Commit | Line | Data |
---|---|---|
ed9eccbe DS |
1 | /* |
2 | module/drivers.c | |
3 | functions for manipulating drivers | |
4 | ||
5 | COMEDI - Linux Control and Measurement Device Interface | |
6 | Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org> | |
7 | ||
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. | |
12 | ||
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. | |
17 | ||
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. | |
21 | ||
22 | */ | |
23 | ||
ed9eccbe DS |
24 | #include <linux/device.h> |
25 | #include <linux/module.h> | |
ed9eccbe | 26 | #include <linux/errno.h> |
78b10615 | 27 | #include <linux/kconfig.h> |
ed9eccbe DS |
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> | |
33 | #include <linux/mm.h> | |
34 | #include <linux/slab.h> | |
ed9eccbe DS |
35 | #include <linux/highmem.h> /* for SuSE brokenness */ |
36 | #include <linux/vmalloc.h> | |
37 | #include <linux/cdev.h> | |
38 | #include <linux/dma-mapping.h> | |
5617f9da | 39 | #include <linux/io.h> |
ed9eccbe | 40 | |
242e7ad9 | 41 | #include "comedidev.h" |
3a5fa275 | 42 | #include "comedi_internal.h" |
242e7ad9 | 43 | |
139dfbdf | 44 | struct comedi_driver *comedi_drivers; |
ed9eccbe | 45 | |
da717511 IA |
46 | int comedi_set_hw_dev(struct comedi_device *dev, struct device *hw_dev) |
47 | { | |
de06d7c6 IA |
48 | if (hw_dev == dev->hw_dev) |
49 | return 0; | |
50 | if (dev->hw_dev != NULL) | |
51 | return -EEXIST; | |
da717511 | 52 | dev->hw_dev = get_device(hw_dev); |
da717511 IA |
53 | return 0; |
54 | } | |
55 | EXPORT_SYMBOL_GPL(comedi_set_hw_dev); | |
56 | ||
de06d7c6 IA |
57 | static void comedi_clear_hw_dev(struct comedi_device *dev) |
58 | { | |
59 | put_device(dev->hw_dev); | |
60 | dev->hw_dev = NULL; | |
61 | } | |
62 | ||
8b9ba6e5 | 63 | int comedi_alloc_subdevices(struct comedi_device *dev, int num_subdevices) |
2f0b9d08 | 64 | { |
03afcf47 | 65 | struct comedi_subdevice *s; |
8b9ba6e5 | 66 | int i; |
2f0b9d08 | 67 | |
7f801c41 HS |
68 | if (num_subdevices < 1) |
69 | return -EINVAL; | |
03afcf47 HS |
70 | |
71 | s = kcalloc(num_subdevices, sizeof(*s), GFP_KERNEL); | |
72 | if (!s) | |
2f0b9d08 | 73 | return -ENOMEM; |
03afcf47 | 74 | dev->subdevices = s; |
fba1d0fa | 75 | dev->n_subdevices = num_subdevices; |
03afcf47 | 76 | |
2f0b9d08 | 77 | for (i = 0; i < num_subdevices; ++i) { |
5e4c58ce | 78 | s = &dev->subdevices[i]; |
03afcf47 | 79 | s->device = dev; |
90a35c15 | 80 | s->index = i; |
03afcf47 HS |
81 | s->async_dma_dir = DMA_NONE; |
82 | spin_lock_init(&s->spin_lock); | |
83 | s->minor = -1; | |
2f0b9d08 HS |
84 | } |
85 | return 0; | |
86 | } | |
87 | EXPORT_SYMBOL_GPL(comedi_alloc_subdevices); | |
88 | ||
71b5f4f1 | 89 | static void cleanup_device(struct comedi_device *dev) |
ed9eccbe DS |
90 | { |
91 | int i; | |
34c43922 | 92 | struct comedi_subdevice *s; |
ed9eccbe DS |
93 | |
94 | if (dev->subdevices) { | |
95 | for (i = 0; i < dev->n_subdevices; i++) { | |
5e4c58ce | 96 | s = &dev->subdevices[i]; |
ed9eccbe DS |
97 | comedi_free_subdevice_minor(s); |
98 | if (s->async) { | |
99 | comedi_buf_alloc(dev, s, 0); | |
100 | kfree(s->async); | |
101 | } | |
102 | } | |
103 | kfree(dev->subdevices); | |
104 | dev->subdevices = NULL; | |
105 | dev->n_subdevices = 0; | |
106 | } | |
dedd1325 BP |
107 | kfree(dev->private); |
108 | dev->private = NULL; | |
7029a874 | 109 | dev->driver = NULL; |
ed9eccbe DS |
110 | dev->board_name = NULL; |
111 | dev->board_ptr = NULL; | |
112 | dev->iobase = 0; | |
00ca6884 | 113 | dev->ioenabled = false; |
ed9eccbe DS |
114 | dev->irq = 0; |
115 | dev->read_subdev = NULL; | |
116 | dev->write_subdev = NULL; | |
117 | dev->open = NULL; | |
118 | dev->close = NULL; | |
de06d7c6 | 119 | comedi_clear_hw_dev(dev); |
ed9eccbe DS |
120 | } |
121 | ||
71b5f4f1 | 122 | static void __comedi_device_detach(struct comedi_device *dev) |
ed9eccbe | 123 | { |
a7401cdd | 124 | dev->attached = false; |
5617f9da | 125 | if (dev->driver) |
ed9eccbe | 126 | dev->driver->detach(dev); |
5617f9da | 127 | else |
4f870fe6 IA |
128 | dev_warn(dev->class_dev, |
129 | "BUG: dev->driver=NULL in comedi_device_detach()\n"); | |
ed9eccbe DS |
130 | cleanup_device(dev); |
131 | } | |
132 | ||
71b5f4f1 | 133 | void comedi_device_detach(struct comedi_device *dev) |
ed9eccbe DS |
134 | { |
135 | if (!dev->attached) | |
136 | return; | |
137 | __comedi_device_detach(dev); | |
138 | } | |
139 | ||
01fca378 | 140 | static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s) |
ed9eccbe | 141 | { |
01fca378 | 142 | return -EINVAL; |
ed9eccbe DS |
143 | } |
144 | ||
01fca378 HS |
145 | int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, |
146 | struct comedi_insn *insn, unsigned int *data) | |
ed9eccbe | 147 | { |
01fca378 | 148 | return -EINVAL; |
ed9eccbe DS |
149 | } |
150 | ||
01fca378 HS |
151 | static int insn_rw_emulate_bits(struct comedi_device *dev, |
152 | struct comedi_subdevice *s, | |
153 | struct comedi_insn *insn, unsigned int *data) | |
ed9eccbe | 154 | { |
01fca378 HS |
155 | struct comedi_insn new_insn; |
156 | int ret; | |
157 | static const unsigned channels_per_bitfield = 32; | |
ed9eccbe | 158 | |
01fca378 HS |
159 | unsigned chan = CR_CHAN(insn->chanspec); |
160 | const unsigned base_bitfield_channel = | |
161 | (chan < channels_per_bitfield) ? 0 : chan; | |
162 | unsigned int new_data[2]; | |
163 | memset(new_data, 0, sizeof(new_data)); | |
164 | memset(&new_insn, 0, sizeof(new_insn)); | |
165 | new_insn.insn = INSN_BITS; | |
166 | new_insn.chanspec = base_bitfield_channel; | |
167 | new_insn.n = 2; | |
168 | new_insn.subdev = insn->subdev; | |
ed9eccbe | 169 | |
01fca378 HS |
170 | if (insn->insn == INSN_WRITE) { |
171 | if (!(s->subdev_flags & SDF_WRITABLE)) | |
172 | return -EINVAL; | |
173 | new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */ | |
174 | new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) | |
175 | : 0; /* bits */ | |
ed9eccbe DS |
176 | } |
177 | ||
01fca378 HS |
178 | ret = s->insn_bits(dev, s, &new_insn, new_data); |
179 | if (ret < 0) | |
180 | return ret; | |
ed9eccbe | 181 | |
01fca378 HS |
182 | if (insn->insn == INSN_READ) |
183 | data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1; | |
184 | ||
185 | return 1; | |
ed9eccbe DS |
186 | } |
187 | ||
40f58a65 HS |
188 | static int __comedi_device_postconfig_async(struct comedi_device *dev, |
189 | struct comedi_subdevice *s) | |
190 | { | |
191 | struct comedi_async *async; | |
192 | unsigned int buf_size; | |
193 | int ret; | |
194 | ||
57b71c3e HS |
195 | if ((s->subdev_flags & (SDF_CMD_READ | SDF_CMD_WRITE)) == 0) { |
196 | dev_warn(dev->class_dev, | |
197 | "async subdevices must support SDF_CMD_READ or SDF_CMD_WRITE\n"); | |
198 | return -EINVAL; | |
199 | } | |
200 | if (!s->do_cmdtest) { | |
201 | dev_warn(dev->class_dev, | |
202 | "async subdevices must have a do_cmdtest() function\n"); | |
203 | return -EINVAL; | |
204 | } | |
40f58a65 HS |
205 | |
206 | async = kzalloc(sizeof(*async), GFP_KERNEL); | |
78110bb8 | 207 | if (!async) |
40f58a65 | 208 | return -ENOMEM; |
78110bb8 | 209 | |
40f58a65 HS |
210 | init_waitqueue_head(&async->wait_head); |
211 | async->subdevice = s; | |
212 | s->async = async; | |
213 | ||
214 | async->max_bufsize = comedi_default_buf_maxsize_kb * 1024; | |
215 | buf_size = comedi_default_buf_size_kb * 1024; | |
216 | if (buf_size > async->max_bufsize) | |
217 | buf_size = async->max_bufsize; | |
218 | ||
219 | if (comedi_buf_alloc(dev, s, buf_size) < 0) { | |
220 | dev_warn(dev->class_dev, "Buffer allocation failed\n"); | |
221 | return -ENOMEM; | |
222 | } | |
223 | if (s->buf_change) { | |
224 | ret = s->buf_change(dev, s, buf_size); | |
225 | if (ret < 0) | |
226 | return ret; | |
227 | } | |
228 | ||
f65cc544 | 229 | comedi_alloc_subdevice_minor(s); |
40f58a65 HS |
230 | |
231 | return 0; | |
232 | } | |
233 | ||
234 | static int __comedi_device_postconfig(struct comedi_device *dev) | |
ed9eccbe | 235 | { |
34c43922 | 236 | struct comedi_subdevice *s; |
ed9eccbe | 237 | int ret; |
40f58a65 | 238 | int i; |
ed9eccbe DS |
239 | |
240 | for (i = 0; i < dev->n_subdevices; i++) { | |
5e4c58ce | 241 | s = &dev->subdevices[i]; |
ed9eccbe DS |
242 | |
243 | if (s->type == COMEDI_SUBD_UNUSED) | |
244 | continue; | |
245 | ||
246 | if (s->len_chanlist == 0) | |
247 | s->len_chanlist = 1; | |
248 | ||
249 | if (s->do_cmd) { | |
40f58a65 HS |
250 | ret = __comedi_device_postconfig_async(dev, s); |
251 | if (ret) | |
252 | return ret; | |
ed9eccbe DS |
253 | } |
254 | ||
255 | if (!s->range_table && !s->range_table_list) | |
256 | s->range_table = &range_unknown; | |
257 | ||
258 | if (!s->insn_read && s->insn_bits) | |
259 | s->insn_read = insn_rw_emulate_bits; | |
260 | if (!s->insn_write && s->insn_bits) | |
261 | s->insn_write = insn_rw_emulate_bits; | |
262 | ||
263 | if (!s->insn_read) | |
264 | s->insn_read = insn_inval; | |
265 | if (!s->insn_write) | |
266 | s->insn_write = insn_inval; | |
267 | if (!s->insn_bits) | |
268 | s->insn_bits = insn_inval; | |
269 | if (!s->insn_config) | |
270 | s->insn_config = insn_inval; | |
271 | ||
272 | if (!s->poll) | |
273 | s->poll = poll_invalid; | |
274 | } | |
275 | ||
276 | return 0; | |
277 | } | |
278 | ||
01fca378 HS |
279 | /* do a little post-config cleanup */ |
280 | /* called with module refcount incremented, decrements it */ | |
281 | static int comedi_device_postconfig(struct comedi_device *dev) | |
282 | { | |
40f58a65 | 283 | int ret = __comedi_device_postconfig(dev); |
01fca378 HS |
284 | module_put(dev->driver->module); |
285 | if (ret < 0) { | |
286 | __comedi_device_detach(dev); | |
287 | return ret; | |
288 | } | |
289 | if (!dev->board_name) { | |
290 | dev_warn(dev->class_dev, "BUG: dev->board_name=NULL\n"); | |
291 | dev->board_name = "BUG"; | |
292 | } | |
293 | smp_wmb(); | |
a7401cdd | 294 | dev->attached = true; |
01fca378 HS |
295 | return 0; |
296 | } | |
297 | ||
4e2f002f IA |
298 | /* |
299 | * Generic recognize function for drivers that register their supported | |
300 | * board names. | |
301 | * | |
302 | * 'driv->board_name' points to a 'const char *' member within the | |
303 | * zeroth element of an array of some private board information | |
304 | * structure, say 'struct foo_board' containing a member 'const char | |
305 | * *board_name' that is initialized to point to a board name string that | |
306 | * is one of the candidates matched against this function's 'name' | |
307 | * parameter. | |
308 | * | |
309 | * 'driv->offset' is the size of the private board information | |
310 | * structure, say 'sizeof(struct foo_board)', and 'driv->num_names' is | |
311 | * the length of the array of private board information structures. | |
312 | * | |
313 | * If one of the board names in the array of private board information | |
314 | * structures matches the name supplied to this function, the function | |
315 | * returns a pointer to the pointer to the board name, otherwise it | |
316 | * returns NULL. The return value ends up in the 'board_ptr' member of | |
317 | * a 'struct comedi_device' that the low-level comedi driver's | |
318 | * 'attach()' hook can convert to a point to a particular element of its | |
319 | * array of private board information structures by subtracting the | |
320 | * offset of the member that points to the board name. (No subtraction | |
321 | * is required if the board name pointer is the first member of the | |
322 | * private board information structure, which is generally the case.) | |
323 | */ | |
7029a874 | 324 | static void *comedi_recognize(struct comedi_driver *driv, const char *name) |
ed9eccbe | 325 | { |
1c9de58a DC |
326 | char **name_ptr = (char **)driv->board_name; |
327 | int i; | |
328 | ||
ed9eccbe DS |
329 | for (i = 0; i < driv->num_names; i++) { |
330 | if (strcmp(*name_ptr, name) == 0) | |
1c9de58a DC |
331 | return name_ptr; |
332 | name_ptr = (void *)name_ptr + driv->offset; | |
ed9eccbe DS |
333 | } |
334 | ||
335 | return NULL; | |
336 | } | |
337 | ||
7029a874 | 338 | static void comedi_report_boards(struct comedi_driver *driv) |
ed9eccbe DS |
339 | { |
340 | unsigned int i; | |
341 | const char *const *name_ptr; | |
342 | ||
4f870fe6 IA |
343 | pr_info("comedi: valid board names for %s driver are:\n", |
344 | driv->driver_name); | |
ed9eccbe DS |
345 | |
346 | name_ptr = driv->board_name; | |
347 | for (i = 0; i < driv->num_names; i++) { | |
4f870fe6 | 348 | pr_info(" %s\n", *name_ptr); |
ed9eccbe DS |
349 | name_ptr = (const char **)((char *)name_ptr + driv->offset); |
350 | } | |
351 | ||
352 | if (driv->num_names == 0) | |
4f870fe6 | 353 | pr_info(" %s\n", driv->driver_name); |
ed9eccbe DS |
354 | } |
355 | ||
01fca378 | 356 | int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it) |
ed9eccbe | 357 | { |
01fca378 HS |
358 | struct comedi_driver *driv; |
359 | int ret; | |
360 | ||
361 | if (dev->attached) | |
362 | return -EBUSY; | |
363 | ||
364 | for (driv = comedi_drivers; driv; driv = driv->next) { | |
365 | if (!try_module_get(driv->module)) | |
366 | continue; | |
367 | if (driv->num_names) { | |
368 | dev->board_ptr = comedi_recognize(driv, it->board_name); | |
369 | if (dev->board_ptr) | |
370 | break; | |
371 | } else if (strcmp(driv->driver_name, it->board_name) == 0) | |
372 | break; | |
373 | module_put(driv->module); | |
374 | } | |
375 | if (driv == NULL) { | |
376 | /* recognize has failed if we get here */ | |
377 | /* report valid board names before returning error */ | |
378 | for (driv = comedi_drivers; driv; driv = driv->next) { | |
379 | if (!try_module_get(driv->module)) | |
380 | continue; | |
381 | comedi_report_boards(driv); | |
382 | module_put(driv->module); | |
383 | } | |
384 | return -EIO; | |
385 | } | |
386 | if (driv->attach == NULL) { | |
387 | /* driver does not support manual configuration */ | |
388 | dev_warn(dev->class_dev, | |
389 | "driver '%s' does not support attach using comedi_config\n", | |
390 | driv->driver_name); | |
391 | module_put(driv->module); | |
392 | return -ENOSYS; | |
393 | } | |
394 | /* initialize dev->driver here so | |
395 | * comedi_error() can be called from attach */ | |
396 | dev->driver = driv; | |
397 | ret = driv->attach(dev, it); | |
398 | if (ret < 0) { | |
399 | module_put(dev->driver->module); | |
400 | __comedi_device_detach(dev); | |
401 | return ret; | |
402 | } | |
403 | return comedi_device_postconfig(dev); | |
ed9eccbe DS |
404 | } |
405 | ||
a588da1d IA |
406 | int comedi_auto_config(struct device *hardware_device, |
407 | struct comedi_driver *driver, unsigned long context) | |
f4011670 IA |
408 | { |
409 | int minor; | |
f4011670 IA |
410 | struct comedi_device *comedi_dev; |
411 | int ret; | |
412 | ||
a588da1d IA |
413 | if (!driver->auto_attach) { |
414 | dev_warn(hardware_device, | |
415 | "BUG! comedi driver '%s' has no auto_attach handler\n", | |
416 | driver->driver_name); | |
417 | return -EINVAL; | |
418 | } | |
419 | ||
f4011670 IA |
420 | minor = comedi_alloc_board_minor(hardware_device); |
421 | if (minor < 0) | |
422 | return minor; | |
423 | ||
4da5fa9a | 424 | comedi_dev = comedi_dev_from_minor(minor); |
f4011670 IA |
425 | |
426 | mutex_lock(&comedi_dev->mutex); | |
427 | if (comedi_dev->attached) | |
428 | ret = -EBUSY; | |
4f870fe6 | 429 | else if (!try_module_get(driver->module)) |
f4011670 | 430 | ret = -EIO; |
4f870fe6 | 431 | else { |
26cbd465 | 432 | comedi_set_hw_dev(comedi_dev, hardware_device); |
f4011670 | 433 | comedi_dev->driver = driver; |
a588da1d | 434 | ret = driver->auto_attach(comedi_dev, context); |
f4011670 IA |
435 | if (ret < 0) { |
436 | module_put(driver->module); | |
437 | __comedi_device_detach(comedi_dev); | |
438 | } else { | |
439 | ret = comedi_device_postconfig(comedi_dev); | |
440 | } | |
441 | } | |
442 | mutex_unlock(&comedi_dev->mutex); | |
443 | ||
444 | if (ret < 0) | |
445 | comedi_free_board_minor(minor); | |
446 | return ret; | |
447 | } | |
8ed705af IA |
448 | EXPORT_SYMBOL_GPL(comedi_auto_config); |
449 | ||
450 | void comedi_auto_unconfig(struct device *hardware_device) | |
ed9eccbe | 451 | { |
c43435d7 | 452 | int minor; |
ed9eccbe | 453 | |
c43435d7 IA |
454 | if (hardware_device == NULL) |
455 | return; | |
456 | minor = comedi_find_board_minor(hardware_device); | |
457 | if (minor < 0) | |
458 | return; | |
c43435d7 | 459 | comedi_free_board_minor(minor); |
ed9eccbe | 460 | } |
8ed705af | 461 | EXPORT_SYMBOL_GPL(comedi_auto_unconfig); |
1ae6b20b HS |
462 | |
463 | int comedi_driver_register(struct comedi_driver *driver) | |
464 | { | |
465 | driver->next = comedi_drivers; | |
466 | comedi_drivers = driver; | |
467 | ||
468 | return 0; | |
469 | } | |
470 | EXPORT_SYMBOL(comedi_driver_register); | |
471 | ||
472 | int comedi_driver_unregister(struct comedi_driver *driver) | |
473 | { | |
474 | struct comedi_driver *prev; | |
475 | int i; | |
476 | ||
477 | /* check for devices using this driver */ | |
478 | for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { | |
479 | struct comedi_device *dev = comedi_dev_from_minor(i); | |
480 | ||
481 | if (!dev) | |
482 | continue; | |
483 | ||
484 | mutex_lock(&dev->mutex); | |
485 | if (dev->attached && dev->driver == driver) { | |
486 | if (dev->use_count) | |
487 | dev_warn(dev->class_dev, | |
488 | "BUG! detaching device with use_count=%d\n", | |
489 | dev->use_count); | |
490 | comedi_device_detach(dev); | |
491 | } | |
492 | mutex_unlock(&dev->mutex); | |
493 | } | |
494 | ||
495 | if (comedi_drivers == driver) { | |
496 | comedi_drivers = driver->next; | |
497 | return 0; | |
498 | } | |
499 | ||
500 | for (prev = comedi_drivers; prev->next; prev = prev->next) { | |
501 | if (prev->next == driver) { | |
502 | prev->next = driver->next; | |
503 | return 0; | |
504 | } | |
505 | } | |
506 | return -EINVAL; | |
507 | } | |
508 | EXPORT_SYMBOL(comedi_driver_unregister); |