xref: /linux/drivers/usb/class/usblp.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 /*
2  * usblp.c
3  *
4  * Copyright (c) 1999 Michael Gee	<michael@linuxspecific.com>
5  * Copyright (c) 1999 Pavel Machek	<pavel@ucw.cz>
6  * Copyright (c) 2000 Randy Dunlap	<rdunlap@xenotime.net>
7  * Copyright (c) 2000 Vojtech Pavlik	<vojtech@suse.cz>
8  # Copyright (c) 2001 Pete Zaitcev	<zaitcev@redhat.com>
9  # Copyright (c) 2001 David Paschal	<paschal@rcsis.com>
10  * Copyright (c) 2006 Oliver Neukum	<oliver@neukum.name>
11  *
12  * USB Printer Device Class driver for USB printers and printer cables
13  *
14  * Sponsored by SuSE
15  *
16  * ChangeLog:
17  *	v0.1 - thorough cleaning, URBification, almost a rewrite
18  *	v0.2 - some more cleanups
19  *	v0.3 - cleaner again, waitqueue fixes
20  *	v0.4 - fixes in unidirectional mode
21  *	v0.5 - add DEVICE_ID string support
22  *	v0.6 - never time out
23  *	v0.7 - fixed bulk-IN read and poll (David Paschal)
24  *	v0.8 - add devfs support
25  *	v0.9 - fix unplug-while-open paths
26  *	v0.10- remove sleep_on, fix error on oom (oliver@neukum.org)
27  *	v0.11 - add proto_bias option (Pete Zaitcev)
28  *	v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
29  *	v0.13 - alloc space for statusbuf (<status> not on stack);
30  *		use usb_alloc_coherent() for read buf & write buf;
31  *      none  - Maintained in Linux kernel after v0.13
32  */
33 
34 /*
35  * This program is free software; you can redistribute it and/or modify
36  * it under the terms of the GNU General Public License as published by
37  * the Free Software Foundation; either version 2 of the License, or
38  * (at your option) any later version.
39  *
40  * This program is distributed in the hope that it will be useful,
41  * but WITHOUT ANY WARRANTY; without even the implied warranty of
42  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
43  * GNU General Public License for more details.
44  *
45  * You should have received a copy of the GNU General Public License
46  * along with this program; if not, write to the Free Software
47  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
48  */
49 
50 #include <linux/module.h>
51 #include <linux/kernel.h>
52 #include <linux/sched.h>
53 #include <linux/signal.h>
54 #include <linux/poll.h>
55 #include <linux/slab.h>
56 #include <linux/lp.h>
57 #include <linux/mutex.h>
58 #undef DEBUG
59 #include <linux/usb.h>
60 #include <linux/ratelimit.h>
61 
62 /*
63  * Version Information
64  */
65 #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
66 #define DRIVER_DESC "USB Printer Device Class driver"
67 
68 #define USBLP_BUF_SIZE		8192
69 #define USBLP_BUF_SIZE_IN	1024
70 #define USBLP_DEVICE_ID_SIZE	1024
71 
72 /* ioctls: */
73 #define IOCNR_GET_DEVICE_ID		1
74 #define IOCNR_GET_PROTOCOLS		2
75 #define IOCNR_SET_PROTOCOL		3
76 #define IOCNR_HP_SET_CHANNEL		4
77 #define IOCNR_GET_BUS_ADDRESS		5
78 #define IOCNR_GET_VID_PID		6
79 #define IOCNR_SOFT_RESET		7
80 /* Get device_id string: */
81 #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
82 /* The following ioctls were added for http://hpoj.sourceforge.net: */
83 /* Get two-int array:
84  * [0]=current protocol (1=7/1/1, 2=7/1/2, 3=7/1/3),
85  * [1]=supported protocol mask (mask&(1<<n)!=0 means 7/1/n supported): */
86 #define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
87 /* Set protocol (arg: 1=7/1/1, 2=7/1/2, 3=7/1/3): */
88 #define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
89 /* Set channel number (HP Vendor-specific command): */
90 #define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
91 /* Get two-int array: [0]=bus number, [1]=device address: */
92 #define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
93 /* Get two-int array: [0]=vendor ID, [1]=product ID: */
94 #define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
95 /* Perform class specific soft reset */
96 #define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
97 
98 /*
99  * A DEVICE_ID string may include the printer's serial number.
100  * It should end with a semi-colon (';').
101  * An example from an HP 970C DeskJet printer is (this is one long string,
102  * with the serial number changed):
103 MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:Hewlett-Packard DeskJet 970C;SERN:US970CSEPROF;VSTATUS:$HB0$NC0,ff,DN,IDLE,CUT,K1,C0,DP,NR,KP000,CP027;VP:0800,FL,B0;VJ:                    ;
104  */
105 
106 /*
107  * USB Printer Requests
108  */
109 
110 #define USBLP_REQ_GET_ID			0x00
111 #define USBLP_REQ_GET_STATUS			0x01
112 #define USBLP_REQ_RESET				0x02
113 #define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST	0x00	/* HP Vendor-specific */
114 
115 #define USBLP_MINORS		16
116 #define USBLP_MINOR_BASE	0
117 
118 #define USBLP_CTL_TIMEOUT	5000			/* 5 seconds */
119 
120 #define USBLP_FIRST_PROTOCOL	1
121 #define USBLP_LAST_PROTOCOL	3
122 #define USBLP_MAX_PROTOCOLS	(USBLP_LAST_PROTOCOL+1)
123 
124 /*
125  * some arbitrary status buffer size;
126  * need a status buffer that is allocated via kmalloc(), not on stack
127  */
128 #define STATUS_BUF_SIZE		8
129 
130 /*
131  * Locks down the locking order:
132  * ->wmut locks wstatus.
133  * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
134  * [rw]status. We only touch status when we know the side idle.
135  * ->lock locks what interrupt accesses.
136  */
137 struct usblp {
138 	struct usb_device	*dev;			/* USB device */
139 	struct mutex		wmut;
140 	struct mutex		mut;
141 	spinlock_t		lock;		/* locks rcomplete, wcomplete */
142 	char			*readbuf;		/* read transfer_buffer */
143 	char			*statusbuf;		/* status transfer_buffer */
144 	struct usb_anchor	urbs;
145 	wait_queue_head_t	rwait, wwait;
146 	int			readcount;		/* Counter for reads */
147 	int			ifnum;			/* Interface number */
148 	struct usb_interface	*intf;			/* The interface */
149 	/* Alternate-setting numbers and endpoints for each protocol
150 	 * (7/1/{index=1,2,3}) that the device supports: */
151 	struct {
152 		int				alt_setting;
153 		struct usb_endpoint_descriptor	*epwrite;
154 		struct usb_endpoint_descriptor	*epread;
155 	}			protocol[USBLP_MAX_PROTOCOLS];
156 	int			current_protocol;
157 	int			minor;			/* minor number of device */
158 	int			wcomplete, rcomplete;
159 	int			wstatus;	/* bytes written or error */
160 	int			rstatus;	/* bytes ready or error */
161 	unsigned int		quirks;			/* quirks flags */
162 	unsigned int		flags;			/* mode flags */
163 	unsigned char		used;			/* True if open */
164 	unsigned char		present;		/* True if not disconnected */
165 	unsigned char		bidir;			/* interface is bidirectional */
166 	unsigned char		no_paper;		/* Paper Out happened */
167 	unsigned char		*device_id_string;	/* IEEE 1284 DEVICE ID string (ptr) */
168 							/* first 2 bytes are (big-endian) length */
169 };
170 
171 #ifdef DEBUG
172 static void usblp_dump(struct usblp *usblp)
173 {
174 	struct device *dev = &usblp->intf->dev;
175 	int p;
176 
177 	dev_dbg(dev, "usblp=0x%p\n", usblp);
178 	dev_dbg(dev, "dev=0x%p\n", usblp->dev);
179 	dev_dbg(dev, "present=%d\n", usblp->present);
180 	dev_dbg(dev, "readbuf=0x%p\n", usblp->readbuf);
181 	dev_dbg(dev, "readcount=%d\n", usblp->readcount);
182 	dev_dbg(dev, "ifnum=%d\n", usblp->ifnum);
183 	for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
184 		dev_dbg(dev, "protocol[%d].alt_setting=%d\n", p,
185 			usblp->protocol[p].alt_setting);
186 		dev_dbg(dev, "protocol[%d].epwrite=%p\n", p,
187 			usblp->protocol[p].epwrite);
188 		dev_dbg(dev, "protocol[%d].epread=%p\n", p,
189 			usblp->protocol[p].epread);
190 	}
191 	dev_dbg(dev, "current_protocol=%d\n", usblp->current_protocol);
192 	dev_dbg(dev, "minor=%d\n", usblp->minor);
193 	dev_dbg(dev, "wstatus=%d\n", usblp->wstatus);
194 	dev_dbg(dev, "rstatus=%d\n", usblp->rstatus);
195 	dev_dbg(dev, "quirks=%d\n", usblp->quirks);
196 	dev_dbg(dev, "used=%d\n", usblp->used);
197 	dev_dbg(dev, "bidir=%d\n", usblp->bidir);
198 	dev_dbg(dev, "device_id_string=\"%s\"\n",
199 		usblp->device_id_string ?
200 			usblp->device_id_string + 2 :
201 			(unsigned char *)"(null)");
202 }
203 #endif
204 
205 /* Quirks: various printer quirks are handled by this table & its flags. */
206 
207 struct quirk_printer_struct {
208 	__u16 vendorId;
209 	__u16 productId;
210 	unsigned int quirks;
211 };
212 
213 #define USBLP_QUIRK_BIDIR	0x1	/* reports bidir but requires unidirectional mode (no INs/reads) */
214 #define USBLP_QUIRK_USB_INIT	0x2	/* needs vendor USB init string */
215 #define USBLP_QUIRK_BAD_CLASS	0x4	/* descriptor uses vendor-specific Class or SubClass */
216 
217 static const struct quirk_printer_struct quirk_printers[] = {
218 	{ 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
219 	{ 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
220 	{ 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
221 	{ 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
222 	{ 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
223 	{ 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
224 	{ 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
225 	{ 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
226 	{ 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
227 	{ 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
228 	{ 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
229 	{ 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
230 	{ 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
231 	{ 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <kernel@zut.de> */
232 	{ 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
233 	{ 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
234 	{ 0, 0 }
235 };
236 
237 static int usblp_wwait(struct usblp *usblp, int nonblock);
238 static int usblp_wtest(struct usblp *usblp, int nonblock);
239 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
240 static int usblp_rtest(struct usblp *usblp, int nonblock);
241 static int usblp_submit_read(struct usblp *usblp);
242 static int usblp_select_alts(struct usblp *usblp);
243 static int usblp_set_protocol(struct usblp *usblp, int protocol);
244 static int usblp_cache_device_id_string(struct usblp *usblp);
245 
246 /* forward reference to make our lives easier */
247 static struct usb_driver usblp_driver;
248 static DEFINE_MUTEX(usblp_mutex);	/* locks the existence of usblp's */
249 
250 /*
251  * Functions for usblp control messages.
252  */
253 
254 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
255 {
256 	int retval;
257 	int index = usblp->ifnum;
258 
259 	/* High byte has the interface index.
260 	   Low byte has the alternate setting.
261 	 */
262 	if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS))
263 		index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
264 
265 	retval = usb_control_msg(usblp->dev,
266 		dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
267 		request, type | dir | recip, value, index, buf, len, USBLP_CTL_TIMEOUT);
268 	dev_dbg(&usblp->intf->dev,
269 		"usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d\n",
270 		request, !!dir, recip, value, index, len, retval);
271 	return retval < 0 ? retval : 0;
272 }
273 
274 #define usblp_read_status(usblp, status)\
275 	usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
276 #define usblp_get_id(usblp, config, id, maxlen)\
277 	usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
278 #define usblp_reset(usblp)\
279 	usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
280 
281 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
282 	usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
283 
284 /*
285  * See the description for usblp_select_alts() below for the usage
286  * explanation.  Look into your /proc/bus/usb/devices and dmesg in
287  * case of any trouble.
288  */
289 static int proto_bias = -1;
290 
291 /*
292  * URB callback.
293  */
294 
295 static void usblp_bulk_read(struct urb *urb)
296 {
297 	struct usblp *usblp = urb->context;
298 	int status = urb->status;
299 
300 	if (usblp->present && usblp->used) {
301 		if (status)
302 			printk(KERN_WARNING "usblp%d: "
303 			    "nonzero read bulk status received: %d\n",
304 			    usblp->minor, status);
305 	}
306 	spin_lock(&usblp->lock);
307 	if (status < 0)
308 		usblp->rstatus = status;
309 	else
310 		usblp->rstatus = urb->actual_length;
311 	usblp->rcomplete = 1;
312 	wake_up(&usblp->rwait);
313 	spin_unlock(&usblp->lock);
314 
315 	usb_free_urb(urb);
316 }
317 
318 static void usblp_bulk_write(struct urb *urb)
319 {
320 	struct usblp *usblp = urb->context;
321 	int status = urb->status;
322 
323 	if (usblp->present && usblp->used) {
324 		if (status)
325 			printk(KERN_WARNING "usblp%d: "
326 			    "nonzero write bulk status received: %d\n",
327 			    usblp->minor, status);
328 	}
329 	spin_lock(&usblp->lock);
330 	if (status < 0)
331 		usblp->wstatus = status;
332 	else
333 		usblp->wstatus = urb->actual_length;
334 	usblp->no_paper = 0;
335 	usblp->wcomplete = 1;
336 	wake_up(&usblp->wwait);
337 	spin_unlock(&usblp->lock);
338 
339 	usb_free_urb(urb);
340 }
341 
342 /*
343  * Get and print printer errors.
344  */
345 
346 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
347 
348 static int usblp_check_status(struct usblp *usblp, int err)
349 {
350 	unsigned char status, newerr = 0;
351 	int error;
352 
353 	mutex_lock(&usblp->mut);
354 	if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
355 		mutex_unlock(&usblp->mut);
356 		printk_ratelimited(KERN_ERR
357 				"usblp%d: error %d reading printer status\n",
358 				usblp->minor, error);
359 		return 0;
360 	}
361 	status = *usblp->statusbuf;
362 	mutex_unlock(&usblp->mut);
363 
364 	if (~status & LP_PERRORP)
365 		newerr = 3;
366 	if (status & LP_POUTPA)
367 		newerr = 1;
368 	if (~status & LP_PSELECD)
369 		newerr = 2;
370 
371 	if (newerr != err) {
372 		printk(KERN_INFO "usblp%d: %s\n",
373 		   usblp->minor, usblp_messages[newerr]);
374 	}
375 
376 	return newerr;
377 }
378 
379 static int handle_bidir(struct usblp *usblp)
380 {
381 	if (usblp->bidir && usblp->used) {
382 		if (usblp_submit_read(usblp) < 0)
383 			return -EIO;
384 	}
385 	return 0;
386 }
387 
388 /*
389  * File op functions.
390  */
391 
392 static int usblp_open(struct inode *inode, struct file *file)
393 {
394 	int minor = iminor(inode);
395 	struct usblp *usblp;
396 	struct usb_interface *intf;
397 	int retval;
398 
399 	if (minor < 0)
400 		return -ENODEV;
401 
402 	mutex_lock(&usblp_mutex);
403 
404 	retval = -ENODEV;
405 	intf = usb_find_interface(&usblp_driver, minor);
406 	if (!intf)
407 		goto out;
408 	usblp = usb_get_intfdata(intf);
409 	if (!usblp || !usblp->dev || !usblp->present)
410 		goto out;
411 
412 	retval = -EBUSY;
413 	if (usblp->used)
414 		goto out;
415 
416 	/*
417 	 * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
418 	 *  - We do not want persistent state which close(2) does not clear
419 	 *  - It is not used anyway, according to CUPS people
420 	 */
421 
422 	retval = usb_autopm_get_interface(intf);
423 	if (retval < 0)
424 		goto out;
425 	usblp->used = 1;
426 	file->private_data = usblp;
427 
428 	usblp->wcomplete = 1; /* we begin writeable */
429 	usblp->wstatus = 0;
430 	usblp->rcomplete = 0;
431 
432 	if (handle_bidir(usblp) < 0) {
433 		usb_autopm_put_interface(intf);
434 		usblp->used = 0;
435 		file->private_data = NULL;
436 		retval = -EIO;
437 	}
438 out:
439 	mutex_unlock(&usblp_mutex);
440 	return retval;
441 }
442 
443 static void usblp_cleanup(struct usblp *usblp)
444 {
445 	printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
446 
447 	kfree(usblp->readbuf);
448 	kfree(usblp->device_id_string);
449 	kfree(usblp->statusbuf);
450 	kfree(usblp);
451 }
452 
453 static void usblp_unlink_urbs(struct usblp *usblp)
454 {
455 	usb_kill_anchored_urbs(&usblp->urbs);
456 }
457 
458 static int usblp_release(struct inode *inode, struct file *file)
459 {
460 	struct usblp *usblp = file->private_data;
461 
462 	usblp->flags &= ~LP_ABORT;
463 
464 	mutex_lock(&usblp_mutex);
465 	usblp->used = 0;
466 	if (usblp->present) {
467 		usblp_unlink_urbs(usblp);
468 		usb_autopm_put_interface(usblp->intf);
469 	} else		/* finish cleanup from disconnect */
470 		usblp_cleanup(usblp);
471 	mutex_unlock(&usblp_mutex);
472 	return 0;
473 }
474 
475 /* No kernel lock - fine */
476 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
477 {
478 	int ret;
479 	unsigned long flags;
480 
481 	struct usblp *usblp = file->private_data;
482 	/* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
483 	poll_wait(file, &usblp->rwait, wait);
484 	poll_wait(file, &usblp->wwait, wait);
485 	spin_lock_irqsave(&usblp->lock, flags);
486 	ret = ((usblp->bidir && usblp->rcomplete) ? POLLIN  | POLLRDNORM : 0) |
487 	   ((usblp->no_paper || usblp->wcomplete) ? POLLOUT | POLLWRNORM : 0);
488 	spin_unlock_irqrestore(&usblp->lock, flags);
489 	return ret;
490 }
491 
492 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
493 {
494 	struct usblp *usblp = file->private_data;
495 	int length, err, i;
496 	unsigned char newChannel;
497 	int status;
498 	int twoints[2];
499 	int retval = 0;
500 
501 	mutex_lock(&usblp->mut);
502 	if (!usblp->present) {
503 		retval = -ENODEV;
504 		goto done;
505 	}
506 
507 	dev_dbg(&usblp->intf->dev,
508 		"usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)\n", cmd,
509 		_IOC_TYPE(cmd), _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
510 
511 	if (_IOC_TYPE(cmd) == 'P')	/* new-style ioctl number */
512 
513 		switch (_IOC_NR(cmd)) {
514 
515 		case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
516 			if (_IOC_DIR(cmd) != _IOC_READ) {
517 				retval = -EINVAL;
518 				goto done;
519 			}
520 
521 			length = usblp_cache_device_id_string(usblp);
522 			if (length < 0) {
523 				retval = length;
524 				goto done;
525 			}
526 			if (length > _IOC_SIZE(cmd))
527 				length = _IOC_SIZE(cmd); /* truncate */
528 
529 			if (copy_to_user((void __user *) arg,
530 					usblp->device_id_string,
531 					(unsigned long) length)) {
532 				retval = -EFAULT;
533 				goto done;
534 			}
535 
536 			break;
537 
538 		case IOCNR_GET_PROTOCOLS:
539 			if (_IOC_DIR(cmd) != _IOC_READ ||
540 			    _IOC_SIZE(cmd) < sizeof(twoints)) {
541 				retval = -EINVAL;
542 				goto done;
543 			}
544 
545 			twoints[0] = usblp->current_protocol;
546 			twoints[1] = 0;
547 			for (i = USBLP_FIRST_PROTOCOL;
548 			     i <= USBLP_LAST_PROTOCOL; i++) {
549 				if (usblp->protocol[i].alt_setting >= 0)
550 					twoints[1] |= (1<<i);
551 			}
552 
553 			if (copy_to_user((void __user *)arg,
554 					(unsigned char *)twoints,
555 					sizeof(twoints))) {
556 				retval = -EFAULT;
557 				goto done;
558 			}
559 
560 			break;
561 
562 		case IOCNR_SET_PROTOCOL:
563 			if (_IOC_DIR(cmd) != _IOC_WRITE) {
564 				retval = -EINVAL;
565 				goto done;
566 			}
567 
568 #ifdef DEBUG
569 			if (arg == -10) {
570 				usblp_dump(usblp);
571 				break;
572 			}
573 #endif
574 
575 			usblp_unlink_urbs(usblp);
576 			retval = usblp_set_protocol(usblp, arg);
577 			if (retval < 0) {
578 				usblp_set_protocol(usblp,
579 					usblp->current_protocol);
580 			}
581 			break;
582 
583 		case IOCNR_HP_SET_CHANNEL:
584 			if (_IOC_DIR(cmd) != _IOC_WRITE ||
585 			    le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
586 			    usblp->quirks & USBLP_QUIRK_BIDIR) {
587 				retval = -EINVAL;
588 				goto done;
589 			}
590 
591 			err = usblp_hp_channel_change_request(usblp,
592 				arg, &newChannel);
593 			if (err < 0) {
594 				dev_err(&usblp->dev->dev,
595 					"usblp%d: error = %d setting "
596 					"HP channel\n",
597 					usblp->minor, err);
598 				retval = -EIO;
599 				goto done;
600 			}
601 
602 			dev_dbg(&usblp->intf->dev,
603 				"usblp%d requested/got HP channel %ld/%d\n",
604 				usblp->minor, arg, newChannel);
605 			break;
606 
607 		case IOCNR_GET_BUS_ADDRESS:
608 			if (_IOC_DIR(cmd) != _IOC_READ ||
609 			    _IOC_SIZE(cmd) < sizeof(twoints)) {
610 				retval = -EINVAL;
611 				goto done;
612 			}
613 
614 			twoints[0] = usblp->dev->bus->busnum;
615 			twoints[1] = usblp->dev->devnum;
616 			if (copy_to_user((void __user *)arg,
617 					(unsigned char *)twoints,
618 					sizeof(twoints))) {
619 				retval = -EFAULT;
620 				goto done;
621 			}
622 
623 			dev_dbg(&usblp->intf->dev,
624 				"usblp%d is bus=%d, device=%d\n",
625 				usblp->minor, twoints[0], twoints[1]);
626 			break;
627 
628 		case IOCNR_GET_VID_PID:
629 			if (_IOC_DIR(cmd) != _IOC_READ ||
630 			    _IOC_SIZE(cmd) < sizeof(twoints)) {
631 				retval = -EINVAL;
632 				goto done;
633 			}
634 
635 			twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
636 			twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
637 			if (copy_to_user((void __user *)arg,
638 					(unsigned char *)twoints,
639 					sizeof(twoints))) {
640 				retval = -EFAULT;
641 				goto done;
642 			}
643 
644 			dev_dbg(&usblp->intf->dev,
645 				"usblp%d is VID=0x%4.4X, PID=0x%4.4X\n",
646 				usblp->minor, twoints[0], twoints[1]);
647 			break;
648 
649 		case IOCNR_SOFT_RESET:
650 			if (_IOC_DIR(cmd) != _IOC_NONE) {
651 				retval = -EINVAL;
652 				goto done;
653 			}
654 			retval = usblp_reset(usblp);
655 			break;
656 		default:
657 			retval = -ENOTTY;
658 		}
659 	else	/* old-style ioctl value */
660 		switch (cmd) {
661 
662 		case LPGETSTATUS:
663 			if ((retval = usblp_read_status(usblp, usblp->statusbuf))) {
664 				printk_ratelimited(KERN_ERR "usblp%d:"
665 					    "failed reading printer status (%d)\n",
666 					    usblp->minor, retval);
667 				retval = -EIO;
668 				goto done;
669 			}
670 			status = *usblp->statusbuf;
671 			if (copy_to_user((void __user *)arg, &status, sizeof(int)))
672 				retval = -EFAULT;
673 			break;
674 
675 		case LPABORT:
676 			if (arg)
677 				usblp->flags |= LP_ABORT;
678 			else
679 				usblp->flags &= ~LP_ABORT;
680 			break;
681 
682 		default:
683 			retval = -ENOTTY;
684 		}
685 
686 done:
687 	mutex_unlock(&usblp->mut);
688 	return retval;
689 }
690 
691 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
692 {
693 	struct urb *urb;
694 	char *writebuf;
695 
696 	if ((writebuf = kmalloc(transfer_length, GFP_KERNEL)) == NULL)
697 		return NULL;
698 	if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL) {
699 		kfree(writebuf);
700 		return NULL;
701 	}
702 
703 	usb_fill_bulk_urb(urb, usblp->dev,
704 		usb_sndbulkpipe(usblp->dev,
705 		 usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
706 		writebuf, transfer_length, usblp_bulk_write, usblp);
707 	urb->transfer_flags |= URB_FREE_BUFFER;
708 
709 	return urb;
710 }
711 
712 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
713 {
714 	struct usblp *usblp = file->private_data;
715 	struct urb *writeurb;
716 	int rv;
717 	int transfer_length;
718 	ssize_t writecount = 0;
719 
720 	if (mutex_lock_interruptible(&usblp->wmut)) {
721 		rv = -EINTR;
722 		goto raise_biglock;
723 	}
724 	if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
725 		goto raise_wait;
726 
727 	while (writecount < count) {
728 		/*
729 		 * Step 1: Submit next block.
730 		 */
731 		if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
732 			transfer_length = USBLP_BUF_SIZE;
733 
734 		rv = -ENOMEM;
735 		if ((writeurb = usblp_new_writeurb(usblp, transfer_length)) == NULL)
736 			goto raise_urb;
737 		usb_anchor_urb(writeurb, &usblp->urbs);
738 
739 		if (copy_from_user(writeurb->transfer_buffer,
740 				   buffer + writecount, transfer_length)) {
741 			rv = -EFAULT;
742 			goto raise_badaddr;
743 		}
744 
745 		spin_lock_irq(&usblp->lock);
746 		usblp->wcomplete = 0;
747 		spin_unlock_irq(&usblp->lock);
748 		if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
749 			usblp->wstatus = 0;
750 			spin_lock_irq(&usblp->lock);
751 			usblp->no_paper = 0;
752 			usblp->wcomplete = 1;
753 			wake_up(&usblp->wwait);
754 			spin_unlock_irq(&usblp->lock);
755 			if (rv != -ENOMEM)
756 				rv = -EIO;
757 			goto raise_submit;
758 		}
759 
760 		/*
761 		 * Step 2: Wait for transfer to end, collect results.
762 		 */
763 		rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
764 		if (rv < 0) {
765 			if (rv == -EAGAIN) {
766 				/* Presume that it's going to complete well. */
767 				writecount += transfer_length;
768 			}
769 			if (rv == -ENOSPC) {
770 				spin_lock_irq(&usblp->lock);
771 				usblp->no_paper = 1;	/* Mark for poll(2) */
772 				spin_unlock_irq(&usblp->lock);
773 				writecount += transfer_length;
774 			}
775 			/* Leave URB dangling, to be cleaned on close. */
776 			goto collect_error;
777 		}
778 
779 		if (usblp->wstatus < 0) {
780 			rv = -EIO;
781 			goto collect_error;
782 		}
783 		/*
784 		 * This is critical: it must be our URB, not other writer's.
785 		 * The wmut exists mainly to cover us here.
786 		 */
787 		writecount += usblp->wstatus;
788 	}
789 
790 	mutex_unlock(&usblp->wmut);
791 	return writecount;
792 
793 raise_submit:
794 raise_badaddr:
795 	usb_unanchor_urb(writeurb);
796 	usb_free_urb(writeurb);
797 raise_urb:
798 raise_wait:
799 collect_error:		/* Out of raise sequence */
800 	mutex_unlock(&usblp->wmut);
801 raise_biglock:
802 	return writecount ? writecount : rv;
803 }
804 
805 /*
806  * Notice that we fail to restart in a few cases: on EFAULT, on restart
807  * error, etc. This is the historical behaviour. In all such cases we return
808  * EIO, and applications loop in order to get the new read going.
809  */
810 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
811 {
812 	struct usblp *usblp = file->private_data;
813 	ssize_t count;
814 	ssize_t avail;
815 	int rv;
816 
817 	if (!usblp->bidir)
818 		return -EINVAL;
819 
820 	rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
821 	if (rv < 0)
822 		return rv;
823 
824 	if ((avail = usblp->rstatus) < 0) {
825 		printk(KERN_ERR "usblp%d: error %d reading from printer\n",
826 		    usblp->minor, (int)avail);
827 		usblp_submit_read(usblp);
828 		count = -EIO;
829 		goto done;
830 	}
831 
832 	count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
833 	if (count != 0 &&
834 	    copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
835 		count = -EFAULT;
836 		goto done;
837 	}
838 
839 	if ((usblp->readcount += count) == avail) {
840 		if (usblp_submit_read(usblp) < 0) {
841 			/* We don't want to leak USB return codes into errno. */
842 			if (count == 0)
843 				count = -EIO;
844 			goto done;
845 		}
846 	}
847 
848 done:
849 	mutex_unlock(&usblp->mut);
850 	return count;
851 }
852 
853 /*
854  * Wait for the write path to come idle.
855  * This is called under the ->wmut, so the idle path stays idle.
856  *
857  * Our write path has a peculiar property: it does not buffer like a tty,
858  * but waits for the write to succeed. This allows our ->release to bug out
859  * without waiting for writes to drain. But it obviously does not work
860  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
861  * select(2) or poll(2) to wait for the buffer to drain before closing.
862  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
863  */
864 static int usblp_wwait(struct usblp *usblp, int nonblock)
865 {
866 	DECLARE_WAITQUEUE(waita, current);
867 	int rc;
868 	int err = 0;
869 
870 	add_wait_queue(&usblp->wwait, &waita);
871 	for (;;) {
872 		set_current_state(TASK_INTERRUPTIBLE);
873 		if (mutex_lock_interruptible(&usblp->mut)) {
874 			rc = -EINTR;
875 			break;
876 		}
877 		rc = usblp_wtest(usblp, nonblock);
878 		mutex_unlock(&usblp->mut);
879 		if (rc <= 0)
880 			break;
881 
882 		if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
883 			if (usblp->flags & LP_ABORT) {
884 				err = usblp_check_status(usblp, err);
885 				if (err == 1) {	/* Paper out */
886 					rc = -ENOSPC;
887 					break;
888 				}
889 			} else {
890 				/* Prod the printer, Gentoo#251237. */
891 				mutex_lock(&usblp->mut);
892 				usblp_read_status(usblp, usblp->statusbuf);
893 				mutex_unlock(&usblp->mut);
894 			}
895 		}
896 	}
897 	set_current_state(TASK_RUNNING);
898 	remove_wait_queue(&usblp->wwait, &waita);
899 	return rc;
900 }
901 
902 static int usblp_wtest(struct usblp *usblp, int nonblock)
903 {
904 	unsigned long flags;
905 
906 	if (!usblp->present)
907 		return -ENODEV;
908 	if (signal_pending(current))
909 		return -EINTR;
910 	spin_lock_irqsave(&usblp->lock, flags);
911 	if (usblp->wcomplete) {
912 		spin_unlock_irqrestore(&usblp->lock, flags);
913 		return 0;
914 	}
915 	spin_unlock_irqrestore(&usblp->lock, flags);
916 	if (nonblock)
917 		return -EAGAIN;
918 	return 1;
919 }
920 
921 /*
922  * Wait for read bytes to become available. This probably should have been
923  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
924  * name for functions which lock and return.
925  *
926  * We do not use wait_event_interruptible because it makes locking iffy.
927  */
928 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
929 {
930 	DECLARE_WAITQUEUE(waita, current);
931 	int rc;
932 
933 	add_wait_queue(&usblp->rwait, &waita);
934 	for (;;) {
935 		if (mutex_lock_interruptible(&usblp->mut)) {
936 			rc = -EINTR;
937 			break;
938 		}
939 		set_current_state(TASK_INTERRUPTIBLE);
940 		if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
941 			mutex_unlock(&usblp->mut);
942 			break;
943 		}
944 		if (rc == 0)	/* Keep it locked */
945 			break;
946 		mutex_unlock(&usblp->mut);
947 		schedule();
948 	}
949 	set_current_state(TASK_RUNNING);
950 	remove_wait_queue(&usblp->rwait, &waita);
951 	return rc;
952 }
953 
954 static int usblp_rtest(struct usblp *usblp, int nonblock)
955 {
956 	unsigned long flags;
957 
958 	if (!usblp->present)
959 		return -ENODEV;
960 	if (signal_pending(current))
961 		return -EINTR;
962 	spin_lock_irqsave(&usblp->lock, flags);
963 	if (usblp->rcomplete) {
964 		spin_unlock_irqrestore(&usblp->lock, flags);
965 		return 0;
966 	}
967 	spin_unlock_irqrestore(&usblp->lock, flags);
968 	if (nonblock)
969 		return -EAGAIN;
970 	return 1;
971 }
972 
973 /*
974  * Please check ->bidir and other such things outside for now.
975  */
976 static int usblp_submit_read(struct usblp *usblp)
977 {
978 	struct urb *urb;
979 	unsigned long flags;
980 	int rc;
981 
982 	rc = -ENOMEM;
983 	if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL)
984 		goto raise_urb;
985 
986 	usb_fill_bulk_urb(urb, usblp->dev,
987 		usb_rcvbulkpipe(usblp->dev,
988 		  usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
989 		usblp->readbuf, USBLP_BUF_SIZE_IN,
990 		usblp_bulk_read, usblp);
991 	usb_anchor_urb(urb, &usblp->urbs);
992 
993 	spin_lock_irqsave(&usblp->lock, flags);
994 	usblp->readcount = 0; /* XXX Why here? */
995 	usblp->rcomplete = 0;
996 	spin_unlock_irqrestore(&usblp->lock, flags);
997 	if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
998 		dev_dbg(&usblp->intf->dev, "error submitting urb (%d)\n", rc);
999 		spin_lock_irqsave(&usblp->lock, flags);
1000 		usblp->rstatus = rc;
1001 		usblp->rcomplete = 1;
1002 		spin_unlock_irqrestore(&usblp->lock, flags);
1003 		goto raise_submit;
1004 	}
1005 
1006 	return 0;
1007 
1008 raise_submit:
1009 	usb_unanchor_urb(urb);
1010 	usb_free_urb(urb);
1011 raise_urb:
1012 	return rc;
1013 }
1014 
1015 /*
1016  * Checks for printers that have quirks, such as requiring unidirectional
1017  * communication but reporting bidirectional; currently some HP printers
1018  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1019  * sent at each open (like some Epsons).
1020  * Returns 1 if found, 0 if not found.
1021  *
1022  * HP recommended that we use the bidirectional interface but
1023  * don't attempt any bulk IN transfers from the IN endpoint.
1024  * Here's some more detail on the problem:
1025  * The problem is not that it isn't bidirectional though. The problem
1026  * is that if you request a device ID, or status information, while
1027  * the buffers are full, the return data will end up in the print data
1028  * buffer. For example if you make sure you never request the device ID
1029  * while you are sending print data, and you don't try to query the
1030  * printer status every couple of milliseconds, you will probably be OK.
1031  */
1032 static unsigned int usblp_quirks(__u16 vendor, __u16 product)
1033 {
1034 	int i;
1035 
1036 	for (i = 0; quirk_printers[i].vendorId; i++) {
1037 		if (vendor == quirk_printers[i].vendorId &&
1038 		    product == quirk_printers[i].productId)
1039 			return quirk_printers[i].quirks;
1040 	}
1041 	return 0;
1042 }
1043 
1044 static const struct file_operations usblp_fops = {
1045 	.owner =	THIS_MODULE,
1046 	.read =		usblp_read,
1047 	.write =	usblp_write,
1048 	.poll =		usblp_poll,
1049 	.unlocked_ioctl =	usblp_ioctl,
1050 	.compat_ioctl =		usblp_ioctl,
1051 	.open =		usblp_open,
1052 	.release =	usblp_release,
1053 	.llseek =	noop_llseek,
1054 };
1055 
1056 static char *usblp_devnode(struct device *dev, umode_t *mode)
1057 {
1058 	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1059 }
1060 
1061 static struct usb_class_driver usblp_class = {
1062 	.name =		"lp%d",
1063 	.devnode =	usblp_devnode,
1064 	.fops =		&usblp_fops,
1065 	.minor_base =	USBLP_MINOR_BASE,
1066 };
1067 
1068 static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
1069 {
1070 	struct usb_interface *intf = to_usb_interface(dev);
1071 	struct usblp *usblp = usb_get_intfdata(intf);
1072 
1073 	if (usblp->device_id_string[0] == 0 &&
1074 	    usblp->device_id_string[1] == 0)
1075 		return 0;
1076 
1077 	return sprintf(buf, "%s", usblp->device_id_string+2);
1078 }
1079 
1080 static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
1081 
1082 static int usblp_probe(struct usb_interface *intf,
1083 		       const struct usb_device_id *id)
1084 {
1085 	struct usb_device *dev = interface_to_usbdev(intf);
1086 	struct usblp *usblp;
1087 	int protocol;
1088 	int retval;
1089 
1090 	/* Malloc and start initializing usblp structure so we can use it
1091 	 * directly. */
1092 	usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1093 	if (!usblp) {
1094 		retval = -ENOMEM;
1095 		goto abort_ret;
1096 	}
1097 	usblp->dev = dev;
1098 	mutex_init(&usblp->wmut);
1099 	mutex_init(&usblp->mut);
1100 	spin_lock_init(&usblp->lock);
1101 	init_waitqueue_head(&usblp->rwait);
1102 	init_waitqueue_head(&usblp->wwait);
1103 	init_usb_anchor(&usblp->urbs);
1104 	usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1105 	usblp->intf = intf;
1106 
1107 	/* Malloc device ID string buffer to the largest expected length,
1108 	 * since we can re-query it on an ioctl and a dynamic string
1109 	 * could change in length. */
1110 	if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1111 		retval = -ENOMEM;
1112 		goto abort;
1113 	}
1114 
1115 	/*
1116 	 * Allocate read buffer. We somewhat wastefully
1117 	 * malloc both regardless of bidirectionality, because the
1118 	 * alternate setting can be changed later via an ioctl.
1119 	 */
1120 	if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1121 		retval = -ENOMEM;
1122 		goto abort;
1123 	}
1124 
1125 	/* Allocate buffer for printer status */
1126 	usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1127 	if (!usblp->statusbuf) {
1128 		retval = -ENOMEM;
1129 		goto abort;
1130 	}
1131 
1132 	/* Lookup quirks for this printer. */
1133 	usblp->quirks = usblp_quirks(
1134 		le16_to_cpu(dev->descriptor.idVendor),
1135 		le16_to_cpu(dev->descriptor.idProduct));
1136 
1137 	/* Analyze and pick initial alternate settings and endpoints. */
1138 	protocol = usblp_select_alts(usblp);
1139 	if (protocol < 0) {
1140 		dev_dbg(&intf->dev,
1141 			"incompatible printer-class device 0x%4.4X/0x%4.4X\n",
1142 			le16_to_cpu(dev->descriptor.idVendor),
1143 			le16_to_cpu(dev->descriptor.idProduct));
1144 		retval = -ENODEV;
1145 		goto abort;
1146 	}
1147 
1148 	/* Setup the selected alternate setting and endpoints. */
1149 	if (usblp_set_protocol(usblp, protocol) < 0) {
1150 		retval = -ENODEV;	/* ->probe isn't ->ioctl */
1151 		goto abort;
1152 	}
1153 
1154 	/* Retrieve and store the device ID string. */
1155 	usblp_cache_device_id_string(usblp);
1156 	retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1157 	if (retval)
1158 		goto abort_intfdata;
1159 
1160 #ifdef DEBUG
1161 	usblp_check_status(usblp, 0);
1162 #endif
1163 
1164 	usb_set_intfdata(intf, usblp);
1165 
1166 	usblp->present = 1;
1167 
1168 	retval = usb_register_dev(intf, &usblp_class);
1169 	if (retval) {
1170 		dev_err(&intf->dev,
1171 			"usblp: Not able to get a minor (base %u, slice default): %d\n",
1172 			USBLP_MINOR_BASE, retval);
1173 		goto abort_intfdata;
1174 	}
1175 	usblp->minor = intf->minor;
1176 	dev_info(&intf->dev,
1177 		"usblp%d: USB %sdirectional printer dev %d if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1178 		usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1179 		usblp->ifnum,
1180 		usblp->protocol[usblp->current_protocol].alt_setting,
1181 		usblp->current_protocol,
1182 		le16_to_cpu(usblp->dev->descriptor.idVendor),
1183 		le16_to_cpu(usblp->dev->descriptor.idProduct));
1184 
1185 	return 0;
1186 
1187 abort_intfdata:
1188 	usb_set_intfdata(intf, NULL);
1189 	device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1190 abort:
1191 	kfree(usblp->readbuf);
1192 	kfree(usblp->statusbuf);
1193 	kfree(usblp->device_id_string);
1194 	kfree(usblp);
1195 abort_ret:
1196 	return retval;
1197 }
1198 
1199 /*
1200  * We are a "new" style driver with usb_device_id table,
1201  * but our requirements are too intricate for simple match to handle.
1202  *
1203  * The "proto_bias" option may be used to specify the preferred protocol
1204  * for all USB printers (1=7/1/1, 2=7/1/2, 3=7/1/3).  If the device
1205  * supports the preferred protocol, then we bind to it.
1206  *
1207  * The best interface for us is 7/1/2, because it is compatible
1208  * with a stream of characters. If we find it, we bind to it.
1209  *
1210  * Note that the people from hpoj.sourceforge.net need to be able to
1211  * bind to 7/1/3 (MLC/1284.4), so we provide them ioctls for this purpose.
1212  *
1213  * Failing 7/1/2, we look for 7/1/3, even though it's probably not
1214  * stream-compatible, because this matches the behaviour of the old code.
1215  *
1216  * If nothing else, we bind to 7/1/1 - the unidirectional interface.
1217  */
1218 static int usblp_select_alts(struct usblp *usblp)
1219 {
1220 	struct usb_interface *if_alt;
1221 	struct usb_host_interface *ifd;
1222 	struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1223 	int p, i, e;
1224 
1225 	if_alt = usblp->intf;
1226 
1227 	for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1228 		usblp->protocol[p].alt_setting = -1;
1229 
1230 	/* Find out what we have. */
1231 	for (i = 0; i < if_alt->num_altsetting; i++) {
1232 		ifd = &if_alt->altsetting[i];
1233 
1234 		if (ifd->desc.bInterfaceClass != 7 || ifd->desc.bInterfaceSubClass != 1)
1235 			if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1236 				continue;
1237 
1238 		if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1239 		    ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1240 			continue;
1241 
1242 		/* Look for bulk OUT and IN endpoints. */
1243 		epwrite = epread = NULL;
1244 		for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1245 			epd = &ifd->endpoint[e].desc;
1246 
1247 			if (usb_endpoint_is_bulk_out(epd))
1248 				if (!epwrite)
1249 					epwrite = epd;
1250 
1251 			if (usb_endpoint_is_bulk_in(epd))
1252 				if (!epread)
1253 					epread = epd;
1254 		}
1255 
1256 		/* Ignore buggy hardware without the right endpoints. */
1257 		if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1258 			continue;
1259 
1260 		/* Turn off reads for 7/1/1 (unidirectional) interfaces
1261 		 * and buggy bidirectional printers. */
1262 		if (ifd->desc.bInterfaceProtocol == 1) {
1263 			epread = NULL;
1264 		} else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1265 			printk(KERN_INFO "usblp%d: Disabling reads from "
1266 			    "problematic bidirectional printer\n",
1267 			    usblp->minor);
1268 			epread = NULL;
1269 		}
1270 
1271 		usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1272 				ifd->desc.bAlternateSetting;
1273 		usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1274 		usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1275 	}
1276 
1277 	/* If our requested protocol is supported, then use it. */
1278 	if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1279 	    proto_bias <= USBLP_LAST_PROTOCOL &&
1280 	    usblp->protocol[proto_bias].alt_setting != -1)
1281 		return proto_bias;
1282 
1283 	/* Ordering is important here. */
1284 	if (usblp->protocol[2].alt_setting != -1)
1285 		return 2;
1286 	if (usblp->protocol[1].alt_setting != -1)
1287 		return 1;
1288 	if (usblp->protocol[3].alt_setting != -1)
1289 		return 3;
1290 
1291 	/* If nothing is available, then don't bind to this device. */
1292 	return -1;
1293 }
1294 
1295 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1296 {
1297 	int r, alts;
1298 
1299 	if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1300 		return -EINVAL;
1301 
1302 	alts = usblp->protocol[protocol].alt_setting;
1303 	if (alts < 0)
1304 		return -EINVAL;
1305 	r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1306 	if (r < 0) {
1307 		printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1308 			alts, usblp->ifnum);
1309 		return r;
1310 	}
1311 
1312 	usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1313 	usblp->current_protocol = protocol;
1314 	dev_dbg(&usblp->intf->dev, "usblp%d set protocol %d\n",
1315 		usblp->minor, protocol);
1316 	return 0;
1317 }
1318 
1319 /* Retrieves and caches device ID string.
1320  * Returns length, including length bytes but not null terminator.
1321  * On error, returns a negative errno value. */
1322 static int usblp_cache_device_id_string(struct usblp *usblp)
1323 {
1324 	int err, length;
1325 
1326 	err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1327 	if (err < 0) {
1328 		dev_dbg(&usblp->intf->dev,
1329 			"usblp%d: error = %d reading IEEE-1284 Device ID string\n",
1330 			usblp->minor, err);
1331 		usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1332 		return -EIO;
1333 	}
1334 
1335 	/* First two bytes are length in big-endian.
1336 	 * They count themselves, and we copy them into
1337 	 * the user's buffer. */
1338 	length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1339 	if (length < 2)
1340 		length = 2;
1341 	else if (length >= USBLP_DEVICE_ID_SIZE)
1342 		length = USBLP_DEVICE_ID_SIZE - 1;
1343 	usblp->device_id_string[length] = '\0';
1344 
1345 	dev_dbg(&usblp->intf->dev, "usblp%d Device ID string [len=%d]=\"%s\"\n",
1346 		usblp->minor, length, &usblp->device_id_string[2]);
1347 
1348 	return length;
1349 }
1350 
1351 static void usblp_disconnect(struct usb_interface *intf)
1352 {
1353 	struct usblp *usblp = usb_get_intfdata(intf);
1354 
1355 	usb_deregister_dev(intf, &usblp_class);
1356 
1357 	if (!usblp || !usblp->dev) {
1358 		dev_err(&intf->dev, "bogus disconnect\n");
1359 		BUG();
1360 	}
1361 
1362 	device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1363 
1364 	mutex_lock(&usblp_mutex);
1365 	mutex_lock(&usblp->mut);
1366 	usblp->present = 0;
1367 	wake_up(&usblp->wwait);
1368 	wake_up(&usblp->rwait);
1369 	usb_set_intfdata(intf, NULL);
1370 
1371 	usblp_unlink_urbs(usblp);
1372 	mutex_unlock(&usblp->mut);
1373 
1374 	if (!usblp->used)
1375 		usblp_cleanup(usblp);
1376 	mutex_unlock(&usblp_mutex);
1377 }
1378 
1379 static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1380 {
1381 	struct usblp *usblp = usb_get_intfdata(intf);
1382 
1383 	usblp_unlink_urbs(usblp);
1384 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1385 	/* not strictly necessary, but just in case */
1386 	wake_up(&usblp->wwait);
1387 	wake_up(&usblp->rwait);
1388 #endif
1389 
1390 	return 0;
1391 }
1392 
1393 static int usblp_resume(struct usb_interface *intf)
1394 {
1395 	struct usblp *usblp = usb_get_intfdata(intf);
1396 	int r;
1397 
1398 	r = handle_bidir(usblp);
1399 
1400 	return r;
1401 }
1402 
1403 static const struct usb_device_id usblp_ids[] = {
1404 	{ USB_DEVICE_INFO(7, 1, 1) },
1405 	{ USB_DEVICE_INFO(7, 1, 2) },
1406 	{ USB_DEVICE_INFO(7, 1, 3) },
1407 	{ USB_INTERFACE_INFO(7, 1, 1) },
1408 	{ USB_INTERFACE_INFO(7, 1, 2) },
1409 	{ USB_INTERFACE_INFO(7, 1, 3) },
1410 	{ USB_DEVICE(0x04b8, 0x0202) },	/* Seiko Epson Receipt Printer M129C */
1411 	{ }						/* Terminating entry */
1412 };
1413 
1414 MODULE_DEVICE_TABLE(usb, usblp_ids);
1415 
1416 static struct usb_driver usblp_driver = {
1417 	.name =		"usblp",
1418 	.probe =	usblp_probe,
1419 	.disconnect =	usblp_disconnect,
1420 	.suspend =	usblp_suspend,
1421 	.resume =	usblp_resume,
1422 	.id_table =	usblp_ids,
1423 	.supports_autosuspend =	1,
1424 };
1425 
1426 module_usb_driver(usblp_driver);
1427 
1428 MODULE_AUTHOR(DRIVER_AUTHOR);
1429 MODULE_DESCRIPTION(DRIVER_DESC);
1430 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1431 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1432 MODULE_LICENSE("GPL");
1433