3 functions for manipulating drivers
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 #include <linux/device.h>
20 #include <linux/module.h>
21 #include <linux/errno.h>
22 #include <linux/kconfig.h>
23 #include <linux/kernel.h>
24 #include <linux/sched.h>
25 #include <linux/fcntl.h>
26 #include <linux/ioport.h>
28 #include <linux/slab.h>
29 #include <linux/highmem.h> /* for SuSE brokenness */
30 #include <linux/vmalloc.h>
31 #include <linux/cdev.h>
32 #include <linux/dma-mapping.h>
34 #include <linux/interrupt.h>
35 #include <linux/firmware.h>
37 #include "comedidev.h"
38 #include "comedi_internal.h"
40 struct comedi_driver *comedi_drivers;
41 /* protects access to comedi_drivers */
42 DEFINE_MUTEX(comedi_drivers_list_lock);
44 int comedi_set_hw_dev(struct comedi_device *dev, struct device *hw_dev)
46 if (hw_dev == dev->hw_dev)
48 if (dev->hw_dev != NULL)
50 dev->hw_dev = get_device(hw_dev);
53 EXPORT_SYMBOL_GPL(comedi_set_hw_dev);
55 static void comedi_clear_hw_dev(struct comedi_device *dev)
57 put_device(dev->hw_dev);
62 * comedi_alloc_devpriv() - Allocate memory for the device private data.
63 * @dev: comedi_device struct
64 * @size: size of the memory to allocate
66 void *comedi_alloc_devpriv(struct comedi_device *dev, size_t size)
68 dev->private = kzalloc(size, GFP_KERNEL);
71 EXPORT_SYMBOL_GPL(comedi_alloc_devpriv);
73 int comedi_alloc_subdevices(struct comedi_device *dev, int num_subdevices)
75 struct comedi_subdevice *s;
78 if (num_subdevices < 1)
81 s = kcalloc(num_subdevices, sizeof(*s), GFP_KERNEL);
85 dev->n_subdevices = num_subdevices;
87 for (i = 0; i < num_subdevices; ++i) {
88 s = &dev->subdevices[i];
91 s->async_dma_dir = DMA_NONE;
92 spin_lock_init(&s->spin_lock);
97 EXPORT_SYMBOL_GPL(comedi_alloc_subdevices);
99 static void comedi_device_detach_cleanup(struct comedi_device *dev)
102 struct comedi_subdevice *s;
104 if (dev->subdevices) {
105 for (i = 0; i < dev->n_subdevices; i++) {
106 s = &dev->subdevices[i];
107 if (s->runflags & SRF_FREE_SPRIV)
109 comedi_free_subdevice_minor(s);
111 comedi_buf_alloc(dev, s, 0);
115 kfree(dev->subdevices);
116 dev->subdevices = NULL;
117 dev->n_subdevices = 0;
122 dev->board_name = NULL;
123 dev->board_ptr = NULL;
126 dev->ioenabled = false;
128 dev->read_subdev = NULL;
129 dev->write_subdev = NULL;
132 comedi_clear_hw_dev(dev);
135 void comedi_device_detach(struct comedi_device *dev)
137 comedi_device_cancel_all(dev);
138 down_write(&dev->attach_lock);
139 dev->attached = false;
142 dev->driver->detach(dev);
143 comedi_device_detach_cleanup(dev);
144 up_write(&dev->attach_lock);
147 static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s)
152 int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s,
153 struct comedi_insn *insn, unsigned int *data)
159 * comedi_timeout() - busy-wait for a driver condition to occur.
160 * @dev: comedi_device struct
161 * @s: comedi_subdevice struct
162 * @insn: comedi_insn struct
163 * @cb: callback to check for the condition
164 * @context: private context from the driver
166 int comedi_timeout(struct comedi_device *dev,
167 struct comedi_subdevice *s,
168 struct comedi_insn *insn,
169 int (*cb)(struct comedi_device *dev,
170 struct comedi_subdevice *s,
171 struct comedi_insn *insn,
172 unsigned long context),
173 unsigned long context)
175 unsigned long timeout = jiffies + msecs_to_jiffies(COMEDI_TIMEOUT_MS);
178 while (time_before(jiffies, timeout)) {
179 ret = cb(dev, s, insn, context);
181 return ret; /* success (0) or non EBUSY errno */
186 EXPORT_SYMBOL_GPL(comedi_timeout);
189 * comedi_dio_insn_config() - boilerplate (*insn_config) for DIO subdevices.
190 * @dev: comedi_device struct
191 * @s: comedi_subdevice struct
192 * @insn: comedi_insn struct
193 * @data: parameters for the @insn
194 * @mask: io_bits mask for grouped channels
196 int comedi_dio_insn_config(struct comedi_device *dev,
197 struct comedi_subdevice *s,
198 struct comedi_insn *insn,
202 unsigned int chan_mask = 1 << CR_CHAN(insn->chanspec);
208 case INSN_CONFIG_DIO_INPUT:
212 case INSN_CONFIG_DIO_OUTPUT:
216 case INSN_CONFIG_DIO_QUERY:
217 data[1] = (s->io_bits & mask) ? COMEDI_OUTPUT : COMEDI_INPUT;
226 EXPORT_SYMBOL_GPL(comedi_dio_insn_config);
229 * comedi_dio_update_state() - update the internal state of DIO subdevices.
230 * @s: comedi_subdevice struct
231 * @data: the channel mask and bits to update
233 unsigned int comedi_dio_update_state(struct comedi_subdevice *s,
236 unsigned int chanmask = (s->n_chan < 32) ? ((1 << s->n_chan) - 1)
238 unsigned int mask = data[0] & chanmask;
239 unsigned int bits = data[1];
243 s->state |= (bits & mask);
248 EXPORT_SYMBOL_GPL(comedi_dio_update_state);
250 static int insn_rw_emulate_bits(struct comedi_device *dev,
251 struct comedi_subdevice *s,
252 struct comedi_insn *insn, unsigned int *data)
254 struct comedi_insn new_insn;
256 static const unsigned channels_per_bitfield = 32;
258 unsigned chan = CR_CHAN(insn->chanspec);
259 const unsigned base_bitfield_channel =
260 (chan < channels_per_bitfield) ? 0 : chan;
261 unsigned int new_data[2];
263 memset(new_data, 0, sizeof(new_data));
264 memset(&new_insn, 0, sizeof(new_insn));
265 new_insn.insn = INSN_BITS;
266 new_insn.chanspec = base_bitfield_channel;
268 new_insn.subdev = insn->subdev;
270 if (insn->insn == INSN_WRITE) {
271 if (!(s->subdev_flags & SDF_WRITABLE))
273 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */
274 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel))
278 ret = s->insn_bits(dev, s, &new_insn, new_data);
282 if (insn->insn == INSN_READ)
283 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1;
288 static int __comedi_device_postconfig_async(struct comedi_device *dev,
289 struct comedi_subdevice *s)
291 struct comedi_async *async;
292 unsigned int buf_size;
295 if ((s->subdev_flags & (SDF_CMD_READ | SDF_CMD_WRITE)) == 0) {
296 dev_warn(dev->class_dev,
297 "async subdevices must support SDF_CMD_READ or SDF_CMD_WRITE\n");
300 if (!s->do_cmdtest) {
301 dev_warn(dev->class_dev,
302 "async subdevices must have a do_cmdtest() function\n");
306 async = kzalloc(sizeof(*async), GFP_KERNEL);
310 init_waitqueue_head(&async->wait_head);
313 async->max_bufsize = comedi_default_buf_maxsize_kb * 1024;
314 buf_size = comedi_default_buf_size_kb * 1024;
315 if (buf_size > async->max_bufsize)
316 buf_size = async->max_bufsize;
318 if (comedi_buf_alloc(dev, s, buf_size) < 0) {
319 dev_warn(dev->class_dev, "Buffer allocation failed\n");
323 ret = s->buf_change(dev, s);
328 comedi_alloc_subdevice_minor(s);
333 static int __comedi_device_postconfig(struct comedi_device *dev)
335 struct comedi_subdevice *s;
339 for (i = 0; i < dev->n_subdevices; i++) {
340 s = &dev->subdevices[i];
342 if (s->type == COMEDI_SUBD_UNUSED)
345 if (s->type == COMEDI_SUBD_DO) {
347 s->io_bits = (1 << s->n_chan) - 1;
349 s->io_bits = 0xffffffff;
352 if (s->len_chanlist == 0)
356 ret = __comedi_device_postconfig_async(dev, s);
361 if (!s->range_table && !s->range_table_list)
362 s->range_table = &range_unknown;
364 if (!s->insn_read && s->insn_bits)
365 s->insn_read = insn_rw_emulate_bits;
366 if (!s->insn_write && s->insn_bits)
367 s->insn_write = insn_rw_emulate_bits;
370 s->insn_read = insn_inval;
372 s->insn_write = insn_inval;
374 s->insn_bits = insn_inval;
376 s->insn_config = insn_inval;
379 s->poll = poll_invalid;
385 /* do a little post-config cleanup */
386 static int comedi_device_postconfig(struct comedi_device *dev)
390 ret = __comedi_device_postconfig(dev);
393 down_write(&dev->attach_lock);
394 dev->attached = true;
395 up_write(&dev->attach_lock);
400 * Generic recognize function for drivers that register their supported
403 * 'driv->board_name' points to a 'const char *' member within the
404 * zeroth element of an array of some private board information
405 * structure, say 'struct foo_board' containing a member 'const char
406 * *board_name' that is initialized to point to a board name string that
407 * is one of the candidates matched against this function's 'name'
410 * 'driv->offset' is the size of the private board information
411 * structure, say 'sizeof(struct foo_board)', and 'driv->num_names' is
412 * the length of the array of private board information structures.
414 * If one of the board names in the array of private board information
415 * structures matches the name supplied to this function, the function
416 * returns a pointer to the pointer to the board name, otherwise it
417 * returns NULL. The return value ends up in the 'board_ptr' member of
418 * a 'struct comedi_device' that the low-level comedi driver's
419 * 'attach()' hook can convert to a point to a particular element of its
420 * array of private board information structures by subtracting the
421 * offset of the member that points to the board name. (No subtraction
422 * is required if the board name pointer is the first member of the
423 * private board information structure, which is generally the case.)
425 static void *comedi_recognize(struct comedi_driver *driv, const char *name)
427 char **name_ptr = (char **)driv->board_name;
430 for (i = 0; i < driv->num_names; i++) {
431 if (strcmp(*name_ptr, name) == 0)
433 name_ptr = (void *)name_ptr + driv->offset;
439 static void comedi_report_boards(struct comedi_driver *driv)
442 const char *const *name_ptr;
444 pr_info("comedi: valid board names for %s driver are:\n",
447 name_ptr = driv->board_name;
448 for (i = 0; i < driv->num_names; i++) {
449 pr_info(" %s\n", *name_ptr);
450 name_ptr = (const char **)((char *)name_ptr + driv->offset);
453 if (driv->num_names == 0)
454 pr_info(" %s\n", driv->driver_name);
458 * comedi_load_firmware() - Request and load firmware for a device.
459 * @dev: comedi_device struct
460 * @hw_device: device struct for the comedi_device
461 * @name: the name of the firmware image
462 * @cb: callback to the upload the firmware image
463 * @context: private context from the driver
465 int comedi_load_firmware(struct comedi_device *dev,
466 struct device *device,
468 int (*cb)(struct comedi_device *dev,
469 const u8 *data, size_t size,
470 unsigned long context),
471 unsigned long context)
473 const struct firmware *fw;
479 ret = request_firmware(&fw, name, device);
481 ret = cb(dev, fw->data, fw->size, context);
482 release_firmware(fw);
485 return ret < 0 ? ret : 0;
487 EXPORT_SYMBOL_GPL(comedi_load_firmware);
490 * __comedi_request_region() - Request an I/O reqion for a legacy driver.
491 * @dev: comedi_device struct
492 * @start: base address of the I/O reqion
493 * @len: length of the I/O region
495 int __comedi_request_region(struct comedi_device *dev,
496 unsigned long start, unsigned long len)
499 dev_warn(dev->class_dev,
500 "%s: a I/O base address must be specified\n",
505 if (!request_region(start, len, dev->board_name)) {
506 dev_warn(dev->class_dev, "%s: I/O port conflict (%#lx,%lu)\n",
507 dev->board_name, start, len);
513 EXPORT_SYMBOL_GPL(__comedi_request_region);
516 * comedi_request_region() - Request an I/O reqion for a legacy driver.
517 * @dev: comedi_device struct
518 * @start: base address of the I/O reqion
519 * @len: length of the I/O region
521 int comedi_request_region(struct comedi_device *dev,
522 unsigned long start, unsigned long len)
526 ret = __comedi_request_region(dev, start, len);
534 EXPORT_SYMBOL_GPL(comedi_request_region);
537 * comedi_legacy_detach() - A generic (*detach) function for legacy drivers.
538 * @dev: comedi_device struct
540 void comedi_legacy_detach(struct comedi_device *dev)
543 free_irq(dev->irq, dev);
546 if (dev->iobase && dev->iolen) {
547 release_region(dev->iobase, dev->iolen);
552 EXPORT_SYMBOL_GPL(comedi_legacy_detach);
554 int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it)
556 struct comedi_driver *driv;
562 mutex_lock(&comedi_drivers_list_lock);
563 for (driv = comedi_drivers; driv; driv = driv->next) {
564 if (!try_module_get(driv->module))
566 if (driv->num_names) {
567 dev->board_ptr = comedi_recognize(driv, it->board_name);
570 } else if (strcmp(driv->driver_name, it->board_name) == 0) {
573 module_put(driv->module);
576 /* recognize has failed if we get here */
577 /* report valid board names before returning error */
578 for (driv = comedi_drivers; driv; driv = driv->next) {
579 if (!try_module_get(driv->module))
581 comedi_report_boards(driv);
582 module_put(driv->module);
587 if (driv->attach == NULL) {
588 /* driver does not support manual configuration */
589 dev_warn(dev->class_dev,
590 "driver '%s' does not support attach using comedi_config\n",
592 module_put(driv->module);
597 dev->board_name = dev->board_ptr ? *(const char **)dev->board_ptr
598 : dev->driver->driver_name;
599 ret = driv->attach(dev, it);
601 ret = comedi_device_postconfig(dev);
603 comedi_device_detach(dev);
604 module_put(driv->module);
606 /* On success, the driver module count has been incremented. */
608 mutex_unlock(&comedi_drivers_list_lock);
612 int comedi_auto_config(struct device *hardware_device,
613 struct comedi_driver *driver, unsigned long context)
615 struct comedi_device *dev;
618 if (!hardware_device) {
619 pr_warn("BUG! comedi_auto_config called with NULL hardware_device\n");
623 dev_warn(hardware_device,
624 "BUG! comedi_auto_config called with NULL comedi driver\n");
628 if (!driver->auto_attach) {
629 dev_warn(hardware_device,
630 "BUG! comedi driver '%s' has no auto_attach handler\n",
631 driver->driver_name);
635 dev = comedi_alloc_board_minor(hardware_device);
637 dev_warn(hardware_device,
638 "driver '%s' could not create device.\n",
639 driver->driver_name);
642 /* Note: comedi_alloc_board_minor() locked dev->mutex. */
644 dev->driver = driver;
645 dev->board_name = dev->driver->driver_name;
646 ret = driver->auto_attach(dev, context);
648 ret = comedi_device_postconfig(dev);
649 mutex_unlock(&dev->mutex);
652 dev_warn(hardware_device,
653 "driver '%s' failed to auto-configure device.\n",
654 driver->driver_name);
655 comedi_release_hardware_device(hardware_device);
658 * class_dev should be set properly here
659 * after a successful auto config
661 dev_info(dev->class_dev,
662 "driver '%s' has successfully auto-configured '%s'.\n",
663 driver->driver_name, dev->board_name);
667 EXPORT_SYMBOL_GPL(comedi_auto_config);
669 void comedi_auto_unconfig(struct device *hardware_device)
671 if (hardware_device == NULL)
673 comedi_release_hardware_device(hardware_device);
675 EXPORT_SYMBOL_GPL(comedi_auto_unconfig);
677 int comedi_driver_register(struct comedi_driver *driver)
679 mutex_lock(&comedi_drivers_list_lock);
680 driver->next = comedi_drivers;
681 comedi_drivers = driver;
682 mutex_unlock(&comedi_drivers_list_lock);
686 EXPORT_SYMBOL_GPL(comedi_driver_register);
688 void comedi_driver_unregister(struct comedi_driver *driver)
690 struct comedi_driver *prev;
693 /* unlink the driver */
694 mutex_lock(&comedi_drivers_list_lock);
695 if (comedi_drivers == driver) {
696 comedi_drivers = driver->next;
698 for (prev = comedi_drivers; prev->next; prev = prev->next) {
699 if (prev->next == driver) {
700 prev->next = driver->next;
705 mutex_unlock(&comedi_drivers_list_lock);
707 /* check for devices using this driver */
708 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) {
709 struct comedi_device *dev = comedi_dev_get_from_minor(i);
714 mutex_lock(&dev->mutex);
715 if (dev->attached && dev->driver == driver) {
717 dev_warn(dev->class_dev,
718 "BUG! detaching device with use_count=%d\n",
720 comedi_device_detach(dev);
722 mutex_unlock(&dev->mutex);
726 EXPORT_SYMBOL_GPL(comedi_driver_unregister);