diff options
Diffstat (limited to '')
-rw-r--r-- | drivers/char/ppdev.c | 878 |
1 files changed, 878 insertions, 0 deletions
diff --git a/drivers/char/ppdev.c b/drivers/char/ppdev.c new file mode 100644 index 000000000..38b46c7d1 --- /dev/null +++ b/drivers/char/ppdev.c @@ -0,0 +1,878 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * linux/drivers/char/ppdev.c + * + * This is the code behind /dev/parport* -- it allows a user-space + * application to use the parport subsystem. + * + * Copyright (C) 1998-2000, 2002 Tim Waugh <tim@cyberelk.net> + * + * A /dev/parportx device node represents an arbitrary device + * on port 'x'. The following operations are possible: + * + * open do nothing, set up default IEEE 1284 protocol to be COMPAT + * close release port and unregister device (if necessary) + * ioctl + * EXCL register device exclusively (may fail) + * CLAIM (register device first time) parport_claim_or_block + * RELEASE parport_release + * SETMODE set the IEEE 1284 protocol to use for read/write + * SETPHASE set the IEEE 1284 phase of a particular mode. Not to be + * confused with ioctl(fd, SETPHASER, &stun). ;-) + * DATADIR data_forward / data_reverse + * WDATA write_data + * RDATA read_data + * WCONTROL write_control + * RCONTROL read_control + * FCONTROL frob_control + * RSTATUS read_status + * NEGOT parport_negotiate + * YIELD parport_yield_blocking + * WCTLONIRQ on interrupt, set control lines + * CLRIRQ clear (and return) interrupt count + * SETTIME sets device timeout (struct timeval) + * GETTIME gets device timeout (struct timeval) + * GETMODES gets hardware supported modes (unsigned int) + * GETMODE gets the current IEEE1284 mode + * GETPHASE gets the current IEEE1284 phase + * GETFLAGS gets current (user-visible) flags + * SETFLAGS sets current (user-visible) flags + * read/write read or write in current IEEE 1284 protocol + * select wait for interrupt (in readfds) + * + * Changes: + * Added SETTIME/GETTIME ioctl, Fred Barnes, 1999. + * + * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 2000/08/25 + * - On error, copy_from_user and copy_to_user do not return -EFAULT, + * They return the positive number of bytes *not* copied due to address + * space errors. + * + * Added GETMODES/GETMODE/GETPHASE ioctls, Fred Barnes <frmb2@ukc.ac.uk>, 03/01/2001. + * Added GETFLAGS/SETFLAGS ioctls, Fred Barnes, 04/2001 + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/sched/signal.h> +#include <linux/device.h> +#include <linux/ioctl.h> +#include <linux/parport.h> +#include <linux/ctype.h> +#include <linux/poll.h> +#include <linux/slab.h> +#include <linux/major.h> +#include <linux/ppdev.h> +#include <linux/mutex.h> +#include <linux/uaccess.h> +#include <linux/compat.h> + +#define PP_VERSION "ppdev: user-space parallel port driver" +#define CHRDEV "ppdev" + +struct pp_struct { + struct pardevice *pdev; + wait_queue_head_t irq_wait; + atomic_t irqc; + unsigned int flags; + int irqresponse; + unsigned char irqctl; + struct ieee1284_info state; + struct ieee1284_info saved_state; + long default_inactivity; + int index; +}; + +/* should we use PARDEVICE_MAX here? */ +static struct device *devices[PARPORT_MAX]; + +static DEFINE_IDA(ida_index); + +/* pp_struct.flags bitfields */ +#define PP_CLAIMED (1<<0) +#define PP_EXCL (1<<1) + +/* Other constants */ +#define PP_INTERRUPT_TIMEOUT (10 * HZ) /* 10s */ +#define PP_BUFFER_SIZE 1024 +#define PARDEVICE_MAX 8 + +static DEFINE_MUTEX(pp_do_mutex); + +/* define fixed sized ioctl cmd for y2038 migration */ +#define PPGETTIME32 _IOR(PP_IOCTL, 0x95, s32[2]) +#define PPSETTIME32 _IOW(PP_IOCTL, 0x96, s32[2]) +#define PPGETTIME64 _IOR(PP_IOCTL, 0x95, s64[2]) +#define PPSETTIME64 _IOW(PP_IOCTL, 0x96, s64[2]) + +static inline void pp_enable_irq(struct pp_struct *pp) +{ + struct parport *port = pp->pdev->port; + + port->ops->enable_irq(port); +} + +static ssize_t pp_read(struct file *file, char __user *buf, size_t count, + loff_t *ppos) +{ + unsigned int minor = iminor(file_inode(file)); + struct pp_struct *pp = file->private_data; + char *kbuffer; + ssize_t bytes_read = 0; + struct parport *pport; + int mode; + + if (!(pp->flags & PP_CLAIMED)) { + /* Don't have the port claimed */ + pr_debug(CHRDEV "%x: claim the port first\n", minor); + return -EINVAL; + } + + /* Trivial case. */ + if (count == 0) + return 0; + + kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL); + if (!kbuffer) + return -ENOMEM; + pport = pp->pdev->port; + mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR); + + parport_set_timeout(pp->pdev, + (file->f_flags & O_NONBLOCK) ? + PARPORT_INACTIVITY_O_NONBLOCK : + pp->default_inactivity); + + while (bytes_read == 0) { + ssize_t need = min_t(unsigned long, count, PP_BUFFER_SIZE); + + if (mode == IEEE1284_MODE_EPP) { + /* various specials for EPP mode */ + int flags = 0; + size_t (*fn)(struct parport *, void *, size_t, int); + + if (pp->flags & PP_W91284PIC) + flags |= PARPORT_W91284PIC; + if (pp->flags & PP_FASTREAD) + flags |= PARPORT_EPP_FAST; + if (pport->ieee1284.mode & IEEE1284_ADDR) + fn = pport->ops->epp_read_addr; + else + fn = pport->ops->epp_read_data; + bytes_read = (*fn)(pport, kbuffer, need, flags); + } else { + bytes_read = parport_read(pport, kbuffer, need); + } + + if (bytes_read != 0) + break; + + if (file->f_flags & O_NONBLOCK) { + bytes_read = -EAGAIN; + break; + } + + if (signal_pending(current)) { + bytes_read = -ERESTARTSYS; + break; + } + + cond_resched(); + } + + parport_set_timeout(pp->pdev, pp->default_inactivity); + + if (bytes_read > 0 && copy_to_user(buf, kbuffer, bytes_read)) + bytes_read = -EFAULT; + + kfree(kbuffer); + pp_enable_irq(pp); + return bytes_read; +} + +static ssize_t pp_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + unsigned int minor = iminor(file_inode(file)); + struct pp_struct *pp = file->private_data; + char *kbuffer; + ssize_t bytes_written = 0; + ssize_t wrote; + int mode; + struct parport *pport; + + if (!(pp->flags & PP_CLAIMED)) { + /* Don't have the port claimed */ + pr_debug(CHRDEV "%x: claim the port first\n", minor); + return -EINVAL; + } + + kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL); + if (!kbuffer) + return -ENOMEM; + + pport = pp->pdev->port; + mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR); + + parport_set_timeout(pp->pdev, + (file->f_flags & O_NONBLOCK) ? + PARPORT_INACTIVITY_O_NONBLOCK : + pp->default_inactivity); + + while (bytes_written < count) { + ssize_t n = min_t(unsigned long, count - bytes_written, PP_BUFFER_SIZE); + + if (copy_from_user(kbuffer, buf + bytes_written, n)) { + bytes_written = -EFAULT; + break; + } + + if ((pp->flags & PP_FASTWRITE) && (mode == IEEE1284_MODE_EPP)) { + /* do a fast EPP write */ + if (pport->ieee1284.mode & IEEE1284_ADDR) { + wrote = pport->ops->epp_write_addr(pport, + kbuffer, n, PARPORT_EPP_FAST); + } else { + wrote = pport->ops->epp_write_data(pport, + kbuffer, n, PARPORT_EPP_FAST); + } + } else { + wrote = parport_write(pp->pdev->port, kbuffer, n); + } + + if (wrote <= 0) { + if (!bytes_written) + bytes_written = wrote; + break; + } + + bytes_written += wrote; + + if (file->f_flags & O_NONBLOCK) { + if (!bytes_written) + bytes_written = -EAGAIN; + break; + } + + if (signal_pending(current)) + break; + + cond_resched(); + } + + parport_set_timeout(pp->pdev, pp->default_inactivity); + + kfree(kbuffer); + pp_enable_irq(pp); + return bytes_written; +} + +static void pp_irq(void *private) +{ + struct pp_struct *pp = private; + + if (pp->irqresponse) { + parport_write_control(pp->pdev->port, pp->irqctl); + pp->irqresponse = 0; + } + + atomic_inc(&pp->irqc); + wake_up_interruptible(&pp->irq_wait); +} + +static int register_device(int minor, struct pp_struct *pp) +{ + struct parport *port; + struct pardevice *pdev = NULL; + char *name; + struct pardev_cb ppdev_cb; + int rc = 0, index; + + name = kasprintf(GFP_KERNEL, CHRDEV "%x", minor); + if (name == NULL) + return -ENOMEM; + + port = parport_find_number(minor); + if (!port) { + pr_warn("%s: no associated port!\n", name); + rc = -ENXIO; + goto err; + } + + index = ida_simple_get(&ida_index, 0, 0, GFP_KERNEL); + memset(&ppdev_cb, 0, sizeof(ppdev_cb)); + ppdev_cb.irq_func = pp_irq; + ppdev_cb.flags = (pp->flags & PP_EXCL) ? PARPORT_FLAG_EXCL : 0; + ppdev_cb.private = pp; + pdev = parport_register_dev_model(port, name, &ppdev_cb, index); + parport_put_port(port); + + if (!pdev) { + pr_warn("%s: failed to register device!\n", name); + rc = -ENXIO; + ida_simple_remove(&ida_index, index); + goto err; + } + + pp->pdev = pdev; + pp->index = index; + dev_dbg(&pdev->dev, "registered pardevice\n"); +err: + kfree(name); + return rc; +} + +static enum ieee1284_phase init_phase(int mode) +{ + switch (mode & ~(IEEE1284_DEVICEID + | IEEE1284_ADDR)) { + case IEEE1284_MODE_NIBBLE: + case IEEE1284_MODE_BYTE: + return IEEE1284_PH_REV_IDLE; + } + return IEEE1284_PH_FWD_IDLE; +} + +static int pp_set_timeout(struct pardevice *pdev, long tv_sec, int tv_usec) +{ + long to_jiffies; + + if ((tv_sec < 0) || (tv_usec < 0)) + return -EINVAL; + + to_jiffies = usecs_to_jiffies(tv_usec); + to_jiffies += tv_sec * HZ; + if (to_jiffies <= 0) + return -EINVAL; + + pdev->timeout = to_jiffies; + return 0; +} + +static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + unsigned int minor = iminor(file_inode(file)); + struct pp_struct *pp = file->private_data; + struct parport *port; + void __user *argp = (void __user *)arg; + struct ieee1284_info *info; + unsigned char reg; + unsigned char mask; + int mode; + s32 time32[2]; + s64 time64[2]; + struct timespec64 ts; + int ret; + + /* First handle the cases that don't take arguments. */ + switch (cmd) { + case PPCLAIM: + { + if (pp->flags & PP_CLAIMED) { + dev_dbg(&pp->pdev->dev, "you've already got it!\n"); + return -EINVAL; + } + + /* Deferred device registration. */ + if (!pp->pdev) { + int err = register_device(minor, pp); + + if (err) + return err; + } + + ret = parport_claim_or_block(pp->pdev); + if (ret < 0) + return ret; + + pp->flags |= PP_CLAIMED; + + /* For interrupt-reporting to work, we need to be + * informed of each interrupt. */ + pp_enable_irq(pp); + + /* We may need to fix up the state machine. */ + info = &pp->pdev->port->ieee1284; + pp->saved_state.mode = info->mode; + pp->saved_state.phase = info->phase; + info->mode = pp->state.mode; + info->phase = pp->state.phase; + pp->default_inactivity = parport_set_timeout(pp->pdev, 0); + parport_set_timeout(pp->pdev, pp->default_inactivity); + + return 0; + } + case PPEXCL: + if (pp->pdev) { + dev_dbg(&pp->pdev->dev, + "too late for PPEXCL; already registered\n"); + if (pp->flags & PP_EXCL) + /* But it's not really an error. */ + return 0; + /* There's no chance of making the driver happy. */ + return -EINVAL; + } + + /* Just remember to register the device exclusively + * when we finally do the registration. */ + pp->flags |= PP_EXCL; + return 0; + case PPSETMODE: + { + int mode; + + if (copy_from_user(&mode, argp, sizeof(mode))) + return -EFAULT; + /* FIXME: validate mode */ + pp->state.mode = mode; + pp->state.phase = init_phase(mode); + + if (pp->flags & PP_CLAIMED) { + pp->pdev->port->ieee1284.mode = mode; + pp->pdev->port->ieee1284.phase = pp->state.phase; + } + + return 0; + } + case PPGETMODE: + { + int mode; + + if (pp->flags & PP_CLAIMED) + mode = pp->pdev->port->ieee1284.mode; + else + mode = pp->state.mode; + + if (copy_to_user(argp, &mode, sizeof(mode))) + return -EFAULT; + return 0; + } + case PPSETPHASE: + { + int phase; + + if (copy_from_user(&phase, argp, sizeof(phase))) + return -EFAULT; + + /* FIXME: validate phase */ + pp->state.phase = phase; + + if (pp->flags & PP_CLAIMED) + pp->pdev->port->ieee1284.phase = phase; + + return 0; + } + case PPGETPHASE: + { + int phase; + + if (pp->flags & PP_CLAIMED) + phase = pp->pdev->port->ieee1284.phase; + else + phase = pp->state.phase; + if (copy_to_user(argp, &phase, sizeof(phase))) + return -EFAULT; + return 0; + } + case PPGETMODES: + { + unsigned int modes; + + port = parport_find_number(minor); + if (!port) + return -ENODEV; + + modes = port->modes; + parport_put_port(port); + if (copy_to_user(argp, &modes, sizeof(modes))) + return -EFAULT; + return 0; + } + case PPSETFLAGS: + { + int uflags; + + if (copy_from_user(&uflags, argp, sizeof(uflags))) + return -EFAULT; + pp->flags &= ~PP_FLAGMASK; + pp->flags |= (uflags & PP_FLAGMASK); + return 0; + } + case PPGETFLAGS: + { + int uflags; + + uflags = pp->flags & PP_FLAGMASK; + if (copy_to_user(argp, &uflags, sizeof(uflags))) + return -EFAULT; + return 0; + } + } /* end switch() */ + + /* Everything else requires the port to be claimed, so check + * that now. */ + if ((pp->flags & PP_CLAIMED) == 0) { + pr_debug(CHRDEV "%x: claim the port first\n", minor); + return -EINVAL; + } + + port = pp->pdev->port; + switch (cmd) { + case PPRSTATUS: + reg = parport_read_status(port); + if (copy_to_user(argp, ®, sizeof(reg))) + return -EFAULT; + return 0; + case PPRDATA: + reg = parport_read_data(port); + if (copy_to_user(argp, ®, sizeof(reg))) + return -EFAULT; + return 0; + case PPRCONTROL: + reg = parport_read_control(port); + if (copy_to_user(argp, ®, sizeof(reg))) + return -EFAULT; + return 0; + case PPYIELD: + parport_yield_blocking(pp->pdev); + return 0; + + case PPRELEASE: + /* Save the state machine's state. */ + info = &pp->pdev->port->ieee1284; + pp->state.mode = info->mode; + pp->state.phase = info->phase; + info->mode = pp->saved_state.mode; + info->phase = pp->saved_state.phase; + parport_release(pp->pdev); + pp->flags &= ~PP_CLAIMED; + return 0; + + case PPWCONTROL: + if (copy_from_user(®, argp, sizeof(reg))) + return -EFAULT; + parport_write_control(port, reg); + return 0; + + case PPWDATA: + if (copy_from_user(®, argp, sizeof(reg))) + return -EFAULT; + parport_write_data(port, reg); + return 0; + + case PPFCONTROL: + if (copy_from_user(&mask, argp, + sizeof(mask))) + return -EFAULT; + if (copy_from_user(®, 1 + (unsigned char __user *) arg, + sizeof(reg))) + return -EFAULT; + parport_frob_control(port, mask, reg); + return 0; + + case PPDATADIR: + if (copy_from_user(&mode, argp, sizeof(mode))) + return -EFAULT; + if (mode) + port->ops->data_reverse(port); + else + port->ops->data_forward(port); + return 0; + + case PPNEGOT: + if (copy_from_user(&mode, argp, sizeof(mode))) + return -EFAULT; + switch ((ret = parport_negotiate(port, mode))) { + case 0: break; + case -1: /* handshake failed, peripheral not IEEE 1284 */ + ret = -EIO; + break; + case 1: /* handshake succeeded, peripheral rejected mode */ + ret = -ENXIO; + break; + } + pp_enable_irq(pp); + return ret; + + case PPWCTLONIRQ: + if (copy_from_user(®, argp, sizeof(reg))) + return -EFAULT; + + /* Remember what to set the control lines to, for next + * time we get an interrupt. */ + pp->irqctl = reg; + pp->irqresponse = 1; + return 0; + + case PPCLRIRQ: + ret = atomic_read(&pp->irqc); + if (copy_to_user(argp, &ret, sizeof(ret))) + return -EFAULT; + atomic_sub(ret, &pp->irqc); + return 0; + + case PPSETTIME32: + if (copy_from_user(time32, argp, sizeof(time32))) + return -EFAULT; + + if ((time32[0] < 0) || (time32[1] < 0)) + return -EINVAL; + + return pp_set_timeout(pp->pdev, time32[0], time32[1]); + + case PPSETTIME64: + if (copy_from_user(time64, argp, sizeof(time64))) + return -EFAULT; + + if ((time64[0] < 0) || (time64[1] < 0)) + return -EINVAL; + + if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall()) + time64[1] >>= 32; + + return pp_set_timeout(pp->pdev, time64[0], time64[1]); + + case PPGETTIME32: + jiffies_to_timespec64(pp->pdev->timeout, &ts); + time32[0] = ts.tv_sec; + time32[1] = ts.tv_nsec / NSEC_PER_USEC; + + if (copy_to_user(argp, time32, sizeof(time32))) + return -EFAULT; + + return 0; + + case PPGETTIME64: + jiffies_to_timespec64(pp->pdev->timeout, &ts); + time64[0] = ts.tv_sec; + time64[1] = ts.tv_nsec / NSEC_PER_USEC; + + if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall()) + time64[1] <<= 32; + + if (copy_to_user(argp, time64, sizeof(time64))) + return -EFAULT; + + return 0; + + default: + dev_dbg(&pp->pdev->dev, "What? (cmd=0x%x)\n", cmd); + return -EINVAL; + } + + /* Keep the compiler happy */ + return 0; +} + +static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + long ret; + + mutex_lock(&pp_do_mutex); + ret = pp_do_ioctl(file, cmd, arg); + mutex_unlock(&pp_do_mutex); + return ret; +} + +static int pp_open(struct inode *inode, struct file *file) +{ + unsigned int minor = iminor(inode); + struct pp_struct *pp; + + if (minor >= PARPORT_MAX) + return -ENXIO; + + pp = kmalloc(sizeof(struct pp_struct), GFP_KERNEL); + if (!pp) + return -ENOMEM; + + pp->state.mode = IEEE1284_MODE_COMPAT; + pp->state.phase = init_phase(pp->state.mode); + pp->flags = 0; + pp->irqresponse = 0; + atomic_set(&pp->irqc, 0); + init_waitqueue_head(&pp->irq_wait); + + /* Defer the actual device registration until the first claim. + * That way, we know whether or not the driver wants to have + * exclusive access to the port (PPEXCL). + */ + pp->pdev = NULL; + file->private_data = pp; + + return 0; +} + +static int pp_release(struct inode *inode, struct file *file) +{ + unsigned int minor = iminor(inode); + struct pp_struct *pp = file->private_data; + int compat_negot; + + compat_negot = 0; + if (!(pp->flags & PP_CLAIMED) && pp->pdev && + (pp->state.mode != IEEE1284_MODE_COMPAT)) { + struct ieee1284_info *info; + + /* parport released, but not in compatibility mode */ + parport_claim_or_block(pp->pdev); + pp->flags |= PP_CLAIMED; + info = &pp->pdev->port->ieee1284; + pp->saved_state.mode = info->mode; + pp->saved_state.phase = info->phase; + info->mode = pp->state.mode; + info->phase = pp->state.phase; + compat_negot = 1; + } else if ((pp->flags & PP_CLAIMED) && pp->pdev && + (pp->pdev->port->ieee1284.mode != IEEE1284_MODE_COMPAT)) { + compat_negot = 2; + } + if (compat_negot) { + parport_negotiate(pp->pdev->port, IEEE1284_MODE_COMPAT); + dev_dbg(&pp->pdev->dev, + "negotiated back to compatibility mode because user-space forgot\n"); + } + + if ((pp->flags & PP_CLAIMED) && pp->pdev) { + struct ieee1284_info *info; + + info = &pp->pdev->port->ieee1284; + pp->state.mode = info->mode; + pp->state.phase = info->phase; + info->mode = pp->saved_state.mode; + info->phase = pp->saved_state.phase; + parport_release(pp->pdev); + if (compat_negot != 1) { + pr_debug(CHRDEV "%x: released pardevice " + "because user-space forgot\n", minor); + } + } + + if (pp->pdev) { + parport_unregister_device(pp->pdev); + ida_simple_remove(&ida_index, pp->index); + pp->pdev = NULL; + pr_debug(CHRDEV "%x: unregistered pardevice\n", minor); + } + + kfree(pp); + + return 0; +} + +/* No kernel lock held - fine */ +static __poll_t pp_poll(struct file *file, poll_table *wait) +{ + struct pp_struct *pp = file->private_data; + __poll_t mask = 0; + + poll_wait(file, &pp->irq_wait, wait); + if (atomic_read(&pp->irqc)) + mask |= EPOLLIN | EPOLLRDNORM; + + return mask; +} + +static struct class *ppdev_class; + +static const struct file_operations pp_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .read = pp_read, + .write = pp_write, + .poll = pp_poll, + .unlocked_ioctl = pp_ioctl, + .compat_ioctl = compat_ptr_ioctl, + .open = pp_open, + .release = pp_release, +}; + +static void pp_attach(struct parport *port) +{ + struct device *ret; + + if (devices[port->number]) + return; + + ret = device_create(ppdev_class, port->dev, + MKDEV(PP_MAJOR, port->number), NULL, + "parport%d", port->number); + if (IS_ERR(ret)) { + pr_err("Failed to create device parport%d\n", + port->number); + return; + } + devices[port->number] = ret; +} + +static void pp_detach(struct parport *port) +{ + if (!devices[port->number]) + return; + + device_destroy(ppdev_class, MKDEV(PP_MAJOR, port->number)); + devices[port->number] = NULL; +} + +static int pp_probe(struct pardevice *par_dev) +{ + struct device_driver *drv = par_dev->dev.driver; + int len = strlen(drv->name); + + if (strncmp(par_dev->name, drv->name, len)) + return -ENODEV; + + return 0; +} + +static struct parport_driver pp_driver = { + .name = CHRDEV, + .probe = pp_probe, + .match_port = pp_attach, + .detach = pp_detach, + .devmodel = true, +}; + +static int __init ppdev_init(void) +{ + int err = 0; + + if (register_chrdev(PP_MAJOR, CHRDEV, &pp_fops)) { + pr_warn(CHRDEV ": unable to get major %d\n", PP_MAJOR); + return -EIO; + } + ppdev_class = class_create(THIS_MODULE, CHRDEV); + if (IS_ERR(ppdev_class)) { + err = PTR_ERR(ppdev_class); + goto out_chrdev; + } + err = parport_register_driver(&pp_driver); + if (err < 0) { + pr_warn(CHRDEV ": unable to register with parport\n"); + goto out_class; + } + + pr_info(PP_VERSION "\n"); + goto out; + +out_class: + class_destroy(ppdev_class); +out_chrdev: + unregister_chrdev(PP_MAJOR, CHRDEV); +out: + return err; +} + +static void __exit ppdev_cleanup(void) +{ + /* Clean up all parport stuff */ + parport_unregister_driver(&pp_driver); + class_destroy(ppdev_class); + unregister_chrdev(PP_MAJOR, CHRDEV); +} + +module_init(ppdev_init); +module_exit(ppdev_cleanup); + +MODULE_LICENSE("GPL"); +MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR); |