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 DEFINE_MUTEX(comedi_drivers_list_lock);
43 int comedi_set_hw_dev(struct comedi_device *dev, struct device *hw_dev)
45 if (hw_dev == dev->hw_dev)
47 if (dev->hw_dev != NULL)
49 dev->hw_dev = get_device(hw_dev);
52 EXPORT_SYMBOL_GPL(comedi_set_hw_dev);
54 static void comedi_clear_hw_dev(struct comedi_device *dev)
56 put_device(dev->hw_dev);
61 * comedi_alloc_devpriv() - Allocate memory for the device private data.
62 * @dev: comedi_device struct
63 * @size: size of the memory to allocate
65 void *comedi_alloc_devpriv(struct comedi_device *dev, size_t size)
67 dev->private = kzalloc(size, GFP_KERNEL);
70 EXPORT_SYMBOL_GPL(comedi_alloc_devpriv);
72 int comedi_alloc_subdevices(struct comedi_device *dev, int num_subdevices)
74 struct comedi_subdevice *s;
77 if (num_subdevices < 1)
80 s = kcalloc(num_subdevices, sizeof(*s), GFP_KERNEL);
84 dev->n_subdevices = num_subdevices;
86 for (i = 0; i < num_subdevices; ++i) {
87 s = &dev->subdevices[i];
90 s->async_dma_dir = DMA_NONE;
91 spin_lock_init(&s->spin_lock);
96 EXPORT_SYMBOL_GPL(comedi_alloc_subdevices);
98 static void cleanup_device(struct comedi_device *dev)
101 struct comedi_subdevice *s;
103 if (dev->subdevices) {
104 for (i = 0; i < dev->n_subdevices; i++) {
105 s = &dev->subdevices[i];
106 if (s->runflags & SRF_FREE_SPRIV)
108 comedi_free_subdevice_minor(s);
110 comedi_buf_alloc(dev, s, 0);
114 kfree(dev->subdevices);
115 dev->subdevices = NULL;
116 dev->n_subdevices = 0;
121 dev->board_name = NULL;
122 dev->board_ptr = NULL;
125 dev->ioenabled = false;
127 dev->read_subdev = NULL;
128 dev->write_subdev = NULL;
131 comedi_clear_hw_dev(dev);
134 void comedi_device_detach(struct comedi_device *dev)
136 dev->attached = false;
138 dev->driver->detach(dev);
142 static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s)
147 int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s,
148 struct comedi_insn *insn, unsigned int *data)
154 * comedi_dio_insn_config() - boilerplate (*insn_config) for DIO subdevices.
155 * @dev: comedi_device struct
156 * @s: comedi_subdevice struct
157 * @insn: comedi_insn struct
158 * @data: parameters for the @insn
159 * @mask: io_bits mask for grouped channels
161 int comedi_dio_insn_config(struct comedi_device *dev,
162 struct comedi_subdevice *s,
163 struct comedi_insn *insn,
167 unsigned int chan_mask = 1 << CR_CHAN(insn->chanspec);
173 case INSN_CONFIG_DIO_INPUT:
177 case INSN_CONFIG_DIO_OUTPUT:
181 case INSN_CONFIG_DIO_QUERY:
182 data[1] = (s->io_bits & mask) ? COMEDI_OUTPUT : COMEDI_INPUT;
191 EXPORT_SYMBOL_GPL(comedi_dio_insn_config);
194 * comedi_dio_update_state() - update the internal state of DIO subdevices.
195 * @s: comedi_subdevice struct
196 * @data: the channel mask and bits to update
198 unsigned int comedi_dio_update_state(struct comedi_subdevice *s,
201 unsigned int chanmask = (s->n_chan < 32) ? ((1 << s->n_chan) - 1)
203 unsigned int mask = data[0] & chanmask;
204 unsigned int bits = data[1];
208 s->state |= (bits & mask);
213 EXPORT_SYMBOL_GPL(comedi_dio_update_state);
215 static int insn_rw_emulate_bits(struct comedi_device *dev,
216 struct comedi_subdevice *s,
217 struct comedi_insn *insn, unsigned int *data)
219 struct comedi_insn new_insn;
221 static const unsigned channels_per_bitfield = 32;
223 unsigned chan = CR_CHAN(insn->chanspec);
224 const unsigned base_bitfield_channel =
225 (chan < channels_per_bitfield) ? 0 : chan;
226 unsigned int new_data[2];
227 memset(new_data, 0, sizeof(new_data));
228 memset(&new_insn, 0, sizeof(new_insn));
229 new_insn.insn = INSN_BITS;
230 new_insn.chanspec = base_bitfield_channel;
232 new_insn.subdev = insn->subdev;
234 if (insn->insn == INSN_WRITE) {
235 if (!(s->subdev_flags & SDF_WRITABLE))
237 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */
238 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel))
242 ret = s->insn_bits(dev, s, &new_insn, new_data);
246 if (insn->insn == INSN_READ)
247 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1;
252 static int __comedi_device_postconfig_async(struct comedi_device *dev,
253 struct comedi_subdevice *s)
255 struct comedi_async *async;
256 unsigned int buf_size;
259 if ((s->subdev_flags & (SDF_CMD_READ | SDF_CMD_WRITE)) == 0) {
260 dev_warn(dev->class_dev,
261 "async subdevices must support SDF_CMD_READ or SDF_CMD_WRITE\n");
264 if (!s->do_cmdtest) {
265 dev_warn(dev->class_dev,
266 "async subdevices must have a do_cmdtest() function\n");
270 async = kzalloc(sizeof(*async), GFP_KERNEL);
274 init_waitqueue_head(&async->wait_head);
275 async->subdevice = s;
278 async->max_bufsize = comedi_default_buf_maxsize_kb * 1024;
279 buf_size = comedi_default_buf_size_kb * 1024;
280 if (buf_size > async->max_bufsize)
281 buf_size = async->max_bufsize;
283 if (comedi_buf_alloc(dev, s, buf_size) < 0) {
284 dev_warn(dev->class_dev, "Buffer allocation failed\n");
288 ret = s->buf_change(dev, s, buf_size);
293 comedi_alloc_subdevice_minor(s);
298 static int __comedi_device_postconfig(struct comedi_device *dev)
300 struct comedi_subdevice *s;
304 for (i = 0; i < dev->n_subdevices; i++) {
305 s = &dev->subdevices[i];
307 if (s->type == COMEDI_SUBD_UNUSED)
310 if (s->type == COMEDI_SUBD_DO) {
312 s->io_bits = (1 << s->n_chan) - 1;
314 s->io_bits = 0xffffffff;
317 if (s->len_chanlist == 0)
321 ret = __comedi_device_postconfig_async(dev, s);
326 if (!s->range_table && !s->range_table_list)
327 s->range_table = &range_unknown;
329 if (!s->insn_read && s->insn_bits)
330 s->insn_read = insn_rw_emulate_bits;
331 if (!s->insn_write && s->insn_bits)
332 s->insn_write = insn_rw_emulate_bits;
335 s->insn_read = insn_inval;
337 s->insn_write = insn_inval;
339 s->insn_bits = insn_inval;
341 s->insn_config = insn_inval;
344 s->poll = poll_invalid;
350 /* do a little post-config cleanup */
351 static int comedi_device_postconfig(struct comedi_device *dev)
355 ret = __comedi_device_postconfig(dev);
359 dev->attached = true;
364 * Generic recognize function for drivers that register their supported
367 * 'driv->board_name' points to a 'const char *' member within the
368 * zeroth element of an array of some private board information
369 * structure, say 'struct foo_board' containing a member 'const char
370 * *board_name' that is initialized to point to a board name string that
371 * is one of the candidates matched against this function's 'name'
374 * 'driv->offset' is the size of the private board information
375 * structure, say 'sizeof(struct foo_board)', and 'driv->num_names' is
376 * the length of the array of private board information structures.
378 * If one of the board names in the array of private board information
379 * structures matches the name supplied to this function, the function
380 * returns a pointer to the pointer to the board name, otherwise it
381 * returns NULL. The return value ends up in the 'board_ptr' member of
382 * a 'struct comedi_device' that the low-level comedi driver's
383 * 'attach()' hook can convert to a point to a particular element of its
384 * array of private board information structures by subtracting the
385 * offset of the member that points to the board name. (No subtraction
386 * is required if the board name pointer is the first member of the
387 * private board information structure, which is generally the case.)
389 static void *comedi_recognize(struct comedi_driver *driv, const char *name)
391 char **name_ptr = (char **)driv->board_name;
394 for (i = 0; i < driv->num_names; i++) {
395 if (strcmp(*name_ptr, name) == 0)
397 name_ptr = (void *)name_ptr + driv->offset;
403 static void comedi_report_boards(struct comedi_driver *driv)
406 const char *const *name_ptr;
408 pr_info("comedi: valid board names for %s driver are:\n",
411 name_ptr = driv->board_name;
412 for (i = 0; i < driv->num_names; i++) {
413 pr_info(" %s\n", *name_ptr);
414 name_ptr = (const char **)((char *)name_ptr + driv->offset);
417 if (driv->num_names == 0)
418 pr_info(" %s\n", driv->driver_name);
422 * comedi_load_firmware() - Request and load firmware for a device.
423 * @dev: comedi_device struct
424 * @hw_device: device struct for the comedi_device
425 * @name: the name of the firmware image
426 * @cb: callback to the upload the firmware image
427 * @context: private context from the driver
429 int comedi_load_firmware(struct comedi_device *dev,
430 struct device *device,
432 int (*cb)(struct comedi_device *dev,
433 const u8 *data, size_t size,
434 unsigned long context),
435 unsigned long context)
437 const struct firmware *fw;
443 ret = request_firmware(&fw, name, device);
445 ret = cb(dev, fw->data, fw->size, context);
446 release_firmware(fw);
451 EXPORT_SYMBOL_GPL(comedi_load_firmware);
454 * __comedi_request_region() - Request an I/O reqion for a legacy driver.
455 * @dev: comedi_device struct
456 * @start: base address of the I/O reqion
457 * @len: length of the I/O region
459 int __comedi_request_region(struct comedi_device *dev,
460 unsigned long start, unsigned long len)
463 dev_warn(dev->class_dev,
464 "%s: a I/O base address must be specified\n",
469 if (!request_region(start, len, dev->board_name)) {
470 dev_warn(dev->class_dev, "%s: I/O port conflict (%#lx,%lu)\n",
471 dev->board_name, start, len);
477 EXPORT_SYMBOL_GPL(__comedi_request_region);
480 * comedi_request_region() - Request an I/O reqion for a legacy driver.
481 * @dev: comedi_device struct
482 * @start: base address of the I/O reqion
483 * @len: length of the I/O region
485 int comedi_request_region(struct comedi_device *dev,
486 unsigned long start, unsigned long len)
490 ret = __comedi_request_region(dev, start, len);
498 EXPORT_SYMBOL_GPL(comedi_request_region);
501 * comedi_legacy_detach() - A generic (*detach) function for legacy drivers.
502 * @dev: comedi_device struct
504 void comedi_legacy_detach(struct comedi_device *dev)
507 free_irq(dev->irq, dev);
510 if (dev->iobase && dev->iolen) {
511 release_region(dev->iobase, dev->iolen);
516 EXPORT_SYMBOL_GPL(comedi_legacy_detach);
518 int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it)
520 struct comedi_driver *driv;
526 mutex_lock(&comedi_drivers_list_lock);
527 for (driv = comedi_drivers; driv; driv = driv->next) {
528 if (!try_module_get(driv->module))
530 if (driv->num_names) {
531 dev->board_ptr = comedi_recognize(driv, it->board_name);
534 } else if (strcmp(driv->driver_name, it->board_name) == 0)
536 module_put(driv->module);
539 /* recognize has failed if we get here */
540 /* report valid board names before returning error */
541 for (driv = comedi_drivers; driv; driv = driv->next) {
542 if (!try_module_get(driv->module))
544 comedi_report_boards(driv);
545 module_put(driv->module);
550 if (driv->attach == NULL) {
551 /* driver does not support manual configuration */
552 dev_warn(dev->class_dev,
553 "driver '%s' does not support attach using comedi_config\n",
555 module_put(driv->module);
559 /* initialize dev->driver here so
560 * comedi_error() can be called from attach */
562 dev->board_name = dev->board_ptr ? *(const char **)dev->board_ptr
563 : dev->driver->driver_name;
564 ret = driv->attach(dev, it);
566 ret = comedi_device_postconfig(dev);
568 comedi_device_detach(dev);
569 module_put(driv->module);
571 /* On success, the driver module count has been incremented. */
573 mutex_unlock(&comedi_drivers_list_lock);
577 int comedi_auto_config(struct device *hardware_device,
578 struct comedi_driver *driver, unsigned long context)
580 struct comedi_device *dev;
583 if (!hardware_device) {
584 pr_warn("BUG! comedi_auto_config called with NULL hardware_device\n");
588 dev_warn(hardware_device,
589 "BUG! comedi_auto_config called with NULL comedi driver\n");
593 if (!driver->auto_attach) {
594 dev_warn(hardware_device,
595 "BUG! comedi driver '%s' has no auto_attach handler\n",
596 driver->driver_name);
600 dev = comedi_alloc_board_minor(hardware_device);
603 /* Note: comedi_alloc_board_minor() locked dev->mutex. */
605 dev->driver = driver;
606 dev->board_name = dev->driver->driver_name;
607 ret = driver->auto_attach(dev, context);
609 ret = comedi_device_postconfig(dev);
611 comedi_device_detach(dev);
612 mutex_unlock(&dev->mutex);
615 comedi_release_hardware_device(hardware_device);
618 EXPORT_SYMBOL_GPL(comedi_auto_config);
620 void comedi_auto_unconfig(struct device *hardware_device)
622 if (hardware_device == NULL)
624 comedi_release_hardware_device(hardware_device);
626 EXPORT_SYMBOL_GPL(comedi_auto_unconfig);
628 int comedi_driver_register(struct comedi_driver *driver)
630 mutex_lock(&comedi_drivers_list_lock);
631 driver->next = comedi_drivers;
632 comedi_drivers = driver;
633 mutex_unlock(&comedi_drivers_list_lock);
637 EXPORT_SYMBOL_GPL(comedi_driver_register);
639 void comedi_driver_unregister(struct comedi_driver *driver)
641 struct comedi_driver *prev;
644 /* unlink the driver */
645 mutex_lock(&comedi_drivers_list_lock);
646 if (comedi_drivers == driver) {
647 comedi_drivers = driver->next;
649 for (prev = comedi_drivers; prev->next; prev = prev->next) {
650 if (prev->next == driver) {
651 prev->next = driver->next;
656 mutex_unlock(&comedi_drivers_list_lock);
658 /* check for devices using this driver */
659 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) {
660 struct comedi_device *dev = comedi_dev_from_minor(i);
665 mutex_lock(&dev->mutex);
666 if (dev->attached && dev->driver == driver) {
668 dev_warn(dev->class_dev,
669 "BUG! detaching device with use_count=%d\n",
671 comedi_device_detach(dev);
673 mutex_unlock(&dev->mutex);
676 EXPORT_SYMBOL_GPL(comedi_driver_unregister);