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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/char/lp.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
Diffstat (limited to 'drivers/char/lp.c')
-rw-r--r--drivers/char/lp.c995
1 files changed, 995 insertions, 0 deletions
diff --git a/drivers/char/lp.c b/drivers/char/lp.c
new file mode 100644
index 000000000000..4dee945031d4
--- /dev/null
+++ b/drivers/char/lp.c
@@ -0,0 +1,995 @@
+/*
+ * Generic parallel printer driver
+ *
+ * Copyright (C) 1992 by Jim Weigand and Linus Torvalds
+ * Copyright (C) 1992,1993 by Michael K. Johnson
+ * - Thanks much to Gunter Windau for pointing out to me where the error
+ *   checking ought to be.
+ * Copyright (C) 1993 by Nigel Gamble (added interrupt code)
+ * Copyright (C) 1994 by Alan Cox (Modularised it)
+ * LPCAREFUL, LPABORT, LPGETSTATUS added by Chris Metcalf, metcalf@lcs.mit.edu
+ * Statistics and support for slow printers by Rob Janssen, rob@knoware.nl
+ * "lp=" command line parameters added by Grant Guenther, grant@torque.net
+ * lp_read (Status readback) support added by Carsten Gross,
+ *                                             carsten@sol.wohnheim.uni-ulm.de
+ * Support for parport by Philip Blundell <philb@gnu.org>
+ * Parport sharing hacking by Andrea Arcangeli
+ * Fixed kernel_(to/from)_user memory copy to check for errors
+ * 				by Riccardo Facchetti <fizban@tin.it>
+ * 22-JAN-1998  Added support for devfs  Richard Gooch <rgooch@atnf.csiro.au>
+ * Redesigned interrupt handling for handle printers with buggy handshake
+ *				by Andrea Arcangeli, 11 May 1998
+ * Full efficient handling of printer with buggy irq handshake (now I have
+ * understood the meaning of the strange handshake). This is done sending new
+ * characters if the interrupt is just happened, even if the printer say to
+ * be still BUSY. This is needed at least with Epson Stylus Color. To enable
+ * the new TRUST_IRQ mode read the `LP OPTIMIZATION' section below...
+ * Fixed the irq on the rising edge of the strobe case.
+ * Obsoleted the CAREFUL flag since a printer that doesn' t work with
+ * CAREFUL will block a bit after in lp_check_status().
+ *				Andrea Arcangeli, 15 Oct 1998
+ * Obsoleted and removed all the lowlevel stuff implemented in the last
+ * month to use the IEEE1284 functions (that handle the _new_ compatibilty
+ * mode fine).
+ */
+
+/* This driver should, in theory, work with any parallel port that has an
+ * appropriate low-level driver; all I/O is done through the parport
+ * abstraction layer.
+ *
+ * If this driver is built into the kernel, you can configure it using the
+ * kernel command-line.  For example:
+ *
+ *	lp=parport1,none,parport2	(bind lp0 to parport1, disable lp1 and
+ *					 bind lp2 to parport2)
+ *
+ *	lp=auto				(assign lp devices to all ports that
+ *				         have printers attached, as determined
+ *					 by the IEEE-1284 autoprobe)
+ * 
+ *	lp=reset			(reset the printer during 
+ *					 initialisation)
+ *
+ *	lp=off				(disable the printer driver entirely)
+ *
+ * If the driver is loaded as a module, similar functionality is available
+ * using module parameters.  The equivalent of the above commands would be:
+ *
+ *	# insmod lp.o parport=1,none,2
+ *
+ *	# insmod lp.o parport=auto
+ *
+ *	# insmod lp.o reset=1
+ */
+
+/* COMPATIBILITY WITH OLD KERNELS
+ *
+ * Under Linux 2.0 and previous versions, lp devices were bound to ports at
+ * particular I/O addresses, as follows:
+ *
+ *	lp0		0x3bc
+ *	lp1		0x378
+ *	lp2		0x278
+ *
+ * The new driver, by default, binds lp devices to parport devices as it
+ * finds them.  This means that if you only have one port, it will be bound
+ * to lp0 regardless of its I/O address.  If you need the old behaviour, you
+ * can force it using the parameters described above.
+ */
+
+/*
+ * The new interrupt handling code take care of the buggy handshake
+ * of some HP and Epson printer:
+ * ___
+ * ACK    _______________    ___________
+ *                       |__|
+ * ____
+ * BUSY   _________              _______
+ *                 |____________|
+ *
+ * I discovered this using the printer scanner that you can find at:
+ *
+ *	ftp://e-mind.com/pub/linux/pscan/
+ *
+ *					11 May 98, Andrea Arcangeli
+ *
+ * My printer scanner run on an Epson Stylus Color show that such printer
+ * generates the irq on the _rising_ edge of the STROBE. Now lp handle
+ * this case fine too.
+ *
+ *					15 Oct 1998, Andrea Arcangeli
+ *
+ * The so called `buggy' handshake is really the well documented
+ * compatibility mode IEEE1284 handshake. They changed the well known
+ * Centronics handshake acking in the middle of busy expecting to not
+ * break drivers or legacy application, while they broken linux lp
+ * until I fixed it reverse engineering the protocol by hand some
+ * month ago...
+ *
+ *                                     14 Dec 1998, Andrea Arcangeli
+ *
+ * Copyright (C) 2000 by Tim Waugh (added LPSETTIMEOUT ioctl)
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/sched.h>
+#include <linux/smp_lock.h>
+#include <linux/devfs_fs_kernel.h>
+#include <linux/slab.h>
+#include <linux/fcntl.h>
+#include <linux/delay.h>
+#include <linux/poll.h>
+#include <linux/console.h>
+#include <linux/device.h>
+#include <linux/wait.h>
+
+#include <linux/parport.h>
+#undef LP_STATS
+#include <linux/lp.h>
+
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+/* if you have more than 8 printers, remember to increase LP_NO */
+#define LP_NO 8
+
+/* ROUND_UP macro from fs/select.c */
+#define ROUND_UP(x,y) (((x)+(y)-1)/(y))
+
+static struct lp_struct lp_table[LP_NO];
+
+static unsigned int lp_count = 0;
+static struct class_simple *lp_class;
+
+#ifdef CONFIG_LP_CONSOLE
+static struct parport *console_registered; // initially NULL
+#endif /* CONFIG_LP_CONSOLE */
+
+#undef LP_DEBUG
+
+/* Bits used to manage claiming the parport device */
+#define LP_PREEMPT_REQUEST 1
+#define LP_PARPORT_CLAIMED 2
+
+/* --- low-level port access ----------------------------------- */
+
+#define r_dtr(x)	(parport_read_data(lp_table[(x)].dev->port))
+#define r_str(x)	(parport_read_status(lp_table[(x)].dev->port))
+#define w_ctr(x,y)	do { parport_write_control(lp_table[(x)].dev->port, (y)); } while (0)
+#define w_dtr(x,y)	do { parport_write_data(lp_table[(x)].dev->port, (y)); } while (0)
+
+/* Claim the parport or block trying unless we've already claimed it */
+static void lp_claim_parport_or_block(struct lp_struct *this_lp)
+{
+	if (!test_and_set_bit(LP_PARPORT_CLAIMED, &this_lp->bits)) {
+		parport_claim_or_block (this_lp->dev);
+	}
+}
+
+/* Claim the parport or block trying unless we've already claimed it */
+static void lp_release_parport(struct lp_struct *this_lp)
+{
+	if (test_and_clear_bit(LP_PARPORT_CLAIMED, &this_lp->bits)) {
+		parport_release (this_lp->dev);
+	}
+}
+
+
+
+static int lp_preempt(void *handle)
+{
+	struct lp_struct *this_lp = (struct lp_struct *)handle;
+	set_bit(LP_PREEMPT_REQUEST, &this_lp->bits);
+	return (1);
+}
+
+
+/* 
+ * Try to negotiate to a new mode; if unsuccessful negotiate to
+ * compatibility mode.  Return the mode we ended up in.
+ */
+static int lp_negotiate(struct parport * port, int mode)
+{
+	if (parport_negotiate (port, mode) != 0) {
+		mode = IEEE1284_MODE_COMPAT;
+		parport_negotiate (port, mode);
+	}
+
+	return (mode);
+}
+
+static int lp_reset(int minor)
+{
+	int retval;
+	lp_claim_parport_or_block (&lp_table[minor]);
+	w_ctr(minor, LP_PSELECP);
+	udelay (LP_DELAY);
+	w_ctr(minor, LP_PSELECP | LP_PINITP);
+	retval = r_str(minor);
+	lp_release_parport (&lp_table[minor]);
+	return retval;
+}
+
+static void lp_error (int minor)
+{
+	DEFINE_WAIT(wait);
+	int polling;
+
+	if (LP_F(minor) & LP_ABORT)
+		return;
+
+	polling = lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE;
+	if (polling) lp_release_parport (&lp_table[minor]);
+	prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
+	schedule_timeout(LP_TIMEOUT_POLLED);
+	finish_wait(&lp_table[minor].waitq, &wait);
+	if (polling) lp_claim_parport_or_block (&lp_table[minor]);
+	else parport_yield_blocking (lp_table[minor].dev);
+}
+
+static int lp_check_status(int minor)
+{
+	int error = 0;
+	unsigned int last = lp_table[minor].last_error;
+	unsigned char status = r_str(minor);
+	if ((status & LP_PERRORP) && !(LP_F(minor) & LP_CAREFUL))
+		/* No error. */
+		last = 0;
+	else if ((status & LP_POUTPA)) {
+		if (last != LP_POUTPA) {
+			last = LP_POUTPA;
+			printk(KERN_INFO "lp%d out of paper\n", minor);
+		}
+		error = -ENOSPC;
+	} else if (!(status & LP_PSELECD)) {
+		if (last != LP_PSELECD) {
+			last = LP_PSELECD;
+			printk(KERN_INFO "lp%d off-line\n", minor);
+		}
+		error = -EIO;
+	} else if (!(status & LP_PERRORP)) {
+		if (last != LP_PERRORP) {
+			last = LP_PERRORP;
+			printk(KERN_INFO "lp%d on fire\n", minor);
+		}
+		error = -EIO;
+	} else {
+		last = 0; /* Come here if LP_CAREFUL is set and no
+                             errors are reported. */
+	}
+
+	lp_table[minor].last_error = last;
+
+	if (last != 0)
+		lp_error(minor);
+
+	return error;
+}
+
+static int lp_wait_ready(int minor, int nonblock)
+{
+	int error = 0;
+
+	/* If we're not in compatibility mode, we're ready now! */
+	if (lp_table[minor].current_mode != IEEE1284_MODE_COMPAT) {
+	  return (0);
+	}
+
+	do {
+		error = lp_check_status (minor);
+		if (error && (nonblock || (LP_F(minor) & LP_ABORT)))
+			break;
+		if (signal_pending (current)) {
+			error = -EINTR;
+			break;
+		}
+	} while (error);
+	return error;
+}
+
+static ssize_t lp_write(struct file * file, const char __user * buf,
+		        size_t count, loff_t *ppos)
+{
+	unsigned int minor = iminor(file->f_dentry->d_inode);
+	struct parport *port = lp_table[minor].dev->port;
+	char *kbuf = lp_table[minor].lp_buffer;
+	ssize_t retv = 0;
+	ssize_t written;
+	size_t copy_size = count;
+	int nonblock = ((file->f_flags & O_NONBLOCK) ||
+			(LP_F(minor) & LP_ABORT));
+
+#ifdef LP_STATS
+	if (jiffies-lp_table[minor].lastcall > LP_TIME(minor))
+		lp_table[minor].runchars = 0;
+
+	lp_table[minor].lastcall = jiffies;
+#endif
+
+	/* Need to copy the data from user-space. */
+	if (copy_size > LP_BUFFER_SIZE)
+		copy_size = LP_BUFFER_SIZE;
+
+	if (down_interruptible (&lp_table[minor].port_mutex))
+		return -EINTR;
+
+	if (copy_from_user (kbuf, buf, copy_size)) {
+		retv = -EFAULT;
+		goto out_unlock;
+	}
+
+ 	/* Claim Parport or sleep until it becomes available
+ 	 */
+	lp_claim_parport_or_block (&lp_table[minor]);
+	/* Go to the proper mode. */
+	lp_table[minor].current_mode = lp_negotiate (port, 
+						     lp_table[minor].best_mode);
+
+	parport_set_timeout (lp_table[minor].dev,
+			     (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
+			      : lp_table[minor].timeout));
+
+	if ((retv = lp_wait_ready (minor, nonblock)) == 0)
+	do {
+		/* Write the data. */
+		written = parport_write (port, kbuf, copy_size);
+		if (written > 0) {
+			copy_size -= written;
+			count -= written;
+			buf  += written;
+			retv += written;
+		}
+
+		if (signal_pending (current)) {
+			if (retv == 0)
+				retv = -EINTR;
+
+			break;
+		}
+
+		if (copy_size > 0) {
+			/* incomplete write -> check error ! */
+			int error;
+
+			parport_negotiate (lp_table[minor].dev->port, 
+					   IEEE1284_MODE_COMPAT);
+			lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
+
+			error = lp_wait_ready (minor, nonblock);
+
+			if (error) {
+				if (retv == 0)
+					retv = error;
+				break;
+			} else if (nonblock) {
+				if (retv == 0)
+					retv = -EAGAIN;
+				break;
+			}
+
+			parport_yield_blocking (lp_table[minor].dev);
+			lp_table[minor].current_mode 
+			  = lp_negotiate (port, 
+					  lp_table[minor].best_mode);
+
+		} else if (need_resched())
+			schedule ();
+
+		if (count) {
+			copy_size = count;
+			if (copy_size > LP_BUFFER_SIZE)
+				copy_size = LP_BUFFER_SIZE;
+
+			if (copy_from_user(kbuf, buf, copy_size)) {
+				if (retv == 0)
+					retv = -EFAULT;
+				break;
+			}
+		}	
+	} while (count > 0);
+
+	if (test_and_clear_bit(LP_PREEMPT_REQUEST, 
+			       &lp_table[minor].bits)) {
+		printk(KERN_INFO "lp%d releasing parport\n", minor);
+		parport_negotiate (lp_table[minor].dev->port, 
+				   IEEE1284_MODE_COMPAT);
+		lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
+		lp_release_parport (&lp_table[minor]);
+	}
+out_unlock:
+	up (&lp_table[minor].port_mutex);
+
+ 	return retv;
+}
+
+#ifdef CONFIG_PARPORT_1284
+
+/* Status readback conforming to ieee1284 */
+static ssize_t lp_read(struct file * file, char __user * buf,
+		       size_t count, loff_t *ppos)
+{
+	DEFINE_WAIT(wait);
+	unsigned int minor=iminor(file->f_dentry->d_inode);
+	struct parport *port = lp_table[minor].dev->port;
+	ssize_t retval = 0;
+	char *kbuf = lp_table[minor].lp_buffer;
+	int nonblock = ((file->f_flags & O_NONBLOCK) ||
+			(LP_F(minor) & LP_ABORT));
+
+	if (count > LP_BUFFER_SIZE)
+		count = LP_BUFFER_SIZE;
+
+	if (down_interruptible (&lp_table[minor].port_mutex))
+		return -EINTR;
+
+	lp_claim_parport_or_block (&lp_table[minor]);
+
+	parport_set_timeout (lp_table[minor].dev,
+			     (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
+			      : lp_table[minor].timeout));
+
+	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
+	if (parport_negotiate (lp_table[minor].dev->port,
+			       IEEE1284_MODE_NIBBLE)) {
+		retval = -EIO;
+		goto out;
+	}
+
+	while (retval == 0) {
+		retval = parport_read (port, kbuf, count);
+
+		if (retval > 0)
+			break;
+
+		if (nonblock) {
+			retval = -EAGAIN;
+			break;
+		}
+
+		/* Wait for data. */
+
+		if (lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE) {
+			parport_negotiate (lp_table[minor].dev->port,
+					   IEEE1284_MODE_COMPAT);
+			lp_error (minor);
+			if (parport_negotiate (lp_table[minor].dev->port,
+					       IEEE1284_MODE_NIBBLE)) {
+				retval = -EIO;
+				goto out;
+			}
+		} else {
+			prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
+			schedule_timeout(LP_TIMEOUT_POLLED);
+			finish_wait(&lp_table[minor].waitq, &wait);
+		}
+
+		if (signal_pending (current)) {
+			retval = -ERESTARTSYS;
+			break;
+		}
+
+		cond_resched ();
+	}
+	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
+ out:
+	lp_release_parport (&lp_table[minor]);
+
+	if (retval > 0 && copy_to_user (buf, kbuf, retval))
+		retval = -EFAULT;
+
+	up (&lp_table[minor].port_mutex);
+
+	return retval;
+}
+
+#endif /* IEEE 1284 support */
+
+static int lp_open(struct inode * inode, struct file * file)
+{
+	unsigned int minor = iminor(inode);
+
+	if (minor >= LP_NO)
+		return -ENXIO;
+	if ((LP_F(minor) & LP_EXIST) == 0)
+		return -ENXIO;
+	if (test_and_set_bit(LP_BUSY_BIT_POS, &LP_F(minor)))
+		return -EBUSY;
+
+	/* If ABORTOPEN is set and the printer is offline or out of paper,
+	   we may still want to open it to perform ioctl()s.  Therefore we
+	   have commandeered O_NONBLOCK, even though it is being used in
+	   a non-standard manner.  This is strictly a Linux hack, and
+	   should most likely only ever be used by the tunelp application. */
+	if ((LP_F(minor) & LP_ABORTOPEN) && !(file->f_flags & O_NONBLOCK)) {
+		int status;
+		lp_claim_parport_or_block (&lp_table[minor]);
+		status = r_str(minor);
+		lp_release_parport (&lp_table[minor]);
+		if (status & LP_POUTPA) {
+			printk(KERN_INFO "lp%d out of paper\n", minor);
+			LP_F(minor) &= ~LP_BUSY;
+			return -ENOSPC;
+		} else if (!(status & LP_PSELECD)) {
+			printk(KERN_INFO "lp%d off-line\n", minor);
+			LP_F(minor) &= ~LP_BUSY;
+			return -EIO;
+		} else if (!(status & LP_PERRORP)) {
+			printk(KERN_ERR "lp%d printer error\n", minor);
+			LP_F(minor) &= ~LP_BUSY;
+			return -EIO;
+		}
+	}
+	lp_table[minor].lp_buffer = (char *) kmalloc(LP_BUFFER_SIZE, GFP_KERNEL);
+	if (!lp_table[minor].lp_buffer) {
+		LP_F(minor) &= ~LP_BUSY;
+		return -ENOMEM;
+	}
+	/* Determine if the peripheral supports ECP mode */
+	lp_claim_parport_or_block (&lp_table[minor]);
+	if ( (lp_table[minor].dev->port->modes & PARPORT_MODE_ECP) &&
+             !parport_negotiate (lp_table[minor].dev->port, 
+                                 IEEE1284_MODE_ECP)) {
+		printk (KERN_INFO "lp%d: ECP mode\n", minor);
+		lp_table[minor].best_mode = IEEE1284_MODE_ECP;
+	} else {
+		lp_table[minor].best_mode = IEEE1284_MODE_COMPAT;
+	}
+	/* Leave peripheral in compatibility mode */
+	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
+	lp_release_parport (&lp_table[minor]);
+	lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
+	return 0;
+}
+
+static int lp_release(struct inode * inode, struct file * file)
+{
+	unsigned int minor = iminor(inode);
+
+	lp_claim_parport_or_block (&lp_table[minor]);
+	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
+	lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
+	lp_release_parport (&lp_table[minor]);
+	kfree(lp_table[minor].lp_buffer);
+	lp_table[minor].lp_buffer = NULL;
+	LP_F(minor) &= ~LP_BUSY;
+	return 0;
+}
+
+static int lp_ioctl(struct inode *inode, struct file *file,
+		    unsigned int cmd, unsigned long arg)
+{
+	unsigned int minor = iminor(inode);
+	int status;
+	int retval = 0;
+	void __user *argp = (void __user *)arg;
+
+#ifdef LP_DEBUG
+	printk(KERN_DEBUG "lp%d ioctl, cmd: 0x%x, arg: 0x%lx\n", minor, cmd, arg);
+#endif
+	if (minor >= LP_NO)
+		return -ENODEV;
+	if ((LP_F(minor) & LP_EXIST) == 0)
+		return -ENODEV;
+	switch ( cmd ) {
+		struct timeval par_timeout;
+		long to_jiffies;
+
+		case LPTIME:
+			LP_TIME(minor) = arg * HZ/100;
+			break;
+		case LPCHAR:
+			LP_CHAR(minor) = arg;
+			break;
+		case LPABORT:
+			if (arg)
+				LP_F(minor) |= LP_ABORT;
+			else
+				LP_F(minor) &= ~LP_ABORT;
+			break;
+		case LPABORTOPEN:
+			if (arg)
+				LP_F(minor) |= LP_ABORTOPEN;
+			else
+				LP_F(minor) &= ~LP_ABORTOPEN;
+			break;
+		case LPCAREFUL:
+			if (arg)
+				LP_F(minor) |= LP_CAREFUL;
+			else
+				LP_F(minor) &= ~LP_CAREFUL;
+			break;
+		case LPWAIT:
+			LP_WAIT(minor) = arg;
+			break;
+		case LPSETIRQ: 
+			return -EINVAL;
+			break;
+		case LPGETIRQ:
+			if (copy_to_user(argp, &LP_IRQ(minor),
+					sizeof(int)))
+				return -EFAULT;
+			break;
+		case LPGETSTATUS:
+			lp_claim_parport_or_block (&lp_table[minor]);
+			status = r_str(minor);
+			lp_release_parport (&lp_table[minor]);
+
+			if (copy_to_user(argp, &status, sizeof(int)))
+				return -EFAULT;
+			break;
+		case LPRESET:
+			lp_reset(minor);
+			break;
+#ifdef LP_STATS
+		case LPGETSTATS:
+			if (copy_to_user(argp, &LP_STAT(minor),
+					sizeof(struct lp_stats)))
+				return -EFAULT;
+			if (capable(CAP_SYS_ADMIN))
+				memset(&LP_STAT(minor), 0,
+						sizeof(struct lp_stats));
+			break;
+#endif
+ 		case LPGETFLAGS:
+ 			status = LP_F(minor);
+			if (copy_to_user(argp, &status, sizeof(int)))
+				return -EFAULT;
+			break;
+
+		case LPSETTIMEOUT:
+			if (copy_from_user (&par_timeout, argp,
+					    sizeof (struct timeval))) {
+				return -EFAULT;
+			}
+			/* Convert to jiffies, place in lp_table */
+			if ((par_timeout.tv_sec < 0) ||
+			    (par_timeout.tv_usec < 0)) {
+				return -EINVAL;
+			}
+			to_jiffies = ROUND_UP(par_timeout.tv_usec, 1000000/HZ);
+			to_jiffies += par_timeout.tv_sec * (long) HZ;
+			if (to_jiffies <= 0) {
+				return -EINVAL;
+			}
+			lp_table[minor].timeout = to_jiffies;
+			break;
+
+		default:
+			retval = -EINVAL;
+	}
+	return retval;
+}
+
+static struct file_operations lp_fops = {
+	.owner		= THIS_MODULE,
+	.write		= lp_write,
+	.ioctl		= lp_ioctl,
+	.open		= lp_open,
+	.release	= lp_release,
+#ifdef CONFIG_PARPORT_1284
+	.read		= lp_read,
+#endif
+};
+
+/* --- support for console on the line printer ----------------- */
+
+#ifdef CONFIG_LP_CONSOLE
+
+#define CONSOLE_LP 0
+
+/* If the printer is out of paper, we can either lose the messages or
+ * stall until the printer is happy again.  Define CONSOLE_LP_STRICT
+ * non-zero to get the latter behaviour. */
+#define CONSOLE_LP_STRICT 1
+
+/* The console must be locked when we get here. */
+
+static void lp_console_write (struct console *co, const char *s,
+			      unsigned count)
+{
+	struct pardevice *dev = lp_table[CONSOLE_LP].dev;
+	struct parport *port = dev->port;
+	ssize_t written;
+
+	if (parport_claim (dev))
+		/* Nothing we can do. */
+		return;
+
+	parport_set_timeout (dev, 0);
+
+	/* Go to compatibility mode. */
+	parport_negotiate (port, IEEE1284_MODE_COMPAT);
+
+	do {
+		/* Write the data, converting LF->CRLF as we go. */
+		ssize_t canwrite = count;
+		char *lf = memchr (s, '\n', count);
+		if (lf)
+			canwrite = lf - s;
+
+		if (canwrite > 0) {
+			written = parport_write (port, s, canwrite);
+
+			if (written <= 0)
+				continue;
+
+			s += written;
+			count -= written;
+			canwrite -= written;
+		}
+
+		if (lf && canwrite <= 0) {
+			const char *crlf = "\r\n";
+			int i = 2;
+
+			/* Dodge the original '\n', and put '\r\n' instead. */
+			s++;
+			count--;
+			do {
+				written = parport_write (port, crlf, i);
+				if (written > 0)
+					i -= written, crlf += written;
+			} while (i > 0 && (CONSOLE_LP_STRICT || written > 0));
+		}
+	} while (count > 0 && (CONSOLE_LP_STRICT || written > 0));
+
+	parport_release (dev);
+}
+
+static struct console lpcons = {
+	.name		= "lp",
+	.write		= lp_console_write,
+	.flags		= CON_PRINTBUFFER,
+};
+
+#endif /* console on line printer */
+
+/* --- initialisation code ------------------------------------- */
+
+static int parport_nr[LP_NO] = { [0 ... LP_NO-1] = LP_PARPORT_UNSPEC };
+static char *parport[LP_NO] = { NULL,  };
+static int reset = 0;
+
+module_param_array(parport, charp, NULL, 0);
+module_param(reset, bool, 0);
+
+#ifndef MODULE
+static int __init lp_setup (char *str)
+{
+	static int parport_ptr; // initially zero
+	int x;
+
+	if (get_option (&str, &x)) {
+		if (x == 0) {
+			/* disable driver on "lp=" or "lp=0" */
+			parport_nr[0] = LP_PARPORT_OFF;
+		} else {
+			printk(KERN_WARNING "warning: 'lp=0x%x' is deprecated, ignored\n", x);
+			return 0;
+		}
+	} else if (!strncmp(str, "parport", 7)) {
+		int n = simple_strtoul(str+7, NULL, 10);
+		if (parport_ptr < LP_NO)
+			parport_nr[parport_ptr++] = n;
+		else
+			printk(KERN_INFO "lp: too many ports, %s ignored.\n",
+			       str);
+	} else if (!strcmp(str, "auto")) {
+		parport_nr[0] = LP_PARPORT_AUTO;
+	} else if (!strcmp(str, "none")) {
+		parport_nr[parport_ptr++] = LP_PARPORT_NONE;
+	} else if (!strcmp(str, "reset")) {
+		reset = 1;
+	}
+	return 1;
+}
+#endif
+
+static int lp_register(int nr, struct parport *port)
+{
+	lp_table[nr].dev = parport_register_device(port, "lp", 
+						   lp_preempt, NULL, NULL, 0,
+						   (void *) &lp_table[nr]);
+	if (lp_table[nr].dev == NULL)
+		return 1;
+	lp_table[nr].flags |= LP_EXIST;
+
+	if (reset)
+		lp_reset(nr);
+
+	class_simple_device_add(lp_class, MKDEV(LP_MAJOR, nr), NULL,
+				"lp%d", nr);
+	devfs_mk_cdev(MKDEV(LP_MAJOR, nr), S_IFCHR | S_IRUGO | S_IWUGO,
+			"printers/%d", nr);
+
+	printk(KERN_INFO "lp%d: using %s (%s).\n", nr, port->name, 
+	       (port->irq == PARPORT_IRQ_NONE)?"polling":"interrupt-driven");
+
+#ifdef CONFIG_LP_CONSOLE
+	if (!nr) {
+		if (port->modes & PARPORT_MODE_SAFEININT) {
+			register_console (&lpcons);
+			console_registered = port;
+			printk (KERN_INFO "lp%d: console ready\n", CONSOLE_LP);
+		} else
+			printk (KERN_ERR "lp%d: cannot run console on %s\n",
+				CONSOLE_LP, port->name);
+	}
+#endif
+
+	return 0;
+}
+
+static void lp_attach (struct parport *port)
+{
+	unsigned int i;
+
+	switch (parport_nr[0])
+	{
+	case LP_PARPORT_UNSPEC:
+	case LP_PARPORT_AUTO:
+		if (parport_nr[0] == LP_PARPORT_AUTO &&
+		    port->probe_info[0].class != PARPORT_CLASS_PRINTER)
+			return;
+		if (lp_count == LP_NO) {
+			printk(KERN_INFO "lp: ignoring parallel port (max. %d)\n",LP_NO);
+			return;
+		}
+		if (!lp_register(lp_count, port))
+			lp_count++;
+		break;
+
+	default:
+		for (i = 0; i < LP_NO; i++) {
+			if (port->number == parport_nr[i]) {
+				if (!lp_register(i, port))
+					lp_count++;
+				break;
+			}
+		}
+		break;
+	}
+}
+
+static void lp_detach (struct parport *port)
+{
+	/* Write this some day. */
+#ifdef CONFIG_LP_CONSOLE
+	if (console_registered == port) {
+		unregister_console (&lpcons);
+		console_registered = NULL;
+	}
+#endif /* CONFIG_LP_CONSOLE */
+}
+
+static struct parport_driver lp_driver = {
+	.name = "lp",
+	.attach = lp_attach,
+	.detach = lp_detach,
+};
+
+static int __init lp_init (void)
+{
+	int i, err = 0;
+
+	if (parport_nr[0] == LP_PARPORT_OFF)
+		return 0;
+
+	for (i = 0; i < LP_NO; i++) {
+		lp_table[i].dev = NULL;
+		lp_table[i].flags = 0;
+		lp_table[i].chars = LP_INIT_CHAR;
+		lp_table[i].time = LP_INIT_TIME;
+		lp_table[i].wait = LP_INIT_WAIT;
+		lp_table[i].lp_buffer = NULL;
+#ifdef LP_STATS
+		lp_table[i].lastcall = 0;
+		lp_table[i].runchars = 0;
+		memset (&lp_table[i].stats, 0, sizeof (struct lp_stats));
+#endif
+		lp_table[i].last_error = 0;
+		init_waitqueue_head (&lp_table[i].waitq);
+		init_waitqueue_head (&lp_table[i].dataq);
+		init_MUTEX (&lp_table[i].port_mutex);
+		lp_table[i].timeout = 10 * HZ;
+	}
+
+	if (register_chrdev (LP_MAJOR, "lp", &lp_fops)) {
+		printk (KERN_ERR "lp: unable to get major %d\n", LP_MAJOR);
+		return -EIO;
+	}
+
+	devfs_mk_dir("printers");
+	lp_class = class_simple_create(THIS_MODULE, "printer");
+	if (IS_ERR(lp_class)) {
+		err = PTR_ERR(lp_class);
+		goto out_devfs;
+	}
+
+	if (parport_register_driver (&lp_driver)) {
+		printk (KERN_ERR "lp: unable to register with parport\n");
+		err = -EIO;
+		goto out_class;
+	}
+
+	if (!lp_count) {
+		printk (KERN_INFO "lp: driver loaded but no devices found\n");
+#ifndef CONFIG_PARPORT_1284
+		if (parport_nr[0] == LP_PARPORT_AUTO)
+			printk (KERN_INFO "lp: (is IEEE 1284 support enabled?)\n");
+#endif
+	}
+
+	return 0;
+
+out_class:
+	class_simple_destroy(lp_class);
+out_devfs:
+	devfs_remove("printers");
+	unregister_chrdev(LP_MAJOR, "lp");
+	return err;
+}
+
+static int __init lp_init_module (void)
+{
+	if (parport[0]) {
+		/* The user gave some parameters.  Let's see what they were.  */
+		if (!strncmp(parport[0], "auto", 4))
+			parport_nr[0] = LP_PARPORT_AUTO;
+		else {
+			int n;
+			for (n = 0; n < LP_NO && parport[n]; n++) {
+				if (!strncmp(parport[n], "none", 4))
+					parport_nr[n] = LP_PARPORT_NONE;
+				else {
+					char *ep;
+					unsigned long r = simple_strtoul(parport[n], &ep, 0);
+					if (ep != parport[n]) 
+						parport_nr[n] = r;
+					else {
+						printk(KERN_ERR "lp: bad port specifier `%s'\n", parport[n]);
+						return -ENODEV;
+					}
+				}
+			}
+		}
+	}
+
+	return lp_init();
+}
+
+static void lp_cleanup_module (void)
+{
+	unsigned int offset;
+
+	parport_unregister_driver (&lp_driver);
+
+#ifdef CONFIG_LP_CONSOLE
+	unregister_console (&lpcons);
+#endif
+
+	unregister_chrdev(LP_MAJOR, "lp");
+	for (offset = 0; offset < LP_NO; offset++) {
+		if (lp_table[offset].dev == NULL)
+			continue;
+		parport_unregister_device(lp_table[offset].dev);
+		devfs_remove("printers/%d", offset);
+		class_simple_device_remove(MKDEV(LP_MAJOR, offset));
+	}
+	devfs_remove("printers");
+	class_simple_destroy(lp_class);
+}
+
+__setup("lp=", lp_setup);
+module_init(lp_init_module);
+module_exit(lp_cleanup_module);
+
+MODULE_ALIAS_CHARDEV_MAJOR(LP_MAJOR);
+MODULE_LICENSE("GPL");