xref: /freebsd/sys/dev/usb/serial/ulpt.c (revision 7aa383846770374466b1dcb2cefd71bde9acf463)
1 #include <sys/cdefs.h>
2 __FBSDID("$FreeBSD$");
3 
4 /*	$NetBSD: ulpt.c,v 1.60 2003/10/04 21:19:50 augustss Exp $	*/
5 
6 /*-
7  * Copyright (c) 1998, 2003 The NetBSD Foundation, Inc.
8  * All rights reserved.
9  *
10  * This code is derived from software contributed to The NetBSD Foundation
11  * by Lennart Augustsson (lennart@augustsson.net) at
12  * Carlstedt Research & Technology.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
24  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
25  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
26  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
27  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33  * POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /*
37  * Printer Class spec: http://www.usb.org/developers/data/devclass/usbprint109.PDF
38  * Printer Class spec: http://www.usb.org/developers/devclass_docs/usbprint11.pdf
39  */
40 
41 #include <sys/stdint.h>
42 #include <sys/stddef.h>
43 #include <sys/param.h>
44 #include <sys/queue.h>
45 #include <sys/types.h>
46 #include <sys/systm.h>
47 #include <sys/kernel.h>
48 #include <sys/bus.h>
49 #include <sys/linker_set.h>
50 #include <sys/module.h>
51 #include <sys/lock.h>
52 #include <sys/mutex.h>
53 #include <sys/condvar.h>
54 #include <sys/sysctl.h>
55 #include <sys/sx.h>
56 #include <sys/unistd.h>
57 #include <sys/callout.h>
58 #include <sys/malloc.h>
59 #include <sys/priv.h>
60 #include <sys/syslog.h>
61 #include <sys/selinfo.h>
62 #include <sys/conf.h>
63 #include <sys/fcntl.h>
64 
65 #include <dev/usb/usb.h>
66 #include <dev/usb/usbdi.h>
67 #include <dev/usb/usbdi_util.h>
68 #include <dev/usb/usbhid.h>
69 #include "usbdevs.h"
70 
71 #define	USB_DEBUG_VAR ulpt_debug
72 #include <dev/usb/usb_debug.h>
73 #include <dev/usb/usb_process.h>
74 
75 #ifdef USB_DEBUG
76 static int ulpt_debug = 0;
77 
78 SYSCTL_NODE(_hw_usb, OID_AUTO, ulpt, CTLFLAG_RW, 0, "USB ulpt");
79 SYSCTL_INT(_hw_usb_ulpt, OID_AUTO, debug, CTLFLAG_RW,
80     &ulpt_debug, 0, "Debug level");
81 #endif
82 
83 #define	ULPT_BSIZE		(1<<15)	/* bytes */
84 #define	ULPT_IFQ_MAXLEN         2	/* units */
85 
86 #define	UR_GET_DEVICE_ID        0x00
87 #define	UR_GET_PORT_STATUS      0x01
88 #define	UR_SOFT_RESET           0x02
89 
90 #define	LPS_NERR		0x08	/* printer no error */
91 #define	LPS_SELECT		0x10	/* printer selected */
92 #define	LPS_NOPAPER		0x20	/* printer out of paper */
93 #define	LPS_INVERT      (LPS_SELECT|LPS_NERR)
94 #define	LPS_MASK        (LPS_SELECT|LPS_NERR|LPS_NOPAPER)
95 
96 enum {
97 	ULPT_BULK_DT_WR,
98 	ULPT_BULK_DT_RD,
99 	ULPT_INTR_DT_RD,
100 	ULPT_N_TRANSFER,
101 };
102 
103 struct ulpt_softc {
104 	struct usb_fifo_sc sc_fifo;
105 	struct usb_fifo_sc sc_fifo_noreset;
106 	struct mtx sc_mtx;
107 	struct usb_callout sc_watchdog;
108 
109 	device_t sc_dev;
110 	struct usb_device *sc_udev;
111 	struct usb_fifo *sc_fifo_open[2];
112 	struct usb_xfer *sc_xfer[ULPT_N_TRANSFER];
113 
114 	int	sc_fflags;		/* current open flags, FREAD and
115 					 * FWRITE */
116 	uint8_t	sc_iface_no;
117 	uint8_t	sc_last_status;
118 	uint8_t	sc_zlps;		/* number of consequtive zero length
119 					 * packets received */
120 };
121 
122 /* prototypes */
123 
124 static device_probe_t ulpt_probe;
125 static device_attach_t ulpt_attach;
126 static device_detach_t ulpt_detach;
127 
128 static usb_callback_t ulpt_write_callback;
129 static usb_callback_t ulpt_read_callback;
130 static usb_callback_t ulpt_status_callback;
131 
132 static void	ulpt_reset(struct ulpt_softc *);
133 static void	ulpt_watchdog(void *);
134 
135 static usb_fifo_close_t ulpt_close;
136 static usb_fifo_cmd_t ulpt_start_read;
137 static usb_fifo_cmd_t ulpt_start_write;
138 static usb_fifo_cmd_t ulpt_stop_read;
139 static usb_fifo_cmd_t ulpt_stop_write;
140 static usb_fifo_ioctl_t ulpt_ioctl;
141 static usb_fifo_open_t ulpt_open;
142 static usb_fifo_open_t unlpt_open;
143 
144 static struct usb_fifo_methods ulpt_fifo_methods = {
145 	.f_close = &ulpt_close,
146 	.f_ioctl = &ulpt_ioctl,
147 	.f_open = &ulpt_open,
148 	.f_start_read = &ulpt_start_read,
149 	.f_start_write = &ulpt_start_write,
150 	.f_stop_read = &ulpt_stop_read,
151 	.f_stop_write = &ulpt_stop_write,
152 	.basename[0] = "ulpt",
153 };
154 
155 static struct usb_fifo_methods unlpt_fifo_methods = {
156 	.f_close = &ulpt_close,
157 	.f_ioctl = &ulpt_ioctl,
158 	.f_open = &unlpt_open,
159 	.f_start_read = &ulpt_start_read,
160 	.f_start_write = &ulpt_start_write,
161 	.f_stop_read = &ulpt_stop_read,
162 	.f_stop_write = &ulpt_stop_write,
163 	.basename[0] = "unlpt",
164 };
165 
166 static void
167 ulpt_reset(struct ulpt_softc *sc)
168 {
169 	struct usb_device_request req;
170 
171 	DPRINTFN(2, "\n");
172 
173 	req.bRequest = UR_SOFT_RESET;
174 	USETW(req.wValue, 0);
175 	USETW(req.wIndex, sc->sc_iface_no);
176 	USETW(req.wLength, 0);
177 
178 	/*
179 	 * There was a mistake in the USB printer 1.0 spec that gave the
180 	 * request type as UT_WRITE_CLASS_OTHER; it should have been
181 	 * UT_WRITE_CLASS_INTERFACE.  Many printers use the old one,
182 	 * so we try both.
183 	 */
184 
185 	mtx_lock(&sc->sc_mtx);
186 	req.bmRequestType = UT_WRITE_CLASS_OTHER;
187 	if (usbd_do_request_flags(sc->sc_udev, &sc->sc_mtx,
188 	    &req, NULL, 0, NULL, 2 * USB_MS_HZ)) {	/* 1.0 */
189 		req.bmRequestType = UT_WRITE_CLASS_INTERFACE;
190 		if (usbd_do_request_flags(sc->sc_udev, &sc->sc_mtx,
191 		    &req, NULL, 0, NULL, 2 * USB_MS_HZ)) {	/* 1.1 */
192 			/* ignore error */
193 		}
194 	}
195 	mtx_unlock(&sc->sc_mtx);
196 }
197 
198 static void
199 ulpt_write_callback(struct usb_xfer *xfer, usb_error_t error)
200 {
201 	struct ulpt_softc *sc = usbd_xfer_softc(xfer);
202 	struct usb_fifo *f = sc->sc_fifo_open[USB_FIFO_TX];
203 	struct usb_page_cache *pc;
204 	int actlen, max;
205 
206 	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
207 
208 	if (f == NULL) {
209 		/* should not happen */
210 		DPRINTF("no FIFO\n");
211 		return;
212 	}
213 	DPRINTF("state=0x%x actlen=%d\n", USB_GET_STATE(xfer), actlen);
214 
215 	switch (USB_GET_STATE(xfer)) {
216 	case USB_ST_TRANSFERRED:
217 	case USB_ST_SETUP:
218 tr_setup:
219 		pc = usbd_xfer_get_frame(xfer, 0);
220 		max = usbd_xfer_max_len(xfer);
221 		if (usb_fifo_get_data(f, pc, 0, max, &actlen, 0)) {
222 			usbd_xfer_set_frame_len(xfer, 0, actlen);
223 			usbd_transfer_submit(xfer);
224 		}
225 		break;
226 
227 	default:			/* Error */
228 		if (error != USB_ERR_CANCELLED) {
229 			/* try to clear stall first */
230 			usbd_xfer_set_stall(xfer);
231 			goto tr_setup;
232 		}
233 		break;
234 	}
235 }
236 
237 static void
238 ulpt_read_callback(struct usb_xfer *xfer, usb_error_t error)
239 {
240 	struct ulpt_softc *sc = usbd_xfer_softc(xfer);
241 	struct usb_fifo *f = sc->sc_fifo_open[USB_FIFO_RX];
242 	struct usb_page_cache *pc;
243 	int actlen;
244 
245 	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
246 
247 	if (f == NULL) {
248 		/* should not happen */
249 		DPRINTF("no FIFO\n");
250 		return;
251 	}
252 	DPRINTF("state=0x%x\n", USB_GET_STATE(xfer));
253 
254 	switch (USB_GET_STATE(xfer)) {
255 	case USB_ST_TRANSFERRED:
256 
257 		if (actlen == 0) {
258 
259 			if (sc->sc_zlps == 4) {
260 				/* enable BULK throttle */
261 				usbd_xfer_set_interval(xfer, 500); /* ms */
262 			} else {
263 				sc->sc_zlps++;
264 			}
265 		} else {
266 			/* disable BULK throttle */
267 
268 			usbd_xfer_set_interval(xfer, 0);
269 			sc->sc_zlps = 0;
270 		}
271 
272 		pc = usbd_xfer_get_frame(xfer, 0);
273 		usb_fifo_put_data(f, pc, 0, actlen, 1);
274 
275 	case USB_ST_SETUP:
276 tr_setup:
277 		if (usb_fifo_put_bytes_max(f) != 0) {
278 			usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
279 			usbd_transfer_submit(xfer);
280 		}
281 		break;
282 
283 	default:			/* Error */
284 		/* disable BULK throttle */
285 		usbd_xfer_set_interval(xfer, 0);
286 		sc->sc_zlps = 0;
287 
288 		if (error != USB_ERR_CANCELLED) {
289 			/* try to clear stall first */
290 			usbd_xfer_set_stall(xfer);
291 			goto tr_setup;
292 		}
293 		break;
294 	}
295 }
296 
297 static void
298 ulpt_status_callback(struct usb_xfer *xfer, usb_error_t error)
299 {
300 	struct ulpt_softc *sc = usbd_xfer_softc(xfer);
301 	struct usb_device_request req;
302 	struct usb_page_cache *pc;
303 	uint8_t cur_status;
304 	uint8_t new_status;
305 
306 	switch (USB_GET_STATE(xfer)) {
307 	case USB_ST_TRANSFERRED:
308 
309 		pc = usbd_xfer_get_frame(xfer, 1);
310 		usbd_copy_out(pc, 0, &cur_status, 1);
311 
312 		cur_status = (cur_status ^ LPS_INVERT) & LPS_MASK;
313 		new_status = cur_status & ~sc->sc_last_status;
314 		sc->sc_last_status = cur_status;
315 
316 		if (new_status & LPS_SELECT)
317 			log(LOG_NOTICE, "%s: offline\n",
318 			    device_get_nameunit(sc->sc_dev));
319 		else if (new_status & LPS_NOPAPER)
320 			log(LOG_NOTICE, "%s: out of paper\n",
321 			    device_get_nameunit(sc->sc_dev));
322 		else if (new_status & LPS_NERR)
323 			log(LOG_NOTICE, "%s: output error\n",
324 			    device_get_nameunit(sc->sc_dev));
325 		break;
326 
327 	case USB_ST_SETUP:
328 		req.bmRequestType = UT_READ_CLASS_INTERFACE;
329 		req.bRequest = UR_GET_PORT_STATUS;
330 		USETW(req.wValue, 0);
331 		req.wIndex[0] = sc->sc_iface_no;
332 		req.wIndex[1] = 0;
333 		USETW(req.wLength, 1);
334 
335 		pc = usbd_xfer_get_frame(xfer, 0);
336 		usbd_copy_in(pc, 0, &req, sizeof(req));
337 
338 		usbd_xfer_set_frame_len(xfer, 0, sizeof(req));
339 		usbd_xfer_set_frame_len(xfer, 1, 1);
340 		usbd_xfer_set_frames(xfer, 2);
341 		usbd_transfer_submit(xfer);
342 		break;
343 
344 	default:			/* Error */
345 		DPRINTF("error=%s\n", usbd_errstr(error));
346 		if (error != USB_ERR_CANCELLED) {
347 			/* wait for next watchdog timeout */
348 		}
349 		break;
350 	}
351 }
352 
353 static const struct usb_config ulpt_config[ULPT_N_TRANSFER] = {
354 	[ULPT_BULK_DT_WR] = {
355 		.type = UE_BULK,
356 		.endpoint = UE_ADDR_ANY,
357 		.direction = UE_DIR_OUT,
358 		.bufsize = ULPT_BSIZE,
359 		.flags = {.pipe_bof = 1,.proxy_buffer = 1},
360 		.callback = &ulpt_write_callback,
361 	},
362 
363 	[ULPT_BULK_DT_RD] = {
364 		.type = UE_BULK,
365 		.endpoint = UE_ADDR_ANY,
366 		.direction = UE_DIR_IN,
367 		.bufsize = ULPT_BSIZE,
368 		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,.proxy_buffer = 1},
369 		.callback = &ulpt_read_callback,
370 	},
371 
372 	[ULPT_INTR_DT_RD] = {
373 		.type = UE_CONTROL,
374 		.endpoint = 0x00,	/* Control pipe */
375 		.direction = UE_DIR_ANY,
376 		.bufsize = sizeof(struct usb_device_request) + 1,
377 		.callback = &ulpt_status_callback,
378 		.timeout = 1000,	/* 1 second */
379 	},
380 };
381 
382 static void
383 ulpt_start_read(struct usb_fifo *fifo)
384 {
385 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
386 
387 	usbd_transfer_start(sc->sc_xfer[ULPT_BULK_DT_RD]);
388 }
389 
390 static void
391 ulpt_stop_read(struct usb_fifo *fifo)
392 {
393 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
394 
395 	usbd_transfer_stop(sc->sc_xfer[ULPT_BULK_DT_RD]);
396 }
397 
398 static void
399 ulpt_start_write(struct usb_fifo *fifo)
400 {
401 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
402 
403 	usbd_transfer_start(sc->sc_xfer[ULPT_BULK_DT_WR]);
404 }
405 
406 static void
407 ulpt_stop_write(struct usb_fifo *fifo)
408 {
409 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
410 
411 	usbd_transfer_stop(sc->sc_xfer[ULPT_BULK_DT_WR]);
412 }
413 
414 static int
415 ulpt_open(struct usb_fifo *fifo, int fflags)
416 {
417 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
418 
419 	/* we assume that open is a serial process */
420 
421 	if (sc->sc_fflags == 0) {
422 
423 		/* reset USB paralell port */
424 
425 		ulpt_reset(sc);
426 	}
427 	return (unlpt_open(fifo, fflags));
428 }
429 
430 static int
431 unlpt_open(struct usb_fifo *fifo, int fflags)
432 {
433 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
434 
435 	if (sc->sc_fflags & fflags) {
436 		return (EBUSY);
437 	}
438 	if (fflags & FREAD) {
439 		/* clear stall first */
440 		mtx_lock(&sc->sc_mtx);
441 		usbd_xfer_set_stall(sc->sc_xfer[ULPT_BULK_DT_RD]);
442 		mtx_unlock(&sc->sc_mtx);
443 		if (usb_fifo_alloc_buffer(fifo,
444 		    usbd_xfer_max_len(sc->sc_xfer[ULPT_BULK_DT_RD]),
445 		    ULPT_IFQ_MAXLEN)) {
446 			return (ENOMEM);
447 		}
448 		/* set which FIFO is opened */
449 		sc->sc_fifo_open[USB_FIFO_RX] = fifo;
450 	}
451 	if (fflags & FWRITE) {
452 		/* clear stall first */
453 		mtx_lock(&sc->sc_mtx);
454 		usbd_xfer_set_stall(sc->sc_xfer[ULPT_BULK_DT_WR]);
455 		mtx_unlock(&sc->sc_mtx);
456 		if (usb_fifo_alloc_buffer(fifo,
457 		    usbd_xfer_max_len(sc->sc_xfer[ULPT_BULK_DT_WR]),
458 		    ULPT_IFQ_MAXLEN)) {
459 			return (ENOMEM);
460 		}
461 		/* set which FIFO is opened */
462 		sc->sc_fifo_open[USB_FIFO_TX] = fifo;
463 	}
464 	sc->sc_fflags |= fflags & (FREAD | FWRITE);
465 	return (0);
466 }
467 
468 static void
469 ulpt_close(struct usb_fifo *fifo, int fflags)
470 {
471 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
472 
473 	sc->sc_fflags &= ~(fflags & (FREAD | FWRITE));
474 
475 	if (fflags & (FREAD | FWRITE)) {
476 		usb_fifo_free_buffer(fifo);
477 	}
478 }
479 
480 static int
481 ulpt_ioctl(struct usb_fifo *fifo, u_long cmd, void *data,
482     int fflags)
483 {
484 	return (ENODEV);
485 }
486 
487 static int
488 ulpt_probe(device_t dev)
489 {
490 	struct usb_attach_arg *uaa = device_get_ivars(dev);
491 
492 	DPRINTFN(11, "\n");
493 
494 	if (uaa->usb_mode != USB_MODE_HOST) {
495 		return (ENXIO);
496 	}
497 	if ((uaa->info.bInterfaceClass == UICLASS_PRINTER) &&
498 	    (uaa->info.bInterfaceSubClass == UISUBCLASS_PRINTER) &&
499 	    ((uaa->info.bInterfaceProtocol == UIPROTO_PRINTER_UNI) ||
500 	    (uaa->info.bInterfaceProtocol == UIPROTO_PRINTER_BI) ||
501 	    (uaa->info.bInterfaceProtocol == UIPROTO_PRINTER_1284))) {
502 		return (0);
503 	}
504 	return (ENXIO);
505 }
506 
507 static int
508 ulpt_attach(device_t dev)
509 {
510 	struct usb_attach_arg *uaa = device_get_ivars(dev);
511 	struct ulpt_softc *sc = device_get_softc(dev);
512 	struct usb_interface_descriptor *id;
513 	int unit = device_get_unit(dev);
514 	int error;
515 	uint8_t iface_index = uaa->info.bIfaceIndex;
516 	uint8_t alt_index;
517 
518 	DPRINTFN(11, "sc=%p\n", sc);
519 
520 	sc->sc_dev = dev;
521 	sc->sc_udev = uaa->device;
522 
523 	device_set_usb_desc(dev);
524 
525 	mtx_init(&sc->sc_mtx, "ulpt lock", NULL, MTX_DEF | MTX_RECURSE);
526 
527 	usb_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);
528 
529 	/* search through all the descriptors looking for bidir mode */
530 
531 	id = usbd_get_interface_descriptor(uaa->iface);
532 	alt_index = 0 - 1;
533 	while (1) {
534 		if (id == NULL) {
535 			break;
536 		}
537 		if ((id->bDescriptorType == UDESC_INTERFACE) &&
538 		    (id->bLength >= sizeof(*id))) {
539 			if (id->bInterfaceNumber != uaa->info.bIfaceNum) {
540 				break;
541 			} else {
542 				alt_index++;
543 				if ((id->bInterfaceClass == UICLASS_PRINTER) &&
544 				    (id->bInterfaceSubClass == UISUBCLASS_PRINTER) &&
545 				    (id->bInterfaceProtocol == UIPROTO_PRINTER_BI)) {
546 					goto found;
547 				}
548 			}
549 		}
550 		id = (void *)usb_desc_foreach(
551 		    usbd_get_config_descriptor(uaa->device), (void *)id);
552 	}
553 	goto detach;
554 
555 found:
556 
557 	DPRINTF("setting alternate "
558 	    "config number: %d\n", alt_index);
559 
560 	if (alt_index) {
561 
562 		error = usbd_set_alt_interface_index
563 		    (uaa->device, iface_index, alt_index);
564 
565 		if (error) {
566 			DPRINTF("could not set alternate "
567 			    "config, error=%s\n", usbd_errstr(error));
568 			goto detach;
569 		}
570 	}
571 	sc->sc_iface_no = id->bInterfaceNumber;
572 
573 	error = usbd_transfer_setup(uaa->device, &iface_index,
574 	    sc->sc_xfer, ulpt_config, ULPT_N_TRANSFER,
575 	    sc, &sc->sc_mtx);
576 	if (error) {
577 		DPRINTF("error=%s\n", usbd_errstr(error));
578 		goto detach;
579 	}
580 	device_printf(sc->sc_dev, "using bi-directional mode\n");
581 
582 #if 0
583 /*
584  * This code is disabled because for some mysterious reason it causes
585  * printing not to work.  But only sometimes, and mostly with
586  * UHCI and less often with OHCI.  *sigh*
587  */
588 	{
589 		struct usb_config_descriptor *cd = usbd_get_config_descriptor(dev);
590 		struct usb_device_request req;
591 		int len, alen;
592 
593 		req.bmRequestType = UT_READ_CLASS_INTERFACE;
594 		req.bRequest = UR_GET_DEVICE_ID;
595 		USETW(req.wValue, cd->bConfigurationValue);
596 		USETW2(req.wIndex, id->bInterfaceNumber, id->bAlternateSetting);
597 		USETW(req.wLength, sizeof devinfo - 1);
598 		error = usbd_do_request_flags(dev, &req, devinfo, USB_SHORT_XFER_OK,
599 		    &alen, USB_DEFAULT_TIMEOUT);
600 		if (error) {
601 			device_printf(sc->sc_dev, "cannot get device id\n");
602 		} else if (alen <= 2) {
603 			device_printf(sc->sc_dev, "empty device id, no "
604 			    "printer connected?\n");
605 		} else {
606 			/* devinfo now contains an IEEE-1284 device ID */
607 			len = ((devinfo[0] & 0xff) << 8) | (devinfo[1] & 0xff);
608 			if (len > sizeof devinfo - 3)
609 				len = sizeof devinfo - 3;
610 			devinfo[len] = 0;
611 			printf("%s: device id <", device_get_nameunit(sc->sc_dev));
612 			ieee1284_print_id(devinfo + 2);
613 			printf(">\n");
614 		}
615 	}
616 #endif
617 
618 	error = usb_fifo_attach(uaa->device, sc, &sc->sc_mtx,
619 	    &ulpt_fifo_methods, &sc->sc_fifo,
620 	    unit, 0 - 1, uaa->info.bIfaceIndex,
621 	    UID_ROOT, GID_OPERATOR, 0644);
622 	if (error) {
623 		goto detach;
624 	}
625 	error = usb_fifo_attach(uaa->device, sc, &sc->sc_mtx,
626 	    &unlpt_fifo_methods, &sc->sc_fifo_noreset,
627 	    unit, 0 - 1, uaa->info.bIfaceIndex,
628 	    UID_ROOT, GID_OPERATOR, 0644);
629 	if (error) {
630 		goto detach;
631 	}
632 	/* start reading of status */
633 
634 	mtx_lock(&sc->sc_mtx);
635 	ulpt_watchdog(sc);
636 	mtx_unlock(&sc->sc_mtx);
637 	return (0);
638 
639 detach:
640 	ulpt_detach(dev);
641 	return (ENOMEM);
642 }
643 
644 static int
645 ulpt_detach(device_t dev)
646 {
647 	struct ulpt_softc *sc = device_get_softc(dev);
648 
649 	DPRINTF("sc=%p\n", sc);
650 
651 	usb_fifo_detach(&sc->sc_fifo);
652 	usb_fifo_detach(&sc->sc_fifo_noreset);
653 
654 	mtx_lock(&sc->sc_mtx);
655 	usb_callout_stop(&sc->sc_watchdog);
656 	mtx_unlock(&sc->sc_mtx);
657 
658 	usbd_transfer_unsetup(sc->sc_xfer, ULPT_N_TRANSFER);
659 	usb_callout_drain(&sc->sc_watchdog);
660 	mtx_destroy(&sc->sc_mtx);
661 
662 	return (0);
663 }
664 
665 #if 0
666 /* XXX This does not belong here. */
667 
668 /*
669  * Compare two strings until the second ends.
670  */
671 
672 static uint8_t
673 ieee1284_compare(const char *a, const char *b)
674 {
675 	while (1) {
676 
677 		if (*b == 0) {
678 			break;
679 		}
680 		if (*a != *b) {
681 			return 1;
682 		}
683 		b++;
684 		a++;
685 	}
686 	return 0;
687 }
688 
689 /*
690  * Print select parts of an IEEE 1284 device ID.
691  */
692 void
693 ieee1284_print_id(char *str)
694 {
695 	char *p, *q;
696 
697 	for (p = str - 1; p; p = strchr(p, ';')) {
698 		p++;			/* skip ';' */
699 		if (ieee1284_compare(p, "MFG:") == 0 ||
700 		    ieee1284_compare(p, "MANUFACTURER:") == 0 ||
701 		    ieee1284_compare(p, "MDL:") == 0 ||
702 		    ieee1284_compare(p, "MODEL:") == 0) {
703 			q = strchr(p, ';');
704 			if (q)
705 				printf("%.*s", (int)(q - p + 1), p);
706 		}
707 	}
708 }
709 
710 #endif
711 
712 static void
713 ulpt_watchdog(void *arg)
714 {
715 	struct ulpt_softc *sc = arg;
716 
717 	mtx_assert(&sc->sc_mtx, MA_OWNED);
718 
719 	/*
720 	 * Only read status while the device is not opened, due to
721 	 * possible hardware or firmware bug in some printers.
722 	 */
723 	if (sc->sc_fflags == 0)
724 		usbd_transfer_start(sc->sc_xfer[ULPT_INTR_DT_RD]);
725 
726 	usb_callout_reset(&sc->sc_watchdog,
727 	    hz, &ulpt_watchdog, sc);
728 }
729 
730 static devclass_t ulpt_devclass;
731 
732 static device_method_t ulpt_methods[] = {
733 	DEVMETHOD(device_probe, ulpt_probe),
734 	DEVMETHOD(device_attach, ulpt_attach),
735 	DEVMETHOD(device_detach, ulpt_detach),
736 	{0, 0}
737 };
738 
739 static driver_t ulpt_driver = {
740 	.name = "ulpt",
741 	.methods = ulpt_methods,
742 	.size = sizeof(struct ulpt_softc),
743 };
744 
745 DRIVER_MODULE(ulpt, uhub, ulpt_driver, ulpt_devclass, NULL, 0);
746 MODULE_DEPEND(ulpt, usb, 1, 1, 1);
747 MODULE_DEPEND(ulpt, ucom, 1, 1, 1);
748