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-rw-r--r--drivers/char/ppdev.c878
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, &reg, sizeof(reg)))
+ return -EFAULT;
+ return 0;
+ case PPRDATA:
+ reg = parport_read_data(port);
+ if (copy_to_user(argp, &reg, sizeof(reg)))
+ return -EFAULT;
+ return 0;
+ case PPRCONTROL:
+ reg = parport_read_control(port);
+ if (copy_to_user(argp, &reg, 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(&reg, argp, sizeof(reg)))
+ return -EFAULT;
+ parport_write_control(port, reg);
+ return 0;
+
+ case PPWDATA:
+ if (copy_from_user(&reg, 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(&reg, 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(&reg, 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);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-02 15:51:16 +0000