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android-kvm / linux / 49201b90af818654c5506a0decc18e111eadcb66 / . / drivers / usb / class / usblp.c
blob: f27b4aecff3d497f0122de042a8b5d06881565be [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* usblp.c
*
* Copyright (c) 1999 Michael Gee <michael@linuxspecific.com>
* Copyright (c) 1999 Pavel Machek <pavel@ucw.cz>
* Copyright (c) 2000 Randy Dunlap <rdunlap@xenotime.net>
* Copyright (c) 2000 Vojtech Pavlik <vojtech@suse.cz>
# Copyright (c) 2001 Pete Zaitcev <zaitcev@redhat.com>
# Copyright (c) 2001 David Paschal <paschal@rcsis.com>
* Copyright (c) 2006 Oliver Neukum <oliver@neukum.name>
*
* USB Printer Device Class driver for USB printers and printer cables
*
* Sponsored by SuSE
*
* ChangeLog:
* v0.1 - thorough cleaning, URBification, almost a rewrite
* v0.2 - some more cleanups
* v0.3 - cleaner again, waitqueue fixes
* v0.4 - fixes in unidirectional mode
* v0.5 - add DEVICE_ID string support
* v0.6 - never time out
* v0.7 - fixed bulk-IN read and poll (David Paschal)
* v0.8 - add devfs support
* v0.9 - fix unplug-while-open paths
* v0.10- remove sleep_on, fix error on oom (oliver@neukum.org)
* v0.11 - add proto_bias option (Pete Zaitcev)
* v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
* v0.13 - alloc space for statusbuf (<status> not on stack);
* use usb_alloc_coherent() for read buf & write buf;
* none - Maintained in Linux kernel after v0.13
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched/signal.h>
#include <linux/signal.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/lp.h>
#include <linux/mutex.h>
#undef DEBUG
#include <linux/usb.h>
#include <linux/usb/ch9.h>
#include <linux/ratelimit.h>
/*
* Version Information
*/
#define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
#define DRIVER_DESC "USB Printer Device Class driver"
#define USBLP_BUF_SIZE 8192
#define USBLP_BUF_SIZE_IN 1024
#define USBLP_DEVICE_ID_SIZE 1024
/* ioctls: */
#define IOCNR_GET_DEVICE_ID 1
#define IOCNR_GET_PROTOCOLS 2
#define IOCNR_SET_PROTOCOL 3
#define IOCNR_HP_SET_CHANNEL 4
#define IOCNR_GET_BUS_ADDRESS 5
#define IOCNR_GET_VID_PID 6
#define IOCNR_SOFT_RESET 7
/* Get device_id string: */
#define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
/* The following ioctls were added for http://hpoj.sourceforge.net:
* Get two-int array:
* [0]=current protocol
* (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
* 3=USB_CLASS_PRINTER/1/3),
* [1]=supported protocol mask (mask&(1<<n)!=0 means
* USB_CLASS_PRINTER/1/n supported):
*/
#define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
/*
* Set protocol
* (arg: 1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
* 3=USB_CLASS_PRINTER/1/3):
*/
#define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
/* Set channel number (HP Vendor-specific command): */
#define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
/* Get two-int array: [0]=bus number, [1]=device address: */
#define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
/* Get two-int array: [0]=vendor ID, [1]=product ID: */
#define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
/* Perform class specific soft reset */
#define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
/*
* A DEVICE_ID string may include the printer's serial number.
* It should end with a semi-colon (';').
* An example from an HP 970C DeskJet printer is (this is one long string,
* with the serial number changed):
MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:Hewlett-Packard DeskJet 970C;SERN:US970CSEPROF;VSTATUS:$HB0$NC0,ff,DN,IDLE,CUT,K1,C0,DP,NR,KP000,CP027;VP:0800,FL,B0;VJ: ;
*/
/*
* USB Printer Requests
*/
#define USBLP_REQ_GET_ID 0x00
#define USBLP_REQ_GET_STATUS 0x01
#define USBLP_REQ_RESET 0x02
#define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST 0x00 /* HP Vendor-specific */
#define USBLP_MINORS 16
#define USBLP_MINOR_BASE 0
#define USBLP_CTL_TIMEOUT 5000 /* 5 seconds */
#define USBLP_FIRST_PROTOCOL 1
#define USBLP_LAST_PROTOCOL 3
#define USBLP_MAX_PROTOCOLS (USBLP_LAST_PROTOCOL+1)
/*
* some arbitrary status buffer size;
* need a status buffer that is allocated via kmalloc(), not on stack
*/
#define STATUS_BUF_SIZE 8
/*
* Locks down the locking order:
* ->wmut locks wstatus.
* ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
* [rw]status. We only touch status when we know the side idle.
* ->lock locks what interrupt accesses.
*/
struct usblp {
struct usb_device *dev; /* USB device */
struct mutex wmut;
struct mutex mut;
spinlock_t lock; /* locks rcomplete, wcomplete */
char *readbuf; /* read transfer_buffer */
char *statusbuf; /* status transfer_buffer */
struct usb_anchor urbs;
wait_queue_head_t rwait, wwait;
int readcount; /* Counter for reads */
int ifnum; /* Interface number */
struct usb_interface *intf; /* The interface */
/*
* Alternate-setting numbers and endpoints for each protocol
* (USB_CLASS_PRINTER/1/{index=1,2,3}) that the device supports:
*/
struct {
int alt_setting;
struct usb_endpoint_descriptor *epwrite;
struct usb_endpoint_descriptor *epread;
} protocol[USBLP_MAX_PROTOCOLS];
int current_protocol;
int minor; /* minor number of device */
int wcomplete, rcomplete;
int wstatus; /* bytes written or error */
int rstatus; /* bytes ready or error */
unsigned int quirks; /* quirks flags */
unsigned int flags; /* mode flags */
unsigned char used; /* True if open */
unsigned char present; /* True if not disconnected */
unsigned char bidir; /* interface is bidirectional */
unsigned char no_paper; /* Paper Out happened */
unsigned char *device_id_string; /* IEEE 1284 DEVICE ID string (ptr) */
/* first 2 bytes are (big-endian) length */
};
#ifdef DEBUG
static void usblp_dump(struct usblp *usblp)
{
struct device *dev = &usblp->intf->dev;
int p;
dev_dbg(dev, "usblp=0x%p\n", usblp);
dev_dbg(dev, "dev=0x%p\n", usblp->dev);
dev_dbg(dev, "present=%d\n", usblp->present);
dev_dbg(dev, "readbuf=0x%p\n", usblp->readbuf);
dev_dbg(dev, "readcount=%d\n", usblp->readcount);
dev_dbg(dev, "ifnum=%d\n", usblp->ifnum);
for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
dev_dbg(dev, "protocol[%d].alt_setting=%d\n", p,
usblp->protocol[p].alt_setting);
dev_dbg(dev, "protocol[%d].epwrite=%p\n", p,
usblp->protocol[p].epwrite);
dev_dbg(dev, "protocol[%d].epread=%p\n", p,
usblp->protocol[p].epread);
}
dev_dbg(dev, "current_protocol=%d\n", usblp->current_protocol);
dev_dbg(dev, "minor=%d\n", usblp->minor);
dev_dbg(dev, "wstatus=%d\n", usblp->wstatus);
dev_dbg(dev, "rstatus=%d\n", usblp->rstatus);
dev_dbg(dev, "quirks=%d\n", usblp->quirks);
dev_dbg(dev, "used=%d\n", usblp->used);
dev_dbg(dev, "bidir=%d\n", usblp->bidir);
dev_dbg(dev, "device_id_string=\"%s\"\n",
usblp->device_id_string ?
usblp->device_id_string + 2 :
(unsigned char *)"(null)");
}
#endif
/* Quirks: various printer quirks are handled by this table & its flags. */
struct quirk_printer_struct {
__u16 vendorId;
__u16 productId;
unsigned int quirks;
};
#define USBLP_QUIRK_BIDIR 0x1 /* reports bidir but requires unidirectional mode (no INs/reads) */
#define USBLP_QUIRK_USB_INIT 0x2 /* needs vendor USB init string */
#define USBLP_QUIRK_BAD_CLASS 0x4 /* descriptor uses vendor-specific Class or SubClass */
static const struct quirk_printer_struct quirk_printers[] = {
{ 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
{ 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
{ 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
{ 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
{ 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
{ 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
{ 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
{ 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
{ 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
{ 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
{ 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
{ 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
{ 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
{ 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <kernel@zut.de> */
{ 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
{ 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
{ 0, 0 }
};
static int usblp_wwait(struct usblp *usblp, int nonblock);
static int usblp_wtest(struct usblp *usblp, int nonblock);
static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
static int usblp_rtest(struct usblp *usblp, int nonblock);
static int usblp_submit_read(struct usblp *usblp);
static int usblp_select_alts(struct usblp *usblp);
static int usblp_set_protocol(struct usblp *usblp, int protocol);
static int usblp_cache_device_id_string(struct usblp *usblp);
/* forward reference to make our lives easier */
static struct usb_driver usblp_driver;
static DEFINE_MUTEX(usblp_mutex); /* locks the existence of usblp's */
/*
* Functions for usblp control messages.
*/
static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
{
int retval;
int index = usblp->ifnum;
/* High byte has the interface index.
Low byte has the alternate setting.
*/
if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS))
index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
retval = usb_control_msg(usblp->dev,
dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
request, type | dir | recip, value, index, buf, len, USBLP_CTL_TIMEOUT);
dev_dbg(&usblp->intf->dev,
"usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d\n",
request, !!dir, recip, value, index, len, retval);
return retval < 0 ? retval : 0;
}
#define usblp_read_status(usblp, status)\
usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
#define usblp_get_id(usblp, config, id, maxlen)\
usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
#define usblp_reset(usblp)\
usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
static int usblp_hp_channel_change_request(struct usblp *usblp, int channel, u8 *new_channel)
{
u8 *buf;
int ret;
buf = kzalloc(1, GFP_KERNEL);
if (!buf)
return -ENOMEM;
ret = usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST,
USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE,
channel, buf, 1);
if (ret == 0)
*new_channel = buf[0];
kfree(buf);
return ret;
}
/*
* See the description for usblp_select_alts() below for the usage
* explanation. Look into your /sys/kernel/debug/usb/devices and dmesg in
* case of any trouble.
*/
static int proto_bias = -1;
/*
* URB callback.
*/
static void usblp_bulk_read(struct urb *urb)
{
struct usblp *usblp = urb->context;
int status = urb->status;
unsigned long flags;
if (usblp->present && usblp->used) {
if (status)
printk(KERN_WARNING "usblp%d: "
"nonzero read bulk status received: %d\n",
usblp->minor, status);
}
spin_lock_irqsave(&usblp->lock, flags);
if (status < 0)
usblp->rstatus = status;
else
usblp->rstatus = urb->actual_length;
usblp->rcomplete = 1;
wake_up(&usblp->rwait);
spin_unlock_irqrestore(&usblp->lock, flags);
usb_free_urb(urb);
}
static void usblp_bulk_write(struct urb *urb)
{
struct usblp *usblp = urb->context;
int status = urb->status;
unsigned long flags;
if (usblp->present && usblp->used) {
if (status)
printk(KERN_WARNING "usblp%d: "
"nonzero write bulk status received: %d\n",
usblp->minor, status);
}
spin_lock_irqsave(&usblp->lock, flags);
if (status < 0)
usblp->wstatus = status;
else
usblp->wstatus = urb->actual_length;
usblp->no_paper = 0;
usblp->wcomplete = 1;
wake_up(&usblp->wwait);
spin_unlock_irqrestore(&usblp->lock, flags);
usb_free_urb(urb);
}
/*
* Get and print printer errors.
*/
static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
static int usblp_check_status(struct usblp *usblp, int err)
{
unsigned char status, newerr = 0;
int error;
mutex_lock(&usblp->mut);
if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
mutex_unlock(&usblp->mut);
printk_ratelimited(KERN_ERR
"usblp%d: error %d reading printer status\n",
usblp->minor, error);
return 0;
}
status = *usblp->statusbuf;
mutex_unlock(&usblp->mut);
if (~status & LP_PERRORP)
newerr = 3;
if (status & LP_POUTPA)
newerr = 1;
if (~status & LP_PSELECD)
newerr = 2;
if (newerr != err) {
printk(KERN_INFO "usblp%d: %s\n",
usblp->minor, usblp_messages[newerr]);
}
return newerr;
}
static int handle_bidir(struct usblp *usblp)
{
if (usblp->bidir && usblp->used) {
if (usblp_submit_read(usblp) < 0)
return -EIO;
}
return 0;
}
/*
* File op functions.
*/
static int usblp_open(struct inode *inode, struct file *file)
{
int minor = iminor(inode);
struct usblp *usblp;
struct usb_interface *intf;
int retval;
if (minor < 0)
return -ENODEV;
mutex_lock(&usblp_mutex);
retval = -ENODEV;
intf = usb_find_interface(&usblp_driver, minor);
if (!intf)
goto out;
usblp = usb_get_intfdata(intf);
if (!usblp || !usblp->dev || !usblp->present)
goto out;
retval = -EBUSY;
if (usblp->used)
goto out;
/*
* We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
* - We do not want persistent state which close(2) does not clear
* - It is not used anyway, according to CUPS people
*/
retval = usb_autopm_get_interface(intf);
if (retval < 0)
goto out;
usblp->used = 1;
file->private_data = usblp;
usblp->wcomplete = 1; /* we begin writeable */
usblp->wstatus = 0;
usblp->rcomplete = 0;
if (handle_bidir(usblp) < 0) {
usb_autopm_put_interface(intf);
usblp->used = 0;
file->private_data = NULL;
retval = -EIO;
}
out:
mutex_unlock(&usblp_mutex);
return retval;
}
static void usblp_cleanup(struct usblp *usblp)
{
printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
kfree(usblp->readbuf);
kfree(usblp->device_id_string);
kfree(usblp->statusbuf);
usb_put_intf(usblp->intf);
kfree(usblp);
}
static void usblp_unlink_urbs(struct usblp *usblp)
{
usb_kill_anchored_urbs(&usblp->urbs);
}
static int usblp_release(struct inode *inode, struct file *file)
{
struct usblp *usblp = file->private_data;
usblp->flags &= ~LP_ABORT;
mutex_lock(&usblp_mutex);
usblp->used = 0;
if (usblp->present)
usblp_unlink_urbs(usblp);
usb_autopm_put_interface(usblp->intf);
if (!usblp->present) /* finish cleanup from disconnect */
usblp_cleanup(usblp); /* any URBs must be dead */
mutex_unlock(&usblp_mutex);
return 0;
}
/* No kernel lock - fine */
static __poll_t usblp_poll(struct file *file, struct poll_table_struct *wait)
{
struct usblp *usblp = file->private_data;
__poll_t ret = 0;
unsigned long flags;
/* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
poll_wait(file, &usblp->rwait, wait);
poll_wait(file, &usblp->wwait, wait);
mutex_lock(&usblp->mut);
if (!usblp->present)
ret |= EPOLLHUP;
mutex_unlock(&usblp->mut);
spin_lock_irqsave(&usblp->lock, flags);
if (usblp->bidir && usblp->rcomplete)
ret |= EPOLLIN | EPOLLRDNORM;
if (usblp->no_paper || usblp->wcomplete)
ret |= EPOLLOUT | EPOLLWRNORM;
spin_unlock_irqrestore(&usblp->lock, flags);
return ret;
}
static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct usblp *usblp = file->private_data;
int length, err, i;
unsigned char newChannel;
int status;
int twoints[2];
int retval = 0;
mutex_lock(&usblp->mut);
if (!usblp->present) {
retval = -ENODEV;
goto done;
}
dev_dbg(&usblp->intf->dev,
"usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)\n", cmd,
_IOC_TYPE(cmd), _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
if (_IOC_TYPE(cmd) == 'P') /* new-style ioctl number */
switch (_IOC_NR(cmd)) {
case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
if (_IOC_DIR(cmd) != _IOC_READ) {
retval = -EINVAL;
goto done;
}
length = usblp_cache_device_id_string(usblp);
if (length < 0) {
retval = length;
goto done;
}
if (length > _IOC_SIZE(cmd))
length = _IOC_SIZE(cmd); /* truncate */
if (copy_to_user((void __user *) arg,
usblp->device_id_string,
(unsigned long) length)) {
retval = -EFAULT;
goto done;
}
break;
case IOCNR_GET_PROTOCOLS:
if (_IOC_DIR(cmd) != _IOC_READ ||
_IOC_SIZE(cmd) < sizeof(twoints)) {
retval = -EINVAL;
goto done;
}
twoints[0] = usblp->current_protocol;
twoints[1] = 0;
for (i = USBLP_FIRST_PROTOCOL;
i <= USBLP_LAST_PROTOCOL; i++) {
if (usblp->protocol[i].alt_setting >= 0)
twoints[1] |= (1<<i);
}
if (copy_to_user((void __user *)arg,
(unsigned char *)twoints,
sizeof(twoints))) {
retval = -EFAULT;
goto done;
}
break;
case IOCNR_SET_PROTOCOL:
if (_IOC_DIR(cmd) != _IOC_WRITE) {
retval = -EINVAL;
goto done;
}
#ifdef DEBUG
if (arg == -10) {
usblp_dump(usblp);
break;
}
#endif
usblp_unlink_urbs(usblp);
retval = usblp_set_protocol(usblp, arg);
if (retval < 0) {
usblp_set_protocol(usblp,
usblp->current_protocol);
}
break;
case IOCNR_HP_SET_CHANNEL:
if (_IOC_DIR(cmd) != _IOC_WRITE ||
le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
usblp->quirks & USBLP_QUIRK_BIDIR) {
retval = -EINVAL;
goto done;
}
err = usblp_hp_channel_change_request(usblp,
arg, &newChannel);
if (err < 0) {
dev_err(&usblp->dev->dev,
"usblp%d: error = %d setting "
"HP channel\n",
usblp->minor, err);
retval = -EIO;
goto done;
}
dev_dbg(&usblp->intf->dev,
"usblp%d requested/got HP channel %ld/%d\n",
usblp->minor, arg, newChannel);
break;
case IOCNR_GET_BUS_ADDRESS:
if (_IOC_DIR(cmd) != _IOC_READ ||
_IOC_SIZE(cmd) < sizeof(twoints)) {
retval = -EINVAL;
goto done;
}
twoints[0] = usblp->dev->bus->busnum;
twoints[1] = usblp->dev->devnum;
if (copy_to_user((void __user *)arg,
(unsigned char *)twoints,
sizeof(twoints))) {
retval = -EFAULT;
goto done;
}
dev_dbg(&usblp->intf->dev,
"usblp%d is bus=%d, device=%d\n",
usblp->minor, twoints[0], twoints[1]);
break;
case IOCNR_GET_VID_PID:
if (_IOC_DIR(cmd) != _IOC_READ ||
_IOC_SIZE(cmd) < sizeof(twoints)) {
retval = -EINVAL;
goto done;
}
twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
if (copy_to_user((void __user *)arg,
(unsigned char *)twoints,
sizeof(twoints))) {
retval = -EFAULT;
goto done;
}
dev_dbg(&usblp->intf->dev,
"usblp%d is VID=0x%4.4X, PID=0x%4.4X\n",
usblp->minor, twoints[0], twoints[1]);
break;
case IOCNR_SOFT_RESET:
if (_IOC_DIR(cmd) != _IOC_NONE) {
retval = -EINVAL;
goto done;
}
retval = usblp_reset(usblp);
break;
default:
retval = -ENOTTY;
}
else /* old-style ioctl value */
switch (cmd) {
case LPGETSTATUS:
retval = usblp_read_status(usblp, usblp->statusbuf);
if (retval) {
printk_ratelimited(KERN_ERR "usblp%d:"
"failed reading printer status (%d)\n",
usblp->minor, retval);
retval = -EIO;
goto done;
}
status = *usblp->statusbuf;
if (copy_to_user((void __user *)arg, &status, sizeof(int)))
retval = -EFAULT;
break;
case LPABORT:
if (arg)
usblp->flags |= LP_ABORT;
else
usblp->flags &= ~LP_ABORT;
break;
default:
retval = -ENOTTY;
}
done:
mutex_unlock(&usblp->mut);
return retval;
}
static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
{
struct urb *urb;
char *writebuf;
writebuf = kmalloc(transfer_length, GFP_KERNEL);
if (writebuf == NULL)
return NULL;
urb = usb_alloc_urb(0, GFP_KERNEL);
if (urb == NULL) {
kfree(writebuf);
return NULL;
}
usb_fill_bulk_urb(urb, usblp->dev,
usb_sndbulkpipe(usblp->dev,
usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
writebuf, transfer_length, usblp_bulk_write, usblp);
urb->transfer_flags |= URB_FREE_BUFFER;
return urb;
}
static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
{
struct usblp *usblp = file->private_data;
struct urb *writeurb;
int rv;
int transfer_length;
ssize_t writecount = 0;
if (mutex_lock_interruptible(&usblp->wmut)) {
rv = -EINTR;
goto raise_biglock;
}
if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
goto raise_wait;
while (writecount < count) {
/*
* Step 1: Submit next block.
*/
if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
transfer_length = USBLP_BUF_SIZE;
rv = -ENOMEM;
writeurb = usblp_new_writeurb(usblp, transfer_length);
if (writeurb == NULL)
goto raise_urb;
usb_anchor_urb(writeurb, &usblp->urbs);
if (copy_from_user(writeurb->transfer_buffer,
buffer + writecount, transfer_length)) {
rv = -EFAULT;
goto raise_badaddr;
}
spin_lock_irq(&usblp->lock);
usblp->wcomplete = 0;
spin_unlock_irq(&usblp->lock);
if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
usblp->wstatus = 0;
spin_lock_irq(&usblp->lock);
usblp->no_paper = 0;
usblp->wcomplete = 1;
wake_up(&usblp->wwait);
spin_unlock_irq(&usblp->lock);
if (rv != -ENOMEM)
rv = -EIO;
goto raise_submit;
}
/*
* Step 2: Wait for transfer to end, collect results.
*/
rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
if (rv < 0) {
if (rv == -EAGAIN) {
/* Presume that it's going to complete well. */
writecount += transfer_length;
}
if (rv == -ENOSPC) {
spin_lock_irq(&usblp->lock);
usblp->no_paper = 1; /* Mark for poll(2) */
spin_unlock_irq(&usblp->lock);
writecount += transfer_length;
}
/* Leave URB dangling, to be cleaned on close. */
goto collect_error;
}
if (usblp->wstatus < 0) {
rv = -EIO;
goto collect_error;
}
/*
* This is critical: it must be our URB, not other writer's.
* The wmut exists mainly to cover us here.
*/
writecount += usblp->wstatus;
}
mutex_unlock(&usblp->wmut);
return writecount;
raise_submit:
raise_badaddr:
usb_unanchor_urb(writeurb);
usb_free_urb(writeurb);
raise_urb:
raise_wait:
collect_error: /* Out of raise sequence */
mutex_unlock(&usblp->wmut);
raise_biglock:
return writecount ? writecount : rv;
}
/*
* Notice that we fail to restart in a few cases: on EFAULT, on restart
* error, etc. This is the historical behaviour. In all such cases we return
* EIO, and applications loop in order to get the new read going.
*/
static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
{
struct usblp *usblp = file->private_data;
ssize_t count;
ssize_t avail;
int rv;
if (!usblp->bidir)
return -EINVAL;
rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
if (rv < 0)
return rv;
if (!usblp->present) {
count = -ENODEV;
goto done;
}
if ((avail = usblp->rstatus) < 0) {
printk(KERN_ERR "usblp%d: error %d reading from printer\n",
usblp->minor, (int)avail);
usblp_submit_read(usblp);
count = -EIO;
goto done;
}
count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
if (count != 0 &&
copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
count = -EFAULT;
goto done;
}
if ((usblp->readcount += count) == avail) {
if (usblp_submit_read(usblp) < 0) {
/* We don't want to leak USB return codes into errno. */
if (count == 0)
count = -EIO;
goto done;
}
}
done:
mutex_unlock(&usblp->mut);
return count;
}
/*
* Wait for the write path to come idle.
* This is called under the ->wmut, so the idle path stays idle.
*
* Our write path has a peculiar property: it does not buffer like a tty,
* but waits for the write to succeed. This allows our ->release to bug out
* without waiting for writes to drain. But it obviously does not work
* when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
* select(2) or poll(2) to wait for the buffer to drain before closing.
* Alternatively, set blocking mode with fcntl and issue a zero-size write.
*/
static int usblp_wwait(struct usblp *usblp, int nonblock)
{
DECLARE_WAITQUEUE(waita, current);
int rc;
int err = 0;
add_wait_queue(&usblp->wwait, &waita);
for (;;) {
if (mutex_lock_interruptible(&usblp->mut)) {
rc = -EINTR;
break;
}
set_current_state(TASK_INTERRUPTIBLE);
rc = usblp_wtest(usblp, nonblock);
mutex_unlock(&usblp->mut);
if (rc <= 0)
break;
if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
if (usblp->flags & LP_ABORT) {
err = usblp_check_status(usblp, err);
if (err == 1) { /* Paper out */
rc = -ENOSPC;
break;
}
} else {
/* Prod the printer, Gentoo#251237. */
mutex_lock(&usblp->mut);
usblp_read_status(usblp, usblp->statusbuf);
mutex_unlock(&usblp->mut);
}
}
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&usblp->wwait, &waita);
return rc;
}
static int usblp_wtest(struct usblp *usblp, int nonblock)
{
unsigned long flags;
if (!usblp->present)
return -ENODEV;
if (signal_pending(current))
return -EINTR;
spin_lock_irqsave(&usblp->lock, flags);
if (usblp->wcomplete) {
spin_unlock_irqrestore(&usblp->lock, flags);
return 0;
}
spin_unlock_irqrestore(&usblp->lock, flags);
if (nonblock)
return -EAGAIN;
return 1;
}
/*
* Wait for read bytes to become available. This probably should have been
* called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
* name for functions which lock and return.
*
* We do not use wait_event_interruptible because it makes locking iffy.
*/
static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
{
DECLARE_WAITQUEUE(waita, current);
int rc;
add_wait_queue(&usblp->rwait, &waita);
for (;;) {
if (mutex_lock_interruptible(&usblp->mut)) {
rc = -EINTR;
break;
}
set_current_state(TASK_INTERRUPTIBLE);
if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
mutex_unlock(&usblp->mut);
break;
}
if (rc == 0) /* Keep it locked */
break;
mutex_unlock(&usblp->mut);
schedule();
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&usblp->rwait, &waita);
return rc;
}
static int usblp_rtest(struct usblp *usblp, int nonblock)
{
unsigned long flags;
if (!usblp->present)
return -ENODEV;
if (signal_pending(current))
return -EINTR;
spin_lock_irqsave(&usblp->lock, flags);
if (usblp->rcomplete) {
spin_unlock_irqrestore(&usblp->lock, flags);
return 0;
}
spin_unlock_irqrestore(&usblp->lock, flags);
if (nonblock)
return -EAGAIN;
return 1;
}
/*
* Please check ->bidir and other such things outside for now.
*/
static int usblp_submit_read(struct usblp *usblp)
{
struct urb *urb;
unsigned long flags;
int rc;
rc = -ENOMEM;
urb = usb_alloc_urb(0, GFP_KERNEL);
if (urb == NULL)
goto raise_urb;
usb_fill_bulk_urb(urb, usblp->dev,
usb_rcvbulkpipe(usblp->dev,
usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
usblp->readbuf, USBLP_BUF_SIZE_IN,
usblp_bulk_read, usblp);
usb_anchor_urb(urb, &usblp->urbs);
spin_lock_irqsave(&usblp->lock, flags);
usblp->readcount = 0; /* XXX Why here? */
usblp->rcomplete = 0;
spin_unlock_irqrestore(&usblp->lock, flags);
if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
dev_dbg(&usblp->intf->dev, "error submitting urb (%d)\n", rc);
spin_lock_irqsave(&usblp->lock, flags);
usblp->rstatus = rc;
usblp->rcomplete = 1;
spin_unlock_irqrestore(&usblp->lock, flags);
goto raise_submit;
}
return 0;
raise_submit:
usb_unanchor_urb(urb);
usb_free_urb(urb);
raise_urb:
return rc;
}
/*
* Checks for printers that have quirks, such as requiring unidirectional
* communication but reporting bidirectional; currently some HP printers
* have this flaw (HP 810, 880, 895, etc.), or needing an init string
* sent at each open (like some Epsons).
* Returns 1 if found, 0 if not found.
*
* HP recommended that we use the bidirectional interface but
* don't attempt any bulk IN transfers from the IN endpoint.
* Here's some more detail on the problem:
* The problem is not that it isn't bidirectional though. The problem
* is that if you request a device ID, or status information, while
* the buffers are full, the return data will end up in the print data
* buffer. For example if you make sure you never request the device ID
* while you are sending print data, and you don't try to query the
* printer status every couple of milliseconds, you will probably be OK.
*/
static unsigned int usblp_quirks(__u16 vendor, __u16 product)
{
int i;
for (i = 0; quirk_printers[i].vendorId; i++) {
if (vendor == quirk_printers[i].vendorId &&
product == quirk_printers[i].productId)
return quirk_printers[i].quirks;
}
return 0;
}
static const struct file_operations usblp_fops = {
.owner = THIS_MODULE,
.read = usblp_read,
.write = usblp_write,
.poll = usblp_poll,
.unlocked_ioctl = usblp_ioctl,
.compat_ioctl = usblp_ioctl,
.open = usblp_open,
.release = usblp_release,
.llseek = noop_llseek,
};
static char *usblp_devnode(struct device *dev, umode_t *mode)
{
return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
}
static struct usb_class_driver usblp_class = {
.name = "lp%d",
.devnode = usblp_devnode,
.fops = &usblp_fops,
.minor_base = USBLP_MINOR_BASE,
};
static ssize_t ieee1284_id_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usblp *usblp = usb_get_intfdata(intf);
if (usblp->device_id_string[0] == 0 &&
usblp->device_id_string[1] == 0)
return 0;
return sprintf(buf, "%s", usblp->device_id_string+2);
}
static DEVICE_ATTR_RO(ieee1284_id);
static struct attribute *usblp_attrs[] = {
&dev_attr_ieee1284_id.attr,
NULL,
};
ATTRIBUTE_GROUPS(usblp);
static int usblp_probe(struct usb_interface *intf,
const struct usb_device_id *id)
{
struct usb_device *dev = interface_to_usbdev(intf);
struct usblp *usblp;
int protocol;
int retval;
/* Malloc and start initializing usblp structure so we can use it
* directly. */
usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
if (!usblp) {
retval = -ENOMEM;
goto abort_ret;
}
usblp->dev = dev;
mutex_init(&usblp->wmut);
mutex_init(&usblp->mut);
spin_lock_init(&usblp->lock);
init_waitqueue_head(&usblp->rwait);
init_waitqueue_head(&usblp->wwait);
init_usb_anchor(&usblp->urbs);
usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
usblp->intf = usb_get_intf(intf);
/* Malloc device ID string buffer to the largest expected length,
* since we can re-query it on an ioctl and a dynamic string
* could change in length. */
if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
retval = -ENOMEM;
goto abort;
}
/*
* Allocate read buffer. We somewhat wastefully
* malloc both regardless of bidirectionality, because the
* alternate setting can be changed later via an ioctl.
*/
if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
retval = -ENOMEM;
goto abort;
}
/* Allocate buffer for printer status */
usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
if (!usblp->statusbuf) {
retval = -ENOMEM;
goto abort;
}
/* Lookup quirks for this printer. */
usblp->quirks = usblp_quirks(
le16_to_cpu(dev->descriptor.idVendor),
le16_to_cpu(dev->descriptor.idProduct));
/* Analyze and pick initial alternate settings and endpoints. */
protocol = usblp_select_alts(usblp);
if (protocol < 0) {
dev_dbg(&intf->dev,
"incompatible printer-class device 0x%4.4X/0x%4.4X\n",
le16_to_cpu(dev->descriptor.idVendor),
le16_to_cpu(dev->descriptor.idProduct));
retval = -ENODEV;
goto abort;
}
/* Setup the selected alternate setting and endpoints. */
if (usblp_set_protocol(usblp, protocol) < 0) {
retval = -ENODEV; /* ->probe isn't ->ioctl */
goto abort;
}
/* Retrieve and store the device ID string. */
usblp_cache_device_id_string(usblp);
#ifdef DEBUG
usblp_check_status(usblp, 0);
#endif
usb_set_intfdata(intf, usblp);
usblp->present = 1;
retval = usb_register_dev(intf, &usblp_class);
if (retval) {
dev_err(&intf->dev,
"usblp: Not able to get a minor (base %u, slice default): %d\n",
USBLP_MINOR_BASE, retval);
goto abort_intfdata;
}
usblp->minor = intf->minor;
dev_info(&intf->dev,
"usblp%d: USB %sdirectional printer dev %d if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
usblp->ifnum,
usblp->protocol[usblp->current_protocol].alt_setting,
usblp->current_protocol,
le16_to_cpu(usblp->dev->descriptor.idVendor),
le16_to_cpu(usblp->dev->descriptor.idProduct));
return 0;
abort_intfdata:
usb_set_intfdata(intf, NULL);
abort:
kfree(usblp->readbuf);
kfree(usblp->statusbuf);
kfree(usblp->device_id_string);
usb_put_intf(usblp->intf);
kfree(usblp);
abort_ret:
return retval;
}
/*
* We are a "new" style driver with usb_device_id table,
* but our requirements are too intricate for simple match to handle.
*
* The "proto_bias" option may be used to specify the preferred protocol
* for all USB printers (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
* 3=USB_CLASS_PRINTER/1/3). If the device supports the preferred protocol,
* then we bind to it.
*
* The best interface for us is USB_CLASS_PRINTER/1/2, because it
* is compatible with a stream of characters. If we find it, we bind to it.
*
* Note that the people from hpoj.sourceforge.net need to be able to
* bind to USB_CLASS_PRINTER/1/3 (MLC/1284.4), so we provide them ioctls
* for this purpose.
*
* Failing USB_CLASS_PRINTER/1/2, we look for USB_CLASS_PRINTER/1/3,
* even though it's probably not stream-compatible, because this matches
* the behaviour of the old code.
*
* If nothing else, we bind to USB_CLASS_PRINTER/1/1
* - the unidirectional interface.
*/
static int usblp_select_alts(struct usblp *usblp)
{
struct usb_interface *if_alt;
struct usb_host_interface *ifd;
struct usb_endpoint_descriptor *epwrite, *epread;
int p, i;
int res;
if_alt = usblp->intf;
for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
usblp->protocol[p].alt_setting = -1;
/* Find out what we have. */
for (i = 0; i < if_alt->num_altsetting; i++) {
ifd = &if_alt->altsetting[i];
if (ifd->desc.bInterfaceClass != USB_CLASS_PRINTER ||
ifd->desc.bInterfaceSubClass != 1)
if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
continue;
if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
continue;
/* Look for the expected bulk endpoints. */
if (ifd->desc.bInterfaceProtocol > 1) {
res = usb_find_common_endpoints(ifd,
&epread, &epwrite, NULL, NULL);
} else {
epread = NULL;
res = usb_find_bulk_out_endpoint(ifd, &epwrite);
}
/* Ignore buggy hardware without the right endpoints. */
if (res)
continue;
/* Turn off reads for buggy bidirectional printers. */
if (usblp->quirks & USBLP_QUIRK_BIDIR) {
printk(KERN_INFO "usblp%d: Disabling reads from "
"problematic bidirectional printer\n",
usblp->minor);
epread = NULL;
}
usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
ifd->desc.bAlternateSetting;
usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
}
/* If our requested protocol is supported, then use it. */
if (proto_bias >= USBLP_FIRST_PROTOCOL &&
proto_bias <= USBLP_LAST_PROTOCOL &&
usblp->protocol[proto_bias].alt_setting != -1)
return proto_bias;
/* Ordering is important here. */
if (usblp->protocol[2].alt_setting != -1)
return 2;
if (usblp->protocol[1].alt_setting != -1)
return 1;
if (usblp->protocol[3].alt_setting != -1)
return 3;
/* If nothing is available, then don't bind to this device. */
return -1;
}
static int usblp_set_protocol(struct usblp *usblp, int protocol)
{
int r, alts;
if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
return -EINVAL;
/* Don't unnecessarily set the interface if there's a single alt. */
if (usblp->intf->num_altsetting > 1) {
alts = usblp->protocol[protocol].alt_setting;
if (alts < 0)
return -EINVAL;
r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
if (r < 0) {
printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
alts, usblp->ifnum);
return r;
}
}
usblp->bidir = (usblp->protocol[protocol].epread != NULL);
usblp->current_protocol = protocol;
dev_dbg(&usblp->intf->dev, "usblp%d set protocol %d\n",
usblp->minor, protocol);
return 0;
}
/* Retrieves and caches device ID string.
* Returns length, including length bytes but not null terminator.
* On error, returns a negative errno value. */
static int usblp_cache_device_id_string(struct usblp *usblp)
{
int err, length;
err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
if (err < 0) {
dev_dbg(&usblp->intf->dev,
"usblp%d: error = %d reading IEEE-1284 Device ID string\n",
usblp->minor, err);
usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
return -EIO;
}
/* First two bytes are length in big-endian.
* They count themselves, and we copy them into
* the user's buffer. */
length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
if (length < 2)
length = 2;
else if (length >= USBLP_DEVICE_ID_SIZE)
length = USBLP_DEVICE_ID_SIZE - 1;
usblp->device_id_string[length] = '\0';
dev_dbg(&usblp->intf->dev, "usblp%d Device ID string [len=%d]=\"%s\"\n",
usblp->minor, length, &usblp->device_id_string[2]);
return length;
}
static void usblp_disconnect(struct usb_interface *intf)
{
struct usblp *usblp = usb_get_intfdata(intf);
usb_deregister_dev(intf, &usblp_class);
if (!usblp || !usblp->dev) {
dev_err(&intf->dev, "bogus disconnect\n");
BUG();
}
mutex_lock(&usblp_mutex);
mutex_lock(&usblp->mut);
usblp->present = 0;
wake_up(&usblp->wwait);
wake_up(&usblp->rwait);
usb_set_intfdata(intf, NULL);
usblp_unlink_urbs(usblp);
mutex_unlock(&usblp->mut);
usb_poison_anchored_urbs(&usblp->urbs);
if (!usblp->used)
usblp_cleanup(usblp);
mutex_unlock(&usblp_mutex);
}
static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
{
struct usblp *usblp = usb_get_intfdata(intf);
usblp_unlink_urbs(usblp);
#if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
/* not strictly necessary, but just in case */
wake_up(&usblp->wwait);
wake_up(&usblp->rwait);
#endif
return 0;
}
static int usblp_resume(struct usb_interface *intf)
{
struct usblp *usblp = usb_get_intfdata(intf);
int r;
r = handle_bidir(usblp);
return r;
}
static const struct usb_device_id usblp_ids[] = {
{ USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 1) },
{ USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 2) },
{ USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 3) },
{ USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 1) },
{ USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 2) },
{ USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 3) },
{ USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, usblp_ids);
static struct usb_driver usblp_driver = {
.name = "usblp",
.probe = usblp_probe,
.disconnect = usblp_disconnect,
.suspend = usblp_suspend,
.resume = usblp_resume,
.id_table = usblp_ids,
.dev_groups = usblp_groups,
.supports_autosuspend = 1,
};
module_usb_driver(usblp_driver);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
module_param(proto_bias, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
MODULE_LICENSE("GPL");