2 * linux/drivers/char/ppdev.c
4 * This is the code behind /dev/parport* -- it allows a user-space
5 * application to use the parport subsystem.
7 * Copyright (C) 1998-2000, 2002 Tim Waugh <tim@cyberelk.net>
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
14 * A /dev/parportx device node represents an arbitrary device
15 * on port 'x'. The following operations are possible:
17 * open do nothing, set up default IEEE 1284 protocol to be COMPAT
18 * close release port and unregister device (if necessary)
20 * EXCL register device exclusively (may fail)
21 * CLAIM (register device first time) parport_claim_or_block
22 * RELEASE parport_release
23 * SETMODE set the IEEE 1284 protocol to use for read/write
24 * SETPHASE set the IEEE 1284 phase of a particular mode. Not to be
25 * confused with ioctl(fd, SETPHASER, &stun). ;-)
26 * DATADIR data_forward / data_reverse
29 * WCONTROL write_control
30 * RCONTROL read_control
31 * FCONTROL frob_control
33 * NEGOT parport_negotiate
34 * YIELD parport_yield_blocking
35 * WCTLONIRQ on interrupt, set control lines
36 * CLRIRQ clear (and return) interrupt count
37 * SETTIME sets device timeout (struct timeval)
38 * GETTIME gets device timeout (struct timeval)
39 * GETMODES gets hardware supported modes (unsigned int)
40 * GETMODE gets the current IEEE1284 mode
41 * GETPHASE gets the current IEEE1284 phase
42 * GETFLAGS gets current (user-visible) flags
43 * SETFLAGS sets current (user-visible) flags
44 * read/write read or write in current IEEE 1284 protocol
45 * select wait for interrupt (in readfds)
48 * Added SETTIME/GETTIME ioctl, Fred Barnes, 1999.
50 * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 2000/08/25
51 * - On error, copy_from_user and copy_to_user do not return -EFAULT,
52 * They return the positive number of bytes *not* copied due to address
55 * Added GETMODES/GETMODE/GETPHASE ioctls, Fred Barnes <frmb2@ukc.ac.uk>, 03/01/2001.
56 * Added GETFLAGS/SETFLAGS ioctls, Fred Barnes, 04/2001
59 #include <linux/module.h>
60 #include <linux/init.h>
61 #include <linux/sched.h>
62 #include <linux/device.h>
63 #include <linux/devfs_fs_kernel.h>
64 #include <linux/ioctl.h>
65 #include <linux/parport.h>
66 #include <linux/ctype.h>
67 #include <linux/poll.h>
68 #include <asm/uaccess.h>
69 #include <linux/ppdev.h>
70 #include <linux/smp_lock.h>
71 #include <linux/device.h>
73 #define PP_VERSION "ppdev: user-space parallel port driver"
74 #define CHRDEV "ppdev"
77 struct pardevice
* pdev
;
78 wait_queue_head_t irq_wait
;
83 struct ieee1284_info state
;
84 struct ieee1284_info saved_state
;
85 long default_inactivity
;
88 /* pp_struct.flags bitfields */
89 #define PP_CLAIMED (1<<0)
90 #define PP_EXCL (1<<1)
93 #define PP_INTERRUPT_TIMEOUT (10 * HZ) /* 10s */
94 #define PP_BUFFER_SIZE 1024
95 #define PARDEVICE_MAX 8
97 /* ROUND_UP macro from fs/select.c */
98 #define ROUND_UP(x,y) (((x)+(y)-1)/(y))
100 static inline void pp_enable_irq (struct pp_struct
*pp
)
102 struct parport
*port
= pp
->pdev
->port
;
103 port
->ops
->enable_irq (port
);
106 static ssize_t
pp_read (struct file
* file
, char __user
* buf
, size_t count
,
109 unsigned int minor
= iminor(file
->f_dentry
->d_inode
);
110 struct pp_struct
*pp
= file
->private_data
;
112 ssize_t bytes_read
= 0;
113 struct parport
*pport
;
116 if (!(pp
->flags
& PP_CLAIMED
)) {
117 /* Don't have the port claimed */
118 printk (KERN_DEBUG CHRDEV
"%x: claim the port first\n",
127 kbuffer
= kmalloc(min_t(size_t, count
, PP_BUFFER_SIZE
), GFP_KERNEL
);
131 pport
= pp
->pdev
->port
;
132 mode
= pport
->ieee1284
.mode
& ~(IEEE1284_DEVICEID
| IEEE1284_ADDR
);
134 parport_set_timeout (pp
->pdev
,
135 (file
->f_flags
& O_NONBLOCK
) ?
136 PARPORT_INACTIVITY_O_NONBLOCK
:
137 pp
->default_inactivity
);
139 while (bytes_read
== 0) {
140 ssize_t need
= min_t(unsigned long, count
, PP_BUFFER_SIZE
);
142 if (mode
== IEEE1284_MODE_EPP
) {
143 /* various specials for EPP mode */
145 size_t (*fn
)(struct parport
*, void *, size_t, int);
147 if (pp
->flags
& PP_W91284PIC
) {
148 flags
|= PARPORT_W91284PIC
;
150 if (pp
->flags
& PP_FASTREAD
) {
151 flags
|= PARPORT_EPP_FAST
;
153 if (pport
->ieee1284
.mode
& IEEE1284_ADDR
) {
154 fn
= pport
->ops
->epp_read_addr
;
156 fn
= pport
->ops
->epp_read_data
;
158 bytes_read
= (*fn
)(pport
, kbuffer
, need
, flags
);
160 bytes_read
= parport_read (pport
, kbuffer
, need
);
166 if (file
->f_flags
& O_NONBLOCK
) {
167 bytes_read
= -EAGAIN
;
171 if (signal_pending (current
)) {
172 bytes_read
= -ERESTARTSYS
;
179 parport_set_timeout (pp
->pdev
, pp
->default_inactivity
);
181 if (bytes_read
> 0 && copy_to_user (buf
, kbuffer
, bytes_read
))
182 bytes_read
= -EFAULT
;
189 static ssize_t
pp_write (struct file
* file
, const char __user
* buf
,
190 size_t count
, loff_t
* ppos
)
192 unsigned int minor
= iminor(file
->f_dentry
->d_inode
);
193 struct pp_struct
*pp
= file
->private_data
;
195 ssize_t bytes_written
= 0;
198 struct parport
*pport
;
200 if (!(pp
->flags
& PP_CLAIMED
)) {
201 /* Don't have the port claimed */
202 printk (KERN_DEBUG CHRDEV
"%x: claim the port first\n",
207 kbuffer
= kmalloc(min_t(size_t, count
, PP_BUFFER_SIZE
), GFP_KERNEL
);
211 pport
= pp
->pdev
->port
;
212 mode
= pport
->ieee1284
.mode
& ~(IEEE1284_DEVICEID
| IEEE1284_ADDR
);
214 parport_set_timeout (pp
->pdev
,
215 (file
->f_flags
& O_NONBLOCK
) ?
216 PARPORT_INACTIVITY_O_NONBLOCK
:
217 pp
->default_inactivity
);
219 while (bytes_written
< count
) {
220 ssize_t n
= min_t(unsigned long, count
- bytes_written
, PP_BUFFER_SIZE
);
222 if (copy_from_user (kbuffer
, buf
+ bytes_written
, n
)) {
223 bytes_written
= -EFAULT
;
227 if ((pp
->flags
& PP_FASTWRITE
) && (mode
== IEEE1284_MODE_EPP
)) {
228 /* do a fast EPP write */
229 if (pport
->ieee1284
.mode
& IEEE1284_ADDR
) {
230 wrote
= pport
->ops
->epp_write_addr (pport
,
231 kbuffer
, n
, PARPORT_EPP_FAST
);
233 wrote
= pport
->ops
->epp_write_data (pport
,
234 kbuffer
, n
, PARPORT_EPP_FAST
);
237 wrote
= parport_write (pp
->pdev
->port
, kbuffer
, n
);
241 if (!bytes_written
) {
242 bytes_written
= wrote
;
247 bytes_written
+= wrote
;
249 if (file
->f_flags
& O_NONBLOCK
) {
251 bytes_written
= -EAGAIN
;
255 if (signal_pending (current
)) {
256 if (!bytes_written
) {
257 bytes_written
= -EINTR
;
265 parport_set_timeout (pp
->pdev
, pp
->default_inactivity
);
269 return bytes_written
;
272 static void pp_irq (int irq
, void * private, struct pt_regs
* unused
)
274 struct pp_struct
* pp
= (struct pp_struct
*) private;
276 if (pp
->irqresponse
) {
277 parport_write_control (pp
->pdev
->port
, pp
->irqctl
);
281 atomic_inc (&pp
->irqc
);
282 wake_up_interruptible (&pp
->irq_wait
);
285 static int register_device (int minor
, struct pp_struct
*pp
)
287 struct parport
*port
;
288 struct pardevice
* pdev
= NULL
;
292 name
= kmalloc (strlen (CHRDEV
) + 3, GFP_KERNEL
);
296 sprintf (name
, CHRDEV
"%x", minor
);
298 port
= parport_find_number (minor
);
300 printk (KERN_WARNING
"%s: no associated port!\n", name
);
305 fl
= (pp
->flags
& PP_EXCL
) ? PARPORT_FLAG_EXCL
: 0;
306 pdev
= parport_register_device (port
, name
, NULL
,
307 NULL
, pp_irq
, fl
, pp
);
308 parport_put_port (port
);
311 printk (KERN_WARNING
"%s: failed to register device!\n", name
);
317 printk (KERN_DEBUG
"%s: registered pardevice\n", name
);
321 static enum ieee1284_phase
init_phase (int mode
)
323 switch (mode
& ~(IEEE1284_DEVICEID
325 case IEEE1284_MODE_NIBBLE
:
326 case IEEE1284_MODE_BYTE
:
327 return IEEE1284_PH_REV_IDLE
;
329 return IEEE1284_PH_FWD_IDLE
;
332 static int pp_ioctl(struct inode
*inode
, struct file
*file
,
333 unsigned int cmd
, unsigned long arg
)
335 unsigned int minor
= iminor(inode
);
336 struct pp_struct
*pp
= file
->private_data
;
337 struct parport
* port
;
338 void __user
*argp
= (void __user
*)arg
;
340 /* First handle the cases that don't take arguments. */
344 struct ieee1284_info
*info
;
347 if (pp
->flags
& PP_CLAIMED
) {
348 printk (KERN_DEBUG CHRDEV
349 "%x: you've already got it!\n", minor
);
353 /* Deferred device registration. */
355 int err
= register_device (minor
, pp
);
361 ret
= parport_claim_or_block (pp
->pdev
);
365 pp
->flags
|= PP_CLAIMED
;
367 /* For interrupt-reporting to work, we need to be
368 * informed of each interrupt. */
371 /* We may need to fix up the state machine. */
372 info
= &pp
->pdev
->port
->ieee1284
;
373 pp
->saved_state
.mode
= info
->mode
;
374 pp
->saved_state
.phase
= info
->phase
;
375 info
->mode
= pp
->state
.mode
;
376 info
->phase
= pp
->state
.phase
;
377 pp
->default_inactivity
= parport_set_timeout (pp
->pdev
, 0);
378 parport_set_timeout (pp
->pdev
, pp
->default_inactivity
);
384 printk (KERN_DEBUG CHRDEV
"%x: too late for PPEXCL; "
385 "already registered\n", minor
);
386 if (pp
->flags
& PP_EXCL
)
387 /* But it's not really an error. */
389 /* There's no chance of making the driver happy. */
393 /* Just remember to register the device exclusively
394 * when we finally do the registration. */
395 pp
->flags
|= PP_EXCL
;
400 if (copy_from_user (&mode
, argp
, sizeof (mode
)))
402 /* FIXME: validate mode */
403 pp
->state
.mode
= mode
;
404 pp
->state
.phase
= init_phase (mode
);
406 if (pp
->flags
& PP_CLAIMED
) {
407 pp
->pdev
->port
->ieee1284
.mode
= mode
;
408 pp
->pdev
->port
->ieee1284
.phase
= pp
->state
.phase
;
417 if (pp
->flags
& PP_CLAIMED
) {
418 mode
= pp
->pdev
->port
->ieee1284
.mode
;
420 mode
= pp
->state
.mode
;
422 if (copy_to_user (argp
, &mode
, sizeof (mode
))) {
430 if (copy_from_user (&phase
, argp
, sizeof (phase
))) {
433 /* FIXME: validate phase */
434 pp
->state
.phase
= phase
;
436 if (pp
->flags
& PP_CLAIMED
) {
437 pp
->pdev
->port
->ieee1284
.phase
= phase
;
446 if (pp
->flags
& PP_CLAIMED
) {
447 phase
= pp
->pdev
->port
->ieee1284
.phase
;
449 phase
= pp
->state
.phase
;
451 if (copy_to_user (argp
, &phase
, sizeof (phase
))) {
460 port
= parport_find_number (minor
);
465 if (copy_to_user (argp
, &modes
, sizeof (modes
))) {
474 if (copy_from_user (&uflags
, argp
, sizeof (uflags
))) {
477 pp
->flags
&= ~PP_FLAGMASK
;
478 pp
->flags
|= (uflags
& PP_FLAGMASK
);
485 uflags
= pp
->flags
& PP_FLAGMASK
;
486 if (copy_to_user (argp
, &uflags
, sizeof (uflags
))) {
493 /* Everything else requires the port to be claimed, so check
495 if ((pp
->flags
& PP_CLAIMED
) == 0) {
496 printk (KERN_DEBUG CHRDEV
"%x: claim the port first\n",
501 port
= pp
->pdev
->port
;
503 struct ieee1284_info
*info
;
508 struct timeval par_timeout
;
512 reg
= parport_read_status (port
);
513 if (copy_to_user (argp
, ®
, sizeof (reg
)))
517 reg
= parport_read_data (port
);
518 if (copy_to_user (argp
, ®
, sizeof (reg
)))
522 reg
= parport_read_control (port
);
523 if (copy_to_user (argp
, ®
, sizeof (reg
)))
527 parport_yield_blocking (pp
->pdev
);
531 /* Save the state machine's state. */
532 info
= &pp
->pdev
->port
->ieee1284
;
533 pp
->state
.mode
= info
->mode
;
534 pp
->state
.phase
= info
->phase
;
535 info
->mode
= pp
->saved_state
.mode
;
536 info
->phase
= pp
->saved_state
.phase
;
537 parport_release (pp
->pdev
);
538 pp
->flags
&= ~PP_CLAIMED
;
542 if (copy_from_user (®
, argp
, sizeof (reg
)))
544 parport_write_control (port
, reg
);
548 if (copy_from_user (®
, argp
, sizeof (reg
)))
550 parport_write_data (port
, reg
);
554 if (copy_from_user (&mask
, argp
,
557 if (copy_from_user (®
, 1 + (unsigned char __user
*) arg
,
560 parport_frob_control (port
, mask
, reg
);
564 if (copy_from_user (&mode
, argp
, sizeof (mode
)))
567 port
->ops
->data_reverse (port
);
569 port
->ops
->data_forward (port
);
573 if (copy_from_user (&mode
, argp
, sizeof (mode
)))
575 switch ((ret
= parport_negotiate (port
, mode
))) {
577 case -1: /* handshake failed, peripheral not IEEE 1284 */
580 case 1: /* handshake succeeded, peripheral rejected mode */
588 if (copy_from_user (®
, argp
, sizeof (reg
)))
591 /* Remember what to set the control lines to, for next
592 * time we get an interrupt. */
598 ret
= atomic_read (&pp
->irqc
);
599 if (copy_to_user (argp
, &ret
, sizeof (ret
)))
601 atomic_sub (ret
, &pp
->irqc
);
605 if (copy_from_user (&par_timeout
, argp
, sizeof(struct timeval
))) {
608 /* Convert to jiffies, place in pp->pdev->timeout */
609 if ((par_timeout
.tv_sec
< 0) || (par_timeout
.tv_usec
< 0)) {
612 to_jiffies
= ROUND_UP(par_timeout
.tv_usec
, 1000000/HZ
);
613 to_jiffies
+= par_timeout
.tv_sec
* (long)HZ
;
614 if (to_jiffies
<= 0) {
617 pp
->pdev
->timeout
= to_jiffies
;
621 to_jiffies
= pp
->pdev
->timeout
;
622 par_timeout
.tv_sec
= to_jiffies
/ HZ
;
623 par_timeout
.tv_usec
= (to_jiffies
% (long)HZ
) * (1000000/HZ
);
624 if (copy_to_user (argp
, &par_timeout
, sizeof(struct timeval
)))
629 printk (KERN_DEBUG CHRDEV
"%x: What? (cmd=0x%x)\n", minor
,
634 /* Keep the compiler happy */
638 static int pp_open (struct inode
* inode
, struct file
* file
)
640 unsigned int minor
= iminor(inode
);
641 struct pp_struct
*pp
;
643 if (minor
>= PARPORT_MAX
)
646 pp
= kmalloc (sizeof (struct pp_struct
), GFP_KERNEL
);
650 pp
->state
.mode
= IEEE1284_MODE_COMPAT
;
651 pp
->state
.phase
= init_phase (pp
->state
.mode
);
654 atomic_set (&pp
->irqc
, 0);
655 init_waitqueue_head (&pp
->irq_wait
);
657 /* Defer the actual device registration until the first claim.
658 * That way, we know whether or not the driver wants to have
659 * exclusive access to the port (PPEXCL).
662 file
->private_data
= pp
;
667 static int pp_release (struct inode
* inode
, struct file
* file
)
669 unsigned int minor
= iminor(inode
);
670 struct pp_struct
*pp
= file
->private_data
;
674 if (!(pp
->flags
& PP_CLAIMED
) && pp
->pdev
&&
675 (pp
->state
.mode
!= IEEE1284_MODE_COMPAT
)) {
676 struct ieee1284_info
*info
;
678 /* parport released, but not in compatibility mode */
679 parport_claim_or_block (pp
->pdev
);
680 pp
->flags
|= PP_CLAIMED
;
681 info
= &pp
->pdev
->port
->ieee1284
;
682 pp
->saved_state
.mode
= info
->mode
;
683 pp
->saved_state
.phase
= info
->phase
;
684 info
->mode
= pp
->state
.mode
;
685 info
->phase
= pp
->state
.phase
;
687 } else if ((pp
->flags
& PP_CLAIMED
) && pp
->pdev
&&
688 (pp
->pdev
->port
->ieee1284
.mode
!= IEEE1284_MODE_COMPAT
)) {
692 parport_negotiate (pp
->pdev
->port
, IEEE1284_MODE_COMPAT
);
693 printk (KERN_DEBUG CHRDEV
694 "%x: negotiated back to compatibility mode because "
695 "user-space forgot\n", minor
);
698 if (pp
->flags
& PP_CLAIMED
) {
699 struct ieee1284_info
*info
;
701 info
= &pp
->pdev
->port
->ieee1284
;
702 pp
->state
.mode
= info
->mode
;
703 pp
->state
.phase
= info
->phase
;
704 info
->mode
= pp
->saved_state
.mode
;
705 info
->phase
= pp
->saved_state
.phase
;
706 parport_release (pp
->pdev
);
707 if (compat_negot
!= 1) {
708 printk (KERN_DEBUG CHRDEV
"%x: released pardevice "
709 "because user-space forgot\n", minor
);
714 const char *name
= pp
->pdev
->name
;
715 parport_unregister_device (pp
->pdev
);
718 printk (KERN_DEBUG CHRDEV
"%x: unregistered pardevice\n",
727 /* No kernel lock held - fine */
728 static unsigned int pp_poll (struct file
* file
, poll_table
* wait
)
730 struct pp_struct
*pp
= file
->private_data
;
731 unsigned int mask
= 0;
733 poll_wait (file
, &pp
->irq_wait
, wait
);
734 if (atomic_read (&pp
->irqc
))
735 mask
|= POLLIN
| POLLRDNORM
;
740 static struct class_simple
*ppdev_class
;
742 static struct file_operations pp_fops
= {
743 .owner
= THIS_MODULE
,
750 .release
= pp_release
,
753 static void pp_attach(struct parport
*port
)
755 class_simple_device_add(ppdev_class
, MKDEV(PP_MAJOR
, port
->number
),
756 NULL
, "parport%d", port
->number
);
759 static void pp_detach(struct parport
*port
)
761 class_simple_device_remove(MKDEV(PP_MAJOR
, port
->number
));
764 static struct parport_driver pp_driver
= {
770 static int __init
ppdev_init (void)
774 if (register_chrdev (PP_MAJOR
, CHRDEV
, &pp_fops
)) {
775 printk (KERN_WARNING CHRDEV
": unable to get major %d\n",
779 ppdev_class
= class_simple_create(THIS_MODULE
, CHRDEV
);
780 if (IS_ERR(ppdev_class
)) {
781 err
= PTR_ERR(ppdev_class
);
784 devfs_mk_dir("parports");
785 for (i
= 0; i
< PARPORT_MAX
; i
++) {
786 devfs_mk_cdev(MKDEV(PP_MAJOR
, i
),
787 S_IFCHR
| S_IRUGO
| S_IWUGO
, "parports/%d", i
);
789 if (parport_register_driver(&pp_driver
)) {
790 printk (KERN_WARNING CHRDEV
": unable to register with parport\n");
794 printk (KERN_INFO PP_VERSION
"\n");
798 for (i
= 0; i
< PARPORT_MAX
; i
++)
799 devfs_remove("parports/%d", i
);
800 devfs_remove("parports");
801 class_simple_destroy(ppdev_class
);
803 unregister_chrdev(PP_MAJOR
, CHRDEV
);
808 static void __exit
ppdev_cleanup (void)
811 /* Clean up all parport stuff */
812 for (i
= 0; i
< PARPORT_MAX
; i
++)
813 devfs_remove("parports/%d", i
);
814 parport_unregister_driver(&pp_driver
);
815 devfs_remove("parports");
816 class_simple_destroy(ppdev_class
);
817 unregister_chrdev (PP_MAJOR
, CHRDEV
);
820 module_init(ppdev_init
);
821 module_exit(ppdev_cleanup
);
823 MODULE_LICENSE("GPL");
824 MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR
);