1// SPDX-License-Identifier: GPL-2.0+
2/*****************************************************************************/
3
4/*
5 *	uss720.c  --  USS720 USB Parport Cable.
6 *
7 *	Copyright (C) 1999, 2005, 2010
8 *	    Thomas Sailer (t.sailer@alumni.ethz.ch)
9 *
10 *  Based on parport_pc.c
11 *
12 *  History:
13 *   0.1  04.08.1999  Created
14 *   0.2  07.08.1999  Some fixes mainly suggested by Tim Waugh
15 *		      Interrupt handling currently disabled because
16 *		      usb_request_irq crashes somewhere within ohci.c
17 *		      for no apparent reason (that is for me, anyway)
18 *		      ECP currently untested
19 *   0.3  10.08.1999  fixing merge errors
20 *   0.4  13.08.1999  Added Vendor/Product ID of Brad Hard's cable
21 *   0.5  20.09.1999  usb_control_msg wrapper used
22 *        Nov01.2000  usb_device_table support by Adam J. Richter
23 *        08.04.2001  Identify version on module load.  gb
24 *   0.6  02.09.2005  Fix "scheduling in interrupt" problem by making save/restore
25 *                    context asynchronous
26 *
27 */
28
29/*****************************************************************************/
30
31#include <linux/module.h>
32#include <linux/socket.h>
33#include <linux/parport.h>
34#include <linux/init.h>
35#include <linux/usb.h>
36#include <linux/delay.h>
37#include <linux/completion.h>
38#include <linux/kref.h>
39#include <linux/slab.h>
40#include <linux/sched/signal.h>
41
42#define DRIVER_AUTHOR "Thomas M. Sailer, t.sailer@alumni.ethz.ch"
43#define DRIVER_DESC "USB Parport Cable driver for Cables using the Lucent Technologies USS720 Chip"
44
45/* --------------------------------------------------------------------- */
46
47struct parport_uss720_private {
48	struct usb_device *usbdev;
49	struct parport *pp;
50	struct kref ref_count;
51	__u8 reg[7];  /* USB registers */
52	struct list_head asynclist;
53	spinlock_t asynclock;
54};
55
56struct uss720_async_request {
57	struct parport_uss720_private *priv;
58	struct kref ref_count;
59	struct list_head asynclist;
60	struct completion compl;
61	struct urb *urb;
62	struct usb_ctrlrequest *dr;
63	__u8 reg[7];
64};
65
66/* --------------------------------------------------------------------- */
67
68static void destroy_priv(struct kref *kref)
69{
70	struct parport_uss720_private *priv = container_of(kref, struct parport_uss720_private, ref_count);
71
72	dev_dbg(&priv->usbdev->dev, "destroying priv datastructure\n");
73	usb_put_dev(priv->usbdev);
74	priv->usbdev = NULL;
75	kfree(priv);
76}
77
78static void destroy_async(struct kref *kref)
79{
80	struct uss720_async_request *rq = container_of(kref, struct uss720_async_request, ref_count);
81	struct parport_uss720_private *priv = rq->priv;
82	unsigned long flags;
83
84	if (likely(rq->urb))
85		usb_free_urb(rq->urb);
86	kfree(rq->dr);
87	spin_lock_irqsave(&priv->asynclock, flags);
88	list_del_init(&rq->asynclist);
89	spin_unlock_irqrestore(&priv->asynclock, flags);
90	kfree(rq);
91	kref_put(&priv->ref_count, destroy_priv);
92}
93
94/* --------------------------------------------------------------------- */
95
96static void async_complete(struct urb *urb)
97{
98	struct uss720_async_request *rq;
99	struct parport *pp;
100	struct parport_uss720_private *priv;
101	int status = urb->status;
102
103	rq = urb->context;
104	priv = rq->priv;
105	pp = priv->pp;
106	if (status) {
107		dev_err(&urb->dev->dev, "async_complete: urb error %d\n",
108			status);
109	} else if (rq->dr->bRequest == 3) {
110		memcpy(priv->reg, rq->reg, sizeof(priv->reg));
111#if 0
112		dev_dbg(&priv->usbdev->dev, "async_complete regs %7ph\n",
113			priv->reg);
114#endif
115		/* if nAck interrupts are enabled and we have an interrupt, call the interrupt procedure */
116		if (rq->reg[2] & rq->reg[1] & 0x10 && pp)
117			parport_generic_irq(pp);
118	}
119	complete(&rq->compl);
120	kref_put(&rq->ref_count, destroy_async);
121}
122
123static struct uss720_async_request *submit_async_request(struct parport_uss720_private *priv,
124							 __u8 request, __u8 requesttype, __u16 value, __u16 index,
125							 gfp_t mem_flags)
126{
127	struct usb_device *usbdev;
128	struct uss720_async_request *rq;
129	unsigned long flags;
130	int ret;
131
132	if (!priv)
133		return NULL;
134	usbdev = priv->usbdev;
135	if (!usbdev)
136		return NULL;
137	rq = kzalloc(sizeof(struct uss720_async_request), mem_flags);
138	if (!rq)
139		return NULL;
140	kref_init(&rq->ref_count);
141	INIT_LIST_HEAD(&rq->asynclist);
142	init_completion(&rq->compl);
143	kref_get(&priv->ref_count);
144	rq->priv = priv;
145	rq->urb = usb_alloc_urb(0, mem_flags);
146	if (!rq->urb) {
147		kref_put(&rq->ref_count, destroy_async);
148		return NULL;
149	}
150	rq->dr = kmalloc(sizeof(*rq->dr), mem_flags);
151	if (!rq->dr) {
152		kref_put(&rq->ref_count, destroy_async);
153		return NULL;
154	}
155	rq->dr->bRequestType = requesttype;
156	rq->dr->bRequest = request;
157	rq->dr->wValue = cpu_to_le16(value);
158	rq->dr->wIndex = cpu_to_le16(index);
159	rq->dr->wLength = cpu_to_le16((request == 3) ? sizeof(rq->reg) : 0);
160	usb_fill_control_urb(rq->urb, usbdev, (requesttype & 0x80) ? usb_rcvctrlpipe(usbdev, 0) : usb_sndctrlpipe(usbdev, 0),
161			     (unsigned char *)rq->dr,
162			     (request == 3) ? rq->reg : NULL, (request == 3) ? sizeof(rq->reg) : 0, async_complete, rq);
163	/* rq->urb->transfer_flags |= URB_ASYNC_UNLINK; */
164	spin_lock_irqsave(&priv->asynclock, flags);
165	list_add_tail(&rq->asynclist, &priv->asynclist);
166	spin_unlock_irqrestore(&priv->asynclock, flags);
167	kref_get(&rq->ref_count);
168	ret = usb_submit_urb(rq->urb, mem_flags);
169	if (!ret)
170		return rq;
171	destroy_async(&rq->ref_count);
172	dev_err(&usbdev->dev, "submit_async_request submit_urb failed with %d\n", ret);
173	return NULL;
174}
175
176static unsigned int kill_all_async_requests_priv(struct parport_uss720_private *priv)
177{
178	struct uss720_async_request *rq;
179	unsigned long flags;
180	unsigned int ret = 0;
181
182	spin_lock_irqsave(&priv->asynclock, flags);
183	list_for_each_entry(rq, &priv->asynclist, asynclist) {
184		usb_unlink_urb(rq->urb);
185		ret++;
186	}
187	spin_unlock_irqrestore(&priv->asynclock, flags);
188	return ret;
189}
190
191/* --------------------------------------------------------------------- */
192
193static int get_1284_register(struct parport *pp, unsigned char reg, unsigned char *val, gfp_t mem_flags)
194{
195	struct parport_uss720_private *priv;
196	struct uss720_async_request *rq;
197	static const unsigned char regindex[9] = {
198		4, 0, 1, 5, 5, 0, 2, 3, 6
199	};
200	int ret;
201
202	if (!pp)
203		return -EIO;
204	priv = pp->private_data;
205	rq = submit_async_request(priv, 3, 0xc0, ((unsigned int)reg) << 8, 0, mem_flags);
206	if (!rq) {
207		dev_err(&priv->usbdev->dev, "get_1284_register(%u) failed",
208			(unsigned int)reg);
209		return -EIO;
210	}
211	if (!val) {
212		kref_put(&rq->ref_count, destroy_async);
213		return 0;
214	}
215	if (wait_for_completion_timeout(&rq->compl, HZ)) {
216		ret = rq->urb->status;
217		*val = priv->reg[(reg >= 9) ? 0 : regindex[reg]];
218		if (ret)
219			printk(KERN_WARNING "get_1284_register: "
220			       "usb error %d\n", ret);
221		kref_put(&rq->ref_count, destroy_async);
222		return ret;
223	}
224	printk(KERN_WARNING "get_1284_register timeout\n");
225	kill_all_async_requests_priv(priv);
226	return -EIO;
227}
228
229static int set_1284_register(struct parport *pp, unsigned char reg, unsigned char val, gfp_t mem_flags)
230{
231	struct parport_uss720_private *priv;
232	struct uss720_async_request *rq;
233
234	if (!pp)
235		return -EIO;
236	priv = pp->private_data;
237	rq = submit_async_request(priv, 4, 0x40, (((unsigned int)reg) << 8) | val, 0, mem_flags);
238	if (!rq) {
239		dev_err(&priv->usbdev->dev, "set_1284_register(%u,%u) failed",
240			(unsigned int)reg, (unsigned int)val);
241		return -EIO;
242	}
243	kref_put(&rq->ref_count, destroy_async);
244	return 0;
245}
246
247/* --------------------------------------------------------------------- */
248
249/* ECR modes */
250#define ECR_SPP 00
251#define ECR_PS2 01
252#define ECR_PPF 02
253#define ECR_ECP 03
254#define ECR_EPP 04
255
256/* Safely change the mode bits in the ECR */
257static int change_mode(struct parport *pp, int m)
258{
259	struct parport_uss720_private *priv = pp->private_data;
260	int mode;
261	__u8 reg;
262
263	if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
264		return -EIO;
265	/* Bits <7:5> contain the mode. */
266	mode = (priv->reg[2] >> 5) & 0x7;
267	if (mode == m)
268		return 0;
269	/* We have to go through mode 000 or 001 */
270	if (mode > ECR_PS2 && m > ECR_PS2)
271		if (change_mode(pp, ECR_PS2))
272			return -EIO;
273
274	if (m <= ECR_PS2 && !(priv->reg[1] & 0x20)) {
275		/* This mode resets the FIFO, so we may
276		 * have to wait for it to drain first. */
277		unsigned long expire = jiffies + pp->physport->cad->timeout;
278		switch (mode) {
279		case ECR_PPF: /* Parallel Port FIFO mode */
280		case ECR_ECP: /* ECP Parallel Port mode */
281			/* Poll slowly. */
282			for (;;) {
283				if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
284					return -EIO;
285				if (priv->reg[2] & 0x01)
286					break;
287				if (time_after_eq (jiffies, expire))
288					/* The FIFO is stuck. */
289					return -EBUSY;
290				msleep_interruptible(10);
291				if (signal_pending (current))
292					break;
293			}
294		}
295	}
296	/* Set the mode. */
297	if (set_1284_register(pp, 6, m << 5, GFP_KERNEL))
298		return -EIO;
299	if (get_1284_register(pp, 6, &reg, GFP_KERNEL))
300		return -EIO;
301	return 0;
302}
303
304/*
305 * Clear TIMEOUT BIT in EPP MODE
306 */
307static int clear_epp_timeout(struct parport *pp)
308{
309	unsigned char stat;
310
311	if (get_1284_register(pp, 1, &stat, GFP_KERNEL))
312		return 1;
313	return stat & 1;
314}
315
316/*
317 * Access functions.
318 */
319#if 0
320static int uss720_irq(int usbstatus, void *buffer, int len, void *dev_id)
321{
322	struct parport *pp = (struct parport *)dev_id;
323	struct parport_uss720_private *priv = pp->private_data;
324
325	if (usbstatus != 0 || len < 4 || !buffer)
326		return 1;
327	memcpy(priv->reg, buffer, 4);
328	/* if nAck interrupts are enabled and we have an interrupt, call the interrupt procedure */
329	if (priv->reg[2] & priv->reg[1] & 0x10)
330		parport_generic_irq(pp);
331	return 1;
332}
333#endif
334
335static void parport_uss720_write_data(struct parport *pp, unsigned char d)
336{
337	set_1284_register(pp, 0, d, GFP_KERNEL);
338}
339
340static unsigned char parport_uss720_read_data(struct parport *pp)
341{
342	unsigned char ret;
343
344	if (get_1284_register(pp, 0, &ret, GFP_KERNEL))
345		return 0;
346	return ret;
347}
348
349static void parport_uss720_write_control(struct parport *pp, unsigned char d)
350{
351	struct parport_uss720_private *priv = pp->private_data;
352
353	d = (d & 0xf) | (priv->reg[1] & 0xf0);
354	if (set_1284_register(pp, 2, d, GFP_KERNEL))
355		return;
356	priv->reg[1] = d;
357}
358
359static unsigned char parport_uss720_read_control(struct parport *pp)
360{
361	struct parport_uss720_private *priv = pp->private_data;
362	return priv->reg[1] & 0xf; /* Use soft copy */
363}
364
365static unsigned char parport_uss720_frob_control(struct parport *pp, unsigned char mask, unsigned char val)
366{
367	struct parport_uss720_private *priv = pp->private_data;
368	unsigned char d;
369
370	mask &= 0x0f;
371	val &= 0x0f;
372	d = (priv->reg[1] & (~mask)) ^ val;
373	if (set_1284_register(pp, 2, d, GFP_ATOMIC))
374		return 0;
375	priv->reg[1] = d;
376	return d & 0xf;
377}
378
379static unsigned char parport_uss720_read_status(struct parport *pp)
380{
381	unsigned char ret;
382
383	if (get_1284_register(pp, 1, &ret, GFP_ATOMIC))
384		return 0;
385	return ret & 0xf8;
386}
387
388static void parport_uss720_disable_irq(struct parport *pp)
389{
390	struct parport_uss720_private *priv = pp->private_data;
391	unsigned char d;
392
393	d = priv->reg[1] & ~0x10;
394	if (set_1284_register(pp, 2, d, GFP_KERNEL))
395		return;
396	priv->reg[1] = d;
397}
398
399static void parport_uss720_enable_irq(struct parport *pp)
400{
401	struct parport_uss720_private *priv = pp->private_data;
402	unsigned char d;
403
404	d = priv->reg[1] | 0x10;
405	if (set_1284_register(pp, 2, d, GFP_KERNEL))
406		return;
407	priv->reg[1] = d;
408}
409
410static void parport_uss720_data_forward (struct parport *pp)
411{
412	struct parport_uss720_private *priv = pp->private_data;
413	unsigned char d;
414
415	d = priv->reg[1] & ~0x20;
416	if (set_1284_register(pp, 2, d, GFP_KERNEL))
417		return;
418	priv->reg[1] = d;
419}
420
421static void parport_uss720_data_reverse (struct parport *pp)
422{
423	struct parport_uss720_private *priv = pp->private_data;
424	unsigned char d;
425
426	d = priv->reg[1] | 0x20;
427	if (set_1284_register(pp, 2, d, GFP_KERNEL))
428		return;
429	priv->reg[1] = d;
430}
431
432static void parport_uss720_init_state(struct pardevice *dev, struct parport_state *s)
433{
434	s->u.pc.ctr = 0xc | (dev->irq_func ? 0x10 : 0x0);
435	s->u.pc.ecr = 0x24;
436}
437
438static void parport_uss720_save_state(struct parport *pp, struct parport_state *s)
439{
440	struct parport_uss720_private *priv = pp->private_data;
441
442#if 0
443	if (get_1284_register(pp, 2, NULL, GFP_ATOMIC))
444		return;
445#endif
446	s->u.pc.ctr = priv->reg[1];
447	s->u.pc.ecr = priv->reg[2];
448}
449
450static void parport_uss720_restore_state(struct parport *pp, struct parport_state *s)
451{
452	struct parport_uss720_private *priv = pp->private_data;
453
454	set_1284_register(pp, 2, s->u.pc.ctr, GFP_ATOMIC);
455	set_1284_register(pp, 6, s->u.pc.ecr, GFP_ATOMIC);
456	get_1284_register(pp, 2, NULL, GFP_ATOMIC);
457	priv->reg[1] = s->u.pc.ctr;
458	priv->reg[2] = s->u.pc.ecr;
459}
460
461static size_t parport_uss720_epp_read_data(struct parport *pp, void *buf, size_t length, int flags)
462{
463	struct parport_uss720_private *priv = pp->private_data;
464	size_t got = 0;
465
466	if (change_mode(pp, ECR_EPP))
467		return 0;
468	for (; got < length; got++) {
469		if (get_1284_register(pp, 4, (char *)buf, GFP_KERNEL))
470			break;
471		buf++;
472		if (priv->reg[0] & 0x01) {
473			clear_epp_timeout(pp);
474			break;
475		}
476	}
477	change_mode(pp, ECR_PS2);
478	return got;
479}
480
481static size_t parport_uss720_epp_write_data(struct parport *pp, const void *buf, size_t length, int flags)
482{
483#if 0
484	struct parport_uss720_private *priv = pp->private_data;
485	size_t written = 0;
486
487	if (change_mode(pp, ECR_EPP))
488		return 0;
489	for (; written < length; written++) {
490		if (set_1284_register(pp, 4, (char *)buf, GFP_KERNEL))
491			break;
492		((char*)buf)++;
493		if (get_1284_register(pp, 1, NULL, GFP_KERNEL))
494			break;
495		if (priv->reg[0] & 0x01) {
496			clear_epp_timeout(pp);
497			break;
498		}
499	}
500	change_mode(pp, ECR_PS2);
501	return written;
502#else
503	struct parport_uss720_private *priv = pp->private_data;
504	struct usb_device *usbdev = priv->usbdev;
505	int rlen = 0;
506	int i;
507
508	if (!usbdev)
509		return 0;
510	if (change_mode(pp, ECR_EPP))
511		return 0;
512	i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buf, length, &rlen, 20000);
513	if (i)
514		printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %zu rlen %u\n", buf, length, rlen);
515	change_mode(pp, ECR_PS2);
516	return rlen;
517#endif
518}
519
520static size_t parport_uss720_epp_read_addr(struct parport *pp, void *buf, size_t length, int flags)
521{
522	struct parport_uss720_private *priv = pp->private_data;
523	size_t got = 0;
524
525	if (change_mode(pp, ECR_EPP))
526		return 0;
527	for (; got < length; got++) {
528		if (get_1284_register(pp, 3, (char *)buf, GFP_KERNEL))
529			break;
530		buf++;
531		if (priv->reg[0] & 0x01) {
532			clear_epp_timeout(pp);
533			break;
534		}
535	}
536	change_mode(pp, ECR_PS2);
537	return got;
538}
539
540static size_t parport_uss720_epp_write_addr(struct parport *pp, const void *buf, size_t length, int flags)
541{
542	struct parport_uss720_private *priv = pp->private_data;
543	size_t written = 0;
544
545	if (change_mode(pp, ECR_EPP))
546		return 0;
547	for (; written < length; written++) {
548		if (set_1284_register(pp, 3, *(char *)buf, GFP_KERNEL))
549			break;
550		buf++;
551		if (get_1284_register(pp, 1, NULL, GFP_KERNEL))
552			break;
553		if (priv->reg[0] & 0x01) {
554			clear_epp_timeout(pp);
555			break;
556		}
557	}
558	change_mode(pp, ECR_PS2);
559	return written;
560}
561
562static size_t parport_uss720_ecp_write_data(struct parport *pp, const void *buffer, size_t len, int flags)
563{
564	struct parport_uss720_private *priv = pp->private_data;
565	struct usb_device *usbdev = priv->usbdev;
566	int rlen = 0;
567	int i;
568
569	if (!usbdev)
570		return 0;
571	if (change_mode(pp, ECR_ECP))
572		return 0;
573	i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buffer, len, &rlen, 20000);
574	if (i)
575		printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %zu rlen %u\n", buffer, len, rlen);
576	change_mode(pp, ECR_PS2);
577	return rlen;
578}
579
580static size_t parport_uss720_ecp_read_data(struct parport *pp, 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 = 0;
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_rcvbulkpipe(usbdev, 2), buffer, len, &rlen, 20000);
592	if (i)
593		printk(KERN_ERR "uss720: recvbulk ep 2 buf %p len %zu rlen %u\n", buffer, len, rlen);
594	change_mode(pp, ECR_PS2);
595	return rlen;
596}
597
598static size_t parport_uss720_ecp_write_addr(struct parport *pp, const void *buffer, size_t len, int flags)
599{
600	size_t written = 0;
601
602	if (change_mode(pp, ECR_ECP))
603		return 0;
604	for (; written < len; written++) {
605		if (set_1284_register(pp, 5, *(char *)buffer, GFP_KERNEL))
606			break;
607		buffer++;
608	}
609	change_mode(pp, ECR_PS2);
610	return written;
611}
612
613static size_t parport_uss720_write_compat(struct parport *pp, const void *buffer, size_t len, int flags)
614{
615	struct parport_uss720_private *priv = pp->private_data;
616	struct usb_device *usbdev = priv->usbdev;
617	int rlen = 0;
618	int i;
619
620	if (!usbdev)
621		return 0;
622	if (change_mode(pp, ECR_PPF))
623		return 0;
624	i = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, 1), (void *)buffer, len, &rlen, 20000);
625	if (i)
626		printk(KERN_ERR "uss720: sendbulk ep 1 buf %p len %zu rlen %u\n", buffer, len, rlen);
627	change_mode(pp, ECR_PS2);
628	return rlen;
629}
630
631/* --------------------------------------------------------------------- */
632
633static struct parport_operations parport_uss720_ops =
634{
635	.owner =		THIS_MODULE,
636	.write_data =		parport_uss720_write_data,
637	.read_data =		parport_uss720_read_data,
638
639	.write_control =	parport_uss720_write_control,
640	.read_control =		parport_uss720_read_control,
641	.frob_control =		parport_uss720_frob_control,
642
643	.read_status =		parport_uss720_read_status,
644
645	.enable_irq =		parport_uss720_enable_irq,
646	.disable_irq =		parport_uss720_disable_irq,
647
648	.data_forward =		parport_uss720_data_forward,
649	.data_reverse =		parport_uss720_data_reverse,
650
651	.init_state =		parport_uss720_init_state,
652	.save_state =		parport_uss720_save_state,
653	.restore_state =	parport_uss720_restore_state,
654
655	.epp_write_data =	parport_uss720_epp_write_data,
656	.epp_read_data =	parport_uss720_epp_read_data,
657	.epp_write_addr =	parport_uss720_epp_write_addr,
658	.epp_read_addr =	parport_uss720_epp_read_addr,
659
660	.ecp_write_data =	parport_uss720_ecp_write_data,
661	.ecp_read_data =	parport_uss720_ecp_read_data,
662	.ecp_write_addr =	parport_uss720_ecp_write_addr,
663
664	.compat_write_data =	parport_uss720_write_compat,
665	.nibble_read_data =	parport_ieee1284_read_nibble,
666	.byte_read_data =	parport_ieee1284_read_byte,
667};
668
669/* --------------------------------------------------------------------- */
670
671static int uss720_probe(struct usb_interface *intf,
672			const struct usb_device_id *id)
673{
674	struct usb_device *usbdev = usb_get_dev(interface_to_usbdev(intf));
675	struct usb_host_interface *interface;
676	struct usb_endpoint_descriptor *epd;
677	struct parport_uss720_private *priv;
678	struct parport *pp;
679	unsigned char reg;
680	int i;
681
682	dev_dbg(&intf->dev, "probe: vendor id 0x%x, device id 0x%x\n",
683		le16_to_cpu(usbdev->descriptor.idVendor),
684		le16_to_cpu(usbdev->descriptor.idProduct));
685
686	/* our known interfaces have 3 alternate settings */
687	if (intf->num_altsetting != 3) {
688		usb_put_dev(usbdev);
689		return -ENODEV;
690	}
691	i = usb_set_interface(usbdev, intf->altsetting->desc.bInterfaceNumber, 2);
692	dev_dbg(&intf->dev, "set interface result %d\n", i);
693
694	interface = intf->cur_altsetting;
695
696	if (interface->desc.bNumEndpoints < 3) {
697		usb_put_dev(usbdev);
698		return -ENODEV;
699	}
700
701	/*
702	 * Allocate parport interface
703	 */
704	priv = kzalloc(sizeof(struct parport_uss720_private), GFP_KERNEL);
705	if (!priv) {
706		usb_put_dev(usbdev);
707		return -ENOMEM;
708	}
709	priv->pp = NULL;
710	priv->usbdev = usbdev;
711	kref_init(&priv->ref_count);
712	spin_lock_init(&priv->asynclock);
713	INIT_LIST_HEAD(&priv->asynclist);
714	pp = parport_register_port(0, PARPORT_IRQ_NONE, PARPORT_DMA_NONE, &parport_uss720_ops);
715	if (!pp) {
716		printk(KERN_WARNING "uss720: could not register parport\n");
717		goto probe_abort;
718	}
719
720	priv->pp = pp;
721	pp->private_data = priv;
722	pp->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_TRISTATE | PARPORT_MODE_EPP | PARPORT_MODE_ECP | PARPORT_MODE_COMPAT;
723
724	/* set the USS720 control register to manual mode, no ECP compression, enable all ints */
725	set_1284_register(pp, 7, 0x00, GFP_KERNEL);
726	set_1284_register(pp, 6, 0x30, GFP_KERNEL);  /* PS/2 mode */
727	set_1284_register(pp, 2, 0x0c, GFP_KERNEL);
728	/* debugging */
729	get_1284_register(pp, 0, &reg, GFP_KERNEL);
730	dev_dbg(&intf->dev, "reg: %7ph\n", priv->reg);
731
732	i = usb_find_last_int_in_endpoint(interface, &epd);
733	if (!i) {
734		dev_dbg(&intf->dev, "epaddr %d interval %d\n",
735				epd->bEndpointAddress, epd->bInterval);
736	}
737	parport_announce_port(pp);
738
739	usb_set_intfdata(intf, pp);
740	return 0;
741
742probe_abort:
743	kill_all_async_requests_priv(priv);
744	kref_put(&priv->ref_count, destroy_priv);
745	return -ENODEV;
746}
747
748static void uss720_disconnect(struct usb_interface *intf)
749{
750	struct parport *pp = usb_get_intfdata(intf);
751	struct parport_uss720_private *priv;
752
753	dev_dbg(&intf->dev, "disconnect\n");
754	usb_set_intfdata(intf, NULL);
755	if (pp) {
756		priv = pp->private_data;
757		priv->pp = NULL;
758		dev_dbg(&intf->dev, "parport_remove_port\n");
759		parport_remove_port(pp);
760		parport_put_port(pp);
761		kill_all_async_requests_priv(priv);
762		kref_put(&priv->ref_count, destroy_priv);
763	}
764	dev_dbg(&intf->dev, "disconnect done\n");
765}
766
767/* table of cables that work through this driver */
768static const struct usb_device_id uss720_table[] = {
769	{ USB_DEVICE(0x047e, 0x1001) },
770	{ USB_DEVICE(0x04b8, 0x0002) },
771	{ USB_DEVICE(0x04b8, 0x0003) },
772	{ USB_DEVICE(0x050d, 0x0002) },
773	{ USB_DEVICE(0x050d, 0x1202) },
774	{ USB_DEVICE(0x0557, 0x2001) },
775	{ USB_DEVICE(0x05ab, 0x0002) },
776	{ USB_DEVICE(0x06c6, 0x0100) },
777	{ USB_DEVICE(0x0729, 0x1284) },
778	{ USB_DEVICE(0x1293, 0x0002) },
779	{ }						/* Terminating entry */
780};
781
782MODULE_DEVICE_TABLE (usb, uss720_table);
783
784
785static struct usb_driver uss720_driver = {
786	.name =		"uss720",
787	.probe =	uss720_probe,
788	.disconnect =	uss720_disconnect,
789	.id_table =	uss720_table,
790};
791
792/* --------------------------------------------------------------------- */
793
794MODULE_AUTHOR(DRIVER_AUTHOR);
795MODULE_DESCRIPTION(DRIVER_DESC);
796MODULE_LICENSE("GPL");
797
798static int __init uss720_init(void)
799{
800	int retval;
801	retval = usb_register(&uss720_driver);
802	if (retval)
803		goto out;
804
805	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");
806	printk(KERN_INFO KBUILD_MODNAME ": NOTE: this is a special purpose "
807	       "driver to allow nonstandard\n");
808	printk(KERN_INFO KBUILD_MODNAME ": protocols (eg. bitbang) over "
809	       "USS720 usb to parallel cables\n");
810	printk(KERN_INFO KBUILD_MODNAME ": If you just want to connect to a "
811	       "printer, use usblp instead\n");
812out:
813	return retval;
814}
815
816static void __exit uss720_cleanup(void)
817{
818	usb_deregister(&uss720_driver);
819}
820
821module_init(uss720_init);
822module_exit(uss720_cleanup);
823
824/* --------------------------------------------------------------------- */
825