1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * usblp.c
4 *
5 * Copyright (c) 1999 Michael Gee <michael@linuxspecific.com>
6 * Copyright (c) 1999 Pavel Machek <pavel@ucw.cz>
7 * Copyright (c) 2000 Randy Dunlap <rdunlap@xenotime.net>
8 * Copyright (c) 2000 Vojtech Pavlik <vojtech@suse.cz>
9 # Copyright (c) 2001 Pete Zaitcev <zaitcev@redhat.com>
10 # Copyright (c) 2001 David Paschal <paschal@rcsis.com>
11 * Copyright (c) 2006 Oliver Neukum <oliver@neukum.name>
12 *
13 * USB Printer Device Class driver for USB printers and printer cables
14 *
15 * Sponsored by SuSE
16 *
17 * ChangeLog:
18 * v0.1 - thorough cleaning, URBification, almost a rewrite
19 * v0.2 - some more cleanups
20 * v0.3 - cleaner again, waitqueue fixes
21 * v0.4 - fixes in unidirectional mode
22 * v0.5 - add DEVICE_ID string support
23 * v0.6 - never time out
24 * v0.7 - fixed bulk-IN read and poll (David Paschal)
25 * v0.8 - add devfs support
26 * v0.9 - fix unplug-while-open paths
27 * v0.10- remove sleep_on, fix error on oom (oliver@neukum.org)
28 * v0.11 - add proto_bias option (Pete Zaitcev)
29 * v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
30 * v0.13 - alloc space for statusbuf (<status> not on stack);
31 * use usb_alloc_coherent() for read buf & write buf;
32 * none - Maintained in Linux kernel after v0.13
33 */
34
35#include <linux/module.h>
36#include <linux/kernel.h>
37#include <linux/sched/signal.h>
38#include <linux/signal.h>
39#include <linux/poll.h>
40#include <linux/slab.h>
41#include <linux/lp.h>
42#include <linux/mutex.h>
43#undef DEBUG
44#include <linux/usb.h>
45#include <linux/usb/ch9.h>
46#include <linux/ratelimit.h>
47
48/*
49 * Version Information
50 */
51#define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
52#define DRIVER_DESC "USB Printer Device Class driver"
53
54#define USBLP_BUF_SIZE 8192
55#define USBLP_BUF_SIZE_IN 1024
56#define USBLP_DEVICE_ID_SIZE 1024
57
58/* ioctls: */
59#define IOCNR_GET_DEVICE_ID 1
60#define IOCNR_GET_PROTOCOLS 2
61#define IOCNR_SET_PROTOCOL 3
62#define IOCNR_HP_SET_CHANNEL 4
63#define IOCNR_GET_BUS_ADDRESS 5
64#define IOCNR_GET_VID_PID 6
65#define IOCNR_SOFT_RESET 7
66/* Get device_id string: */
67#define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
68/* The following ioctls were added for http://hpoj.sourceforge.net:
69 * Get two-int array:
70 * [0]=current protocol
71 * (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
72 * 3=USB_CLASS_PRINTER/1/3),
73 * [1]=supported protocol mask (mask&(1<<n)!=0 means
74 * USB_CLASS_PRINTER/1/n supported):
75 */
76#define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
77/*
78 * Set protocol
79 * (arg: 1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
80 * 3=USB_CLASS_PRINTER/1/3):
81 */
82#define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
83/* Set channel number (HP Vendor-specific command): */
84#define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
85/* Get two-int array: [0]=bus number, [1]=device address: */
86#define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
87/* Get two-int array: [0]=vendor ID, [1]=product ID: */
88#define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
89/* Perform class specific soft reset */
90#define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
91
92/*
93 * A DEVICE_ID string may include the printer's serial number.
94 * It should end with a semi-colon (';').
95 * An example from an HP 970C DeskJet printer is (this is one long string,
96 * with the serial number changed):
97MFG: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: ;
98 */
99
100/*
101 * USB Printer Requests
102 */
103
104#define USBLP_REQ_GET_ID 0x00
105#define USBLP_REQ_GET_STATUS 0x01
106#define USBLP_REQ_RESET 0x02
107#define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST 0x00 /* HP Vendor-specific */
108
109#define USBLP_MINORS 16
110#define USBLP_MINOR_BASE 0
111
112#define USBLP_CTL_TIMEOUT 5000 /* 5 seconds */
113
114#define USBLP_FIRST_PROTOCOL 1
115#define USBLP_LAST_PROTOCOL 3
116#define USBLP_MAX_PROTOCOLS (USBLP_LAST_PROTOCOL+1)
117
118/*
119 * some arbitrary status buffer size;
120 * need a status buffer that is allocated via kmalloc(), not on stack
121 */
122#define STATUS_BUF_SIZE 8
123
124/*
125 * Locks down the locking order:
126 * ->wmut locks wstatus.
127 * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
128 * [rw]status. We only touch status when we know the side idle.
129 * ->lock locks what interrupt accesses.
130 */
131struct usblp {
132 struct usb_device *dev; /* USB device */
133 struct mutex wmut;
134 struct mutex mut;
135 spinlock_t lock; /* locks rcomplete, wcomplete */
136 char *readbuf; /* read transfer_buffer */
137 char *statusbuf; /* status transfer_buffer */
138 struct usb_anchor urbs;
139 wait_queue_head_t rwait, wwait;
140 int readcount; /* Counter for reads */
141 int ifnum; /* Interface number */
142 struct usb_interface *intf; /* The interface */
143 /*
144 * Alternate-setting numbers and endpoints for each protocol
145 * (USB_CLASS_PRINTER/1/{index=1,2,3}) that the device supports:
146 */
147 struct {
148 int alt_setting;
149 struct usb_endpoint_descriptor *epwrite;
150 struct usb_endpoint_descriptor *epread;
151 } protocol[USBLP_MAX_PROTOCOLS];
152 int current_protocol;
153 int minor; /* minor number of device */
154 int wcomplete, rcomplete;
155 int wstatus; /* bytes written or error */
156 int rstatus; /* bytes ready or error */
157 unsigned int quirks; /* quirks flags */
158 unsigned int flags; /* mode flags */
159 unsigned char used; /* True if open */
160 unsigned char present; /* True if not disconnected */
161 unsigned char bidir; /* interface is bidirectional */
162 unsigned char no_paper; /* Paper Out happened */
163 unsigned char *device_id_string; /* IEEE 1284 DEVICE ID string (ptr) */
164 /* first 2 bytes are (big-endian) length */
165};
166
167#ifdef DEBUG
168static void usblp_dump(struct usblp *usblp)
169{
170 struct device *dev = &usblp->intf->dev;
171 int p;
172
173 dev_dbg(dev, "usblp=0x%p\n", usblp);
174 dev_dbg(dev, "dev=0x%p\n", usblp->dev);
175 dev_dbg(dev, "present=%d\n", usblp->present);
176 dev_dbg(dev, "readbuf=0x%p\n", usblp->readbuf);
177 dev_dbg(dev, "readcount=%d\n", usblp->readcount);
178 dev_dbg(dev, "ifnum=%d\n", usblp->ifnum);
179 for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
180 dev_dbg(dev, "protocol[%d].alt_setting=%d\n", p,
181 usblp->protocol[p].alt_setting);
182 dev_dbg(dev, "protocol[%d].epwrite=%p\n", p,
183 usblp->protocol[p].epwrite);
184 dev_dbg(dev, "protocol[%d].epread=%p\n", p,
185 usblp->protocol[p].epread);
186 }
187 dev_dbg(dev, "current_protocol=%d\n", usblp->current_protocol);
188 dev_dbg(dev, "minor=%d\n", usblp->minor);
189 dev_dbg(dev, "wstatus=%d\n", usblp->wstatus);
190 dev_dbg(dev, "rstatus=%d\n", usblp->rstatus);
191 dev_dbg(dev, "quirks=%d\n", usblp->quirks);
192 dev_dbg(dev, "used=%d\n", usblp->used);
193 dev_dbg(dev, "bidir=%d\n", usblp->bidir);
194 dev_dbg(dev, "device_id_string=\"%s\"\n",
195 usblp->device_id_string ?
196 usblp->device_id_string + 2 :
197 (unsigned char *)"(null)");
198}
199#endif
200
201/* Quirks: various printer quirks are handled by this table & its flags. */
202
203struct quirk_printer_struct {
204 __u16 vendorId;
205 __u16 productId;
206 unsigned int quirks;
207};
208
209#define USBLP_QUIRK_BIDIR 0x1 /* reports bidir but requires unidirectional mode (no INs/reads) */
210#define USBLP_QUIRK_USB_INIT 0x2 /* needs vendor USB init string */
211#define USBLP_QUIRK_BAD_CLASS 0x4 /* descriptor uses vendor-specific Class or SubClass */
212
213static const struct quirk_printer_struct quirk_printers[] = {
214 { 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
215 { 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
216 { 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
217 { 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
218 { 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
219 { 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
220 { 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
221 { 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
222 { 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
223 { 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
224 { 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
225 { 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
226 { 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
227 { 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <kernel@zut.de> */
228 { 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
229 { 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
230 { 0, 0 }
231};
232
233static int usblp_wwait(struct usblp *usblp, int nonblock);
234static int usblp_wtest(struct usblp *usblp, int nonblock);
235static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
236static int usblp_rtest(struct usblp *usblp, int nonblock);
237static int usblp_submit_read(struct usblp *usblp);
238static int usblp_select_alts(struct usblp *usblp);
239static int usblp_set_protocol(struct usblp *usblp, int protocol);
240static int usblp_cache_device_id_string(struct usblp *usblp);
241
242/* forward reference to make our lives easier */
243static struct usb_driver usblp_driver;
244static DEFINE_MUTEX(usblp_mutex); /* locks the existence of usblp's */
245
246/*
247 * Functions for usblp control messages.
248 */
249
250static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
251{
252 int retval;
253 int index = usblp->ifnum;
254
255 /* High byte has the interface index.
256 Low byte has the alternate setting.
257 */
258 if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS))
259 index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
260
261 retval = usb_control_msg(dev: usblp->dev,
262 pipe: dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
263 request, requesttype: type | dir | recip, value, index, data: buf, size: len, USBLP_CTL_TIMEOUT);
264 dev_dbg(&usblp->intf->dev,
265 "usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d\n",
266 request, !!dir, recip, value, index, len, retval);
267 return retval < 0 ? retval : 0;
268}
269
270#define usblp_read_status(usblp, status)\
271 usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
272#define usblp_get_id(usblp, config, id, maxlen)\
273 usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
274#define usblp_reset(usblp)\
275 usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
276
277static int usblp_hp_channel_change_request(struct usblp *usblp, int channel, u8 *new_channel)
278{
279 u8 *buf;
280 int ret;
281
282 buf = kzalloc(size: 1, GFP_KERNEL);
283 if (!buf)
284 return -ENOMEM;
285
286 ret = usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST,
287 USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE,
288 value: channel, buf, len: 1);
289 if (ret == 0)
290 *new_channel = buf[0];
291
292 kfree(objp: buf);
293
294 return ret;
295}
296
297/*
298 * See the description for usblp_select_alts() below for the usage
299 * explanation. Look into your /sys/kernel/debug/usb/devices and dmesg in
300 * case of any trouble.
301 */
302static int proto_bias = -1;
303
304/*
305 * URB callback.
306 */
307
308static void usblp_bulk_read(struct urb *urb)
309{
310 struct usblp *usblp = urb->context;
311 int status = urb->status;
312 unsigned long flags;
313
314 if (usblp->present && usblp->used) {
315 if (status)
316 printk(KERN_WARNING "usblp%d: "
317 "nonzero read bulk status received: %d\n",
318 usblp->minor, status);
319 }
320 spin_lock_irqsave(&usblp->lock, flags);
321 if (status < 0)
322 usblp->rstatus = status;
323 else
324 usblp->rstatus = urb->actual_length;
325 usblp->rcomplete = 1;
326 wake_up(&usblp->rwait);
327 spin_unlock_irqrestore(lock: &usblp->lock, flags);
328
329 usb_free_urb(urb);
330}
331
332static void usblp_bulk_write(struct urb *urb)
333{
334 struct usblp *usblp = urb->context;
335 int status = urb->status;
336 unsigned long flags;
337
338 if (usblp->present && usblp->used) {
339 if (status)
340 printk(KERN_WARNING "usblp%d: "
341 "nonzero write bulk status received: %d\n",
342 usblp->minor, status);
343 }
344 spin_lock_irqsave(&usblp->lock, flags);
345 if (status < 0)
346 usblp->wstatus = status;
347 else
348 usblp->wstatus = urb->actual_length;
349 usblp->no_paper = 0;
350 usblp->wcomplete = 1;
351 wake_up(&usblp->wwait);
352 spin_unlock_irqrestore(lock: &usblp->lock, flags);
353
354 usb_free_urb(urb);
355}
356
357/*
358 * Get and print printer errors.
359 */
360
361static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
362
363static int usblp_check_status(struct usblp *usblp, int err)
364{
365 unsigned char status, newerr = 0;
366 int error;
367
368 mutex_lock(&usblp->mut);
369 if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
370 mutex_unlock(lock: &usblp->mut);
371 printk_ratelimited(KERN_ERR
372 "usblp%d: error %d reading printer status\n",
373 usblp->minor, error);
374 return 0;
375 }
376 status = *usblp->statusbuf;
377 mutex_unlock(lock: &usblp->mut);
378
379 if (~status & LP_PERRORP)
380 newerr = 3;
381 if (status & LP_POUTPA)
382 newerr = 1;
383 if (~status & LP_PSELECD)
384 newerr = 2;
385
386 if (newerr != err) {
387 printk(KERN_INFO "usblp%d: %s\n",
388 usblp->minor, usblp_messages[newerr]);
389 }
390
391 return newerr;
392}
393
394static int handle_bidir(struct usblp *usblp)
395{
396 if (usblp->bidir && usblp->used) {
397 if (usblp_submit_read(usblp) < 0)
398 return -EIO;
399 }
400 return 0;
401}
402
403/*
404 * File op functions.
405 */
406
407static int usblp_open(struct inode *inode, struct file *file)
408{
409 int minor = iminor(inode);
410 struct usblp *usblp;
411 struct usb_interface *intf;
412 int retval;
413
414 if (minor < 0)
415 return -ENODEV;
416
417 mutex_lock(&usblp_mutex);
418
419 retval = -ENODEV;
420 intf = usb_find_interface(drv: &usblp_driver, minor);
421 if (!intf)
422 goto out;
423 usblp = usb_get_intfdata(intf);
424 if (!usblp || !usblp->dev || !usblp->present)
425 goto out;
426
427 retval = -EBUSY;
428 if (usblp->used)
429 goto out;
430
431 /*
432 * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
433 * - We do not want persistent state which close(2) does not clear
434 * - It is not used anyway, according to CUPS people
435 */
436
437 retval = usb_autopm_get_interface(intf);
438 if (retval < 0)
439 goto out;
440 usblp->used = 1;
441 file->private_data = usblp;
442
443 usblp->wcomplete = 1; /* we begin writeable */
444 usblp->wstatus = 0;
445 usblp->rcomplete = 0;
446
447 if (handle_bidir(usblp) < 0) {
448 usb_autopm_put_interface(intf);
449 usblp->used = 0;
450 file->private_data = NULL;
451 retval = -EIO;
452 }
453out:
454 mutex_unlock(lock: &usblp_mutex);
455 return retval;
456}
457
458static void usblp_cleanup(struct usblp *usblp)
459{
460 printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
461
462 kfree(objp: usblp->readbuf);
463 kfree(objp: usblp->device_id_string);
464 kfree(objp: usblp->statusbuf);
465 usb_put_intf(intf: usblp->intf);
466 kfree(objp: usblp);
467}
468
469static void usblp_unlink_urbs(struct usblp *usblp)
470{
471 usb_kill_anchored_urbs(anchor: &usblp->urbs);
472}
473
474static int usblp_release(struct inode *inode, struct file *file)
475{
476 struct usblp *usblp = file->private_data;
477
478 usblp->flags &= ~LP_ABORT;
479
480 mutex_lock(&usblp_mutex);
481 usblp->used = 0;
482 if (usblp->present)
483 usblp_unlink_urbs(usblp);
484
485 usb_autopm_put_interface(intf: usblp->intf);
486
487 if (!usblp->present) /* finish cleanup from disconnect */
488 usblp_cleanup(usblp); /* any URBs must be dead */
489
490 mutex_unlock(lock: &usblp_mutex);
491 return 0;
492}
493
494/* No kernel lock - fine */
495static __poll_t usblp_poll(struct file *file, struct poll_table_struct *wait)
496{
497 struct usblp *usblp = file->private_data;
498 __poll_t ret = 0;
499 unsigned long flags;
500
501 /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
502 poll_wait(filp: file, wait_address: &usblp->rwait, p: wait);
503 poll_wait(filp: file, wait_address: &usblp->wwait, p: wait);
504
505 mutex_lock(&usblp->mut);
506 if (!usblp->present)
507 ret |= EPOLLHUP;
508 mutex_unlock(lock: &usblp->mut);
509
510 spin_lock_irqsave(&usblp->lock, flags);
511 if (usblp->bidir && usblp->rcomplete)
512 ret |= EPOLLIN | EPOLLRDNORM;
513 if (usblp->no_paper || usblp->wcomplete)
514 ret |= EPOLLOUT | EPOLLWRNORM;
515 spin_unlock_irqrestore(lock: &usblp->lock, flags);
516 return ret;
517}
518
519static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
520{
521 struct usblp *usblp = file->private_data;
522 int length, err, i;
523 unsigned char newChannel;
524 int status;
525 int twoints[2];
526 int retval = 0;
527
528 mutex_lock(&usblp->mut);
529 if (!usblp->present) {
530 retval = -ENODEV;
531 goto done;
532 }
533
534 dev_dbg(&usblp->intf->dev,
535 "usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)\n", cmd,
536 _IOC_TYPE(cmd), _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
537
538 if (_IOC_TYPE(cmd) == 'P') /* new-style ioctl number */
539
540 switch (_IOC_NR(cmd)) {
541
542 case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
543 if (_IOC_DIR(cmd) != _IOC_READ) {
544 retval = -EINVAL;
545 goto done;
546 }
547
548 length = usblp_cache_device_id_string(usblp);
549 if (length < 0) {
550 retval = length;
551 goto done;
552 }
553 if (length > _IOC_SIZE(cmd))
554 length = _IOC_SIZE(cmd); /* truncate */
555
556 if (copy_to_user(to: (void __user *) arg,
557 from: usblp->device_id_string,
558 n: (unsigned long) length)) {
559 retval = -EFAULT;
560 goto done;
561 }
562
563 break;
564
565 case IOCNR_GET_PROTOCOLS:
566 if (_IOC_DIR(cmd) != _IOC_READ ||
567 _IOC_SIZE(cmd) < sizeof(twoints)) {
568 retval = -EINVAL;
569 goto done;
570 }
571
572 twoints[0] = usblp->current_protocol;
573 twoints[1] = 0;
574 for (i = USBLP_FIRST_PROTOCOL;
575 i <= USBLP_LAST_PROTOCOL; i++) {
576 if (usblp->protocol[i].alt_setting >= 0)
577 twoints[1] |= (1<<i);
578 }
579
580 if (copy_to_user(to: (void __user *)arg,
581 from: (unsigned char *)twoints,
582 n: sizeof(twoints))) {
583 retval = -EFAULT;
584 goto done;
585 }
586
587 break;
588
589 case IOCNR_SET_PROTOCOL:
590 if (_IOC_DIR(cmd) != _IOC_WRITE) {
591 retval = -EINVAL;
592 goto done;
593 }
594
595#ifdef DEBUG
596 if (arg == -10) {
597 usblp_dump(usblp);
598 break;
599 }
600#endif
601
602 usblp_unlink_urbs(usblp);
603 retval = usblp_set_protocol(usblp, protocol: arg);
604 if (retval < 0) {
605 usblp_set_protocol(usblp,
606 protocol: usblp->current_protocol);
607 }
608 break;
609
610 case IOCNR_HP_SET_CHANNEL:
611 if (_IOC_DIR(cmd) != _IOC_WRITE ||
612 le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
613 usblp->quirks & USBLP_QUIRK_BIDIR) {
614 retval = -EINVAL;
615 goto done;
616 }
617
618 err = usblp_hp_channel_change_request(usblp,
619 channel: arg, new_channel: &newChannel);
620 if (err < 0) {
621 dev_err(&usblp->dev->dev,
622 "usblp%d: error = %d setting "
623 "HP channel\n",
624 usblp->minor, err);
625 retval = -EIO;
626 goto done;
627 }
628
629 dev_dbg(&usblp->intf->dev,
630 "usblp%d requested/got HP channel %ld/%d\n",
631 usblp->minor, arg, newChannel);
632 break;
633
634 case IOCNR_GET_BUS_ADDRESS:
635 if (_IOC_DIR(cmd) != _IOC_READ ||
636 _IOC_SIZE(cmd) < sizeof(twoints)) {
637 retval = -EINVAL;
638 goto done;
639 }
640
641 twoints[0] = usblp->dev->bus->busnum;
642 twoints[1] = usblp->dev->devnum;
643 if (copy_to_user(to: (void __user *)arg,
644 from: (unsigned char *)twoints,
645 n: sizeof(twoints))) {
646 retval = -EFAULT;
647 goto done;
648 }
649
650 dev_dbg(&usblp->intf->dev,
651 "usblp%d is bus=%d, device=%d\n",
652 usblp->minor, twoints[0], twoints[1]);
653 break;
654
655 case IOCNR_GET_VID_PID:
656 if (_IOC_DIR(cmd) != _IOC_READ ||
657 _IOC_SIZE(cmd) < sizeof(twoints)) {
658 retval = -EINVAL;
659 goto done;
660 }
661
662 twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
663 twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
664 if (copy_to_user(to: (void __user *)arg,
665 from: (unsigned char *)twoints,
666 n: sizeof(twoints))) {
667 retval = -EFAULT;
668 goto done;
669 }
670
671 dev_dbg(&usblp->intf->dev,
672 "usblp%d is VID=0x%4.4X, PID=0x%4.4X\n",
673 usblp->minor, twoints[0], twoints[1]);
674 break;
675
676 case IOCNR_SOFT_RESET:
677 if (_IOC_DIR(cmd) != _IOC_NONE) {
678 retval = -EINVAL;
679 goto done;
680 }
681 retval = usblp_reset(usblp);
682 break;
683 default:
684 retval = -ENOTTY;
685 }
686 else /* old-style ioctl value */
687 switch (cmd) {
688
689 case LPGETSTATUS:
690 retval = usblp_read_status(usblp, usblp->statusbuf);
691 if (retval) {
692 printk_ratelimited(KERN_ERR "usblp%d:"
693 "failed reading printer status (%d)\n",
694 usblp->minor, retval);
695 retval = -EIO;
696 goto done;
697 }
698 status = *usblp->statusbuf;
699 if (copy_to_user(to: (void __user *)arg, from: &status, n: sizeof(int)))
700 retval = -EFAULT;
701 break;
702
703 case LPABORT:
704 if (arg)
705 usblp->flags |= LP_ABORT;
706 else
707 usblp->flags &= ~LP_ABORT;
708 break;
709
710 default:
711 retval = -ENOTTY;
712 }
713
714done:
715 mutex_unlock(lock: &usblp->mut);
716 return retval;
717}
718
719static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
720{
721 struct urb *urb;
722 char *writebuf;
723
724 writebuf = kmalloc(size: transfer_length, GFP_KERNEL);
725 if (writebuf == NULL)
726 return NULL;
727 urb = usb_alloc_urb(iso_packets: 0, GFP_KERNEL);
728 if (urb == NULL) {
729 kfree(objp: writebuf);
730 return NULL;
731 }
732
733 usb_fill_bulk_urb(urb, dev: usblp->dev,
734 usb_sndbulkpipe(usblp->dev,
735 usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
736 transfer_buffer: writebuf, buffer_length: transfer_length, complete_fn: usblp_bulk_write, context: usblp);
737 urb->transfer_flags |= URB_FREE_BUFFER;
738
739 return urb;
740}
741
742static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
743{
744 struct usblp *usblp = file->private_data;
745 struct urb *writeurb;
746 int rv;
747 int transfer_length;
748 ssize_t writecount = 0;
749
750 if (mutex_lock_interruptible(&usblp->wmut)) {
751 rv = -EINTR;
752 goto raise_biglock;
753 }
754 if ((rv = usblp_wwait(usblp, nonblock: !!(file->f_flags & O_NONBLOCK))) < 0)
755 goto raise_wait;
756
757 while (writecount < count) {
758 /*
759 * Step 1: Submit next block.
760 */
761 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
762 transfer_length = USBLP_BUF_SIZE;
763
764 rv = -ENOMEM;
765 writeurb = usblp_new_writeurb(usblp, transfer_length);
766 if (writeurb == NULL)
767 goto raise_urb;
768 usb_anchor_urb(urb: writeurb, anchor: &usblp->urbs);
769
770 if (copy_from_user(to: writeurb->transfer_buffer,
771 from: buffer + writecount, n: transfer_length)) {
772 rv = -EFAULT;
773 goto raise_badaddr;
774 }
775
776 spin_lock_irq(lock: &usblp->lock);
777 usblp->wcomplete = 0;
778 spin_unlock_irq(lock: &usblp->lock);
779 if ((rv = usb_submit_urb(urb: writeurb, GFP_KERNEL)) < 0) {
780 usblp->wstatus = 0;
781 spin_lock_irq(lock: &usblp->lock);
782 usblp->no_paper = 0;
783 usblp->wcomplete = 1;
784 wake_up(&usblp->wwait);
785 spin_unlock_irq(lock: &usblp->lock);
786 if (rv != -ENOMEM)
787 rv = -EIO;
788 goto raise_submit;
789 }
790
791 /*
792 * Step 2: Wait for transfer to end, collect results.
793 */
794 rv = usblp_wwait(usblp, nonblock: !!(file->f_flags&O_NONBLOCK));
795 if (rv < 0) {
796 if (rv == -EAGAIN) {
797 /* Presume that it's going to complete well. */
798 writecount += transfer_length;
799 }
800 if (rv == -ENOSPC) {
801 spin_lock_irq(lock: &usblp->lock);
802 usblp->no_paper = 1; /* Mark for poll(2) */
803 spin_unlock_irq(lock: &usblp->lock);
804 writecount += transfer_length;
805 }
806 /* Leave URB dangling, to be cleaned on close. */
807 goto collect_error;
808 }
809
810 if (usblp->wstatus < 0) {
811 rv = -EIO;
812 goto collect_error;
813 }
814 /*
815 * This is critical: it must be our URB, not other writer's.
816 * The wmut exists mainly to cover us here.
817 */
818 writecount += usblp->wstatus;
819 }
820
821 mutex_unlock(lock: &usblp->wmut);
822 return writecount;
823
824raise_submit:
825raise_badaddr:
826 usb_unanchor_urb(urb: writeurb);
827 usb_free_urb(urb: writeurb);
828raise_urb:
829raise_wait:
830collect_error: /* Out of raise sequence */
831 mutex_unlock(lock: &usblp->wmut);
832raise_biglock:
833 return writecount ? writecount : rv;
834}
835
836/*
837 * Notice that we fail to restart in a few cases: on EFAULT, on restart
838 * error, etc. This is the historical behaviour. In all such cases we return
839 * EIO, and applications loop in order to get the new read going.
840 */
841static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
842{
843 struct usblp *usblp = file->private_data;
844 ssize_t count;
845 ssize_t avail;
846 int rv;
847
848 if (!usblp->bidir)
849 return -EINVAL;
850
851 rv = usblp_rwait_and_lock(usblp, nonblock: !!(file->f_flags & O_NONBLOCK));
852 if (rv < 0)
853 return rv;
854
855 if (!usblp->present) {
856 count = -ENODEV;
857 goto done;
858 }
859
860 if ((avail = usblp->rstatus) < 0) {
861 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
862 usblp->minor, (int)avail);
863 usblp_submit_read(usblp);
864 count = -EIO;
865 goto done;
866 }
867
868 count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
869 if (count != 0 &&
870 copy_to_user(to: buffer, from: usblp->readbuf + usblp->readcount, n: count)) {
871 count = -EFAULT;
872 goto done;
873 }
874
875 if ((usblp->readcount += count) == avail) {
876 if (usblp_submit_read(usblp) < 0) {
877 /* We don't want to leak USB return codes into errno. */
878 if (count == 0)
879 count = -EIO;
880 goto done;
881 }
882 }
883
884done:
885 mutex_unlock(lock: &usblp->mut);
886 return count;
887}
888
889/*
890 * Wait for the write path to come idle.
891 * This is called under the ->wmut, so the idle path stays idle.
892 *
893 * Our write path has a peculiar property: it does not buffer like a tty,
894 * but waits for the write to succeed. This allows our ->release to bug out
895 * without waiting for writes to drain. But it obviously does not work
896 * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
897 * select(2) or poll(2) to wait for the buffer to drain before closing.
898 * Alternatively, set blocking mode with fcntl and issue a zero-size write.
899 */
900static int usblp_wwait(struct usblp *usblp, int nonblock)
901{
902 DECLARE_WAITQUEUE(waita, current);
903 int rc;
904 int err = 0;
905
906 add_wait_queue(wq_head: &usblp->wwait, wq_entry: &waita);
907 for (;;) {
908 if (mutex_lock_interruptible(&usblp->mut)) {
909 rc = -EINTR;
910 break;
911 }
912 set_current_state(TASK_INTERRUPTIBLE);
913 rc = usblp_wtest(usblp, nonblock);
914 mutex_unlock(lock: &usblp->mut);
915 if (rc <= 0)
916 break;
917
918 if (schedule_timeout(timeout: msecs_to_jiffies(m: 1500)) == 0) {
919 if (usblp->flags & LP_ABORT) {
920 err = usblp_check_status(usblp, err);
921 if (err == 1) { /* Paper out */
922 rc = -ENOSPC;
923 break;
924 }
925 } else {
926 /* Prod the printer, Gentoo#251237. */
927 mutex_lock(&usblp->mut);
928 usblp_read_status(usblp, usblp->statusbuf);
929 mutex_unlock(lock: &usblp->mut);
930 }
931 }
932 }
933 set_current_state(TASK_RUNNING);
934 remove_wait_queue(wq_head: &usblp->wwait, wq_entry: &waita);
935 return rc;
936}
937
938static int usblp_wtest(struct usblp *usblp, int nonblock)
939{
940 unsigned long flags;
941
942 if (!usblp->present)
943 return -ENODEV;
944 if (signal_pending(current))
945 return -EINTR;
946 spin_lock_irqsave(&usblp->lock, flags);
947 if (usblp->wcomplete) {
948 spin_unlock_irqrestore(lock: &usblp->lock, flags);
949 return 0;
950 }
951 spin_unlock_irqrestore(lock: &usblp->lock, flags);
952 if (nonblock)
953 return -EAGAIN;
954 return 1;
955}
956
957/*
958 * Wait for read bytes to become available. This probably should have been
959 * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
960 * name for functions which lock and return.
961 *
962 * We do not use wait_event_interruptible because it makes locking iffy.
963 */
964static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
965{
966 DECLARE_WAITQUEUE(waita, current);
967 int rc;
968
969 add_wait_queue(wq_head: &usblp->rwait, wq_entry: &waita);
970 for (;;) {
971 if (mutex_lock_interruptible(&usblp->mut)) {
972 rc = -EINTR;
973 break;
974 }
975 set_current_state(TASK_INTERRUPTIBLE);
976 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
977 mutex_unlock(lock: &usblp->mut);
978 break;
979 }
980 if (rc == 0) /* Keep it locked */
981 break;
982 mutex_unlock(lock: &usblp->mut);
983 schedule();
984 }
985 set_current_state(TASK_RUNNING);
986 remove_wait_queue(wq_head: &usblp->rwait, wq_entry: &waita);
987 return rc;
988}
989
990static int usblp_rtest(struct usblp *usblp, int nonblock)
991{
992 unsigned long flags;
993
994 if (!usblp->present)
995 return -ENODEV;
996 if (signal_pending(current))
997 return -EINTR;
998 spin_lock_irqsave(&usblp->lock, flags);
999 if (usblp->rcomplete) {
1000 spin_unlock_irqrestore(lock: &usblp->lock, flags);
1001 return 0;
1002 }
1003 spin_unlock_irqrestore(lock: &usblp->lock, flags);
1004 if (nonblock)
1005 return -EAGAIN;
1006 return 1;
1007}
1008
1009/*
1010 * Please check ->bidir and other such things outside for now.
1011 */
1012static int usblp_submit_read(struct usblp *usblp)
1013{
1014 struct urb *urb;
1015 unsigned long flags;
1016 int rc;
1017
1018 rc = -ENOMEM;
1019 urb = usb_alloc_urb(iso_packets: 0, GFP_KERNEL);
1020 if (urb == NULL)
1021 goto raise_urb;
1022
1023 usb_fill_bulk_urb(urb, dev: usblp->dev,
1024 usb_rcvbulkpipe(usblp->dev,
1025 usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
1026 transfer_buffer: usblp->readbuf, USBLP_BUF_SIZE_IN,
1027 complete_fn: usblp_bulk_read, context: usblp);
1028 usb_anchor_urb(urb, anchor: &usblp->urbs);
1029
1030 spin_lock_irqsave(&usblp->lock, flags);
1031 usblp->readcount = 0; /* XXX Why here? */
1032 usblp->rcomplete = 0;
1033 spin_unlock_irqrestore(lock: &usblp->lock, flags);
1034 if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
1035 dev_dbg(&usblp->intf->dev, "error submitting urb (%d)\n", rc);
1036 spin_lock_irqsave(&usblp->lock, flags);
1037 usblp->rstatus = rc;
1038 usblp->rcomplete = 1;
1039 spin_unlock_irqrestore(lock: &usblp->lock, flags);
1040 goto raise_submit;
1041 }
1042
1043 return 0;
1044
1045raise_submit:
1046 usb_unanchor_urb(urb);
1047 usb_free_urb(urb);
1048raise_urb:
1049 return rc;
1050}
1051
1052/*
1053 * Checks for printers that have quirks, such as requiring unidirectional
1054 * communication but reporting bidirectional; currently some HP printers
1055 * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1056 * sent at each open (like some Epsons).
1057 * Returns 1 if found, 0 if not found.
1058 *
1059 * HP recommended that we use the bidirectional interface but
1060 * don't attempt any bulk IN transfers from the IN endpoint.
1061 * Here's some more detail on the problem:
1062 * The problem is not that it isn't bidirectional though. The problem
1063 * is that if you request a device ID, or status information, while
1064 * the buffers are full, the return data will end up in the print data
1065 * buffer. For example if you make sure you never request the device ID
1066 * while you are sending print data, and you don't try to query the
1067 * printer status every couple of milliseconds, you will probably be OK.
1068 */
1069static unsigned int usblp_quirks(__u16 vendor, __u16 product)
1070{
1071 int i;
1072
1073 for (i = 0; quirk_printers[i].vendorId; i++) {
1074 if (vendor == quirk_printers[i].vendorId &&
1075 product == quirk_printers[i].productId)
1076 return quirk_printers[i].quirks;
1077 }
1078 return 0;
1079}
1080
1081static const struct file_operations usblp_fops = {
1082 .owner = THIS_MODULE,
1083 .read = usblp_read,
1084 .write = usblp_write,
1085 .poll = usblp_poll,
1086 .unlocked_ioctl = usblp_ioctl,
1087 .compat_ioctl = usblp_ioctl,
1088 .open = usblp_open,
1089 .release = usblp_release,
1090 .llseek = noop_llseek,
1091};
1092
1093static char *usblp_devnode(const struct device *dev, umode_t *mode)
1094{
1095 return kasprintf(GFP_KERNEL, fmt: "usb/%s", dev_name(dev));
1096}
1097
1098static struct usb_class_driver usblp_class = {
1099 .name = "lp%d",
1100 .devnode = usblp_devnode,
1101 .fops = &usblp_fops,
1102 .minor_base = USBLP_MINOR_BASE,
1103};
1104
1105static ssize_t ieee1284_id_show(struct device *dev, struct device_attribute *attr, char *buf)
1106{
1107 struct usb_interface *intf = to_usb_interface(dev);
1108 struct usblp *usblp = usb_get_intfdata(intf);
1109
1110 if (usblp->device_id_string[0] == 0 &&
1111 usblp->device_id_string[1] == 0)
1112 return 0;
1113
1114 return sprintf(buf, fmt: "%s", usblp->device_id_string+2);
1115}
1116
1117static DEVICE_ATTR_RO(ieee1284_id);
1118
1119static struct attribute *usblp_attrs[] = {
1120 &dev_attr_ieee1284_id.attr,
1121 NULL,
1122};
1123ATTRIBUTE_GROUPS(usblp);
1124
1125static int usblp_probe(struct usb_interface *intf,
1126 const struct usb_device_id *id)
1127{
1128 struct usb_device *dev = interface_to_usbdev(intf);
1129 struct usblp *usblp;
1130 int protocol;
1131 int retval;
1132
1133 /* Malloc and start initializing usblp structure so we can use it
1134 * directly. */
1135 usblp = kzalloc(size: sizeof(struct usblp), GFP_KERNEL);
1136 if (!usblp) {
1137 retval = -ENOMEM;
1138 goto abort_ret;
1139 }
1140 usblp->dev = dev;
1141 mutex_init(&usblp->wmut);
1142 mutex_init(&usblp->mut);
1143 spin_lock_init(&usblp->lock);
1144 init_waitqueue_head(&usblp->rwait);
1145 init_waitqueue_head(&usblp->wwait);
1146 init_usb_anchor(anchor: &usblp->urbs);
1147 usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1148 usblp->intf = usb_get_intf(intf);
1149
1150 /* Malloc device ID string buffer to the largest expected length,
1151 * since we can re-query it on an ioctl and a dynamic string
1152 * could change in length. */
1153 if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1154 retval = -ENOMEM;
1155 goto abort;
1156 }
1157
1158 /*
1159 * Allocate read buffer. We somewhat wastefully
1160 * malloc both regardless of bidirectionality, because the
1161 * alternate setting can be changed later via an ioctl.
1162 */
1163 if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1164 retval = -ENOMEM;
1165 goto abort;
1166 }
1167
1168 /* Allocate buffer for printer status */
1169 usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1170 if (!usblp->statusbuf) {
1171 retval = -ENOMEM;
1172 goto abort;
1173 }
1174
1175 /* Lookup quirks for this printer. */
1176 usblp->quirks = usblp_quirks(
1177 le16_to_cpu(dev->descriptor.idVendor),
1178 le16_to_cpu(dev->descriptor.idProduct));
1179
1180 /* Analyze and pick initial alternate settings and endpoints. */
1181 protocol = usblp_select_alts(usblp);
1182 if (protocol < 0) {
1183 dev_dbg(&intf->dev,
1184 "incompatible printer-class device 0x%4.4X/0x%4.4X\n",
1185 le16_to_cpu(dev->descriptor.idVendor),
1186 le16_to_cpu(dev->descriptor.idProduct));
1187 retval = -ENODEV;
1188 goto abort;
1189 }
1190
1191 /* Setup the selected alternate setting and endpoints. */
1192 if (usblp_set_protocol(usblp, protocol) < 0) {
1193 retval = -ENODEV; /* ->probe isn't ->ioctl */
1194 goto abort;
1195 }
1196
1197 /* Retrieve and store the device ID string. */
1198 usblp_cache_device_id_string(usblp);
1199
1200#ifdef DEBUG
1201 usblp_check_status(usblp, 0);
1202#endif
1203
1204 usb_set_intfdata(intf, data: usblp);
1205
1206 usblp->present = 1;
1207
1208 retval = usb_register_dev(intf, class_driver: &usblp_class);
1209 if (retval) {
1210 dev_err(&intf->dev,
1211 "usblp: Not able to get a minor (base %u, slice default): %d\n",
1212 USBLP_MINOR_BASE, retval);
1213 goto abort_intfdata;
1214 }
1215 usblp->minor = intf->minor;
1216 dev_info(&intf->dev,
1217 "usblp%d: USB %sdirectional printer dev %d if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1218 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1219 usblp->ifnum,
1220 usblp->protocol[usblp->current_protocol].alt_setting,
1221 usblp->current_protocol,
1222 le16_to_cpu(usblp->dev->descriptor.idVendor),
1223 le16_to_cpu(usblp->dev->descriptor.idProduct));
1224
1225 return 0;
1226
1227abort_intfdata:
1228 usb_set_intfdata(intf, NULL);
1229abort:
1230 kfree(objp: usblp->readbuf);
1231 kfree(objp: usblp->statusbuf);
1232 kfree(objp: usblp->device_id_string);
1233 usb_put_intf(intf: usblp->intf);
1234 kfree(objp: usblp);
1235abort_ret:
1236 return retval;
1237}
1238
1239/*
1240 * We are a "new" style driver with usb_device_id table,
1241 * but our requirements are too intricate for simple match to handle.
1242 *
1243 * The "proto_bias" option may be used to specify the preferred protocol
1244 * for all USB printers (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
1245 * 3=USB_CLASS_PRINTER/1/3). If the device supports the preferred protocol,
1246 * then we bind to it.
1247 *
1248 * The best interface for us is USB_CLASS_PRINTER/1/2, because it
1249 * is compatible with a stream of characters. If we find it, we bind to it.
1250 *
1251 * Note that the people from hpoj.sourceforge.net need to be able to
1252 * bind to USB_CLASS_PRINTER/1/3 (MLC/1284.4), so we provide them ioctls
1253 * for this purpose.
1254 *
1255 * Failing USB_CLASS_PRINTER/1/2, we look for USB_CLASS_PRINTER/1/3,
1256 * even though it's probably not stream-compatible, because this matches
1257 * the behaviour of the old code.
1258 *
1259 * If nothing else, we bind to USB_CLASS_PRINTER/1/1
1260 * - the unidirectional interface.
1261 */
1262static int usblp_select_alts(struct usblp *usblp)
1263{
1264 struct usb_interface *if_alt;
1265 struct usb_host_interface *ifd;
1266 struct usb_endpoint_descriptor *epwrite, *epread;
1267 int p, i;
1268 int res;
1269
1270 if_alt = usblp->intf;
1271
1272 for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1273 usblp->protocol[p].alt_setting = -1;
1274
1275 /* Find out what we have. */
1276 for (i = 0; i < if_alt->num_altsetting; i++) {
1277 ifd = &if_alt->altsetting[i];
1278
1279 if (ifd->desc.bInterfaceClass != USB_CLASS_PRINTER ||
1280 ifd->desc.bInterfaceSubClass != 1)
1281 if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1282 continue;
1283
1284 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1285 ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1286 continue;
1287
1288 /* Look for the expected bulk endpoints. */
1289 if (ifd->desc.bInterfaceProtocol > 1) {
1290 res = usb_find_common_endpoints(alt: ifd,
1291 bulk_in: &epread, bulk_out: &epwrite, NULL, NULL);
1292 } else {
1293 epread = NULL;
1294 res = usb_find_bulk_out_endpoint(alt: ifd, bulk_out: &epwrite);
1295 }
1296
1297 /* Ignore buggy hardware without the right endpoints. */
1298 if (res)
1299 continue;
1300
1301 /* Turn off reads for buggy bidirectional printers. */
1302 if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1303 printk(KERN_INFO "usblp%d: Disabling reads from "
1304 "problematic bidirectional printer\n",
1305 usblp->minor);
1306 epread = NULL;
1307 }
1308
1309 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1310 ifd->desc.bAlternateSetting;
1311 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1312 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1313 }
1314
1315 /* If our requested protocol is supported, then use it. */
1316 if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1317 proto_bias <= USBLP_LAST_PROTOCOL &&
1318 usblp->protocol[proto_bias].alt_setting != -1)
1319 return proto_bias;
1320
1321 /* Ordering is important here. */
1322 if (usblp->protocol[2].alt_setting != -1)
1323 return 2;
1324 if (usblp->protocol[1].alt_setting != -1)
1325 return 1;
1326 if (usblp->protocol[3].alt_setting != -1)
1327 return 3;
1328
1329 /* If nothing is available, then don't bind to this device. */
1330 return -1;
1331}
1332
1333static int usblp_set_protocol(struct usblp *usblp, int protocol)
1334{
1335 int r, alts;
1336
1337 if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1338 return -EINVAL;
1339
1340 /* Don't unnecessarily set the interface if there's a single alt. */
1341 if (usblp->intf->num_altsetting > 1) {
1342 alts = usblp->protocol[protocol].alt_setting;
1343 if (alts < 0)
1344 return -EINVAL;
1345 r = usb_set_interface(dev: usblp->dev, ifnum: usblp->ifnum, alternate: alts);
1346 if (r < 0) {
1347 printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1348 alts, usblp->ifnum);
1349 return r;
1350 }
1351 }
1352
1353 usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1354 usblp->current_protocol = protocol;
1355 dev_dbg(&usblp->intf->dev, "usblp%d set protocol %d\n",
1356 usblp->minor, protocol);
1357 return 0;
1358}
1359
1360/* Retrieves and caches device ID string.
1361 * Returns length, including length bytes but not null terminator.
1362 * On error, returns a negative errno value. */
1363static int usblp_cache_device_id_string(struct usblp *usblp)
1364{
1365 int err, length;
1366
1367 err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1368 if (err < 0) {
1369 dev_dbg(&usblp->intf->dev,
1370 "usblp%d: error = %d reading IEEE-1284 Device ID string\n",
1371 usblp->minor, err);
1372 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1373 return -EIO;
1374 }
1375
1376 /* First two bytes are length in big-endian.
1377 * They count themselves, and we copy them into
1378 * the user's buffer. */
1379 length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1380 if (length < 2)
1381 length = 2;
1382 else if (length >= USBLP_DEVICE_ID_SIZE)
1383 length = USBLP_DEVICE_ID_SIZE - 1;
1384 usblp->device_id_string[length] = '\0';
1385
1386 dev_dbg(&usblp->intf->dev, "usblp%d Device ID string [len=%d]=\"%s\"\n",
1387 usblp->minor, length, &usblp->device_id_string[2]);
1388
1389 return length;
1390}
1391
1392static void usblp_disconnect(struct usb_interface *intf)
1393{
1394 struct usblp *usblp = usb_get_intfdata(intf);
1395
1396 usb_deregister_dev(intf, class_driver: &usblp_class);
1397
1398 if (!usblp || !usblp->dev) {
1399 dev_err(&intf->dev, "bogus disconnect\n");
1400 BUG();
1401 }
1402
1403 mutex_lock(&usblp_mutex);
1404 mutex_lock(&usblp->mut);
1405 usblp->present = 0;
1406 wake_up(&usblp->wwait);
1407 wake_up(&usblp->rwait);
1408 usb_set_intfdata(intf, NULL);
1409
1410 usblp_unlink_urbs(usblp);
1411 mutex_unlock(lock: &usblp->mut);
1412 usb_poison_anchored_urbs(anchor: &usblp->urbs);
1413
1414 if (!usblp->used)
1415 usblp_cleanup(usblp);
1416
1417 mutex_unlock(lock: &usblp_mutex);
1418}
1419
1420static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1421{
1422 struct usblp *usblp = usb_get_intfdata(intf);
1423
1424 usblp_unlink_urbs(usblp);
1425#if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1426 /* not strictly necessary, but just in case */
1427 wake_up(&usblp->wwait);
1428 wake_up(&usblp->rwait);
1429#endif
1430
1431 return 0;
1432}
1433
1434static int usblp_resume(struct usb_interface *intf)
1435{
1436 struct usblp *usblp = usb_get_intfdata(intf);
1437 int r;
1438
1439 r = handle_bidir(usblp);
1440
1441 return r;
1442}
1443
1444static const struct usb_device_id usblp_ids[] = {
1445 { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 1) },
1446 { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 2) },
1447 { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 3) },
1448 { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 1) },
1449 { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 2) },
1450 { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 3) },
1451 { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1452 { } /* Terminating entry */
1453};
1454
1455MODULE_DEVICE_TABLE(usb, usblp_ids);
1456
1457static struct usb_driver usblp_driver = {
1458 .name = "usblp",
1459 .probe = usblp_probe,
1460 .disconnect = usblp_disconnect,
1461 .suspend = usblp_suspend,
1462 .resume = usblp_resume,
1463 .id_table = usblp_ids,
1464 .dev_groups = usblp_groups,
1465 .supports_autosuspend = 1,
1466};
1467
1468module_usb_driver(usblp_driver);
1469
1470MODULE_AUTHOR(DRIVER_AUTHOR);
1471MODULE_DESCRIPTION(DRIVER_DESC);
1472module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1473MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1474MODULE_LICENSE("GPL");
1475

source code of linux/drivers/usb/class/usblp.c