Linux-libre 5.4.49-gnu
[librecmc/linux-libre.git] / drivers / usb / class / usblp.c
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):
97 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:                    ;
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  */
131 struct 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
168 static 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
203 struct 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
213 static 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
233 static int usblp_wwait(struct usblp *usblp, int nonblock);
234 static int usblp_wtest(struct usblp *usblp, int nonblock);
235 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
236 static int usblp_rtest(struct usblp *usblp, int nonblock);
237 static int usblp_submit_read(struct usblp *usblp);
238 static int usblp_select_alts(struct usblp *usblp);
239 static int usblp_set_protocol(struct usblp *usblp, int protocol);
240 static int usblp_cache_device_id_string(struct usblp *usblp);
241
242 /* forward reference to make our lives easier */
243 static struct usb_driver usblp_driver;
244 static DEFINE_MUTEX(usblp_mutex);       /* locks the existence of usblp's */
245
246 /*
247  * Functions for usblp control messages.
248  */
249
250 static 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(usblp->dev,
262                 dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
263                 request, type | dir | recip, value, index, buf, 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
277 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
278         usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
279
280 /*
281  * See the description for usblp_select_alts() below for the usage
282  * explanation.  Look into your /sys/kernel/debug/usb/devices and dmesg in
283  * case of any trouble.
284  */
285 static int proto_bias = -1;
286
287 /*
288  * URB callback.
289  */
290
291 static void usblp_bulk_read(struct urb *urb)
292 {
293         struct usblp *usblp = urb->context;
294         int status = urb->status;
295         unsigned long flags;
296
297         if (usblp->present && usblp->used) {
298                 if (status)
299                         printk(KERN_WARNING "usblp%d: "
300                             "nonzero read bulk status received: %d\n",
301                             usblp->minor, status);
302         }
303         spin_lock_irqsave(&usblp->lock, flags);
304         if (status < 0)
305                 usblp->rstatus = status;
306         else
307                 usblp->rstatus = urb->actual_length;
308         usblp->rcomplete = 1;
309         wake_up(&usblp->rwait);
310         spin_unlock_irqrestore(&usblp->lock, flags);
311
312         usb_free_urb(urb);
313 }
314
315 static void usblp_bulk_write(struct urb *urb)
316 {
317         struct usblp *usblp = urb->context;
318         int status = urb->status;
319         unsigned long flags;
320
321         if (usblp->present && usblp->used) {
322                 if (status)
323                         printk(KERN_WARNING "usblp%d: "
324                             "nonzero write bulk status received: %d\n",
325                             usblp->minor, status);
326         }
327         spin_lock_irqsave(&usblp->lock, flags);
328         if (status < 0)
329                 usblp->wstatus = status;
330         else
331                 usblp->wstatus = urb->actual_length;
332         usblp->no_paper = 0;
333         usblp->wcomplete = 1;
334         wake_up(&usblp->wwait);
335         spin_unlock_irqrestore(&usblp->lock, flags);
336
337         usb_free_urb(urb);
338 }
339
340 /*
341  * Get and print printer errors.
342  */
343
344 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
345
346 static int usblp_check_status(struct usblp *usblp, int err)
347 {
348         unsigned char status, newerr = 0;
349         int error;
350
351         mutex_lock(&usblp->mut);
352         if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
353                 mutex_unlock(&usblp->mut);
354                 printk_ratelimited(KERN_ERR
355                                 "usblp%d: error %d reading printer status\n",
356                                 usblp->minor, error);
357                 return 0;
358         }
359         status = *usblp->statusbuf;
360         mutex_unlock(&usblp->mut);
361
362         if (~status & LP_PERRORP)
363                 newerr = 3;
364         if (status & LP_POUTPA)
365                 newerr = 1;
366         if (~status & LP_PSELECD)
367                 newerr = 2;
368
369         if (newerr != err) {
370                 printk(KERN_INFO "usblp%d: %s\n",
371                    usblp->minor, usblp_messages[newerr]);
372         }
373
374         return newerr;
375 }
376
377 static int handle_bidir(struct usblp *usblp)
378 {
379         if (usblp->bidir && usblp->used) {
380                 if (usblp_submit_read(usblp) < 0)
381                         return -EIO;
382         }
383         return 0;
384 }
385
386 /*
387  * File op functions.
388  */
389
390 static int usblp_open(struct inode *inode, struct file *file)
391 {
392         int minor = iminor(inode);
393         struct usblp *usblp;
394         struct usb_interface *intf;
395         int retval;
396
397         if (minor < 0)
398                 return -ENODEV;
399
400         mutex_lock(&usblp_mutex);
401
402         retval = -ENODEV;
403         intf = usb_find_interface(&usblp_driver, minor);
404         if (!intf)
405                 goto out;
406         usblp = usb_get_intfdata(intf);
407         if (!usblp || !usblp->dev || !usblp->present)
408                 goto out;
409
410         retval = -EBUSY;
411         if (usblp->used)
412                 goto out;
413
414         /*
415          * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
416          *  - We do not want persistent state which close(2) does not clear
417          *  - It is not used anyway, according to CUPS people
418          */
419
420         retval = usb_autopm_get_interface(intf);
421         if (retval < 0)
422                 goto out;
423         usblp->used = 1;
424         file->private_data = usblp;
425
426         usblp->wcomplete = 1; /* we begin writeable */
427         usblp->wstatus = 0;
428         usblp->rcomplete = 0;
429
430         if (handle_bidir(usblp) < 0) {
431                 usb_autopm_put_interface(intf);
432                 usblp->used = 0;
433                 file->private_data = NULL;
434                 retval = -EIO;
435         }
436 out:
437         mutex_unlock(&usblp_mutex);
438         return retval;
439 }
440
441 static void usblp_cleanup(struct usblp *usblp)
442 {
443         printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
444
445         kfree(usblp->readbuf);
446         kfree(usblp->device_id_string);
447         kfree(usblp->statusbuf);
448         usb_put_intf(usblp->intf);
449         kfree(usblp);
450 }
451
452 static void usblp_unlink_urbs(struct usblp *usblp)
453 {
454         usb_kill_anchored_urbs(&usblp->urbs);
455 }
456
457 static int usblp_release(struct inode *inode, struct file *file)
458 {
459         struct usblp *usblp = file->private_data;
460
461         usblp->flags &= ~LP_ABORT;
462
463         mutex_lock(&usblp_mutex);
464         usblp->used = 0;
465         if (usblp->present)
466                 usblp_unlink_urbs(usblp);
467
468         usb_autopm_put_interface(usblp->intf);
469
470         if (!usblp->present)            /* finish cleanup from disconnect */
471                 usblp_cleanup(usblp);   /* any URBs must be dead */
472
473         mutex_unlock(&usblp_mutex);
474         return 0;
475 }
476
477 /* No kernel lock - fine */
478 static __poll_t usblp_poll(struct file *file, struct poll_table_struct *wait)
479 {
480         __poll_t ret;
481         unsigned long flags;
482
483         struct usblp *usblp = file->private_data;
484         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
485         poll_wait(file, &usblp->rwait, wait);
486         poll_wait(file, &usblp->wwait, wait);
487         spin_lock_irqsave(&usblp->lock, flags);
488         ret = ((usblp->bidir && usblp->rcomplete) ? EPOLLIN  | EPOLLRDNORM : 0) |
489            ((usblp->no_paper || usblp->wcomplete) ? EPOLLOUT | EPOLLWRNORM : 0);
490         spin_unlock_irqrestore(&usblp->lock, flags);
491         return ret;
492 }
493
494 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
495 {
496         struct usblp *usblp = file->private_data;
497         int length, err, i;
498         unsigned char newChannel;
499         int status;
500         int twoints[2];
501         int retval = 0;
502
503         mutex_lock(&usblp->mut);
504         if (!usblp->present) {
505                 retval = -ENODEV;
506                 goto done;
507         }
508
509         dev_dbg(&usblp->intf->dev,
510                 "usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)\n", cmd,
511                 _IOC_TYPE(cmd), _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
512
513         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
514
515                 switch (_IOC_NR(cmd)) {
516
517                 case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
518                         if (_IOC_DIR(cmd) != _IOC_READ) {
519                                 retval = -EINVAL;
520                                 goto done;
521                         }
522
523                         length = usblp_cache_device_id_string(usblp);
524                         if (length < 0) {
525                                 retval = length;
526                                 goto done;
527                         }
528                         if (length > _IOC_SIZE(cmd))
529                                 length = _IOC_SIZE(cmd); /* truncate */
530
531                         if (copy_to_user((void __user *) arg,
532                                         usblp->device_id_string,
533                                         (unsigned long) length)) {
534                                 retval = -EFAULT;
535                                 goto done;
536                         }
537
538                         break;
539
540                 case IOCNR_GET_PROTOCOLS:
541                         if (_IOC_DIR(cmd) != _IOC_READ ||
542                             _IOC_SIZE(cmd) < sizeof(twoints)) {
543                                 retval = -EINVAL;
544                                 goto done;
545                         }
546
547                         twoints[0] = usblp->current_protocol;
548                         twoints[1] = 0;
549                         for (i = USBLP_FIRST_PROTOCOL;
550                              i <= USBLP_LAST_PROTOCOL; i++) {
551                                 if (usblp->protocol[i].alt_setting >= 0)
552                                         twoints[1] |= (1<<i);
553                         }
554
555                         if (copy_to_user((void __user *)arg,
556                                         (unsigned char *)twoints,
557                                         sizeof(twoints))) {
558                                 retval = -EFAULT;
559                                 goto done;
560                         }
561
562                         break;
563
564                 case IOCNR_SET_PROTOCOL:
565                         if (_IOC_DIR(cmd) != _IOC_WRITE) {
566                                 retval = -EINVAL;
567                                 goto done;
568                         }
569
570 #ifdef DEBUG
571                         if (arg == -10) {
572                                 usblp_dump(usblp);
573                                 break;
574                         }
575 #endif
576
577                         usblp_unlink_urbs(usblp);
578                         retval = usblp_set_protocol(usblp, arg);
579                         if (retval < 0) {
580                                 usblp_set_protocol(usblp,
581                                         usblp->current_protocol);
582                         }
583                         break;
584
585                 case IOCNR_HP_SET_CHANNEL:
586                         if (_IOC_DIR(cmd) != _IOC_WRITE ||
587                             le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
588                             usblp->quirks & USBLP_QUIRK_BIDIR) {
589                                 retval = -EINVAL;
590                                 goto done;
591                         }
592
593                         err = usblp_hp_channel_change_request(usblp,
594                                 arg, &newChannel);
595                         if (err < 0) {
596                                 dev_err(&usblp->dev->dev,
597                                         "usblp%d: error = %d setting "
598                                         "HP channel\n",
599                                         usblp->minor, err);
600                                 retval = -EIO;
601                                 goto done;
602                         }
603
604                         dev_dbg(&usblp->intf->dev,
605                                 "usblp%d requested/got HP channel %ld/%d\n",
606                                 usblp->minor, arg, newChannel);
607                         break;
608
609                 case IOCNR_GET_BUS_ADDRESS:
610                         if (_IOC_DIR(cmd) != _IOC_READ ||
611                             _IOC_SIZE(cmd) < sizeof(twoints)) {
612                                 retval = -EINVAL;
613                                 goto done;
614                         }
615
616                         twoints[0] = usblp->dev->bus->busnum;
617                         twoints[1] = usblp->dev->devnum;
618                         if (copy_to_user((void __user *)arg,
619                                         (unsigned char *)twoints,
620                                         sizeof(twoints))) {
621                                 retval = -EFAULT;
622                                 goto done;
623                         }
624
625                         dev_dbg(&usblp->intf->dev,
626                                 "usblp%d is bus=%d, device=%d\n",
627                                 usblp->minor, twoints[0], twoints[1]);
628                         break;
629
630                 case IOCNR_GET_VID_PID:
631                         if (_IOC_DIR(cmd) != _IOC_READ ||
632                             _IOC_SIZE(cmd) < sizeof(twoints)) {
633                                 retval = -EINVAL;
634                                 goto done;
635                         }
636
637                         twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
638                         twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
639                         if (copy_to_user((void __user *)arg,
640                                         (unsigned char *)twoints,
641                                         sizeof(twoints))) {
642                                 retval = -EFAULT;
643                                 goto done;
644                         }
645
646                         dev_dbg(&usblp->intf->dev,
647                                 "usblp%d is VID=0x%4.4X, PID=0x%4.4X\n",
648                                 usblp->minor, twoints[0], twoints[1]);
649                         break;
650
651                 case IOCNR_SOFT_RESET:
652                         if (_IOC_DIR(cmd) != _IOC_NONE) {
653                                 retval = -EINVAL;
654                                 goto done;
655                         }
656                         retval = usblp_reset(usblp);
657                         break;
658                 default:
659                         retval = -ENOTTY;
660                 }
661         else    /* old-style ioctl value */
662                 switch (cmd) {
663
664                 case LPGETSTATUS:
665                         retval = usblp_read_status(usblp, usblp->statusbuf);
666                         if (retval) {
667                                 printk_ratelimited(KERN_ERR "usblp%d:"
668                                             "failed reading printer status (%d)\n",
669                                             usblp->minor, retval);
670                                 retval = -EIO;
671                                 goto done;
672                         }
673                         status = *usblp->statusbuf;
674                         if (copy_to_user((void __user *)arg, &status, sizeof(int)))
675                                 retval = -EFAULT;
676                         break;
677
678                 case LPABORT:
679                         if (arg)
680                                 usblp->flags |= LP_ABORT;
681                         else
682                                 usblp->flags &= ~LP_ABORT;
683                         break;
684
685                 default:
686                         retval = -ENOTTY;
687                 }
688
689 done:
690         mutex_unlock(&usblp->mut);
691         return retval;
692 }
693
694 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
695 {
696         struct urb *urb;
697         char *writebuf;
698
699         writebuf = kmalloc(transfer_length, GFP_KERNEL);
700         if (writebuf == NULL)
701                 return NULL;
702         urb = usb_alloc_urb(0, GFP_KERNEL);
703         if (urb == NULL) {
704                 kfree(writebuf);
705                 return NULL;
706         }
707
708         usb_fill_bulk_urb(urb, usblp->dev,
709                 usb_sndbulkpipe(usblp->dev,
710                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
711                 writebuf, transfer_length, usblp_bulk_write, usblp);
712         urb->transfer_flags |= URB_FREE_BUFFER;
713
714         return urb;
715 }
716
717 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
718 {
719         struct usblp *usblp = file->private_data;
720         struct urb *writeurb;
721         int rv;
722         int transfer_length;
723         ssize_t writecount = 0;
724
725         if (mutex_lock_interruptible(&usblp->wmut)) {
726                 rv = -EINTR;
727                 goto raise_biglock;
728         }
729         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
730                 goto raise_wait;
731
732         while (writecount < count) {
733                 /*
734                  * Step 1: Submit next block.
735                  */
736                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
737                         transfer_length = USBLP_BUF_SIZE;
738
739                 rv = -ENOMEM;
740                 writeurb = usblp_new_writeurb(usblp, transfer_length);
741                 if (writeurb == NULL)
742                         goto raise_urb;
743                 usb_anchor_urb(writeurb, &usblp->urbs);
744
745                 if (copy_from_user(writeurb->transfer_buffer,
746                                    buffer + writecount, transfer_length)) {
747                         rv = -EFAULT;
748                         goto raise_badaddr;
749                 }
750
751                 spin_lock_irq(&usblp->lock);
752                 usblp->wcomplete = 0;
753                 spin_unlock_irq(&usblp->lock);
754                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
755                         usblp->wstatus = 0;
756                         spin_lock_irq(&usblp->lock);
757                         usblp->no_paper = 0;
758                         usblp->wcomplete = 1;
759                         wake_up(&usblp->wwait);
760                         spin_unlock_irq(&usblp->lock);
761                         if (rv != -ENOMEM)
762                                 rv = -EIO;
763                         goto raise_submit;
764                 }
765
766                 /*
767                  * Step 2: Wait for transfer to end, collect results.
768                  */
769                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
770                 if (rv < 0) {
771                         if (rv == -EAGAIN) {
772                                 /* Presume that it's going to complete well. */
773                                 writecount += transfer_length;
774                         }
775                         if (rv == -ENOSPC) {
776                                 spin_lock_irq(&usblp->lock);
777                                 usblp->no_paper = 1;    /* Mark for poll(2) */
778                                 spin_unlock_irq(&usblp->lock);
779                                 writecount += transfer_length;
780                         }
781                         /* Leave URB dangling, to be cleaned on close. */
782                         goto collect_error;
783                 }
784
785                 if (usblp->wstatus < 0) {
786                         rv = -EIO;
787                         goto collect_error;
788                 }
789                 /*
790                  * This is critical: it must be our URB, not other writer's.
791                  * The wmut exists mainly to cover us here.
792                  */
793                 writecount += usblp->wstatus;
794         }
795
796         mutex_unlock(&usblp->wmut);
797         return writecount;
798
799 raise_submit:
800 raise_badaddr:
801         usb_unanchor_urb(writeurb);
802         usb_free_urb(writeurb);
803 raise_urb:
804 raise_wait:
805 collect_error:          /* Out of raise sequence */
806         mutex_unlock(&usblp->wmut);
807 raise_biglock:
808         return writecount ? writecount : rv;
809 }
810
811 /*
812  * Notice that we fail to restart in a few cases: on EFAULT, on restart
813  * error, etc. This is the historical behaviour. In all such cases we return
814  * EIO, and applications loop in order to get the new read going.
815  */
816 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
817 {
818         struct usblp *usblp = file->private_data;
819         ssize_t count;
820         ssize_t avail;
821         int rv;
822
823         if (!usblp->bidir)
824                 return -EINVAL;
825
826         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
827         if (rv < 0)
828                 return rv;
829
830         if ((avail = usblp->rstatus) < 0) {
831                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
832                     usblp->minor, (int)avail);
833                 usblp_submit_read(usblp);
834                 count = -EIO;
835                 goto done;
836         }
837
838         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
839         if (count != 0 &&
840             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
841                 count = -EFAULT;
842                 goto done;
843         }
844
845         if ((usblp->readcount += count) == avail) {
846                 if (usblp_submit_read(usblp) < 0) {
847                         /* We don't want to leak USB return codes into errno. */
848                         if (count == 0)
849                                 count = -EIO;
850                         goto done;
851                 }
852         }
853
854 done:
855         mutex_unlock(&usblp->mut);
856         return count;
857 }
858
859 /*
860  * Wait for the write path to come idle.
861  * This is called under the ->wmut, so the idle path stays idle.
862  *
863  * Our write path has a peculiar property: it does not buffer like a tty,
864  * but waits for the write to succeed. This allows our ->release to bug out
865  * without waiting for writes to drain. But it obviously does not work
866  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
867  * select(2) or poll(2) to wait for the buffer to drain before closing.
868  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
869  */
870 static int usblp_wwait(struct usblp *usblp, int nonblock)
871 {
872         DECLARE_WAITQUEUE(waita, current);
873         int rc;
874         int err = 0;
875
876         add_wait_queue(&usblp->wwait, &waita);
877         for (;;) {
878                 if (mutex_lock_interruptible(&usblp->mut)) {
879                         rc = -EINTR;
880                         break;
881                 }
882                 set_current_state(TASK_INTERRUPTIBLE);
883                 rc = usblp_wtest(usblp, nonblock);
884                 mutex_unlock(&usblp->mut);
885                 if (rc <= 0)
886                         break;
887
888                 if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
889                         if (usblp->flags & LP_ABORT) {
890                                 err = usblp_check_status(usblp, err);
891                                 if (err == 1) { /* Paper out */
892                                         rc = -ENOSPC;
893                                         break;
894                                 }
895                         } else {
896                                 /* Prod the printer, Gentoo#251237. */
897                                 mutex_lock(&usblp->mut);
898                                 usblp_read_status(usblp, usblp->statusbuf);
899                                 mutex_unlock(&usblp->mut);
900                         }
901                 }
902         }
903         set_current_state(TASK_RUNNING);
904         remove_wait_queue(&usblp->wwait, &waita);
905         return rc;
906 }
907
908 static int usblp_wtest(struct usblp *usblp, int nonblock)
909 {
910         unsigned long flags;
911
912         if (!usblp->present)
913                 return -ENODEV;
914         if (signal_pending(current))
915                 return -EINTR;
916         spin_lock_irqsave(&usblp->lock, flags);
917         if (usblp->wcomplete) {
918                 spin_unlock_irqrestore(&usblp->lock, flags);
919                 return 0;
920         }
921         spin_unlock_irqrestore(&usblp->lock, flags);
922         if (nonblock)
923                 return -EAGAIN;
924         return 1;
925 }
926
927 /*
928  * Wait for read bytes to become available. This probably should have been
929  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
930  * name for functions which lock and return.
931  *
932  * We do not use wait_event_interruptible because it makes locking iffy.
933  */
934 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
935 {
936         DECLARE_WAITQUEUE(waita, current);
937         int rc;
938
939         add_wait_queue(&usblp->rwait, &waita);
940         for (;;) {
941                 if (mutex_lock_interruptible(&usblp->mut)) {
942                         rc = -EINTR;
943                         break;
944                 }
945                 set_current_state(TASK_INTERRUPTIBLE);
946                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
947                         mutex_unlock(&usblp->mut);
948                         break;
949                 }
950                 if (rc == 0)    /* Keep it locked */
951                         break;
952                 mutex_unlock(&usblp->mut);
953                 schedule();
954         }
955         set_current_state(TASK_RUNNING);
956         remove_wait_queue(&usblp->rwait, &waita);
957         return rc;
958 }
959
960 static int usblp_rtest(struct usblp *usblp, int nonblock)
961 {
962         unsigned long flags;
963
964         if (!usblp->present)
965                 return -ENODEV;
966         if (signal_pending(current))
967                 return -EINTR;
968         spin_lock_irqsave(&usblp->lock, flags);
969         if (usblp->rcomplete) {
970                 spin_unlock_irqrestore(&usblp->lock, flags);
971                 return 0;
972         }
973         spin_unlock_irqrestore(&usblp->lock, flags);
974         if (nonblock)
975                 return -EAGAIN;
976         return 1;
977 }
978
979 /*
980  * Please check ->bidir and other such things outside for now.
981  */
982 static int usblp_submit_read(struct usblp *usblp)
983 {
984         struct urb *urb;
985         unsigned long flags;
986         int rc;
987
988         rc = -ENOMEM;
989         urb = usb_alloc_urb(0, GFP_KERNEL);
990         if (urb == NULL)
991                 goto raise_urb;
992
993         usb_fill_bulk_urb(urb, usblp->dev,
994                 usb_rcvbulkpipe(usblp->dev,
995                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
996                 usblp->readbuf, USBLP_BUF_SIZE_IN,
997                 usblp_bulk_read, usblp);
998         usb_anchor_urb(urb, &usblp->urbs);
999
1000         spin_lock_irqsave(&usblp->lock, flags);
1001         usblp->readcount = 0; /* XXX Why here? */
1002         usblp->rcomplete = 0;
1003         spin_unlock_irqrestore(&usblp->lock, flags);
1004         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
1005                 dev_dbg(&usblp->intf->dev, "error submitting urb (%d)\n", rc);
1006                 spin_lock_irqsave(&usblp->lock, flags);
1007                 usblp->rstatus = rc;
1008                 usblp->rcomplete = 1;
1009                 spin_unlock_irqrestore(&usblp->lock, flags);
1010                 goto raise_submit;
1011         }
1012
1013         return 0;
1014
1015 raise_submit:
1016         usb_unanchor_urb(urb);
1017         usb_free_urb(urb);
1018 raise_urb:
1019         return rc;
1020 }
1021
1022 /*
1023  * Checks for printers that have quirks, such as requiring unidirectional
1024  * communication but reporting bidirectional; currently some HP printers
1025  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1026  * sent at each open (like some Epsons).
1027  * Returns 1 if found, 0 if not found.
1028  *
1029  * HP recommended that we use the bidirectional interface but
1030  * don't attempt any bulk IN transfers from the IN endpoint.
1031  * Here's some more detail on the problem:
1032  * The problem is not that it isn't bidirectional though. The problem
1033  * is that if you request a device ID, or status information, while
1034  * the buffers are full, the return data will end up in the print data
1035  * buffer. For example if you make sure you never request the device ID
1036  * while you are sending print data, and you don't try to query the
1037  * printer status every couple of milliseconds, you will probably be OK.
1038  */
1039 static unsigned int usblp_quirks(__u16 vendor, __u16 product)
1040 {
1041         int i;
1042
1043         for (i = 0; quirk_printers[i].vendorId; i++) {
1044                 if (vendor == quirk_printers[i].vendorId &&
1045                     product == quirk_printers[i].productId)
1046                         return quirk_printers[i].quirks;
1047         }
1048         return 0;
1049 }
1050
1051 static const struct file_operations usblp_fops = {
1052         .owner =        THIS_MODULE,
1053         .read =         usblp_read,
1054         .write =        usblp_write,
1055         .poll =         usblp_poll,
1056         .unlocked_ioctl =       usblp_ioctl,
1057         .compat_ioctl =         usblp_ioctl,
1058         .open =         usblp_open,
1059         .release =      usblp_release,
1060         .llseek =       noop_llseek,
1061 };
1062
1063 static char *usblp_devnode(struct device *dev, umode_t *mode)
1064 {
1065         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1066 }
1067
1068 static struct usb_class_driver usblp_class = {
1069         .name =         "lp%d",
1070         .devnode =      usblp_devnode,
1071         .fops =         &usblp_fops,
1072         .minor_base =   USBLP_MINOR_BASE,
1073 };
1074
1075 static ssize_t ieee1284_id_show(struct device *dev, struct device_attribute *attr, char *buf)
1076 {
1077         struct usb_interface *intf = to_usb_interface(dev);
1078         struct usblp *usblp = usb_get_intfdata(intf);
1079
1080         if (usblp->device_id_string[0] == 0 &&
1081             usblp->device_id_string[1] == 0)
1082                 return 0;
1083
1084         return sprintf(buf, "%s", usblp->device_id_string+2);
1085 }
1086
1087 static DEVICE_ATTR_RO(ieee1284_id);
1088
1089 static struct attribute *usblp_attrs[] = {
1090         &dev_attr_ieee1284_id.attr,
1091         NULL,
1092 };
1093 ATTRIBUTE_GROUPS(usblp);
1094
1095 static int usblp_probe(struct usb_interface *intf,
1096                        const struct usb_device_id *id)
1097 {
1098         struct usb_device *dev = interface_to_usbdev(intf);
1099         struct usblp *usblp;
1100         int protocol;
1101         int retval;
1102
1103         /* Malloc and start initializing usblp structure so we can use it
1104          * directly. */
1105         usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1106         if (!usblp) {
1107                 retval = -ENOMEM;
1108                 goto abort_ret;
1109         }
1110         usblp->dev = dev;
1111         mutex_init(&usblp->wmut);
1112         mutex_init(&usblp->mut);
1113         spin_lock_init(&usblp->lock);
1114         init_waitqueue_head(&usblp->rwait);
1115         init_waitqueue_head(&usblp->wwait);
1116         init_usb_anchor(&usblp->urbs);
1117         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1118         usblp->intf = usb_get_intf(intf);
1119
1120         /* Malloc device ID string buffer to the largest expected length,
1121          * since we can re-query it on an ioctl and a dynamic string
1122          * could change in length. */
1123         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1124                 retval = -ENOMEM;
1125                 goto abort;
1126         }
1127
1128         /*
1129          * Allocate read buffer. We somewhat wastefully
1130          * malloc both regardless of bidirectionality, because the
1131          * alternate setting can be changed later via an ioctl.
1132          */
1133         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1134                 retval = -ENOMEM;
1135                 goto abort;
1136         }
1137
1138         /* Allocate buffer for printer status */
1139         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1140         if (!usblp->statusbuf) {
1141                 retval = -ENOMEM;
1142                 goto abort;
1143         }
1144
1145         /* Lookup quirks for this printer. */
1146         usblp->quirks = usblp_quirks(
1147                 le16_to_cpu(dev->descriptor.idVendor),
1148                 le16_to_cpu(dev->descriptor.idProduct));
1149
1150         /* Analyze and pick initial alternate settings and endpoints. */
1151         protocol = usblp_select_alts(usblp);
1152         if (protocol < 0) {
1153                 dev_dbg(&intf->dev,
1154                         "incompatible printer-class device 0x%4.4X/0x%4.4X\n",
1155                         le16_to_cpu(dev->descriptor.idVendor),
1156                         le16_to_cpu(dev->descriptor.idProduct));
1157                 retval = -ENODEV;
1158                 goto abort;
1159         }
1160
1161         /* Setup the selected alternate setting and endpoints. */
1162         if (usblp_set_protocol(usblp, protocol) < 0) {
1163                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1164                 goto abort;
1165         }
1166
1167         /* Retrieve and store the device ID string. */
1168         usblp_cache_device_id_string(usblp);
1169
1170 #ifdef DEBUG
1171         usblp_check_status(usblp, 0);
1172 #endif
1173
1174         usb_set_intfdata(intf, usblp);
1175
1176         usblp->present = 1;
1177
1178         retval = usb_register_dev(intf, &usblp_class);
1179         if (retval) {
1180                 dev_err(&intf->dev,
1181                         "usblp: Not able to get a minor (base %u, slice default): %d\n",
1182                         USBLP_MINOR_BASE, retval);
1183                 goto abort_intfdata;
1184         }
1185         usblp->minor = intf->minor;
1186         dev_info(&intf->dev,
1187                 "usblp%d: USB %sdirectional printer dev %d if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1188                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1189                 usblp->ifnum,
1190                 usblp->protocol[usblp->current_protocol].alt_setting,
1191                 usblp->current_protocol,
1192                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1193                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1194
1195         return 0;
1196
1197 abort_intfdata:
1198         usb_set_intfdata(intf, NULL);
1199 abort:
1200         kfree(usblp->readbuf);
1201         kfree(usblp->statusbuf);
1202         kfree(usblp->device_id_string);
1203         usb_put_intf(usblp->intf);
1204         kfree(usblp);
1205 abort_ret:
1206         return retval;
1207 }
1208
1209 /*
1210  * We are a "new" style driver with usb_device_id table,
1211  * but our requirements are too intricate for simple match to handle.
1212  *
1213  * The "proto_bias" option may be used to specify the preferred protocol
1214  * for all USB printers (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
1215  * 3=USB_CLASS_PRINTER/1/3).  If the device supports the preferred protocol,
1216  * then we bind to it.
1217  *
1218  * The best interface for us is USB_CLASS_PRINTER/1/2, because it
1219  * is compatible with a stream of characters. If we find it, we bind to it.
1220  *
1221  * Note that the people from hpoj.sourceforge.net need to be able to
1222  * bind to USB_CLASS_PRINTER/1/3 (MLC/1284.4), so we provide them ioctls
1223  * for this purpose.
1224  *
1225  * Failing USB_CLASS_PRINTER/1/2, we look for USB_CLASS_PRINTER/1/3,
1226  * even though it's probably not stream-compatible, because this matches
1227  * the behaviour of the old code.
1228  *
1229  * If nothing else, we bind to USB_CLASS_PRINTER/1/1
1230  * - the unidirectional interface.
1231  */
1232 static int usblp_select_alts(struct usblp *usblp)
1233 {
1234         struct usb_interface *if_alt;
1235         struct usb_host_interface *ifd;
1236         struct usb_endpoint_descriptor *epwrite, *epread;
1237         int p, i;
1238         int res;
1239
1240         if_alt = usblp->intf;
1241
1242         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1243                 usblp->protocol[p].alt_setting = -1;
1244
1245         /* Find out what we have. */
1246         for (i = 0; i < if_alt->num_altsetting; i++) {
1247                 ifd = &if_alt->altsetting[i];
1248
1249                 if (ifd->desc.bInterfaceClass != USB_CLASS_PRINTER ||
1250                     ifd->desc.bInterfaceSubClass != 1)
1251                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1252                                 continue;
1253
1254                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1255                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1256                         continue;
1257
1258                 /* Look for the expected bulk endpoints. */
1259                 if (ifd->desc.bInterfaceProtocol > 1) {
1260                         res = usb_find_common_endpoints(ifd,
1261                                         &epread, &epwrite, NULL, NULL);
1262                 } else {
1263                         epread = NULL;
1264                         res = usb_find_bulk_out_endpoint(ifd, &epwrite);
1265                 }
1266
1267                 /* Ignore buggy hardware without the right endpoints. */
1268                 if (res)
1269                         continue;
1270
1271                 /* Turn off reads for buggy bidirectional printers. */
1272                 if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1273                         printk(KERN_INFO "usblp%d: Disabling reads from "
1274                             "problematic bidirectional printer\n",
1275                             usblp->minor);
1276                         epread = NULL;
1277                 }
1278
1279                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1280                                 ifd->desc.bAlternateSetting;
1281                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1282                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1283         }
1284
1285         /* If our requested protocol is supported, then use it. */
1286         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1287             proto_bias <= USBLP_LAST_PROTOCOL &&
1288             usblp->protocol[proto_bias].alt_setting != -1)
1289                 return proto_bias;
1290
1291         /* Ordering is important here. */
1292         if (usblp->protocol[2].alt_setting != -1)
1293                 return 2;
1294         if (usblp->protocol[1].alt_setting != -1)
1295                 return 1;
1296         if (usblp->protocol[3].alt_setting != -1)
1297                 return 3;
1298
1299         /* If nothing is available, then don't bind to this device. */
1300         return -1;
1301 }
1302
1303 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1304 {
1305         int r, alts;
1306
1307         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1308                 return -EINVAL;
1309
1310         alts = usblp->protocol[protocol].alt_setting;
1311         if (alts < 0)
1312                 return -EINVAL;
1313         r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1314         if (r < 0) {
1315                 printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1316                         alts, usblp->ifnum);
1317                 return r;
1318         }
1319
1320         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1321         usblp->current_protocol = protocol;
1322         dev_dbg(&usblp->intf->dev, "usblp%d set protocol %d\n",
1323                 usblp->minor, protocol);
1324         return 0;
1325 }
1326
1327 /* Retrieves and caches device ID string.
1328  * Returns length, including length bytes but not null terminator.
1329  * On error, returns a negative errno value. */
1330 static int usblp_cache_device_id_string(struct usblp *usblp)
1331 {
1332         int err, length;
1333
1334         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1335         if (err < 0) {
1336                 dev_dbg(&usblp->intf->dev,
1337                         "usblp%d: error = %d reading IEEE-1284 Device ID string\n",
1338                         usblp->minor, err);
1339                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1340                 return -EIO;
1341         }
1342
1343         /* First two bytes are length in big-endian.
1344          * They count themselves, and we copy them into
1345          * the user's buffer. */
1346         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1347         if (length < 2)
1348                 length = 2;
1349         else if (length >= USBLP_DEVICE_ID_SIZE)
1350                 length = USBLP_DEVICE_ID_SIZE - 1;
1351         usblp->device_id_string[length] = '\0';
1352
1353         dev_dbg(&usblp->intf->dev, "usblp%d Device ID string [len=%d]=\"%s\"\n",
1354                 usblp->minor, length, &usblp->device_id_string[2]);
1355
1356         return length;
1357 }
1358
1359 static void usblp_disconnect(struct usb_interface *intf)
1360 {
1361         struct usblp *usblp = usb_get_intfdata(intf);
1362
1363         usb_deregister_dev(intf, &usblp_class);
1364
1365         if (!usblp || !usblp->dev) {
1366                 dev_err(&intf->dev, "bogus disconnect\n");
1367                 BUG();
1368         }
1369
1370         mutex_lock(&usblp_mutex);
1371         mutex_lock(&usblp->mut);
1372         usblp->present = 0;
1373         wake_up(&usblp->wwait);
1374         wake_up(&usblp->rwait);
1375         usb_set_intfdata(intf, NULL);
1376
1377         usblp_unlink_urbs(usblp);
1378         mutex_unlock(&usblp->mut);
1379         usb_poison_anchored_urbs(&usblp->urbs);
1380
1381         if (!usblp->used)
1382                 usblp_cleanup(usblp);
1383
1384         mutex_unlock(&usblp_mutex);
1385 }
1386
1387 static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1388 {
1389         struct usblp *usblp = usb_get_intfdata(intf);
1390
1391         usblp_unlink_urbs(usblp);
1392 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1393         /* not strictly necessary, but just in case */
1394         wake_up(&usblp->wwait);
1395         wake_up(&usblp->rwait);
1396 #endif
1397
1398         return 0;
1399 }
1400
1401 static int usblp_resume(struct usb_interface *intf)
1402 {
1403         struct usblp *usblp = usb_get_intfdata(intf);
1404         int r;
1405
1406         r = handle_bidir(usblp);
1407
1408         return r;
1409 }
1410
1411 static const struct usb_device_id usblp_ids[] = {
1412         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 1) },
1413         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 2) },
1414         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 3) },
1415         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 1) },
1416         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 2) },
1417         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 3) },
1418         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1419         { }                                             /* Terminating entry */
1420 };
1421
1422 MODULE_DEVICE_TABLE(usb, usblp_ids);
1423
1424 static struct usb_driver usblp_driver = {
1425         .name =         "usblp",
1426         .probe =        usblp_probe,
1427         .disconnect =   usblp_disconnect,
1428         .suspend =      usblp_suspend,
1429         .resume =       usblp_resume,
1430         .id_table =     usblp_ids,
1431         .dev_groups =   usblp_groups,
1432         .supports_autosuspend = 1,
1433 };
1434
1435 module_usb_driver(usblp_driver);
1436
1437 MODULE_AUTHOR(DRIVER_AUTHOR);
1438 MODULE_DESCRIPTION(DRIVER_DESC);
1439 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1440 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1441 MODULE_LICENSE("GPL");