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/delay.h>
27 #include <linux/ioport.h>
29 #include <linux/slab.h>
30 #include <linux/highmem.h> /* for SuSE brokenness */
31 #include <linux/vmalloc.h>
32 #include <linux/cdev.h>
33 #include <linux/dma-mapping.h>
35 #include <linux/interrupt.h>
36 #include <linux/firmware.h>
38 #include "comedidev.h"
39 #include "comedi_internal.h"
41 struct comedi_driver *comedi_drivers;
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);
60 int comedi_alloc_subdevices(struct comedi_device *dev, int num_subdevices)
62 struct comedi_subdevice *s;
65 if (num_subdevices < 1)
68 s = kcalloc(num_subdevices, sizeof(*s), GFP_KERNEL);
72 dev->n_subdevices = num_subdevices;
74 for (i = 0; i < num_subdevices; ++i) {
75 s = &dev->subdevices[i];
78 s->async_dma_dir = DMA_NONE;
79 spin_lock_init(&s->spin_lock);
84 EXPORT_SYMBOL_GPL(comedi_alloc_subdevices);
86 static void cleanup_device(struct comedi_device *dev)
89 struct comedi_subdevice *s;
91 if (dev->subdevices) {
92 for (i = 0; i < dev->n_subdevices; i++) {
93 s = &dev->subdevices[i];
94 if (s->runflags & SRF_FREE_SPRIV)
96 comedi_free_subdevice_minor(s);
98 comedi_buf_alloc(dev, s, 0);
102 kfree(dev->subdevices);
103 dev->subdevices = NULL;
104 dev->n_subdevices = 0;
109 dev->board_name = NULL;
110 dev->board_ptr = NULL;
113 dev->ioenabled = false;
115 dev->read_subdev = NULL;
116 dev->write_subdev = NULL;
119 comedi_clear_hw_dev(dev);
122 void comedi_device_detach(struct comedi_device *dev)
124 dev->attached = false;
126 dev->driver->detach(dev);
130 static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s)
135 int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s,
136 struct comedi_insn *insn, unsigned int *data)
141 static int insn_rw_emulate_bits(struct comedi_device *dev,
142 struct comedi_subdevice *s,
143 struct comedi_insn *insn, unsigned int *data)
145 struct comedi_insn new_insn;
147 static const unsigned channels_per_bitfield = 32;
149 unsigned chan = CR_CHAN(insn->chanspec);
150 const unsigned base_bitfield_channel =
151 (chan < channels_per_bitfield) ? 0 : chan;
152 unsigned int new_data[2];
153 memset(new_data, 0, sizeof(new_data));
154 memset(&new_insn, 0, sizeof(new_insn));
155 new_insn.insn = INSN_BITS;
156 new_insn.chanspec = base_bitfield_channel;
158 new_insn.subdev = insn->subdev;
160 if (insn->insn == INSN_WRITE) {
161 if (!(s->subdev_flags & SDF_WRITABLE))
163 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */
164 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel))
168 ret = s->insn_bits(dev, s, &new_insn, new_data);
172 if (insn->insn == INSN_READ)
173 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1;
178 static int __comedi_device_postconfig_async(struct comedi_device *dev,
179 struct comedi_subdevice *s)
181 struct comedi_async *async;
182 unsigned int buf_size;
185 if ((s->subdev_flags & (SDF_CMD_READ | SDF_CMD_WRITE)) == 0) {
186 dev_warn(dev->class_dev,
187 "async subdevices must support SDF_CMD_READ or SDF_CMD_WRITE\n");
190 if (!s->do_cmdtest) {
191 dev_warn(dev->class_dev,
192 "async subdevices must have a do_cmdtest() function\n");
196 async = kzalloc(sizeof(*async), GFP_KERNEL);
200 init_waitqueue_head(&async->wait_head);
201 async->subdevice = s;
204 async->max_bufsize = comedi_default_buf_maxsize_kb * 1024;
205 buf_size = comedi_default_buf_size_kb * 1024;
206 if (buf_size > async->max_bufsize)
207 buf_size = async->max_bufsize;
209 if (comedi_buf_alloc(dev, s, buf_size) < 0) {
210 dev_warn(dev->class_dev, "Buffer allocation failed\n");
214 ret = s->buf_change(dev, s, buf_size);
219 comedi_alloc_subdevice_minor(s);
224 static int __comedi_device_postconfig(struct comedi_device *dev)
226 struct comedi_subdevice *s;
230 for (i = 0; i < dev->n_subdevices; i++) {
231 s = &dev->subdevices[i];
233 if (s->type == COMEDI_SUBD_UNUSED)
236 if (s->len_chanlist == 0)
240 ret = __comedi_device_postconfig_async(dev, s);
245 if (!s->range_table && !s->range_table_list)
246 s->range_table = &range_unknown;
248 if (!s->insn_read && s->insn_bits)
249 s->insn_read = insn_rw_emulate_bits;
250 if (!s->insn_write && s->insn_bits)
251 s->insn_write = insn_rw_emulate_bits;
254 s->insn_read = insn_inval;
256 s->insn_write = insn_inval;
258 s->insn_bits = insn_inval;
260 s->insn_config = insn_inval;
263 s->poll = poll_invalid;
269 /* do a little post-config cleanup */
270 static int comedi_device_postconfig(struct comedi_device *dev)
274 ret = __comedi_device_postconfig(dev);
278 dev->attached = true;
283 * Generic recognize function for drivers that register their supported
286 * 'driv->board_name' points to a 'const char *' member within the
287 * zeroth element of an array of some private board information
288 * structure, say 'struct foo_board' containing a member 'const char
289 * *board_name' that is initialized to point to a board name string that
290 * is one of the candidates matched against this function's 'name'
293 * 'driv->offset' is the size of the private board information
294 * structure, say 'sizeof(struct foo_board)', and 'driv->num_names' is
295 * the length of the array of private board information structures.
297 * If one of the board names in the array of private board information
298 * structures matches the name supplied to this function, the function
299 * returns a pointer to the pointer to the board name, otherwise it
300 * returns NULL. The return value ends up in the 'board_ptr' member of
301 * a 'struct comedi_device' that the low-level comedi driver's
302 * 'attach()' hook can convert to a point to a particular element of its
303 * array of private board information structures by subtracting the
304 * offset of the member that points to the board name. (No subtraction
305 * is required if the board name pointer is the first member of the
306 * private board information structure, which is generally the case.)
308 static void *comedi_recognize(struct comedi_driver *driv, const char *name)
310 char **name_ptr = (char **)driv->board_name;
313 for (i = 0; i < driv->num_names; i++) {
314 if (strcmp(*name_ptr, name) == 0)
316 name_ptr = (void *)name_ptr + driv->offset;
322 static void comedi_report_boards(struct comedi_driver *driv)
325 const char *const *name_ptr;
327 pr_info("comedi: valid board names for %s driver are:\n",
330 name_ptr = driv->board_name;
331 for (i = 0; i < driv->num_names; i++) {
332 pr_info(" %s\n", *name_ptr);
333 name_ptr = (const char **)((char *)name_ptr + driv->offset);
336 if (driv->num_names == 0)
337 pr_info(" %s\n", driv->driver_name);
341 * comedi_load_firmware() - Request and load firmware for a device.
342 * @dev: comedi_device struct
343 * @hw_device: device struct for the comedi_device
344 * @name: the name of the firmware image
345 * @cb: callback to the upload the firmware image
346 * @context: private context from the driver
348 int comedi_load_firmware(struct comedi_device *dev,
349 struct device *device,
351 int (*cb)(struct comedi_device *dev,
352 const u8 *data, size_t size,
353 unsigned long context),
354 unsigned long context)
356 const struct firmware *fw;
362 ret = request_firmware(&fw, name, device);
364 ret = cb(dev, fw->data, fw->size, context);
365 release_firmware(fw);
370 EXPORT_SYMBOL_GPL(comedi_load_firmware);
373 * __comedi_request_region() - Request an I/O reqion for a legacy driver.
374 * @dev: comedi_device struct
375 * @start: base address of the I/O reqion
376 * @len: length of the I/O region
378 int __comedi_request_region(struct comedi_device *dev,
379 unsigned long start, unsigned long len)
382 dev_warn(dev->class_dev,
383 "%s: a I/O base address must be specified\n",
388 if (!request_region(start, len, dev->board_name)) {
389 dev_warn(dev->class_dev, "%s: I/O port conflict (%#lx,%lu)\n",
390 dev->board_name, start, len);
396 EXPORT_SYMBOL_GPL(__comedi_request_region);
399 * comedi_request_region() - Request an I/O reqion for a legacy driver.
400 * @dev: comedi_device struct
401 * @start: base address of the I/O reqion
402 * @len: length of the I/O region
404 int comedi_request_region(struct comedi_device *dev,
405 unsigned long start, unsigned long len)
409 ret = __comedi_request_region(dev, start, len);
417 EXPORT_SYMBOL_GPL(comedi_request_region);
420 * comedi_legacy_detach() - A generic (*detach) function for legacy drivers.
421 * @dev: comedi_device struct
423 void comedi_legacy_detach(struct comedi_device *dev)
426 free_irq(dev->irq, dev);
429 if (dev->iobase && dev->iolen) {
430 release_region(dev->iobase, dev->iolen);
435 EXPORT_SYMBOL_GPL(comedi_legacy_detach);
437 int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it)
439 struct comedi_driver *driv;
445 for (driv = comedi_drivers; driv; driv = driv->next) {
446 if (!try_module_get(driv->module))
448 if (driv->num_names) {
449 dev->board_ptr = comedi_recognize(driv, it->board_name);
452 } else if (strcmp(driv->driver_name, it->board_name) == 0)
454 module_put(driv->module);
457 /* recognize has failed if we get here */
458 /* report valid board names before returning error */
459 for (driv = comedi_drivers; driv; driv = driv->next) {
460 if (!try_module_get(driv->module))
462 comedi_report_boards(driv);
463 module_put(driv->module);
467 if (driv->attach == NULL) {
468 /* driver does not support manual configuration */
469 dev_warn(dev->class_dev,
470 "driver '%s' does not support attach using comedi_config\n",
472 module_put(driv->module);
475 /* initialize dev->driver here so
476 * comedi_error() can be called from attach */
478 dev->board_name = dev->board_ptr ? *(const char **)dev->board_ptr
479 : dev->driver->driver_name;
480 ret = driv->attach(dev, it);
482 ret = comedi_device_postconfig(dev);
484 comedi_device_detach(dev);
485 module_put(driv->module);
487 /* On success, the driver module count has been incremented. */
491 int comedi_auto_config(struct device *hardware_device,
492 struct comedi_driver *driver, unsigned long context)
494 struct comedi_device *dev;
497 if (!hardware_device) {
498 pr_warn("BUG! comedi_auto_config called with NULL hardware_device\n");
502 dev_warn(hardware_device,
503 "BUG! comedi_auto_config called with NULL comedi driver\n");
507 if (!driver->auto_attach) {
508 dev_warn(hardware_device,
509 "BUG! comedi driver '%s' has no auto_attach handler\n",
510 driver->driver_name);
514 dev = comedi_alloc_board_minor(hardware_device);
517 /* Note: comedi_alloc_board_minor() locked dev->mutex. */
519 dev->driver = driver;
520 dev->board_name = dev->driver->driver_name;
521 ret = driver->auto_attach(dev, context);
523 ret = comedi_device_postconfig(dev);
525 comedi_device_detach(dev);
526 mutex_unlock(&dev->mutex);
529 comedi_release_hardware_device(hardware_device);
532 EXPORT_SYMBOL_GPL(comedi_auto_config);
534 void comedi_auto_unconfig(struct device *hardware_device)
536 if (hardware_device == NULL)
538 comedi_release_hardware_device(hardware_device);
540 EXPORT_SYMBOL_GPL(comedi_auto_unconfig);
542 int comedi_driver_register(struct comedi_driver *driver)
544 driver->next = comedi_drivers;
545 comedi_drivers = driver;
549 EXPORT_SYMBOL_GPL(comedi_driver_register);
551 int comedi_driver_unregister(struct comedi_driver *driver)
553 struct comedi_driver *prev;
556 /* check for devices using this driver */
557 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) {
558 struct comedi_device *dev = comedi_dev_from_minor(i);
563 mutex_lock(&dev->mutex);
564 if (dev->attached && dev->driver == driver) {
566 dev_warn(dev->class_dev,
567 "BUG! detaching device with use_count=%d\n",
569 comedi_device_detach(dev);
571 mutex_unlock(&dev->mutex);
574 if (comedi_drivers == driver) {
575 comedi_drivers = driver->next;
579 for (prev = comedi_drivers; prev->next; prev = prev->next) {
580 if (prev->next == driver) {
581 prev->next = driver->next;
587 EXPORT_SYMBOL_GPL(comedi_driver_unregister);