xref: /freebsd/sys/dev/usb/serial/ulpt.c (revision 566a751354a439384a12dd3f4b43ff3b55ddf9a8)
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  * 3. All advertising materials mentioning features or use of this software
23  *    must display the following acknowledgement:
24  *        This product includes software developed by the NetBSD
25  *        Foundation, Inc. and its contributors.
26  * 4. Neither the name of The NetBSD Foundation nor the names of its
27  *    contributors may be used to endorse or promote products derived
28  *    from this software without specific prior written permission.
29  *
30  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
31  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
32  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
33  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
34  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
35  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
36  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
37  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
38  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
39  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
40  * POSSIBILITY OF SUCH DAMAGE.
41  */
42 
43 /*
44  * Printer Class spec: http://www.usb.org/developers/data/devclass/usbprint109.PDF
45  * Printer Class spec: http://www.usb.org/developers/devclass_docs/usbprint11.pdf
46  */
47 
48 #include <sys/stdint.h>
49 #include <sys/stddef.h>
50 #include <sys/param.h>
51 #include <sys/queue.h>
52 #include <sys/types.h>
53 #include <sys/systm.h>
54 #include <sys/kernel.h>
55 #include <sys/bus.h>
56 #include <sys/linker_set.h>
57 #include <sys/module.h>
58 #include <sys/lock.h>
59 #include <sys/mutex.h>
60 #include <sys/condvar.h>
61 #include <sys/sysctl.h>
62 #include <sys/sx.h>
63 #include <sys/unistd.h>
64 #include <sys/callout.h>
65 #include <sys/malloc.h>
66 #include <sys/priv.h>
67 #include <sys/syslog.h>
68 #include <sys/selinfo.h>
69 #include <sys/conf.h>
70 #include <sys/fcntl.h>
71 
72 #include <dev/usb/usb.h>
73 #include <dev/usb/usbdi.h>
74 #include <dev/usb/usbdi_util.h>
75 #include <dev/usb/usbhid.h>
76 #include "usbdevs.h"
77 
78 #define	USB_DEBUG_VAR ulpt_debug
79 #include <dev/usb/usb_debug.h>
80 #include <dev/usb/usb_process.h>
81 
82 #if USB_DEBUG
83 static int ulpt_debug = 0;
84 
85 SYSCTL_NODE(_hw_usb, OID_AUTO, ulpt, CTLFLAG_RW, 0, "USB ulpt");
86 SYSCTL_INT(_hw_usb_ulpt, OID_AUTO, debug, CTLFLAG_RW,
87     &ulpt_debug, 0, "Debug level");
88 #endif
89 
90 #define	ULPT_BSIZE		(1<<15)	/* bytes */
91 #define	ULPT_IFQ_MAXLEN         2	/* units */
92 
93 #define	UR_GET_DEVICE_ID        0x00
94 #define	UR_GET_PORT_STATUS      0x01
95 #define	UR_SOFT_RESET           0x02
96 
97 #define	LPS_NERR		0x08	/* printer no error */
98 #define	LPS_SELECT		0x10	/* printer selected */
99 #define	LPS_NOPAPER		0x20	/* printer out of paper */
100 #define	LPS_INVERT      (LPS_SELECT|LPS_NERR)
101 #define	LPS_MASK        (LPS_SELECT|LPS_NERR|LPS_NOPAPER)
102 
103 enum {
104 	ULPT_BULK_DT_WR,
105 	ULPT_BULK_DT_RD,
106 	ULPT_INTR_DT_RD,
107 	ULPT_N_TRANSFER,
108 };
109 
110 struct ulpt_softc {
111 	struct usb_fifo_sc sc_fifo;
112 	struct usb_fifo_sc sc_fifo_noreset;
113 	struct mtx sc_mtx;
114 	struct usb_callout sc_watchdog;
115 
116 	device_t sc_dev;
117 	struct usb_device *sc_udev;
118 	struct usb_fifo *sc_fifo_open[2];
119 	struct usb_xfer *sc_xfer[ULPT_N_TRANSFER];
120 
121 	int	sc_fflags;		/* current open flags, FREAD and
122 					 * FWRITE */
123 	uint8_t	sc_iface_no;
124 	uint8_t	sc_last_status;
125 	uint8_t	sc_zlps;		/* number of consequtive zero length
126 					 * packets received */
127 };
128 
129 /* prototypes */
130 
131 static device_probe_t ulpt_probe;
132 static device_attach_t ulpt_attach;
133 static device_detach_t ulpt_detach;
134 
135 static usb_callback_t ulpt_write_callback;
136 static usb_callback_t ulpt_read_callback;
137 static usb_callback_t ulpt_status_callback;
138 
139 static void	ulpt_reset(struct ulpt_softc *);
140 static void	ulpt_watchdog(void *);
141 
142 static usb_fifo_close_t ulpt_close;
143 static usb_fifo_cmd_t ulpt_start_read;
144 static usb_fifo_cmd_t ulpt_start_write;
145 static usb_fifo_cmd_t ulpt_stop_read;
146 static usb_fifo_cmd_t ulpt_stop_write;
147 static usb_fifo_ioctl_t ulpt_ioctl;
148 static usb_fifo_open_t ulpt_open;
149 static usb_fifo_open_t unlpt_open;
150 
151 static struct usb_fifo_methods ulpt_fifo_methods = {
152 	.f_close = &ulpt_close,
153 	.f_ioctl = &ulpt_ioctl,
154 	.f_open = &ulpt_open,
155 	.f_start_read = &ulpt_start_read,
156 	.f_start_write = &ulpt_start_write,
157 	.f_stop_read = &ulpt_stop_read,
158 	.f_stop_write = &ulpt_stop_write,
159 	.basename[0] = "ulpt",
160 };
161 
162 static struct usb_fifo_methods unlpt_fifo_methods = {
163 	.f_close = &ulpt_close,
164 	.f_ioctl = &ulpt_ioctl,
165 	.f_open = &unlpt_open,
166 	.f_start_read = &ulpt_start_read,
167 	.f_start_write = &ulpt_start_write,
168 	.f_stop_read = &ulpt_stop_read,
169 	.f_stop_write = &ulpt_stop_write,
170 	.basename[0] = "unlpt",
171 };
172 
173 static void
174 ulpt_reset(struct ulpt_softc *sc)
175 {
176 	struct usb_device_request req;
177 
178 	DPRINTFN(2, "\n");
179 
180 	req.bRequest = UR_SOFT_RESET;
181 	USETW(req.wValue, 0);
182 	USETW(req.wIndex, sc->sc_iface_no);
183 	USETW(req.wLength, 0);
184 
185 	/*
186 	 * There was a mistake in the USB printer 1.0 spec that gave the
187 	 * request type as UT_WRITE_CLASS_OTHER; it should have been
188 	 * UT_WRITE_CLASS_INTERFACE.  Many printers use the old one,
189 	 * so we try both.
190 	 */
191 
192 	mtx_lock(&sc->sc_mtx);
193 	req.bmRequestType = UT_WRITE_CLASS_OTHER;
194 	if (usbd_do_request_flags(sc->sc_udev, &sc->sc_mtx,
195 	    &req, NULL, 0, NULL, 2 * USB_MS_HZ)) {	/* 1.0 */
196 		req.bmRequestType = UT_WRITE_CLASS_INTERFACE;
197 		if (usbd_do_request_flags(sc->sc_udev, &sc->sc_mtx,
198 		    &req, NULL, 0, NULL, 2 * USB_MS_HZ)) {	/* 1.1 */
199 			/* ignore error */
200 		}
201 	}
202 	mtx_unlock(&sc->sc_mtx);
203 }
204 
205 static void
206 ulpt_write_callback(struct usb_xfer *xfer, usb_error_t error)
207 {
208 	struct ulpt_softc *sc = usbd_xfer_softc(xfer);
209 	struct usb_fifo *f = sc->sc_fifo_open[USB_FIFO_TX];
210 	struct usb_page_cache *pc;
211 	int actlen, max;
212 
213 	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
214 
215 	if (f == NULL) {
216 		/* should not happen */
217 		DPRINTF("no FIFO\n");
218 		return;
219 	}
220 	DPRINTF("state=0x%x actlen=%d\n", USB_GET_STATE(xfer), actlen);
221 
222 	switch (USB_GET_STATE(xfer)) {
223 	case USB_ST_TRANSFERRED:
224 	case USB_ST_SETUP:
225 tr_setup:
226 		pc = usbd_xfer_get_frame(xfer, 0);
227 		max = usbd_xfer_max_len(xfer);
228 		if (usb_fifo_get_data(f, pc, 0, max, &actlen, 0)) {
229 			usbd_xfer_set_frame_len(xfer, 0, actlen);
230 			usbd_transfer_submit(xfer);
231 		}
232 		break;
233 
234 	default:			/* Error */
235 		if (error != USB_ERR_CANCELLED) {
236 			/* try to clear stall first */
237 			usbd_xfer_set_stall(xfer);
238 			goto tr_setup;
239 		}
240 		break;
241 	}
242 }
243 
244 static void
245 ulpt_read_callback(struct usb_xfer *xfer, usb_error_t error)
246 {
247 	struct ulpt_softc *sc = usbd_xfer_softc(xfer);
248 	struct usb_fifo *f = sc->sc_fifo_open[USB_FIFO_RX];
249 	struct usb_page_cache *pc;
250 	int actlen;
251 
252 	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
253 
254 	if (f == NULL) {
255 		/* should not happen */
256 		DPRINTF("no FIFO\n");
257 		return;
258 	}
259 	DPRINTF("state=0x%x\n", USB_GET_STATE(xfer));
260 
261 	switch (USB_GET_STATE(xfer)) {
262 	case USB_ST_TRANSFERRED:
263 
264 		if (actlen == 0) {
265 
266 			if (sc->sc_zlps == 4) {
267 				/* enable BULK throttle */
268 				usbd_xfer_set_interval(xfer, 500); /* ms */
269 			} else {
270 				sc->sc_zlps++;
271 			}
272 		} else {
273 			/* disable BULK throttle */
274 
275 			usbd_xfer_set_interval(xfer, 0);
276 			sc->sc_zlps = 0;
277 		}
278 
279 		pc = usbd_xfer_get_frame(xfer, 0);
280 		usb_fifo_put_data(f, pc, 0, actlen, 1);
281 
282 	case USB_ST_SETUP:
283 tr_setup:
284 		if (usb_fifo_put_bytes_max(f) != 0) {
285 			usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
286 			usbd_transfer_submit(xfer);
287 		}
288 		break;
289 
290 	default:			/* Error */
291 		/* disable BULK throttle */
292 		usbd_xfer_set_interval(xfer, 0);
293 		sc->sc_zlps = 0;
294 
295 		if (error != USB_ERR_CANCELLED) {
296 			/* try to clear stall first */
297 			usbd_xfer_set_stall(xfer);
298 			goto tr_setup;
299 		}
300 		break;
301 	}
302 }
303 
304 static void
305 ulpt_status_callback(struct usb_xfer *xfer, usb_error_t error)
306 {
307 	struct ulpt_softc *sc = usbd_xfer_softc(xfer);
308 	struct usb_device_request req;
309 	struct usb_page_cache *pc;
310 	uint8_t cur_status;
311 	uint8_t new_status;
312 
313 	switch (USB_GET_STATE(xfer)) {
314 	case USB_ST_TRANSFERRED:
315 
316 		pc = usbd_xfer_get_frame(xfer, 1);
317 		usbd_copy_out(pc, 0, &cur_status, 1);
318 
319 		cur_status = (cur_status ^ LPS_INVERT) & LPS_MASK;
320 		new_status = cur_status & ~sc->sc_last_status;
321 		sc->sc_last_status = cur_status;
322 
323 		if (new_status & LPS_SELECT)
324 			log(LOG_NOTICE, "%s: offline\n",
325 			    device_get_nameunit(sc->sc_dev));
326 		else if (new_status & LPS_NOPAPER)
327 			log(LOG_NOTICE, "%s: out of paper\n",
328 			    device_get_nameunit(sc->sc_dev));
329 		else if (new_status & LPS_NERR)
330 			log(LOG_NOTICE, "%s: output error\n",
331 			    device_get_nameunit(sc->sc_dev));
332 		break;
333 
334 	case USB_ST_SETUP:
335 		req.bmRequestType = UT_READ_CLASS_INTERFACE;
336 		req.bRequest = UR_GET_PORT_STATUS;
337 		USETW(req.wValue, 0);
338 		req.wIndex[0] = sc->sc_iface_no;
339 		req.wIndex[1] = 0;
340 		USETW(req.wLength, 1);
341 
342 		pc = usbd_xfer_get_frame(xfer, 0);
343 		usbd_copy_in(pc, 0, &req, sizeof(req));
344 
345 		usbd_xfer_set_frame_len(xfer, 0, sizeof(req));
346 		usbd_xfer_set_frame_len(xfer, 1, 1);
347 		usbd_xfer_set_frames(xfer, 2);
348 		usbd_transfer_submit(xfer);
349 		break;
350 
351 	default:			/* Error */
352 		DPRINTF("error=%s\n", usbd_errstr(error));
353 		if (error != USB_ERR_CANCELLED) {
354 			/* wait for next watchdog timeout */
355 		}
356 		break;
357 	}
358 }
359 
360 static const struct usb_config ulpt_config[ULPT_N_TRANSFER] = {
361 	[ULPT_BULK_DT_WR] = {
362 		.type = UE_BULK,
363 		.endpoint = UE_ADDR_ANY,
364 		.direction = UE_DIR_OUT,
365 		.bufsize = ULPT_BSIZE,
366 		.flags = {.pipe_bof = 1,.proxy_buffer = 1},
367 		.callback = &ulpt_write_callback,
368 	},
369 
370 	[ULPT_BULK_DT_RD] = {
371 		.type = UE_BULK,
372 		.endpoint = UE_ADDR_ANY,
373 		.direction = UE_DIR_IN,
374 		.bufsize = ULPT_BSIZE,
375 		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,.proxy_buffer = 1},
376 		.callback = &ulpt_read_callback,
377 	},
378 
379 	[ULPT_INTR_DT_RD] = {
380 		.type = UE_CONTROL,
381 		.endpoint = 0x00,	/* Control pipe */
382 		.direction = UE_DIR_ANY,
383 		.bufsize = sizeof(struct usb_device_request) + 1,
384 		.callback = &ulpt_status_callback,
385 		.timeout = 1000,	/* 1 second */
386 	},
387 };
388 
389 static void
390 ulpt_start_read(struct usb_fifo *fifo)
391 {
392 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
393 
394 	usbd_transfer_start(sc->sc_xfer[ULPT_BULK_DT_RD]);
395 }
396 
397 static void
398 ulpt_stop_read(struct usb_fifo *fifo)
399 {
400 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
401 
402 	usbd_transfer_stop(sc->sc_xfer[ULPT_BULK_DT_RD]);
403 }
404 
405 static void
406 ulpt_start_write(struct usb_fifo *fifo)
407 {
408 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
409 
410 	usbd_transfer_start(sc->sc_xfer[ULPT_BULK_DT_WR]);
411 }
412 
413 static void
414 ulpt_stop_write(struct usb_fifo *fifo)
415 {
416 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
417 
418 	usbd_transfer_stop(sc->sc_xfer[ULPT_BULK_DT_WR]);
419 }
420 
421 static int
422 ulpt_open(struct usb_fifo *fifo, int fflags)
423 {
424 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
425 
426 	/* we assume that open is a serial process */
427 
428 	if (sc->sc_fflags == 0) {
429 
430 		/* reset USB paralell port */
431 
432 		ulpt_reset(sc);
433 	}
434 	return (unlpt_open(fifo, fflags));
435 }
436 
437 static int
438 unlpt_open(struct usb_fifo *fifo, int fflags)
439 {
440 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
441 
442 	if (sc->sc_fflags & fflags) {
443 		return (EBUSY);
444 	}
445 	if (fflags & FREAD) {
446 		/* clear stall first */
447 		mtx_lock(&sc->sc_mtx);
448 		usbd_xfer_set_stall(sc->sc_xfer[ULPT_BULK_DT_RD]);
449 		mtx_unlock(&sc->sc_mtx);
450 		if (usb_fifo_alloc_buffer(fifo,
451 		    usbd_xfer_max_len(sc->sc_xfer[ULPT_BULK_DT_RD]),
452 		    ULPT_IFQ_MAXLEN)) {
453 			return (ENOMEM);
454 		}
455 		/* set which FIFO is opened */
456 		sc->sc_fifo_open[USB_FIFO_RX] = fifo;
457 	}
458 	if (fflags & FWRITE) {
459 		/* clear stall first */
460 		mtx_lock(&sc->sc_mtx);
461 		usbd_xfer_set_stall(sc->sc_xfer[ULPT_BULK_DT_WR]);
462 		mtx_unlock(&sc->sc_mtx);
463 		if (usb_fifo_alloc_buffer(fifo,
464 		    usbd_xfer_max_len(sc->sc_xfer[ULPT_BULK_DT_WR]),
465 		    ULPT_IFQ_MAXLEN)) {
466 			return (ENOMEM);
467 		}
468 		/* set which FIFO is opened */
469 		sc->sc_fifo_open[USB_FIFO_TX] = fifo;
470 	}
471 	sc->sc_fflags |= fflags & (FREAD | FWRITE);
472 	return (0);
473 }
474 
475 static void
476 ulpt_close(struct usb_fifo *fifo, int fflags)
477 {
478 	struct ulpt_softc *sc = usb_fifo_softc(fifo);
479 
480 	sc->sc_fflags &= ~(fflags & (FREAD | FWRITE));
481 
482 	if (fflags & (FREAD | FWRITE)) {
483 		usb_fifo_free_buffer(fifo);
484 	}
485 }
486 
487 static int
488 ulpt_ioctl(struct usb_fifo *fifo, u_long cmd, void *data,
489     int fflags)
490 {
491 	return (ENODEV);
492 }
493 
494 static int
495 ulpt_probe(device_t dev)
496 {
497 	struct usb_attach_arg *uaa = device_get_ivars(dev);
498 
499 	DPRINTFN(11, "\n");
500 
501 	if (uaa->usb_mode != USB_MODE_HOST) {
502 		return (ENXIO);
503 	}
504 	if ((uaa->info.bInterfaceClass == UICLASS_PRINTER) &&
505 	    (uaa->info.bInterfaceSubClass == UISUBCLASS_PRINTER) &&
506 	    ((uaa->info.bInterfaceProtocol == UIPROTO_PRINTER_UNI) ||
507 	    (uaa->info.bInterfaceProtocol == UIPROTO_PRINTER_BI) ||
508 	    (uaa->info.bInterfaceProtocol == UIPROTO_PRINTER_1284))) {
509 		return (0);
510 	}
511 	return (ENXIO);
512 }
513 
514 static int
515 ulpt_attach(device_t dev)
516 {
517 	struct usb_attach_arg *uaa = device_get_ivars(dev);
518 	struct ulpt_softc *sc = device_get_softc(dev);
519 	struct usb_interface_descriptor *id;
520 	int unit = device_get_unit(dev);
521 	int error;
522 	uint8_t iface_index = uaa->info.bIfaceIndex;
523 	uint8_t alt_index;
524 
525 	DPRINTFN(11, "sc=%p\n", sc);
526 
527 	sc->sc_dev = dev;
528 	sc->sc_udev = uaa->device;
529 
530 	device_set_usb_desc(dev);
531 
532 	mtx_init(&sc->sc_mtx, "ulpt lock", NULL, MTX_DEF | MTX_RECURSE);
533 
534 	usb_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);
535 
536 	/* search through all the descriptors looking for bidir mode */
537 
538 	id = usbd_get_interface_descriptor(uaa->iface);
539 	alt_index = 0 - 1;
540 	while (1) {
541 		if (id == NULL) {
542 			break;
543 		}
544 		if ((id->bDescriptorType == UDESC_INTERFACE) &&
545 		    (id->bLength >= sizeof(*id))) {
546 			if (id->bInterfaceNumber != uaa->info.bIfaceNum) {
547 				break;
548 			} else {
549 				alt_index++;
550 				if ((id->bInterfaceClass == UICLASS_PRINTER) &&
551 				    (id->bInterfaceSubClass == UISUBCLASS_PRINTER) &&
552 				    (id->bInterfaceProtocol == UIPROTO_PRINTER_BI)) {
553 					goto found;
554 				}
555 			}
556 		}
557 		id = (void *)usb_desc_foreach(
558 		    usbd_get_config_descriptor(uaa->device), (void *)id);
559 	}
560 	goto detach;
561 
562 found:
563 
564 	DPRINTF("setting alternate "
565 	    "config number: %d\n", alt_index);
566 
567 	if (alt_index) {
568 
569 		error = usbd_set_alt_interface_index
570 		    (uaa->device, iface_index, alt_index);
571 
572 		if (error) {
573 			DPRINTF("could not set alternate "
574 			    "config, error=%s\n", usbd_errstr(error));
575 			goto detach;
576 		}
577 	}
578 	sc->sc_iface_no = id->bInterfaceNumber;
579 
580 	error = usbd_transfer_setup(uaa->device, &iface_index,
581 	    sc->sc_xfer, ulpt_config, ULPT_N_TRANSFER,
582 	    sc, &sc->sc_mtx);
583 	if (error) {
584 		DPRINTF("error=%s\n", usbd_errstr(error));
585 		goto detach;
586 	}
587 	device_printf(sc->sc_dev, "using bi-directional mode\n");
588 
589 #if 0
590 /*
591  * This code is disabled because for some mysterious reason it causes
592  * printing not to work.  But only sometimes, and mostly with
593  * UHCI and less often with OHCI.  *sigh*
594  */
595 	{
596 		struct usb_config_descriptor *cd = usbd_get_config_descriptor(dev);
597 		struct usb_device_request req;
598 		int len, alen;
599 
600 		req.bmRequestType = UT_READ_CLASS_INTERFACE;
601 		req.bRequest = UR_GET_DEVICE_ID;
602 		USETW(req.wValue, cd->bConfigurationValue);
603 		USETW2(req.wIndex, id->bInterfaceNumber, id->bAlternateSetting);
604 		USETW(req.wLength, sizeof devinfo - 1);
605 		error = usbd_do_request_flags(dev, &req, devinfo, USB_SHORT_XFER_OK,
606 		    &alen, USB_DEFAULT_TIMEOUT);
607 		if (error) {
608 			device_printf(sc->sc_dev, "cannot get device id\n");
609 		} else if (alen <= 2) {
610 			device_printf(sc->sc_dev, "empty device id, no "
611 			    "printer connected?\n");
612 		} else {
613 			/* devinfo now contains an IEEE-1284 device ID */
614 			len = ((devinfo[0] & 0xff) << 8) | (devinfo[1] & 0xff);
615 			if (len > sizeof devinfo - 3)
616 				len = sizeof devinfo - 3;
617 			devinfo[len] = 0;
618 			printf("%s: device id <", device_get_nameunit(sc->sc_dev));
619 			ieee1284_print_id(devinfo + 2);
620 			printf(">\n");
621 		}
622 	}
623 #endif
624 
625 	error = usb_fifo_attach(uaa->device, sc, &sc->sc_mtx,
626 	    &ulpt_fifo_methods, &sc->sc_fifo,
627 	    unit, 0 - 1, uaa->info.bIfaceIndex,
628 	    UID_ROOT, GID_OPERATOR, 0644);
629 	if (error) {
630 		goto detach;
631 	}
632 	error = usb_fifo_attach(uaa->device, sc, &sc->sc_mtx,
633 	    &unlpt_fifo_methods, &sc->sc_fifo_noreset,
634 	    unit, 0 - 1, uaa->info.bIfaceIndex,
635 	    UID_ROOT, GID_OPERATOR, 0644);
636 	if (error) {
637 		goto detach;
638 	}
639 	/* start reading of status */
640 
641 	mtx_lock(&sc->sc_mtx);
642 	ulpt_watchdog(sc);
643 	mtx_unlock(&sc->sc_mtx);
644 	return (0);
645 
646 detach:
647 	ulpt_detach(dev);
648 	return (ENOMEM);
649 }
650 
651 static int
652 ulpt_detach(device_t dev)
653 {
654 	struct ulpt_softc *sc = device_get_softc(dev);
655 
656 	DPRINTF("sc=%p\n", sc);
657 
658 	usb_fifo_detach(&sc->sc_fifo);
659 	usb_fifo_detach(&sc->sc_fifo_noreset);
660 
661 	mtx_lock(&sc->sc_mtx);
662 	usb_callout_stop(&sc->sc_watchdog);
663 	mtx_unlock(&sc->sc_mtx);
664 
665 	usbd_transfer_unsetup(sc->sc_xfer, ULPT_N_TRANSFER);
666 	usb_callout_drain(&sc->sc_watchdog);
667 	mtx_destroy(&sc->sc_mtx);
668 
669 	return (0);
670 }
671 
672 #if 0
673 /* XXX This does not belong here. */
674 
675 /*
676  * Compare two strings until the second ends.
677  */
678 
679 static uint8_t
680 ieee1284_compare(const char *a, const char *b)
681 {
682 	while (1) {
683 
684 		if (*b == 0) {
685 			break;
686 		}
687 		if (*a != *b) {
688 			return 1;
689 		}
690 		b++;
691 		a++;
692 	}
693 	return 0;
694 }
695 
696 /*
697  * Print select parts of an IEEE 1284 device ID.
698  */
699 void
700 ieee1284_print_id(char *str)
701 {
702 	char *p, *q;
703 
704 	for (p = str - 1; p; p = strchr(p, ';')) {
705 		p++;			/* skip ';' */
706 		if (ieee1284_compare(p, "MFG:") == 0 ||
707 		    ieee1284_compare(p, "MANUFACTURER:") == 0 ||
708 		    ieee1284_compare(p, "MDL:") == 0 ||
709 		    ieee1284_compare(p, "MODEL:") == 0) {
710 			q = strchr(p, ';');
711 			if (q)
712 				printf("%.*s", (int)(q - p + 1), p);
713 		}
714 	}
715 }
716 
717 #endif
718 
719 static void
720 ulpt_watchdog(void *arg)
721 {
722 	struct ulpt_softc *sc = arg;
723 
724 	mtx_assert(&sc->sc_mtx, MA_OWNED);
725 
726 	/*
727 	 * Only read status while the device is not opened, due to
728 	 * possible hardware or firmware bug in some printers.
729 	 */
730 	if (sc->sc_fflags == 0)
731 		usbd_transfer_start(sc->sc_xfer[ULPT_INTR_DT_RD]);
732 
733 	usb_callout_reset(&sc->sc_watchdog,
734 	    hz, &ulpt_watchdog, sc);
735 }
736 
737 static devclass_t ulpt_devclass;
738 
739 static device_method_t ulpt_methods[] = {
740 	DEVMETHOD(device_probe, ulpt_probe),
741 	DEVMETHOD(device_attach, ulpt_attach),
742 	DEVMETHOD(device_detach, ulpt_detach),
743 	{0, 0}
744 };
745 
746 static driver_t ulpt_driver = {
747 	.name = "ulpt",
748 	.methods = ulpt_methods,
749 	.size = sizeof(struct ulpt_softc),
750 };
751 
752 DRIVER_MODULE(ulpt, uhub, ulpt_driver, ulpt_devclass, NULL, 0);
753 MODULE_DEPEND(ulpt, usb, 1, 1, 1);
754 MODULE_DEPEND(ulpt, ucom, 1, 1, 1);
755