0x01) {
572 			clear_epp_timeout(pp);
573 			break;
574 		}
575 	}
576 	change_mode(pp, ECR_PS2);
577 	return written;
578 }
579 
580 static size_t parport_uss720_ecp_write_data(struct parport *pp, const void *buffer, size_t len, int flags)
581 {
582 	struct parport_uss720_private *priv = pp->private_data;
583 	struct usb_device *usbdev = priv->usbdev;
584 	int rlen;
585 	int i;
586 
587 	if (!usbdev)
588 		return 0;
589 	if (change_mode(pp, ECR_ECP))
590 		return 0;
591 	i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buffer, len, &rlen, 20000);
592 	if (i)
593 		printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %Zu rlen %u\n", buffer, len, rlen);
594 	change_mode(pp, ECR_PS2);
595 	return rlen;
596 }
597 
598 static size_t parport_uss720_ecp_read_data(struct parport *pp, void *buffer, size_t len, int flags)
599 {
600 	struct parport_uss720_private *priv = pp->private_data;
601 	struct usb_device *usbdev = priv->usbdev;
602 	int rlen;
603 	int i;
604 
605 	if (!usbdev)
606 		return 0;
607 	if (change_mode(pp, ECR_ECP))
608 		return 0;
609 	i = usb_bulk_msg(usbdev, usb_rcvbulkpipe(usbdev, 2), buffer, len, &rlen, 20000);
610 	if (i)
611 		printk(KERN_ERR "uss720: recvbulk ep 2 buf %p len %Zu rlen %u\n", buffer, len, rlen);
612 	change_mode(pp, ECR_PS2);
613 	return rlen;
614 }
615 
616 static size_t parport_uss720_ecp_write_addr(struct parport *pp, const void *buffer, size_t len, int flags)
617 {
618 	size_t written = 0;
619 
620 	if (change_mode(pp, ECR_ECP))
621 		return 0;
622 	for (; written < len; written++) {
623 		if (set_1284_register(pp, 5, *(char *)buffer, GFP_KERNEL))
624 			break;
625 		buffer++;
626 	}
627 	change_mode(pp, ECR_PS2);
628 	return written;
629 }
630 
631 static size_t parport_uss720_write_compat(struct parport *pp, const void *buffer, size_t len, int flags)
632 {
633 	struct parport_uss720_private *priv = pp->private_data;
634 	struct usb_device *usbdev = priv->usbdev;
635 	int rlen;
636 	int i;
637 
638 	if (!usbdev)
639 		return 0;
640 	if (change_mode(pp, ECR_PPF))
641 		return 0;
642 	i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buffer, len, &rlen, 20000);
643 	if (i)
644 		printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %Zu rlen %u\n", buffer, len, rlen);
645 	change_mode(pp, ECR_PS2);
646 	return rlen;
647 }
648 
649 /* --------------------------------------------------------------------- */
650 
651 static struct parport_operations parport_uss720_ops =
652 {
653 	.owner =		THIS_MODULE,
654 	.write_data =		parport_uss720_write_data,
655 	.read_data =		parport_uss720_read_data,
656 
657 	.write_control =	parport_uss720_write_control,
658 	.read_control =		parport_uss720_read_control,
659 	.frob_control =		parport_uss720_frob_control,
660 
661 	.read_status =		parport_uss720_read_status,
662 
663 	.enable_irq =		parport_uss720_enable_irq,
664 	.disable_irq =		parport_uss720_disable_irq,
665 
666 	.data_forward =		parport_uss720_data_forward,
667 	.data_reverse =		parport_uss720_data_reverse,
668 
669 	.init_state =		parport_uss720_init_state,
670 	.save_state =		parport_uss720_save_state,
671 	.restore_state =	parport_uss720_restore_state,
672 
673 	.epp_write_data =	parport_uss720_epp_write_data,
674 	.epp_read_data =	parport_uss720_epp_read_data,
675 	.epp_write_addr =	parport_uss720_epp_write_addr,
676 	.epp_read_addr =	parport_uss720_epp_read_addr,
677 
678 	.ecp_write_data =	parport_uss720_ecp_write_data,
679 	.ecp_read_data =	parport_uss720_ecp_read_data,
680 	.ecp_write_addr =	parport_uss720_ecp_write_addr,
681 
682 	.compat_write_data =	parport_uss720_write_compat,
683 	.nibble_read_data =	parport_ieee1284_read_nibble,
684 	.byte_read_data =	parport_ieee1284_read_byte,
685 };
686 
687 /* --------------------------------------------------------------------- */
688 
689 static int uss720_probe(struct usb_interface *intf,
690 			const struct usb_device_id *id)
691 {
692 	struct usb_device *usbdev = usb_get_dev(interface_to_usbdev(intf));
693 	struct usb_host_interface *interface;
694 	struct usb_host_endpoint *endpoint;
695 	struct parport_uss720_private *priv;
696 	struct parport *pp;
697 	unsigned char reg;
698 	int i;
699 
700 	dev_dbg(&intf->dev, "probe: vendor id 0x%x, device id 0x%x\n",
701 		le16_to_cpu(usbdev->descriptor.idVendor),
702 		le16_to_cpu(usbdev->descriptor.idProduct));
703 
704 	/* our known interfaces have 3 alternate settings */
705 	if (intf->num_altsetting != 3) {
706 		usb_put_dev(usbdev);
707 		return -ENODEV;
708 	}
709 	i = usb_set_interface(usbdev, intf->altsetting->desc.bInterfaceNumber, 2);
710 	dev_dbg(&intf->dev, "set interface result %d\n", i);
711 
712 	interface = intf->cur_altsetting;
713 
714 	/*
715 	 * Allocate parport interface
716 	 */
717 	priv = kzalloc(sizeof(struct parport_uss720_private), GFP_KERNEL);
718 	if (!priv) {
719 		usb_put_dev(usbdev);
720 		return -ENOMEM;
721 	}
722 	priv->pp = NULL;
723 	priv->usbdev = usbdev;
724 	kref_init(&priv->ref_count);
725 	spin_lock_init(&priv->asynclock);
726 	INIT_LIST_HEAD(&priv->asynclist);
727 	pp = parport_register_port(0, PARPORT_IRQ_NONE, PARPORT_DMA_NONE, &parport_uss720_ops);
728 	if (!pp) {
729 		printk(KERN_WARNING "uss720: could not register parport\n");
730 		goto probe_abort;
731 	}
732 
733 	priv->pp = pp;
734 	pp->private_data = priv;
735 	pp->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_TRISTATE | PARPORT_MODE_EPP | PARPORT_MODE_ECP | PARPORT_MODE_COMPAT;
736 
737 	/* set the USS720 control register to manual mode, no ECP compression, enable all ints */
738 	set_1284_register(pp, 7, 0x00, GFP_KERNEL);
739 	set_1284_register(pp, 6, 0x30, GFP_KERNEL);  /* PS/2 mode */
740 	set_1284_register(pp, 2, 0x0c, GFP_KERNEL);
741 	/* debugging */
742 	get_1284_register(pp, 0, &reg, GFP_KERNEL);
743 	dev_dbg(&intf->dev, "reg: %7ph\n", priv->reg);
744 
745 	endpoint = &interface->endpoint[2];
746 	dev_dbg(&intf->dev, "epaddr %d interval %d\n",
747 		endpoint->desc.bEndpointAddress, endpoint->desc.bInterval);
748 	parport_announce_port(pp);
749 
750 	usb_set_intfdata(intf, pp);
751 	return 0;
752 
753 probe_abort:
754 	kill_all_async_requests_priv(priv);
755 	kref_put(&priv->ref_count, destroy_priv);
756 	return -ENODEV;
757 }
758 
759 static void uss720_disconnect(struct usb_interface *intf)
760 {
761 	struct parport *pp = usb_get_intfdata(intf);
762 	struct parport_uss720_private *priv;
763 	struct usb_device *usbdev;
764 
765 	dev_dbg(&intf->dev, "disconnect\n");
766 	usb_set_intfdata(intf, NULL);
767 	if (pp) {
768 		priv = pp->private_data;
769 		usbdev = priv->usbdev;
770 		priv->usbdev = NULL;
771 		priv->pp = NULL;
772 		dev_dbg(&intf->dev, "parport_remove_port\n");
773 		parport_remove_port(pp);
774 		parport_put_port(pp);
775 		kill_all_async_requests_priv(priv);
776 		kref_put(&priv->ref_count, destroy_priv);
777 	}
778 	dev_dbg(&intf->dev, "disconnect done\n");
779 }
780 
781 /* table of cables that work through this driver */
782 static const struct usb_device_id uss720_table[] = {
783 	{ USB_DEVICE(0x047e, 0x1001) },
784 	{ USB_DEVICE(0x0557, 0x2001) },
785 	{ USB_DEVICE(0x0729, 0x1284) },
786 	{ USB_DEVICE(0x1293, 0x0002) },
787 	{ USB_DEVICE(0x050d, 0x0002) },
788 	{ }						/* Terminating entry */
789 };
790 
791 MODULE_DEVICE_TABLE (usb, uss720_table);
792 
793 
794 static struct usb_driver uss720_driver = {
795 	.name =		"uss720",
796 	.probe =	uss720_probe,
797 	.disconnect =	uss720_disconnect,
798 	.id_table =	uss720_table,
799 };
800 
801 /* --------------------------------------------------------------------- */
802 
803 MODULE_AUTHOR(DRIVER_AUTHOR);
804 MODULE_DESCRIPTION(DRIVER_DESC);
805 MODULE_LICENSE("GPL");
806 
807 static int __init uss720_init(void)
808 {
809 	int retval;
810 	retval = usb_register(&uss720_driver);
811 	if (retval)
812 		goto out;
813 
814 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
815 	       DRIVER_DESC "\n");
816 	printk(KERN_INFO KBUILD_MODNAME ": NOTE: this is a special purpose "
817 	       "driver to allow nonstandard\n");
818 	printk(KERN_INFO KBUILD_MODNAME ": protocols (eg. bitbang) over "
819 	       "USS720 usb to parallel cables\n");
820 	printk(KERN_INFO KBUILD_MODNAME ": If you just want to connect to a "
821 	       "printer, use usblp instead\n");
822 out:
823 	return retval;
824 }
825 
826 static void __exit uss720_cleanup(void)
827 {
828 	usb_deregister(&uss720_driver);
829 }
830 
831 module_init(uss720_init);
832 module_exit(uss720_cleanup);
833 
834 /* --------------------------------------------------------------------- */
835