5 COMEDI - Linux Control and Measurement Device Interface
6 Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
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.
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.
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
21 #include "comedi_compat32.h"
23 #include <linux/module.h>
24 #include <linux/errno.h>
25 #include <linux/kernel.h>
26 #include <linux/sched.h>
27 #include <linux/fcntl.h>
28 #include <linux/delay.h>
30 #include <linux/slab.h>
31 #include <linux/kmod.h>
32 #include <linux/poll.h>
33 #include <linux/init.h>
34 #include <linux/device.h>
35 #include <linux/vmalloc.h>
37 #include "comedidev.h"
38 #include <linux/cdev.h>
39 #include <linux/stat.h>
42 #include <linux/uaccess.h>
44 #include "comedi_internal.h"
46 #define COMEDI_NUM_MINORS 0x100
47 #define COMEDI_NUM_SUBDEVICE_MINORS \
48 (COMEDI_NUM_MINORS - COMEDI_NUM_BOARD_MINORS)
50 static int comedi_num_legacy_minors;
51 module_param(comedi_num_legacy_minors, int, S_IRUGO);
52 MODULE_PARM_DESC(comedi_num_legacy_minors,
53 "number of comedi minor devices to reserve for non-auto-configured devices (default 0)"
56 unsigned int comedi_default_buf_size_kb = CONFIG_COMEDI_DEFAULT_BUF_SIZE_KB;
57 module_param(comedi_default_buf_size_kb, uint, S_IRUGO | S_IWUSR);
58 MODULE_PARM_DESC(comedi_default_buf_size_kb,
59 "default asynchronous buffer size in KiB (default "
60 __MODULE_STRING(CONFIG_COMEDI_DEFAULT_BUF_SIZE_KB) ")");
62 unsigned int comedi_default_buf_maxsize_kb
63 = CONFIG_COMEDI_DEFAULT_BUF_MAXSIZE_KB;
64 module_param(comedi_default_buf_maxsize_kb, uint, S_IRUGO | S_IWUSR);
65 MODULE_PARM_DESC(comedi_default_buf_maxsize_kb,
66 "default maximum size of asynchronous buffer in KiB (default "
67 __MODULE_STRING(CONFIG_COMEDI_DEFAULT_BUF_MAXSIZE_KB) ")");
69 static DEFINE_MUTEX(comedi_board_minor_table_lock);
70 static struct comedi_device
71 *comedi_board_minor_table[COMEDI_NUM_BOARD_MINORS];
73 static DEFINE_MUTEX(comedi_subdevice_minor_table_lock);
74 /* Note: indexed by minor - COMEDI_NUM_BOARD_MINORS. */
75 static struct comedi_subdevice
76 *comedi_subdevice_minor_table[COMEDI_NUM_SUBDEVICE_MINORS];
78 static struct class *comedi_class;
79 static struct cdev comedi_cdev;
81 static void comedi_device_init(struct comedi_device *dev)
83 kref_init(&dev->refcount);
84 spin_lock_init(&dev->spinlock);
85 mutex_init(&dev->mutex);
86 init_rwsem(&dev->attach_lock);
90 static void comedi_dev_kref_release(struct kref *kref)
92 struct comedi_device *dev =
93 container_of(kref, struct comedi_device, refcount);
95 mutex_destroy(&dev->mutex);
96 put_device(dev->class_dev);
100 int comedi_dev_put(struct comedi_device *dev)
103 return kref_put(&dev->refcount, comedi_dev_kref_release);
106 EXPORT_SYMBOL_GPL(comedi_dev_put);
108 static struct comedi_device *comedi_dev_get(struct comedi_device *dev)
111 kref_get(&dev->refcount);
115 static void comedi_device_cleanup(struct comedi_device *dev)
117 struct module *driver_module = NULL;
121 mutex_lock(&dev->mutex);
123 driver_module = dev->driver->module;
124 comedi_device_detach(dev);
125 if (driver_module && dev->use_count)
126 module_put(driver_module);
127 mutex_unlock(&dev->mutex);
130 static bool comedi_clear_board_dev(struct comedi_device *dev)
132 unsigned int i = dev->minor;
133 bool cleared = false;
135 mutex_lock(&comedi_board_minor_table_lock);
136 if (dev == comedi_board_minor_table[i]) {
137 comedi_board_minor_table[i] = NULL;
140 mutex_unlock(&comedi_board_minor_table_lock);
144 static struct comedi_device *comedi_clear_board_minor(unsigned minor)
146 struct comedi_device *dev;
148 mutex_lock(&comedi_board_minor_table_lock);
149 dev = comedi_board_minor_table[minor];
150 comedi_board_minor_table[minor] = NULL;
151 mutex_unlock(&comedi_board_minor_table_lock);
155 static void comedi_free_board_dev(struct comedi_device *dev)
158 comedi_device_cleanup(dev);
159 if (dev->class_dev) {
160 device_destroy(comedi_class,
161 MKDEV(COMEDI_MAJOR, dev->minor));
167 static struct comedi_subdevice
168 *comedi_subdevice_from_minor(const struct comedi_device *dev, unsigned minor)
170 struct comedi_subdevice *s;
171 unsigned int i = minor - COMEDI_NUM_BOARD_MINORS;
173 BUG_ON(i >= COMEDI_NUM_SUBDEVICE_MINORS);
174 mutex_lock(&comedi_subdevice_minor_table_lock);
175 s = comedi_subdevice_minor_table[i];
176 if (s && s->device != dev)
178 mutex_unlock(&comedi_subdevice_minor_table_lock);
182 static struct comedi_device *comedi_dev_get_from_board_minor(unsigned minor)
184 struct comedi_device *dev;
186 BUG_ON(minor >= COMEDI_NUM_BOARD_MINORS);
187 mutex_lock(&comedi_board_minor_table_lock);
188 dev = comedi_dev_get(comedi_board_minor_table[minor]);
189 mutex_unlock(&comedi_board_minor_table_lock);
193 static struct comedi_device *comedi_dev_get_from_subdevice_minor(unsigned minor)
195 struct comedi_device *dev;
196 struct comedi_subdevice *s;
197 unsigned int i = minor - COMEDI_NUM_BOARD_MINORS;
199 BUG_ON(i >= COMEDI_NUM_SUBDEVICE_MINORS);
200 mutex_lock(&comedi_subdevice_minor_table_lock);
201 s = comedi_subdevice_minor_table[i];
202 dev = comedi_dev_get(s ? s->device : NULL);
203 mutex_unlock(&comedi_subdevice_minor_table_lock);
207 struct comedi_device *comedi_dev_get_from_minor(unsigned minor)
209 if (minor < COMEDI_NUM_BOARD_MINORS)
210 return comedi_dev_get_from_board_minor(minor);
212 return comedi_dev_get_from_subdevice_minor(minor);
214 EXPORT_SYMBOL_GPL(comedi_dev_get_from_minor);
216 static struct comedi_subdevice *
217 comedi_read_subdevice(const struct comedi_device *dev, unsigned int minor)
219 struct comedi_subdevice *s;
221 if (minor >= COMEDI_NUM_BOARD_MINORS) {
222 s = comedi_subdevice_from_minor(dev, minor);
223 if (s == NULL || (s->subdev_flags & SDF_CMD_READ))
226 return dev->read_subdev;
229 static struct comedi_subdevice *
230 comedi_write_subdevice(const struct comedi_device *dev, unsigned int minor)
232 struct comedi_subdevice *s;
234 if (minor >= COMEDI_NUM_BOARD_MINORS) {
235 s = comedi_subdevice_from_minor(dev, minor);
236 if (s == NULL || (s->subdev_flags & SDF_CMD_WRITE))
239 return dev->write_subdev;
242 static int resize_async_buffer(struct comedi_device *dev,
243 struct comedi_subdevice *s, unsigned new_size)
245 struct comedi_async *async = s->async;
248 if (new_size > async->max_bufsize)
252 dev_dbg(dev->class_dev,
253 "subdevice is busy, cannot resize buffer\n");
256 if (comedi_buf_is_mmapped(s)) {
257 dev_dbg(dev->class_dev,
258 "subdevice is mmapped, cannot resize buffer\n");
262 /* make sure buffer is an integral number of pages
264 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK;
266 retval = comedi_buf_alloc(dev, s, new_size);
271 retval = s->buf_change(dev, s);
276 dev_dbg(dev->class_dev, "subd %d buffer resized to %i bytes\n",
277 s->index, async->prealloc_bufsz);
281 /* sysfs attribute files */
283 static ssize_t max_read_buffer_kb_show(struct device *csdev,
284 struct device_attribute *attr, char *buf)
286 unsigned int minor = MINOR(csdev->devt);
287 struct comedi_device *dev;
288 struct comedi_subdevice *s;
289 unsigned int size = 0;
291 dev = comedi_dev_get_from_minor(minor);
295 mutex_lock(&dev->mutex);
296 s = comedi_read_subdevice(dev, minor);
297 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
298 size = s->async->max_bufsize / 1024;
299 mutex_unlock(&dev->mutex);
302 return snprintf(buf, PAGE_SIZE, "%u\n", size);
305 static ssize_t max_read_buffer_kb_store(struct device *csdev,
306 struct device_attribute *attr,
307 const char *buf, size_t count)
309 unsigned int minor = MINOR(csdev->devt);
310 struct comedi_device *dev;
311 struct comedi_subdevice *s;
315 err = kstrtouint(buf, 10, &size);
318 if (size > (UINT_MAX / 1024))
322 dev = comedi_dev_get_from_minor(minor);
326 mutex_lock(&dev->mutex);
327 s = comedi_read_subdevice(dev, minor);
328 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
329 s->async->max_bufsize = size;
332 mutex_unlock(&dev->mutex);
335 return err ? err : count;
337 static DEVICE_ATTR_RW(max_read_buffer_kb);
339 static ssize_t read_buffer_kb_show(struct device *csdev,
340 struct device_attribute *attr, char *buf)
342 unsigned int minor = MINOR(csdev->devt);
343 struct comedi_device *dev;
344 struct comedi_subdevice *s;
345 unsigned int size = 0;
347 dev = comedi_dev_get_from_minor(minor);
351 mutex_lock(&dev->mutex);
352 s = comedi_read_subdevice(dev, minor);
353 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
354 size = s->async->prealloc_bufsz / 1024;
355 mutex_unlock(&dev->mutex);
358 return snprintf(buf, PAGE_SIZE, "%u\n", size);
361 static ssize_t read_buffer_kb_store(struct device *csdev,
362 struct device_attribute *attr,
363 const char *buf, size_t count)
365 unsigned int minor = MINOR(csdev->devt);
366 struct comedi_device *dev;
367 struct comedi_subdevice *s;
371 err = kstrtouint(buf, 10, &size);
374 if (size > (UINT_MAX / 1024))
378 dev = comedi_dev_get_from_minor(minor);
382 mutex_lock(&dev->mutex);
383 s = comedi_read_subdevice(dev, minor);
384 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
385 err = resize_async_buffer(dev, s, size);
388 mutex_unlock(&dev->mutex);
391 return err ? err : count;
393 static DEVICE_ATTR_RW(read_buffer_kb);
395 static ssize_t max_write_buffer_kb_show(struct device *csdev,
396 struct device_attribute *attr,
399 unsigned int minor = MINOR(csdev->devt);
400 struct comedi_device *dev;
401 struct comedi_subdevice *s;
402 unsigned int size = 0;
404 dev = comedi_dev_get_from_minor(minor);
408 mutex_lock(&dev->mutex);
409 s = comedi_write_subdevice(dev, minor);
410 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
411 size = s->async->max_bufsize / 1024;
412 mutex_unlock(&dev->mutex);
415 return snprintf(buf, PAGE_SIZE, "%u\n", size);
418 static ssize_t max_write_buffer_kb_store(struct device *csdev,
419 struct device_attribute *attr,
420 const char *buf, size_t count)
422 unsigned int minor = MINOR(csdev->devt);
423 struct comedi_device *dev;
424 struct comedi_subdevice *s;
428 err = kstrtouint(buf, 10, &size);
431 if (size > (UINT_MAX / 1024))
435 dev = comedi_dev_get_from_minor(minor);
439 mutex_lock(&dev->mutex);
440 s = comedi_write_subdevice(dev, minor);
441 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
442 s->async->max_bufsize = size;
445 mutex_unlock(&dev->mutex);
448 return err ? err : count;
450 static DEVICE_ATTR_RW(max_write_buffer_kb);
452 static ssize_t write_buffer_kb_show(struct device *csdev,
453 struct device_attribute *attr, char *buf)
455 unsigned int minor = MINOR(csdev->devt);
456 struct comedi_device *dev;
457 struct comedi_subdevice *s;
458 unsigned int size = 0;
460 dev = comedi_dev_get_from_minor(minor);
464 mutex_lock(&dev->mutex);
465 s = comedi_write_subdevice(dev, minor);
466 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
467 size = s->async->prealloc_bufsz / 1024;
468 mutex_unlock(&dev->mutex);
471 return snprintf(buf, PAGE_SIZE, "%u\n", size);
474 static ssize_t write_buffer_kb_store(struct device *csdev,
475 struct device_attribute *attr,
476 const char *buf, size_t count)
478 unsigned int minor = MINOR(csdev->devt);
479 struct comedi_device *dev;
480 struct comedi_subdevice *s;
484 err = kstrtouint(buf, 10, &size);
487 if (size > (UINT_MAX / 1024))
491 dev = comedi_dev_get_from_minor(minor);
495 mutex_lock(&dev->mutex);
496 s = comedi_write_subdevice(dev, minor);
497 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
498 err = resize_async_buffer(dev, s, size);
501 mutex_unlock(&dev->mutex);
504 return err ? err : count;
506 static DEVICE_ATTR_RW(write_buffer_kb);
508 static struct attribute *comedi_dev_attrs[] = {
509 &dev_attr_max_read_buffer_kb.attr,
510 &dev_attr_read_buffer_kb.attr,
511 &dev_attr_max_write_buffer_kb.attr,
512 &dev_attr_write_buffer_kb.attr,
515 ATTRIBUTE_GROUPS(comedi_dev);
517 static void comedi_set_subdevice_runflags(struct comedi_subdevice *s,
518 unsigned mask, unsigned bits)
522 spin_lock_irqsave(&s->spin_lock, flags);
523 s->runflags &= ~mask;
524 s->runflags |= (bits & mask);
525 spin_unlock_irqrestore(&s->spin_lock, flags);
528 static unsigned comedi_get_subdevice_runflags(struct comedi_subdevice *s)
533 spin_lock_irqsave(&s->spin_lock, flags);
534 runflags = s->runflags;
535 spin_unlock_irqrestore(&s->spin_lock, flags);
539 bool comedi_is_subdevice_running(struct comedi_subdevice *s)
541 unsigned runflags = comedi_get_subdevice_runflags(s);
543 return (runflags & SRF_RUNNING) ? true : false;
545 EXPORT_SYMBOL_GPL(comedi_is_subdevice_running);
547 static bool comedi_is_subdevice_in_error(struct comedi_subdevice *s)
549 unsigned runflags = comedi_get_subdevice_runflags(s);
551 return (runflags & SRF_ERROR) ? true : false;
554 static bool comedi_is_subdevice_idle(struct comedi_subdevice *s)
556 unsigned runflags = comedi_get_subdevice_runflags(s);
558 return (runflags & (SRF_ERROR | SRF_RUNNING)) ? false : true;
562 * comedi_alloc_spriv() - Allocate memory for the subdevice private data.
563 * @s: comedi_subdevice struct
564 * @size: size of the memory to allocate
566 * This also sets the subdevice runflags to allow the core to automatically
567 * free the private data during the detach.
569 void *comedi_alloc_spriv(struct comedi_subdevice *s, size_t size)
571 s->private = kzalloc(size, GFP_KERNEL);
573 s->runflags |= SRF_FREE_SPRIV;
576 EXPORT_SYMBOL_GPL(comedi_alloc_spriv);
579 This function restores a subdevice to an idle state.
581 static void do_become_nonbusy(struct comedi_device *dev,
582 struct comedi_subdevice *s)
584 struct comedi_async *async = s->async;
586 comedi_set_subdevice_runflags(s, SRF_RUNNING, 0);
589 async->inttrig = NULL;
590 kfree(async->cmd.chanlist);
591 async->cmd.chanlist = NULL;
593 wake_up_interruptible_all(&s->async->wait_head);
595 dev_err(dev->class_dev,
596 "BUG: (?) do_become_nonbusy called with async=NULL\n");
601 static int do_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
605 if (comedi_is_subdevice_running(s) && s->cancel)
606 ret = s->cancel(dev, s);
608 do_become_nonbusy(dev, s);
613 void comedi_device_cancel_all(struct comedi_device *dev)
615 struct comedi_subdevice *s;
621 for (i = 0; i < dev->n_subdevices; i++) {
622 s = &dev->subdevices[i];
628 static int is_device_busy(struct comedi_device *dev)
630 struct comedi_subdevice *s;
636 for (i = 0; i < dev->n_subdevices; i++) {
637 s = &dev->subdevices[i];
640 if (s->async && comedi_buf_is_mmapped(s))
652 pointer to devconfig structure
655 devconfig structure at arg
660 static int do_devconfig_ioctl(struct comedi_device *dev,
661 struct comedi_devconfig __user *arg)
663 struct comedi_devconfig it;
665 if (!capable(CAP_SYS_ADMIN))
669 if (is_device_busy(dev))
672 struct module *driver_module = dev->driver->module;
674 comedi_device_detach(dev);
675 module_put(driver_module);
680 if (copy_from_user(&it, arg, sizeof(it)))
683 it.board_name[COMEDI_NAMELEN - 1] = 0;
685 if (it.options[COMEDI_DEVCONF_AUX_DATA_LENGTH]) {
686 dev_warn(dev->class_dev,
687 "comedi_config --init_data is deprecated\n");
691 if (dev->minor >= comedi_num_legacy_minors)
692 /* don't re-use dynamically allocated comedi devices */
695 /* This increments the driver module count on success. */
696 return comedi_device_attach(dev, &it);
701 buffer configuration ioctl
704 pointer to bufconfig structure
710 modified bufconfig at arg
713 static int do_bufconfig_ioctl(struct comedi_device *dev,
714 struct comedi_bufconfig __user *arg)
716 struct comedi_bufconfig bc;
717 struct comedi_async *async;
718 struct comedi_subdevice *s;
721 if (copy_from_user(&bc, arg, sizeof(bc)))
724 if (bc.subdevice >= dev->n_subdevices)
727 s = &dev->subdevices[bc.subdevice];
731 dev_dbg(dev->class_dev,
732 "subdevice does not have async capability\n");
738 if (bc.maximum_size) {
739 if (!capable(CAP_SYS_ADMIN))
742 async->max_bufsize = bc.maximum_size;
746 retval = resize_async_buffer(dev, s, bc.size);
751 bc.size = async->prealloc_bufsz;
752 bc.maximum_size = async->max_bufsize;
755 if (copy_to_user(arg, &bc, sizeof(bc)))
766 pointer to devinfo structure
775 static int do_devinfo_ioctl(struct comedi_device *dev,
776 struct comedi_devinfo __user *arg,
779 const unsigned minor = iminor(file_inode(file));
780 struct comedi_subdevice *s;
781 struct comedi_devinfo devinfo;
783 memset(&devinfo, 0, sizeof(devinfo));
785 /* fill devinfo structure */
786 devinfo.version_code = COMEDI_VERSION_CODE;
787 devinfo.n_subdevs = dev->n_subdevices;
788 strlcpy(devinfo.driver_name, dev->driver->driver_name, COMEDI_NAMELEN);
789 strlcpy(devinfo.board_name, dev->board_name, COMEDI_NAMELEN);
791 s = comedi_read_subdevice(dev, minor);
793 devinfo.read_subdevice = s->index;
795 devinfo.read_subdevice = -1;
797 s = comedi_write_subdevice(dev, minor);
799 devinfo.write_subdevice = s->index;
801 devinfo.write_subdevice = -1;
803 if (copy_to_user(arg, &devinfo, sizeof(devinfo)))
814 pointer to array of subdevice info structures
820 array of subdevice info structures at arg
823 static int do_subdinfo_ioctl(struct comedi_device *dev,
824 struct comedi_subdinfo __user *arg, void *file)
827 struct comedi_subdinfo *tmp, *us;
828 struct comedi_subdevice *s;
830 tmp = kcalloc(dev->n_subdevices, sizeof(*tmp), GFP_KERNEL);
834 /* fill subdinfo structs */
835 for (i = 0; i < dev->n_subdevices; i++) {
836 s = &dev->subdevices[i];
840 us->n_chan = s->n_chan;
841 us->subd_flags = s->subdev_flags;
842 if (comedi_is_subdevice_running(s))
843 us->subd_flags |= SDF_RUNNING;
844 #define TIMER_nanosec 5 /* backwards compatibility */
845 us->timer_type = TIMER_nanosec;
846 us->len_chanlist = s->len_chanlist;
847 us->maxdata = s->maxdata;
848 if (s->range_table) {
850 (i << 24) | (0 << 16) | (s->range_table->length);
852 us->range_type = 0; /* XXX */
856 us->subd_flags |= SDF_BUSY;
858 us->subd_flags |= SDF_BUSY_OWNER;
860 us->subd_flags |= SDF_LOCKED;
862 us->subd_flags |= SDF_LOCK_OWNER;
863 if (!s->maxdata && s->maxdata_list)
864 us->subd_flags |= SDF_MAXDATA;
865 if (s->range_table_list)
866 us->subd_flags |= SDF_RANGETYPE;
868 us->subd_flags |= SDF_CMD;
870 if (s->insn_bits != &insn_inval)
871 us->insn_bits_support = COMEDI_SUPPORTED;
873 us->insn_bits_support = COMEDI_UNSUPPORTED;
876 ret = copy_to_user(arg, tmp, dev->n_subdevices * sizeof(*tmp));
880 return ret ? -EFAULT : 0;
888 pointer to chaninfo structure
891 chaninfo structure at arg
894 arrays at elements of chaninfo structure
897 static int do_chaninfo_ioctl(struct comedi_device *dev,
898 struct comedi_chaninfo __user *arg)
900 struct comedi_subdevice *s;
901 struct comedi_chaninfo it;
903 if (copy_from_user(&it, arg, sizeof(it)))
906 if (it.subdev >= dev->n_subdevices)
908 s = &dev->subdevices[it.subdev];
910 if (it.maxdata_list) {
911 if (s->maxdata || !s->maxdata_list)
913 if (copy_to_user(it.maxdata_list, s->maxdata_list,
914 s->n_chan * sizeof(unsigned int)))
919 return -EINVAL; /* flaglist not supported */
924 if (!s->range_table_list)
926 for (i = 0; i < s->n_chan; i++) {
929 x = (dev->minor << 28) | (it.subdev << 24) | (i << 16) |
930 (s->range_table_list[i]->length);
931 if (put_user(x, it.rangelist + i))
935 if (copy_to_user(it.rangelist, s->range_type_list,
936 s->n_chan * sizeof(unsigned int)))
946 buffer information ioctl
949 pointer to bufinfo structure
955 modified bufinfo at arg
958 static int do_bufinfo_ioctl(struct comedi_device *dev,
959 struct comedi_bufinfo __user *arg, void *file)
961 struct comedi_bufinfo bi;
962 struct comedi_subdevice *s;
963 struct comedi_async *async;
965 if (copy_from_user(&bi, arg, sizeof(bi)))
968 if (bi.subdevice >= dev->n_subdevices)
971 s = &dev->subdevices[bi.subdevice];
976 dev_dbg(dev->class_dev,
977 "subdevice does not have async capability\n");
978 bi.buf_write_ptr = 0;
980 bi.buf_write_count = 0;
981 bi.buf_read_count = 0;
983 bi.bytes_written = 0;
988 bi.bytes_written = 0;
989 goto copyback_position;
994 if (bi.bytes_read && (s->subdev_flags & SDF_CMD_READ)) {
995 bi.bytes_read = comedi_buf_read_alloc(s, bi.bytes_read);
996 comedi_buf_read_free(s, bi.bytes_read);
998 if (comedi_is_subdevice_idle(s) &&
999 comedi_buf_n_bytes_ready(s) == 0) {
1000 do_become_nonbusy(dev, s);
1004 if (bi.bytes_written && (s->subdev_flags & SDF_CMD_WRITE)) {
1006 comedi_buf_write_alloc(s, bi.bytes_written);
1007 comedi_buf_write_free(s, bi.bytes_written);
1011 bi.buf_write_count = async->buf_write_count;
1012 bi.buf_write_ptr = async->buf_write_ptr;
1013 bi.buf_read_count = async->buf_read_count;
1014 bi.buf_read_ptr = async->buf_read_ptr;
1017 if (copy_to_user(arg, &bi, sizeof(bi)))
1023 static int check_insn_config_length(struct comedi_insn *insn,
1030 case INSN_CONFIG_DIO_OUTPUT:
1031 case INSN_CONFIG_DIO_INPUT:
1032 case INSN_CONFIG_DISARM:
1033 case INSN_CONFIG_RESET:
1037 case INSN_CONFIG_ARM:
1038 case INSN_CONFIG_DIO_QUERY:
1039 case INSN_CONFIG_BLOCK_SIZE:
1040 case INSN_CONFIG_FILTER:
1041 case INSN_CONFIG_SERIAL_CLOCK:
1042 case INSN_CONFIG_BIDIRECTIONAL_DATA:
1043 case INSN_CONFIG_ALT_SOURCE:
1044 case INSN_CONFIG_SET_COUNTER_MODE:
1045 case INSN_CONFIG_8254_READ_STATUS:
1046 case INSN_CONFIG_SET_ROUTING:
1047 case INSN_CONFIG_GET_ROUTING:
1048 case INSN_CONFIG_GET_PWM_STATUS:
1049 case INSN_CONFIG_PWM_SET_PERIOD:
1050 case INSN_CONFIG_PWM_GET_PERIOD:
1054 case INSN_CONFIG_SET_GATE_SRC:
1055 case INSN_CONFIG_GET_GATE_SRC:
1056 case INSN_CONFIG_SET_CLOCK_SRC:
1057 case INSN_CONFIG_GET_CLOCK_SRC:
1058 case INSN_CONFIG_SET_OTHER_SRC:
1059 case INSN_CONFIG_GET_COUNTER_STATUS:
1060 case INSN_CONFIG_PWM_SET_H_BRIDGE:
1061 case INSN_CONFIG_PWM_GET_H_BRIDGE:
1062 case INSN_CONFIG_GET_HARDWARE_BUFFER_SIZE:
1066 case INSN_CONFIG_PWM_OUTPUT:
1067 case INSN_CONFIG_ANALOG_TRIG:
1071 case INSN_CONFIG_DIGITAL_TRIG:
1075 /* by default we allow the insn since we don't have checks for
1076 * all possible cases yet */
1078 pr_warn("No check for data length of config insn id %i is implemented\n",
1080 pr_warn("Add a check to %s in %s\n", __func__, __FILE__);
1081 pr_warn("Assuming n=%i is correct\n", insn->n);
1087 static int parse_insn(struct comedi_device *dev, struct comedi_insn *insn,
1088 unsigned int *data, void *file)
1090 struct comedi_subdevice *s;
1094 if (insn->insn & INSN_MASK_SPECIAL) {
1095 /* a non-subdevice instruction */
1097 switch (insn->insn) {
1107 do_gettimeofday(&tv);
1108 data[0] = tv.tv_sec;
1109 data[1] = tv.tv_usec;
1115 if (insn->n != 1 || data[0] >= 100000) {
1119 udelay(data[0] / 1000);
1127 if (insn->subdev >= dev->n_subdevices) {
1128 dev_dbg(dev->class_dev,
1129 "%d not usable subdevice\n",
1134 s = &dev->subdevices[insn->subdev];
1136 dev_dbg(dev->class_dev, "no async\n");
1140 if (!s->async->inttrig) {
1141 dev_dbg(dev->class_dev, "no inttrig\n");
1145 ret = s->async->inttrig(dev, s, data[0]);
1150 dev_dbg(dev->class_dev, "invalid insn\n");
1155 /* a subdevice instruction */
1156 unsigned int maxdata;
1158 if (insn->subdev >= dev->n_subdevices) {
1159 dev_dbg(dev->class_dev, "subdevice %d out of range\n",
1164 s = &dev->subdevices[insn->subdev];
1166 if (s->type == COMEDI_SUBD_UNUSED) {
1167 dev_dbg(dev->class_dev, "%d not usable subdevice\n",
1173 /* are we locked? (ioctl lock) */
1174 if (s->lock && s->lock != file) {
1175 dev_dbg(dev->class_dev, "device locked\n");
1180 ret = comedi_check_chanlist(s, 1, &insn->chanspec);
1183 dev_dbg(dev->class_dev, "bad chanspec\n");
1191 /* This looks arbitrary. It is. */
1192 s->busy = &parse_insn;
1193 switch (insn->insn) {
1195 ret = s->insn_read(dev, s, insn, data);
1196 if (ret == -ETIMEDOUT) {
1197 dev_dbg(dev->class_dev,
1198 "subdevice %d read instruction timed out\n",
1203 maxdata = s->maxdata_list
1204 ? s->maxdata_list[CR_CHAN(insn->chanspec)]
1206 for (i = 0; i < insn->n; ++i) {
1207 if (data[i] > maxdata) {
1209 dev_dbg(dev->class_dev,
1210 "bad data value(s)\n");
1215 ret = s->insn_write(dev, s, insn, data);
1216 if (ret == -ETIMEDOUT) {
1217 dev_dbg(dev->class_dev,
1218 "subdevice %d write instruction timed out\n",
1227 /* Most drivers ignore the base channel in
1228 * insn->chanspec. Fix this here if
1229 * the subdevice has <= 32 channels. */
1230 unsigned int orig_mask = data[0];
1231 unsigned int shift = 0;
1233 if (s->n_chan <= 32) {
1234 shift = CR_CHAN(insn->chanspec);
1241 ret = s->insn_bits(dev, s, insn, data);
1242 data[0] = orig_mask;
1248 ret = check_insn_config_length(insn, data);
1251 ret = s->insn_config(dev, s, insn, data);
1267 * synchronous instructions
1270 * pointer to sync cmd structure
1273 * sync cmd struct at arg
1280 /* arbitrary limits */
1281 #define MAX_SAMPLES 256
1282 static int do_insnlist_ioctl(struct comedi_device *dev,
1283 struct comedi_insnlist __user *arg, void *file)
1285 struct comedi_insnlist insnlist;
1286 struct comedi_insn *insns = NULL;
1287 unsigned int *data = NULL;
1291 if (copy_from_user(&insnlist, arg, sizeof(insnlist)))
1294 data = kmalloc_array(MAX_SAMPLES, sizeof(unsigned int), GFP_KERNEL);
1300 insns = kcalloc(insnlist.n_insns, sizeof(*insns), GFP_KERNEL);
1306 if (copy_from_user(insns, insnlist.insns,
1307 sizeof(*insns) * insnlist.n_insns)) {
1308 dev_dbg(dev->class_dev, "copy_from_user failed\n");
1313 for (i = 0; i < insnlist.n_insns; i++) {
1314 if (insns[i].n > MAX_SAMPLES) {
1315 dev_dbg(dev->class_dev,
1316 "number of samples too large\n");
1320 if (insns[i].insn & INSN_MASK_WRITE) {
1321 if (copy_from_user(data, insns[i].data,
1322 insns[i].n * sizeof(unsigned int))) {
1323 dev_dbg(dev->class_dev,
1324 "copy_from_user failed\n");
1329 ret = parse_insn(dev, insns + i, data, file);
1332 if (insns[i].insn & INSN_MASK_READ) {
1333 if (copy_to_user(insns[i].data, data,
1334 insns[i].n * sizeof(unsigned int))) {
1335 dev_dbg(dev->class_dev,
1336 "copy_to_user failed\n");
1356 * synchronous instructions
1362 * struct comedi_insn struct at arg
1368 static int do_insn_ioctl(struct comedi_device *dev,
1369 struct comedi_insn __user *arg, void *file)
1371 struct comedi_insn insn;
1372 unsigned int *data = NULL;
1375 data = kmalloc_array(MAX_SAMPLES, sizeof(unsigned int), GFP_KERNEL);
1381 if (copy_from_user(&insn, arg, sizeof(insn))) {
1386 /* This is where the behavior of insn and insnlist deviate. */
1387 if (insn.n > MAX_SAMPLES)
1388 insn.n = MAX_SAMPLES;
1389 if (insn.insn & INSN_MASK_WRITE) {
1390 if (copy_from_user(data,
1392 insn.n * sizeof(unsigned int))) {
1397 ret = parse_insn(dev, &insn, data, file);
1400 if (insn.insn & INSN_MASK_READ) {
1401 if (copy_to_user(insn.data,
1403 insn.n * sizeof(unsigned int))) {
1416 static int __comedi_get_user_cmd(struct comedi_device *dev,
1417 struct comedi_cmd __user *arg,
1418 struct comedi_cmd *cmd)
1420 struct comedi_subdevice *s;
1422 if (copy_from_user(cmd, arg, sizeof(*cmd))) {
1423 dev_dbg(dev->class_dev, "bad cmd address\n");
1427 if (cmd->subdev >= dev->n_subdevices) {
1428 dev_dbg(dev->class_dev, "%d no such subdevice\n", cmd->subdev);
1432 s = &dev->subdevices[cmd->subdev];
1434 if (s->type == COMEDI_SUBD_UNUSED) {
1435 dev_dbg(dev->class_dev, "%d not valid subdevice\n",
1440 if (!s->do_cmd || !s->do_cmdtest || !s->async) {
1441 dev_dbg(dev->class_dev,
1442 "subdevice %d does not support commands\n",
1447 /* make sure channel/gain list isn't too long */
1448 if (cmd->chanlist_len > s->len_chanlist) {
1449 dev_dbg(dev->class_dev, "channel/gain list too long %d > %d\n",
1450 cmd->chanlist_len, s->len_chanlist);
1457 static int __comedi_get_user_chanlist(struct comedi_device *dev,
1458 struct comedi_subdevice *s,
1459 unsigned int __user *user_chanlist,
1460 struct comedi_cmd *cmd)
1462 unsigned int *chanlist;
1465 cmd->chanlist = NULL;
1466 chanlist = memdup_user(user_chanlist,
1467 cmd->chanlist_len * sizeof(unsigned int));
1468 if (IS_ERR(chanlist))
1469 return PTR_ERR(chanlist);
1471 /* make sure each element in channel/gain list is valid */
1472 ret = comedi_check_chanlist(s, cmd->chanlist_len, chanlist);
1478 cmd->chanlist = chanlist;
1483 static int do_cmd_ioctl(struct comedi_device *dev,
1484 struct comedi_cmd __user *arg, void *file)
1486 struct comedi_cmd cmd;
1487 struct comedi_subdevice *s;
1488 struct comedi_async *async;
1489 unsigned int __user *user_chanlist;
1492 /* get the user's cmd and do some simple validation */
1493 ret = __comedi_get_user_cmd(dev, arg, &cmd);
1497 /* save user's chanlist pointer so it can be restored later */
1498 user_chanlist = (unsigned int __user *)cmd.chanlist;
1500 s = &dev->subdevices[cmd.subdev];
1503 /* are we locked? (ioctl lock) */
1504 if (s->lock && s->lock != file) {
1505 dev_dbg(dev->class_dev, "subdevice locked\n");
1511 dev_dbg(dev->class_dev, "subdevice busy\n");
1515 /* make sure channel/gain list isn't too short */
1516 if (cmd.chanlist_len < 1) {
1517 dev_dbg(dev->class_dev, "channel/gain list too short %u < 1\n",
1523 async->cmd.data = NULL;
1525 /* load channel/gain list */
1526 ret = __comedi_get_user_chanlist(dev, s, user_chanlist, &async->cmd);
1530 ret = s->do_cmdtest(dev, s, &async->cmd);
1532 if (async->cmd.flags & CMDF_BOGUS || ret) {
1533 dev_dbg(dev->class_dev, "test returned %d\n", ret);
1535 /* restore chanlist pointer before copying back */
1536 cmd.chanlist = (unsigned int __force *)user_chanlist;
1538 if (copy_to_user(arg, &cmd, sizeof(cmd))) {
1539 dev_dbg(dev->class_dev, "fault writing cmd\n");
1547 if (!async->prealloc_bufsz) {
1549 dev_dbg(dev->class_dev, "no buffer (?)\n");
1553 comedi_buf_reset(s);
1556 COMEDI_CB_EOA | COMEDI_CB_BLOCK | COMEDI_CB_ERROR |
1558 if (async->cmd.flags & CMDF_WAKE_EOS)
1559 async->cb_mask |= COMEDI_CB_EOS;
1561 comedi_set_subdevice_runflags(s, SRF_ERROR | SRF_RUNNING, SRF_RUNNING);
1563 /* set s->busy _after_ setting SRF_RUNNING flag to avoid race with
1564 * comedi_read() or comedi_write() */
1566 ret = s->do_cmd(dev, s);
1571 do_become_nonbusy(dev, s);
1578 command testing ioctl
1581 pointer to cmd structure
1584 cmd structure at arg
1588 modified cmd structure at arg
1591 static int do_cmdtest_ioctl(struct comedi_device *dev,
1592 struct comedi_cmd __user *arg, void *file)
1594 struct comedi_cmd cmd;
1595 struct comedi_subdevice *s;
1596 unsigned int __user *user_chanlist;
1599 /* get the user's cmd and do some simple validation */
1600 ret = __comedi_get_user_cmd(dev, arg, &cmd);
1604 /* save user's chanlist pointer so it can be restored later */
1605 user_chanlist = (unsigned int __user *)cmd.chanlist;
1607 s = &dev->subdevices[cmd.subdev];
1609 /* user_chanlist can be NULL for COMEDI_CMDTEST ioctl */
1610 if (user_chanlist) {
1611 /* load channel/gain list */
1612 ret = __comedi_get_user_chanlist(dev, s, user_chanlist, &cmd);
1617 ret = s->do_cmdtest(dev, s, &cmd);
1619 kfree(cmd.chanlist); /* free kernel copy of user chanlist */
1621 /* restore chanlist pointer before copying back */
1622 cmd.chanlist = (unsigned int __force *)user_chanlist;
1624 if (copy_to_user(arg, &cmd, sizeof(cmd))) {
1625 dev_dbg(dev->class_dev, "bad cmd address\n");
1647 static int do_lock_ioctl(struct comedi_device *dev, unsigned long arg,
1651 unsigned long flags;
1652 struct comedi_subdevice *s;
1654 if (arg >= dev->n_subdevices)
1656 s = &dev->subdevices[arg];
1658 spin_lock_irqsave(&s->spin_lock, flags);
1659 if (s->busy || s->lock)
1663 spin_unlock_irqrestore(&s->spin_lock, flags);
1681 This function isn't protected by the semaphore, since
1682 we already own the lock.
1684 static int do_unlock_ioctl(struct comedi_device *dev, unsigned long arg,
1687 struct comedi_subdevice *s;
1689 if (arg >= dev->n_subdevices)
1691 s = &dev->subdevices[arg];
1696 if (s->lock && s->lock != file)
1699 if (s->lock == file)
1707 cancel acquisition ioctl
1719 static int do_cancel_ioctl(struct comedi_device *dev, unsigned long arg,
1722 struct comedi_subdevice *s;
1725 if (arg >= dev->n_subdevices)
1727 s = &dev->subdevices[arg];
1728 if (s->async == NULL)
1734 if (s->busy != file)
1737 ret = do_cancel(dev, s);
1744 instructs driver to synchronize buffers
1756 static int do_poll_ioctl(struct comedi_device *dev, unsigned long arg,
1759 struct comedi_subdevice *s;
1761 if (arg >= dev->n_subdevices)
1763 s = &dev->subdevices[arg];
1768 if (s->busy != file)
1772 return s->poll(dev, s);
1777 static long comedi_unlocked_ioctl(struct file *file, unsigned int cmd,
1780 const unsigned minor = iminor(file_inode(file));
1781 struct comedi_device *dev = file->private_data;
1784 mutex_lock(&dev->mutex);
1786 /* Device config is special, because it must work on
1787 * an unconfigured device. */
1788 if (cmd == COMEDI_DEVCONFIG) {
1789 if (minor >= COMEDI_NUM_BOARD_MINORS) {
1790 /* Device config not appropriate on non-board minors. */
1794 rc = do_devconfig_ioctl(dev,
1795 (struct comedi_devconfig __user *)arg);
1798 dev->minor >= comedi_num_legacy_minors) {
1799 /* Successfully unconfigured a dynamically
1800 * allocated device. Try and remove it. */
1801 if (comedi_clear_board_dev(dev)) {
1802 mutex_unlock(&dev->mutex);
1803 comedi_free_board_dev(dev);
1811 if (!dev->attached) {
1812 dev_dbg(dev->class_dev, "no driver attached\n");
1818 case COMEDI_BUFCONFIG:
1819 rc = do_bufconfig_ioctl(dev,
1820 (struct comedi_bufconfig __user *)arg);
1822 case COMEDI_DEVINFO:
1823 rc = do_devinfo_ioctl(dev, (struct comedi_devinfo __user *)arg,
1826 case COMEDI_SUBDINFO:
1827 rc = do_subdinfo_ioctl(dev,
1828 (struct comedi_subdinfo __user *)arg,
1831 case COMEDI_CHANINFO:
1832 rc = do_chaninfo_ioctl(dev, (void __user *)arg);
1834 case COMEDI_RANGEINFO:
1835 rc = do_rangeinfo_ioctl(dev, (void __user *)arg);
1837 case COMEDI_BUFINFO:
1838 rc = do_bufinfo_ioctl(dev,
1839 (struct comedi_bufinfo __user *)arg,
1843 rc = do_lock_ioctl(dev, arg, file);
1846 rc = do_unlock_ioctl(dev, arg, file);
1849 rc = do_cancel_ioctl(dev, arg, file);
1852 rc = do_cmd_ioctl(dev, (struct comedi_cmd __user *)arg, file);
1854 case COMEDI_CMDTEST:
1855 rc = do_cmdtest_ioctl(dev, (struct comedi_cmd __user *)arg,
1858 case COMEDI_INSNLIST:
1859 rc = do_insnlist_ioctl(dev,
1860 (struct comedi_insnlist __user *)arg,
1864 rc = do_insn_ioctl(dev, (struct comedi_insn __user *)arg,
1868 rc = do_poll_ioctl(dev, arg, file);
1876 mutex_unlock(&dev->mutex);
1880 static void comedi_vm_open(struct vm_area_struct *area)
1882 struct comedi_buf_map *bm;
1884 bm = area->vm_private_data;
1885 comedi_buf_map_get(bm);
1888 static void comedi_vm_close(struct vm_area_struct *area)
1890 struct comedi_buf_map *bm;
1892 bm = area->vm_private_data;
1893 comedi_buf_map_put(bm);
1896 static struct vm_operations_struct comedi_vm_ops = {
1897 .open = comedi_vm_open,
1898 .close = comedi_vm_close,
1901 static int comedi_mmap(struct file *file, struct vm_area_struct *vma)
1903 const unsigned minor = iminor(file_inode(file));
1904 struct comedi_device *dev = file->private_data;
1905 struct comedi_subdevice *s;
1906 struct comedi_async *async;
1907 struct comedi_buf_map *bm = NULL;
1908 unsigned long start = vma->vm_start;
1915 * 'trylock' avoids circular dependency with current->mm->mmap_sem
1916 * and down-reading &dev->attach_lock should normally succeed without
1917 * contention unless the device is in the process of being attached
1920 if (!down_read_trylock(&dev->attach_lock))
1923 if (!dev->attached) {
1924 dev_dbg(dev->class_dev, "no driver attached\n");
1929 if (vma->vm_flags & VM_WRITE)
1930 s = comedi_write_subdevice(dev, minor);
1932 s = comedi_read_subdevice(dev, minor);
1944 if (vma->vm_pgoff != 0) {
1945 dev_dbg(dev->class_dev, "mmap() offset must be 0.\n");
1950 size = vma->vm_end - vma->vm_start;
1951 if (size > async->prealloc_bufsz) {
1955 if (size & (~PAGE_MASK)) {
1960 n_pages = size >> PAGE_SHIFT;
1962 /* get reference to current buf map (if any) */
1963 bm = comedi_buf_map_from_subdev_get(s);
1964 if (!bm || n_pages > bm->n_pages) {
1968 for (i = 0; i < n_pages; ++i) {
1969 struct comedi_buf_page *buf = &bm->page_list[i];
1971 if (remap_pfn_range(vma, start,
1972 page_to_pfn(virt_to_page(buf->virt_addr)),
1973 PAGE_SIZE, PAGE_SHARED)) {
1980 vma->vm_ops = &comedi_vm_ops;
1981 vma->vm_private_data = bm;
1983 vma->vm_ops->open(vma);
1987 up_read(&dev->attach_lock);
1988 comedi_buf_map_put(bm); /* put reference to buf map - okay if NULL */
1992 static unsigned int comedi_poll(struct file *file, poll_table *wait)
1994 unsigned int mask = 0;
1995 const unsigned minor = iminor(file_inode(file));
1996 struct comedi_device *dev = file->private_data;
1997 struct comedi_subdevice *s;
1999 mutex_lock(&dev->mutex);
2001 if (!dev->attached) {
2002 dev_dbg(dev->class_dev, "no driver attached\n");
2006 s = comedi_read_subdevice(dev, minor);
2007 if (s && s->async) {
2008 poll_wait(file, &s->async->wait_head, wait);
2009 if (!s->busy || !comedi_is_subdevice_running(s) ||
2010 comedi_buf_read_n_available(s) > 0)
2011 mask |= POLLIN | POLLRDNORM;
2014 s = comedi_write_subdevice(dev, minor);
2015 if (s && s->async) {
2016 unsigned int bps = bytes_per_sample(s);
2018 poll_wait(file, &s->async->wait_head, wait);
2019 comedi_buf_write_alloc(s, s->async->prealloc_bufsz);
2020 if (!s->busy || !comedi_is_subdevice_running(s) ||
2021 comedi_buf_write_n_allocated(s) >= bps)
2022 mask |= POLLOUT | POLLWRNORM;
2026 mutex_unlock(&dev->mutex);
2030 static ssize_t comedi_write(struct file *file, const char __user *buf,
2031 size_t nbytes, loff_t *offset)
2033 struct comedi_subdevice *s;
2034 struct comedi_async *async;
2035 int n, m, count = 0, retval = 0;
2036 DECLARE_WAITQUEUE(wait, current);
2037 const unsigned minor = iminor(file_inode(file));
2038 struct comedi_device *dev = file->private_data;
2039 bool on_wait_queue = false;
2041 unsigned int old_detach_count;
2043 /* Protect against device detachment during operation. */
2044 down_read(&dev->attach_lock);
2045 attach_locked = true;
2046 old_detach_count = dev->detach_count;
2048 if (!dev->attached) {
2049 dev_dbg(dev->class_dev, "no driver attached\n");
2054 s = comedi_write_subdevice(dev, minor);
2055 if (!s || !s->async) {
2062 if (!s->busy || !nbytes)
2064 if (s->busy != file) {
2069 add_wait_queue(&async->wait_head, &wait);
2070 on_wait_queue = true;
2071 while (nbytes > 0 && !retval) {
2072 set_current_state(TASK_INTERRUPTIBLE);
2074 if (!comedi_is_subdevice_running(s)) {
2076 struct comedi_subdevice *new_s;
2078 if (comedi_is_subdevice_in_error(s))
2083 * To avoid deadlock, cannot acquire dev->mutex
2084 * while dev->attach_lock is held. Need to
2085 * remove task from the async wait queue before
2086 * releasing dev->attach_lock, as it might not
2087 * be valid afterwards.
2089 remove_wait_queue(&async->wait_head, &wait);
2090 on_wait_queue = false;
2091 up_read(&dev->attach_lock);
2092 attach_locked = false;
2093 mutex_lock(&dev->mutex);
2095 * Become non-busy unless things have changed
2096 * behind our back. Checking dev->detach_count
2097 * is unchanged ought to be sufficient (unless
2098 * there have been 2**32 detaches in the
2099 * meantime!), but check the subdevice pointer
2100 * as well just in case.
2102 new_s = comedi_write_subdevice(dev, minor);
2103 if (dev->attached &&
2104 old_detach_count == dev->detach_count &&
2105 s == new_s && new_s->async == async)
2106 do_become_nonbusy(dev, s);
2107 mutex_unlock(&dev->mutex);
2115 if (async->buf_write_ptr + m > async->prealloc_bufsz)
2116 m = async->prealloc_bufsz - async->buf_write_ptr;
2117 comedi_buf_write_alloc(s, async->prealloc_bufsz);
2118 if (m > comedi_buf_write_n_allocated(s))
2119 m = comedi_buf_write_n_allocated(s);
2124 if (file->f_flags & O_NONBLOCK) {
2129 if (signal_pending(current)) {
2130 retval = -ERESTARTSYS;
2135 if (s->busy != file) {
2142 m = copy_from_user(async->prealloc_buf + async->buf_write_ptr,
2148 comedi_buf_write_free(s, n);
2154 break; /* makes device work like a pipe */
2158 remove_wait_queue(&async->wait_head, &wait);
2159 set_current_state(TASK_RUNNING);
2161 up_read(&dev->attach_lock);
2163 return count ? count : retval;
2166 static ssize_t comedi_read(struct file *file, char __user *buf, size_t nbytes,
2169 struct comedi_subdevice *s;
2170 struct comedi_async *async;
2171 int n, m, count = 0, retval = 0;
2172 DECLARE_WAITQUEUE(wait, current);
2173 const unsigned minor = iminor(file_inode(file));
2174 struct comedi_device *dev = file->private_data;
2175 unsigned int old_detach_count;
2176 bool become_nonbusy = false;
2179 /* Protect against device detachment during operation. */
2180 down_read(&dev->attach_lock);
2181 attach_locked = true;
2182 old_detach_count = dev->detach_count;
2184 if (!dev->attached) {
2185 dev_dbg(dev->class_dev, "no driver attached\n");
2190 s = comedi_read_subdevice(dev, minor);
2191 if (!s || !s->async) {
2197 if (!s->busy || !nbytes)
2199 if (s->busy != file) {
2204 add_wait_queue(&async->wait_head, &wait);
2205 while (nbytes > 0 && !retval) {
2206 set_current_state(TASK_INTERRUPTIBLE);
2210 m = comedi_buf_read_n_available(s);
2211 if (async->buf_read_ptr + m > async->prealloc_bufsz)
2212 m = async->prealloc_bufsz - async->buf_read_ptr;
2217 if (!comedi_is_subdevice_running(s)) {
2218 if (comedi_is_subdevice_in_error(s))
2222 become_nonbusy = true;
2225 if (file->f_flags & O_NONBLOCK) {
2230 if (signal_pending(current)) {
2231 retval = -ERESTARTSYS;
2238 if (s->busy != file) {
2244 m = copy_to_user(buf, async->prealloc_buf +
2245 async->buf_read_ptr, n);
2251 comedi_buf_read_alloc(s, n);
2252 comedi_buf_read_free(s, n);
2258 break; /* makes device work like a pipe */
2260 remove_wait_queue(&async->wait_head, &wait);
2261 set_current_state(TASK_RUNNING);
2262 if (become_nonbusy || comedi_is_subdevice_idle(s)) {
2263 struct comedi_subdevice *new_s;
2266 * To avoid deadlock, cannot acquire dev->mutex
2267 * while dev->attach_lock is held.
2269 up_read(&dev->attach_lock);
2270 attach_locked = false;
2271 mutex_lock(&dev->mutex);
2273 * Check device hasn't become detached behind our back.
2274 * Checking dev->detach_count is unchanged ought to be
2275 * sufficient (unless there have been 2**32 detaches in the
2276 * meantime!), but check the subdevice pointer as well just in
2279 new_s = comedi_read_subdevice(dev, minor);
2280 if (dev->attached && old_detach_count == dev->detach_count &&
2281 s == new_s && new_s->async == async) {
2282 if (become_nonbusy || comedi_buf_n_bytes_ready(s) == 0)
2283 do_become_nonbusy(dev, s);
2285 mutex_unlock(&dev->mutex);
2289 up_read(&dev->attach_lock);
2291 return count ? count : retval;
2294 static int comedi_open(struct inode *inode, struct file *file)
2296 const unsigned minor = iminor(inode);
2297 struct comedi_device *dev = comedi_dev_get_from_minor(minor);
2301 pr_debug("invalid minor number\n");
2305 mutex_lock(&dev->mutex);
2306 if (!dev->attached && !capable(CAP_NET_ADMIN)) {
2307 dev_dbg(dev->class_dev, "not attached and not CAP_NET_ADMIN\n");
2311 if (dev->attached && dev->use_count == 0) {
2312 if (!try_module_get(dev->driver->module)) {
2317 rc = dev->open(dev);
2319 module_put(dev->driver->module);
2326 file->private_data = dev;
2330 mutex_unlock(&dev->mutex);
2332 comedi_dev_put(dev);
2336 static int comedi_fasync(int fd, struct file *file, int on)
2338 struct comedi_device *dev = file->private_data;
2340 return fasync_helper(fd, file, on, &dev->async_queue);
2343 static int comedi_close(struct inode *inode, struct file *file)
2345 struct comedi_device *dev = file->private_data;
2346 struct comedi_subdevice *s = NULL;
2349 mutex_lock(&dev->mutex);
2351 if (dev->subdevices) {
2352 for (i = 0; i < dev->n_subdevices; i++) {
2353 s = &dev->subdevices[i];
2355 if (s->busy == file)
2357 if (s->lock == file)
2361 if (dev->attached && dev->use_count == 1) {
2364 module_put(dev->driver->module);
2369 mutex_unlock(&dev->mutex);
2370 comedi_dev_put(dev);
2375 static const struct file_operations comedi_fops = {
2376 .owner = THIS_MODULE,
2377 .unlocked_ioctl = comedi_unlocked_ioctl,
2378 .compat_ioctl = comedi_compat_ioctl,
2379 .open = comedi_open,
2380 .release = comedi_close,
2381 .read = comedi_read,
2382 .write = comedi_write,
2383 .mmap = comedi_mmap,
2384 .poll = comedi_poll,
2385 .fasync = comedi_fasync,
2386 .llseek = noop_llseek,
2389 void comedi_event(struct comedi_device *dev, struct comedi_subdevice *s)
2391 struct comedi_async *async = s->async;
2392 unsigned runflags = 0;
2393 unsigned runflags_mask = 0;
2395 if (!comedi_is_subdevice_running(s))
2399 async->events & (COMEDI_CB_EOA | COMEDI_CB_ERROR |
2400 COMEDI_CB_OVERFLOW)) {
2401 runflags_mask |= SRF_RUNNING;
2403 /* remember if an error event has occurred, so an error
2404 * can be returned the next time the user does a read() */
2405 if (s->async->events & (COMEDI_CB_ERROR | COMEDI_CB_OVERFLOW)) {
2406 runflags_mask |= SRF_ERROR;
2407 runflags |= SRF_ERROR;
2409 if (runflags_mask) {
2410 /*sets SRF_ERROR and SRF_RUNNING together atomically */
2411 comedi_set_subdevice_runflags(s, runflags_mask, runflags);
2414 if (async->cb_mask & s->async->events) {
2415 wake_up_interruptible(&async->wait_head);
2416 if (s->subdev_flags & SDF_CMD_READ)
2417 kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
2418 if (s->subdev_flags & SDF_CMD_WRITE)
2419 kill_fasync(&dev->async_queue, SIGIO, POLL_OUT);
2421 s->async->events = 0;
2423 EXPORT_SYMBOL_GPL(comedi_event);
2425 /* Note: the ->mutex is pre-locked on successful return */
2426 struct comedi_device *comedi_alloc_board_minor(struct device *hardware_device)
2428 struct comedi_device *dev;
2429 struct device *csdev;
2432 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
2434 return ERR_PTR(-ENOMEM);
2435 comedi_device_init(dev);
2436 comedi_set_hw_dev(dev, hardware_device);
2437 mutex_lock(&dev->mutex);
2438 mutex_lock(&comedi_board_minor_table_lock);
2439 for (i = hardware_device ? comedi_num_legacy_minors : 0;
2440 i < COMEDI_NUM_BOARD_MINORS; ++i) {
2441 if (comedi_board_minor_table[i] == NULL) {
2442 comedi_board_minor_table[i] = dev;
2446 mutex_unlock(&comedi_board_minor_table_lock);
2447 if (i == COMEDI_NUM_BOARD_MINORS) {
2448 mutex_unlock(&dev->mutex);
2449 comedi_device_cleanup(dev);
2450 comedi_dev_put(dev);
2451 pr_err("ran out of minor numbers for board device files\n");
2452 return ERR_PTR(-EBUSY);
2455 csdev = device_create(comedi_class, hardware_device,
2456 MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i", i);
2458 dev->class_dev = get_device(csdev);
2460 /* Note: dev->mutex needs to be unlocked by the caller. */
2464 static void comedi_free_board_minor(unsigned minor)
2466 BUG_ON(minor >= COMEDI_NUM_BOARD_MINORS);
2467 comedi_free_board_dev(comedi_clear_board_minor(minor));
2470 void comedi_release_hardware_device(struct device *hardware_device)
2473 struct comedi_device *dev;
2475 for (minor = comedi_num_legacy_minors; minor < COMEDI_NUM_BOARD_MINORS;
2477 mutex_lock(&comedi_board_minor_table_lock);
2478 dev = comedi_board_minor_table[minor];
2479 if (dev && dev->hw_dev == hardware_device) {
2480 comedi_board_minor_table[minor] = NULL;
2481 mutex_unlock(&comedi_board_minor_table_lock);
2482 comedi_free_board_dev(dev);
2485 mutex_unlock(&comedi_board_minor_table_lock);
2489 int comedi_alloc_subdevice_minor(struct comedi_subdevice *s)
2491 struct comedi_device *dev = s->device;
2492 struct device *csdev;
2495 mutex_lock(&comedi_subdevice_minor_table_lock);
2496 for (i = 0; i < COMEDI_NUM_SUBDEVICE_MINORS; ++i) {
2497 if (comedi_subdevice_minor_table[i] == NULL) {
2498 comedi_subdevice_minor_table[i] = s;
2502 mutex_unlock(&comedi_subdevice_minor_table_lock);
2503 if (i == COMEDI_NUM_SUBDEVICE_MINORS) {
2504 pr_err("ran out of minor numbers for subdevice files\n");
2507 i += COMEDI_NUM_BOARD_MINORS;
2509 csdev = device_create(comedi_class, dev->class_dev,
2510 MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i_subd%i",
2511 dev->minor, s->index);
2513 s->class_dev = csdev;
2518 void comedi_free_subdevice_minor(struct comedi_subdevice *s)
2527 BUG_ON(s->minor >= COMEDI_NUM_MINORS);
2528 BUG_ON(s->minor < COMEDI_NUM_BOARD_MINORS);
2530 i = s->minor - COMEDI_NUM_BOARD_MINORS;
2531 mutex_lock(&comedi_subdevice_minor_table_lock);
2532 if (s == comedi_subdevice_minor_table[i])
2533 comedi_subdevice_minor_table[i] = NULL;
2534 mutex_unlock(&comedi_subdevice_minor_table_lock);
2536 device_destroy(comedi_class, MKDEV(COMEDI_MAJOR, s->minor));
2537 s->class_dev = NULL;
2541 static void comedi_cleanup_board_minors(void)
2545 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++)
2546 comedi_free_board_minor(i);
2549 static int __init comedi_init(void)
2554 pr_info("version " COMEDI_RELEASE " - http://www.comedi.org\n");
2556 if (comedi_num_legacy_minors < 0 ||
2557 comedi_num_legacy_minors > COMEDI_NUM_BOARD_MINORS) {
2558 pr_err("invalid value for module parameter \"comedi_num_legacy_minors\". Valid values are 0 through %i.\n",
2559 COMEDI_NUM_BOARD_MINORS);
2563 retval = register_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2564 COMEDI_NUM_MINORS, "comedi");
2567 cdev_init(&comedi_cdev, &comedi_fops);
2568 comedi_cdev.owner = THIS_MODULE;
2570 retval = kobject_set_name(&comedi_cdev.kobj, "comedi");
2572 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2577 if (cdev_add(&comedi_cdev, MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS)) {
2578 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2582 comedi_class = class_create(THIS_MODULE, "comedi");
2583 if (IS_ERR(comedi_class)) {
2584 pr_err("failed to create class\n");
2585 cdev_del(&comedi_cdev);
2586 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2588 return PTR_ERR(comedi_class);
2591 comedi_class->dev_groups = comedi_dev_groups;
2593 /* XXX requires /proc interface */
2596 /* create devices files for legacy/manual use */
2597 for (i = 0; i < comedi_num_legacy_minors; i++) {
2598 struct comedi_device *dev;
2600 dev = comedi_alloc_board_minor(NULL);
2602 comedi_cleanup_board_minors();
2603 cdev_del(&comedi_cdev);
2604 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2606 return PTR_ERR(dev);
2608 /* comedi_alloc_board_minor() locked the mutex */
2609 mutex_unlock(&dev->mutex);
2614 module_init(comedi_init);
2616 static void __exit comedi_cleanup(void)
2620 comedi_cleanup_board_minors();
2621 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; ++i)
2622 BUG_ON(comedi_board_minor_table[i]);
2623 for (i = 0; i < COMEDI_NUM_SUBDEVICE_MINORS; ++i)
2624 BUG_ON(comedi_subdevice_minor_table[i]);
2626 class_destroy(comedi_class);
2627 cdev_del(&comedi_cdev);
2628 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS);
2630 comedi_proc_cleanup();
2632 module_exit(comedi_cleanup);
2634 MODULE_AUTHOR("http://www.comedi.org");
2635 MODULE_DESCRIPTION("Comedi core module");
2636 MODULE_LICENSE("GPL");