1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * usblp.c
   4 *
   5 * Copyright (c) 1999 Michael Gee	<michael@linuxspecific.com>
   6 * Copyright (c) 1999 Pavel Machek	<pavel@ucw.cz>
   7 * Copyright (c) 2000 Randy Dunlap	<rdunlap@xenotime.net>
   8 * Copyright (c) 2000 Vojtech Pavlik	<vojtech@suse.cz>
   9 # Copyright (c) 2001 Pete Zaitcev	<zaitcev@redhat.com>
  10 # Copyright (c) 2001 David Paschal	<paschal@rcsis.com>
  11 * Copyright (c) 2006 Oliver Neukum	<oliver@neukum.name>
  12 *
  13 * USB Printer Device Class driver for USB printers and printer cables
  14 *
  15 * Sponsored by SuSE
  16 *
  17 * ChangeLog:
  18 *	v0.1 - thorough cleaning, URBification, almost a rewrite
  19 *	v0.2 - some more cleanups
  20 *	v0.3 - cleaner again, waitqueue fixes
  21 *	v0.4 - fixes in unidirectional mode
  22 *	v0.5 - add DEVICE_ID string support
  23 *	v0.6 - never time out
  24 *	v0.7 - fixed bulk-IN read and poll (David Paschal)
  25 *	v0.8 - add devfs support
  26 *	v0.9 - fix unplug-while-open paths
  27 *	v0.10- remove sleep_on, fix error on oom (oliver@neukum.org)
  28 *	v0.11 - add proto_bias option (Pete Zaitcev)
  29 *	v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
  30 *	v0.13 - alloc space for statusbuf (<status> not on stack);
  31 *		use usb_alloc_coherent() for read buf & write buf;
  32 *      none  - Maintained in Linux kernel after v0.13
  33 */
  34
  35#include <linux/module.h>
  36#include <linux/kernel.h>
  37#include <linux/sched/signal.h>
  38#include <linux/signal.h>
  39#include <linux/poll.h>
  40#include <linux/slab.h>
  41#include <linux/lp.h>
  42#include <linux/mutex.h>
  43#undef DEBUG
  44#include <linux/usb.h>
  45#include <linux/usb/ch9.h>
  46#include <linux/ratelimit.h>
  47
  48/*
  49 * Version Information
  50 */
  51#define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
  52#define DRIVER_DESC "USB Printer Device Class driver"
  53
  54#define USBLP_BUF_SIZE		8192
  55#define USBLP_BUF_SIZE_IN	1024
  56#define USBLP_DEVICE_ID_SIZE	1024
  57
  58/* ioctls: */
  59#define IOCNR_GET_DEVICE_ID		1
  60#define IOCNR_GET_PROTOCOLS		2
  61#define IOCNR_SET_PROTOCOL		3
  62#define IOCNR_HP_SET_CHANNEL		4
  63#define IOCNR_GET_BUS_ADDRESS		5
  64#define IOCNR_GET_VID_PID		6
  65#define IOCNR_SOFT_RESET		7
  66/* Get device_id string: */
  67#define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
  68/* The following ioctls were added for http://hpoj.sourceforge.net:
  69 * Get two-int array:
  70 * [0]=current protocol
  71 *     (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
  72 *         3=USB_CLASS_PRINTER/1/3),
  73 * [1]=supported protocol mask (mask&(1<<n)!=0 means
  74 *     USB_CLASS_PRINTER/1/n supported):
  75 */
  76#define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
  77/*
  78 * Set protocol
  79 *     (arg: 1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
  80 *         3=USB_CLASS_PRINTER/1/3):
  81 */
  82#define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
  83/* Set channel number (HP Vendor-specific command): */
  84#define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
  85/* Get two-int array: [0]=bus number, [1]=device address: */
  86#define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
  87/* Get two-int array: [0]=vendor ID, [1]=product ID: */
  88#define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
  89/* Perform class specific soft reset */
  90#define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
  91
  92/*
  93 * A DEVICE_ID string may include the printer's serial number.
  94 * It should end with a semi-colon (';').
  95 * An example from an HP 970C DeskJet printer is (this is one long string,
  96 * with the serial number changed):
  97MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:Hewlett-Packard DeskJet 970C;SERN:US970CSEPROF;VSTATUS:$HB0$NC0,ff,DN,IDLE,CUT,K1,C0,DP,NR,KP000,CP027;VP:0800,FL,B0;VJ:                    ;
  98 */
  99
 100/*
 101 * USB Printer Requests
 102 */
 103
 104#define USBLP_REQ_GET_ID			0x00
 105#define USBLP_REQ_GET_STATUS			0x01
 106#define USBLP_REQ_RESET				0x02
 107#define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST	0x00	/* HP Vendor-specific */
 108
 109#define USBLP_MINORS		16
 110#define USBLP_MINOR_BASE	0
 111
 112#define USBLP_CTL_TIMEOUT	5000			/* 5 seconds */
 113
 114#define USBLP_FIRST_PROTOCOL	1
 115#define USBLP_LAST_PROTOCOL	3
 116#define USBLP_MAX_PROTOCOLS	(USBLP_LAST_PROTOCOL+1)
 117
 118/*
 119 * some arbitrary status buffer size;
 120 * need a status buffer that is allocated via kmalloc(), not on stack
 121 */
 122#define STATUS_BUF_SIZE		8
 123
 124/*
 125 * Locks down the locking order:
 126 * ->wmut locks wstatus.
 127 * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
 128 * [rw]status. We only touch status when we know the side idle.
 129 * ->lock locks what interrupt accesses.
 130 */
 131struct usblp {
 132	struct usb_device	*dev;			/* USB device */
 133	struct mutex		wmut;
 134	struct mutex		mut;
 135	spinlock_t		lock;		/* locks rcomplete, wcomplete */
 136	char			*readbuf;		/* read transfer_buffer */
 137	char			*statusbuf;		/* status transfer_buffer */
 138	struct usb_anchor	urbs;
 139	wait_queue_head_t	rwait, wwait;
 140	int			readcount;		/* Counter for reads */
 141	int			ifnum;			/* Interface number */
 142	struct usb_interface	*intf;			/* The interface */
 143	/*
 144	 * Alternate-setting numbers and endpoints for each protocol
 145	 * (USB_CLASS_PRINTER/1/{index=1,2,3}) that the device supports:
 146	 */
 147	struct {
 148		int				alt_setting;
 149		struct usb_endpoint_descriptor	*epwrite;
 150		struct usb_endpoint_descriptor	*epread;
 151	}			protocol[USBLP_MAX_PROTOCOLS];
 152	int			current_protocol;
 153	int			minor;			/* minor number of device */
 154	int			wcomplete, rcomplete;
 155	int			wstatus;	/* bytes written or error */
 156	int			rstatus;	/* bytes ready or error */
 157	unsigned int		quirks;			/* quirks flags */
 158	unsigned int		flags;			/* mode flags */
 159	unsigned char		used;			/* True if open */
 160	unsigned char		present;		/* True if not disconnected */
 161	unsigned char		bidir;			/* interface is bidirectional */
 162	unsigned char		no_paper;		/* Paper Out happened */
 163	unsigned char		*device_id_string;	/* IEEE 1284 DEVICE ID string (ptr) */
 164							/* first 2 bytes are (big-endian) length */
 165};
 166
 167#ifdef DEBUG
 168static void usblp_dump(struct usblp *usblp)
 169{
 170	struct device *dev = &usblp->intf->dev;
 171	int p;
 172
 173	dev_dbg(dev, "usblp=0x%p\n", usblp);
 174	dev_dbg(dev, "dev=0x%p\n", usblp->dev);
 175	dev_dbg(dev, "present=%d\n", usblp->present);
 176	dev_dbg(dev, "readbuf=0x%p\n", usblp->readbuf);
 177	dev_dbg(dev, "readcount=%d\n", usblp->readcount);
 178	dev_dbg(dev, "ifnum=%d\n", usblp->ifnum);
 179	for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
 180		dev_dbg(dev, "protocol[%d].alt_setting=%d\n", p,
 181			usblp->protocol[p].alt_setting);
 182		dev_dbg(dev, "protocol[%d].epwrite=%p\n", p,
 183			usblp->protocol[p].epwrite);
 184		dev_dbg(dev, "protocol[%d].epread=%p\n", p,
 185			usblp->protocol[p].epread);
 186	}
 187	dev_dbg(dev, "current_protocol=%d\n", usblp->current_protocol);
 188	dev_dbg(dev, "minor=%d\n", usblp->minor);
 189	dev_dbg(dev, "wstatus=%d\n", usblp->wstatus);
 190	dev_dbg(dev, "rstatus=%d\n", usblp->rstatus);
 191	dev_dbg(dev, "quirks=%d\n", usblp->quirks);
 192	dev_dbg(dev, "used=%d\n", usblp->used);
 193	dev_dbg(dev, "bidir=%d\n", usblp->bidir);
 194	dev_dbg(dev, "device_id_string=\"%s\"\n",
 195		usblp->device_id_string ?
 196			usblp->device_id_string + 2 :
 197			(unsigned char *)"(null)");
 198}
 199#endif
 200
 201/* Quirks: various printer quirks are handled by this table & its flags. */
 202
 203struct quirk_printer_struct {
 204	__u16 vendorId;
 205	__u16 productId;
 206	unsigned int quirks;
 207};
 208
 209#define USBLP_QUIRK_BIDIR	0x1	/* reports bidir but requires unidirectional mode (no INs/reads) */
 210#define USBLP_QUIRK_USB_INIT	0x2	/* needs vendor USB init string */
 211#define USBLP_QUIRK_BAD_CLASS	0x4	/* descriptor uses vendor-specific Class or SubClass */
 212
 213static const struct quirk_printer_struct quirk_printers[] = {
 214	{ 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
 215	{ 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
 216	{ 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
 217	{ 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
 218	{ 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
 219	{ 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
 220	{ 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
 221	{ 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
 222	{ 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
 223	{ 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
 224	{ 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
 225	{ 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
 226	{ 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
 227	{ 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <kernel@zut.de> */
 228	{ 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
 229	{ 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
 230	{ 0, 0 }
 231};
 232
 233static int usblp_wwait(struct usblp *usblp, int nonblock);
 234static int usblp_wtest(struct usblp *usblp, int nonblock);
 235static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
 236static int usblp_rtest(struct usblp *usblp, int nonblock);
 237static int usblp_submit_read(struct usblp *usblp);
 238static int usblp_select_alts(struct usblp *usblp);
 239static int usblp_set_protocol(struct usblp *usblp, int protocol);
 240static int usblp_cache_device_id_string(struct usblp *usblp);
 241
 242/* forward reference to make our lives easier */
 243static struct usb_driver usblp_driver;
 244static DEFINE_MUTEX(usblp_mutex);	/* locks the existence of usblp's */
 245
 246/*
 247 * Functions for usblp control messages.
 248 */
 249
 250static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
 251{
 252	int retval;
 253	int index = usblp->ifnum;
 254
 255	/* High byte has the interface index.
 256	   Low byte has the alternate setting.
 257	 */
 258	if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS))
 259		index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
 260
 261	retval = usb_control_msg(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
 277static int usblp_hp_channel_change_request(struct usblp *usblp, int channel, u8 *new_channel)
 278{
 279	u8 *buf;
 280	int ret;
 281
 282	buf = kzalloc(1, GFP_KERNEL);
 283	if (!buf)
 284		return -ENOMEM;
 285
 286	ret = usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST,
 287			USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE,
 288			channel, buf, 1);
 289	if (ret == 0)
 290		*new_channel = buf[0];
 291
 292	kfree(buf);
 293
 294	return ret;
 295}
 296
 297/*
 298 * See the description for usblp_select_alts() below for the usage
 299 * explanation.  Look into your /sys/kernel/debug/usb/devices and dmesg in
 300 * case of any trouble.
 301 */
 302static int proto_bias = -1;
 303
 304/*
 305 * URB callback.
 306 */
 307
 308static void usblp_bulk_read(struct urb *urb)
 309{
 310	struct usblp *usblp = urb->context;
 311	int status = urb->status;
 312	unsigned long flags;
 313
 314	if (usblp->present && usblp->used) {
 315		if (status)
 316			printk(KERN_WARNING "usblp%d: "
 317			    "nonzero read bulk status received: %d\n",
 318			    usblp->minor, status);
 319	}
 320	spin_lock_irqsave(&usblp->lock, flags);
 321	if (status < 0)
 322		usblp->rstatus = status;
 323	else
 324		usblp->rstatus = urb->actual_length;
 325	usblp->rcomplete = 1;
 326	wake_up(&usblp->rwait);
 327	spin_unlock_irqrestore(&usblp->lock, flags);
 328
 329	usb_free_urb(urb);
 330}
 331
 332static void usblp_bulk_write(struct urb *urb)
 333{
 334	struct usblp *usblp = urb->context;
 335	int status = urb->status;
 336	unsigned long flags;
 337
 338	if (usblp->present && usblp->used) {
 339		if (status)
 340			printk(KERN_WARNING "usblp%d: "
 341			    "nonzero write bulk status received: %d\n",
 342			    usblp->minor, status);
 343	}
 344	spin_lock_irqsave(&usblp->lock, flags);
 345	if (status < 0)
 346		usblp->wstatus = status;
 347	else
 348		usblp->wstatus = urb->actual_length;
 349	usblp->no_paper = 0;
 350	usblp->wcomplete = 1;
 351	wake_up(&usblp->wwait);
 352	spin_unlock_irqrestore(&usblp->lock, flags);
 353
 354	usb_free_urb(urb);
 355}
 356
 357/*
 358 * Get and print printer errors.
 359 */
 360
 361static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
 362
 363static int usblp_check_status(struct usblp *usblp, int err)
 364{
 365	unsigned char status, newerr = 0;
 366	int error;
 367
 368	mutex_lock(&usblp->mut);
 369	if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
 370		mutex_unlock(&usblp->mut);
 371		printk_ratelimited(KERN_ERR
 372				"usblp%d: error %d reading printer status\n",
 373				usblp->minor, error);
 374		return 0;
 375	}
 376	status = *usblp->statusbuf;
 377	mutex_unlock(&usblp->mut);
 378
 379	if (~status & LP_PERRORP)
 380		newerr = 3;
 381	if (status & LP_POUTPA)
 382		newerr = 1;
 383	if (~status & LP_PSELECD)
 384		newerr = 2;
 385
 386	if (newerr != err) {
 387		printk(KERN_INFO "usblp%d: %s\n",
 388		   usblp->minor, usblp_messages[newerr]);
 389	}
 390
 391	return newerr;
 392}
 393
 394static int handle_bidir(struct usblp *usblp)
 395{
 396	if (usblp->bidir && usblp->used) {
 397		if (usblp_submit_read(usblp) < 0)
 398			return -EIO;
 399	}
 400	return 0;
 401}
 402
 403/*
 404 * File op functions.
 405 */
 406
 407static int usblp_open(struct inode *inode, struct file *file)
 408{
 409	int minor = iminor(inode);
 410	struct usblp *usblp;
 411	struct usb_interface *intf;
 412	int retval;
 413
 414	if (minor < 0)
 415		return -ENODEV;
 416
 417	mutex_lock(&usblp_mutex);
 418
 419	retval = -ENODEV;
 420	intf = usb_find_interface(&usblp_driver, minor);
 421	if (!intf)
 422		goto out;
 423	usblp = usb_get_intfdata(intf);
 424	if (!usblp || !usblp->dev || !usblp->present)
 425		goto out;
 426
 427	retval = -EBUSY;
 428	if (usblp->used)
 429		goto out;
 430
 431	/*
 432	 * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
 433	 *  - We do not want persistent state which close(2) does not clear
 434	 *  - It is not used anyway, according to CUPS people
 435	 */
 436
 437	retval = usb_autopm_get_interface(intf);
 438	if (retval < 0)
 439		goto out;
 440	usblp->used = 1;
 441	file->private_data = usblp;
 442
 443	usblp->wcomplete = 1; /* we begin writeable */
 444	usblp->wstatus = 0;
 445	usblp->rcomplete = 0;
 446
 447	if (handle_bidir(usblp) < 0) {
 448		usb_autopm_put_interface(intf);
 449		usblp->used = 0;
 450		file->private_data = NULL;
 451		retval = -EIO;
 452	}
 453out:
 454	mutex_unlock(&usblp_mutex);
 455	return retval;
 456}
 457
 458static void usblp_cleanup(struct usblp *usblp)
 459{
 460	printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
 461
 462	kfree(usblp->readbuf);
 463	kfree(usblp->device_id_string);
 464	kfree(usblp->statusbuf);
 465	usb_put_intf(usblp->intf);
 466	kfree(usblp);
 467}
 468
 469static void usblp_unlink_urbs(struct usblp *usblp)
 470{
 471	usb_kill_anchored_urbs(&usblp->urbs);
 472}
 473
 474static int usblp_release(struct inode *inode, struct file *file)
 475{
 476	struct usblp *usblp = file->private_data;
 477
 478	usblp->flags &= ~LP_ABORT;
 479
 480	mutex_lock(&usblp_mutex);
 481	usblp->used = 0;
 482	if (usblp->present)
 483		usblp_unlink_urbs(usblp);
 484
 485	usb_autopm_put_interface(usblp->intf);
 486
 487	if (!usblp->present)		/* finish cleanup from disconnect */
 488		usblp_cleanup(usblp);	/* any URBs must be dead */
 489
 490	mutex_unlock(&usblp_mutex);
 491	return 0;
 492}
 493
 494/* No kernel lock - fine */
 495static __poll_t usblp_poll(struct file *file, struct poll_table_struct *wait)
 496{
 497	struct usblp *usblp = file->private_data;
 498	__poll_t ret = 0;
 499	unsigned long flags;
 500
 
 501	/* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
 502	poll_wait(file, &usblp->rwait, wait);
 503	poll_wait(file, &usblp->wwait, wait);
 504
 505	mutex_lock(&usblp->mut);
 506	if (!usblp->present)
 507		ret |= EPOLLHUP;
 508	mutex_unlock(&usblp->mut);
 509
 510	spin_lock_irqsave(&usblp->lock, flags);
 511	if (usblp->bidir && usblp->rcomplete)
 512		ret |= EPOLLIN  | EPOLLRDNORM;
 513	if (usblp->no_paper || usblp->wcomplete)
 514		ret |= EPOLLOUT | EPOLLWRNORM;
 515	spin_unlock_irqrestore(&usblp->lock, flags);
 516	return ret;
 517}
 518
 519static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 520{
 521	struct usblp *usblp = file->private_data;
 522	int length, err, i;
 523	unsigned char newChannel;
 524	int status;
 525	int twoints[2];
 526	int retval = 0;
 527
 528	mutex_lock(&usblp->mut);
 529	if (!usblp->present) {
 530		retval = -ENODEV;
 531		goto done;
 532	}
 533
 534	dev_dbg(&usblp->intf->dev,
 535		"usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)\n", cmd,
 536		_IOC_TYPE(cmd), _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
 537
 538	if (_IOC_TYPE(cmd) == 'P')	/* new-style ioctl number */
 539
 540		switch (_IOC_NR(cmd)) {
 541
 542		case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
 543			if (_IOC_DIR(cmd) != _IOC_READ) {
 544				retval = -EINVAL;
 545				goto done;
 546			}
 547
 548			length = usblp_cache_device_id_string(usblp);
 549			if (length < 0) {
 550				retval = length;
 551				goto done;
 552			}
 553			if (length > _IOC_SIZE(cmd))
 554				length = _IOC_SIZE(cmd); /* truncate */
 555
 556			if (copy_to_user((void __user *) arg,
 557					usblp->device_id_string,
 558					(unsigned long) length)) {
 559				retval = -EFAULT;
 560				goto done;
 561			}
 562
 563			break;
 564
 565		case IOCNR_GET_PROTOCOLS:
 566			if (_IOC_DIR(cmd) != _IOC_READ ||
 567			    _IOC_SIZE(cmd) < sizeof(twoints)) {
 568				retval = -EINVAL;
 569				goto done;
 570			}
 571
 572			twoints[0] = usblp->current_protocol;
 573			twoints[1] = 0;
 574			for (i = USBLP_FIRST_PROTOCOL;
 575			     i <= USBLP_LAST_PROTOCOL; i++) {
 576				if (usblp->protocol[i].alt_setting >= 0)
 577					twoints[1] |= (1<<i);
 578			}
 579
 580			if (copy_to_user((void __user *)arg,
 581					(unsigned char *)twoints,
 582					sizeof(twoints))) {
 583				retval = -EFAULT;
 584				goto done;
 585			}
 586
 587			break;
 588
 589		case IOCNR_SET_PROTOCOL:
 590			if (_IOC_DIR(cmd) != _IOC_WRITE) {
 591				retval = -EINVAL;
 592				goto done;
 593			}
 594
 595#ifdef DEBUG
 596			if (arg == -10) {
 597				usblp_dump(usblp);
 598				break;
 599			}
 600#endif
 601
 602			usblp_unlink_urbs(usblp);
 603			retval = usblp_set_protocol(usblp, arg);
 604			if (retval < 0) {
 605				usblp_set_protocol(usblp,
 606					usblp->current_protocol);
 607			}
 608			break;
 609
 610		case IOCNR_HP_SET_CHANNEL:
 611			if (_IOC_DIR(cmd) != _IOC_WRITE ||
 612			    le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
 613			    usblp->quirks & USBLP_QUIRK_BIDIR) {
 614				retval = -EINVAL;
 615				goto done;
 616			}
 617
 618			err = usblp_hp_channel_change_request(usblp,
 619				arg, &newChannel);
 620			if (err < 0) {
 621				dev_err(&usblp->dev->dev,
 622					"usblp%d: error = %d setting "
 623					"HP channel\n",
 624					usblp->minor, err);
 625				retval = -EIO;
 626				goto done;
 627			}
 628
 629			dev_dbg(&usblp->intf->dev,
 630				"usblp%d requested/got HP channel %ld/%d\n",
 631				usblp->minor, arg, newChannel);
 632			break;
 633
 634		case IOCNR_GET_BUS_ADDRESS:
 635			if (_IOC_DIR(cmd) != _IOC_READ ||
 636			    _IOC_SIZE(cmd) < sizeof(twoints)) {
 637				retval = -EINVAL;
 638				goto done;
 639			}
 640
 641			twoints[0] = usblp->dev->bus->busnum;
 642			twoints[1] = usblp->dev->devnum;
 643			if (copy_to_user((void __user *)arg,
 644					(unsigned char *)twoints,
 645					sizeof(twoints))) {
 646				retval = -EFAULT;
 647				goto done;
 648			}
 649
 650			dev_dbg(&usblp->intf->dev,
 651				"usblp%d is bus=%d, device=%d\n",
 652				usblp->minor, twoints[0], twoints[1]);
 653			break;
 654
 655		case IOCNR_GET_VID_PID:
 656			if (_IOC_DIR(cmd) != _IOC_READ ||
 657			    _IOC_SIZE(cmd) < sizeof(twoints)) {
 658				retval = -EINVAL;
 659				goto done;
 660			}
 661
 662			twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
 663			twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
 664			if (copy_to_user((void __user *)arg,
 665					(unsigned char *)twoints,
 666					sizeof(twoints))) {
 667				retval = -EFAULT;
 668				goto done;
 669			}
 670
 671			dev_dbg(&usblp->intf->dev,
 672				"usblp%d is VID=0x%4.4X, PID=0x%4.4X\n",
 673				usblp->minor, twoints[0], twoints[1]);
 674			break;
 675
 676		case IOCNR_SOFT_RESET:
 677			if (_IOC_DIR(cmd) != _IOC_NONE) {
 678				retval = -EINVAL;
 679				goto done;
 680			}
 681			retval = usblp_reset(usblp);
 682			break;
 683		default:
 684			retval = -ENOTTY;
 685		}
 686	else	/* old-style ioctl value */
 687		switch (cmd) {
 688
 689		case LPGETSTATUS:
 690			retval = usblp_read_status(usblp, usblp->statusbuf);
 691			if (retval) {
 692				printk_ratelimited(KERN_ERR "usblp%d:"
 693					    "failed reading printer status (%d)\n",
 694					    usblp->minor, retval);
 695				retval = -EIO;
 696				goto done;
 697			}
 698			status = *usblp->statusbuf;
 699			if (copy_to_user((void __user *)arg, &status, sizeof(int)))
 700				retval = -EFAULT;
 701			break;
 702
 703		case LPABORT:
 704			if (arg)
 705				usblp->flags |= LP_ABORT;
 706			else
 707				usblp->flags &= ~LP_ABORT;
 708			break;
 709
 710		default:
 711			retval = -ENOTTY;
 712		}
 713
 714done:
 715	mutex_unlock(&usblp->mut);
 716	return retval;
 717}
 718
 719static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
 720{
 721	struct urb *urb;
 722	char *writebuf;
 723
 724	writebuf = kmalloc(transfer_length, GFP_KERNEL);
 725	if (writebuf == NULL)
 726		return NULL;
 727	urb = usb_alloc_urb(0, GFP_KERNEL);
 728	if (urb == NULL) {
 729		kfree(writebuf);
 730		return NULL;
 731	}
 732
 733	usb_fill_bulk_urb(urb, usblp->dev,
 734		usb_sndbulkpipe(usblp->dev,
 735		 usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
 736		writebuf, transfer_length, usblp_bulk_write, usblp);
 737	urb->transfer_flags |= URB_FREE_BUFFER;
 738
 739	return urb;
 740}
 741
 742static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 743{
 744	struct usblp *usblp = file->private_data;
 745	struct urb *writeurb;
 746	int rv;
 747	int transfer_length;
 748	ssize_t writecount = 0;
 749
 750	if (mutex_lock_interruptible(&usblp->wmut)) {
 751		rv = -EINTR;
 752		goto raise_biglock;
 753	}
 754	if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
 755		goto raise_wait;
 756
 757	while (writecount < count) {
 758		/*
 759		 * Step 1: Submit next block.
 760		 */
 761		if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
 762			transfer_length = USBLP_BUF_SIZE;
 763
 764		rv = -ENOMEM;
 765		writeurb = usblp_new_writeurb(usblp, transfer_length);
 766		if (writeurb == NULL)
 767			goto raise_urb;
 768		usb_anchor_urb(writeurb, &usblp->urbs);
 769
 770		if (copy_from_user(writeurb->transfer_buffer,
 771				   buffer + writecount, transfer_length)) {
 772			rv = -EFAULT;
 773			goto raise_badaddr;
 774		}
 775
 776		spin_lock_irq(&usblp->lock);
 777		usblp->wcomplete = 0;
 778		spin_unlock_irq(&usblp->lock);
 779		if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
 780			usblp->wstatus = 0;
 781			spin_lock_irq(&usblp->lock);
 782			usblp->no_paper = 0;
 783			usblp->wcomplete = 1;
 784			wake_up(&usblp->wwait);
 785			spin_unlock_irq(&usblp->lock);
 786			if (rv != -ENOMEM)
 787				rv = -EIO;
 788			goto raise_submit;
 789		}
 790
 791		/*
 792		 * Step 2: Wait for transfer to end, collect results.
 793		 */
 794		rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
 795		if (rv < 0) {
 796			if (rv == -EAGAIN) {
 797				/* Presume that it's going to complete well. */
 798				writecount += transfer_length;
 799			}
 800			if (rv == -ENOSPC) {
 801				spin_lock_irq(&usblp->lock);
 802				usblp->no_paper = 1;	/* Mark for poll(2) */
 803				spin_unlock_irq(&usblp->lock);
 804				writecount += transfer_length;
 805			}
 806			/* Leave URB dangling, to be cleaned on close. */
 807			goto collect_error;
 808		}
 809
 810		if (usblp->wstatus < 0) {
 811			rv = -EIO;
 812			goto collect_error;
 813		}
 814		/*
 815		 * This is critical: it must be our URB, not other writer's.
 816		 * The wmut exists mainly to cover us here.
 817		 */
 818		writecount += usblp->wstatus;
 819	}
 820
 821	mutex_unlock(&usblp->wmut);
 822	return writecount;
 823
 824raise_submit:
 825raise_badaddr:
 826	usb_unanchor_urb(writeurb);
 827	usb_free_urb(writeurb);
 828raise_urb:
 829raise_wait:
 830collect_error:		/* Out of raise sequence */
 831	mutex_unlock(&usblp->wmut);
 832raise_biglock:
 833	return writecount ? writecount : rv;
 834}
 835
 836/*
 837 * Notice that we fail to restart in a few cases: on EFAULT, on restart
 838 * error, etc. This is the historical behaviour. In all such cases we return
 839 * EIO, and applications loop in order to get the new read going.
 840 */
 841static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
 842{
 843	struct usblp *usblp = file->private_data;
 844	ssize_t count;
 845	ssize_t avail;
 846	int rv;
 847
 848	if (!usblp->bidir)
 849		return -EINVAL;
 850
 851	rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
 852	if (rv < 0)
 853		return rv;
 854
 855	if (!usblp->present) {
 856		count = -ENODEV;
 857		goto done;
 858	}
 859
 860	if ((avail = usblp->rstatus) < 0) {
 861		printk(KERN_ERR "usblp%d: error %d reading from printer\n",
 862		    usblp->minor, (int)avail);
 863		usblp_submit_read(usblp);
 864		count = -EIO;
 865		goto done;
 866	}
 867
 868	count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
 869	if (count != 0 &&
 870	    copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
 871		count = -EFAULT;
 872		goto done;
 873	}
 874
 875	if ((usblp->readcount += count) == avail) {
 876		if (usblp_submit_read(usblp) < 0) {
 877			/* We don't want to leak USB return codes into errno. */
 878			if (count == 0)
 879				count = -EIO;
 880			goto done;
 881		}
 882	}
 883
 884done:
 885	mutex_unlock(&usblp->mut);
 886	return count;
 887}
 888
 889/*
 890 * Wait for the write path to come idle.
 891 * This is called under the ->wmut, so the idle path stays idle.
 892 *
 893 * Our write path has a peculiar property: it does not buffer like a tty,
 894 * but waits for the write to succeed. This allows our ->release to bug out
 895 * without waiting for writes to drain. But it obviously does not work
 896 * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
 897 * select(2) or poll(2) to wait for the buffer to drain before closing.
 898 * Alternatively, set blocking mode with fcntl and issue a zero-size write.
 899 */
 900static int usblp_wwait(struct usblp *usblp, int nonblock)
 901{
 902	DECLARE_WAITQUEUE(waita, current);
 903	int rc;
 904	int err = 0;
 905
 906	add_wait_queue(&usblp->wwait, &waita);
 907	for (;;) {
 908		if (mutex_lock_interruptible(&usblp->mut)) {
 909			rc = -EINTR;
 910			break;
 911		}
 912		set_current_state(TASK_INTERRUPTIBLE);
 913		rc = usblp_wtest(usblp, nonblock);
 914		mutex_unlock(&usblp->mut);
 915		if (rc <= 0)
 916			break;
 917
 918		if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
 919			if (usblp->flags & LP_ABORT) {
 920				err = usblp_check_status(usblp, err);
 921				if (err == 1) {	/* Paper out */
 922					rc = -ENOSPC;
 923					break;
 924				}
 925			} else {
 926				/* Prod the printer, Gentoo#251237. */
 927				mutex_lock(&usblp->mut);
 928				usblp_read_status(usblp, usblp->statusbuf);
 929				mutex_unlock(&usblp->mut);
 930			}
 931		}
 932	}
 933	set_current_state(TASK_RUNNING);
 934	remove_wait_queue(&usblp->wwait, &waita);
 935	return rc;
 936}
 937
 938static int usblp_wtest(struct usblp *usblp, int nonblock)
 939{
 940	unsigned long flags;
 941
 942	if (!usblp->present)
 943		return -ENODEV;
 944	if (signal_pending(current))
 945		return -EINTR;
 946	spin_lock_irqsave(&usblp->lock, flags);
 947	if (usblp->wcomplete) {
 948		spin_unlock_irqrestore(&usblp->lock, flags);
 949		return 0;
 950	}
 951	spin_unlock_irqrestore(&usblp->lock, flags);
 952	if (nonblock)
 953		return -EAGAIN;
 954	return 1;
 955}
 956
 957/*
 958 * Wait for read bytes to become available. This probably should have been
 959 * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
 960 * name for functions which lock and return.
 961 *
 962 * We do not use wait_event_interruptible because it makes locking iffy.
 963 */
 964static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
 965{
 966	DECLARE_WAITQUEUE(waita, current);
 967	int rc;
 968
 969	add_wait_queue(&usblp->rwait, &waita);
 970	for (;;) {
 971		if (mutex_lock_interruptible(&usblp->mut)) {
 972			rc = -EINTR;
 973			break;
 974		}
 975		set_current_state(TASK_INTERRUPTIBLE);
 976		if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
 977			mutex_unlock(&usblp->mut);
 978			break;
 979		}
 980		if (rc == 0)	/* Keep it locked */
 981			break;
 982		mutex_unlock(&usblp->mut);
 983		schedule();
 984	}
 985	set_current_state(TASK_RUNNING);
 986	remove_wait_queue(&usblp->rwait, &waita);
 987	return rc;
 988}
 989
 990static int usblp_rtest(struct usblp *usblp, int nonblock)
 991{
 992	unsigned long flags;
 993
 994	if (!usblp->present)
 995		return -ENODEV;
 996	if (signal_pending(current))
 997		return -EINTR;
 998	spin_lock_irqsave(&usblp->lock, flags);
 999	if (usblp->rcomplete) {
1000		spin_unlock_irqrestore(&usblp->lock, flags);
1001		return 0;
1002	}
1003	spin_unlock_irqrestore(&usblp->lock, flags);
1004	if (nonblock)
1005		return -EAGAIN;
1006	return 1;
1007}
1008
1009/*
1010 * Please check ->bidir and other such things outside for now.
1011 */
1012static int usblp_submit_read(struct usblp *usblp)
1013{
1014	struct urb *urb;
1015	unsigned long flags;
1016	int rc;
1017
1018	rc = -ENOMEM;
1019	urb = usb_alloc_urb(0, GFP_KERNEL);
1020	if (urb == NULL)
1021		goto raise_urb;
1022
1023	usb_fill_bulk_urb(urb, usblp->dev,
1024		usb_rcvbulkpipe(usblp->dev,
1025		  usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
1026		usblp->readbuf, USBLP_BUF_SIZE_IN,
1027		usblp_bulk_read, usblp);
1028	usb_anchor_urb(urb, &usblp->urbs);
1029
1030	spin_lock_irqsave(&usblp->lock, flags);
1031	usblp->readcount = 0; /* XXX Why here? */
1032	usblp->rcomplete = 0;
1033	spin_unlock_irqrestore(&usblp->lock, flags);
1034	if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
1035		dev_dbg(&usblp->intf->dev, "error submitting urb (%d)\n", rc);
1036		spin_lock_irqsave(&usblp->lock, flags);
1037		usblp->rstatus = rc;
1038		usblp->rcomplete = 1;
1039		spin_unlock_irqrestore(&usblp->lock, flags);
1040		goto raise_submit;
1041	}
1042
1043	return 0;
1044
1045raise_submit:
1046	usb_unanchor_urb(urb);
1047	usb_free_urb(urb);
1048raise_urb:
1049	return rc;
1050}
1051
1052/*
1053 * Checks for printers that have quirks, such as requiring unidirectional
1054 * communication but reporting bidirectional; currently some HP printers
1055 * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1056 * sent at each open (like some Epsons).
1057 * Returns 1 if found, 0 if not found.
1058 *
1059 * HP recommended that we use the bidirectional interface but
1060 * don't attempt any bulk IN transfers from the IN endpoint.
1061 * Here's some more detail on the problem:
1062 * The problem is not that it isn't bidirectional though. The problem
1063 * is that if you request a device ID, or status information, while
1064 * the buffers are full, the return data will end up in the print data
1065 * buffer. For example if you make sure you never request the device ID
1066 * while you are sending print data, and you don't try to query the
1067 * printer status every couple of milliseconds, you will probably be OK.
1068 */
1069static unsigned int usblp_quirks(__u16 vendor, __u16 product)
1070{
1071	int i;
1072
1073	for (i = 0; quirk_printers[i].vendorId; i++) {
1074		if (vendor == quirk_printers[i].vendorId &&
1075		    product == quirk_printers[i].productId)
1076			return quirk_printers[i].quirks;
1077	}
1078	return 0;
1079}
1080
1081static const struct file_operations usblp_fops = {
1082	.owner =	THIS_MODULE,
1083	.read =		usblp_read,
1084	.write =	usblp_write,
1085	.poll =		usblp_poll,
1086	.unlocked_ioctl =	usblp_ioctl,
1087	.compat_ioctl =		usblp_ioctl,
1088	.open =		usblp_open,
1089	.release =	usblp_release,
1090	.llseek =	noop_llseek,
1091};
1092
1093static char *usblp_devnode(const struct device *dev, umode_t *mode)
1094{
1095	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1096}
1097
1098static struct usb_class_driver usblp_class = {
1099	.name =		"lp%d",
1100	.devnode =	usblp_devnode,
1101	.fops =		&usblp_fops,
1102	.minor_base =	USBLP_MINOR_BASE,
1103};
1104
1105static ssize_t ieee1284_id_show(struct device *dev, struct device_attribute *attr, char *buf)
1106{
1107	struct usb_interface *intf = to_usb_interface(dev);
1108	struct usblp *usblp = usb_get_intfdata(intf);
1109
1110	if (usblp->device_id_string[0] == 0 &&
1111	    usblp->device_id_string[1] == 0)
1112		return 0;
1113
1114	return sprintf(buf, "%s", usblp->device_id_string+2);
1115}
1116
1117static DEVICE_ATTR_RO(ieee1284_id);
1118
1119static struct attribute *usblp_attrs[] = {
1120	&dev_attr_ieee1284_id.attr,
1121	NULL,
1122};
1123ATTRIBUTE_GROUPS(usblp);
1124
1125static int usblp_probe(struct usb_interface *intf,
1126		       const struct usb_device_id *id)
1127{
1128	struct usb_device *dev = interface_to_usbdev(intf);
1129	struct usblp *usblp;
1130	int protocol;
1131	int retval;
1132
1133	/* Malloc and start initializing usblp structure so we can use it
1134	 * directly. */
1135	usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1136	if (!usblp) {
1137		retval = -ENOMEM;
1138		goto abort_ret;
1139	}
1140	usblp->dev = dev;
1141	mutex_init(&usblp->wmut);
1142	mutex_init(&usblp->mut);
1143	spin_lock_init(&usblp->lock);
1144	init_waitqueue_head(&usblp->rwait);
1145	init_waitqueue_head(&usblp->wwait);
1146	init_usb_anchor(&usblp->urbs);
1147	usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1148	usblp->intf = usb_get_intf(intf);
1149
1150	/* Malloc device ID string buffer to the largest expected length,
1151	 * since we can re-query it on an ioctl and a dynamic string
1152	 * could change in length. */
1153	if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1154		retval = -ENOMEM;
1155		goto abort;
1156	}
1157
1158	/*
1159	 * Allocate read buffer. We somewhat wastefully
1160	 * malloc both regardless of bidirectionality, because the
1161	 * alternate setting can be changed later via an ioctl.
1162	 */
1163	if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1164		retval = -ENOMEM;
1165		goto abort;
1166	}
1167
1168	/* Allocate buffer for printer status */
1169	usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1170	if (!usblp->statusbuf) {
1171		retval = -ENOMEM;
1172		goto abort;
1173	}
1174
1175	/* Lookup quirks for this printer. */
1176	usblp->quirks = usblp_quirks(
1177		le16_to_cpu(dev->descriptor.idVendor),
1178		le16_to_cpu(dev->descriptor.idProduct));
1179
1180	/* Analyze and pick initial alternate settings and endpoints. */
1181	protocol = usblp_select_alts(usblp);
1182	if (protocol < 0) {
1183		dev_dbg(&intf->dev,
1184			"incompatible printer-class device 0x%4.4X/0x%4.4X\n",
1185			le16_to_cpu(dev->descriptor.idVendor),
1186			le16_to_cpu(dev->descriptor.idProduct));
1187		retval = -ENODEV;
1188		goto abort;
1189	}
1190
1191	/* Setup the selected alternate setting and endpoints. */
1192	if (usblp_set_protocol(usblp, protocol) < 0) {
1193		retval = -ENODEV;	/* ->probe isn't ->ioctl */
1194		goto abort;
1195	}
1196
1197	/* Retrieve and store the device ID string. */
1198	usblp_cache_device_id_string(usblp);
1199
1200#ifdef DEBUG
1201	usblp_check_status(usblp, 0);
1202#endif
1203
1204	usb_set_intfdata(intf, usblp);
1205
1206	usblp->present = 1;
1207
1208	retval = usb_register_dev(intf, &usblp_class);
1209	if (retval) {
1210		dev_err(&intf->dev,
1211			"usblp: Not able to get a minor (base %u, slice default): %d\n",
1212			USBLP_MINOR_BASE, retval);
1213		goto abort_intfdata;
1214	}
1215	usblp->minor = intf->minor;
1216	dev_info(&intf->dev,
1217		"usblp%d: USB %sdirectional printer dev %d if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1218		usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1219		usblp->ifnum,
1220		usblp->protocol[usblp->current_protocol].alt_setting,
1221		usblp->current_protocol,
1222		le16_to_cpu(usblp->dev->descriptor.idVendor),
1223		le16_to_cpu(usblp->dev->descriptor.idProduct));
1224
1225	return 0;
1226
1227abort_intfdata:
1228	usb_set_intfdata(intf, NULL);
1229abort:
1230	kfree(usblp->readbuf);
1231	kfree(usblp->statusbuf);
1232	kfree(usblp->device_id_string);
1233	usb_put_intf(usblp->intf);
1234	kfree(usblp);
1235abort_ret:
1236	return retval;
1237}
1238
1239/*
1240 * We are a "new" style driver with usb_device_id table,
1241 * but our requirements are too intricate for simple match to handle.
1242 *
1243 * The "proto_bias" option may be used to specify the preferred protocol
1244 * for all USB printers (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
1245 * 3=USB_CLASS_PRINTER/1/3).  If the device supports the preferred protocol,
1246 * then we bind to it.
1247 *
1248 * The best interface for us is USB_CLASS_PRINTER/1/2, because it
1249 * is compatible with a stream of characters. If we find it, we bind to it.
1250 *
1251 * Note that the people from hpoj.sourceforge.net need to be able to
1252 * bind to USB_CLASS_PRINTER/1/3 (MLC/1284.4), so we provide them ioctls
1253 * for this purpose.
1254 *
1255 * Failing USB_CLASS_PRINTER/1/2, we look for USB_CLASS_PRINTER/1/3,
1256 * even though it's probably not stream-compatible, because this matches
1257 * the behaviour of the old code.
1258 *
1259 * If nothing else, we bind to USB_CLASS_PRINTER/1/1
1260 * - the unidirectional interface.
1261 */
1262static int usblp_select_alts(struct usblp *usblp)
1263{
1264	struct usb_interface *if_alt;
1265	struct usb_host_interface *ifd;
1266	struct usb_endpoint_descriptor *epwrite, *epread;
1267	int p, i;
1268	int res;
1269
1270	if_alt = usblp->intf;
1271
1272	for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1273		usblp->protocol[p].alt_setting = -1;
1274
1275	/* Find out what we have. */
1276	for (i = 0; i < if_alt->num_altsetting; i++) {
1277		ifd = &if_alt->altsetting[i];
1278
1279		if (ifd->desc.bInterfaceClass != USB_CLASS_PRINTER ||
1280		    ifd->desc.bInterfaceSubClass != 1)
1281			if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1282				continue;
1283
1284		if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1285		    ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1286			continue;
1287
1288		/* Look for the expected bulk endpoints. */
1289		if (ifd->desc.bInterfaceProtocol > 1) {
1290			res = usb_find_common_endpoints(ifd,
1291					&epread, &epwrite, NULL, NULL);
1292		} else {
1293			epread = NULL;
1294			res = usb_find_bulk_out_endpoint(ifd, &epwrite);
1295		}
1296
1297		/* Ignore buggy hardware without the right endpoints. */
1298		if (res)
1299			continue;
1300
1301		/* Turn off reads for buggy bidirectional printers. */
1302		if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1303			printk(KERN_INFO "usblp%d: Disabling reads from "
1304			    "problematic bidirectional printer\n",
1305			    usblp->minor);
1306			epread = NULL;
1307		}
1308
1309		usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1310				ifd->desc.bAlternateSetting;
1311		usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1312		usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1313	}
1314
1315	/* If our requested protocol is supported, then use it. */
1316	if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1317	    proto_bias <= USBLP_LAST_PROTOCOL &&
1318	    usblp->protocol[proto_bias].alt_setting != -1)
1319		return proto_bias;
1320
1321	/* Ordering is important here. */
1322	if (usblp->protocol[2].alt_setting != -1)
1323		return 2;
1324	if (usblp->protocol[1].alt_setting != -1)
1325		return 1;
1326	if (usblp->protocol[3].alt_setting != -1)
1327		return 3;
1328
1329	/* If nothing is available, then don't bind to this device. */
1330	return -1;
1331}
1332
1333static int usblp_set_protocol(struct usblp *usblp, int protocol)
1334{
1335	int r, alts;
1336
1337	if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1338		return -EINVAL;
1339
1340	/* Don't unnecessarily set the interface if there's a single alt. */
1341	if (usblp->intf->num_altsetting > 1) {
1342		alts = usblp->protocol[protocol].alt_setting;
1343		if (alts < 0)
1344			return -EINVAL;
1345		r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1346		if (r < 0) {
1347			printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1348				alts, usblp->ifnum);
1349			return r;
1350		}
1351	}
1352
1353	usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1354	usblp->current_protocol = protocol;
1355	dev_dbg(&usblp->intf->dev, "usblp%d set protocol %d\n",
1356		usblp->minor, protocol);
1357	return 0;
1358}
1359
1360/* Retrieves and caches device ID string.
1361 * Returns length, including length bytes but not null terminator.
1362 * On error, returns a negative errno value. */
1363static int usblp_cache_device_id_string(struct usblp *usblp)
1364{
1365	int err, length;
1366
1367	err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1368	if (err < 0) {
1369		dev_dbg(&usblp->intf->dev,
1370			"usblp%d: error = %d reading IEEE-1284 Device ID string\n",
1371			usblp->minor, err);
1372		usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1373		return -EIO;
1374	}
1375
1376	/* First two bytes are length in big-endian.
1377	 * They count themselves, and we copy them into
1378	 * the user's buffer. */
1379	length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1380	if (length < 2)
1381		length = 2;
1382	else if (length >= USBLP_DEVICE_ID_SIZE)
1383		length = USBLP_DEVICE_ID_SIZE - 1;
1384	usblp->device_id_string[length] = '\0';
1385
1386	dev_dbg(&usblp->intf->dev, "usblp%d Device ID string [len=%d]=\"%s\"\n",
1387		usblp->minor, length, &usblp->device_id_string[2]);
1388
1389	return length;
1390}
1391
1392static void usblp_disconnect(struct usb_interface *intf)
1393{
1394	struct usblp *usblp = usb_get_intfdata(intf);
1395
1396	usb_deregister_dev(intf, &usblp_class);
1397
1398	if (!usblp || !usblp->dev) {
1399		dev_err(&intf->dev, "bogus disconnect\n");
1400		BUG();
1401	}
1402
1403	mutex_lock(&usblp_mutex);
1404	mutex_lock(&usblp->mut);
1405	usblp->present = 0;
1406	wake_up(&usblp->wwait);
1407	wake_up(&usblp->rwait);
1408	usb_set_intfdata(intf, NULL);
1409
1410	usblp_unlink_urbs(usblp);
1411	mutex_unlock(&usblp->mut);
1412	usb_poison_anchored_urbs(&usblp->urbs);
1413
1414	if (!usblp->used)
1415		usblp_cleanup(usblp);
1416
1417	mutex_unlock(&usblp_mutex);
1418}
1419
1420static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1421{
1422	struct usblp *usblp = usb_get_intfdata(intf);
1423
1424	usblp_unlink_urbs(usblp);
1425#if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1426	/* not strictly necessary, but just in case */
1427	wake_up(&usblp->wwait);
1428	wake_up(&usblp->rwait);
1429#endif
1430
1431	return 0;
1432}
1433
1434static int usblp_resume(struct usb_interface *intf)
1435{
1436	struct usblp *usblp = usb_get_intfdata(intf);
1437	int r;
1438
1439	r = handle_bidir(usblp);
1440
1441	return r;
1442}
1443
1444static const struct usb_device_id usblp_ids[] = {
1445	{ USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 1) },
1446	{ USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 2) },
1447	{ USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 3) },
1448	{ USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 1) },
1449	{ USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 2) },
1450	{ USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 3) },
1451	{ USB_DEVICE(0x04b8, 0x0202) },	/* Seiko Epson Receipt Printer M129C */
1452	{ }						/* Terminating entry */
1453};
1454
1455MODULE_DEVICE_TABLE(usb, usblp_ids);
1456
1457static struct usb_driver usblp_driver = {
1458	.name =		"usblp",
1459	.probe =	usblp_probe,
1460	.disconnect =	usblp_disconnect,
1461	.suspend =	usblp_suspend,
1462	.resume =	usblp_resume,
1463	.id_table =	usblp_ids,
1464	.dev_groups =	usblp_groups,
1465	.supports_autosuspend =	1,
1466};
1467
1468module_usb_driver(usblp_driver);
1469
1470MODULE_AUTHOR(DRIVER_AUTHOR);
1471MODULE_DESCRIPTION(DRIVER_DESC);
1472module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1473MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1474MODULE_LICENSE("GPL");