1 // SPDX-License-Identifier: GPL-2.0+
6 * COMEDI - Linux Control and Measurement Device Interface
7 * Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 #include "comedi_compat32.h"
14 #include <linux/module.h>
15 #include <linux/errno.h>
16 #include <linux/kernel.h>
17 #include <linux/sched/signal.h>
18 #include <linux/fcntl.h>
19 #include <linux/delay.h>
21 #include <linux/slab.h>
22 #include <linux/poll.h>
23 #include <linux/device.h>
25 #include "comedidev.h"
26 #include <linux/cdev.h>
29 #include <linux/uaccess.h>
31 #include "comedi_internal.h"
34 * comedi_subdevice "runflags"
35 * COMEDI_SRF_RT: DEPRECATED: command is running real-time
36 * COMEDI_SRF_ERROR: indicates an COMEDI_CB_ERROR event has occurred
37 * since the last command was started
38 * COMEDI_SRF_RUNNING: command is running
39 * COMEDI_SRF_FREE_SPRIV: free s->private on detach
41 * COMEDI_SRF_BUSY_MASK: runflags that indicate the subdevice is "busy"
43 #define COMEDI_SRF_RT BIT(1)
44 #define COMEDI_SRF_ERROR BIT(2)
45 #define COMEDI_SRF_RUNNING BIT(27)
46 #define COMEDI_SRF_FREE_SPRIV BIT(31)
48 #define COMEDI_SRF_BUSY_MASK (COMEDI_SRF_ERROR | COMEDI_SRF_RUNNING)
51 * struct comedi_file - Per-file private data for COMEDI device
52 * @dev: COMEDI device.
53 * @read_subdev: Current "read" subdevice.
54 * @write_subdev: Current "write" subdevice.
55 * @last_detach_count: Last known detach count.
56 * @last_attached: Last known attached/detached state.
59 struct comedi_device *dev;
60 struct comedi_subdevice *read_subdev;
61 struct comedi_subdevice *write_subdev;
62 unsigned int last_detach_count;
63 unsigned int last_attached:1;
66 #define COMEDI_NUM_MINORS 0x100
67 #define COMEDI_NUM_SUBDEVICE_MINORS \
68 (COMEDI_NUM_MINORS - COMEDI_NUM_BOARD_MINORS)
70 static unsigned short comedi_num_legacy_minors;
71 module_param(comedi_num_legacy_minors, ushort, 0444);
72 MODULE_PARM_DESC(comedi_num_legacy_minors,
73 "number of comedi minor devices to reserve for non-auto-configured devices (default 0)"
76 unsigned int comedi_default_buf_size_kb = CONFIG_COMEDI_DEFAULT_BUF_SIZE_KB;
77 module_param(comedi_default_buf_size_kb, uint, 0644);
78 MODULE_PARM_DESC(comedi_default_buf_size_kb,
79 "default asynchronous buffer size in KiB (default "
80 __MODULE_STRING(CONFIG_COMEDI_DEFAULT_BUF_SIZE_KB) ")");
82 unsigned int comedi_default_buf_maxsize_kb =
83 CONFIG_COMEDI_DEFAULT_BUF_MAXSIZE_KB;
84 module_param(comedi_default_buf_maxsize_kb, uint, 0644);
85 MODULE_PARM_DESC(comedi_default_buf_maxsize_kb,
86 "default maximum size of asynchronous buffer in KiB (default "
87 __MODULE_STRING(CONFIG_COMEDI_DEFAULT_BUF_MAXSIZE_KB) ")");
89 static DEFINE_MUTEX(comedi_board_minor_table_lock);
90 static struct comedi_device
91 *comedi_board_minor_table[COMEDI_NUM_BOARD_MINORS];
93 static DEFINE_MUTEX(comedi_subdevice_minor_table_lock);
94 /* Note: indexed by minor - COMEDI_NUM_BOARD_MINORS. */
95 static struct comedi_subdevice
96 *comedi_subdevice_minor_table[COMEDI_NUM_SUBDEVICE_MINORS];
98 static struct class *comedi_class;
99 static struct cdev comedi_cdev;
101 static void comedi_device_init(struct comedi_device *dev)
103 kref_init(&dev->refcount);
104 spin_lock_init(&dev->spinlock);
105 mutex_init(&dev->mutex);
106 init_rwsem(&dev->attach_lock);
110 static void comedi_dev_kref_release(struct kref *kref)
112 struct comedi_device *dev =
113 container_of(kref, struct comedi_device, refcount);
115 mutex_destroy(&dev->mutex);
116 put_device(dev->class_dev);
121 * comedi_dev_put() - Release a use of a COMEDI device
122 * @dev: COMEDI device.
124 * Must be called when a user of a COMEDI device is finished with it.
125 * When the last user of the COMEDI device calls this function, the
126 * COMEDI device is destroyed.
128 * Return: 1 if the COMEDI device is destroyed by this call or @dev is
129 * NULL, otherwise return 0. Callers must not assume the COMEDI
130 * device is still valid if this function returns 0.
132 int comedi_dev_put(struct comedi_device *dev)
135 return kref_put(&dev->refcount, comedi_dev_kref_release);
138 EXPORT_SYMBOL_GPL(comedi_dev_put);
140 static struct comedi_device *comedi_dev_get(struct comedi_device *dev)
143 kref_get(&dev->refcount);
147 static void comedi_device_cleanup(struct comedi_device *dev)
149 struct module *driver_module = NULL;
153 mutex_lock(&dev->mutex);
155 driver_module = dev->driver->module;
156 comedi_device_detach(dev);
157 if (driver_module && dev->use_count)
158 module_put(driver_module);
159 mutex_unlock(&dev->mutex);
162 static bool comedi_clear_board_dev(struct comedi_device *dev)
164 unsigned int i = dev->minor;
165 bool cleared = false;
167 lockdep_assert_held(&dev->mutex);
168 mutex_lock(&comedi_board_minor_table_lock);
169 if (dev == comedi_board_minor_table[i]) {
170 comedi_board_minor_table[i] = NULL;
173 mutex_unlock(&comedi_board_minor_table_lock);
177 static struct comedi_device *comedi_clear_board_minor(unsigned int minor)
179 struct comedi_device *dev;
181 mutex_lock(&comedi_board_minor_table_lock);
182 dev = comedi_board_minor_table[minor];
183 comedi_board_minor_table[minor] = NULL;
184 mutex_unlock(&comedi_board_minor_table_lock);
188 static void comedi_free_board_dev(struct comedi_device *dev)
191 comedi_device_cleanup(dev);
192 if (dev->class_dev) {
193 device_destroy(comedi_class,
194 MKDEV(COMEDI_MAJOR, dev->minor));
200 static struct comedi_subdevice *
201 comedi_subdevice_from_minor(const struct comedi_device *dev, unsigned int minor)
203 struct comedi_subdevice *s;
204 unsigned int i = minor - COMEDI_NUM_BOARD_MINORS;
206 mutex_lock(&comedi_subdevice_minor_table_lock);
207 s = comedi_subdevice_minor_table[i];
208 if (s && s->device != dev)
210 mutex_unlock(&comedi_subdevice_minor_table_lock);
214 static struct comedi_device *comedi_dev_get_from_board_minor(unsigned int minor)
216 struct comedi_device *dev;
218 mutex_lock(&comedi_board_minor_table_lock);
219 dev = comedi_dev_get(comedi_board_minor_table[minor]);
220 mutex_unlock(&comedi_board_minor_table_lock);
224 static struct comedi_device *
225 comedi_dev_get_from_subdevice_minor(unsigned int minor)
227 struct comedi_device *dev;
228 struct comedi_subdevice *s;
229 unsigned int i = minor - COMEDI_NUM_BOARD_MINORS;
231 mutex_lock(&comedi_subdevice_minor_table_lock);
232 s = comedi_subdevice_minor_table[i];
233 dev = comedi_dev_get(s ? s->device : NULL);
234 mutex_unlock(&comedi_subdevice_minor_table_lock);
239 * comedi_dev_get_from_minor() - Get COMEDI device by minor device number
240 * @minor: Minor device number.
242 * Finds the COMEDI device associated with the minor device number, if any,
243 * and increments its reference count. The COMEDI device is prevented from
244 * being freed until a matching call is made to comedi_dev_put().
246 * Return: A pointer to the COMEDI device if it exists, with its usage
247 * reference incremented. Return NULL if no COMEDI device exists with the
248 * specified minor device number.
250 struct comedi_device *comedi_dev_get_from_minor(unsigned int minor)
252 if (minor < COMEDI_NUM_BOARD_MINORS)
253 return comedi_dev_get_from_board_minor(minor);
255 return comedi_dev_get_from_subdevice_minor(minor);
257 EXPORT_SYMBOL_GPL(comedi_dev_get_from_minor);
259 static struct comedi_subdevice *
260 comedi_read_subdevice(const struct comedi_device *dev, unsigned int minor)
262 struct comedi_subdevice *s;
264 lockdep_assert_held(&dev->mutex);
265 if (minor >= COMEDI_NUM_BOARD_MINORS) {
266 s = comedi_subdevice_from_minor(dev, minor);
267 if (!s || (s->subdev_flags & SDF_CMD_READ))
270 return dev->read_subdev;
273 static struct comedi_subdevice *
274 comedi_write_subdevice(const struct comedi_device *dev, unsigned int minor)
276 struct comedi_subdevice *s;
278 lockdep_assert_held(&dev->mutex);
279 if (minor >= COMEDI_NUM_BOARD_MINORS) {
280 s = comedi_subdevice_from_minor(dev, minor);
281 if (!s || (s->subdev_flags & SDF_CMD_WRITE))
284 return dev->write_subdev;
287 static void comedi_file_reset(struct file *file)
289 struct comedi_file *cfp = file->private_data;
290 struct comedi_device *dev = cfp->dev;
291 struct comedi_subdevice *s, *read_s, *write_s;
292 unsigned int minor = iminor(file_inode(file));
294 read_s = dev->read_subdev;
295 write_s = dev->write_subdev;
296 if (minor >= COMEDI_NUM_BOARD_MINORS) {
297 s = comedi_subdevice_from_minor(dev, minor);
298 if (!s || s->subdev_flags & SDF_CMD_READ)
300 if (!s || s->subdev_flags & SDF_CMD_WRITE)
303 cfp->last_attached = dev->attached;
304 cfp->last_detach_count = dev->detach_count;
305 WRITE_ONCE(cfp->read_subdev, read_s);
306 WRITE_ONCE(cfp->write_subdev, write_s);
309 static void comedi_file_check(struct file *file)
311 struct comedi_file *cfp = file->private_data;
312 struct comedi_device *dev = cfp->dev;
314 if (cfp->last_attached != dev->attached ||
315 cfp->last_detach_count != dev->detach_count)
316 comedi_file_reset(file);
319 static struct comedi_subdevice *comedi_file_read_subdevice(struct file *file)
321 struct comedi_file *cfp = file->private_data;
323 comedi_file_check(file);
324 return READ_ONCE(cfp->read_subdev);
327 static struct comedi_subdevice *comedi_file_write_subdevice(struct file *file)
329 struct comedi_file *cfp = file->private_data;
331 comedi_file_check(file);
332 return READ_ONCE(cfp->write_subdev);
335 static int resize_async_buffer(struct comedi_device *dev,
336 struct comedi_subdevice *s,
337 unsigned int new_size)
339 struct comedi_async *async = s->async;
342 lockdep_assert_held(&dev->mutex);
344 if (new_size > async->max_bufsize)
348 dev_dbg(dev->class_dev,
349 "subdevice is busy, cannot resize buffer\n");
352 if (comedi_buf_is_mmapped(s)) {
353 dev_dbg(dev->class_dev,
354 "subdevice is mmapped, cannot resize buffer\n");
358 /* make sure buffer is an integral number of pages (we round up) */
359 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK;
361 retval = comedi_buf_alloc(dev, s, new_size);
366 retval = s->buf_change(dev, s);
371 dev_dbg(dev->class_dev, "subd %d buffer resized to %i bytes\n",
372 s->index, async->prealloc_bufsz);
376 /* sysfs attribute files */
378 static ssize_t max_read_buffer_kb_show(struct device *csdev,
379 struct device_attribute *attr, char *buf)
381 unsigned int minor = MINOR(csdev->devt);
382 struct comedi_device *dev;
383 struct comedi_subdevice *s;
384 unsigned int size = 0;
386 dev = comedi_dev_get_from_minor(minor);
390 mutex_lock(&dev->mutex);
391 s = comedi_read_subdevice(dev, minor);
392 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
393 size = s->async->max_bufsize / 1024;
394 mutex_unlock(&dev->mutex);
397 return snprintf(buf, PAGE_SIZE, "%u\n", size);
400 static ssize_t max_read_buffer_kb_store(struct device *csdev,
401 struct device_attribute *attr,
402 const char *buf, size_t count)
404 unsigned int minor = MINOR(csdev->devt);
405 struct comedi_device *dev;
406 struct comedi_subdevice *s;
410 err = kstrtouint(buf, 10, &size);
413 if (size > (UINT_MAX / 1024))
417 dev = comedi_dev_get_from_minor(minor);
421 mutex_lock(&dev->mutex);
422 s = comedi_read_subdevice(dev, minor);
423 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
424 s->async->max_bufsize = size;
427 mutex_unlock(&dev->mutex);
430 return err ? err : count;
432 static DEVICE_ATTR_RW(max_read_buffer_kb);
434 static ssize_t read_buffer_kb_show(struct device *csdev,
435 struct device_attribute *attr, char *buf)
437 unsigned int minor = MINOR(csdev->devt);
438 struct comedi_device *dev;
439 struct comedi_subdevice *s;
440 unsigned int size = 0;
442 dev = comedi_dev_get_from_minor(minor);
446 mutex_lock(&dev->mutex);
447 s = comedi_read_subdevice(dev, minor);
448 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
449 size = s->async->prealloc_bufsz / 1024;
450 mutex_unlock(&dev->mutex);
453 return snprintf(buf, PAGE_SIZE, "%u\n", size);
456 static ssize_t read_buffer_kb_store(struct device *csdev,
457 struct device_attribute *attr,
458 const char *buf, size_t count)
460 unsigned int minor = MINOR(csdev->devt);
461 struct comedi_device *dev;
462 struct comedi_subdevice *s;
466 err = kstrtouint(buf, 10, &size);
469 if (size > (UINT_MAX / 1024))
473 dev = comedi_dev_get_from_minor(minor);
477 mutex_lock(&dev->mutex);
478 s = comedi_read_subdevice(dev, minor);
479 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
480 err = resize_async_buffer(dev, s, size);
483 mutex_unlock(&dev->mutex);
486 return err ? err : count;
488 static DEVICE_ATTR_RW(read_buffer_kb);
490 static ssize_t max_write_buffer_kb_show(struct device *csdev,
491 struct device_attribute *attr,
494 unsigned int minor = MINOR(csdev->devt);
495 struct comedi_device *dev;
496 struct comedi_subdevice *s;
497 unsigned int size = 0;
499 dev = comedi_dev_get_from_minor(minor);
503 mutex_lock(&dev->mutex);
504 s = comedi_write_subdevice(dev, minor);
505 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
506 size = s->async->max_bufsize / 1024;
507 mutex_unlock(&dev->mutex);
510 return snprintf(buf, PAGE_SIZE, "%u\n", size);
513 static ssize_t max_write_buffer_kb_store(struct device *csdev,
514 struct device_attribute *attr,
515 const char *buf, size_t count)
517 unsigned int minor = MINOR(csdev->devt);
518 struct comedi_device *dev;
519 struct comedi_subdevice *s;
523 err = kstrtouint(buf, 10, &size);
526 if (size > (UINT_MAX / 1024))
530 dev = comedi_dev_get_from_minor(minor);
534 mutex_lock(&dev->mutex);
535 s = comedi_write_subdevice(dev, minor);
536 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
537 s->async->max_bufsize = size;
540 mutex_unlock(&dev->mutex);
543 return err ? err : count;
545 static DEVICE_ATTR_RW(max_write_buffer_kb);
547 static ssize_t write_buffer_kb_show(struct device *csdev,
548 struct device_attribute *attr, char *buf)
550 unsigned int minor = MINOR(csdev->devt);
551 struct comedi_device *dev;
552 struct comedi_subdevice *s;
553 unsigned int size = 0;
555 dev = comedi_dev_get_from_minor(minor);
559 mutex_lock(&dev->mutex);
560 s = comedi_write_subdevice(dev, minor);
561 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
562 size = s->async->prealloc_bufsz / 1024;
563 mutex_unlock(&dev->mutex);
566 return snprintf(buf, PAGE_SIZE, "%u\n", size);
569 static ssize_t write_buffer_kb_store(struct device *csdev,
570 struct device_attribute *attr,
571 const char *buf, size_t count)
573 unsigned int minor = MINOR(csdev->devt);
574 struct comedi_device *dev;
575 struct comedi_subdevice *s;
579 err = kstrtouint(buf, 10, &size);
582 if (size > (UINT_MAX / 1024))
586 dev = comedi_dev_get_from_minor(minor);
590 mutex_lock(&dev->mutex);
591 s = comedi_write_subdevice(dev, minor);
592 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
593 err = resize_async_buffer(dev, s, size);
596 mutex_unlock(&dev->mutex);
599 return err ? err : count;
601 static DEVICE_ATTR_RW(write_buffer_kb);
603 static struct attribute *comedi_dev_attrs[] = {
604 &dev_attr_max_read_buffer_kb.attr,
605 &dev_attr_read_buffer_kb.attr,
606 &dev_attr_max_write_buffer_kb.attr,
607 &dev_attr_write_buffer_kb.attr,
610 ATTRIBUTE_GROUPS(comedi_dev);
612 static void __comedi_clear_subdevice_runflags(struct comedi_subdevice *s,
615 s->runflags &= ~bits;
618 static void __comedi_set_subdevice_runflags(struct comedi_subdevice *s,
624 static void comedi_update_subdevice_runflags(struct comedi_subdevice *s,
630 spin_lock_irqsave(&s->spin_lock, flags);
631 __comedi_clear_subdevice_runflags(s, mask);
632 __comedi_set_subdevice_runflags(s, bits & mask);
633 spin_unlock_irqrestore(&s->spin_lock, flags);
636 static unsigned int __comedi_get_subdevice_runflags(struct comedi_subdevice *s)
641 static unsigned int comedi_get_subdevice_runflags(struct comedi_subdevice *s)
644 unsigned int runflags;
646 spin_lock_irqsave(&s->spin_lock, flags);
647 runflags = __comedi_get_subdevice_runflags(s);
648 spin_unlock_irqrestore(&s->spin_lock, flags);
652 static bool comedi_is_runflags_running(unsigned int runflags)
654 return runflags & COMEDI_SRF_RUNNING;
657 static bool comedi_is_runflags_in_error(unsigned int runflags)
659 return runflags & COMEDI_SRF_ERROR;
663 * comedi_is_subdevice_running() - Check if async command running on subdevice
664 * @s: COMEDI subdevice.
666 * Return: %true if an asynchronous COMEDI command is active on the
667 * subdevice, else %false.
669 bool comedi_is_subdevice_running(struct comedi_subdevice *s)
671 unsigned int runflags = comedi_get_subdevice_runflags(s);
673 return comedi_is_runflags_running(runflags);
675 EXPORT_SYMBOL_GPL(comedi_is_subdevice_running);
677 static bool __comedi_is_subdevice_running(struct comedi_subdevice *s)
679 unsigned int runflags = __comedi_get_subdevice_runflags(s);
681 return comedi_is_runflags_running(runflags);
684 bool comedi_can_auto_free_spriv(struct comedi_subdevice *s)
686 unsigned int runflags = __comedi_get_subdevice_runflags(s);
688 return runflags & COMEDI_SRF_FREE_SPRIV;
692 * comedi_set_spriv_auto_free() - Mark subdevice private data as freeable
693 * @s: COMEDI subdevice.
695 * Mark the subdevice as having a pointer to private data that can be
696 * automatically freed when the COMEDI device is detached from the low-level
699 void comedi_set_spriv_auto_free(struct comedi_subdevice *s)
701 __comedi_set_subdevice_runflags(s, COMEDI_SRF_FREE_SPRIV);
703 EXPORT_SYMBOL_GPL(comedi_set_spriv_auto_free);
706 * comedi_alloc_spriv - Allocate memory for the subdevice private data
707 * @s: COMEDI subdevice.
708 * @size: Size of the memory to allocate.
710 * Allocate memory for the subdevice private data and point @s->private
711 * to it. The memory will be freed automatically when the COMEDI device
712 * is detached from the low-level driver.
714 * Return: A pointer to the allocated memory @s->private on success.
715 * Return NULL on failure.
717 void *comedi_alloc_spriv(struct comedi_subdevice *s, size_t size)
719 s->private = kzalloc(size, GFP_KERNEL);
721 comedi_set_spriv_auto_free(s);
724 EXPORT_SYMBOL_GPL(comedi_alloc_spriv);
727 * This function restores a subdevice to an idle state.
729 static void do_become_nonbusy(struct comedi_device *dev,
730 struct comedi_subdevice *s)
732 struct comedi_async *async = s->async;
734 lockdep_assert_held(&dev->mutex);
735 comedi_update_subdevice_runflags(s, COMEDI_SRF_RUNNING, 0);
738 async->inttrig = NULL;
739 kfree(async->cmd.chanlist);
740 async->cmd.chanlist = NULL;
742 wake_up_interruptible_all(&async->wait_head);
744 dev_err(dev->class_dev,
745 "BUG: (?) %s called with async=NULL\n", __func__);
750 static int do_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
754 lockdep_assert_held(&dev->mutex);
755 if (comedi_is_subdevice_running(s) && s->cancel)
756 ret = s->cancel(dev, s);
758 do_become_nonbusy(dev, s);
763 void comedi_device_cancel_all(struct comedi_device *dev)
765 struct comedi_subdevice *s;
768 lockdep_assert_held(&dev->mutex);
772 for (i = 0; i < dev->n_subdevices; i++) {
773 s = &dev->subdevices[i];
779 static int is_device_busy(struct comedi_device *dev)
781 struct comedi_subdevice *s;
784 lockdep_assert_held(&dev->mutex);
788 for (i = 0; i < dev->n_subdevices; i++) {
789 s = &dev->subdevices[i];
792 if (s->async && comedi_buf_is_mmapped(s))
800 * COMEDI_DEVCONFIG ioctl
801 * attaches (and configures) or detaches a legacy device
804 * pointer to comedi_devconfig structure (NULL if detaching)
807 * comedi_devconfig structure (if attaching)
812 static int do_devconfig_ioctl(struct comedi_device *dev,
813 struct comedi_devconfig __user *arg)
815 struct comedi_devconfig it;
817 lockdep_assert_held(&dev->mutex);
818 if (!capable(CAP_SYS_ADMIN))
822 if (is_device_busy(dev))
825 struct module *driver_module = dev->driver->module;
827 comedi_device_detach(dev);
828 module_put(driver_module);
833 if (copy_from_user(&it, arg, sizeof(it)))
836 it.board_name[COMEDI_NAMELEN - 1] = 0;
838 if (it.options[COMEDI_DEVCONF_AUX_DATA_LENGTH]) {
839 dev_warn(dev->class_dev,
840 "comedi_config --init_data is deprecated\n");
844 if (dev->minor >= comedi_num_legacy_minors)
845 /* don't re-use dynamically allocated comedi devices */
848 /* This increments the driver module count on success. */
849 return comedi_device_attach(dev, &it);
853 * COMEDI_BUFCONFIG ioctl
854 * buffer configuration
857 * pointer to comedi_bufconfig structure
860 * comedi_bufconfig structure
863 * modified comedi_bufconfig structure
865 static int do_bufconfig_ioctl(struct comedi_device *dev,
866 struct comedi_bufconfig __user *arg)
868 struct comedi_bufconfig bc;
869 struct comedi_async *async;
870 struct comedi_subdevice *s;
873 lockdep_assert_held(&dev->mutex);
874 if (copy_from_user(&bc, arg, sizeof(bc)))
877 if (bc.subdevice >= dev->n_subdevices)
880 s = &dev->subdevices[bc.subdevice];
884 dev_dbg(dev->class_dev,
885 "subdevice does not have async capability\n");
891 if (bc.maximum_size) {
892 if (!capable(CAP_SYS_ADMIN))
895 async->max_bufsize = bc.maximum_size;
899 retval = resize_async_buffer(dev, s, bc.size);
904 bc.size = async->prealloc_bufsz;
905 bc.maximum_size = async->max_bufsize;
908 if (copy_to_user(arg, &bc, sizeof(bc)))
915 * COMEDI_DEVINFO ioctl
919 * pointer to comedi_devinfo structure
925 * comedi_devinfo structure
927 static int do_devinfo_ioctl(struct comedi_device *dev,
928 struct comedi_devinfo __user *arg,
931 struct comedi_subdevice *s;
932 struct comedi_devinfo devinfo;
934 lockdep_assert_held(&dev->mutex);
935 memset(&devinfo, 0, sizeof(devinfo));
937 /* fill devinfo structure */
938 devinfo.version_code = COMEDI_VERSION_CODE;
939 devinfo.n_subdevs = dev->n_subdevices;
940 strlcpy(devinfo.driver_name, dev->driver->driver_name, COMEDI_NAMELEN);
941 strlcpy(devinfo.board_name, dev->board_name, COMEDI_NAMELEN);
943 s = comedi_file_read_subdevice(file);
945 devinfo.read_subdevice = s->index;
947 devinfo.read_subdevice = -1;
949 s = comedi_file_write_subdevice(file);
951 devinfo.write_subdevice = s->index;
953 devinfo.write_subdevice = -1;
955 if (copy_to_user(arg, &devinfo, sizeof(devinfo)))
962 * COMEDI_SUBDINFO ioctl
966 * pointer to array of comedi_subdinfo structures
972 * array of comedi_subdinfo structures
974 static int do_subdinfo_ioctl(struct comedi_device *dev,
975 struct comedi_subdinfo __user *arg, void *file)
978 struct comedi_subdinfo *tmp, *us;
979 struct comedi_subdevice *s;
981 lockdep_assert_held(&dev->mutex);
982 tmp = kcalloc(dev->n_subdevices, sizeof(*tmp), GFP_KERNEL);
986 /* fill subdinfo structs */
987 for (i = 0; i < dev->n_subdevices; i++) {
988 s = &dev->subdevices[i];
992 us->n_chan = s->n_chan;
993 us->subd_flags = s->subdev_flags;
994 if (comedi_is_subdevice_running(s))
995 us->subd_flags |= SDF_RUNNING;
996 #define TIMER_nanosec 5 /* backwards compatibility */
997 us->timer_type = TIMER_nanosec;
998 us->len_chanlist = s->len_chanlist;
999 us->maxdata = s->maxdata;
1000 if (s->range_table) {
1002 (i << 24) | (0 << 16) | (s->range_table->length);
1004 us->range_type = 0; /* XXX */
1008 us->subd_flags |= SDF_BUSY;
1009 if (s->busy == file)
1010 us->subd_flags |= SDF_BUSY_OWNER;
1012 us->subd_flags |= SDF_LOCKED;
1013 if (s->lock == file)
1014 us->subd_flags |= SDF_LOCK_OWNER;
1015 if (!s->maxdata && s->maxdata_list)
1016 us->subd_flags |= SDF_MAXDATA;
1017 if (s->range_table_list)
1018 us->subd_flags |= SDF_RANGETYPE;
1020 us->subd_flags |= SDF_CMD;
1022 if (s->insn_bits != &insn_inval)
1023 us->insn_bits_support = COMEDI_SUPPORTED;
1025 us->insn_bits_support = COMEDI_UNSUPPORTED;
1028 ret = copy_to_user(arg, tmp, dev->n_subdevices * sizeof(*tmp));
1032 return ret ? -EFAULT : 0;
1036 * COMEDI_CHANINFO ioctl
1037 * subdevice channel info
1040 * pointer to comedi_chaninfo structure
1043 * comedi_chaninfo structure
1046 * array of maxdata values to chaninfo->maxdata_list if requested
1047 * array of range table lengths to chaninfo->range_table_list if requested
1049 static int do_chaninfo_ioctl(struct comedi_device *dev,
1050 struct comedi_chaninfo __user *arg)
1052 struct comedi_subdevice *s;
1053 struct comedi_chaninfo it;
1055 lockdep_assert_held(&dev->mutex);
1056 if (copy_from_user(&it, arg, sizeof(it)))
1059 if (it.subdev >= dev->n_subdevices)
1061 s = &dev->subdevices[it.subdev];
1063 if (it.maxdata_list) {
1064 if (s->maxdata || !s->maxdata_list)
1066 if (copy_to_user(it.maxdata_list, s->maxdata_list,
1067 s->n_chan * sizeof(unsigned int)))
1072 return -EINVAL; /* flaglist not supported */
1077 if (!s->range_table_list)
1079 for (i = 0; i < s->n_chan; i++) {
1082 x = (dev->minor << 28) | (it.subdev << 24) | (i << 16) |
1083 (s->range_table_list[i]->length);
1084 if (put_user(x, it.rangelist + i))
1093 * COMEDI_BUFINFO ioctl
1094 * buffer information
1097 * pointer to comedi_bufinfo structure
1100 * comedi_bufinfo structure
1103 * modified comedi_bufinfo structure
1105 static int do_bufinfo_ioctl(struct comedi_device *dev,
1106 struct comedi_bufinfo __user *arg, void *file)
1108 struct comedi_bufinfo bi;
1109 struct comedi_subdevice *s;
1110 struct comedi_async *async;
1111 unsigned int runflags;
1113 bool become_nonbusy = false;
1115 lockdep_assert_held(&dev->mutex);
1116 if (copy_from_user(&bi, arg, sizeof(bi)))
1119 if (bi.subdevice >= dev->n_subdevices)
1122 s = &dev->subdevices[bi.subdevice];
1126 if (!async || s->busy != file)
1129 runflags = comedi_get_subdevice_runflags(s);
1130 if (!(async->cmd.flags & CMDF_WRITE)) {
1131 /* command was set up in "read" direction */
1132 if (bi.bytes_read) {
1133 comedi_buf_read_alloc(s, bi.bytes_read);
1134 bi.bytes_read = comedi_buf_read_free(s, bi.bytes_read);
1137 * If nothing left to read, and command has stopped, and
1138 * {"read" position not updated or command stopped normally},
1139 * then become non-busy.
1141 if (comedi_buf_read_n_available(s) == 0 &&
1142 !comedi_is_runflags_running(runflags) &&
1143 (bi.bytes_read == 0 ||
1144 !comedi_is_runflags_in_error(runflags))) {
1145 become_nonbusy = true;
1146 if (comedi_is_runflags_in_error(runflags))
1149 bi.bytes_written = 0;
1151 /* command was set up in "write" direction */
1152 if (!comedi_is_runflags_running(runflags)) {
1153 bi.bytes_written = 0;
1154 become_nonbusy = true;
1155 if (comedi_is_runflags_in_error(runflags))
1157 } else if (bi.bytes_written) {
1158 comedi_buf_write_alloc(s, bi.bytes_written);
1160 comedi_buf_write_free(s, bi.bytes_written);
1165 bi.buf_write_count = async->buf_write_count;
1166 bi.buf_write_ptr = async->buf_write_ptr;
1167 bi.buf_read_count = async->buf_read_count;
1168 bi.buf_read_ptr = async->buf_read_ptr;
1171 do_become_nonbusy(dev, s);
1176 if (copy_to_user(arg, &bi, sizeof(bi)))
1182 static int check_insn_config_length(struct comedi_insn *insn,
1189 case INSN_CONFIG_DIO_OUTPUT:
1190 case INSN_CONFIG_DIO_INPUT:
1191 case INSN_CONFIG_DISARM:
1192 case INSN_CONFIG_RESET:
1196 case INSN_CONFIG_ARM:
1197 case INSN_CONFIG_DIO_QUERY:
1198 case INSN_CONFIG_BLOCK_SIZE:
1199 case INSN_CONFIG_FILTER:
1200 case INSN_CONFIG_SERIAL_CLOCK:
1201 case INSN_CONFIG_BIDIRECTIONAL_DATA:
1202 case INSN_CONFIG_ALT_SOURCE:
1203 case INSN_CONFIG_SET_COUNTER_MODE:
1204 case INSN_CONFIG_8254_READ_STATUS:
1205 case INSN_CONFIG_SET_ROUTING:
1206 case INSN_CONFIG_GET_ROUTING:
1207 case INSN_CONFIG_GET_PWM_STATUS:
1208 case INSN_CONFIG_PWM_SET_PERIOD:
1209 case INSN_CONFIG_PWM_GET_PERIOD:
1213 case INSN_CONFIG_SET_GATE_SRC:
1214 case INSN_CONFIG_GET_GATE_SRC:
1215 case INSN_CONFIG_SET_CLOCK_SRC:
1216 case INSN_CONFIG_GET_CLOCK_SRC:
1217 case INSN_CONFIG_SET_OTHER_SRC:
1218 case INSN_CONFIG_GET_COUNTER_STATUS:
1219 case INSN_CONFIG_PWM_SET_H_BRIDGE:
1220 case INSN_CONFIG_PWM_GET_H_BRIDGE:
1221 case INSN_CONFIG_GET_HARDWARE_BUFFER_SIZE:
1225 case INSN_CONFIG_PWM_OUTPUT:
1226 case INSN_CONFIG_ANALOG_TRIG:
1227 case INSN_CONFIG_TIMER_1:
1231 case INSN_CONFIG_DIGITAL_TRIG:
1235 case INSN_CONFIG_GET_CMD_TIMING_CONSTRAINTS:
1240 * by default we allow the insn since we don't have checks for
1241 * all possible cases yet
1244 pr_warn("No check for data length of config insn id %i is implemented\n",
1246 pr_warn("Add a check to %s in %s\n", __func__, __FILE__);
1247 pr_warn("Assuming n=%i is correct\n", insn->n);
1253 static int check_insn_device_config_length(struct comedi_insn *insn,
1260 case INSN_DEVICE_CONFIG_TEST_ROUTE:
1261 case INSN_DEVICE_CONFIG_CONNECT_ROUTE:
1262 case INSN_DEVICE_CONFIG_DISCONNECT_ROUTE:
1266 case INSN_DEVICE_CONFIG_GET_ROUTES:
1268 * Big enough for config_id and the length of the userland
1269 * memory buffer. Additional length should be in factors of 2
1270 * to communicate any returned route pairs (source,destination).
1280 * get_valid_routes() - Calls low-level driver get_valid_routes function to
1281 * either return a count of valid routes to user, or copy
1282 * of list of all valid device routes to buffer in
1284 * @dev: comedi device pointer
1285 * @data: data from user insn call. The length of the data must be >= 2.
1286 * data[0] must contain the INSN_DEVICE_CONFIG config_id.
1287 * data[1](input) contains the number of _pairs_ for which memory is
1288 * allotted from the user. If the user specifies '0', then only
1289 * the number of pairs available is returned.
1290 * data[1](output) returns either the number of pairs available (if none
1291 * where requested) or the number of _pairs_ that are copied back
1293 * data[2::2] returns each (source, destination) pair.
1295 * Return: -EINVAL if low-level driver does not allocate and return routes as
1296 * expected. Returns 0 otherwise.
1298 static int get_valid_routes(struct comedi_device *dev, unsigned int *data)
1300 lockdep_assert_held(&dev->mutex);
1301 data[1] = dev->get_valid_routes(dev, data[1], data + 2);
1305 static int parse_insn(struct comedi_device *dev, struct comedi_insn *insn,
1306 unsigned int *data, void *file)
1308 struct comedi_subdevice *s;
1312 lockdep_assert_held(&dev->mutex);
1313 if (insn->insn & INSN_MASK_SPECIAL) {
1314 /* a non-subdevice instruction */
1316 switch (insn->insn) {
1319 struct timespec64 tv;
1326 ktime_get_real_ts64(&tv);
1327 /* unsigned data safe until 2106 */
1328 data[0] = (unsigned int)tv.tv_sec;
1329 data[1] = tv.tv_nsec / NSEC_PER_USEC;
1335 if (insn->n != 1 || data[0] >= 100000) {
1339 udelay(data[0] / 1000);
1347 if (insn->subdev >= dev->n_subdevices) {
1348 dev_dbg(dev->class_dev,
1349 "%d not usable subdevice\n",
1354 s = &dev->subdevices[insn->subdev];
1356 dev_dbg(dev->class_dev, "no async\n");
1360 if (!s->async->inttrig) {
1361 dev_dbg(dev->class_dev, "no inttrig\n");
1365 ret = s->async->inttrig(dev, s, data[0]);
1369 case INSN_DEVICE_CONFIG:
1370 ret = check_insn_device_config_length(insn, data);
1374 if (data[0] == INSN_DEVICE_CONFIG_GET_ROUTES) {
1376 * data[1] should be the number of _pairs_ that
1377 * the memory can hold.
1379 data[1] = (insn->n - 2) / 2;
1380 ret = get_valid_routes(dev, data);
1384 /* other global device config instructions. */
1385 ret = dev->insn_device_config(dev, insn, data);
1388 dev_dbg(dev->class_dev, "invalid insn\n");
1393 /* a subdevice instruction */
1394 unsigned int maxdata;
1396 if (insn->subdev >= dev->n_subdevices) {
1397 dev_dbg(dev->class_dev, "subdevice %d out of range\n",
1402 s = &dev->subdevices[insn->subdev];
1404 if (s->type == COMEDI_SUBD_UNUSED) {
1405 dev_dbg(dev->class_dev, "%d not usable subdevice\n",
1411 /* are we locked? (ioctl lock) */
1412 if (s->lock && s->lock != file) {
1413 dev_dbg(dev->class_dev, "device locked\n");
1418 ret = comedi_check_chanlist(s, 1, &insn->chanspec);
1421 dev_dbg(dev->class_dev, "bad chanspec\n");
1429 /* This looks arbitrary. It is. */
1430 s->busy = parse_insn;
1431 switch (insn->insn) {
1433 ret = s->insn_read(dev, s, insn, data);
1434 if (ret == -ETIMEDOUT) {
1435 dev_dbg(dev->class_dev,
1436 "subdevice %d read instruction timed out\n",
1441 maxdata = s->maxdata_list
1442 ? s->maxdata_list[CR_CHAN(insn->chanspec)]
1444 for (i = 0; i < insn->n; ++i) {
1445 if (data[i] > maxdata) {
1447 dev_dbg(dev->class_dev,
1448 "bad data value(s)\n");
1453 ret = s->insn_write(dev, s, insn, data);
1454 if (ret == -ETIMEDOUT) {
1455 dev_dbg(dev->class_dev,
1456 "subdevice %d write instruction timed out\n",
1466 * Most drivers ignore the base channel in
1467 * insn->chanspec. Fix this here if
1468 * the subdevice has <= 32 channels.
1470 unsigned int orig_mask = data[0];
1471 unsigned int shift = 0;
1473 if (s->n_chan <= 32) {
1474 shift = CR_CHAN(insn->chanspec);
1481 ret = s->insn_bits(dev, s, insn, data);
1482 data[0] = orig_mask;
1488 ret = check_insn_config_length(insn, data);
1491 ret = s->insn_config(dev, s, insn, data);
1506 * COMEDI_INSNLIST ioctl
1507 * synchronous instruction list
1510 * pointer to comedi_insnlist structure
1513 * comedi_insnlist structure
1514 * array of comedi_insn structures from insnlist->insns pointer
1515 * data (for writes) from insns[].data pointers
1518 * data (for reads) to insns[].data pointers
1520 /* arbitrary limits */
1521 #define MIN_SAMPLES 16
1522 #define MAX_SAMPLES 65536
1523 static int do_insnlist_ioctl(struct comedi_device *dev,
1524 struct comedi_insnlist __user *arg, void *file)
1526 struct comedi_insnlist insnlist;
1527 struct comedi_insn *insns = NULL;
1528 unsigned int *data = NULL;
1529 unsigned int max_n_data_required = MIN_SAMPLES;
1533 lockdep_assert_held(&dev->mutex);
1534 if (copy_from_user(&insnlist, arg, sizeof(insnlist)))
1537 insns = kcalloc(insnlist.n_insns, sizeof(*insns), GFP_KERNEL);
1543 if (copy_from_user(insns, insnlist.insns,
1544 sizeof(*insns) * insnlist.n_insns)) {
1545 dev_dbg(dev->class_dev, "copy_from_user failed\n");
1550 /* Determine maximum memory needed for all instructions. */
1551 for (i = 0; i < insnlist.n_insns; ++i) {
1552 if (insns[i].n > MAX_SAMPLES) {
1553 dev_dbg(dev->class_dev,
1554 "number of samples too large\n");
1558 max_n_data_required = max(max_n_data_required, insns[i].n);
1561 /* Allocate scratch space for all instruction data. */
1562 data = kmalloc_array(max_n_data_required, sizeof(unsigned int),
1569 for (i = 0; i < insnlist.n_insns; ++i) {
1570 if (insns[i].insn & INSN_MASK_WRITE) {
1571 if (copy_from_user(data, insns[i].data,
1572 insns[i].n * sizeof(unsigned int))) {
1573 dev_dbg(dev->class_dev,
1574 "copy_from_user failed\n");
1579 ret = parse_insn(dev, insns + i, data, file);
1582 if (insns[i].insn & INSN_MASK_READ) {
1583 if (copy_to_user(insns[i].data, data,
1584 insns[i].n * sizeof(unsigned int))) {
1585 dev_dbg(dev->class_dev,
1586 "copy_to_user failed\n");
1606 * synchronous instruction
1609 * pointer to comedi_insn structure
1612 * comedi_insn structure
1613 * data (for writes) from insn->data pointer
1616 * data (for reads) to insn->data pointer
1618 static int do_insn_ioctl(struct comedi_device *dev,
1619 struct comedi_insn __user *arg, void *file)
1621 struct comedi_insn insn;
1622 unsigned int *data = NULL;
1623 unsigned int n_data = MIN_SAMPLES;
1626 lockdep_assert_held(&dev->mutex);
1627 if (copy_from_user(&insn, arg, sizeof(insn)))
1630 n_data = max(n_data, insn.n);
1632 /* This is where the behavior of insn and insnlist deviate. */
1633 if (insn.n > MAX_SAMPLES) {
1634 insn.n = MAX_SAMPLES;
1635 n_data = MAX_SAMPLES;
1638 data = kmalloc_array(n_data, sizeof(unsigned int), GFP_KERNEL);
1644 if (insn.insn & INSN_MASK_WRITE) {
1645 if (copy_from_user(data,
1647 insn.n * sizeof(unsigned int))) {
1652 ret = parse_insn(dev, &insn, data, file);
1655 if (insn.insn & INSN_MASK_READ) {
1656 if (copy_to_user(insn.data,
1658 insn.n * sizeof(unsigned int))) {
1671 static int __comedi_get_user_cmd(struct comedi_device *dev,
1672 struct comedi_cmd __user *arg,
1673 struct comedi_cmd *cmd)
1675 struct comedi_subdevice *s;
1677 lockdep_assert_held(&dev->mutex);
1678 if (copy_from_user(cmd, arg, sizeof(*cmd))) {
1679 dev_dbg(dev->class_dev, "bad cmd address\n");
1683 if (cmd->subdev >= dev->n_subdevices) {
1684 dev_dbg(dev->class_dev, "%d no such subdevice\n", cmd->subdev);
1688 s = &dev->subdevices[cmd->subdev];
1690 if (s->type == COMEDI_SUBD_UNUSED) {
1691 dev_dbg(dev->class_dev, "%d not valid subdevice\n",
1696 if (!s->do_cmd || !s->do_cmdtest || !s->async) {
1697 dev_dbg(dev->class_dev,
1698 "subdevice %d does not support commands\n",
1703 /* make sure channel/gain list isn't too long */
1704 if (cmd->chanlist_len > s->len_chanlist) {
1705 dev_dbg(dev->class_dev, "channel/gain list too long %d > %d\n",
1706 cmd->chanlist_len, s->len_chanlist);
1711 * Set the CMDF_WRITE flag to the correct state if the subdevice
1712 * supports only "read" commands or only "write" commands.
1714 switch (s->subdev_flags & (SDF_CMD_READ | SDF_CMD_WRITE)) {
1716 cmd->flags &= ~CMDF_WRITE;
1719 cmd->flags |= CMDF_WRITE;
1728 static int __comedi_get_user_chanlist(struct comedi_device *dev,
1729 struct comedi_subdevice *s,
1730 unsigned int __user *user_chanlist,
1731 struct comedi_cmd *cmd)
1733 unsigned int *chanlist;
1736 lockdep_assert_held(&dev->mutex);
1737 cmd->chanlist = NULL;
1738 chanlist = memdup_user(user_chanlist,
1739 cmd->chanlist_len * sizeof(unsigned int));
1740 if (IS_ERR(chanlist))
1741 return PTR_ERR(chanlist);
1743 /* make sure each element in channel/gain list is valid */
1744 ret = comedi_check_chanlist(s, cmd->chanlist_len, chanlist);
1750 cmd->chanlist = chanlist;
1757 * asynchronous acquisition command set-up
1760 * pointer to comedi_cmd structure
1763 * comedi_cmd structure
1764 * channel/range list from cmd->chanlist pointer
1767 * possibly modified comedi_cmd structure (when -EAGAIN returned)
1769 static int do_cmd_ioctl(struct comedi_device *dev,
1770 struct comedi_cmd __user *arg, void *file)
1772 struct comedi_cmd cmd;
1773 struct comedi_subdevice *s;
1774 struct comedi_async *async;
1775 unsigned int __user *user_chanlist;
1778 lockdep_assert_held(&dev->mutex);
1780 /* get the user's cmd and do some simple validation */
1781 ret = __comedi_get_user_cmd(dev, arg, &cmd);
1785 /* save user's chanlist pointer so it can be restored later */
1786 user_chanlist = (unsigned int __user *)cmd.chanlist;
1788 s = &dev->subdevices[cmd.subdev];
1791 /* are we locked? (ioctl lock) */
1792 if (s->lock && s->lock != file) {
1793 dev_dbg(dev->class_dev, "subdevice locked\n");
1799 dev_dbg(dev->class_dev, "subdevice busy\n");
1803 /* make sure channel/gain list isn't too short */
1804 if (cmd.chanlist_len < 1) {
1805 dev_dbg(dev->class_dev, "channel/gain list too short %u < 1\n",
1811 async->cmd.data = NULL;
1813 /* load channel/gain list */
1814 ret = __comedi_get_user_chanlist(dev, s, user_chanlist, &async->cmd);
1818 ret = s->do_cmdtest(dev, s, &async->cmd);
1820 if (async->cmd.flags & CMDF_BOGUS || ret) {
1821 dev_dbg(dev->class_dev, "test returned %d\n", ret);
1823 /* restore chanlist pointer before copying back */
1824 cmd.chanlist = (unsigned int __force *)user_chanlist;
1826 if (copy_to_user(arg, &cmd, sizeof(cmd))) {
1827 dev_dbg(dev->class_dev, "fault writing cmd\n");
1835 if (!async->prealloc_bufsz) {
1837 dev_dbg(dev->class_dev, "no buffer (?)\n");
1841 comedi_buf_reset(s);
1843 async->cb_mask = COMEDI_CB_BLOCK | COMEDI_CB_CANCEL_MASK;
1844 if (async->cmd.flags & CMDF_WAKE_EOS)
1845 async->cb_mask |= COMEDI_CB_EOS;
1847 comedi_update_subdevice_runflags(s, COMEDI_SRF_BUSY_MASK,
1848 COMEDI_SRF_RUNNING);
1851 * Set s->busy _after_ setting COMEDI_SRF_RUNNING flag to avoid
1852 * race with comedi_read() or comedi_write().
1855 ret = s->do_cmd(dev, s);
1860 do_become_nonbusy(dev, s);
1866 * COMEDI_CMDTEST ioctl
1867 * asynchronous acquisition command testing
1870 * pointer to comedi_cmd structure
1873 * comedi_cmd structure
1874 * channel/range list from cmd->chanlist pointer
1877 * possibly modified comedi_cmd structure
1879 static int do_cmdtest_ioctl(struct comedi_device *dev,
1880 struct comedi_cmd __user *arg, void *file)
1882 struct comedi_cmd cmd;
1883 struct comedi_subdevice *s;
1884 unsigned int __user *user_chanlist;
1887 lockdep_assert_held(&dev->mutex);
1889 /* get the user's cmd and do some simple validation */
1890 ret = __comedi_get_user_cmd(dev, arg, &cmd);
1894 /* save user's chanlist pointer so it can be restored later */
1895 user_chanlist = (unsigned int __user *)cmd.chanlist;
1897 s = &dev->subdevices[cmd.subdev];
1899 /* user_chanlist can be NULL for COMEDI_CMDTEST ioctl */
1900 if (user_chanlist) {
1901 /* load channel/gain list */
1902 ret = __comedi_get_user_chanlist(dev, s, user_chanlist, &cmd);
1907 ret = s->do_cmdtest(dev, s, &cmd);
1909 kfree(cmd.chanlist); /* free kernel copy of user chanlist */
1911 /* restore chanlist pointer before copying back */
1912 cmd.chanlist = (unsigned int __force *)user_chanlist;
1914 if (copy_to_user(arg, &cmd, sizeof(cmd))) {
1915 dev_dbg(dev->class_dev, "bad cmd address\n");
1935 static int do_lock_ioctl(struct comedi_device *dev, unsigned long arg,
1939 unsigned long flags;
1940 struct comedi_subdevice *s;
1942 lockdep_assert_held(&dev->mutex);
1943 if (arg >= dev->n_subdevices)
1945 s = &dev->subdevices[arg];
1947 spin_lock_irqsave(&s->spin_lock, flags);
1948 if (s->busy || s->lock)
1952 spin_unlock_irqrestore(&s->spin_lock, flags);
1958 * COMEDI_UNLOCK ioctl
1970 static int do_unlock_ioctl(struct comedi_device *dev, unsigned long arg,
1973 struct comedi_subdevice *s;
1975 lockdep_assert_held(&dev->mutex);
1976 if (arg >= dev->n_subdevices)
1978 s = &dev->subdevices[arg];
1983 if (s->lock && s->lock != file)
1986 if (s->lock == file)
1993 * COMEDI_CANCEL ioctl
1994 * cancel asynchronous acquisition
2005 static int do_cancel_ioctl(struct comedi_device *dev, unsigned long arg,
2008 struct comedi_subdevice *s;
2010 lockdep_assert_held(&dev->mutex);
2011 if (arg >= dev->n_subdevices)
2013 s = &dev->subdevices[arg];
2020 if (s->busy != file)
2023 return do_cancel(dev, s);
2028 * instructs driver to synchronize buffers
2039 static int do_poll_ioctl(struct comedi_device *dev, unsigned long arg,
2042 struct comedi_subdevice *s;
2044 lockdep_assert_held(&dev->mutex);
2045 if (arg >= dev->n_subdevices)
2047 s = &dev->subdevices[arg];
2052 if (s->busy != file)
2056 return s->poll(dev, s);
2062 * COMEDI_SETRSUBD ioctl
2063 * sets the current "read" subdevice on a per-file basis
2074 static int do_setrsubd_ioctl(struct comedi_device *dev, unsigned long arg,
2077 struct comedi_file *cfp = file->private_data;
2078 struct comedi_subdevice *s_old, *s_new;
2080 lockdep_assert_held(&dev->mutex);
2081 if (arg >= dev->n_subdevices)
2084 s_new = &dev->subdevices[arg];
2085 s_old = comedi_file_read_subdevice(file);
2087 return 0; /* no change */
2089 if (!(s_new->subdev_flags & SDF_CMD_READ))
2093 * Check the file isn't still busy handling a "read" command on the
2094 * old subdevice (if any).
2096 if (s_old && s_old->busy == file && s_old->async &&
2097 !(s_old->async->cmd.flags & CMDF_WRITE))
2100 WRITE_ONCE(cfp->read_subdev, s_new);
2105 * COMEDI_SETWSUBD ioctl
2106 * sets the current "write" subdevice on a per-file basis
2117 static int do_setwsubd_ioctl(struct comedi_device *dev, unsigned long arg,
2120 struct comedi_file *cfp = file->private_data;
2121 struct comedi_subdevice *s_old, *s_new;
2123 lockdep_assert_held(&dev->mutex);
2124 if (arg >= dev->n_subdevices)
2127 s_new = &dev->subdevices[arg];
2128 s_old = comedi_file_write_subdevice(file);
2130 return 0; /* no change */
2132 if (!(s_new->subdev_flags & SDF_CMD_WRITE))
2136 * Check the file isn't still busy handling a "write" command on the
2137 * old subdevice (if any).
2139 if (s_old && s_old->busy == file && s_old->async &&
2140 (s_old->async->cmd.flags & CMDF_WRITE))
2143 WRITE_ONCE(cfp->write_subdev, s_new);
2147 static long comedi_unlocked_ioctl(struct file *file, unsigned int cmd,
2150 unsigned int minor = iminor(file_inode(file));
2151 struct comedi_file *cfp = file->private_data;
2152 struct comedi_device *dev = cfp->dev;
2155 mutex_lock(&dev->mutex);
2158 * Device config is special, because it must work on
2159 * an unconfigured device.
2161 if (cmd == COMEDI_DEVCONFIG) {
2162 if (minor >= COMEDI_NUM_BOARD_MINORS) {
2163 /* Device config not appropriate on non-board minors. */
2167 rc = do_devconfig_ioctl(dev,
2168 (struct comedi_devconfig __user *)arg);
2171 dev->minor >= comedi_num_legacy_minors) {
2173 * Successfully unconfigured a dynamically
2174 * allocated device. Try and remove it.
2176 if (comedi_clear_board_dev(dev)) {
2177 mutex_unlock(&dev->mutex);
2178 comedi_free_board_dev(dev);
2186 if (!dev->attached) {
2187 dev_dbg(dev->class_dev, "no driver attached\n");
2193 case COMEDI_BUFCONFIG:
2194 rc = do_bufconfig_ioctl(dev,
2195 (struct comedi_bufconfig __user *)arg);
2197 case COMEDI_DEVINFO:
2198 rc = do_devinfo_ioctl(dev, (struct comedi_devinfo __user *)arg,
2201 case COMEDI_SUBDINFO:
2202 rc = do_subdinfo_ioctl(dev,
2203 (struct comedi_subdinfo __user *)arg,
2206 case COMEDI_CHANINFO:
2207 rc = do_chaninfo_ioctl(dev, (void __user *)arg);
2209 case COMEDI_RANGEINFO:
2210 rc = do_rangeinfo_ioctl(dev, (void __user *)arg);
2212 case COMEDI_BUFINFO:
2213 rc = do_bufinfo_ioctl(dev,
2214 (struct comedi_bufinfo __user *)arg,
2218 rc = do_lock_ioctl(dev, arg, file);
2221 rc = do_unlock_ioctl(dev, arg, file);
2224 rc = do_cancel_ioctl(dev, arg, file);
2227 rc = do_cmd_ioctl(dev, (struct comedi_cmd __user *)arg, file);
2229 case COMEDI_CMDTEST:
2230 rc = do_cmdtest_ioctl(dev, (struct comedi_cmd __user *)arg,
2233 case COMEDI_INSNLIST:
2234 rc = do_insnlist_ioctl(dev,
2235 (struct comedi_insnlist __user *)arg,
2239 rc = do_insn_ioctl(dev, (struct comedi_insn __user *)arg,
2243 rc = do_poll_ioctl(dev, arg, file);
2245 case COMEDI_SETRSUBD:
2246 rc = do_setrsubd_ioctl(dev, arg, file);
2248 case COMEDI_SETWSUBD:
2249 rc = do_setwsubd_ioctl(dev, arg, file);
2257 mutex_unlock(&dev->mutex);
2261 static void comedi_vm_open(struct vm_area_struct *area)
2263 struct comedi_buf_map *bm;
2265 bm = area->vm_private_data;
2266 comedi_buf_map_get(bm);
2269 static void comedi_vm_close(struct vm_area_struct *area)
2271 struct comedi_buf_map *bm;
2273 bm = area->vm_private_data;
2274 comedi_buf_map_put(bm);
2277 static int comedi_vm_access(struct vm_area_struct *vma, unsigned long addr,
2278 void *buf, int len, int write)
2280 struct comedi_buf_map *bm = vma->vm_private_data;
2281 unsigned long offset =
2282 addr - vma->vm_start + (vma->vm_pgoff << PAGE_SHIFT);
2286 if (len > vma->vm_end - addr)
2287 len = vma->vm_end - addr;
2288 return comedi_buf_map_access(bm, offset, buf, len, write);
2291 static const struct vm_operations_struct comedi_vm_ops = {
2292 .open = comedi_vm_open,
2293 .close = comedi_vm_close,
2294 .access = comedi_vm_access,
2297 static int comedi_mmap(struct file *file, struct vm_area_struct *vma)
2299 struct comedi_file *cfp = file->private_data;
2300 struct comedi_device *dev = cfp->dev;
2301 struct comedi_subdevice *s;
2302 struct comedi_async *async;
2303 struct comedi_buf_map *bm = NULL;
2304 struct comedi_buf_page *buf;
2305 unsigned long start = vma->vm_start;
2312 * 'trylock' avoids circular dependency with current->mm->mmap_sem
2313 * and down-reading &dev->attach_lock should normally succeed without
2314 * contention unless the device is in the process of being attached
2317 if (!down_read_trylock(&dev->attach_lock))
2320 if (!dev->attached) {
2321 dev_dbg(dev->class_dev, "no driver attached\n");
2326 if (vma->vm_flags & VM_WRITE)
2327 s = comedi_file_write_subdevice(file);
2329 s = comedi_file_read_subdevice(file);
2341 if (vma->vm_pgoff != 0) {
2342 dev_dbg(dev->class_dev, "mmap() offset must be 0.\n");
2347 size = vma->vm_end - vma->vm_start;
2348 if (size > async->prealloc_bufsz) {
2352 if (offset_in_page(size)) {
2357 n_pages = vma_pages(vma);
2359 /* get reference to current buf map (if any) */
2360 bm = comedi_buf_map_from_subdev_get(s);
2361 if (!bm || n_pages > bm->n_pages) {
2365 if (bm->dma_dir != DMA_NONE) {
2367 * DMA buffer was allocated as a single block.
2368 * Address is in page_list[0].
2370 buf = &bm->page_list[0];
2371 retval = dma_mmap_coherent(bm->dma_hw_dev, vma, buf->virt_addr,
2372 buf->dma_addr, n_pages * PAGE_SIZE);
2374 for (i = 0; i < n_pages; ++i) {
2377 buf = &bm->page_list[i];
2378 pfn = page_to_pfn(virt_to_page(buf->virt_addr));
2379 retval = remap_pfn_range(vma, start, pfn, PAGE_SIZE,
2389 vma->vm_ops = &comedi_vm_ops;
2390 vma->vm_private_data = bm;
2392 vma->vm_ops->open(vma);
2396 up_read(&dev->attach_lock);
2397 comedi_buf_map_put(bm); /* put reference to buf map - okay if NULL */
2401 static __poll_t comedi_poll(struct file *file, poll_table *wait)
2404 struct comedi_file *cfp = file->private_data;
2405 struct comedi_device *dev = cfp->dev;
2406 struct comedi_subdevice *s, *s_read;
2408 down_read(&dev->attach_lock);
2410 if (!dev->attached) {
2411 dev_dbg(dev->class_dev, "no driver attached\n");
2415 s = comedi_file_read_subdevice(file);
2417 if (s && s->async) {
2418 poll_wait(file, &s->async->wait_head, wait);
2419 if (s->busy != file || !comedi_is_subdevice_running(s) ||
2420 (s->async->cmd.flags & CMDF_WRITE) ||
2421 comedi_buf_read_n_available(s) > 0)
2422 mask |= EPOLLIN | EPOLLRDNORM;
2425 s = comedi_file_write_subdevice(file);
2426 if (s && s->async) {
2427 unsigned int bps = comedi_bytes_per_sample(s);
2430 poll_wait(file, &s->async->wait_head, wait);
2431 if (s->busy != file || !comedi_is_subdevice_running(s) ||
2432 !(s->async->cmd.flags & CMDF_WRITE) ||
2433 comedi_buf_write_n_available(s) >= bps)
2434 mask |= EPOLLOUT | EPOLLWRNORM;
2438 up_read(&dev->attach_lock);
2442 static ssize_t comedi_write(struct file *file, const char __user *buf,
2443 size_t nbytes, loff_t *offset)
2445 struct comedi_subdevice *s;
2446 struct comedi_async *async;
2450 DECLARE_WAITQUEUE(wait, current);
2451 struct comedi_file *cfp = file->private_data;
2452 struct comedi_device *dev = cfp->dev;
2453 bool become_nonbusy = false;
2455 unsigned int old_detach_count;
2457 /* Protect against device detachment during operation. */
2458 down_read(&dev->attach_lock);
2459 attach_locked = true;
2460 old_detach_count = dev->detach_count;
2462 if (!dev->attached) {
2463 dev_dbg(dev->class_dev, "no driver attached\n");
2468 s = comedi_file_write_subdevice(file);
2469 if (!s || !s->async) {
2475 if (s->busy != file || !(async->cmd.flags & CMDF_WRITE)) {
2480 add_wait_queue(&async->wait_head, &wait);
2481 while (count == 0 && !retval) {
2482 unsigned int runflags;
2483 unsigned int wp, n1, n2;
2485 set_current_state(TASK_INTERRUPTIBLE);
2487 runflags = comedi_get_subdevice_runflags(s);
2488 if (!comedi_is_runflags_running(runflags)) {
2489 if (comedi_is_runflags_in_error(runflags))
2491 if (retval || nbytes)
2492 become_nonbusy = true;
2498 /* Allocate all free buffer space. */
2499 comedi_buf_write_alloc(s, async->prealloc_bufsz);
2500 m = comedi_buf_write_n_allocated(s);
2501 n = min_t(size_t, m, nbytes);
2504 if (file->f_flags & O_NONBLOCK) {
2509 if (signal_pending(current)) {
2510 retval = -ERESTARTSYS;
2513 if (s->busy != file ||
2514 !(async->cmd.flags & CMDF_WRITE)) {
2521 set_current_state(TASK_RUNNING);
2522 wp = async->buf_write_ptr;
2523 n1 = min(n, async->prealloc_bufsz - wp);
2525 m = copy_from_user(async->prealloc_buf + wp, buf, n1);
2529 m = copy_from_user(async->prealloc_buf, buf + n1, n2);
2534 comedi_buf_write_free(s, n);
2541 remove_wait_queue(&async->wait_head, &wait);
2542 set_current_state(TASK_RUNNING);
2543 if (become_nonbusy && count == 0) {
2544 struct comedi_subdevice *new_s;
2547 * To avoid deadlock, cannot acquire dev->mutex
2548 * while dev->attach_lock is held.
2550 up_read(&dev->attach_lock);
2551 attach_locked = false;
2552 mutex_lock(&dev->mutex);
2554 * Check device hasn't become detached behind our back.
2555 * Checking dev->detach_count is unchanged ought to be
2556 * sufficient (unless there have been 2**32 detaches in the
2557 * meantime!), but check the subdevice pointer as well just in
2560 * Also check the subdevice is still in a suitable state to
2561 * become non-busy in case it changed behind our back.
2563 new_s = comedi_file_write_subdevice(file);
2564 if (dev->attached && old_detach_count == dev->detach_count &&
2565 s == new_s && new_s->async == async && s->busy == file &&
2566 (async->cmd.flags & CMDF_WRITE) &&
2567 !comedi_is_subdevice_running(s))
2568 do_become_nonbusy(dev, s);
2569 mutex_unlock(&dev->mutex);
2573 up_read(&dev->attach_lock);
2575 return count ? count : retval;
2578 static ssize_t comedi_read(struct file *file, char __user *buf, size_t nbytes,
2581 struct comedi_subdevice *s;
2582 struct comedi_async *async;
2586 DECLARE_WAITQUEUE(wait, current);
2587 struct comedi_file *cfp = file->private_data;
2588 struct comedi_device *dev = cfp->dev;
2589 unsigned int old_detach_count;
2590 bool become_nonbusy = false;
2593 /* Protect against device detachment during operation. */
2594 down_read(&dev->attach_lock);
2595 attach_locked = true;
2596 old_detach_count = dev->detach_count;
2598 if (!dev->attached) {
2599 dev_dbg(dev->class_dev, "no driver attached\n");
2604 s = comedi_file_read_subdevice(file);
2605 if (!s || !s->async) {
2611 if (s->busy != file || (async->cmd.flags & CMDF_WRITE)) {
2616 add_wait_queue(&async->wait_head, &wait);
2617 while (count == 0 && !retval) {
2618 unsigned int rp, n1, n2;
2620 set_current_state(TASK_INTERRUPTIBLE);
2622 m = comedi_buf_read_n_available(s);
2623 n = min_t(size_t, m, nbytes);
2626 unsigned int runflags =
2627 comedi_get_subdevice_runflags(s);
2629 if (!comedi_is_runflags_running(runflags)) {
2630 if (comedi_is_runflags_in_error(runflags))
2632 if (retval || nbytes)
2633 become_nonbusy = true;
2638 if (file->f_flags & O_NONBLOCK) {
2643 if (signal_pending(current)) {
2644 retval = -ERESTARTSYS;
2647 if (s->busy != file ||
2648 (async->cmd.flags & CMDF_WRITE)) {
2655 set_current_state(TASK_RUNNING);
2656 rp = async->buf_read_ptr;
2657 n1 = min(n, async->prealloc_bufsz - rp);
2659 m = copy_to_user(buf, async->prealloc_buf + rp, n1);
2663 m = copy_to_user(buf + n1, async->prealloc_buf, n2);
2669 comedi_buf_read_alloc(s, n);
2670 comedi_buf_read_free(s, n);
2677 remove_wait_queue(&async->wait_head, &wait);
2678 set_current_state(TASK_RUNNING);
2679 if (become_nonbusy && count == 0) {
2680 struct comedi_subdevice *new_s;
2683 * To avoid deadlock, cannot acquire dev->mutex
2684 * while dev->attach_lock is held.
2686 up_read(&dev->attach_lock);
2687 attach_locked = false;
2688 mutex_lock(&dev->mutex);
2690 * Check device hasn't become detached behind our back.
2691 * Checking dev->detach_count is unchanged ought to be
2692 * sufficient (unless there have been 2**32 detaches in the
2693 * meantime!), but check the subdevice pointer as well just in
2696 * Also check the subdevice is still in a suitable state to
2697 * become non-busy in case it changed behind our back.
2699 new_s = comedi_file_read_subdevice(file);
2700 if (dev->attached && old_detach_count == dev->detach_count &&
2701 s == new_s && new_s->async == async && s->busy == file &&
2702 !(async->cmd.flags & CMDF_WRITE) &&
2703 !comedi_is_subdevice_running(s) &&
2704 comedi_buf_read_n_available(s) == 0)
2705 do_become_nonbusy(dev, s);
2706 mutex_unlock(&dev->mutex);
2710 up_read(&dev->attach_lock);
2712 return count ? count : retval;
2715 static int comedi_open(struct inode *inode, struct file *file)
2717 const unsigned int minor = iminor(inode);
2718 struct comedi_file *cfp;
2719 struct comedi_device *dev = comedi_dev_get_from_minor(minor);
2723 pr_debug("invalid minor number\n");
2727 cfp = kzalloc(sizeof(*cfp), GFP_KERNEL);
2729 comedi_dev_put(dev);
2735 mutex_lock(&dev->mutex);
2736 if (!dev->attached && !capable(CAP_SYS_ADMIN)) {
2737 dev_dbg(dev->class_dev, "not attached and not CAP_SYS_ADMIN\n");
2741 if (dev->attached && dev->use_count == 0) {
2742 if (!try_module_get(dev->driver->module)) {
2747 rc = dev->open(dev);
2749 module_put(dev->driver->module);
2756 file->private_data = cfp;
2757 comedi_file_reset(file);
2761 mutex_unlock(&dev->mutex);
2763 comedi_dev_put(dev);
2769 static int comedi_fasync(int fd, struct file *file, int on)
2771 struct comedi_file *cfp = file->private_data;
2772 struct comedi_device *dev = cfp->dev;
2774 return fasync_helper(fd, file, on, &dev->async_queue);
2777 static int comedi_close(struct inode *inode, struct file *file)
2779 struct comedi_file *cfp = file->private_data;
2780 struct comedi_device *dev = cfp->dev;
2781 struct comedi_subdevice *s = NULL;
2784 mutex_lock(&dev->mutex);
2786 if (dev->subdevices) {
2787 for (i = 0; i < dev->n_subdevices; i++) {
2788 s = &dev->subdevices[i];
2790 if (s->busy == file)
2792 if (s->lock == file)
2796 if (dev->attached && dev->use_count == 1) {
2799 module_put(dev->driver->module);
2804 mutex_unlock(&dev->mutex);
2805 comedi_dev_put(dev);
2811 static const struct file_operations comedi_fops = {
2812 .owner = THIS_MODULE,
2813 .unlocked_ioctl = comedi_unlocked_ioctl,
2814 .compat_ioctl = comedi_compat_ioctl,
2815 .open = comedi_open,
2816 .release = comedi_close,
2817 .read = comedi_read,
2818 .write = comedi_write,
2819 .mmap = comedi_mmap,
2820 .poll = comedi_poll,
2821 .fasync = comedi_fasync,
2822 .llseek = noop_llseek,
2826 * comedi_event() - Handle events for asynchronous COMEDI command
2827 * @dev: COMEDI device.
2828 * @s: COMEDI subdevice.
2829 * Context: in_interrupt() (usually), @s->spin_lock spin-lock not held.
2831 * If an asynchronous COMEDI command is active on the subdevice, process
2832 * any %COMEDI_CB_... event flags that have been set, usually by an
2833 * interrupt handler. These may change the run state of the asynchronous
2834 * command, wake a task, and/or send a %SIGIO signal.
2836 void comedi_event(struct comedi_device *dev, struct comedi_subdevice *s)
2838 struct comedi_async *async = s->async;
2839 unsigned int events;
2841 unsigned long flags;
2843 spin_lock_irqsave(&s->spin_lock, flags);
2845 events = async->events;
2847 if (!__comedi_is_subdevice_running(s)) {
2848 spin_unlock_irqrestore(&s->spin_lock, flags);
2852 if (events & COMEDI_CB_CANCEL_MASK)
2853 __comedi_clear_subdevice_runflags(s, COMEDI_SRF_RUNNING);
2856 * Remember if an error event has occurred, so an error can be
2857 * returned the next time the user does a read() or write().
2859 if (events & COMEDI_CB_ERROR_MASK)
2860 __comedi_set_subdevice_runflags(s, COMEDI_SRF_ERROR);
2862 if (async->cb_mask & events) {
2863 wake_up_interruptible(&async->wait_head);
2864 si_code = async->cmd.flags & CMDF_WRITE ? POLL_OUT : POLL_IN;
2867 spin_unlock_irqrestore(&s->spin_lock, flags);
2870 kill_fasync(&dev->async_queue, SIGIO, si_code);
2872 EXPORT_SYMBOL_GPL(comedi_event);
2874 /* Note: the ->mutex is pre-locked on successful return */
2875 struct comedi_device *comedi_alloc_board_minor(struct device *hardware_device)
2877 struct comedi_device *dev;
2878 struct device *csdev;
2881 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
2883 return ERR_PTR(-ENOMEM);
2884 comedi_device_init(dev);
2885 comedi_set_hw_dev(dev, hardware_device);
2886 mutex_lock(&dev->mutex);
2887 mutex_lock(&comedi_board_minor_table_lock);
2888 for (i = hardware_device ? comedi_num_legacy_minors : 0;
2889 i < COMEDI_NUM_BOARD_MINORS; ++i) {
2890 if (!comedi_board_minor_table[i]) {
2891 comedi_board_minor_table[i] = dev;
2895 mutex_unlock(&comedi_board_minor_table_lock);
2896 if (i == COMEDI_NUM_BOARD_MINORS) {
2897 mutex_unlock(&dev->mutex);
2898 comedi_device_cleanup(dev);
2899 comedi_dev_put(dev);
2900 dev_err(hardware_device,
2901 "ran out of minor numbers for board device files\n");
2902 return ERR_PTR(-EBUSY);
2905 csdev = device_create(comedi_class, hardware_device,
2906 MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i", i);
2908 dev->class_dev = get_device(csdev);
2910 /* Note: dev->mutex needs to be unlocked by the caller. */
2914 void comedi_release_hardware_device(struct device *hardware_device)
2917 struct comedi_device *dev;
2919 for (minor = comedi_num_legacy_minors; minor < COMEDI_NUM_BOARD_MINORS;
2921 mutex_lock(&comedi_board_minor_table_lock);
2922 dev = comedi_board_minor_table[minor];
2923 if (dev && dev->hw_dev == hardware_device) {
2924 comedi_board_minor_table[minor] = NULL;
2925 mutex_unlock(&comedi_board_minor_table_lock);
2926 comedi_free_board_dev(dev);
2929 mutex_unlock(&comedi_board_minor_table_lock);
2933 int comedi_alloc_subdevice_minor(struct comedi_subdevice *s)
2935 struct comedi_device *dev = s->device;
2936 struct device *csdev;
2939 mutex_lock(&comedi_subdevice_minor_table_lock);
2940 for (i = 0; i < COMEDI_NUM_SUBDEVICE_MINORS; ++i) {
2941 if (!comedi_subdevice_minor_table[i]) {
2942 comedi_subdevice_minor_table[i] = s;
2946 mutex_unlock(&comedi_subdevice_minor_table_lock);
2947 if (i == COMEDI_NUM_SUBDEVICE_MINORS) {
2948 dev_err(dev->class_dev,
2949 "ran out of minor numbers for subdevice files\n");
2952 i += COMEDI_NUM_BOARD_MINORS;
2954 csdev = device_create(comedi_class, dev->class_dev,
2955 MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i_subd%i",
2956 dev->minor, s->index);
2958 s->class_dev = csdev;
2963 void comedi_free_subdevice_minor(struct comedi_subdevice *s)
2969 if (s->minor < COMEDI_NUM_BOARD_MINORS ||
2970 s->minor >= COMEDI_NUM_MINORS)
2973 i = s->minor - COMEDI_NUM_BOARD_MINORS;
2974 mutex_lock(&comedi_subdevice_minor_table_lock);
2975 if (s == comedi_subdevice_minor_table[i])
2976 comedi_subdevice_minor_table[i] = NULL;
2977 mutex_unlock(&comedi_subdevice_minor_table_lock);
2979 device_destroy(comedi_class, MKDEV(COMEDI_MAJOR, s->minor));
2980 s->class_dev = NULL;
2984 static void comedi_cleanup_board_minors(void)
2986 struct comedi_device *dev;
2989 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) {
2990 dev = comedi_clear_board_minor(i);
2991 comedi_free_board_dev(dev);
2995 static int __init comedi_init(void)
3000 pr_info("version " COMEDI_RELEASE " - http://www.comedi.org\n");
3002 if (comedi_num_legacy_minors > COMEDI_NUM_BOARD_MINORS) {
3003 pr_err("invalid value for module parameter \"comedi_num_legacy_minors\". Valid values are 0 through %i.\n",
3004 COMEDI_NUM_BOARD_MINORS);
3008 retval = register_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
3009 COMEDI_NUM_MINORS, "comedi");
3013 cdev_init(&comedi_cdev, &comedi_fops);
3014 comedi_cdev.owner = THIS_MODULE;
3016 retval = kobject_set_name(&comedi_cdev.kobj, "comedi");
3018 goto out_unregister_chrdev_region;
3020 retval = cdev_add(&comedi_cdev, MKDEV(COMEDI_MAJOR, 0),
3023 goto out_unregister_chrdev_region;
3025 comedi_class = class_create(THIS_MODULE, "comedi");
3026 if (IS_ERR(comedi_class)) {
3027 retval = PTR_ERR(comedi_class);
3028 pr_err("failed to create class\n");
3032 comedi_class->dev_groups = comedi_dev_groups;
3034 /* create devices files for legacy/manual use */
3035 for (i = 0; i < comedi_num_legacy_minors; i++) {
3036 struct comedi_device *dev;
3038 dev = comedi_alloc_board_minor(NULL);
3040 retval = PTR_ERR(dev);
3041 goto out_cleanup_board_minors;
3043 /* comedi_alloc_board_minor() locked the mutex */
3044 lockdep_assert_held(&dev->mutex);
3045 mutex_unlock(&dev->mutex);
3048 /* XXX requires /proc interface */
3053 out_cleanup_board_minors:
3054 comedi_cleanup_board_minors();
3055 class_destroy(comedi_class);
3057 cdev_del(&comedi_cdev);
3058 out_unregister_chrdev_region:
3059 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS);
3062 module_init(comedi_init);
3064 static void __exit comedi_cleanup(void)
3066 comedi_cleanup_board_minors();
3067 class_destroy(comedi_class);
3068 cdev_del(&comedi_cdev);
3069 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS);
3071 comedi_proc_cleanup();
3073 module_exit(comedi_cleanup);
3075 MODULE_AUTHOR("http://www.comedi.org");
3076 MODULE_DESCRIPTION("Comedi core module");
3077 MODULE_LICENSE("GPL");