kcomedilib_main.c revision b79a7a2089294cba254f6972e4e224fea643b84a 
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		if ((ret = check_chanlist(s, 1, &insn->chanspec)) < 0) {
260			rt_printk("bad chanspec\n");
261			ret = -EINVAL;
262			goto error;
263		}
264
265		if (s->busy) {
266			ret = -EBUSY;
267			goto error;
268		}
269		s->busy = d;
270
271		switch (insn->insn) {
272		case INSN_READ:
273			ret = s->insn_read(dev, s, insn, insn->data);
274			break;
275		case INSN_WRITE:
276			ret = s->insn_write(dev, s, insn, insn->data);
277			break;
278		case INSN_BITS:
279			ret = s->insn_bits(dev, s, insn, insn->data);
280			break;
281		case INSN_CONFIG:
282			/* XXX should check instruction length */
283			ret = s->insn_config(dev, s, insn, insn->data);
284			break;
285		default:
286			ret = -EINVAL;
287			break;
288		}
289
290		s->busy = NULL;
291	}
292	if (ret < 0)
293		goto error;
294#if 0
295	/* XXX do we want this? -- abbotti #if'ed it out for now. */
296	if (ret != insn->n) {
297		rt_printk("BUG: result of insn != insn.n\n");
298		ret = -EINVAL;
299		goto error;
300	}
301#endif
302      error:
303
304	return ret;
305}
306
307/*
308	COMEDI_LOCK
309	lock subdevice
310
311	arg:
312		subdevice number
313
314	reads:
315		none
316
317	writes:
318		none
319
320	necessary locking:
321	- ioctl/rt lock  (this type)
322	- lock while subdevice busy
323	- lock while subdevice being programmed
324
325*/
326int comedi_lock(comedi_t * d, unsigned int subdevice)
327{
328	comedi_device *dev = (comedi_device *) d;
329	comedi_subdevice *s;
330	unsigned long flags;
331	int ret = 0;
332
333	if (subdevice >= dev->n_subdevices) {
334		return -EINVAL;
335	}
336	s = dev->subdevices + subdevice;
337
338	comedi_spin_lock_irqsave(&s->spin_lock, flags);
339
340	if (s->busy) {
341		ret = -EBUSY;
342	} else {
343		if (s->lock) {
344			ret = -EBUSY;
345		} else {
346			s->lock = d;
347		}
348	}
349
350	comedi_spin_unlock_irqrestore(&s->spin_lock, flags);
351
352	return ret;
353}
354
355/*
356	COMEDI_UNLOCK
357	unlock subdevice
358
359	arg:
360		subdevice number
361
362	reads:
363		none
364
365	writes:
366		none
367
368*/
369int comedi_unlock(comedi_t * d, unsigned int subdevice)
370{
371	comedi_device *dev = (comedi_device *) d;
372	comedi_subdevice *s;
373	unsigned long flags;
374	comedi_async *async;
375	int ret;
376
377	if (subdevice >= dev->n_subdevices) {
378		return -EINVAL;
379	}
380	s = dev->subdevices + subdevice;
381
382	async = s->async;
383
384	comedi_spin_lock_irqsave(&s->spin_lock, flags);
385
386	if (s->busy) {
387		ret = -EBUSY;
388	} else if (s->lock && s->lock != (void *)d) {
389		ret = -EACCES;
390	} else {
391		s->lock = NULL;
392
393		if (async) {
394			async->cb_mask = 0;
395			async->cb_func = NULL;
396			async->cb_arg = NULL;
397		}
398
399		ret = 0;
400	}
401
402	comedi_spin_unlock_irqrestore(&s->spin_lock, flags);
403
404	return ret;
405}
406
407/*
408	COMEDI_CANCEL
409	cancel acquisition ioctl
410
411	arg:
412		subdevice number
413
414	reads:
415		nothing
416
417	writes:
418		nothing
419
420*/
421int comedi_cancel(comedi_t * d, unsigned int subdevice)
422{
423	comedi_device *dev = (comedi_device *) d;
424	comedi_subdevice *s;
425	int ret = 0;
426
427	if (subdevice >= dev->n_subdevices) {
428		return -EINVAL;
429	}
430	s = dev->subdevices + subdevice;
431
432	if (s->lock && s->lock != d)
433		return -EACCES;
434
435#if 0
436	if (!s->busy)
437		return 0;
438
439	if (s->busy != d)
440		return -EBUSY;
441#endif
442
443	if (!s->cancel || !s->async)
444		return -EINVAL;
445
446	if ((ret = s->cancel(dev, s)))
447		return ret;
448
449#ifdef CONFIG_COMEDI_RT
450	if (comedi_get_subdevice_runflags(s) & SRF_RT) {
451		comedi_switch_to_non_rt(dev);
452	}
453#endif
454	comedi_set_subdevice_runflags(s, SRF_RUNNING | SRF_RT, 0);
455	s->async->inttrig = NULL;
456	s->busy = NULL;
457
458	return 0;
459}
460
461/*
462   registration of callback functions
463 */
464int comedi_register_callback(comedi_t * d, unsigned int subdevice,
465	unsigned int mask, int (*cb) (unsigned int, void *), void *arg)
466{
467	comedi_device *dev = (comedi_device *) d;
468	comedi_subdevice *s;
469	comedi_async *async;
470
471	if (subdevice >= dev->n_subdevices) {
472		return -EINVAL;
473	}
474	s = dev->subdevices + subdevice;
475
476	async = s->async;
477	if (s->type == COMEDI_SUBD_UNUSED || !async)
478		return -EIO;
479
480	/* are we locked? (ioctl lock) */
481	if (s->lock && s->lock != d)
482		return -EACCES;
483
484	/* are we busy? */
485	if (s->busy)
486		return -EBUSY;
487
488	if (!mask) {
489		async->cb_mask = 0;
490		async->cb_func = NULL;
491		async->cb_arg = NULL;
492	} else {
493		async->cb_mask = mask;
494		async->cb_func = cb;
495		async->cb_arg = arg;
496	}
497
498	return 0;
499}
500
501int comedi_poll(comedi_t * d, unsigned int subdevice)
502{
503	comedi_device *dev = (comedi_device *) d;
504	comedi_subdevice *s = dev->subdevices;
505	comedi_async *async;
506
507	if (subdevice >= dev->n_subdevices) {
508		return -EINVAL;
509	}
510	s = dev->subdevices + subdevice;
511
512	async = s->async;
513	if (s->type == COMEDI_SUBD_UNUSED || !async)
514		return -EIO;
515
516	/* are we locked? (ioctl lock) */
517	if (s->lock && s->lock != d)
518		return -EACCES;
519
520	/* are we running? XXX wrong? */
521	if (!s->busy)
522		return -EIO;
523
524	return s->poll(dev, s);
525}
526
527/* WARNING: not portable */
528int comedi_map(comedi_t * d, unsigned int subdevice, void *ptr)
529{
530	comedi_device *dev = (comedi_device *) d;
531	comedi_subdevice *s;
532
533	if (subdevice >= dev->n_subdevices) {
534		return -EINVAL;
535	}
536	s = dev->subdevices + subdevice;
537
538	if (!s->async)
539		return -EINVAL;
540
541	if (ptr) {
542		*((void **)ptr) = s->async->prealloc_buf;
543	}
544
545	/* XXX no reference counting */
546
547	return 0;
548}
549
550/* WARNING: not portable */
551int comedi_unmap(comedi_t * d, unsigned int subdevice)
552{
553	comedi_device *dev = (comedi_device *) d;
554	comedi_subdevice *s;
555
556	if (subdevice >= dev->n_subdevices) {
557		return -EINVAL;
558	}
559	s = dev->subdevices + subdevice;
560
561	if (!s->async)
562		return -EINVAL;
563
564	/* XXX no reference counting */
565
566	return 0;
567}
568