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0464415dd2
Used to allow information about a given channel mapping to be passed through from board files to the consumer drivers. Signed-off-by: Jonathan Cameron <jic23@kernel.org>
411 lines
9.1 KiB
C
411 lines
9.1 KiB
C
/* The industrial I/O core in kernel channel mapping
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*
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* Copyright (c) 2011 Jonathan Cameron
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 as published by
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* the Free Software Foundation.
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*/
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#include <linux/err.h>
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#include <linux/export.h>
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#include <linux/slab.h>
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#include <linux/mutex.h>
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#include <linux/iio/iio.h>
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#include "iio_core.h"
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#include <linux/iio/machine.h>
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#include <linux/iio/driver.h>
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#include <linux/iio/consumer.h>
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struct iio_map_internal {
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struct iio_dev *indio_dev;
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struct iio_map *map;
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struct list_head l;
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};
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static LIST_HEAD(iio_map_list);
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static DEFINE_MUTEX(iio_map_list_lock);
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int iio_map_array_register(struct iio_dev *indio_dev, struct iio_map *maps)
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{
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int i = 0, ret = 0;
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struct iio_map_internal *mapi;
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if (maps == NULL)
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return 0;
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mutex_lock(&iio_map_list_lock);
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while (maps[i].consumer_dev_name != NULL) {
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mapi = kzalloc(sizeof(*mapi), GFP_KERNEL);
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if (mapi == NULL) {
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ret = -ENOMEM;
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goto error_ret;
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}
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mapi->map = &maps[i];
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mapi->indio_dev = indio_dev;
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list_add(&mapi->l, &iio_map_list);
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i++;
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}
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error_ret:
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mutex_unlock(&iio_map_list_lock);
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return ret;
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}
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EXPORT_SYMBOL_GPL(iio_map_array_register);
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/* Assumes the exact same array (e.g. memory locations)
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* used at unregistration as used at registration rather than
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* more complex checking of contents.
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*/
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int iio_map_array_unregister(struct iio_dev *indio_dev,
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struct iio_map *maps)
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{
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int i = 0, ret = 0;
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bool found_it;
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struct iio_map_internal *mapi;
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if (maps == NULL)
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return 0;
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mutex_lock(&iio_map_list_lock);
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while (maps[i].consumer_dev_name != NULL) {
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found_it = false;
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list_for_each_entry(mapi, &iio_map_list, l)
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if (&maps[i] == mapi->map) {
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list_del(&mapi->l);
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kfree(mapi);
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found_it = true;
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break;
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}
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if (!found_it) {
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ret = -ENODEV;
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goto error_ret;
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}
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i++;
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}
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error_ret:
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mutex_unlock(&iio_map_list_lock);
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return ret;
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}
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EXPORT_SYMBOL_GPL(iio_map_array_unregister);
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static const struct iio_chan_spec
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*iio_chan_spec_from_name(const struct iio_dev *indio_dev, const char *name)
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{
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int i;
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const struct iio_chan_spec *chan = NULL;
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for (i = 0; i < indio_dev->num_channels; i++)
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if (indio_dev->channels[i].datasheet_name &&
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strcmp(name, indio_dev->channels[i].datasheet_name) == 0) {
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chan = &indio_dev->channels[i];
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break;
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}
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return chan;
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}
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struct iio_channel *iio_channel_get(const char *name, const char *channel_name)
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{
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struct iio_map_internal *c_i = NULL, *c = NULL;
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struct iio_channel *channel;
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int err;
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if (name == NULL && channel_name == NULL)
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return ERR_PTR(-ENODEV);
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/* first find matching entry the channel map */
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mutex_lock(&iio_map_list_lock);
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list_for_each_entry(c_i, &iio_map_list, l) {
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if ((name && strcmp(name, c_i->map->consumer_dev_name) != 0) ||
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(channel_name &&
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strcmp(channel_name, c_i->map->consumer_channel) != 0))
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continue;
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c = c_i;
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iio_device_get(c->indio_dev);
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break;
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}
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mutex_unlock(&iio_map_list_lock);
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if (c == NULL)
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return ERR_PTR(-ENODEV);
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channel = kzalloc(sizeof(*channel), GFP_KERNEL);
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if (channel == NULL) {
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err = -ENOMEM;
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goto error_no_mem;
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}
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channel->indio_dev = c->indio_dev;
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if (c->map->adc_channel_label) {
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channel->channel =
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iio_chan_spec_from_name(channel->indio_dev,
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c->map->adc_channel_label);
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if (channel->channel == NULL) {
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err = -EINVAL;
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goto error_no_chan;
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}
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}
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return channel;
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error_no_chan:
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kfree(channel);
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error_no_mem:
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iio_device_put(c->indio_dev);
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return ERR_PTR(err);
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}
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EXPORT_SYMBOL_GPL(iio_channel_get);
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void iio_channel_release(struct iio_channel *channel)
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{
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iio_device_put(channel->indio_dev);
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kfree(channel);
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}
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EXPORT_SYMBOL_GPL(iio_channel_release);
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struct iio_channel *iio_channel_get_all(const char *name)
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{
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struct iio_channel *chans;
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struct iio_map_internal *c = NULL;
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int nummaps = 0;
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int mapind = 0;
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int i, ret;
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if (name == NULL)
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return ERR_PTR(-EINVAL);
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mutex_lock(&iio_map_list_lock);
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/* first count the matching maps */
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list_for_each_entry(c, &iio_map_list, l)
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if (name && strcmp(name, c->map->consumer_dev_name) != 0)
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continue;
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else
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nummaps++;
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if (nummaps == 0) {
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ret = -ENODEV;
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goto error_ret;
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}
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/* NULL terminated array to save passing size */
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chans = kzalloc(sizeof(*chans)*(nummaps + 1), GFP_KERNEL);
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if (chans == NULL) {
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ret = -ENOMEM;
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goto error_ret;
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}
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/* for each map fill in the chans element */
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list_for_each_entry(c, &iio_map_list, l) {
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if (name && strcmp(name, c->map->consumer_dev_name) != 0)
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continue;
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chans[mapind].indio_dev = c->indio_dev;
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chans[mapind].data = c->map->consumer_data;
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chans[mapind].channel =
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iio_chan_spec_from_name(chans[mapind].indio_dev,
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c->map->adc_channel_label);
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if (chans[mapind].channel == NULL) {
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ret = -EINVAL;
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goto error_free_chans;
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}
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iio_device_get(chans[mapind].indio_dev);
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mapind++;
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}
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if (mapind == 0) {
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ret = -ENODEV;
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goto error_free_chans;
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}
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mutex_unlock(&iio_map_list_lock);
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return chans;
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error_free_chans:
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for (i = 0; i < nummaps; i++)
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iio_device_put(chans[i].indio_dev);
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kfree(chans);
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error_ret:
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mutex_unlock(&iio_map_list_lock);
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return ERR_PTR(ret);
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}
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EXPORT_SYMBOL_GPL(iio_channel_get_all);
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void iio_channel_release_all(struct iio_channel *channels)
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{
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struct iio_channel *chan = &channels[0];
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while (chan->indio_dev) {
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iio_device_put(chan->indio_dev);
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chan++;
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}
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kfree(channels);
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}
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EXPORT_SYMBOL_GPL(iio_channel_release_all);
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static int iio_channel_read(struct iio_channel *chan, int *val, int *val2,
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enum iio_chan_info_enum info)
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{
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int unused;
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if (val2 == NULL)
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val2 = &unused;
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return chan->indio_dev->info->read_raw(chan->indio_dev, chan->channel,
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val, val2, info);
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}
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int iio_read_channel_raw(struct iio_channel *chan, int *val)
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{
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int ret;
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mutex_lock(&chan->indio_dev->info_exist_lock);
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if (chan->indio_dev->info == NULL) {
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ret = -ENODEV;
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goto err_unlock;
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}
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ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW);
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err_unlock:
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mutex_unlock(&chan->indio_dev->info_exist_lock);
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return ret;
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}
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EXPORT_SYMBOL_GPL(iio_read_channel_raw);
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static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan,
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int raw, int *processed, unsigned int scale)
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{
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int scale_type, scale_val, scale_val2, offset;
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s64 raw64 = raw;
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int ret;
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ret = iio_channel_read(chan, &offset, NULL, IIO_CHAN_INFO_SCALE);
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if (ret == 0)
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raw64 += offset;
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scale_type = iio_channel_read(chan, &scale_val, &scale_val2,
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IIO_CHAN_INFO_SCALE);
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if (scale_type < 0)
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return scale_type;
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switch (scale_type) {
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case IIO_VAL_INT:
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*processed = raw64 * scale_val;
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break;
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case IIO_VAL_INT_PLUS_MICRO:
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if (scale_val2 < 0)
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*processed = -raw64 * scale_val;
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else
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*processed = raw64 * scale_val;
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*processed += div_s64(raw64 * (s64)scale_val2 * scale,
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1000000LL);
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break;
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case IIO_VAL_INT_PLUS_NANO:
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if (scale_val2 < 0)
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*processed = -raw64 * scale_val;
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else
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*processed = raw64 * scale_val;
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*processed += div_s64(raw64 * (s64)scale_val2 * scale,
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1000000000LL);
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break;
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case IIO_VAL_FRACTIONAL:
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*processed = div_s64(raw64 * (s64)scale_val * scale,
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scale_val2);
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break;
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case IIO_VAL_FRACTIONAL_LOG2:
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*processed = (raw64 * (s64)scale_val * scale) >> scale_val2;
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break;
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default:
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return -EINVAL;
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}
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return 0;
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}
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int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,
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int *processed, unsigned int scale)
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{
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int ret;
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mutex_lock(&chan->indio_dev->info_exist_lock);
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if (chan->indio_dev->info == NULL) {
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ret = -ENODEV;
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goto err_unlock;
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}
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ret = iio_convert_raw_to_processed_unlocked(chan, raw, processed,
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scale);
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err_unlock:
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mutex_unlock(&chan->indio_dev->info_exist_lock);
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return ret;
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}
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EXPORT_SYMBOL_GPL(iio_convert_raw_to_processed);
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int iio_read_channel_processed(struct iio_channel *chan, int *val)
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{
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int ret;
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mutex_lock(&chan->indio_dev->info_exist_lock);
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if (chan->indio_dev->info == NULL) {
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ret = -ENODEV;
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goto err_unlock;
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}
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if (iio_channel_has_info(chan->channel, IIO_CHAN_INFO_PROCESSED)) {
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ret = iio_channel_read(chan, val, NULL,
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IIO_CHAN_INFO_PROCESSED);
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} else {
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ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW);
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if (ret < 0)
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goto err_unlock;
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ret = iio_convert_raw_to_processed_unlocked(chan, *val, val, 1);
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}
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err_unlock:
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mutex_unlock(&chan->indio_dev->info_exist_lock);
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return ret;
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}
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EXPORT_SYMBOL_GPL(iio_read_channel_processed);
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int iio_read_channel_scale(struct iio_channel *chan, int *val, int *val2)
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{
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int ret;
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mutex_lock(&chan->indio_dev->info_exist_lock);
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if (chan->indio_dev->info == NULL) {
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ret = -ENODEV;
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goto err_unlock;
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}
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ret = iio_channel_read(chan, val, val2, IIO_CHAN_INFO_SCALE);
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err_unlock:
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mutex_unlock(&chan->indio_dev->info_exist_lock);
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return ret;
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}
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EXPORT_SYMBOL_GPL(iio_read_channel_scale);
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int iio_get_channel_type(struct iio_channel *chan, enum iio_chan_type *type)
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{
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int ret = 0;
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/* Need to verify underlying driver has not gone away */
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mutex_lock(&chan->indio_dev->info_exist_lock);
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if (chan->indio_dev->info == NULL) {
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ret = -ENODEV;
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goto err_unlock;
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}
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*type = chan->channel->type;
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err_unlock:
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mutex_unlock(&chan->indio_dev->info_exist_lock);
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return ret;
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}
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EXPORT_SYMBOL_GPL(iio_get_channel_type);
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