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 <pcmcia/cistpl.h>
27 #include <pcmcia/ds.h>
28 #include <linux/errno.h>
29 #include <linux/kconfig.h>
30 #include <linux/kernel.h>
31 #include <linux/sched.h>
32 #include <linux/fcntl.h>
33 #include <linux/delay.h>
34 #include <linux/ioport.h>
36 #include <linux/slab.h>
37 #include <linux/highmem.h> /* for SuSE brokenness */
38 #include <linux/vmalloc.h>
39 #include <linux/cdev.h>
40 #include <linux/dma-mapping.h>
43 #include "comedidev.h"
44 #include "comedi_internal.h"
46 struct comedi_driver *comedi_drivers;
48 int comedi_alloc_subdevices(struct comedi_device *dev, int num_subdevices)
50 struct comedi_subdevice *s;
53 if (num_subdevices < 1)
56 s = kcalloc(num_subdevices, sizeof(*s), GFP_KERNEL);
60 dev->n_subdevices = num_subdevices;
62 for (i = 0; i < num_subdevices; ++i) {
63 s = &dev->subdevices[i];
66 s->async_dma_dir = DMA_NONE;
67 spin_lock_init(&s->spin_lock);
72 EXPORT_SYMBOL_GPL(comedi_alloc_subdevices);
74 static void cleanup_device(struct comedi_device *dev)
77 struct comedi_subdevice *s;
79 if (dev->subdevices) {
80 for (i = 0; i < dev->n_subdevices; i++) {
81 s = &dev->subdevices[i];
82 comedi_free_subdevice_minor(s);
84 comedi_buf_alloc(dev, s, 0);
88 kfree(dev->subdevices);
89 dev->subdevices = NULL;
90 dev->n_subdevices = 0;
95 dev->board_name = NULL;
96 dev->board_ptr = NULL;
99 dev->read_subdev = NULL;
100 dev->write_subdev = NULL;
103 comedi_set_hw_dev(dev, NULL);
106 static void __comedi_device_detach(struct comedi_device *dev)
110 dev->driver->detach(dev);
112 dev_warn(dev->class_dev,
113 "BUG: dev->driver=NULL in comedi_device_detach()\n");
117 void comedi_device_detach(struct comedi_device *dev)
121 __comedi_device_detach(dev);
124 static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s)
129 int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s,
130 struct comedi_insn *insn, unsigned int *data)
135 static int insn_rw_emulate_bits(struct comedi_device *dev,
136 struct comedi_subdevice *s,
137 struct comedi_insn *insn, unsigned int *data)
139 struct comedi_insn new_insn;
141 static const unsigned channels_per_bitfield = 32;
143 unsigned chan = CR_CHAN(insn->chanspec);
144 const unsigned base_bitfield_channel =
145 (chan < channels_per_bitfield) ? 0 : chan;
146 unsigned int new_data[2];
147 memset(new_data, 0, sizeof(new_data));
148 memset(&new_insn, 0, sizeof(new_insn));
149 new_insn.insn = INSN_BITS;
150 new_insn.chanspec = base_bitfield_channel;
152 new_insn.subdev = insn->subdev;
154 if (insn->insn == INSN_WRITE) {
155 if (!(s->subdev_flags & SDF_WRITABLE))
157 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */
158 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel))
162 ret = s->insn_bits(dev, s, &new_insn, new_data);
166 if (insn->insn == INSN_READ)
167 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1;
172 static int __comedi_device_postconfig_async(struct comedi_device *dev,
173 struct comedi_subdevice *s)
175 struct comedi_async *async;
176 unsigned int buf_size;
179 if ((s->subdev_flags & (SDF_CMD_READ | SDF_CMD_WRITE)) == 0) {
180 dev_warn(dev->class_dev,
181 "async subdevices must support SDF_CMD_READ or SDF_CMD_WRITE\n");
184 if (!s->do_cmdtest) {
185 dev_warn(dev->class_dev,
186 "async subdevices must have a do_cmdtest() function\n");
190 async = kzalloc(sizeof(*async), GFP_KERNEL);
192 dev_warn(dev->class_dev, "failed to allocate async struct\n");
195 init_waitqueue_head(&async->wait_head);
196 async->subdevice = s;
199 async->max_bufsize = comedi_default_buf_maxsize_kb * 1024;
200 buf_size = comedi_default_buf_size_kb * 1024;
201 if (buf_size > async->max_bufsize)
202 buf_size = async->max_bufsize;
204 if (comedi_buf_alloc(dev, s, buf_size) < 0) {
205 dev_warn(dev->class_dev, "Buffer allocation failed\n");
209 ret = s->buf_change(dev, s, buf_size);
214 comedi_alloc_subdevice_minor(dev, s);
219 static int __comedi_device_postconfig(struct comedi_device *dev)
221 struct comedi_subdevice *s;
225 for (i = 0; i < dev->n_subdevices; i++) {
226 s = &dev->subdevices[i];
228 if (s->type == COMEDI_SUBD_UNUSED)
231 if (s->len_chanlist == 0)
235 ret = __comedi_device_postconfig_async(dev, s);
240 if (!s->range_table && !s->range_table_list)
241 s->range_table = &range_unknown;
243 if (!s->insn_read && s->insn_bits)
244 s->insn_read = insn_rw_emulate_bits;
245 if (!s->insn_write && s->insn_bits)
246 s->insn_write = insn_rw_emulate_bits;
249 s->insn_read = insn_inval;
251 s->insn_write = insn_inval;
253 s->insn_bits = insn_inval;
255 s->insn_config = insn_inval;
258 s->poll = poll_invalid;
264 /* do a little post-config cleanup */
265 /* called with module refcount incremented, decrements it */
266 static int comedi_device_postconfig(struct comedi_device *dev)
268 int ret = __comedi_device_postconfig(dev);
269 module_put(dev->driver->module);
271 __comedi_device_detach(dev);
274 if (!dev->board_name) {
275 dev_warn(dev->class_dev, "BUG: dev->board_name=NULL\n");
276 dev->board_name = "BUG";
284 * Generic recognize function for drivers that register their supported
287 * 'driv->board_name' points to a 'const char *' member within the
288 * zeroth element of an array of some private board information
289 * structure, say 'struct foo_board' containing a member 'const char
290 * *board_name' that is initialized to point to a board name string that
291 * is one of the candidates matched against this function's 'name'
294 * 'driv->offset' is the size of the private board information
295 * structure, say 'sizeof(struct foo_board)', and 'driv->num_names' is
296 * the length of the array of private board information structures.
298 * If one of the board names in the array of private board information
299 * structures matches the name supplied to this function, the function
300 * returns a pointer to the pointer to the board name, otherwise it
301 * returns NULL. The return value ends up in the 'board_ptr' member of
302 * a 'struct comedi_device' that the low-level comedi driver's
303 * 'attach()' hook can convert to a point to a particular element of its
304 * array of private board information structures by subtracting the
305 * offset of the member that points to the board name. (No subtraction
306 * is required if the board name pointer is the first member of the
307 * private board information structure, which is generally the case.)
309 static void *comedi_recognize(struct comedi_driver *driv, const char *name)
311 char **name_ptr = (char **)driv->board_name;
314 for (i = 0; i < driv->num_names; i++) {
315 if (strcmp(*name_ptr, name) == 0)
317 name_ptr = (void *)name_ptr + driv->offset;
323 static void comedi_report_boards(struct comedi_driver *driv)
326 const char *const *name_ptr;
328 pr_info("comedi: valid board names for %s driver are:\n",
331 name_ptr = driv->board_name;
332 for (i = 0; i < driv->num_names; i++) {
333 pr_info(" %s\n", *name_ptr);
334 name_ptr = (const char **)((char *)name_ptr + driv->offset);
337 if (driv->num_names == 0)
338 pr_info(" %s\n", driv->driver_name);
341 int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it)
343 struct comedi_driver *driv;
349 for (driv = comedi_drivers; driv; driv = driv->next) {
350 if (!try_module_get(driv->module))
352 if (driv->num_names) {
353 dev->board_ptr = comedi_recognize(driv, it->board_name);
356 } else if (strcmp(driv->driver_name, it->board_name) == 0)
358 module_put(driv->module);
361 /* recognize has failed if we get here */
362 /* report valid board names before returning error */
363 for (driv = comedi_drivers; driv; driv = driv->next) {
364 if (!try_module_get(driv->module))
366 comedi_report_boards(driv);
367 module_put(driv->module);
371 if (driv->attach == NULL) {
372 /* driver does not support manual configuration */
373 dev_warn(dev->class_dev,
374 "driver '%s' does not support attach using comedi_config\n",
376 module_put(driv->module);
379 /* initialize dev->driver here so
380 * comedi_error() can be called from attach */
382 ret = driv->attach(dev, it);
384 module_put(dev->driver->module);
385 __comedi_device_detach(dev);
388 return comedi_device_postconfig(dev);
391 int comedi_driver_register(struct comedi_driver *driver)
393 driver->next = comedi_drivers;
394 comedi_drivers = driver;
398 EXPORT_SYMBOL(comedi_driver_register);
400 int comedi_driver_unregister(struct comedi_driver *driver)
402 struct comedi_driver *prev;
405 /* check for devices using this driver */
406 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) {
407 struct comedi_device *dev = comedi_dev_from_minor(i);
412 mutex_lock(&dev->mutex);
413 if (dev->attached && dev->driver == driver) {
415 dev_warn(dev->class_dev,
416 "BUG! detaching device with use_count=%d\n",
418 comedi_device_detach(dev);
420 mutex_unlock(&dev->mutex);
423 if (comedi_drivers == driver) {
424 comedi_drivers = driver->next;
428 for (prev = comedi_drivers; prev->next; prev = prev->next) {
429 if (prev->next == driver) {
430 prev->next = driver->next;
436 EXPORT_SYMBOL(comedi_driver_unregister);
438 int comedi_auto_config(struct device *hardware_device,
439 struct comedi_driver *driver, unsigned long context)
442 struct comedi_device *comedi_dev;
445 if (!comedi_autoconfig)
448 if (!driver->auto_attach) {
449 dev_warn(hardware_device,
450 "BUG! comedi driver '%s' has no auto_attach handler\n",
451 driver->driver_name);
455 minor = comedi_alloc_board_minor(hardware_device);
459 comedi_dev = comedi_dev_from_minor(minor);
461 mutex_lock(&comedi_dev->mutex);
462 if (comedi_dev->attached)
464 else if (!try_module_get(driver->module))
467 comedi_set_hw_dev(comedi_dev, hardware_device);
468 comedi_dev->driver = driver;
469 ret = driver->auto_attach(comedi_dev, context);
471 module_put(driver->module);
472 __comedi_device_detach(comedi_dev);
474 ret = comedi_device_postconfig(comedi_dev);
477 mutex_unlock(&comedi_dev->mutex);
480 comedi_free_board_minor(minor);
483 EXPORT_SYMBOL_GPL(comedi_auto_config);
485 void comedi_auto_unconfig(struct device *hardware_device)
489 if (hardware_device == NULL)
491 minor = comedi_find_board_minor(hardware_device);
494 comedi_free_board_minor(minor);
496 EXPORT_SYMBOL_GPL(comedi_auto_unconfig);
498 #if IS_ENABLED(CONFIG_PCMCIA)
499 int comedi_pcmcia_driver_register(struct comedi_driver *comedi_driver,
500 struct pcmcia_driver *pcmcia_driver)
504 ret = comedi_driver_register(comedi_driver);
508 ret = pcmcia_register_driver(pcmcia_driver);
510 comedi_driver_unregister(comedi_driver);
516 EXPORT_SYMBOL_GPL(comedi_pcmcia_driver_register);
518 void comedi_pcmcia_driver_unregister(struct comedi_driver *comedi_driver,
519 struct pcmcia_driver *pcmcia_driver)
521 pcmcia_unregister_driver(pcmcia_driver);
522 comedi_driver_unregister(comedi_driver);
524 EXPORT_SYMBOL_GPL(comedi_pcmcia_driver_unregister);