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WSL2-Linux-Kernel
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WSL2-Linux-Kernel/drivers/char/lp.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* 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/errno.h>
#include <linux/kernel.h>
#include <linux/major.h>
#include <linux/sched/signal.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/jiffies.h>
#include <linux/mutex.h>
#include <linux/compat.h>
#include <linux/parport.h>
#undef LP_STATS
#include <linux/lp.h>
#include <asm/irq.h>
#include <linux/uaccess.h>
/* if you have more than 8 printers, remember to increase LP_NO */
#define LP_NO 8
static DEFINE_MUTEX(lp_mutex);
static struct lp_struct lp_table[LP_NO];
static int port_num[LP_NO];
static unsigned int lp_count = 0;
static struct class *lp_class;
#ifdef CONFIG_LP_CONSOLE
static struct parport *console_registered;
#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_inode(file));
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 (time_after(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 (mutex_lock_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:
mutex_unlock(&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_inode(file));
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 (mutex_lock_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;
mutex_unlock(&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);
int ret = 0;
mutex_lock(&lp_mutex);
if (minor >= LP_NO) {
ret = -ENXIO;
goto out;
}
if ((LP_F(minor) & LP_EXIST) == 0) {
ret = -ENXIO;
goto out;
}
if (test_and_set_bit(LP_BUSY_BIT_POS, &LP_F(minor))) {
ret = -EBUSY;
goto out;
}
/* 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;
ret = -ENOSPC;
goto out;
} else if (!(status & LP_PSELECD)) {
printk(KERN_INFO "lp%d off-line\n", minor);
LP_F(minor) &= ~LP_BUSY;
ret = -EIO;
goto out;
} else if (!(status & LP_PERRORP)) {
printk(KERN_ERR "lp%d printer error\n", minor);
LP_F(minor) &= ~LP_BUSY;
ret = -EIO;
goto out;
}
}
lp_table[minor].lp_buffer = kmalloc(LP_BUFFER_SIZE, GFP_KERNEL);
if (!lp_table[minor].lp_buffer) {
LP_F(minor) &= ~LP_BUSY;
ret = -ENOMEM;
goto out;
}
/* 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;
out:
mutex_unlock(&lp_mutex);
return ret;
}
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_do_ioctl(unsigned int minor, unsigned int cmd,
unsigned long arg, void __user *argp)
{
int status;
int retval = 0;
#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 ) {
case LPTIME:
if (arg > UINT_MAX / HZ)
return -EINVAL;
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:
if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
return -EINTR;
lp_claim_parport_or_block(&lp_table[minor]);
status = r_str(minor);
lp_release_parport(&lp_table[minor]);
mutex_unlock(&lp_table[minor].port_mutex);
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;
default:
retval = -EINVAL;
}
return retval;
}
static int lp_set_timeout(unsigned int minor, s64 tv_sec, long tv_usec)
{
long to_jiffies;
/* Convert to jiffies, place in lp_table */
if (tv_sec < 0 || tv_usec < 0)
return -EINVAL;
/*
* we used to not check, so let's not make this fatal,
* but deal with user space passing a 32-bit tv_nsec in
* a 64-bit field, capping the timeout to 1 second
* worth of microseconds, and capping the total at
* MAX_JIFFY_OFFSET.
*/
if (tv_usec > 999999)
tv_usec = 999999;
if (tv_sec >= MAX_SEC_IN_JIFFIES - 1) {
to_jiffies = MAX_JIFFY_OFFSET;
} else {
to_jiffies = DIV_ROUND_UP(tv_usec, 1000000/HZ);
to_jiffies += tv_sec * (long) HZ;
}
if (to_jiffies <= 0) {
return -EINVAL;
}
lp_table[minor].timeout = to_jiffies;
return 0;
}
static int lp_set_timeout32(unsigned int minor, void __user *arg)
{
s32 karg[2];
if (copy_from_user(karg, arg, sizeof(karg)))
return -EFAULT;
return lp_set_timeout(minor, karg[0], karg[1]);
}
static int lp_set_timeout64(unsigned int minor, void __user *arg)
{
s64 karg[2];
if (copy_from_user(karg, arg, sizeof(karg)))
return -EFAULT;
/* sparc64 suseconds_t is 32-bit only */
if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall())
karg[1] >>= 32;
return lp_set_timeout(minor, karg[0], karg[1]);
}
static long lp_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
unsigned int minor;
int ret;
minor = iminor(file_inode(file));
mutex_lock(&lp_mutex);
switch (cmd) {
case LPSETTIMEOUT_OLD:
if (BITS_PER_LONG == 32) {
ret = lp_set_timeout32(minor, (void __user *)arg);
break;
}
/* fall through - for 64-bit */
case LPSETTIMEOUT_NEW:
ret = lp_set_timeout64(minor, (void __user *)arg);
break;
default:
ret = lp_do_ioctl(minor, cmd, arg, (void __user *)arg);
break;
}
mutex_unlock(&lp_mutex);
return ret;
}
#ifdef CONFIG_COMPAT
static long lp_compat_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
unsigned int minor;
int ret;
minor = iminor(file_inode(file));
mutex_lock(&lp_mutex);
switch (cmd) {
case LPSETTIMEOUT_OLD:
if (!COMPAT_USE_64BIT_TIME) {
ret = lp_set_timeout32(minor, (void __user *)arg);
break;
}
/* fall through - for x32 mode */
case LPSETTIMEOUT_NEW:
ret = lp_set_timeout64(minor, (void __user *)arg);
break;
#ifdef LP_STATS
case LPGETSTATS:
/* FIXME: add an implementation if you set LP_STATS */
ret = -EINVAL;
break;
#endif
default:
ret = lp_do_ioctl(minor, cmd, arg, compat_ptr(arg));
break;
}
mutex_unlock(&lp_mutex);
return ret;
}
#endif
static const struct file_operations lp_fops = {
.owner = THIS_MODULE,
.write = lp_write,
.unlocked_ioctl = lp_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = lp_compat_ioctl,
#endif
.open = lp_open,
.release = lp_release,
#ifdef CONFIG_PARPORT_1284
.read = lp_read,
#endif
.llseek = noop_llseek,
};
/* --- 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];
static bool reset;
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;
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")) {
if (parport_ptr < LP_NO)
parport_nr[parport_ptr++] = LP_PARPORT_NONE;
else
printk(KERN_INFO "lp: too many ports, %s ignored.\n",
str);
} else if (!strcmp(str, "reset")) {
reset = true;
}
return 1;
}
#endif
static int lp_register(int nr, struct parport *port)
{
struct pardev_cb ppdev_cb;
memset(&ppdev_cb, 0, sizeof(ppdev_cb));
ppdev_cb.preempt = lp_preempt;
ppdev_cb.private = &lp_table[nr];
lp_table[nr].dev = parport_register_dev_model(port, "lp",
&ppdev_cb, nr);
if (lp_table[nr].dev == NULL)
return 1;
lp_table[nr].flags |= LP_EXIST;
if (reset)
lp_reset(nr);
device_create(lp_class, port->dev, MKDEV(LP_MAJOR, nr), NULL,
"lp%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
port_num[nr] = port->number;
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;
}
for (i = 0; i < LP_NO; i++)
if (port_num[i] == -1)
break;
if (!lp_register(i, 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)
{
int n;
/* Write this some day. */
#ifdef CONFIG_LP_CONSOLE
if (console_registered == port) {
unregister_console(&lpcons);
console_registered = NULL;
}
#endif /* CONFIG_LP_CONSOLE */
for (n = 0; n < LP_NO; n++) {
if (port_num[n] == port->number) {
port_num[n] = -1;
lp_count--;
device_destroy(lp_class, MKDEV(LP_MAJOR, n));
parport_unregister_device(lp_table[n].dev);
}
}
}
static struct parport_driver lp_driver = {
.name = "lp",
.match_port = lp_attach,
.detach = lp_detach,
.devmodel = true,
};
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);
mutex_init(&lp_table[i].port_mutex);
lp_table[i].timeout = 10 * HZ;
port_num[i] = -1;
}
if (register_chrdev(LP_MAJOR, "lp", &lp_fops)) {
printk(KERN_ERR "lp: unable to get major %d\n", LP_MAJOR);
return -EIO;
}
lp_class = class_create(THIS_MODULE, "printer");
if (IS_ERR(lp_class)) {
err = PTR_ERR(lp_class);
goto out_reg;
}
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_destroy(lp_class);
out_reg:
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)
{
parport_unregister_driver(&lp_driver);
#ifdef CONFIG_LP_CONSOLE
unregister_console(&lpcons);
#endif
unregister_chrdev(LP_MAJOR, "lp");
class_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");
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