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.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #include <linux/device.h>
25 #include <linux/module.h>
26 #include <linux/errno.h>
27 #include <linux/kconfig.h>
28 #include <linux/kernel.h>
29 #include <linux/sched.h>
30 #include <linux/fcntl.h>
31 #include <linux/delay.h>
32 #include <linux/ioport.h>
34 #include <linux/slab.h>
35 #include <linux/highmem.h> /* for SuSE brokenness */
36 #include <linux/vmalloc.h>
37 #include <linux/cdev.h>
38 #include <linux/dma-mapping.h>
40 #include <linux/interrupt.h>
42 #include "comedidev.h"
43 #include "comedi_internal.h"
45 struct comedi_driver *comedi_drivers;
47 int comedi_set_hw_dev(struct comedi_device *dev, struct device *hw_dev)
49 if (hw_dev == dev->hw_dev)
51 if (dev->hw_dev != NULL)
53 dev->hw_dev = get_device(hw_dev);
56 EXPORT_SYMBOL_GPL(comedi_set_hw_dev);
58 static void comedi_clear_hw_dev(struct comedi_device *dev)
60 put_device(dev->hw_dev);
64 int comedi_alloc_subdevices(struct comedi_device *dev, int num_subdevices)
66 struct comedi_subdevice *s;
69 if (num_subdevices < 1)
72 s = kcalloc(num_subdevices, sizeof(*s), GFP_KERNEL);
76 dev->n_subdevices = num_subdevices;
78 for (i = 0; i < num_subdevices; ++i) {
79 s = &dev->subdevices[i];
82 s->async_dma_dir = DMA_NONE;
83 spin_lock_init(&s->spin_lock);
88 EXPORT_SYMBOL_GPL(comedi_alloc_subdevices);
90 void comedi_spriv_free(struct comedi_device *dev, int subdev_num)
92 struct comedi_subdevice *s;
94 if (dev->subdevices && subdev_num < dev->n_subdevices) {
95 s = &dev->subdevices[subdev_num];
100 EXPORT_SYMBOL_GPL(comedi_spriv_free);
102 static void cleanup_device(struct comedi_device *dev)
105 struct comedi_subdevice *s;
107 if (dev->subdevices) {
108 for (i = 0; i < dev->n_subdevices; i++) {
109 s = &dev->subdevices[i];
110 comedi_free_subdevice_minor(s);
112 comedi_buf_alloc(dev, s, 0);
116 kfree(dev->subdevices);
117 dev->subdevices = NULL;
118 dev->n_subdevices = 0;
123 dev->board_name = NULL;
124 dev->board_ptr = NULL;
127 dev->ioenabled = false;
129 dev->read_subdev = NULL;
130 dev->write_subdev = NULL;
133 comedi_clear_hw_dev(dev);
136 void comedi_device_detach(struct comedi_device *dev)
138 dev->attached = false;
140 dev->driver->detach(dev);
144 static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s)
149 int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s,
150 struct comedi_insn *insn, unsigned int *data)
155 static int insn_rw_emulate_bits(struct comedi_device *dev,
156 struct comedi_subdevice *s,
157 struct comedi_insn *insn, unsigned int *data)
159 struct comedi_insn new_insn;
161 static const unsigned channels_per_bitfield = 32;
163 unsigned chan = CR_CHAN(insn->chanspec);
164 const unsigned base_bitfield_channel =
165 (chan < channels_per_bitfield) ? 0 : chan;
166 unsigned int new_data[2];
167 memset(new_data, 0, sizeof(new_data));
168 memset(&new_insn, 0, sizeof(new_insn));
169 new_insn.insn = INSN_BITS;
170 new_insn.chanspec = base_bitfield_channel;
172 new_insn.subdev = insn->subdev;
174 if (insn->insn == INSN_WRITE) {
175 if (!(s->subdev_flags & SDF_WRITABLE))
177 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */
178 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel))
182 ret = s->insn_bits(dev, s, &new_insn, new_data);
186 if (insn->insn == INSN_READ)
187 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1;
192 static int __comedi_device_postconfig_async(struct comedi_device *dev,
193 struct comedi_subdevice *s)
195 struct comedi_async *async;
196 unsigned int buf_size;
199 if ((s->subdev_flags & (SDF_CMD_READ | SDF_CMD_WRITE)) == 0) {
200 dev_warn(dev->class_dev,
201 "async subdevices must support SDF_CMD_READ or SDF_CMD_WRITE\n");
204 if (!s->do_cmdtest) {
205 dev_warn(dev->class_dev,
206 "async subdevices must have a do_cmdtest() function\n");
210 async = kzalloc(sizeof(*async), GFP_KERNEL);
214 init_waitqueue_head(&async->wait_head);
215 async->subdevice = s;
218 async->max_bufsize = comedi_default_buf_maxsize_kb * 1024;
219 buf_size = comedi_default_buf_size_kb * 1024;
220 if (buf_size > async->max_bufsize)
221 buf_size = async->max_bufsize;
223 if (comedi_buf_alloc(dev, s, buf_size) < 0) {
224 dev_warn(dev->class_dev, "Buffer allocation failed\n");
228 ret = s->buf_change(dev, s, buf_size);
233 comedi_alloc_subdevice_minor(s);
238 static int __comedi_device_postconfig(struct comedi_device *dev)
240 struct comedi_subdevice *s;
244 for (i = 0; i < dev->n_subdevices; i++) {
245 s = &dev->subdevices[i];
247 if (s->type == COMEDI_SUBD_UNUSED)
250 if (s->len_chanlist == 0)
254 ret = __comedi_device_postconfig_async(dev, s);
259 if (!s->range_table && !s->range_table_list)
260 s->range_table = &range_unknown;
262 if (!s->insn_read && s->insn_bits)
263 s->insn_read = insn_rw_emulate_bits;
264 if (!s->insn_write && s->insn_bits)
265 s->insn_write = insn_rw_emulate_bits;
268 s->insn_read = insn_inval;
270 s->insn_write = insn_inval;
272 s->insn_bits = insn_inval;
274 s->insn_config = insn_inval;
277 s->poll = poll_invalid;
283 /* do a little post-config cleanup */
284 static int comedi_device_postconfig(struct comedi_device *dev)
288 ret = __comedi_device_postconfig(dev);
292 dev->attached = true;
297 * Generic recognize function for drivers that register their supported
300 * 'driv->board_name' points to a 'const char *' member within the
301 * zeroth element of an array of some private board information
302 * structure, say 'struct foo_board' containing a member 'const char
303 * *board_name' that is initialized to point to a board name string that
304 * is one of the candidates matched against this function's 'name'
307 * 'driv->offset' is the size of the private board information
308 * structure, say 'sizeof(struct foo_board)', and 'driv->num_names' is
309 * the length of the array of private board information structures.
311 * If one of the board names in the array of private board information
312 * structures matches the name supplied to this function, the function
313 * returns a pointer to the pointer to the board name, otherwise it
314 * returns NULL. The return value ends up in the 'board_ptr' member of
315 * a 'struct comedi_device' that the low-level comedi driver's
316 * 'attach()' hook can convert to a point to a particular element of its
317 * array of private board information structures by subtracting the
318 * offset of the member that points to the board name. (No subtraction
319 * is required if the board name pointer is the first member of the
320 * private board information structure, which is generally the case.)
322 static void *comedi_recognize(struct comedi_driver *driv, const char *name)
324 char **name_ptr = (char **)driv->board_name;
327 for (i = 0; i < driv->num_names; i++) {
328 if (strcmp(*name_ptr, name) == 0)
330 name_ptr = (void *)name_ptr + driv->offset;
336 static void comedi_report_boards(struct comedi_driver *driv)
339 const char *const *name_ptr;
341 pr_info("comedi: valid board names for %s driver are:\n",
344 name_ptr = driv->board_name;
345 for (i = 0; i < driv->num_names; i++) {
346 pr_info(" %s\n", *name_ptr);
347 name_ptr = (const char **)((char *)name_ptr + driv->offset);
350 if (driv->num_names == 0)
351 pr_info(" %s\n", driv->driver_name);
355 * __comedi_request_region() - Request an I/O reqion for a legacy driver.
356 * @dev: comedi_device struct
357 * @start: base address of the I/O reqion
358 * @len: length of the I/O region
360 int __comedi_request_region(struct comedi_device *dev,
361 unsigned long start, unsigned long len)
364 dev_warn(dev->class_dev,
365 "%s: a I/O base address must be specified\n",
370 if (!request_region(start, len, dev->board_name)) {
371 dev_warn(dev->class_dev, "%s: I/O port conflict (%#lx,%lu)\n",
372 dev->board_name, start, len);
378 EXPORT_SYMBOL_GPL(__comedi_request_region);
381 * comedi_request_region() - Request an I/O reqion for a legacy driver.
382 * @dev: comedi_device struct
383 * @start: base address of the I/O reqion
384 * @len: length of the I/O region
386 int comedi_request_region(struct comedi_device *dev,
387 unsigned long start, unsigned long len)
391 ret = __comedi_request_region(dev, start, len);
399 EXPORT_SYMBOL_GPL(comedi_request_region);
402 * comedi_legacy_detach() - A generic (*detach) function for legacy drivers.
403 * @dev: comedi_device struct
405 void comedi_legacy_detach(struct comedi_device *dev)
408 free_irq(dev->irq, dev);
411 if (dev->iobase && dev->iolen) {
412 release_region(dev->iobase, dev->iolen);
417 EXPORT_SYMBOL_GPL(comedi_legacy_detach);
419 int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it)
421 struct comedi_driver *driv;
427 for (driv = comedi_drivers; driv; driv = driv->next) {
428 if (!try_module_get(driv->module))
430 if (driv->num_names) {
431 dev->board_ptr = comedi_recognize(driv, it->board_name);
434 } else if (strcmp(driv->driver_name, it->board_name) == 0)
436 module_put(driv->module);
439 /* recognize has failed if we get here */
440 /* report valid board names before returning error */
441 for (driv = comedi_drivers; driv; driv = driv->next) {
442 if (!try_module_get(driv->module))
444 comedi_report_boards(driv);
445 module_put(driv->module);
449 if (driv->attach == NULL) {
450 /* driver does not support manual configuration */
451 dev_warn(dev->class_dev,
452 "driver '%s' does not support attach using comedi_config\n",
454 module_put(driv->module);
457 /* initialize dev->driver here so
458 * comedi_error() can be called from attach */
460 dev->board_name = dev->board_ptr ? *(const char **)dev->board_ptr
461 : dev->driver->driver_name;
462 ret = driv->attach(dev, it);
464 ret = comedi_device_postconfig(dev);
466 comedi_device_detach(dev);
467 module_put(driv->module);
469 /* On success, the driver module count has been incremented. */
473 int comedi_auto_config(struct device *hardware_device,
474 struct comedi_driver *driver, unsigned long context)
476 struct comedi_device *dev;
479 if (!hardware_device) {
480 pr_warn("BUG! comedi_auto_config called with NULL hardware_device\n");
484 dev_warn(hardware_device,
485 "BUG! comedi_auto_config called with NULL comedi driver\n");
489 if (!driver->auto_attach) {
490 dev_warn(hardware_device,
491 "BUG! comedi driver '%s' has no auto_attach handler\n",
492 driver->driver_name);
496 dev = comedi_alloc_board_minor(hardware_device);
499 /* Note: comedi_alloc_board_minor() locked dev->mutex. */
501 dev->driver = driver;
502 dev->board_name = dev->driver->driver_name;
503 ret = driver->auto_attach(dev, context);
505 ret = comedi_device_postconfig(dev);
507 comedi_device_detach(dev);
508 mutex_unlock(&dev->mutex);
511 comedi_release_hardware_device(hardware_device);
514 EXPORT_SYMBOL_GPL(comedi_auto_config);
516 void comedi_auto_unconfig(struct device *hardware_device)
518 if (hardware_device == NULL)
520 comedi_release_hardware_device(hardware_device);
522 EXPORT_SYMBOL_GPL(comedi_auto_unconfig);
524 int comedi_driver_register(struct comedi_driver *driver)
526 driver->next = comedi_drivers;
527 comedi_drivers = driver;
531 EXPORT_SYMBOL_GPL(comedi_driver_register);
533 int comedi_driver_unregister(struct comedi_driver *driver)
535 struct comedi_driver *prev;
538 /* check for devices using this driver */
539 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) {
540 struct comedi_device *dev = comedi_dev_from_minor(i);
545 mutex_lock(&dev->mutex);
546 if (dev->attached && dev->driver == driver) {
548 dev_warn(dev->class_dev,
549 "BUG! detaching device with use_count=%d\n",
551 comedi_device_detach(dev);
553 mutex_unlock(&dev->mutex);
556 if (comedi_drivers == driver) {
557 comedi_drivers = driver->next;
561 for (prev = comedi_drivers; prev->next; prev = prev->next) {
562 if (prev->next == driver) {
563 prev->next = driver->next;
569 EXPORT_SYMBOL_GPL(comedi_driver_unregister);