kcomedilib_main.c revision 197c82bf25b9e379cb5646561be1a727ab9e84a7 
1/*
2    kcomedilib/kcomedilib.c
3    a comedlib interface for kernel modules
4
5    COMEDI - Linux Control and Measurement Device Interface
6    Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
7
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 2 of the License, or
11    (at your option) any later version.
12
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17
18    You should have received a copy of the GNU General Public License
19    along with this program; if not, write to the Free Software
20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21
22*/
23
24#define __NO_VERSION__
25#include <linux/module.h>
26
27#include <linux/errno.h>
28#include <linux/kernel.h>
29#include <linux/sched.h>
30#include <linux/fcntl.h>
31#include <linux/delay.h>
32#include <linux/ioport.h>
33#include <linux/mm.h>
34#include <linux/slab.h>
35#include <asm/io.h>
36
37#include "../comedi.h"
38#include "../comedilib.h"
39#include "../comedidev.h"
40
41MODULE_AUTHOR("David Schleef <ds@schleef.org>");
42MODULE_DESCRIPTION("Comedi kernel library");
43MODULE_LICENSE("GPL");
44
45comedi_t *comedi_open(const char *filename)
46{
47	struct comedi_device_file_info *dev_file_info;
48	comedi_device *dev;
49	unsigned int minor;
50
51	if (strncmp(filename, "/dev/comedi", 11) != 0)
52		return NULL;
53
54	minor = simple_strtoul(filename + 11, NULL, 0);
55
56	if (minor >= COMEDI_NUM_BOARD_MINORS)
57		return NULL;
58
59	dev_file_info = comedi_get_device_file_info(minor);
60	if (dev_file_info == NULL)
61		return NULL;
62	dev = dev_file_info->device;
63
64	if (dev == NULL || !dev->attached)
65		return NULL;
66
67	if (!try_module_get(dev->driver->module))
68		return NULL;
69
70	return (comedi_t *) dev;
71}
72
73comedi_t *comedi_open_old(unsigned int minor)
74{
75	struct comedi_device_file_info *dev_file_info;
76	comedi_device *dev;
77
78	if (minor >= COMEDI_NUM_MINORS)
79		return NULL;
80
81	dev_file_info = comedi_get_device_file_info(minor);
82	if (dev_file_info == NULL)
83		return NULL;
84	dev = dev_file_info->device;
85
86	if (dev == NULL || !dev->attached)
87		return NULL;
88
89	return (comedi_t *) dev;
90}
91
92int comedi_close(comedi_t *d)
93{
94	comedi_device *dev = (comedi_device *) d;
95
96	module_put(dev->driver->module);
97
98	return 0;
99}
100
101int comedi_loglevel(int newlevel)
102{
103	return 0;
104}
105
106void comedi_perror(const char *message)
107{
108	rt_printk("%s: unknown error\n", message);
109}
110
111char *comedi_strerror(int err)
112{
113	return "unknown error";
114}
115
116int comedi_fileno(comedi_t *d)
117{
118	comedi_device *dev = (comedi_device *) d;
119
120	/* return something random */
121	return dev->minor;
122}
123
124int comedi_command(comedi_t *d, comedi_cmd *cmd)
125{
126	comedi_device *dev = (comedi_device *) d;
127	comedi_subdevice *s;
128	comedi_async *async;
129	unsigned runflags;
130
131	if (cmd->subdev >= dev->n_subdevices)
132		return -ENODEV;
133
134	s = dev->subdevices + cmd->subdev;
135	if (s->type == COMEDI_SUBD_UNUSED)
136		return -EIO;
137
138	async = s->async;
139	if (async == NULL)
140		return -ENODEV;
141
142	if (s->busy)
143		return -EBUSY;
144	s->busy = d;
145
146	if (async->cb_mask & COMEDI_CB_EOS)
147		cmd->flags |= TRIG_WAKE_EOS;
148
149	async->cmd = *cmd;
150
151	runflags = SRF_RUNNING;
152
153#ifdef CONFIG_COMEDI_RT
154	if (comedi_switch_to_rt(dev) == 0)
155		runflags |= SRF_RT;
156#endif
157	comedi_set_subdevice_runflags(s, ~0, runflags);
158
159	comedi_reset_async_buf(async);
160
161	return s->do_cmd(dev, s);
162}
163
164int comedi_command_test(comedi_t *d, comedi_cmd *cmd)
165{
166	comedi_device *dev = (comedi_device *) d;
167	comedi_subdevice *s;
168
169	if (cmd->subdev >= dev->n_subdevices)
170		return -ENODEV;
171
172	s = dev->subdevices + cmd->subdev;
173	if (s->type == COMEDI_SUBD_UNUSED)
174		return -EIO;
175
176	if (s->async == NULL)
177		return -ENODEV;
178
179	return s->do_cmdtest(dev, s, cmd);
180}
181
182/*
183 *	COMEDI_INSN
184 *	perform an instruction
185 */
186int comedi_do_insn(comedi_t *d, comedi_insn *insn)
187{
188	comedi_device *dev = (comedi_device *) d;
189	comedi_subdevice *s;
190	int ret = 0;
191
192	if (insn->insn & INSN_MASK_SPECIAL) {
193		switch (insn->insn) {
194		case INSN_GTOD:
195			{
196				struct timeval tv;
197
198				do_gettimeofday(&tv);
199				insn->data[0] = tv.tv_sec;
200				insn->data[1] = tv.tv_usec;
201				ret = 2;
202
203				break;
204			}
205		case INSN_WAIT:
206			/* XXX isn't the value supposed to be nanosecs? */
207			if (insn->n != 1 || insn->data[0] >= 100) {
208				ret = -EINVAL;
209				break;
210			}
211			comedi_udelay(insn->data[0]);
212			ret = 1;
213			break;
214		case INSN_INTTRIG:
215			if (insn->n != 1) {
216				ret = -EINVAL;
217				break;
218			}
219			if (insn->subdev >= dev->n_subdevices) {
220				rt_printk("%d not usable subdevice\n",
221					insn->subdev);
222				ret = -EINVAL;
223				break;
224			}
225			s = dev->subdevices + insn->subdev;
226			if (!s->async) {
227				rt_printk("no async\n");
228				ret = -EINVAL;
229				break;
230			}
231			if (!s->async->inttrig) {
232				rt_printk("no inttrig\n");
233				ret = -EAGAIN;
234				break;
235			}
236			ret = s->async->inttrig(dev, s, insn->data[0]);
237			if (ret >= 0)
238				ret = 1;
239			break;
240		default:
241			ret = -EINVAL;
242		}
243	} else {
244		/* a subdevice instruction */
245		if (insn->subdev >= dev->n_subdevices) {
246			ret = -EINVAL;
247			goto error;
248		}
249		s = dev->subdevices + insn->subdev;
250
251		if (s->type == COMEDI_SUBD_UNUSED) {
252			rt_printk("%d not useable subdevice\n", insn->subdev);
253			ret = -EIO;
254			goto error;
255		}
256
257		/* XXX check lock */
258
259		ret = check_chanlist(s, 1, &insn->chanspec);
260		if (ret < 0) {
261			rt_printk("bad chanspec\n");
262			ret = -EINVAL;
263			goto error;
264		}
265
266		if (s->busy) {
267			ret = -EBUSY;
268			goto error;
269		}
270		s->busy = d;
271
272		switch (insn->insn) {
273		case INSN_READ:
274			ret = s->insn_read(dev, s, insn, insn->data);
275			break;
276		case INSN_WRITE:
277			ret = s->insn_write(dev, s, insn, insn->data);
278			break;
279		case INSN_BITS:
280			ret = s->insn_bits(dev, s, insn, insn->data);
281			break;
282		case INSN_CONFIG:
283			/* XXX should check instruction length */
284			ret = s->insn_config(dev, s, insn, insn->data);
285			break;
286		default:
287			ret = -EINVAL;
288			break;
289		}
290
291		s->busy = NULL;
292	}
293	if (ret < 0)
294		goto error;
295#if 0
296	/* XXX do we want this? -- abbotti #if'ed it out for now. */
297	if (ret != insn->n) {
298		rt_printk("BUG: result of insn != insn.n\n");
299		ret = -EINVAL;
300		goto error;
301	}
302#endif
303      error:
304
305	return ret;
306}
307
308/*
309	COMEDI_LOCK
310	lock subdevice
311
312	arg:
313		subdevice number
314
315	reads:
316		none
317
318	writes:
319		none
320
321	necessary locking:
322	- ioctl/rt lock  (this type)
323	- lock while subdevice busy
324	- lock while subdevice being programmed
325
326*/
327int comedi_lock(comedi_t *d, unsigned int subdevice)
328{
329	comedi_device *dev = (comedi_device *) d;
330	comedi_subdevice *s;
331	unsigned long flags;
332	int ret = 0;
333
334	if (subdevice >= dev->n_subdevices) {
335		return -EINVAL;
336	}
337	s = dev->subdevices + subdevice;
338
339	comedi_spin_lock_irqsave(&s->spin_lock, flags);
340
341	if (s->busy) {
342		ret = -EBUSY;
343	} else {
344		if (s->lock) {
345			ret = -EBUSY;
346		} else {
347			s->lock = d;
348		}
349	}
350
351	comedi_spin_unlock_irqrestore(&s->spin_lock, flags);
352
353	return ret;
354}
355
356/*
357	COMEDI_UNLOCK
358	unlock subdevice
359
360	arg:
361		subdevice number
362
363	reads:
364		none
365
366	writes:
367		none
368
369*/
370int comedi_unlock(comedi_t *d, unsigned int subdevice)
371{
372	comedi_device *dev = (comedi_device *) d;
373	comedi_subdevice *s;
374	unsigned long flags;
375	comedi_async *async;
376	int ret;
377
378	if (subdevice >= dev->n_subdevices) {
379		return -EINVAL;
380	}
381	s = dev->subdevices + subdevice;
382
383	async = s->async;
384
385	comedi_spin_lock_irqsave(&s->spin_lock, flags);
386
387	if (s->busy) {
388		ret = -EBUSY;
389	} else if (s->lock && s->lock != (void *)d) {
390		ret = -EACCES;
391	} else {
392		s->lock = NULL;
393
394		if (async) {
395			async->cb_mask = 0;
396			async->cb_func = NULL;
397			async->cb_arg = NULL;
398		}
399
400		ret = 0;
401	}
402
403	comedi_spin_unlock_irqrestore(&s->spin_lock, flags);
404
405	return ret;
406}
407
408/*
409	COMEDI_CANCEL
410	cancel acquisition ioctl
411
412	arg:
413		subdevice number
414
415	reads:
416		nothing
417
418	writes:
419		nothing
420
421*/
422int comedi_cancel(comedi_t *d, unsigned int subdevice)
423{
424	comedi_device *dev = (comedi_device *) d;
425	comedi_subdevice *s;
426	int ret = 0;
427
428	if (subdevice >= dev->n_subdevices) {
429		return -EINVAL;
430	}
431	s = dev->subdevices + subdevice;
432
433	if (s->lock && s->lock != d)
434		return -EACCES;
435
436#if 0
437	if (!s->busy)
438		return 0;
439
440	if (s->busy != d)
441		return -EBUSY;
442#endif
443
444	if (!s->cancel || !s->async)
445		return -EINVAL;
446
447	ret = s->cancel(dev, s);
448
449	if (ret)
450		return ret;
451
452#ifdef CONFIG_COMEDI_RT
453	if (comedi_get_subdevice_runflags(s) & SRF_RT) {
454		comedi_switch_to_non_rt(dev);
455	}
456#endif
457	comedi_set_subdevice_runflags(s, SRF_RUNNING | SRF_RT, 0);
458	s->async->inttrig = NULL;
459	s->busy = NULL;
460
461	return 0;
462}
463
464/*
465   registration of callback functions
466 */
467int comedi_register_callback(comedi_t *d, unsigned int subdevice,
468	unsigned int mask, int (*cb) (unsigned int, void *), void *arg)
469{
470	comedi_device *dev = (comedi_device *) d;
471	comedi_subdevice *s;
472	comedi_async *async;
473
474	if (subdevice >= dev->n_subdevices) {
475		return -EINVAL;
476	}
477	s = dev->subdevices + subdevice;
478
479	async = s->async;
480	if (s->type == COMEDI_SUBD_UNUSED || !async)
481		return -EIO;
482
483	/* are we locked? (ioctl lock) */
484	if (s->lock && s->lock != d)
485		return -EACCES;
486
487	/* are we busy? */
488	if (s->busy)
489		return -EBUSY;
490
491	if (!mask) {
492		async->cb_mask = 0;
493		async->cb_func = NULL;
494		async->cb_arg = NULL;
495	} else {
496		async->cb_mask = mask;
497		async->cb_func = cb;
498		async->cb_arg = arg;
499	}
500
501	return 0;
502}
503
504int comedi_poll(comedi_t *d, unsigned int subdevice)
505{
506	comedi_device *dev = (comedi_device *) d;
507	comedi_subdevice *s = dev->subdevices;
508	comedi_async *async;
509
510	if (subdevice >= dev->n_subdevices) {
511		return -EINVAL;
512	}
513	s = dev->subdevices + subdevice;
514
515	async = s->async;
516	if (s->type == COMEDI_SUBD_UNUSED || !async)
517		return -EIO;
518
519	/* are we locked? (ioctl lock) */
520	if (s->lock && s->lock != d)
521		return -EACCES;
522
523	/* are we running? XXX wrong? */
524	if (!s->busy)
525		return -EIO;
526
527	return s->poll(dev, s);
528}
529
530/* WARNING: not portable */
531int comedi_map(comedi_t *d, unsigned int subdevice, void *ptr)
532{
533	comedi_device *dev = (comedi_device *) d;
534	comedi_subdevice *s;
535
536	if (subdevice >= dev->n_subdevices) {
537		return -EINVAL;
538	}
539	s = dev->subdevices + subdevice;
540
541	if (!s->async)
542		return -EINVAL;
543
544	if (ptr) {
545		*((void **)ptr) = s->async->prealloc_buf;
546	}
547
548	/* XXX no reference counting */
549
550	return 0;
551}
552
553/* WARNING: not portable */
554int comedi_unmap(comedi_t *d, unsigned int subdevice)
555{
556	comedi_device *dev = (comedi_device *) d;
557	comedi_subdevice *s;
558
559	if (subdevice >= dev->n_subdevices) {
560		return -EINVAL;
561	}
562	s = dev->subdevices + subdevice;
563
564	if (!s->async)
565		return -EINVAL;
566
567	/* XXX no reference counting */
568
569	return 0;
570}
571