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-rw-r--r--drivers/char/tipar.c557
1 files changed, 0 insertions, 557 deletions
diff --git a/drivers/char/tipar.c b/drivers/char/tipar.c
deleted file mode 100644
index cef55c40654f..000000000000
--- a/drivers/char/tipar.c
+++ /dev/null
@@ -1,557 +0,0 @@
1/* Hey EMACS -*- linux-c -*-
2 *
3 * tipar - low level driver for handling a parallel link cable designed
4 * for Texas Instruments graphing calculators (http://lpg.ticalc.org).
5 * A part of the TiLP project.
6 *
7 * Copyright (C) 2000-2002, Romain Lievin <roms@lpg.ticalc.org>
8 * under the terms of the GNU General Public License.
9 *
10 * Various fixes & clean-up from the Linux Kernel Mailing List
11 * (Alan Cox, Richard B. Johnson, Christoph Hellwig).
12 */
13
14/* This driver should, in theory, work with any parallel port that has an
15 * appropriate low-level driver; all I/O is done through the parport
16 * abstraction layer.
17 *
18 * If this driver is built into the kernel, you can configure it using the
19 * kernel command-line. For example:
20 *
21 * tipar=timeout,delay (set timeout and delay)
22 *
23 * If the driver is loaded as a module, similar functionality is available
24 * using module parameters. The equivalent of the above commands would be:
25 *
26 * # insmod tipar timeout=15 delay=10
27 */
28
29/* COMPATIBILITY WITH OLD KERNELS
30 *
31 * Usually, parallel cables were bound to ports at
32 * particular I/O addresses, as follows:
33 *
34 * tipar0 0x378
35 * tipar1 0x278
36 * tipar2 0x3bc
37 *
38 *
39 * This driver, by default, binds tipar devices according to parport and
40 * the minor number.
41 *
42 */
43#undef DEBUG /* change to #define to get debugging
44 * output - for pr_debug() */
45#include <linux/module.h>
46#include <linux/types.h>
47#include <linux/errno.h>
48#include <linux/kernel.h>
49#include <linux/sched.h>
50#include <linux/delay.h>
51#include <linux/fcntl.h>
52#include <linux/fs.h>
53#include <linux/init.h>
54#include <asm/uaccess.h>
55#include <linux/ioport.h>
56#include <asm/io.h>
57#include <linux/bitops.h>
58#include <linux/parport.h> /* Our code depend on parport */
59#include <linux/device.h>
60
61/*
62 * TI definitions
63 */
64#include <linux/ticable.h>
65
66/*
67 * Version Information
68 */
69#define DRIVER_VERSION "1.19"
70#define DRIVER_AUTHOR "Romain Lievin <roms@lpg.ticalc.org>"
71#define DRIVER_DESC "Device driver for TI/PC parallel link cables"
72#define DRIVER_LICENSE "GPL"
73
74#define VERSION(ver,rel,seq) (((ver)<<16) | ((rel)<<8) | (seq))
75
76/* ----- global variables --------------------------------------------- */
77
78struct tipar_struct {
79 struct pardevice *dev; /* Parport device entry */
80};
81
82#define PP_NO 3
83static struct tipar_struct table[PP_NO];
84
85static int delay = IO_DELAY; /* inter-bit delay in microseconds */
86static int timeout = TIMAXTIME; /* timeout in tenth of seconds */
87
88static unsigned int tp_count; /* tipar count */
89static unsigned long opened; /* opened devices */
90
91static struct class *tipar_class;
92
93/* --- macros for parport access -------------------------------------- */
94
95#define r_dtr(x) (parport_read_data(table[(x)].dev->port))
96#define r_str(x) (parport_read_status(table[(x)].dev->port))
97#define w_ctr(x,y) (parport_write_control(table[(x)].dev->port, (y)))
98#define w_dtr(x,y) (parport_write_data(table[(x)].dev->port, (y)))
99
100/* --- setting states on the D-bus with the right timing: ------------- */
101
102static inline void
103outbyte(int value, int minor)
104{
105 w_dtr(minor, value);
106}
107
108static inline int
109inbyte(int minor)
110{
111 return (r_str(minor));
112}
113
114static inline void
115init_ti_parallel(int minor)
116{
117 outbyte(3, minor);
118}
119
120/* ----- global defines ----------------------------------------------- */
121
122#define START(x) { x = jiffies + (HZ * timeout) / 10; }
123#define WAIT(x) { \
124 if (time_before((x), jiffies)) return -1; \
125 if (need_resched()) schedule(); }
126
127/* ----- D-bus bit-banging functions ---------------------------------- */
128
129/* D-bus protocol (45kbit/s max):
130 1 0 0
131 _______ ______|______ __________|________ __________
132Red : ________ | ____ | ____
133 _ ____________|________ ______|__________ _____
134White: ________ | ______ | _______
135*/
136
137/* Try to transmit a byte on the specified port (-1 if error). */
138static int
139put_ti_parallel(int minor, unsigned char data)
140{
141 unsigned int bit;
142 unsigned long max;
143
144 for (bit = 0; bit < 8; bit++) {
145 if (data & 1) {
146 outbyte(2, minor);
147 START(max);
148 do {
149 WAIT(max);
150 } while (inbyte(minor) & 0x10);
151
152 outbyte(3, minor);
153 START(max);
154 do {
155 WAIT(max);
156 } while (!(inbyte(minor) & 0x10));
157 } else {
158 outbyte(1, minor);
159 START(max);
160 do {
161 WAIT(max);
162 } while (inbyte(minor) & 0x20);
163
164 outbyte(3, minor);
165 START(max);
166 do {
167 WAIT(max);
168 } while (!(inbyte(minor) & 0x20));
169 }
170
171 data >>= 1;
172 udelay(delay);
173
174 if (need_resched())
175 schedule();
176 }
177
178 return 0;
179}
180
181/* Receive a byte on the specified port or -1 if error. */
182static int
183get_ti_parallel(int minor)
184{
185 unsigned int bit;
186 unsigned char v, data = 0;
187 unsigned long max;
188
189 for (bit = 0; bit < 8; bit++) {
190 START(max);
191 do {
192 WAIT(max);
193 } while ((v = inbyte(minor) & 0x30) == 0x30);
194
195 if (v == 0x10) {
196 data = (data >> 1) | 0x80;
197 outbyte(1, minor);
198 START(max);
199 do {
200 WAIT(max);
201 } while (!(inbyte(minor) & 0x20));
202 outbyte(3, minor);
203 } else {
204 data = data >> 1;
205 outbyte(2, minor);
206 START(max);
207 do {
208 WAIT(max);
209 } while (!(inbyte(minor) & 0x10));
210 outbyte(3, minor);
211 }
212
213 udelay(delay);
214 if (need_resched())
215 schedule();
216 }
217
218 return (int) data;
219}
220
221/* Try to detect a parallel link cable on the specified port */
222static int
223probe_ti_parallel(int minor)
224{
225 int i;
226 int seq[] = { 0x00, 0x20, 0x10, 0x30 };
227 int data;
228
229 for (i = 3; i >= 0; i--) {
230 outbyte(3, minor);
231 outbyte(i, minor);
232 udelay(delay);
233 data = inbyte(minor) & 0x30;
234 pr_debug("tipar: Probing -> %i: 0x%02x 0x%02x\n", i,
235 data, seq[i]);
236 if (data != seq[i]) {
237 outbyte(3, minor);
238 return -1;
239 }
240 }
241
242 outbyte(3, minor);
243 return 0;
244}
245
246/* ----- kernel module functions--------------------------------------- */
247
248static int
249tipar_open(struct inode *inode, struct file *file)
250{
251 unsigned int minor = iminor(inode) - TIPAR_MINOR;
252
253 if (tp_count == 0 || minor > tp_count - 1)
254 return -ENXIO;
255
256 if (test_and_set_bit(minor, &opened))
257 return -EBUSY;
258
259 if (!table[minor].dev) {
260 printk(KERN_ERR "%s: NULL device for minor %u\n",
261 __FUNCTION__, minor);
262 return -ENXIO;
263 }
264 parport_claim_or_block(table[minor].dev);
265 init_ti_parallel(minor);
266 parport_release(table[minor].dev);
267
268 return nonseekable_open(inode, file);
269}
270
271static int
272tipar_close(struct inode *inode, struct file *file)
273{
274 unsigned int minor = iminor(inode) - TIPAR_MINOR;
275
276 if (minor > tp_count - 1)
277 return -ENXIO;
278
279 clear_bit(minor, &opened);
280
281 return 0;
282}
283
284static ssize_t
285tipar_write (struct file *file, const char __user *buf, size_t count,
286 loff_t * ppos)
287{
288 unsigned int minor = iminor(file->f_path.dentry->d_inode) - TIPAR_MINOR;
289 ssize_t n;
290
291 parport_claim_or_block(table[minor].dev);
292
293 for (n = 0; n < count; n++) {
294 unsigned char b;
295
296 if (get_user(b, buf + n)) {
297 n = -EFAULT;
298 goto out;
299 }
300
301 if (put_ti_parallel(minor, b) == -1) {
302 init_ti_parallel(minor);
303 n = -ETIMEDOUT;
304 goto out;
305 }
306 }
307 out:
308 parport_release(table[minor].dev);
309 return n;
310}
311
312static ssize_t
313tipar_read(struct file *file, char __user *buf, size_t count, loff_t * ppos)
314{
315 int b = 0;
316 unsigned int minor = iminor(file->f_path.dentry->d_inode) - TIPAR_MINOR;
317 ssize_t retval = 0;
318 ssize_t n = 0;
319
320 if (count == 0)
321 return 0;
322
323 parport_claim_or_block(table[minor].dev);
324
325 while (n < count) {
326 b = get_ti_parallel(minor);
327 if (b == -1) {
328 init_ti_parallel(minor);
329 retval = -ETIMEDOUT;
330 goto out;
331 } else {
332 if (put_user(b, buf + n)) {
333 retval = -EFAULT;
334 break;
335 } else
336 retval = ++n;
337 }
338
339 /* Non-blocking mode : try again ! */
340 if (file->f_flags & O_NONBLOCK) {
341 retval = -EAGAIN;
342 goto out;
343 }
344
345 /* Signal pending, try again ! */
346 if (signal_pending(current)) {
347 retval = -ERESTARTSYS;
348 goto out;
349 }
350
351 if (need_resched())
352 schedule();
353 }
354
355 out:
356 parport_release(table[minor].dev);
357 return retval;
358}
359
360static int
361tipar_ioctl(struct inode *inode, struct file *file,
362 unsigned int cmd, unsigned long arg)
363{
364 int retval = 0;
365
366 switch (cmd) {
367 case IOCTL_TIPAR_DELAY:
368 delay = (int)arg; //get_user(delay, &arg);
369 break;
370 case IOCTL_TIPAR_TIMEOUT:
371 if (arg != 0)
372 timeout = (int)arg;
373 else
374 retval = -EINVAL;
375 break;
376 default:
377 retval = -ENOTTY;
378 break;
379 }
380
381 return retval;
382}
383
384/* ----- kernel module registering ------------------------------------ */
385
386static const struct file_operations tipar_fops = {
387 .owner = THIS_MODULE,
388 .llseek = no_llseek,
389 .read = tipar_read,
390 .write = tipar_write,
391 .ioctl = tipar_ioctl,
392 .open = tipar_open,
393 .release = tipar_close,
394};
395
396/* --- initialisation code ------------------------------------- */
397
398#ifndef MODULE
399/* You must set these - there is no sane way to probe for this cable.
400 * You can use 'tipar=timeout,delay' to set these now. */
401static int __init
402tipar_setup(char *str)
403{
404 int ints[3];
405
406 str = get_options(str, ARRAY_SIZE(ints), ints);
407
408 if (ints[0] > 0) {
409 if (ints[1] != 0)
410 timeout = ints[1];
411 else
412 printk(KERN_WARNING "tipar: bad timeout value (0), "
413 "using default value instead");
414 if (ints[0] > 1) {
415 delay = ints[2];
416 }
417 }
418
419 return 1;
420}
421#endif
422
423/*
424 * Register our module into parport.
425 * Pass also 2 callbacks functions to parport: a pre-emptive function and an
426 * interrupt handler function (unused).
427 * Display a message such "tipar0: using parport0 (polling)".
428 */
429static int
430tipar_register(int nr, struct parport *port)
431{
432 int err = 0;
433
434 /* Register our module into parport */
435 table[nr].dev = parport_register_device(port, "tipar",
436 NULL, NULL, NULL, 0,
437 (void *) &table[nr]);
438
439 if (table[nr].dev == NULL) {
440 err = 1;
441 goto out;
442 }
443
444 device_create(tipar_class, port->dev, MKDEV(TIPAR_MAJOR,
445 TIPAR_MINOR + nr), "par%d", nr);
446
447 /* Display informations */
448 pr_info("tipar%d: using %s (%s)\n", nr, port->name, (port->irq ==
449 PARPORT_IRQ_NONE) ? "polling" : "interrupt-driven");
450
451 if (probe_ti_parallel(nr) != -1)
452 pr_info("tipar%d: link cable found\n", nr);
453 else
454 pr_info("tipar%d: link cable not found\n", nr);
455
456 err = 0;
457
458out:
459 return err;
460}
461
462static void
463tipar_attach(struct parport *port)
464{
465 if (tp_count == PP_NO) {
466 pr_info("tipar: ignoring parallel port (max. %d)\n", PP_NO);
467 return;
468 }
469
470 if (!tipar_register(tp_count, port))
471 tp_count++;
472}
473
474static void
475tipar_detach(struct parport *port)
476{
477 /* Nothing to do */
478}
479
480static struct parport_driver tipar_driver = {
481 .name = "tipar",
482 .attach = tipar_attach,
483 .detach = tipar_detach,
484};
485
486static int __init
487tipar_init_module(void)
488{
489 int err = 0;
490
491 pr_info("tipar: parallel link cable driver, version %s\n",
492 DRIVER_VERSION);
493
494 if (register_chrdev(TIPAR_MAJOR, "tipar", &tipar_fops)) {
495 printk(KERN_ERR "tipar: unable to get major %d\n", TIPAR_MAJOR);
496 err = -EIO;
497 goto out;
498 }
499
500 tipar_class = class_create(THIS_MODULE, "ticables");
501 if (IS_ERR(tipar_class)) {
502 err = PTR_ERR(tipar_class);
503 goto out_chrdev;
504 }
505 if (parport_register_driver(&tipar_driver)) {
506 printk(KERN_ERR "tipar: unable to register with parport\n");
507 err = -EIO;
508 goto out_class;
509 }
510
511 err = 0;
512 goto out;
513
514out_class:
515 class_destroy(tipar_class);
516
517out_chrdev:
518 unregister_chrdev(TIPAR_MAJOR, "tipar");
519out:
520 return err;
521}
522
523static void __exit
524tipar_cleanup_module(void)
525{
526 unsigned int i;
527
528 /* Unregistering module */
529 parport_unregister_driver(&tipar_driver);
530
531 unregister_chrdev(TIPAR_MAJOR, "tipar");
532
533 for (i = 0; i < PP_NO; i++) {
534 if (table[i].dev == NULL)
535 continue;
536 parport_unregister_device(table[i].dev);
537 device_destroy(tipar_class, MKDEV(TIPAR_MAJOR, i));
538 }
539 class_destroy(tipar_class);
540
541 pr_info("tipar: module unloaded\n");
542}
543
544/* --------------------------------------------------------------------- */
545
546__setup("tipar=", tipar_setup);
547module_init(tipar_init_module);
548module_exit(tipar_cleanup_module);
549
550MODULE_AUTHOR(DRIVER_AUTHOR);
551MODULE_DESCRIPTION(DRIVER_DESC);
552MODULE_LICENSE(DRIVER_LICENSE);
553
554module_param(timeout, int, 0);
555MODULE_PARM_DESC(timeout, "Timeout (default=1.5 seconds)");
556module_param(delay, int, 0);
557MODULE_PARM_DESC(delay, "Inter-bit delay (default=10 microseconds)");
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