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878 lines
20 KiB
878 lines
20 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
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/* |
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* linux/drivers/char/ppdev.c |
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* |
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* This is the code behind /dev/parport* -- it allows a user-space |
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* application to use the parport subsystem. |
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* |
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* Copyright (C) 1998-2000, 2002 Tim Waugh <[email protected]> |
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* |
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* A /dev/parportx device node represents an arbitrary device |
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* on port 'x'. The following operations are possible: |
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* |
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* open do nothing, set up default IEEE 1284 protocol to be COMPAT |
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* close release port and unregister device (if necessary) |
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* ioctl |
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* EXCL register device exclusively (may fail) |
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* CLAIM (register device first time) parport_claim_or_block |
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* RELEASE parport_release |
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* SETMODE set the IEEE 1284 protocol to use for read/write |
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* SETPHASE set the IEEE 1284 phase of a particular mode. Not to be |
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* confused with ioctl(fd, SETPHASER, &stun). ;-) |
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* DATADIR data_forward / data_reverse |
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* WDATA write_data |
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* RDATA read_data |
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* WCONTROL write_control |
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* RCONTROL read_control |
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* FCONTROL frob_control |
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* RSTATUS read_status |
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* NEGOT parport_negotiate |
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* YIELD parport_yield_blocking |
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* WCTLONIRQ on interrupt, set control lines |
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* CLRIRQ clear (and return) interrupt count |
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* SETTIME sets device timeout (struct timeval) |
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* GETTIME gets device timeout (struct timeval) |
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* GETMODES gets hardware supported modes (unsigned int) |
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* GETMODE gets the current IEEE1284 mode |
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* GETPHASE gets the current IEEE1284 phase |
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* GETFLAGS gets current (user-visible) flags |
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* SETFLAGS sets current (user-visible) flags |
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* read/write read or write in current IEEE 1284 protocol |
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* select wait for interrupt (in readfds) |
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* |
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* Changes: |
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* Added SETTIME/GETTIME ioctl, Fred Barnes, 1999. |
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* |
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* Arnaldo Carvalho de Melo <[email protected]> 2000/08/25 |
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* - On error, copy_from_user and copy_to_user do not return -EFAULT, |
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* They return the positive number of bytes *not* copied due to address |
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* space errors. |
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* |
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* Added GETMODES/GETMODE/GETPHASE ioctls, Fred Barnes <[email protected]>, 03/01/2001. |
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* Added GETFLAGS/SETFLAGS ioctls, Fred Barnes, 04/2001 |
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*/ |
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|
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#include <linux/module.h> |
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#include <linux/init.h> |
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#include <linux/sched/signal.h> |
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#include <linux/device.h> |
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#include <linux/ioctl.h> |
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#include <linux/parport.h> |
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#include <linux/ctype.h> |
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#include <linux/poll.h> |
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#include <linux/slab.h> |
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#include <linux/major.h> |
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#include <linux/ppdev.h> |
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#include <linux/mutex.h> |
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#include <linux/uaccess.h> |
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#include <linux/compat.h> |
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|
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#define PP_VERSION "ppdev: user-space parallel port driver" |
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#define CHRDEV "ppdev" |
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struct pp_struct { |
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struct pardevice *pdev; |
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wait_queue_head_t irq_wait; |
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atomic_t irqc; |
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unsigned int flags; |
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int irqresponse; |
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unsigned char irqctl; |
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struct ieee1284_info state; |
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struct ieee1284_info saved_state; |
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long default_inactivity; |
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int index; |
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}; |
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|
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/* should we use PARDEVICE_MAX here? */ |
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static struct device *devices[PARPORT_MAX]; |
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|
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static DEFINE_IDA(ida_index); |
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|
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/* pp_struct.flags bitfields */ |
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#define PP_CLAIMED (1<<0) |
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#define PP_EXCL (1<<1) |
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|
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/* Other constants */ |
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#define PP_INTERRUPT_TIMEOUT (10 * HZ) /* 10s */ |
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#define PP_BUFFER_SIZE 1024 |
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#define PARDEVICE_MAX 8 |
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|
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static DEFINE_MUTEX(pp_do_mutex); |
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|
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/* define fixed sized ioctl cmd for y2038 migration */ |
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#define PPGETTIME32 _IOR(PP_IOCTL, 0x95, s32[2]) |
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#define PPSETTIME32 _IOW(PP_IOCTL, 0x96, s32[2]) |
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#define PPGETTIME64 _IOR(PP_IOCTL, 0x95, s64[2]) |
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#define PPSETTIME64 _IOW(PP_IOCTL, 0x96, s64[2]) |
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|
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static inline void pp_enable_irq(struct pp_struct *pp) |
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{ |
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struct parport *port = pp->pdev->port; |
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|
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port->ops->enable_irq(port); |
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} |
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|
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static ssize_t pp_read(struct file *file, char __user *buf, size_t count, |
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loff_t *ppos) |
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{ |
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unsigned int minor = iminor(file_inode(file)); |
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struct pp_struct *pp = file->private_data; |
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char *kbuffer; |
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ssize_t bytes_read = 0; |
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struct parport *pport; |
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int mode; |
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|
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if (!(pp->flags & PP_CLAIMED)) { |
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/* Don't have the port claimed */ |
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pr_debug(CHRDEV "%x: claim the port first\n", minor); |
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return -EINVAL; |
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} |
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|
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/* Trivial case. */ |
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if (count == 0) |
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return 0; |
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kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL); |
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if (!kbuffer) |
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return -ENOMEM; |
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pport = pp->pdev->port; |
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mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR); |
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parport_set_timeout(pp->pdev, |
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(file->f_flags & O_NONBLOCK) ? |
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PARPORT_INACTIVITY_O_NONBLOCK : |
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pp->default_inactivity); |
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|
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while (bytes_read == 0) { |
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ssize_t need = min_t(unsigned long, count, PP_BUFFER_SIZE); |
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|
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if (mode == IEEE1284_MODE_EPP) { |
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/* various specials for EPP mode */ |
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int flags = 0; |
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size_t (*fn)(struct parport *, void *, size_t, int); |
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|
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if (pp->flags & PP_W91284PIC) |
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flags |= PARPORT_W91284PIC; |
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if (pp->flags & PP_FASTREAD) |
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flags |= PARPORT_EPP_FAST; |
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if (pport->ieee1284.mode & IEEE1284_ADDR) |
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fn = pport->ops->epp_read_addr; |
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else |
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fn = pport->ops->epp_read_data; |
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bytes_read = (*fn)(pport, kbuffer, need, flags); |
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} else { |
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bytes_read = parport_read(pport, kbuffer, need); |
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} |
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if (bytes_read != 0) |
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break; |
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if (file->f_flags & O_NONBLOCK) { |
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bytes_read = -EAGAIN; |
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break; |
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} |
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if (signal_pending(current)) { |
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bytes_read = -ERESTARTSYS; |
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break; |
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} |
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cond_resched(); |
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} |
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parport_set_timeout(pp->pdev, pp->default_inactivity); |
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if (bytes_read > 0 && copy_to_user(buf, kbuffer, bytes_read)) |
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bytes_read = -EFAULT; |
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kfree(kbuffer); |
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pp_enable_irq(pp); |
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return bytes_read; |
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} |
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static ssize_t pp_write(struct file *file, const char __user *buf, |
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size_t count, loff_t *ppos) |
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{ |
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unsigned int minor = iminor(file_inode(file)); |
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struct pp_struct *pp = file->private_data; |
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char *kbuffer; |
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ssize_t bytes_written = 0; |
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ssize_t wrote; |
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int mode; |
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struct parport *pport; |
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if (!(pp->flags & PP_CLAIMED)) { |
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/* Don't have the port claimed */ |
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pr_debug(CHRDEV "%x: claim the port first\n", minor); |
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return -EINVAL; |
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} |
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kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL); |
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if (!kbuffer) |
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return -ENOMEM; |
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pport = pp->pdev->port; |
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mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR); |
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parport_set_timeout(pp->pdev, |
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(file->f_flags & O_NONBLOCK) ? |
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PARPORT_INACTIVITY_O_NONBLOCK : |
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pp->default_inactivity); |
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while (bytes_written < count) { |
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ssize_t n = min_t(unsigned long, count - bytes_written, PP_BUFFER_SIZE); |
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if (copy_from_user(kbuffer, buf + bytes_written, n)) { |
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bytes_written = -EFAULT; |
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break; |
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} |
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if ((pp->flags & PP_FASTWRITE) && (mode == IEEE1284_MODE_EPP)) { |
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/* do a fast EPP write */ |
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if (pport->ieee1284.mode & IEEE1284_ADDR) { |
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wrote = pport->ops->epp_write_addr(pport, |
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kbuffer, n, PARPORT_EPP_FAST); |
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} else { |
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wrote = pport->ops->epp_write_data(pport, |
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kbuffer, n, PARPORT_EPP_FAST); |
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} |
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} else { |
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wrote = parport_write(pp->pdev->port, kbuffer, n); |
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} |
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if (wrote <= 0) { |
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if (!bytes_written) |
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bytes_written = wrote; |
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break; |
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} |
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bytes_written += wrote; |
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if (file->f_flags & O_NONBLOCK) { |
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if (!bytes_written) |
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bytes_written = -EAGAIN; |
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break; |
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} |
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if (signal_pending(current)) |
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break; |
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cond_resched(); |
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} |
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parport_set_timeout(pp->pdev, pp->default_inactivity); |
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kfree(kbuffer); |
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pp_enable_irq(pp); |
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return bytes_written; |
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} |
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static void pp_irq(void *private) |
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{ |
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struct pp_struct *pp = private; |
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if (pp->irqresponse) { |
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parport_write_control(pp->pdev->port, pp->irqctl); |
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pp->irqresponse = 0; |
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} |
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atomic_inc(&pp->irqc); |
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wake_up_interruptible(&pp->irq_wait); |
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} |
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static int register_device(int minor, struct pp_struct *pp) |
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{ |
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struct parport *port; |
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struct pardevice *pdev = NULL; |
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char *name; |
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struct pardev_cb ppdev_cb; |
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int rc = 0, index; |
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name = kasprintf(GFP_KERNEL, CHRDEV "%x", minor); |
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if (name == NULL) |
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return -ENOMEM; |
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port = parport_find_number(minor); |
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if (!port) { |
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pr_warn("%s: no associated port!\n", name); |
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rc = -ENXIO; |
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goto err; |
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} |
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index = ida_simple_get(&ida_index, 0, 0, GFP_KERNEL); |
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memset(&ppdev_cb, 0, sizeof(ppdev_cb)); |
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ppdev_cb.irq_func = pp_irq; |
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ppdev_cb.flags = (pp->flags & PP_EXCL) ? PARPORT_FLAG_EXCL : 0; |
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ppdev_cb.private = pp; |
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pdev = parport_register_dev_model(port, name, &ppdev_cb, index); |
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parport_put_port(port); |
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if (!pdev) { |
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pr_warn("%s: failed to register device!\n", name); |
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rc = -ENXIO; |
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ida_simple_remove(&ida_index, index); |
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goto err; |
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} |
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pp->pdev = pdev; |
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pp->index = index; |
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dev_dbg(&pdev->dev, "registered pardevice\n"); |
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err: |
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kfree(name); |
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return rc; |
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} |
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static enum ieee1284_phase init_phase(int mode) |
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{ |
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switch (mode & ~(IEEE1284_DEVICEID |
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| IEEE1284_ADDR)) { |
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case IEEE1284_MODE_NIBBLE: |
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case IEEE1284_MODE_BYTE: |
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return IEEE1284_PH_REV_IDLE; |
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} |
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return IEEE1284_PH_FWD_IDLE; |
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} |
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static int pp_set_timeout(struct pardevice *pdev, long tv_sec, int tv_usec) |
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{ |
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long to_jiffies; |
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if ((tv_sec < 0) || (tv_usec < 0)) |
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return -EINVAL; |
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to_jiffies = usecs_to_jiffies(tv_usec); |
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to_jiffies += tv_sec * HZ; |
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if (to_jiffies <= 0) |
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return -EINVAL; |
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pdev->timeout = to_jiffies; |
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return 0; |
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} |
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static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
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{ |
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unsigned int minor = iminor(file_inode(file)); |
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struct pp_struct *pp = file->private_data; |
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struct parport *port; |
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void __user *argp = (void __user *)arg; |
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struct ieee1284_info *info; |
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unsigned char reg; |
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unsigned char mask; |
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int mode; |
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s32 time32[2]; |
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s64 time64[2]; |
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struct timespec64 ts; |
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int ret; |
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/* First handle the cases that don't take arguments. */ |
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switch (cmd) { |
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case PPCLAIM: |
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{ |
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if (pp->flags & PP_CLAIMED) { |
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dev_dbg(&pp->pdev->dev, "you've already got it!\n"); |
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return -EINVAL; |
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} |
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/* Deferred device registration. */ |
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if (!pp->pdev) { |
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int err = register_device(minor, pp); |
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if (err) |
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return err; |
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} |
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ret = parport_claim_or_block(pp->pdev); |
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if (ret < 0) |
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return ret; |
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pp->flags |= PP_CLAIMED; |
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|
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/* For interrupt-reporting to work, we need to be |
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* informed of each interrupt. */ |
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pp_enable_irq(pp); |
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/* We may need to fix up the state machine. */ |
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info = &pp->pdev->port->ieee1284; |
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pp->saved_state.mode = info->mode; |
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pp->saved_state.phase = info->phase; |
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info->mode = pp->state.mode; |
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info->phase = pp->state.phase; |
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pp->default_inactivity = parport_set_timeout(pp->pdev, 0); |
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parport_set_timeout(pp->pdev, pp->default_inactivity); |
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return 0; |
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} |
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case PPEXCL: |
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if (pp->pdev) { |
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dev_dbg(&pp->pdev->dev, |
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"too late for PPEXCL; already registered\n"); |
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if (pp->flags & PP_EXCL) |
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/* But it's not really an error. */ |
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return 0; |
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/* There's no chance of making the driver happy. */ |
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return -EINVAL; |
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} |
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|
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/* Just remember to register the device exclusively |
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* when we finally do the registration. */ |
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pp->flags |= PP_EXCL; |
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return 0; |
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case PPSETMODE: |
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{ |
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int mode; |
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|
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if (copy_from_user(&mode, argp, sizeof(mode))) |
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return -EFAULT; |
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/* FIXME: validate mode */ |
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pp->state.mode = mode; |
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pp->state.phase = init_phase(mode); |
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|
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if (pp->flags & PP_CLAIMED) { |
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pp->pdev->port->ieee1284.mode = mode; |
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pp->pdev->port->ieee1284.phase = pp->state.phase; |
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} |
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return 0; |
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} |
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case PPGETMODE: |
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{ |
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int mode; |
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if (pp->flags & PP_CLAIMED) |
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mode = pp->pdev->port->ieee1284.mode; |
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else |
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mode = pp->state.mode; |
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|
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if (copy_to_user(argp, &mode, sizeof(mode))) |
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return -EFAULT; |
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return 0; |
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} |
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case PPSETPHASE: |
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{ |
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int phase; |
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|
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if (copy_from_user(&phase, argp, sizeof(phase))) |
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return -EFAULT; |
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|
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/* FIXME: validate phase */ |
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pp->state.phase = phase; |
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|
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if (pp->flags & PP_CLAIMED) |
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pp->pdev->port->ieee1284.phase = phase; |
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return 0; |
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} |
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case PPGETPHASE: |
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{ |
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int phase; |
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|
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if (pp->flags & PP_CLAIMED) |
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phase = pp->pdev->port->ieee1284.phase; |
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else |
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phase = pp->state.phase; |
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if (copy_to_user(argp, &phase, sizeof(phase))) |
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return -EFAULT; |
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return 0; |
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} |
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case PPGETMODES: |
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{ |
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unsigned int modes; |
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port = parport_find_number(minor); |
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if (!port) |
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return -ENODEV; |
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|
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modes = port->modes; |
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parport_put_port(port); |
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if (copy_to_user(argp, &modes, sizeof(modes))) |
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return -EFAULT; |
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return 0; |
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} |
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case PPSETFLAGS: |
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{ |
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int uflags; |
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|
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if (copy_from_user(&uflags, argp, sizeof(uflags))) |
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return -EFAULT; |
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pp->flags &= ~PP_FLAGMASK; |
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pp->flags |= (uflags & PP_FLAGMASK); |
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return 0; |
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} |
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case PPGETFLAGS: |
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{ |
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int uflags; |
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|
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uflags = pp->flags & PP_FLAGMASK; |
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if (copy_to_user(argp, &uflags, sizeof(uflags))) |
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return -EFAULT; |
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return 0; |
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} |
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} /* end switch() */ |
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|
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/* Everything else requires the port to be claimed, so check |
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* that now. */ |
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if ((pp->flags & PP_CLAIMED) == 0) { |
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pr_debug(CHRDEV "%x: claim the port first\n", minor); |
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return -EINVAL; |
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} |
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|
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port = pp->pdev->port; |
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switch (cmd) { |
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case PPRSTATUS: |
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reg = parport_read_status(port); |
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if (copy_to_user(argp, ®, sizeof(reg))) |
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return -EFAULT; |
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return 0; |
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case PPRDATA: |
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reg = parport_read_data(port); |
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if (copy_to_user(argp, ®, sizeof(reg))) |
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return -EFAULT; |
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return 0; |
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case PPRCONTROL: |
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reg = parport_read_control(port); |
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if (copy_to_user(argp, ®, sizeof(reg))) |
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return -EFAULT; |
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return 0; |
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case PPYIELD: |
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parport_yield_blocking(pp->pdev); |
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return 0; |
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|
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case PPRELEASE: |
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/* Save the state machine's state. */ |
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info = &pp->pdev->port->ieee1284; |
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pp->state.mode = info->mode; |
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pp->state.phase = info->phase; |
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info->mode = pp->saved_state.mode; |
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info->phase = pp->saved_state.phase; |
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parport_release(pp->pdev); |
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pp->flags &= ~PP_CLAIMED; |
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return 0; |
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|
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case PPWCONTROL: |
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if (copy_from_user(®, argp, sizeof(reg))) |
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return -EFAULT; |
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parport_write_control(port, reg); |
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return 0; |
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|
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case PPWDATA: |
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if (copy_from_user(®, argp, sizeof(reg))) |
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return -EFAULT; |
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parport_write_data(port, reg); |
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return 0; |
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|
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case PPFCONTROL: |
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if (copy_from_user(&mask, argp, |
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sizeof(mask))) |
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return -EFAULT; |
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if (copy_from_user(®, 1 + (unsigned char __user *) arg, |
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sizeof(reg))) |
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return -EFAULT; |
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parport_frob_control(port, mask, reg); |
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return 0; |
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|
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case PPDATADIR: |
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if (copy_from_user(&mode, argp, sizeof(mode))) |
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return -EFAULT; |
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if (mode) |
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port->ops->data_reverse(port); |
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else |
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port->ops->data_forward(port); |
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return 0; |
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|
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case PPNEGOT: |
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if (copy_from_user(&mode, argp, sizeof(mode))) |
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return -EFAULT; |
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switch ((ret = parport_negotiate(port, mode))) { |
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case 0: break; |
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case -1: /* handshake failed, peripheral not IEEE 1284 */ |
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ret = -EIO; |
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break; |
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case 1: /* handshake succeeded, peripheral rejected mode */ |
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ret = -ENXIO; |
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break; |
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} |
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pp_enable_irq(pp); |
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return ret; |
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|
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case PPWCTLONIRQ: |
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if (copy_from_user(®, argp, sizeof(reg))) |
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return -EFAULT; |
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|
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/* Remember what to set the control lines to, for next |
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* 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);
|
|
|