1/*
   2 * usblp.c
   3 *
   4 * Copyright (c) 1999 Michael Gee	<michael@linuxspecific.com>
   5 * Copyright (c) 1999 Pavel Machek	<pavel@ucw.cz>
   6 * Copyright (c) 2000 Randy Dunlap	<rdunlap@xenotime.net>
   7 * Copyright (c) 2000 Vojtech Pavlik	<vojtech@suse.cz>
   8 # Copyright (c) 2001 Pete Zaitcev	<zaitcev@redhat.com>
   9 # Copyright (c) 2001 David Paschal	<paschal@rcsis.com>
  10 * Copyright (c) 2006 Oliver Neukum	<oliver@neukum.name>
  11 *
  12 * USB Printer Device Class driver for USB printers and printer cables
  13 *
  14 * Sponsored by SuSE
  15 *
  16 * ChangeLog:
  17 *	v0.1 - thorough cleaning, URBification, almost a rewrite
  18 *	v0.2 - some more cleanups
  19 *	v0.3 - cleaner again, waitqueue fixes
  20 *	v0.4 - fixes in unidirectional mode
  21 *	v0.5 - add DEVICE_ID string support
  22 *	v0.6 - never time out
  23 *	v0.7 - fixed bulk-IN read and poll (David Paschal)
  24 *	v0.8 - add devfs support
  25 *	v0.9 - fix unplug-while-open paths
  26 *	v0.10- remove sleep_on, fix error on oom (oliver@neukum.org)
  27 *	v0.11 - add proto_bias option (Pete Zaitcev)
  28 *	v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
  29 *	v0.13 - alloc space for statusbuf (<status> not on stack);
  30 *		use usb_alloc_coherent() for read buf & write buf;
  31 *      none  - Maintained in Linux kernel after v0.13
  32 */
  33
  34/*
  35 * This program is free software; you can redistribute it and/or modify
  36 * it under the terms of the GNU General Public License as published by
  37 * the Free Software Foundation; either version 2 of the License, or
  38 * (at your option) any later version.
  39 *
  40 * This program is distributed in the hope that it will be useful,
  41 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  42 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  43 * GNU General Public License for more details.
  44 *
  45 * You should have received a copy of the GNU General Public License
  46 * along with this program; if not, write to the Free Software
  47 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  48 */
  49
  50#include <linux/module.h>
  51#include <linux/kernel.h>
  52#include <linux/sched.h>
  53#include <linux/signal.h>
  54#include <linux/poll.h>
  55#include <linux/slab.h>
  56#include <linux/lp.h>
  57#include <linux/mutex.h>
  58#undef DEBUG
  59#include <linux/usb.h>
  60#include <linux/usb/ch9.h>
  61#include <linux/ratelimit.h>
  62
  63/*
  64 * Version Information
  65 */
  66#define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
  67#define DRIVER_DESC "USB Printer Device Class driver"
  68
  69#define USBLP_BUF_SIZE		8192
  70#define USBLP_BUF_SIZE_IN	1024
  71#define USBLP_DEVICE_ID_SIZE	1024
  72
  73/* ioctls: */
  74#define IOCNR_GET_DEVICE_ID		1
  75#define IOCNR_GET_PROTOCOLS		2
  76#define IOCNR_SET_PROTOCOL		3
  77#define IOCNR_HP_SET_CHANNEL		4
  78#define IOCNR_GET_BUS_ADDRESS		5
  79#define IOCNR_GET_VID_PID		6
  80#define IOCNR_SOFT_RESET		7
  81/* Get device_id string: */
  82#define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
  83/* The following ioctls were added for http://hpoj.sourceforge.net:
  84 * Get two-int array:
  85 * [0]=current protocol
  86 *     (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
  87 *         3=USB_CLASS_PRINTER/1/3),
  88 * [1]=supported protocol mask (mask&(1<<n)!=0 means
  89 *     USB_CLASS_PRINTER/1/n supported):
  90 */
  91#define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
  92/*
  93 * Set protocol
  94 *     (arg: 1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
  95 *         3=USB_CLASS_PRINTER/1/3):
  96 */
  97#define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
  98/* Set channel number (HP Vendor-specific command): */
  99#define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
 100/* Get two-int array: [0]=bus number, [1]=device address: */
 101#define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
 102/* Get two-int array: [0]=vendor ID, [1]=product ID: */
 103#define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
 104/* Perform class specific soft reset */
 105#define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
 106
 107/*
 108 * A DEVICE_ID string may include the printer's serial number.
 109 * It should end with a semi-colon (';').
 110 * An example from an HP 970C DeskJet printer is (this is one long string,
 111 * with the serial number changed):
 112MFG: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:                    ;
 113 */
 114
 115/*
 116 * USB Printer Requests
 117 */
 118
 119#define USBLP_REQ_GET_ID			0x00
 120#define USBLP_REQ_GET_STATUS			0x01
 121#define USBLP_REQ_RESET				0x02
 122#define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST	0x00	/* HP Vendor-specific */
 123
 124#define USBLP_MINORS		16
 125#define USBLP_MINOR_BASE	0
 126
 127#define USBLP_CTL_TIMEOUT	5000			/* 5 seconds */
 128
 129#define USBLP_FIRST_PROTOCOL	1
 130#define USBLP_LAST_PROTOCOL	3
 131#define USBLP_MAX_PROTOCOLS	(USBLP_LAST_PROTOCOL+1)
 132
 133/*
 134 * some arbitrary status buffer size;
 135 * need a status buffer that is allocated via kmalloc(), not on stack
 136 */
 137#define STATUS_BUF_SIZE		8
 138
 139/*
 140 * Locks down the locking order:
 141 * ->wmut locks wstatus.
 142 * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
 143 * [rw]status. We only touch status when we know the side idle.
 144 * ->lock locks what interrupt accesses.
 145 */
 146struct usblp {
 147	struct usb_device	*dev;			/* USB device */
 148	struct mutex		wmut;
 149	struct mutex		mut;
 150	spinlock_t		lock;		/* locks rcomplete, wcomplete */
 151	char			*readbuf;		/* read transfer_buffer */
 152	char			*statusbuf;		/* status transfer_buffer */
 153	struct usb_anchor	urbs;
 154	wait_queue_head_t	rwait, wwait;
 155	int			readcount;		/* Counter for reads */
 156	int			ifnum;			/* Interface number */
 157	struct usb_interface	*intf;			/* The interface */
 158	/*
 159	 * Alternate-setting numbers and endpoints for each protocol
 160	 * (USB_CLASS_PRINTER/1/{index=1,2,3}) that the device supports:
 161	 */
 162	struct {
 163		int				alt_setting;
 164		struct usb_endpoint_descriptor	*epwrite;
 165		struct usb_endpoint_descriptor	*epread;
 166	}			protocol[USBLP_MAX_PROTOCOLS];
 167	int			current_protocol;
 168	int			minor;			/* minor number of device */
 169	int			wcomplete, rcomplete;
 170	int			wstatus;	/* bytes written or error */
 171	int			rstatus;	/* bytes ready or error */
 172	unsigned int		quirks;			/* quirks flags */
 173	unsigned int		flags;			/* mode flags */
 174	unsigned char		used;			/* True if open */
 175	unsigned char		present;		/* True if not disconnected */
 176	unsigned char		bidir;			/* interface is bidirectional */
 177	unsigned char		no_paper;		/* Paper Out happened */
 178	unsigned char		*device_id_string;	/* IEEE 1284 DEVICE ID string (ptr) */
 179							/* first 2 bytes are (big-endian) length */
 180};
 181
 182#ifdef DEBUG
 183static void usblp_dump(struct usblp *usblp)
 184{
 185	struct device *dev = &usblp->intf->dev;
 186	int p;
 187
 188	dev_dbg(dev, "usblp=0x%p\n", usblp);
 189	dev_dbg(dev, "dev=0x%p\n", usblp->dev);
 190	dev_dbg(dev, "present=%d\n", usblp->present);
 191	dev_dbg(dev, "readbuf=0x%p\n", usblp->readbuf);
 192	dev_dbg(dev, "readcount=%d\n", usblp->readcount);
 193	dev_dbg(dev, "ifnum=%d\n", usblp->ifnum);
 194	for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
 195		dev_dbg(dev, "protocol[%d].alt_setting=%d\n", p,
 196			usblp->protocol[p].alt_setting);
 197		dev_dbg(dev, "protocol[%d].epwrite=%p\n", p,
 198			usblp->protocol[p].epwrite);
 199		dev_dbg(dev, "protocol[%d].epread=%p\n", p,
 200			usblp->protocol[p].epread);
 201	}
 202	dev_dbg(dev, "current_protocol=%d\n", usblp->current_protocol);
 203	dev_dbg(dev, "minor=%d\n", usblp->minor);
 204	dev_dbg(dev, "wstatus=%d\n", usblp->wstatus);
 205	dev_dbg(dev, "rstatus=%d\n", usblp->rstatus);
 206	dev_dbg(dev, "quirks=%d\n", usblp->quirks);
 207	dev_dbg(dev, "used=%d\n", usblp->used);
 208	dev_dbg(dev, "bidir=%d\n", usblp->bidir);
 209	dev_dbg(dev, "device_id_string=\"%s\"\n",
 210		usblp->device_id_string ?
 211			usblp->device_id_string + 2 :
 212			(unsigned char *)"(null)");
 213}
 214#endif
 215
 216/* Quirks: various printer quirks are handled by this table & its flags. */
 217
 218struct quirk_printer_struct {
 219	__u16 vendorId;
 220	__u16 productId;
 221	unsigned int quirks;
 222};
 223
 224#define USBLP_QUIRK_BIDIR	0x1	/* reports bidir but requires unidirectional mode (no INs/reads) */
 225#define USBLP_QUIRK_USB_INIT	0x2	/* needs vendor USB init string */
 226#define USBLP_QUIRK_BAD_CLASS	0x4	/* descriptor uses vendor-specific Class or SubClass */
 227
 228static const struct quirk_printer_struct quirk_printers[] = {
 229	{ 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
 230	{ 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
 231	{ 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
 232	{ 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
 233	{ 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
 234	{ 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
 235	{ 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
 236	{ 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
 237	{ 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
 238	{ 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
 239	{ 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
 240	{ 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
 241	{ 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
 242	{ 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <kernel@zut.de> */
 243	{ 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
 244	{ 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
 245	{ 0, 0 }
 246};
 247
 248static int usblp_wwait(struct usblp *usblp, int nonblock);
 249static int usblp_wtest(struct usblp *usblp, int nonblock);
 250static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
 251static int usblp_rtest(struct usblp *usblp, int nonblock);
 252static int usblp_submit_read(struct usblp *usblp);
 253static int usblp_select_alts(struct usblp *usblp);
 254static int usblp_set_protocol(struct usblp *usblp, int protocol);
 255static int usblp_cache_device_id_string(struct usblp *usblp);
 256
 257/* forward reference to make our lives easier */
 258static struct usb_driver usblp_driver;
 259static DEFINE_MUTEX(usblp_mutex);	/* locks the existence of usblp's */
 260
 261/*
 262 * Functions for usblp control messages.
 263 */
 264
 265static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
 266{
 267	int retval;
 268	int index = usblp->ifnum;
 269
 270	/* High byte has the interface index.
 271	   Low byte has the alternate setting.
 272	 */
 273	if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS))
 274		index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
 275
 276	retval = usb_control_msg(usblp->dev,
 277		dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
 278		request, type | dir | recip, value, index, buf, len, USBLP_CTL_TIMEOUT);
 279	dev_dbg(&usblp->intf->dev,
 280		"usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d\n",
 281		request, !!dir, recip, value, index, len, retval);
 282	return retval < 0 ? retval : 0;
 283}
 284
 285#define usblp_read_status(usblp, status)\
 286	usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
 287#define usblp_get_id(usblp, config, id, maxlen)\
 288	usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
 289#define usblp_reset(usblp)\
 290	usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
 291
 292#define usblp_hp_channel_change_request(usblp, channel, buffer) \
 293	usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
 294
 295/*
 296 * See the description for usblp_select_alts() below for the usage
 297 * explanation.  Look into your /proc/bus/usb/devices and dmesg in
 298 * case of any trouble.
 299 */
 300static int proto_bias = -1;
 301
 302/*
 303 * URB callback.
 304 */
 305
 306static void usblp_bulk_read(struct urb *urb)
 307{
 308	struct usblp *usblp = urb->context;
 309	int status = urb->status;
 310
 311	if (usblp->present && usblp->used) {
 312		if (status)
 313			printk(KERN_WARNING "usblp%d: "
 314			    "nonzero read bulk status received: %d\n",
 315			    usblp->minor, status);
 316	}
 317	spin_lock(&usblp->lock);
 318	if (status < 0)
 319		usblp->rstatus = status;
 320	else
 321		usblp->rstatus = urb->actual_length;
 322	usblp->rcomplete = 1;
 323	wake_up(&usblp->rwait);
 324	spin_unlock(&usblp->lock);
 325
 326	usb_free_urb(urb);
 327}
 328
 329static void usblp_bulk_write(struct urb *urb)
 330{
 331	struct usblp *usblp = urb->context;
 332	int status = urb->status;
 333
 334	if (usblp->present && usblp->used) {
 335		if (status)
 336			printk(KERN_WARNING "usblp%d: "
 337			    "nonzero write bulk status received: %d\n",
 338			    usblp->minor, status);
 339	}
 340	spin_lock(&usblp->lock);
 341	if (status < 0)
 342		usblp->wstatus = status;
 343	else
 344		usblp->wstatus = urb->actual_length;
 345	usblp->no_paper = 0;
 346	usblp->wcomplete = 1;
 347	wake_up(&usblp->wwait);
 348	spin_unlock(&usblp->lock);
 349
 350	usb_free_urb(urb);
 351}
 352
 353/*
 354 * Get and print printer errors.
 355 */
 356
 357static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
 358
 359static int usblp_check_status(struct usblp *usblp, int err)
 360{
 361	unsigned char status, newerr = 0;
 362	int error;
 363
 364	mutex_lock(&usblp->mut);
 365	if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
 366		mutex_unlock(&usblp->mut);
 367		printk_ratelimited(KERN_ERR
 368				"usblp%d: error %d reading printer status\n",
 369				usblp->minor, error);
 370		return 0;
 371	}
 372	status = *usblp->statusbuf;
 373	mutex_unlock(&usblp->mut);
 374
 375	if (~status & LP_PERRORP)
 376		newerr = 3;
 377	if (status & LP_POUTPA)
 378		newerr = 1;
 379	if (~status & LP_PSELECD)
 380		newerr = 2;
 381
 382	if (newerr != err) {
 383		printk(KERN_INFO "usblp%d: %s\n",
 384		   usblp->minor, usblp_messages[newerr]);
 385	}
 386
 387	return newerr;
 388}
 389
 390static int handle_bidir(struct usblp *usblp)
 391{
 392	if (usblp->bidir && usblp->used) {
 393		if (usblp_submit_read(usblp) < 0)
 394			return -EIO;
 395	}
 396	return 0;
 397}
 398
 399/*
 400 * File op functions.
 401 */
 402
 403static int usblp_open(struct inode *inode, struct file *file)
 404{
 405	int minor = iminor(inode);
 406	struct usblp *usblp;
 407	struct usb_interface *intf;
 408	int retval;
 409
 410	if (minor < 0)
 411		return -ENODEV;
 412
 413	mutex_lock(&usblp_mutex);
 414
 415	retval = -ENODEV;
 416	intf = usb_find_interface(&usblp_driver, minor);
 417	if (!intf)
 418		goto out;
 419	usblp = usb_get_intfdata(intf);
 420	if (!usblp || !usblp->dev || !usblp->present)
 421		goto out;
 422
 423	retval = -EBUSY;
 424	if (usblp->used)
 425		goto out;
 426
 427	/*
 428	 * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
 429	 *  - We do not want persistent state which close(2) does not clear
 430	 *  - It is not used anyway, according to CUPS people
 431	 */
 432
 433	retval = usb_autopm_get_interface(intf);
 434	if (retval < 0)
 435		goto out;
 436	usblp->used = 1;
 437	file->private_data = usblp;
 438
 439	usblp->wcomplete = 1; /* we begin writeable */
 440	usblp->wstatus = 0;
 441	usblp->rcomplete = 0;
 442
 443	if (handle_bidir(usblp) < 0) {
 444		usb_autopm_put_interface(intf);
 445		usblp->used = 0;
 446		file->private_data = NULL;
 447		retval = -EIO;
 448	}
 449out:
 450	mutex_unlock(&usblp_mutex);
 451	return retval;
 452}
 453
 454static void usblp_cleanup(struct usblp *usblp)
 455{
 456	printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
 457
 458	kfree(usblp->readbuf);
 459	kfree(usblp->device_id_string);
 460	kfree(usblp->statusbuf);
 461	kfree(usblp);
 462}
 463
 464static void usblp_unlink_urbs(struct usblp *usblp)
 465{
 466	usb_kill_anchored_urbs(&usblp->urbs);
 467}
 468
 469static int usblp_release(struct inode *inode, struct file *file)
 470{
 471	struct usblp *usblp = file->private_data;
 472
 473	usblp->flags &= ~LP_ABORT;
 474
 475	mutex_lock(&usblp_mutex);
 476	usblp->used = 0;
 477	if (usblp->present) {
 478		usblp_unlink_urbs(usblp);
 479		usb_autopm_put_interface(usblp->intf);
 480	} else		/* finish cleanup from disconnect */
 481		usblp_cleanup(usblp);
 482	mutex_unlock(&usblp_mutex);
 483	return 0;
 484}
 485
 486/* No kernel lock - fine */
 487static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
 488{
 489	int ret;
 490	unsigned long flags;
 491
 492	struct usblp *usblp = file->private_data;
 493	/* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
 494	poll_wait(file, &usblp->rwait, wait);
 495	poll_wait(file, &usblp->wwait, wait);
 496	spin_lock_irqsave(&usblp->lock, flags);
 497	ret = ((usblp->bidir && usblp->rcomplete) ? POLLIN  | POLLRDNORM : 0) |
 498	   ((usblp->no_paper || usblp->wcomplete) ? POLLOUT | POLLWRNORM : 0);
 499	spin_unlock_irqrestore(&usblp->lock, flags);
 500	return ret;
 501}
 502
 503static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 504{
 505	struct usblp *usblp = file->private_data;
 506	int length, err, i;
 507	unsigned char newChannel;
 508	int status;
 509	int twoints[2];
 510	int retval = 0;
 511
 512	mutex_lock(&usblp->mut);
 513	if (!usblp->present) {
 514		retval = -ENODEV;
 515		goto done;
 516	}
 517
 518	dev_dbg(&usblp->intf->dev,
 519		"usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)\n", cmd,
 520		_IOC_TYPE(cmd), _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
 521
 522	if (_IOC_TYPE(cmd) == 'P')	/* new-style ioctl number */
 523
 524		switch (_IOC_NR(cmd)) {
 525
 526		case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
 527			if (_IOC_DIR(cmd) != _IOC_READ) {
 528				retval = -EINVAL;
 529				goto done;
 530			}
 531
 532			length = usblp_cache_device_id_string(usblp);
 533			if (length < 0) {
 534				retval = length;
 535				goto done;
 536			}
 537			if (length > _IOC_SIZE(cmd))
 538				length = _IOC_SIZE(cmd); /* truncate */
 539
 540			if (copy_to_user((void __user *) arg,
 541					usblp->device_id_string,
 542					(unsigned long) length)) {
 543				retval = -EFAULT;
 544				goto done;
 545			}
 546
 547			break;
 548
 549		case IOCNR_GET_PROTOCOLS:
 550			if (_IOC_DIR(cmd) != _IOC_READ ||
 551			    _IOC_SIZE(cmd) < sizeof(twoints)) {
 552				retval = -EINVAL;
 553				goto done;
 554			}
 555
 556			twoints[0] = usblp->current_protocol;
 557			twoints[1] = 0;
 558			for (i = USBLP_FIRST_PROTOCOL;
 559			     i <= USBLP_LAST_PROTOCOL; i++) {
 560				if (usblp->protocol[i].alt_setting >= 0)
 561					twoints[1] |= (1<<i);
 562			}
 563
 564			if (copy_to_user((void __user *)arg,
 565					(unsigned char *)twoints,
 566					sizeof(twoints))) {
 567				retval = -EFAULT;
 568				goto done;
 569			}
 570
 571			break;
 572
 573		case IOCNR_SET_PROTOCOL:
 574			if (_IOC_DIR(cmd) != _IOC_WRITE) {
 575				retval = -EINVAL;
 576				goto done;
 577			}
 578
 579#ifdef DEBUG
 580			if (arg == -10) {
 581				usblp_dump(usblp);
 582				break;
 583			}
 584#endif
 585
 586			usblp_unlink_urbs(usblp);
 587			retval = usblp_set_protocol(usblp, arg);
 588			if (retval < 0) {
 589				usblp_set_protocol(usblp,
 590					usblp->current_protocol);
 591			}
 592			break;
 593
 594		case IOCNR_HP_SET_CHANNEL:
 595			if (_IOC_DIR(cmd) != _IOC_WRITE ||
 596			    le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
 597			    usblp->quirks & USBLP_QUIRK_BIDIR) {
 598				retval = -EINVAL;
 599				goto done;
 600			}
 601
 602			err = usblp_hp_channel_change_request(usblp,
 603				arg, &newChannel);
 604			if (err < 0) {
 605				dev_err(&usblp->dev->dev,
 606					"usblp%d: error = %d setting "
 607					"HP channel\n",
 608					usblp->minor, err);
 609				retval = -EIO;
 610				goto done;
 611			}
 612
 613			dev_dbg(&usblp->intf->dev,
 614				"usblp%d requested/got HP channel %ld/%d\n",
 615				usblp->minor, arg, newChannel);
 616			break;
 617
 618		case IOCNR_GET_BUS_ADDRESS:
 619			if (_IOC_DIR(cmd) != _IOC_READ ||
 620			    _IOC_SIZE(cmd) < sizeof(twoints)) {
 621				retval = -EINVAL;
 622				goto done;
 623			}
 624
 625			twoints[0] = usblp->dev->bus->busnum;
 626			twoints[1] = usblp->dev->devnum;
 627			if (copy_to_user((void __user *)arg,
 628					(unsigned char *)twoints,
 629					sizeof(twoints))) {
 630				retval = -EFAULT;
 631				goto done;
 632			}
 633
 634			dev_dbg(&usblp->intf->dev,
 635				"usblp%d is bus=%d, device=%d\n",
 636				usblp->minor, twoints[0], twoints[1]);
 637			break;
 638
 639		case IOCNR_GET_VID_PID:
 640			if (_IOC_DIR(cmd) != _IOC_READ ||
 641			    _IOC_SIZE(cmd) < sizeof(twoints)) {
 642				retval = -EINVAL;
 643				goto done;
 644			}
 645
 646			twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
 647			twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
 648			if (copy_to_user((void __user *)arg,
 649					(unsigned char *)twoints,
 650					sizeof(twoints))) {
 651				retval = -EFAULT;
 652				goto done;
 653			}
 654
 655			dev_dbg(&usblp->intf->dev,
 656				"usblp%d is VID=0x%4.4X, PID=0x%4.4X\n",
 657				usblp->minor, twoints[0], twoints[1]);
 658			break;
 659
 660		case IOCNR_SOFT_RESET:
 661			if (_IOC_DIR(cmd) != _IOC_NONE) {
 662				retval = -EINVAL;
 663				goto done;
 664			}
 665			retval = usblp_reset(usblp);
 666			break;
 667		default:
 668			retval = -ENOTTY;
 669		}
 670	else	/* old-style ioctl value */
 671		switch (cmd) {
 672
 673		case LPGETSTATUS:
 674			retval = usblp_read_status(usblp, usblp->statusbuf);
 675			if (retval) {
 676				printk_ratelimited(KERN_ERR "usblp%d:"
 677					    "failed reading printer status (%d)\n",
 678					    usblp->minor, retval);
 679				retval = -EIO;
 680				goto done;
 681			}
 682			status = *usblp->statusbuf;
 683			if (copy_to_user((void __user *)arg, &status, sizeof(int)))
 684				retval = -EFAULT;
 685			break;
 686
 687		case LPABORT:
 688			if (arg)
 689				usblp->flags |= LP_ABORT;
 690			else
 691				usblp->flags &= ~LP_ABORT;
 692			break;
 693
 694		default:
 695			retval = -ENOTTY;
 696		}
 697
 698done:
 699	mutex_unlock(&usblp->mut);
 700	return retval;
 701}
 702
 703static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
 704{
 705	struct urb *urb;
 706	char *writebuf;
 707
 708	writebuf = kmalloc(transfer_length, GFP_KERNEL);
 709	if (writebuf == NULL)
 710		return NULL;
 711	urb = usb_alloc_urb(0, GFP_KERNEL);
 712	if (urb == NULL) {
 713		kfree(writebuf);
 714		return NULL;
 715	}
 716
 717	usb_fill_bulk_urb(urb, usblp->dev,
 718		usb_sndbulkpipe(usblp->dev,
 719		 usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
 720		writebuf, transfer_length, usblp_bulk_write, usblp);
 721	urb->transfer_flags |= URB_FREE_BUFFER;
 722
 723	return urb;
 724}
 725
 726static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 727{
 728	struct usblp *usblp = file->private_data;
 729	struct urb *writeurb;
 730	int rv;
 731	int transfer_length;
 732	ssize_t writecount = 0;
 733
 734	if (mutex_lock_interruptible(&usblp->wmut)) {
 735		rv = -EINTR;
 736		goto raise_biglock;
 737	}
 738	if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
 739		goto raise_wait;
 740
 741	while (writecount < count) {
 742		/*
 743		 * Step 1: Submit next block.
 744		 */
 745		if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
 746			transfer_length = USBLP_BUF_SIZE;
 747
 748		rv = -ENOMEM;
 749		writeurb = usblp_new_writeurb(usblp, transfer_length);
 750		if (writeurb == NULL)
 751			goto raise_urb;
 752		usb_anchor_urb(writeurb, &usblp->urbs);
 753
 754		if (copy_from_user(writeurb->transfer_buffer,
 755				   buffer + writecount, transfer_length)) {
 756			rv = -EFAULT;
 757			goto raise_badaddr;
 758		}
 759
 760		spin_lock_irq(&usblp->lock);
 761		usblp->wcomplete = 0;
 762		spin_unlock_irq(&usblp->lock);
 763		if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
 764			usblp->wstatus = 0;
 765			spin_lock_irq(&usblp->lock);
 766			usblp->no_paper = 0;
 767			usblp->wcomplete = 1;
 768			wake_up(&usblp->wwait);
 769			spin_unlock_irq(&usblp->lock);
 770			if (rv != -ENOMEM)
 771				rv = -EIO;
 772			goto raise_submit;
 773		}
 774
 775		/*
 776		 * Step 2: Wait for transfer to end, collect results.
 777		 */
 778		rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
 779		if (rv < 0) {
 780			if (rv == -EAGAIN) {
 781				/* Presume that it's going to complete well. */
 782				writecount += transfer_length;
 783			}
 784			if (rv == -ENOSPC) {
 785				spin_lock_irq(&usblp->lock);
 786				usblp->no_paper = 1;	/* Mark for poll(2) */
 787				spin_unlock_irq(&usblp->lock);
 788				writecount += transfer_length;
 789			}
 790			/* Leave URB dangling, to be cleaned on close. */
 791			goto collect_error;
 792		}
 793
 794		if (usblp->wstatus < 0) {
 795			rv = -EIO;
 796			goto collect_error;
 797		}
 798		/*
 799		 * This is critical: it must be our URB, not other writer's.
 800		 * The wmut exists mainly to cover us here.
 801		 */
 802		writecount += usblp->wstatus;
 803	}
 804
 805	mutex_unlock(&usblp->wmut);
 806	return writecount;
 807
 808raise_submit:
 809raise_badaddr:
 810	usb_unanchor_urb(writeurb);
 811	usb_free_urb(writeurb);
 812raise_urb:
 813raise_wait:
 814collect_error:		/* Out of raise sequence */
 815	mutex_unlock(&usblp->wmut);
 816raise_biglock:
 817	return writecount ? writecount : rv;
 818}
 819
 820/*
 821 * Notice that we fail to restart in a few cases: on EFAULT, on restart
 822 * error, etc. This is the historical behaviour. In all such cases we return
 823 * EIO, and applications loop in order to get the new read going.
 824 */
 825static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
 826{
 827	struct usblp *usblp = file->private_data;
 828	ssize_t count;
 829	ssize_t avail;
 830	int rv;
 831
 832	if (!usblp->bidir)
 833		return -EINVAL;
 834
 835	rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
 836	if (rv < 0)
 837		return rv;
 838
 839	if ((avail = usblp->rstatus) < 0) {
 840		printk(KERN_ERR "usblp%d: error %d reading from printer\n",
 841		    usblp->minor, (int)avail);
 842		usblp_submit_read(usblp);
 843		count = -EIO;
 844		goto done;
 845	}
 846
 847	count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
 848	if (count != 0 &&
 849	    copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
 850		count = -EFAULT;
 851		goto done;
 852	}
 853
 854	if ((usblp->readcount += count) == avail) {
 855		if (usblp_submit_read(usblp) < 0) {
 856			/* We don't want to leak USB return codes into errno. */
 857			if (count == 0)
 858				count = -EIO;
 859			goto done;
 860		}
 861	}
 862
 863done:
 864	mutex_unlock(&usblp->mut);
 865	return count;
 866}
 867
 868/*
 869 * Wait for the write path to come idle.
 870 * This is called under the ->wmut, so the idle path stays idle.
 871 *
 872 * Our write path has a peculiar property: it does not buffer like a tty,
 873 * but waits for the write to succeed. This allows our ->release to bug out
 874 * without waiting for writes to drain. But it obviously does not work
 875 * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
 876 * select(2) or poll(2) to wait for the buffer to drain before closing.
 877 * Alternatively, set blocking mode with fcntl and issue a zero-size write.
 878 */
 879static int usblp_wwait(struct usblp *usblp, int nonblock)
 880{
 881	DECLARE_WAITQUEUE(waita, current);
 882	int rc;
 883	int err = 0;
 884
 885	add_wait_queue(&usblp->wwait, &waita);
 886	for (;;) {
 887		if (mutex_lock_interruptible(&usblp->mut)) {
 888			rc = -EINTR;
 889			break;
 890		}
 891		set_current_state(TASK_INTERRUPTIBLE);
 892		rc = usblp_wtest(usblp, nonblock);
 893		mutex_unlock(&usblp->mut);
 894		if (rc <= 0)
 895			break;
 896
 897		if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
 898			if (usblp->flags & LP_ABORT) {
 899				err = usblp_check_status(usblp, err);
 900				if (err == 1) {	/* Paper out */
 901					rc = -ENOSPC;
 902					break;
 903				}
 904			} else {
 905				/* Prod the printer, Gentoo#251237. */
 906				mutex_lock(&usblp->mut);
 907				usblp_read_status(usblp, usblp->statusbuf);
 908				mutex_unlock(&usblp->mut);
 909			}
 910		}
 911	}
 912	set_current_state(TASK_RUNNING);
 913	remove_wait_queue(&usblp->wwait, &waita);
 914	return rc;
 915}
 916
 917static int usblp_wtest(struct usblp *usblp, int nonblock)
 918{
 919	unsigned long flags;
 920
 921	if (!usblp->present)
 922		return -ENODEV;
 923	if (signal_pending(current))
 924		return -EINTR;
 925	spin_lock_irqsave(&usblp->lock, flags);
 926	if (usblp->wcomplete) {
 927		spin_unlock_irqrestore(&usblp->lock, flags);
 928		return 0;
 929	}
 930	spin_unlock_irqrestore(&usblp->lock, flags);
 931	if (nonblock)
 932		return -EAGAIN;
 933	return 1;
 934}
 935
 936/*
 937 * Wait for read bytes to become available. This probably should have been
 938 * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
 939 * name for functions which lock and return.
 940 *
 941 * We do not use wait_event_interruptible because it makes locking iffy.
 942 */
 943static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
 944{
 945	DECLARE_WAITQUEUE(waita, current);
 946	int rc;
 947
 948	add_wait_queue(&usblp->rwait, &waita);
 949	for (;;) {
 950		if (mutex_lock_interruptible(&usblp->mut)) {
 951			rc = -EINTR;
 952			break;
 953		}
 954		set_current_state(TASK_INTERRUPTIBLE);
 955		if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
 956			mutex_unlock(&usblp->mut);
 957			break;
 958		}
 959		if (rc == 0)	/* Keep it locked */
 960			break;
 961		mutex_unlock(&usblp->mut);
 962		schedule();
 963	}
 964	set_current_state(TASK_RUNNING);
 965	remove_wait_queue(&usblp->rwait, &waita);
 966	return rc;
 967}
 968
 969static int usblp_rtest(struct usblp *usblp, int nonblock)
 970{
 971	unsigned long flags;
 972
 973	if (!usblp->present)
 974		return -ENODEV;
 975	if (signal_pending(current))
 976		return -EINTR;
 977	spin_lock_irqsave(&usblp->lock, flags);
 978	if (usblp->rcomplete) {
 979		spin_unlock_irqrestore(&usblp->lock, flags);
 980		return 0;
 981	}
 982	spin_unlock_irqrestore(&usblp->lock, flags);
 983	if (nonblock)
 984		return -EAGAIN;
 985	return 1;
 986}
 987
 988/*
 989 * Please check ->bidir and other such things outside for now.
 990 */
 991static int usblp_submit_read(struct usblp *usblp)
 992{
 993	struct urb *urb;
 994	unsigned long flags;
 995	int rc;
 996
 997	rc = -ENOMEM;
 998	urb = usb_alloc_urb(0, GFP_KERNEL);
 999	if (urb == NULL)
1000		goto raise_urb;
1001
1002	usb_fill_bulk_urb(urb, usblp->dev,
1003		usb_rcvbulkpipe(usblp->dev,
1004		  usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
1005		usblp->readbuf, USBLP_BUF_SIZE_IN,
1006		usblp_bulk_read, usblp);
1007	usb_anchor_urb(urb, &usblp->urbs);
1008
1009	spin_lock_irqsave(&usblp->lock, flags);
1010	usblp->readcount = 0; /* XXX Why here? */
1011	usblp->rcomplete = 0;
1012	spin_unlock_irqrestore(&usblp->lock, flags);
1013	if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
1014		dev_dbg(&usblp->intf->dev, "error submitting urb (%d)\n", rc);
1015		spin_lock_irqsave(&usblp->lock, flags);
1016		usblp->rstatus = rc;
1017		usblp->rcomplete = 1;
1018		spin_unlock_irqrestore(&usblp->lock, flags);
1019		goto raise_submit;
1020	}
1021
1022	return 0;
1023
1024raise_submit:
1025	usb_unanchor_urb(urb);
1026	usb_free_urb(urb);
1027raise_urb:
1028	return rc;
1029}
1030
1031/*
1032 * Checks for printers that have quirks, such as requiring unidirectional
1033 * communication but reporting bidirectional; currently some HP printers
1034 * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1035 * sent at each open (like some Epsons).
1036 * Returns 1 if found, 0 if not found.
1037 *
1038 * HP recommended that we use the bidirectional interface but
1039 * don't attempt any bulk IN transfers from the IN endpoint.
1040 * Here's some more detail on the problem:
1041 * The problem is not that it isn't bidirectional though. The problem
1042 * is that if you request a device ID, or status information, while
1043 * the buffers are full, the return data will end up in the print data
1044 * buffer. For example if you make sure you never request the device ID
1045 * while you are sending print data, and you don't try to query the
1046 * printer status every couple of milliseconds, you will probably be OK.
1047 */
1048static unsigned int usblp_quirks(__u16 vendor, __u16 product)
1049{
1050	int i;
1051
1052	for (i = 0; quirk_printers[i].vendorId; i++) {
1053		if (vendor == quirk_printers[i].vendorId &&
1054		    product == quirk_printers[i].productId)
1055			return quirk_printers[i].quirks;
1056	}
1057	return 0;
1058}
1059
1060static const struct file_operations usblp_fops = {
1061	.owner =	THIS_MODULE,
1062	.read =		usblp_read,
1063	.write =	usblp_write,
1064	.poll =		usblp_poll,
1065	.unlocked_ioctl =	usblp_ioctl,
1066	.compat_ioctl =		usblp_ioctl,
1067	.open =		usblp_open,
1068	.release =	usblp_release,
1069	.llseek =	noop_llseek,
1070};
1071
1072static char *usblp_devnode(struct device *dev, umode_t *mode)
1073{
1074	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1075}
1076
1077static struct usb_class_driver usblp_class = {
1078	.name =		"lp%d",
1079	.devnode =	usblp_devnode,
1080	.fops =		&usblp_fops,
1081	.minor_base =	USBLP_MINOR_BASE,
1082};
1083
1084static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
1085{
1086	struct usb_interface *intf = to_usb_interface(dev);
1087	struct usblp *usblp = usb_get_intfdata(intf);
1088
1089	if (usblp->device_id_string[0] == 0 &&
1090	    usblp->device_id_string[1] == 0)
1091		return 0;
1092
1093	return sprintf(buf, "%s", usblp->device_id_string+2);
1094}
1095
1096static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
1097
1098static int usblp_probe(struct usb_interface *intf,
1099		       const struct usb_device_id *id)
1100{
1101	struct usb_device *dev = interface_to_usbdev(intf);
1102	struct usblp *usblp;
1103	int protocol;
1104	int retval;
1105
1106	/* Malloc and start initializing usblp structure so we can use it
1107	 * directly. */
1108	usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1109	if (!usblp) {
1110		retval = -ENOMEM;
1111		goto abort_ret;
1112	}
1113	usblp->dev = dev;
1114	mutex_init(&usblp->wmut);
1115	mutex_init(&usblp->mut);
1116	spin_lock_init(&usblp->lock);
1117	init_waitqueue_head(&usblp->rwait);
1118	init_waitqueue_head(&usblp->wwait);
1119	init_usb_anchor(&usblp->urbs);
1120	usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1121	usblp->intf = intf;
1122
1123	/* Malloc device ID string buffer to the largest expected length,
1124	 * since we can re-query it on an ioctl and a dynamic string
1125	 * could change in length. */
1126	if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1127		retval = -ENOMEM;
1128		goto abort;
1129	}
1130
1131	/*
1132	 * Allocate read buffer. We somewhat wastefully
1133	 * malloc both regardless of bidirectionality, because the
1134	 * alternate setting can be changed later via an ioctl.
1135	 */
1136	if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1137		retval = -ENOMEM;
1138		goto abort;
1139	}
1140
1141	/* Allocate buffer for printer status */
1142	usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1143	if (!usblp->statusbuf) {
1144		retval = -ENOMEM;
1145		goto abort;
1146	}
1147
1148	/* Lookup quirks for this printer. */
1149	usblp->quirks = usblp_quirks(
1150		le16_to_cpu(dev->descriptor.idVendor),
1151		le16_to_cpu(dev->descriptor.idProduct));
1152
1153	/* Analyze and pick initial alternate settings and endpoints. */
1154	protocol = usblp_select_alts(usblp);
1155	if (protocol < 0) {
1156		dev_dbg(&intf->dev,
1157			"incompatible printer-class device 0x%4.4X/0x%4.4X\n",
1158			le16_to_cpu(dev->descriptor.idVendor),
1159			le16_to_cpu(dev->descriptor.idProduct));
1160		retval = -ENODEV;
1161		goto abort;
1162	}
1163
1164	/* Setup the selected alternate setting and endpoints. */
1165	if (usblp_set_protocol(usblp, protocol) < 0) {
1166		retval = -ENODEV;	/* ->probe isn't ->ioctl */
1167		goto abort;
1168	}
1169
1170	/* Retrieve and store the device ID string. */
1171	usblp_cache_device_id_string(usblp);
1172	retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1173	if (retval)
1174		goto abort_intfdata;
1175
1176#ifdef DEBUG
1177	usblp_check_status(usblp, 0);
1178#endif
1179
1180	usb_set_intfdata(intf, usblp);
1181
1182	usblp->present = 1;
1183
1184	retval = usb_register_dev(intf, &usblp_class);
1185	if (retval) {
1186		dev_err(&intf->dev,
1187			"usblp: Not able to get a minor (base %u, slice default): %d\n",
1188			USBLP_MINOR_BASE, retval);
1189		goto abort_intfdata;
1190	}
1191	usblp->minor = intf->minor;
1192	dev_info(&intf->dev,
1193		"usblp%d: USB %sdirectional printer dev %d if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1194		usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1195		usblp->ifnum,
1196		usblp->protocol[usblp->current_protocol].alt_setting,
1197		usblp->current_protocol,
1198		le16_to_cpu(usblp->dev->descriptor.idVendor),
1199		le16_to_cpu(usblp->dev->descriptor.idProduct));
1200
1201	return 0;
1202
1203abort_intfdata:
1204	usb_set_intfdata(intf, NULL);
1205	device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1206abort:
1207	kfree(usblp->readbuf);
1208	kfree(usblp->statusbuf);
1209	kfree(usblp->device_id_string);
1210	kfree(usblp);
1211abort_ret:
1212	return retval;
1213}
1214
1215/*
1216 * We are a "new" style driver with usb_device_id table,
1217 * but our requirements are too intricate for simple match to handle.
1218 *
1219 * The "proto_bias" option may be used to specify the preferred protocol
1220 * for all USB printers (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
1221 * 3=USB_CLASS_PRINTER/1/3).  If the device supports the preferred protocol,
1222 * then we bind to it.
1223 *
1224 * The best interface for us is USB_CLASS_PRINTER/1/2, because it
1225 * is compatible with a stream of characters. If we find it, we bind to it.
1226 *
1227 * Note that the people from hpoj.sourceforge.net need to be able to
1228 * bind to USB_CLASS_PRINTER/1/3 (MLC/1284.4), so we provide them ioctls
1229 * for this purpose.
1230 *
1231 * Failing USB_CLASS_PRINTER/1/2, we look for USB_CLASS_PRINTER/1/3,
1232 * even though it's probably not stream-compatible, because this matches
1233 * the behaviour of the old code.
1234 *
1235 * If nothing else, we bind to USB_CLASS_PRINTER/1/1
1236 * - the unidirectional interface.
1237 */
1238static int usblp_select_alts(struct usblp *usblp)
1239{
1240	struct usb_interface *if_alt;
1241	struct usb_host_interface *ifd;
1242	struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1243	int p, i, e;
1244
1245	if_alt = usblp->intf;
1246
1247	for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1248		usblp->protocol[p].alt_setting = -1;
1249
1250	/* Find out what we have. */
1251	for (i = 0; i < if_alt->num_altsetting; i++) {
1252		ifd = &if_alt->altsetting[i];
1253
1254		if (ifd->desc.bInterfaceClass != USB_CLASS_PRINTER ||
1255		    ifd->desc.bInterfaceSubClass != 1)
1256			if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1257				continue;
1258
1259		if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1260		    ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1261			continue;
1262
1263		/* Look for bulk OUT and IN endpoints. */
1264		epwrite = epread = NULL;
1265		for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1266			epd = &ifd->endpoint[e].desc;
1267
1268			if (usb_endpoint_is_bulk_out(epd))
1269				if (!epwrite)
1270					epwrite = epd;
1271
1272			if (usb_endpoint_is_bulk_in(epd))
1273				if (!epread)
1274					epread = epd;
1275		}
1276
1277		/* Ignore buggy hardware without the right endpoints. */
1278		if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1279			continue;
1280
1281		/*
1282		 * Turn off reads for USB_CLASS_PRINTER/1/1 (unidirectional)
1283		 * interfaces and buggy bidirectional printers.
1284		 */
1285		if (ifd->desc.bInterfaceProtocol == 1) {
1286			epread = NULL;
1287		} else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1288			printk(KERN_INFO "usblp%d: Disabling reads from "
1289			    "problematic bidirectional printer\n",
1290			    usblp->minor);
1291			epread = NULL;
1292		}
1293
1294		usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1295				ifd->desc.bAlternateSetting;
1296		usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1297		usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1298	}
1299
1300	/* If our requested protocol is supported, then use it. */
1301	if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1302	    proto_bias <= USBLP_LAST_PROTOCOL &&
1303	    usblp->protocol[proto_bias].alt_setting != -1)
1304		return proto_bias;
1305
1306	/* Ordering is important here. */
1307	if (usblp->protocol[2].alt_setting != -1)
1308		return 2;
1309	if (usblp->protocol[1].alt_setting != -1)
1310		return 1;
1311	if (usblp->protocol[3].alt_setting != -1)
1312		return 3;
1313
1314	/* If nothing is available, then don't bind to this device. */
1315	return -1;
1316}
1317
1318static int usblp_set_protocol(struct usblp *usblp, int protocol)
1319{
1320	int r, alts;
1321
1322	if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1323		return -EINVAL;
1324
1325	alts = usblp->protocol[protocol].alt_setting;
1326	if (alts < 0)
1327		return -EINVAL;
1328	r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1329	if (r < 0) {
1330		printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1331			alts, usblp->ifnum);
1332		return r;
1333	}
1334
1335	usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1336	usblp->current_protocol = protocol;
1337	dev_dbg(&usblp->intf->dev, "usblp%d set protocol %d\n",
1338		usblp->minor, protocol);
1339	return 0;
1340}
1341
1342/* Retrieves and caches device ID string.
1343 * Returns length, including length bytes but not null terminator.
1344 * On error, returns a negative errno value. */
1345static int usblp_cache_device_id_string(struct usblp *usblp)
1346{
1347	int err, length;
1348
1349	err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1350	if (err < 0) {
1351		dev_dbg(&usblp->intf->dev,
1352			"usblp%d: error = %d reading IEEE-1284 Device ID string\n",
1353			usblp->minor, err);
1354		usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1355		return -EIO;
1356	}
1357
1358	/* First two bytes are length in big-endian.
1359	 * They count themselves, and we copy them into
1360	 * the user's buffer. */
1361	length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1362	if (length < 2)
1363		length = 2;
1364	else if (length >= USBLP_DEVICE_ID_SIZE)
1365		length = USBLP_DEVICE_ID_SIZE - 1;
1366	usblp->device_id_string[length] = '\0';
1367
1368	dev_dbg(&usblp->intf->dev, "usblp%d Device ID string [len=%d]=\"%s\"\n",
1369		usblp->minor, length, &usblp->device_id_string[2]);
1370
1371	return length;
1372}
1373
1374static void usblp_disconnect(struct usb_interface *intf)
1375{
1376	struct usblp *usblp = usb_get_intfdata(intf);
1377
1378	usb_deregister_dev(intf, &usblp_class);
1379
1380	if (!usblp || !usblp->dev) {
1381		dev_err(&intf->dev, "bogus disconnect\n");
1382		BUG();
1383	}
1384
1385	device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1386
1387	mutex_lock(&usblp_mutex);
1388	mutex_lock(&usblp->mut);
1389	usblp->present = 0;
1390	wake_up(&usblp->wwait);
1391	wake_up(&usblp->rwait);
1392	usb_set_intfdata(intf, NULL);
1393
1394	usblp_unlink_urbs(usblp);
1395	mutex_unlock(&usblp->mut);
1396
1397	if (!usblp->used)
1398		usblp_cleanup(usblp);
1399	mutex_unlock(&usblp_mutex);
1400}
1401
1402static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1403{
1404	struct usblp *usblp = usb_get_intfdata(intf);
1405
1406	usblp_unlink_urbs(usblp);
1407#if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1408	/* not strictly necessary, but just in case */
1409	wake_up(&usblp->wwait);
1410	wake_up(&usblp->rwait);
1411#endif
1412
1413	return 0;
1414}
1415
1416static int usblp_resume(struct usb_interface *intf)
1417{
1418	struct usblp *usblp = usb_get_intfdata(intf);
1419	int r;
1420
1421	r = handle_bidir(usblp);
1422
1423	return r;
1424}
1425
1426static const struct usb_device_id usblp_ids[] = {
1427	{ USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 1) },
1428	{ USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 2) },
1429	{ USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 3) },
1430	{ USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 1) },
1431	{ USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 2) },
1432	{ USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 3) },
1433	{ USB_DEVICE(0x04b8, 0x0202) },	/* Seiko Epson Receipt Printer M129C */
1434	{ }						/* Terminating entry */
1435};
1436
1437MODULE_DEVICE_TABLE(usb, usblp_ids);
1438
1439static struct usb_driver usblp_driver = {
1440	.name =		"usblp",
1441	.probe =	usblp_probe,
1442	.disconnect =	usblp_disconnect,
1443	.suspend =	usblp_suspend,
1444	.resume =	usblp_resume,
1445	.id_table =	usblp_ids,
1446	.supports_autosuspend =	1,
1447};
1448
1449module_usb_driver(usblp_driver);
1450
1451MODULE_AUTHOR(DRIVER_AUTHOR);
1452MODULE_DESCRIPTION(DRIVER_DESC);
1453module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1454MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1455MODULE_LICENSE("GPL");