1 /* The industrial I/O core
3 * Copyright (c) 2008 Jonathan Cameron
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
9 * Handling of buffer allocation / resizing.
12 * Things to look at here.
13 * - Better memory allocation techniques?
14 * - Alternative access techniques?
16 #include <linux/kernel.h>
17 #include <linux/export.h>
18 #include <linux/device.h>
20 #include <linux/cdev.h>
21 #include <linux/slab.h>
22 #include <linux/poll.h>
24 #include <linux/iio/iio.h>
26 #include <linux/iio/sysfs.h>
27 #include <linux/iio/buffer.h>
29 static const char * const iio_endian_prefix
[] = {
34 static bool iio_buffer_is_active(struct iio_dev
*indio_dev
,
35 struct iio_buffer
*buf
)
39 list_for_each(p
, &indio_dev
->buffer_list
)
40 if (p
== &buf
->buffer_list
)
47 * iio_buffer_read_first_n_outer() - chrdev read for buffer access
49 * This function relies on all buffer implementations having an
50 * iio_buffer as their first element.
52 ssize_t
iio_buffer_read_first_n_outer(struct file
*filp
, char __user
*buf
,
53 size_t n
, loff_t
*f_ps
)
55 struct iio_dev
*indio_dev
= filp
->private_data
;
56 struct iio_buffer
*rb
= indio_dev
->buffer
;
58 if (!rb
|| !rb
->access
->read_first_n
)
60 return rb
->access
->read_first_n(rb
, n
, buf
);
64 * iio_buffer_poll() - poll the buffer to find out if it has data
66 unsigned int iio_buffer_poll(struct file
*filp
,
67 struct poll_table_struct
*wait
)
69 struct iio_dev
*indio_dev
= filp
->private_data
;
70 struct iio_buffer
*rb
= indio_dev
->buffer
;
72 poll_wait(filp
, &rb
->pollq
, wait
);
74 return POLLIN
| POLLRDNORM
;
75 /* need a way of knowing if there may be enough data... */
79 void iio_buffer_init(struct iio_buffer
*buffer
)
81 INIT_LIST_HEAD(&buffer
->demux_list
);
82 init_waitqueue_head(&buffer
->pollq
);
84 EXPORT_SYMBOL(iio_buffer_init
);
86 static ssize_t
iio_show_scan_index(struct device
*dev
,
87 struct device_attribute
*attr
,
90 return sprintf(buf
, "%u\n", to_iio_dev_attr(attr
)->c
->scan_index
);
93 static ssize_t
iio_show_fixed_type(struct device
*dev
,
94 struct device_attribute
*attr
,
97 struct iio_dev_attr
*this_attr
= to_iio_dev_attr(attr
);
98 u8 type
= this_attr
->c
->scan_type
.endianness
;
100 if (type
== IIO_CPU
) {
101 #ifdef __LITTLE_ENDIAN
107 return sprintf(buf
, "%s:%c%d/%d>>%u\n",
108 iio_endian_prefix
[type
],
109 this_attr
->c
->scan_type
.sign
,
110 this_attr
->c
->scan_type
.realbits
,
111 this_attr
->c
->scan_type
.storagebits
,
112 this_attr
->c
->scan_type
.shift
);
115 static ssize_t
iio_scan_el_show(struct device
*dev
,
116 struct device_attribute
*attr
,
120 struct iio_dev
*indio_dev
= dev_to_iio_dev(dev
);
122 ret
= test_bit(to_iio_dev_attr(attr
)->address
,
123 indio_dev
->buffer
->scan_mask
);
125 return sprintf(buf
, "%d\n", ret
);
128 static int iio_scan_mask_clear(struct iio_buffer
*buffer
, int bit
)
130 clear_bit(bit
, buffer
->scan_mask
);
134 static ssize_t
iio_scan_el_store(struct device
*dev
,
135 struct device_attribute
*attr
,
141 struct iio_dev
*indio_dev
= dev_to_iio_dev(dev
);
142 struct iio_buffer
*buffer
= indio_dev
->buffer
;
143 struct iio_dev_attr
*this_attr
= to_iio_dev_attr(attr
);
145 ret
= strtobool(buf
, &state
);
148 mutex_lock(&indio_dev
->mlock
);
149 if (iio_buffer_is_active(indio_dev
, indio_dev
->buffer
)) {
153 ret
= iio_scan_mask_query(indio_dev
, buffer
, this_attr
->address
);
157 ret
= iio_scan_mask_clear(buffer
, this_attr
->address
);
160 } else if (state
&& !ret
) {
161 ret
= iio_scan_mask_set(indio_dev
, buffer
, this_attr
->address
);
167 mutex_unlock(&indio_dev
->mlock
);
169 return ret
< 0 ? ret
: len
;
173 static ssize_t
iio_scan_el_ts_show(struct device
*dev
,
174 struct device_attribute
*attr
,
177 struct iio_dev
*indio_dev
= dev_to_iio_dev(dev
);
178 return sprintf(buf
, "%d\n", indio_dev
->buffer
->scan_timestamp
);
181 static ssize_t
iio_scan_el_ts_store(struct device
*dev
,
182 struct device_attribute
*attr
,
187 struct iio_dev
*indio_dev
= dev_to_iio_dev(dev
);
190 ret
= strtobool(buf
, &state
);
194 mutex_lock(&indio_dev
->mlock
);
195 if (iio_buffer_is_active(indio_dev
, indio_dev
->buffer
)) {
199 indio_dev
->buffer
->scan_timestamp
= state
;
201 mutex_unlock(&indio_dev
->mlock
);
203 return ret
? ret
: len
;
206 static int iio_buffer_add_channel_sysfs(struct iio_dev
*indio_dev
,
207 const struct iio_chan_spec
*chan
)
209 int ret
, attrcount
= 0;
210 struct iio_buffer
*buffer
= indio_dev
->buffer
;
212 ret
= __iio_add_chan_devattr("index",
214 &iio_show_scan_index
,
219 &buffer
->scan_el_dev_attr_list
);
223 ret
= __iio_add_chan_devattr("type",
225 &iio_show_fixed_type
,
230 &buffer
->scan_el_dev_attr_list
);
234 if (chan
->type
!= IIO_TIMESTAMP
)
235 ret
= __iio_add_chan_devattr("en",
242 &buffer
->scan_el_dev_attr_list
);
244 ret
= __iio_add_chan_devattr("en",
246 &iio_scan_el_ts_show
,
247 &iio_scan_el_ts_store
,
251 &buffer
->scan_el_dev_attr_list
);
258 static void iio_buffer_remove_and_free_scan_dev_attr(struct iio_dev
*indio_dev
,
259 struct iio_dev_attr
*p
)
261 kfree(p
->dev_attr
.attr
.name
);
265 static void __iio_buffer_attr_cleanup(struct iio_dev
*indio_dev
)
267 struct iio_dev_attr
*p
, *n
;
268 struct iio_buffer
*buffer
= indio_dev
->buffer
;
270 list_for_each_entry_safe(p
, n
,
271 &buffer
->scan_el_dev_attr_list
, l
)
272 iio_buffer_remove_and_free_scan_dev_attr(indio_dev
, p
);
275 static const char * const iio_scan_elements_group_name
= "scan_elements";
277 int iio_buffer_register(struct iio_dev
*indio_dev
,
278 const struct iio_chan_spec
*channels
,
281 struct iio_dev_attr
*p
;
282 struct attribute
**attr
;
283 struct iio_buffer
*buffer
= indio_dev
->buffer
;
284 int ret
, i
, attrn
, attrcount
, attrcount_orig
= 0;
287 indio_dev
->groups
[indio_dev
->groupcounter
++] = buffer
->attrs
;
289 if (buffer
->scan_el_attrs
!= NULL
) {
290 attr
= buffer
->scan_el_attrs
->attrs
;
291 while (*attr
++ != NULL
)
294 attrcount
= attrcount_orig
;
295 INIT_LIST_HEAD(&buffer
->scan_el_dev_attr_list
);
298 for (i
= 0; i
< num_channels
; i
++) {
299 if (channels
[i
].scan_index
< 0)
302 /* Establish necessary mask length */
303 if (channels
[i
].scan_index
>
304 (int)indio_dev
->masklength
- 1)
305 indio_dev
->masklength
306 = channels
[i
].scan_index
+ 1;
308 ret
= iio_buffer_add_channel_sysfs(indio_dev
,
311 goto error_cleanup_dynamic
;
313 if (channels
[i
].type
== IIO_TIMESTAMP
)
314 indio_dev
->scan_index_timestamp
=
315 channels
[i
].scan_index
;
317 if (indio_dev
->masklength
&& buffer
->scan_mask
== NULL
) {
318 buffer
->scan_mask
= kcalloc(BITS_TO_LONGS(indio_dev
->masklength
),
319 sizeof(*buffer
->scan_mask
),
321 if (buffer
->scan_mask
== NULL
) {
323 goto error_cleanup_dynamic
;
328 buffer
->scan_el_group
.name
= iio_scan_elements_group_name
;
330 buffer
->scan_el_group
.attrs
= kcalloc(attrcount
+ 1,
331 sizeof(buffer
->scan_el_group
.attrs
[0]),
333 if (buffer
->scan_el_group
.attrs
== NULL
) {
335 goto error_free_scan_mask
;
337 if (buffer
->scan_el_attrs
)
338 memcpy(buffer
->scan_el_group
.attrs
, buffer
->scan_el_attrs
,
339 sizeof(buffer
->scan_el_group
.attrs
[0])*attrcount_orig
);
340 attrn
= attrcount_orig
;
342 list_for_each_entry(p
, &buffer
->scan_el_dev_attr_list
, l
)
343 buffer
->scan_el_group
.attrs
[attrn
++] = &p
->dev_attr
.attr
;
344 indio_dev
->groups
[indio_dev
->groupcounter
++] = &buffer
->scan_el_group
;
348 error_free_scan_mask
:
349 kfree(buffer
->scan_mask
);
350 error_cleanup_dynamic
:
351 __iio_buffer_attr_cleanup(indio_dev
);
355 EXPORT_SYMBOL(iio_buffer_register
);
357 void iio_buffer_unregister(struct iio_dev
*indio_dev
)
359 kfree(indio_dev
->buffer
->scan_mask
);
360 kfree(indio_dev
->buffer
->scan_el_group
.attrs
);
361 __iio_buffer_attr_cleanup(indio_dev
);
363 EXPORT_SYMBOL(iio_buffer_unregister
);
365 ssize_t
iio_buffer_read_length(struct device
*dev
,
366 struct device_attribute
*attr
,
369 struct iio_dev
*indio_dev
= dev_to_iio_dev(dev
);
370 struct iio_buffer
*buffer
= indio_dev
->buffer
;
372 if (buffer
->access
->get_length
)
373 return sprintf(buf
, "%d\n",
374 buffer
->access
->get_length(buffer
));
378 EXPORT_SYMBOL(iio_buffer_read_length
);
380 ssize_t
iio_buffer_write_length(struct device
*dev
,
381 struct device_attribute
*attr
,
385 struct iio_dev
*indio_dev
= dev_to_iio_dev(dev
);
386 struct iio_buffer
*buffer
= indio_dev
->buffer
;
390 ret
= kstrtouint(buf
, 10, &val
);
394 if (buffer
->access
->get_length
)
395 if (val
== buffer
->access
->get_length(buffer
))
398 mutex_lock(&indio_dev
->mlock
);
399 if (iio_buffer_is_active(indio_dev
, indio_dev
->buffer
)) {
402 if (buffer
->access
->set_length
)
403 buffer
->access
->set_length(buffer
, val
);
406 mutex_unlock(&indio_dev
->mlock
);
408 return ret
? ret
: len
;
410 EXPORT_SYMBOL(iio_buffer_write_length
);
412 ssize_t
iio_buffer_show_enable(struct device
*dev
,
413 struct device_attribute
*attr
,
416 struct iio_dev
*indio_dev
= dev_to_iio_dev(dev
);
417 return sprintf(buf
, "%d\n",
418 iio_buffer_is_active(indio_dev
,
421 EXPORT_SYMBOL(iio_buffer_show_enable
);
423 /* note NULL used as error indicator as it doesn't make sense. */
424 static const unsigned long *iio_scan_mask_match(const unsigned long *av_masks
,
425 unsigned int masklength
,
426 const unsigned long *mask
)
428 if (bitmap_empty(mask
, masklength
))
431 if (bitmap_subset(mask
, av_masks
, masklength
))
433 av_masks
+= BITS_TO_LONGS(masklength
);
438 static int iio_compute_scan_bytes(struct iio_dev
*indio_dev
, const long *mask
,
441 const struct iio_chan_spec
*ch
;
445 /* How much space will the demuxed element take? */
446 for_each_set_bit(i
, mask
,
447 indio_dev
->masklength
) {
448 ch
= iio_find_channel_from_si(indio_dev
, i
);
449 length
= ch
->scan_type
.storagebits
/ 8;
450 bytes
= ALIGN(bytes
, length
);
454 ch
= iio_find_channel_from_si(indio_dev
,
455 indio_dev
->scan_index_timestamp
);
456 length
= ch
->scan_type
.storagebits
/ 8;
457 bytes
= ALIGN(bytes
, length
);
463 int iio_update_buffers(struct iio_dev
*indio_dev
,
464 struct iio_buffer
*insert_buffer
,
465 struct iio_buffer
*remove_buffer
)
469 struct iio_buffer
*buffer
;
470 unsigned long *compound_mask
;
471 const unsigned long *old_mask
;
473 /* Wind down existing buffers - iff there are any */
474 if (!list_empty(&indio_dev
->buffer_list
)) {
475 if (indio_dev
->setup_ops
->predisable
) {
476 ret
= indio_dev
->setup_ops
->predisable(indio_dev
);
480 indio_dev
->currentmode
= INDIO_DIRECT_MODE
;
481 if (indio_dev
->setup_ops
->postdisable
) {
482 ret
= indio_dev
->setup_ops
->postdisable(indio_dev
);
487 /* Keep a copy of current setup to allow roll back */
488 old_mask
= indio_dev
->active_scan_mask
;
489 if (!indio_dev
->available_scan_masks
)
490 indio_dev
->active_scan_mask
= NULL
;
493 list_del(&remove_buffer
->buffer_list
);
495 list_add(&insert_buffer
->buffer_list
, &indio_dev
->buffer_list
);
497 /* If no buffers in list, we are done */
498 if (list_empty(&indio_dev
->buffer_list
)) {
499 indio_dev
->currentmode
= INDIO_DIRECT_MODE
;
500 if (indio_dev
->available_scan_masks
== NULL
)
505 /* What scan mask do we actually have ?*/
506 compound_mask
= kcalloc(BITS_TO_LONGS(indio_dev
->masklength
),
507 sizeof(long), GFP_KERNEL
);
508 if (compound_mask
== NULL
) {
509 if (indio_dev
->available_scan_masks
== NULL
)
513 indio_dev
->scan_timestamp
= 0;
515 list_for_each_entry(buffer
, &indio_dev
->buffer_list
, buffer_list
) {
516 bitmap_or(compound_mask
, compound_mask
, buffer
->scan_mask
,
517 indio_dev
->masklength
);
518 indio_dev
->scan_timestamp
|= buffer
->scan_timestamp
;
520 if (indio_dev
->available_scan_masks
) {
521 indio_dev
->active_scan_mask
=
522 iio_scan_mask_match(indio_dev
->available_scan_masks
,
523 indio_dev
->masklength
,
525 if (indio_dev
->active_scan_mask
== NULL
) {
528 * Note can only occur when adding a buffer.
530 list_del(&insert_buffer
->buffer_list
);
531 indio_dev
->active_scan_mask
= old_mask
;
535 indio_dev
->active_scan_mask
= compound_mask
;
538 iio_update_demux(indio_dev
);
541 if (indio_dev
->setup_ops
->preenable
) {
542 ret
= indio_dev
->setup_ops
->preenable(indio_dev
);
545 "Buffer not started:"
546 "buffer preenable failed\n");
547 goto error_remove_inserted
;
550 indio_dev
->scan_bytes
=
551 iio_compute_scan_bytes(indio_dev
,
552 indio_dev
->active_scan_mask
,
553 indio_dev
->scan_timestamp
);
554 list_for_each_entry(buffer
, &indio_dev
->buffer_list
, buffer_list
)
555 if (buffer
->access
->request_update
) {
556 ret
= buffer
->access
->request_update(buffer
);
559 "Buffer not started:"
560 "buffer parameter update failed\n");
561 goto error_run_postdisable
;
564 if (indio_dev
->info
->update_scan_mode
) {
565 ret
= indio_dev
->info
566 ->update_scan_mode(indio_dev
,
567 indio_dev
->active_scan_mask
);
569 printk(KERN_INFO
"update scan mode failed\n");
570 goto error_run_postdisable
;
573 /* Definitely possible for devices to support both of these.*/
574 if (indio_dev
->modes
& INDIO_BUFFER_TRIGGERED
) {
575 if (!indio_dev
->trig
) {
576 printk(KERN_INFO
"Buffer not started: no trigger\n");
578 /* Can only occur on first buffer */
579 goto error_run_postdisable
;
581 indio_dev
->currentmode
= INDIO_BUFFER_TRIGGERED
;
582 } else if (indio_dev
->modes
& INDIO_BUFFER_HARDWARE
) {
583 indio_dev
->currentmode
= INDIO_BUFFER_HARDWARE
;
584 } else { /* should never be reached */
586 goto error_run_postdisable
;
589 if (indio_dev
->setup_ops
->postenable
) {
590 ret
= indio_dev
->setup_ops
->postenable(indio_dev
);
593 "Buffer not started: postenable failed\n");
594 indio_dev
->currentmode
= INDIO_DIRECT_MODE
;
595 if (indio_dev
->setup_ops
->postdisable
)
596 indio_dev
->setup_ops
->postdisable(indio_dev
);
597 goto error_disable_all_buffers
;
601 if (indio_dev
->available_scan_masks
)
602 kfree(compound_mask
);
608 error_disable_all_buffers
:
609 indio_dev
->currentmode
= INDIO_DIRECT_MODE
;
610 error_run_postdisable
:
611 if (indio_dev
->setup_ops
->postdisable
)
612 indio_dev
->setup_ops
->postdisable(indio_dev
);
613 error_remove_inserted
:
616 list_del(&insert_buffer
->buffer_list
);
617 indio_dev
->active_scan_mask
= old_mask
;
618 kfree(compound_mask
);
623 EXPORT_SYMBOL_GPL(iio_update_buffers
);
625 ssize_t
iio_buffer_store_enable(struct device
*dev
,
626 struct device_attribute
*attr
,
631 bool requested_state
;
632 struct iio_dev
*indio_dev
= dev_to_iio_dev(dev
);
633 struct iio_buffer
*pbuf
= indio_dev
->buffer
;
636 ret
= strtobool(buf
, &requested_state
);
640 mutex_lock(&indio_dev
->mlock
);
642 /* Find out if it is in the list */
643 inlist
= iio_buffer_is_active(indio_dev
, pbuf
);
644 /* Already in desired state */
645 if (inlist
== requested_state
)
649 ret
= iio_update_buffers(indio_dev
,
650 indio_dev
->buffer
, NULL
);
652 ret
= iio_update_buffers(indio_dev
,
653 NULL
, indio_dev
->buffer
);
658 mutex_unlock(&indio_dev
->mlock
);
659 return (ret
< 0) ? ret
: len
;
661 EXPORT_SYMBOL(iio_buffer_store_enable
);
663 int iio_sw_buffer_preenable(struct iio_dev
*indio_dev
)
665 struct iio_buffer
*buffer
;
667 dev_dbg(&indio_dev
->dev
, "%s\n", __func__
);
669 list_for_each_entry(buffer
, &indio_dev
->buffer_list
, buffer_list
)
670 if (buffer
->access
->set_bytes_per_datum
) {
671 bytes
= iio_compute_scan_bytes(indio_dev
,
673 buffer
->scan_timestamp
);
675 buffer
->access
->set_bytes_per_datum(buffer
, bytes
);
679 EXPORT_SYMBOL(iio_sw_buffer_preenable
);
682 * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected
683 * @indio_dev: the iio device
684 * @mask: scan mask to be checked
686 * Return true if exactly one bit is set in the scan mask, false otherwise. It
687 * can be used for devices where only one channel can be active for sampling at
690 bool iio_validate_scan_mask_onehot(struct iio_dev
*indio_dev
,
691 const unsigned long *mask
)
693 return bitmap_weight(mask
, indio_dev
->masklength
) == 1;
695 EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot
);
697 static bool iio_validate_scan_mask(struct iio_dev
*indio_dev
,
698 const unsigned long *mask
)
700 if (!indio_dev
->setup_ops
->validate_scan_mask
)
703 return indio_dev
->setup_ops
->validate_scan_mask(indio_dev
, mask
);
707 * iio_scan_mask_set() - set particular bit in the scan mask
708 * @buffer: the buffer whose scan mask we are interested in
709 * @bit: the bit to be set.
711 * Note that at this point we have no way of knowing what other
712 * buffers might request, hence this code only verifies that the
713 * individual buffers request is plausible.
715 int iio_scan_mask_set(struct iio_dev
*indio_dev
,
716 struct iio_buffer
*buffer
, int bit
)
718 const unsigned long *mask
;
719 unsigned long *trialmask
;
721 trialmask
= kmalloc(sizeof(*trialmask
)*
722 BITS_TO_LONGS(indio_dev
->masklength
),
725 if (trialmask
== NULL
)
727 if (!indio_dev
->masklength
) {
728 WARN_ON("trying to set scanmask prior to registering buffer\n");
729 goto err_invalid_mask
;
731 bitmap_copy(trialmask
, buffer
->scan_mask
, indio_dev
->masklength
);
732 set_bit(bit
, trialmask
);
734 if (!iio_validate_scan_mask(indio_dev
, trialmask
))
735 goto err_invalid_mask
;
737 if (indio_dev
->available_scan_masks
) {
738 mask
= iio_scan_mask_match(indio_dev
->available_scan_masks
,
739 indio_dev
->masklength
,
742 goto err_invalid_mask
;
744 bitmap_copy(buffer
->scan_mask
, trialmask
, indio_dev
->masklength
);
754 EXPORT_SYMBOL_GPL(iio_scan_mask_set
);
756 int iio_scan_mask_query(struct iio_dev
*indio_dev
,
757 struct iio_buffer
*buffer
, int bit
)
759 if (bit
> indio_dev
->masklength
)
762 if (!buffer
->scan_mask
)
765 return test_bit(bit
, buffer
->scan_mask
);
767 EXPORT_SYMBOL_GPL(iio_scan_mask_query
);
770 * struct iio_demux_table() - table describing demux memcpy ops
771 * @from: index to copy from
772 * @to: index to copy to
773 * @length: how many bytes to copy
774 * @l: list head used for management
776 struct iio_demux_table
{
783 static unsigned char *iio_demux(struct iio_buffer
*buffer
,
784 unsigned char *datain
)
786 struct iio_demux_table
*t
;
788 if (list_empty(&buffer
->demux_list
))
790 list_for_each_entry(t
, &buffer
->demux_list
, l
)
791 memcpy(buffer
->demux_bounce
+ t
->to
,
792 datain
+ t
->from
, t
->length
);
794 return buffer
->demux_bounce
;
797 static int iio_push_to_buffer(struct iio_buffer
*buffer
, unsigned char *data
)
799 unsigned char *dataout
= iio_demux(buffer
, data
);
801 return buffer
->access
->store_to(buffer
, dataout
);
804 static void iio_buffer_demux_free(struct iio_buffer
*buffer
)
806 struct iio_demux_table
*p
, *q
;
807 list_for_each_entry_safe(p
, q
, &buffer
->demux_list
, l
) {
814 int iio_push_to_buffers(struct iio_dev
*indio_dev
, unsigned char *data
)
817 struct iio_buffer
*buf
;
819 list_for_each_entry(buf
, &indio_dev
->buffer_list
, buffer_list
) {
820 ret
= iio_push_to_buffer(buf
, data
);
827 EXPORT_SYMBOL_GPL(iio_push_to_buffers
);
829 static int iio_buffer_update_demux(struct iio_dev
*indio_dev
,
830 struct iio_buffer
*buffer
)
832 const struct iio_chan_spec
*ch
;
833 int ret
, in_ind
= -1, out_ind
, length
;
834 unsigned in_loc
= 0, out_loc
= 0;
835 struct iio_demux_table
*p
;
837 /* Clear out any old demux */
838 iio_buffer_demux_free(buffer
);
839 kfree(buffer
->demux_bounce
);
840 buffer
->demux_bounce
= NULL
;
842 /* First work out which scan mode we will actually have */
843 if (bitmap_equal(indio_dev
->active_scan_mask
,
845 indio_dev
->masklength
))
848 /* Now we have the two masks, work from least sig and build up sizes */
849 for_each_set_bit(out_ind
,
850 indio_dev
->active_scan_mask
,
851 indio_dev
->masklength
) {
852 in_ind
= find_next_bit(indio_dev
->active_scan_mask
,
853 indio_dev
->masklength
,
855 while (in_ind
!= out_ind
) {
856 in_ind
= find_next_bit(indio_dev
->active_scan_mask
,
857 indio_dev
->masklength
,
859 ch
= iio_find_channel_from_si(indio_dev
, in_ind
);
860 length
= ch
->scan_type
.storagebits
/8;
861 /* Make sure we are aligned */
864 in_loc
+= length
- in_loc
% length
;
866 p
= kmalloc(sizeof(*p
), GFP_KERNEL
);
869 goto error_clear_mux_table
;
871 ch
= iio_find_channel_from_si(indio_dev
, in_ind
);
872 length
= ch
->scan_type
.storagebits
/8;
873 if (out_loc
% length
)
874 out_loc
+= length
- out_loc
% length
;
876 in_loc
+= length
- in_loc
% length
;
880 list_add_tail(&p
->l
, &buffer
->demux_list
);
884 /* Relies on scan_timestamp being last */
885 if (buffer
->scan_timestamp
) {
886 p
= kmalloc(sizeof(*p
), GFP_KERNEL
);
889 goto error_clear_mux_table
;
891 ch
= iio_find_channel_from_si(indio_dev
,
892 indio_dev
->scan_index_timestamp
);
893 length
= ch
->scan_type
.storagebits
/8;
894 if (out_loc
% length
)
895 out_loc
+= length
- out_loc
% length
;
897 in_loc
+= length
- in_loc
% length
;
901 list_add_tail(&p
->l
, &buffer
->demux_list
);
905 buffer
->demux_bounce
= kzalloc(out_loc
, GFP_KERNEL
);
906 if (buffer
->demux_bounce
== NULL
) {
908 goto error_clear_mux_table
;
912 error_clear_mux_table
:
913 iio_buffer_demux_free(buffer
);
918 int iio_update_demux(struct iio_dev
*indio_dev
)
920 struct iio_buffer
*buffer
;
923 list_for_each_entry(buffer
, &indio_dev
->buffer_list
, buffer_list
) {
924 ret
= iio_buffer_update_demux(indio_dev
, buffer
);
926 goto error_clear_mux_table
;
930 error_clear_mux_table
:
931 list_for_each_entry(buffer
, &indio_dev
->buffer_list
, buffer_list
)
932 iio_buffer_demux_free(buffer
);
936 EXPORT_SYMBOL_GPL(iio_update_demux
);