3 functions for manipulating drivers
5 COMEDI - Linux Control and Measurement Device Interface
6 Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
7 Copyright (C) 2002 Frank Mori Hess <fmhess@users.sourceforge.net>
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
20 #include <linux/device.h>
21 #include <linux/module.h>
22 #include <linux/errno.h>
23 #include <linux/kconfig.h>
24 #include <linux/kernel.h>
25 #include <linux/sched.h>
26 #include <linux/fcntl.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
;
42 /* protects access to comedi_drivers */
43 DEFINE_MUTEX(comedi_drivers_list_lock
);
45 int comedi_set_hw_dev(struct comedi_device
*dev
, struct device
*hw_dev
)
47 if (hw_dev
== dev
->hw_dev
)
49 if (dev
->hw_dev
!= NULL
)
51 dev
->hw_dev
= get_device(hw_dev
);
54 EXPORT_SYMBOL_GPL(comedi_set_hw_dev
);
56 static void comedi_clear_hw_dev(struct comedi_device
*dev
)
58 put_device(dev
->hw_dev
);
63 * comedi_alloc_devpriv() - Allocate memory for the device private data.
64 * @dev: comedi_device struct
65 * @size: size of the memory to allocate
67 void *comedi_alloc_devpriv(struct comedi_device
*dev
, size_t size
)
69 dev
->private = kzalloc(size
, GFP_KERNEL
);
72 EXPORT_SYMBOL_GPL(comedi_alloc_devpriv
);
74 int comedi_alloc_subdevices(struct comedi_device
*dev
, int num_subdevices
)
76 struct comedi_subdevice
*s
;
79 if (num_subdevices
< 1)
82 s
= kcalloc(num_subdevices
, sizeof(*s
), GFP_KERNEL
);
86 dev
->n_subdevices
= num_subdevices
;
88 for (i
= 0; i
< num_subdevices
; ++i
) {
89 s
= &dev
->subdevices
[i
];
92 s
->async_dma_dir
= DMA_NONE
;
93 spin_lock_init(&s
->spin_lock
);
98 EXPORT_SYMBOL_GPL(comedi_alloc_subdevices
);
101 * comedi_alloc_subdev_readback() - Allocate memory for the subdevice readback.
102 * @s: comedi_subdevice struct
104 int comedi_alloc_subdev_readback(struct comedi_subdevice
*s
)
109 s
->readback
= kcalloc(s
->n_chan
, sizeof(*s
->readback
), GFP_KERNEL
);
114 EXPORT_SYMBOL_GPL(comedi_alloc_subdev_readback
);
116 static void comedi_device_detach_cleanup(struct comedi_device
*dev
)
119 struct comedi_subdevice
*s
;
121 if (dev
->subdevices
) {
122 for (i
= 0; i
< dev
->n_subdevices
; i
++) {
123 s
= &dev
->subdevices
[i
];
124 if (s
->runflags
& SRF_FREE_SPRIV
)
126 comedi_free_subdevice_minor(s
);
128 comedi_buf_alloc(dev
, s
, 0);
133 kfree(dev
->subdevices
);
134 dev
->subdevices
= NULL
;
135 dev
->n_subdevices
= 0;
140 dev
->board_name
= NULL
;
141 dev
->board_ptr
= NULL
;
145 dev
->ioenabled
= false;
147 dev
->read_subdev
= NULL
;
148 dev
->write_subdev
= NULL
;
151 comedi_clear_hw_dev(dev
);
154 void comedi_device_detach(struct comedi_device
*dev
)
156 comedi_device_cancel_all(dev
);
157 down_write(&dev
->attach_lock
);
158 dev
->attached
= false;
161 dev
->driver
->detach(dev
);
162 comedi_device_detach_cleanup(dev
);
163 up_write(&dev
->attach_lock
);
166 static int poll_invalid(struct comedi_device
*dev
, struct comedi_subdevice
*s
)
171 int insn_inval(struct comedi_device
*dev
, struct comedi_subdevice
*s
,
172 struct comedi_insn
*insn
, unsigned int *data
)
178 * comedi_readback_insn_read() - A generic (*insn_read) for subdevice readback.
179 * @dev: comedi_device struct
180 * @s: comedi_subdevice struct
181 * @insn: comedi_insn struct
182 * @data: pointer to return the readback data
184 int comedi_readback_insn_read(struct comedi_device
*dev
,
185 struct comedi_subdevice
*s
,
186 struct comedi_insn
*insn
,
189 unsigned int chan
= CR_CHAN(insn
->chanspec
);
195 for (i
= 0; i
< insn
->n
; i
++)
196 data
[i
] = s
->readback
[chan
];
200 EXPORT_SYMBOL_GPL(comedi_readback_insn_read
);
203 * comedi_timeout() - busy-wait for a driver condition to occur.
204 * @dev: comedi_device struct
205 * @s: comedi_subdevice struct
206 * @insn: comedi_insn struct
207 * @cb: callback to check for the condition
208 * @context: private context from the driver
210 int comedi_timeout(struct comedi_device
*dev
,
211 struct comedi_subdevice
*s
,
212 struct comedi_insn
*insn
,
213 int (*cb
)(struct comedi_device
*dev
,
214 struct comedi_subdevice
*s
,
215 struct comedi_insn
*insn
,
216 unsigned long context
),
217 unsigned long context
)
219 unsigned long timeout
= jiffies
+ msecs_to_jiffies(COMEDI_TIMEOUT_MS
);
222 while (time_before(jiffies
, timeout
)) {
223 ret
= cb(dev
, s
, insn
, context
);
225 return ret
; /* success (0) or non EBUSY errno */
230 EXPORT_SYMBOL_GPL(comedi_timeout
);
233 * comedi_dio_insn_config() - boilerplate (*insn_config) for DIO subdevices.
234 * @dev: comedi_device struct
235 * @s: comedi_subdevice struct
236 * @insn: comedi_insn struct
237 * @data: parameters for the @insn
238 * @mask: io_bits mask for grouped channels
240 int comedi_dio_insn_config(struct comedi_device
*dev
,
241 struct comedi_subdevice
*s
,
242 struct comedi_insn
*insn
,
246 unsigned int chan_mask
= 1 << CR_CHAN(insn
->chanspec
);
252 case INSN_CONFIG_DIO_INPUT
:
256 case INSN_CONFIG_DIO_OUTPUT
:
260 case INSN_CONFIG_DIO_QUERY
:
261 data
[1] = (s
->io_bits
& mask
) ? COMEDI_OUTPUT
: COMEDI_INPUT
;
270 EXPORT_SYMBOL_GPL(comedi_dio_insn_config
);
273 * comedi_dio_update_state() - update the internal state of DIO subdevices.
274 * @s: comedi_subdevice struct
275 * @data: the channel mask and bits to update
277 unsigned int comedi_dio_update_state(struct comedi_subdevice
*s
,
280 unsigned int chanmask
= (s
->n_chan
< 32) ? ((1 << s
->n_chan
) - 1)
282 unsigned int mask
= data
[0] & chanmask
;
283 unsigned int bits
= data
[1];
287 s
->state
|= (bits
& mask
);
292 EXPORT_SYMBOL_GPL(comedi_dio_update_state
);
295 * comedi_bytes_per_scan - get length of asynchronous command "scan" in bytes
296 * @s: comedi_subdevice struct
298 * Determines the overall scan length according to the subdevice type and the
299 * number of channels in the scan.
301 * For digital input, output or input/output subdevices, samples for multiple
302 * channels are assumed to be packed into one or more unsigned short or
303 * unsigned int values according to the subdevice's SDF_LSAMPL flag. For other
304 * types of subdevice, samples are assumed to occupy a whole unsigned short or
305 * unsigned int according to the SDF_LSAMPL flag.
307 * Returns the overall scan length in bytes.
309 unsigned int comedi_bytes_per_scan(struct comedi_subdevice
*s
)
311 struct comedi_cmd
*cmd
= &s
->async
->cmd
;
312 unsigned int num_samples
;
313 unsigned int bits_per_sample
;
318 case COMEDI_SUBD_DIO
:
319 bits_per_sample
= 8 * bytes_per_sample(s
);
320 num_samples
= (cmd
->chanlist_len
+ bits_per_sample
- 1) /
324 num_samples
= cmd
->chanlist_len
;
327 return num_samples
* bytes_per_sample(s
);
329 EXPORT_SYMBOL_GPL(comedi_bytes_per_scan
);
332 * comedi_inc_scan_progress - update scan progress in asynchronous command
333 * @s: comedi_subdevice struct
334 * @num_bytes: amount of data in bytes to increment scan progress
336 * Increments the scan progress by the number of bytes specified by num_bytes.
337 * If the scan progress reaches or exceeds the scan length in bytes, reduce
338 * it modulo the scan length in bytes and set the "end of scan" asynchronous
339 * event flag to be processed later.
341 void comedi_inc_scan_progress(struct comedi_subdevice
*s
,
342 unsigned int num_bytes
)
344 struct comedi_async
*async
= s
->async
;
345 unsigned int scan_length
= comedi_bytes_per_scan(s
);
347 async
->scan_progress
+= num_bytes
;
348 if (async
->scan_progress
>= scan_length
) {
349 async
->scan_progress
%= scan_length
;
350 async
->events
|= COMEDI_CB_EOS
;
353 EXPORT_SYMBOL_GPL(comedi_inc_scan_progress
);
356 * comedi_handle_events - handle events and possibly stop acquisition
357 * @dev: comedi_device struct
358 * @s: comedi_subdevice struct
360 * Handles outstanding asynchronous acquisition event flags associated
361 * with the subdevice. Call the subdevice's "->cancel()" handler if the
362 * "end of acquisition", "error" or "overflow" event flags are set in order
363 * to stop the acquisition at the driver level.
365 * Calls comedi_event() to further process the event flags, which may mark
366 * the asynchronous command as no longer running, possibly terminated with
367 * an error, and may wake up tasks.
369 * Return a bit-mask of the handled events.
371 unsigned int comedi_handle_events(struct comedi_device
*dev
,
372 struct comedi_subdevice
*s
)
374 unsigned int events
= s
->async
->events
;
379 if (events
& (COMEDI_CB_EOA
| COMEDI_CB_ERROR
| COMEDI_CB_OVERFLOW
))
382 comedi_event(dev
, s
);
386 EXPORT_SYMBOL_GPL(comedi_handle_events
);
388 static int insn_rw_emulate_bits(struct comedi_device
*dev
,
389 struct comedi_subdevice
*s
,
390 struct comedi_insn
*insn
, unsigned int *data
)
392 struct comedi_insn new_insn
;
394 static const unsigned channels_per_bitfield
= 32;
396 unsigned chan
= CR_CHAN(insn
->chanspec
);
397 const unsigned base_bitfield_channel
=
398 (chan
< channels_per_bitfield
) ? 0 : chan
;
399 unsigned int new_data
[2];
401 memset(new_data
, 0, sizeof(new_data
));
402 memset(&new_insn
, 0, sizeof(new_insn
));
403 new_insn
.insn
= INSN_BITS
;
404 new_insn
.chanspec
= base_bitfield_channel
;
406 new_insn
.subdev
= insn
->subdev
;
408 if (insn
->insn
== INSN_WRITE
) {
409 if (!(s
->subdev_flags
& SDF_WRITABLE
))
411 new_data
[0] = 1 << (chan
- base_bitfield_channel
); /* mask */
412 new_data
[1] = data
[0] ? (1 << (chan
- base_bitfield_channel
))
416 ret
= s
->insn_bits(dev
, s
, &new_insn
, new_data
);
420 if (insn
->insn
== INSN_READ
)
421 data
[0] = (new_data
[1] >> (chan
- base_bitfield_channel
)) & 1;
426 static int __comedi_device_postconfig_async(struct comedi_device
*dev
,
427 struct comedi_subdevice
*s
)
429 struct comedi_async
*async
;
430 unsigned int buf_size
;
433 if ((s
->subdev_flags
& (SDF_CMD_READ
| SDF_CMD_WRITE
)) == 0) {
434 dev_warn(dev
->class_dev
,
435 "async subdevices must support SDF_CMD_READ or SDF_CMD_WRITE\n");
438 if (!s
->do_cmdtest
) {
439 dev_warn(dev
->class_dev
,
440 "async subdevices must have a do_cmdtest() function\n");
444 async
= kzalloc(sizeof(*async
), GFP_KERNEL
);
448 init_waitqueue_head(&async
->wait_head
);
451 async
->max_bufsize
= comedi_default_buf_maxsize_kb
* 1024;
452 buf_size
= comedi_default_buf_size_kb
* 1024;
453 if (buf_size
> async
->max_bufsize
)
454 buf_size
= async
->max_bufsize
;
456 if (comedi_buf_alloc(dev
, s
, buf_size
) < 0) {
457 dev_warn(dev
->class_dev
, "Buffer allocation failed\n");
461 ret
= s
->buf_change(dev
, s
);
466 comedi_alloc_subdevice_minor(s
);
471 static int __comedi_device_postconfig(struct comedi_device
*dev
)
473 struct comedi_subdevice
*s
;
477 for (i
= 0; i
< dev
->n_subdevices
; i
++) {
478 s
= &dev
->subdevices
[i
];
480 if (s
->type
== COMEDI_SUBD_UNUSED
)
483 if (s
->type
== COMEDI_SUBD_DO
) {
485 s
->io_bits
= (1 << s
->n_chan
) - 1;
487 s
->io_bits
= 0xffffffff;
490 if (s
->len_chanlist
== 0)
494 ret
= __comedi_device_postconfig_async(dev
, s
);
499 if (!s
->range_table
&& !s
->range_table_list
)
500 s
->range_table
= &range_unknown
;
502 if (!s
->insn_read
&& s
->insn_bits
)
503 s
->insn_read
= insn_rw_emulate_bits
;
504 if (!s
->insn_write
&& s
->insn_bits
)
505 s
->insn_write
= insn_rw_emulate_bits
;
508 s
->insn_read
= insn_inval
;
510 s
->insn_write
= insn_inval
;
512 s
->insn_bits
= insn_inval
;
514 s
->insn_config
= insn_inval
;
517 s
->poll
= poll_invalid
;
523 /* do a little post-config cleanup */
524 static int comedi_device_postconfig(struct comedi_device
*dev
)
528 ret
= __comedi_device_postconfig(dev
);
531 down_write(&dev
->attach_lock
);
532 dev
->attached
= true;
533 up_write(&dev
->attach_lock
);
538 * Generic recognize function for drivers that register their supported
541 * 'driv->board_name' points to a 'const char *' member within the
542 * zeroth element of an array of some private board information
543 * structure, say 'struct foo_board' containing a member 'const char
544 * *board_name' that is initialized to point to a board name string that
545 * is one of the candidates matched against this function's 'name'
548 * 'driv->offset' is the size of the private board information
549 * structure, say 'sizeof(struct foo_board)', and 'driv->num_names' is
550 * the length of the array of private board information structures.
552 * If one of the board names in the array of private board information
553 * structures matches the name supplied to this function, the function
554 * returns a pointer to the pointer to the board name, otherwise it
555 * returns NULL. The return value ends up in the 'board_ptr' member of
556 * a 'struct comedi_device' that the low-level comedi driver's
557 * 'attach()' hook can convert to a point to a particular element of its
558 * array of private board information structures by subtracting the
559 * offset of the member that points to the board name. (No subtraction
560 * is required if the board name pointer is the first member of the
561 * private board information structure, which is generally the case.)
563 static void *comedi_recognize(struct comedi_driver
*driv
, const char *name
)
565 char **name_ptr
= (char **)driv
->board_name
;
568 for (i
= 0; i
< driv
->num_names
; i
++) {
569 if (strcmp(*name_ptr
, name
) == 0)
571 name_ptr
= (void *)name_ptr
+ driv
->offset
;
577 static void comedi_report_boards(struct comedi_driver
*driv
)
580 const char *const *name_ptr
;
582 pr_info("comedi: valid board names for %s driver are:\n",
585 name_ptr
= driv
->board_name
;
586 for (i
= 0; i
< driv
->num_names
; i
++) {
587 pr_info(" %s\n", *name_ptr
);
588 name_ptr
= (const char **)((char *)name_ptr
+ driv
->offset
);
591 if (driv
->num_names
== 0)
592 pr_info(" %s\n", driv
->driver_name
);
596 * comedi_load_firmware() - Request and load firmware for a device.
597 * @dev: comedi_device struct
598 * @hw_device: device struct for the comedi_device
599 * @name: the name of the firmware image
600 * @cb: callback to the upload the firmware image
601 * @context: private context from the driver
603 int comedi_load_firmware(struct comedi_device
*dev
,
604 struct device
*device
,
606 int (*cb
)(struct comedi_device
*dev
,
607 const u8
*data
, size_t size
,
608 unsigned long context
),
609 unsigned long context
)
611 const struct firmware
*fw
;
617 ret
= request_firmware(&fw
, name
, device
);
619 ret
= cb(dev
, fw
->data
, fw
->size
, context
);
620 release_firmware(fw
);
623 return ret
< 0 ? ret
: 0;
625 EXPORT_SYMBOL_GPL(comedi_load_firmware
);
628 * __comedi_request_region() - Request an I/O reqion for a legacy driver.
629 * @dev: comedi_device struct
630 * @start: base address of the I/O reqion
631 * @len: length of the I/O region
633 int __comedi_request_region(struct comedi_device
*dev
,
634 unsigned long start
, unsigned long len
)
637 dev_warn(dev
->class_dev
,
638 "%s: a I/O base address must be specified\n",
643 if (!request_region(start
, len
, dev
->board_name
)) {
644 dev_warn(dev
->class_dev
, "%s: I/O port conflict (%#lx,%lu)\n",
645 dev
->board_name
, start
, len
);
651 EXPORT_SYMBOL_GPL(__comedi_request_region
);
654 * comedi_request_region() - Request an I/O reqion for a legacy driver.
655 * @dev: comedi_device struct
656 * @start: base address of the I/O reqion
657 * @len: length of the I/O region
659 int comedi_request_region(struct comedi_device
*dev
,
660 unsigned long start
, unsigned long len
)
664 ret
= __comedi_request_region(dev
, start
, len
);
672 EXPORT_SYMBOL_GPL(comedi_request_region
);
675 * comedi_legacy_detach() - A generic (*detach) function for legacy drivers.
676 * @dev: comedi_device struct
678 void comedi_legacy_detach(struct comedi_device
*dev
)
681 free_irq(dev
->irq
, dev
);
684 if (dev
->iobase
&& dev
->iolen
) {
685 release_region(dev
->iobase
, dev
->iolen
);
690 EXPORT_SYMBOL_GPL(comedi_legacy_detach
);
692 int comedi_device_attach(struct comedi_device
*dev
, struct comedi_devconfig
*it
)
694 struct comedi_driver
*driv
;
700 mutex_lock(&comedi_drivers_list_lock
);
701 for (driv
= comedi_drivers
; driv
; driv
= driv
->next
) {
702 if (!try_module_get(driv
->module
))
704 if (driv
->num_names
) {
705 dev
->board_ptr
= comedi_recognize(driv
, it
->board_name
);
708 } else if (strcmp(driv
->driver_name
, it
->board_name
) == 0) {
711 module_put(driv
->module
);
714 /* recognize has failed if we get here */
715 /* report valid board names before returning error */
716 for (driv
= comedi_drivers
; driv
; driv
= driv
->next
) {
717 if (!try_module_get(driv
->module
))
719 comedi_report_boards(driv
);
720 module_put(driv
->module
);
725 if (driv
->attach
== NULL
) {
726 /* driver does not support manual configuration */
727 dev_warn(dev
->class_dev
,
728 "driver '%s' does not support attach using comedi_config\n",
730 module_put(driv
->module
);
735 dev
->board_name
= dev
->board_ptr
? *(const char **)dev
->board_ptr
736 : dev
->driver
->driver_name
;
737 ret
= driv
->attach(dev
, it
);
739 ret
= comedi_device_postconfig(dev
);
741 comedi_device_detach(dev
);
742 module_put(driv
->module
);
744 /* On success, the driver module count has been incremented. */
746 mutex_unlock(&comedi_drivers_list_lock
);
750 int comedi_auto_config(struct device
*hardware_device
,
751 struct comedi_driver
*driver
, unsigned long context
)
753 struct comedi_device
*dev
;
756 if (!hardware_device
) {
757 pr_warn("BUG! comedi_auto_config called with NULL hardware_device\n");
761 dev_warn(hardware_device
,
762 "BUG! comedi_auto_config called with NULL comedi driver\n");
766 if (!driver
->auto_attach
) {
767 dev_warn(hardware_device
,
768 "BUG! comedi driver '%s' has no auto_attach handler\n",
769 driver
->driver_name
);
773 dev
= comedi_alloc_board_minor(hardware_device
);
775 dev_warn(hardware_device
,
776 "driver '%s' could not create device.\n",
777 driver
->driver_name
);
780 /* Note: comedi_alloc_board_minor() locked dev->mutex. */
782 dev
->driver
= driver
;
783 dev
->board_name
= dev
->driver
->driver_name
;
784 ret
= driver
->auto_attach(dev
, context
);
786 ret
= comedi_device_postconfig(dev
);
787 mutex_unlock(&dev
->mutex
);
790 dev_warn(hardware_device
,
791 "driver '%s' failed to auto-configure device.\n",
792 driver
->driver_name
);
793 comedi_release_hardware_device(hardware_device
);
796 * class_dev should be set properly here
797 * after a successful auto config
799 dev_info(dev
->class_dev
,
800 "driver '%s' has successfully auto-configured '%s'.\n",
801 driver
->driver_name
, dev
->board_name
);
805 EXPORT_SYMBOL_GPL(comedi_auto_config
);
807 void comedi_auto_unconfig(struct device
*hardware_device
)
809 if (hardware_device
== NULL
)
811 comedi_release_hardware_device(hardware_device
);
813 EXPORT_SYMBOL_GPL(comedi_auto_unconfig
);
815 int comedi_driver_register(struct comedi_driver
*driver
)
817 mutex_lock(&comedi_drivers_list_lock
);
818 driver
->next
= comedi_drivers
;
819 comedi_drivers
= driver
;
820 mutex_unlock(&comedi_drivers_list_lock
);
824 EXPORT_SYMBOL_GPL(comedi_driver_register
);
826 void comedi_driver_unregister(struct comedi_driver
*driver
)
828 struct comedi_driver
*prev
;
831 /* unlink the driver */
832 mutex_lock(&comedi_drivers_list_lock
);
833 if (comedi_drivers
== driver
) {
834 comedi_drivers
= driver
->next
;
836 for (prev
= comedi_drivers
; prev
->next
; prev
= prev
->next
) {
837 if (prev
->next
== driver
) {
838 prev
->next
= driver
->next
;
843 mutex_unlock(&comedi_drivers_list_lock
);
845 /* check for devices using this driver */
846 for (i
= 0; i
< COMEDI_NUM_BOARD_MINORS
; i
++) {
847 struct comedi_device
*dev
= comedi_dev_get_from_minor(i
);
852 mutex_lock(&dev
->mutex
);
853 if (dev
->attached
&& dev
->driver
== driver
) {
855 dev_warn(dev
->class_dev
,
856 "BUG! detaching device with use_count=%d\n",
858 comedi_device_detach(dev
);
860 mutex_unlock(&dev
->mutex
);
864 EXPORT_SYMBOL_GPL(comedi_driver_unregister
);