[deliverable/linux.git] / drivers / iio / inkern.c

/* The industrial I/O core in kernel channel mapping
 *
 * Copyright (c) 2011 Jonathan Cameron
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */
#include <linux/err.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/mutex.h>

#include <linux/iio/iio.h>
#include "iio_core.h"
#include <linux/iio/machine.h>
#include <linux/iio/driver.h>
#include <linux/iio/consumer.h>

struct iio_map_internal {
	struct iio_dev *indio_dev;
	struct iio_map *map;
	struct list_head l;
};

static LIST_HEAD(iio_map_list);
static DEFINE_MUTEX(iio_map_list_lock);

int iio_map_array_register(struct iio_dev *indio_dev, struct iio_map *maps)
{
	int i = 0, ret = 0;
	struct iio_map_internal *mapi;

	if (maps == NULL)
		return 0;

	mutex_lock(&iio_map_list_lock);
	while (maps[i].consumer_dev_name != NULL) {
		mapi = kzalloc(sizeof(*mapi), GFP_KERNEL);
		if (mapi == NULL) {
			ret = -ENOMEM;
			goto error_ret;
		}
		mapi->map = &maps[i];
		mapi->indio_dev = indio_dev;
		list_add(&mapi->l, &iio_map_list);
		i++;
	}
error_ret:
	mutex_unlock(&iio_map_list_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(iio_map_array_register);


/* Assumes the exact same array (e.g. memory locations)
 * used at unregistration as used at registration rather than
 * more complex checking of contents.
 */
int iio_map_array_unregister(struct iio_dev *indio_dev,
			     struct iio_map *maps)
{
	int i = 0, ret = 0;
	bool found_it;
	struct iio_map_internal *mapi;

	if (maps == NULL)
		return 0;

	mutex_lock(&iio_map_list_lock);
	while (maps[i].consumer_dev_name != NULL) {
		found_it = false;
		list_for_each_entry(mapi, &iio_map_list, l)
			if (&maps[i] == mapi->map) {
				list_del(&mapi->l);
				kfree(mapi);
				found_it = true;
				break;
			}
		if (!found_it) {
			ret = -ENODEV;
			goto error_ret;
		}
		i++;
	}
error_ret:
	mutex_unlock(&iio_map_list_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(iio_map_array_unregister);

static const struct iio_chan_spec
*iio_chan_spec_from_name(const struct iio_dev *indio_dev, const char *name)
{
	int i;
	const struct iio_chan_spec *chan = NULL;

	for (i = 0; i < indio_dev->num_channels; i++)
		if (indio_dev->channels[i].datasheet_name &&
		    strcmp(name, indio_dev->channels[i].datasheet_name) == 0) {
			chan = &indio_dev->channels[i];
			break;
		}
	return chan;
}


struct iio_channel *iio_channel_get(const char *name, const char *channel_name)
{
	struct iio_map_internal *c_i = NULL, *c = NULL;
	struct iio_channel *channel;
	int err;

	if (name == NULL && channel_name == NULL)
		return ERR_PTR(-ENODEV);

	/* first find matching entry the channel map */
	mutex_lock(&iio_map_list_lock);
	list_for_each_entry(c_i, &iio_map_list, l) {
		if ((name && strcmp(name, c_i->map->consumer_dev_name) != 0) ||
		    (channel_name &&
		     strcmp(channel_name, c_i->map->consumer_channel) != 0))
			continue;
		c = c_i;
		iio_device_get(c->indio_dev);
		break;
	}
	mutex_unlock(&iio_map_list_lock);
	if (c == NULL)
		return ERR_PTR(-ENODEV);

	channel = kzalloc(sizeof(*channel), GFP_KERNEL);
	if (channel == NULL) {
		err = -ENOMEM;
		goto error_no_mem;
	}

	channel->indio_dev = c->indio_dev;

	if (c->map->adc_channel_label) {
		channel->channel =
			iio_chan_spec_from_name(channel->indio_dev,
						c->map->adc_channel_label);

		if (channel->channel == NULL) {
			err = -EINVAL;
			goto error_no_chan;
		}
	}

	return channel;

error_no_chan:
	kfree(channel);
error_no_mem:
	iio_device_put(c->indio_dev);
	return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(iio_channel_get);

void iio_channel_release(struct iio_channel *channel)
{
	iio_device_put(channel->indio_dev);
	kfree(channel);
}
EXPORT_SYMBOL_GPL(iio_channel_release);

struct iio_channel *iio_channel_get_all(const char *name)
{
	struct iio_channel *chans;
	struct iio_map_internal *c = NULL;
	int nummaps = 0;
	int mapind = 0;
	int i, ret;

	if (name == NULL)
		return ERR_PTR(-EINVAL);

	mutex_lock(&iio_map_list_lock);
	/* first count the matching maps */
	list_for_each_entry(c, &iio_map_list, l)
		if (name && strcmp(name, c->map->consumer_dev_name) != 0)
			continue;
		else
			nummaps++;

	if (nummaps == 0) {
		ret = -ENODEV;
		goto error_ret;
	}

	/* NULL terminated array to save passing size */
	chans = kzalloc(sizeof(*chans)*(nummaps + 1), GFP_KERNEL);
	if (chans == NULL) {
		ret = -ENOMEM;
		goto error_ret;
	}

	/* for each map fill in the chans element */
	list_for_each_entry(c, &iio_map_list, l) {
		if (name && strcmp(name, c->map->consumer_dev_name) != 0)
			continue;
		chans[mapind].indio_dev = c->indio_dev;
		chans[mapind].data = c->map->consumer_data;
		chans[mapind].channel =
			iio_chan_spec_from_name(chans[mapind].indio_dev,
						c->map->adc_channel_label);
		if (chans[mapind].channel == NULL) {
			ret = -EINVAL;
			goto error_free_chans;
		}
		iio_device_get(chans[mapind].indio_dev);
		mapind++;
	}
	if (mapind == 0) {
		ret = -ENODEV;
		goto error_free_chans;
	}
	mutex_unlock(&iio_map_list_lock);

	return chans;

error_free_chans:
	for (i = 0; i < nummaps; i++)
		iio_device_put(chans[i].indio_dev);
	kfree(chans);
error_ret:
	mutex_unlock(&iio_map_list_lock);

	return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(iio_channel_get_all);

void iio_channel_release_all(struct iio_channel *channels)
{
	struct iio_channel *chan = &channels[0];

	while (chan->indio_dev) {
		iio_device_put(chan->indio_dev);
		chan++;
	}
	kfree(channels);
}
EXPORT_SYMBOL_GPL(iio_channel_release_all);

static int iio_channel_read(struct iio_channel *chan, int *val, int *val2,
	enum iio_chan_info_enum info)
{
	int unused;

	if (val2 == NULL)
		val2 = &unused;

	return chan->indio_dev->info->read_raw(chan->indio_dev, chan->channel,
						val, val2, info);
}

int iio_read_channel_raw(struct iio_channel *chan, int *val)
{
	int ret;

	mutex_lock(&chan->indio_dev->info_exist_lock);
	if (chan->indio_dev->info == NULL) {
		ret = -ENODEV;
		goto err_unlock;
	}

	ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW);
err_unlock:
	mutex_unlock(&chan->indio_dev->info_exist_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(iio_read_channel_raw);

static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan,
	int raw, int *processed, unsigned int scale)
{
	int scale_type, scale_val, scale_val2, offset;
	s64 raw64 = raw;
	int ret;

	ret = iio_channel_read(chan, &offset, NULL, IIO_CHAN_INFO_SCALE);
	if (ret == 0)
		raw64 += offset;

	scale_type = iio_channel_read(chan, &scale_val, &scale_val2,
					IIO_CHAN_INFO_SCALE);
	if (scale_type < 0)
		return scale_type;

	switch (scale_type) {
	case IIO_VAL_INT:
		*processed = raw64 * scale_val;
		break;
	case IIO_VAL_INT_PLUS_MICRO:
		if (scale_val2 < 0)
			*processed = -raw64 * scale_val;
		else
			*processed = raw64 * scale_val;
		*processed += div_s64(raw64 * (s64)scale_val2 * scale,
				      1000000LL);
		break;
	case IIO_VAL_INT_PLUS_NANO:
		if (scale_val2 < 0)
			*processed = -raw64 * scale_val;
		else
			*processed = raw64 * scale_val;
		*processed += div_s64(raw64 * (s64)scale_val2 * scale,
				      1000000000LL);
		break;
	case IIO_VAL_FRACTIONAL:
		*processed = div_s64(raw64 * (s64)scale_val * scale,
				     scale_val2);
		break;
	case IIO_VAL_FRACTIONAL_LOG2:
		*processed = (raw64 * (s64)scale_val * scale) >> scale_val2;
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,
	int *processed, unsigned int scale)
{
	int ret;

	mutex_lock(&chan->indio_dev->info_exist_lock);
	if (chan->indio_dev->info == NULL) {
		ret = -ENODEV;
		goto err_unlock;
	}

	ret = iio_convert_raw_to_processed_unlocked(chan, raw, processed,
							scale);
err_unlock:
	mutex_unlock(&chan->indio_dev->info_exist_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(iio_convert_raw_to_processed);

int iio_read_channel_processed(struct iio_channel *chan, int *val)
{
	int ret;

	mutex_lock(&chan->indio_dev->info_exist_lock);
	if (chan->indio_dev->info == NULL) {
		ret = -ENODEV;
		goto err_unlock;
	}

	if (iio_channel_has_info(chan->channel, IIO_CHAN_INFO_PROCESSED)) {
		ret = iio_channel_read(chan, val, NULL,
				       IIO_CHAN_INFO_PROCESSED);
	} else {
		ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW);
		if (ret < 0)
			goto err_unlock;
		ret = iio_convert_raw_to_processed_unlocked(chan, *val, val, 1);
	}

err_unlock:
	mutex_unlock(&chan->indio_dev->info_exist_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(iio_read_channel_processed);

int iio_read_channel_scale(struct iio_channel *chan, int *val, int *val2)
{
	int ret;

	mutex_lock(&chan->indio_dev->info_exist_lock);
	if (chan->indio_dev->info == NULL) {
		ret = -ENODEV;
		goto err_unlock;
	}

	ret = iio_channel_read(chan, val, val2, IIO_CHAN_INFO_SCALE);
err_unlock:
	mutex_unlock(&chan->indio_dev->info_exist_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(iio_read_channel_scale);

int iio_get_channel_type(struct iio_channel *chan, enum iio_chan_type *type)
{
	int ret = 0;
	/* Need to verify underlying driver has not gone away */

	mutex_lock(&chan->indio_dev->info_exist_lock);
	if (chan->indio_dev->info == NULL) {
		ret = -ENODEV;
		goto err_unlock;
	}

	*type = chan->channel->type;
err_unlock:
	mutex_unlock(&chan->indio_dev->info_exist_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(iio_get_channel_type);
Commit	Line	Data
e27d75d7 JC	1	/* The industrial I/O core in kernel channel mapping
	2	*
	3	* Copyright (c) 2011 Jonathan Cameron
	4	*
	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.
	8	*/
	9	#include <linux/err.h>
	10	#include <linux/export.h>
	11	#include <linux/slab.h>
	12	#include <linux/mutex.h>
	13
06458e27	14	#include <linux/iio/iio.h>
e27d75d7	15	#include "iio_core.h"
06458e27 JC	16	#include <linux/iio/machine.h>
	17	#include <linux/iio/driver.h>
	18	#include <linux/iio/consumer.h>
e27d75d7 JC	19
	20	struct iio_map_internal {
	21	struct iio_dev *indio_dev;
	22	struct iio_map *map;
	23	struct list_head l;
	24	};
	25
	26	static LIST_HEAD(iio_map_list);
	27	static DEFINE_MUTEX(iio_map_list_lock);
	28
	29	int iio_map_array_register(struct iio_dev indio_dev, struct iio_map maps)
	30	{
	31	int i = 0, ret = 0;
	32	struct iio_map_internal *mapi;
	33
	34	if (maps == NULL)
	35	return 0;
	36
	37	mutex_lock(&iio_map_list_lock);
	38	while (maps[i].consumer_dev_name != NULL) {
	39	mapi = kzalloc(sizeof(*mapi), GFP_KERNEL);
	40	if (mapi == NULL) {
	41	ret = -ENOMEM;
	42	goto error_ret;
	43	}
	44	mapi->map = &maps[i];
	45	mapi->indio_dev = indio_dev;
	46	list_add(&mapi->l, &iio_map_list);
	47	i++;
	48	}
	49	error_ret:
	50	mutex_unlock(&iio_map_list_lock);
	51
	52	return ret;
	53	}
	54	EXPORT_SYMBOL_GPL(iio_map_array_register);
	55
	56
	57	/* Assumes the exact same array (e.g. memory locations)
	58	* used at unregistration as used at registration rather than
	59	* more complex checking of contents.
	60	*/
	61	int iio_map_array_unregister(struct iio_dev *indio_dev,
	62	struct iio_map *maps)
	63	{
	64	int i = 0, ret = 0;
	65	bool found_it;
	66	struct iio_map_internal *mapi;
	67
	68	if (maps == NULL)
	69	return 0;
	70
	71	mutex_lock(&iio_map_list_lock);
	72	while (maps[i].consumer_dev_name != NULL) {
	73	found_it = false;
	74	list_for_each_entry(mapi, &iio_map_list, l)
	75	if (&maps[i] == mapi->map) {
	76	list_del(&mapi->l);
	77	kfree(mapi);
	78	found_it = true;
	79	break;
	80	}
7737fa6d	81	if (!found_it) {
e27d75d7 JC	82	ret = -ENODEV;
	83	goto error_ret;
	84	}
218f4d43	85	i++;
e27d75d7 JC	86	}
	87	error_ret:
	88	mutex_unlock(&iio_map_list_lock);
	89
	90	return ret;
	91	}
	92	EXPORT_SYMBOL_GPL(iio_map_array_unregister);
	93
	94	static const struct iio_chan_spec
314be14b	95	iio_chan_spec_from_name(const struct iio_dev indio_dev, const char *name)
e27d75d7 JC	96	{
	97	int i;
	98	const struct iio_chan_spec *chan = NULL;
	99
	100	for (i = 0; i < indio_dev->num_channels; i++)
	101	if (indio_dev->channels[i].datasheet_name &&
	102	strcmp(name, indio_dev->channels[i].datasheet_name) == 0) {
	103	chan = &indio_dev->channels[i];
	104	break;
	105	}
	106	return chan;
	107	}
	108
	109
314be14b	110	struct iio_channel iio_channel_get(const char name, const char *channel_name)
e27d75d7 JC	111	{
	112	struct iio_map_internal c_i = NULL, c = NULL;
	113	struct iio_channel *channel;
3183bac1	114	int err;
e27d75d7 JC	115
	116	if (name == NULL && channel_name == NULL)
	117	return ERR_PTR(-ENODEV);
	118
	119	/* first find matching entry the channel map */
	120	mutex_lock(&iio_map_list_lock);
	121	list_for_each_entry(c_i, &iio_map_list, l) {
	122	if ((name && strcmp(name, c_i->map->consumer_dev_name) != 0) \|\|
	123	(channel_name &&
	124	strcmp(channel_name, c_i->map->consumer_channel) != 0))
	125	continue;
	126	c = c_i;
1875ffd2	127	iio_device_get(c->indio_dev);
e27d75d7 JC	128	break;
	129	}
	130	mutex_unlock(&iio_map_list_lock);
	131	if (c == NULL)
	132	return ERR_PTR(-ENODEV);
	133
2cc412b5	134	channel = kzalloc(sizeof(*channel), GFP_KERNEL);
3183bac1 KM	135	if (channel == NULL) {
3183bac1 KM	136	err = -ENOMEM;
801c4b5c	137	goto error_no_mem;
3183bac1	138	}
e27d75d7 JC	139
	140	channel->indio_dev = c->indio_dev;
	141
b2b79ffa	142	if (c->map->adc_channel_label) {
e27d75d7 JC	143	channel->channel =
	144	iio_chan_spec_from_name(channel->indio_dev,
	145	c->map->adc_channel_label);
	146
3183bac1 KM	147	if (channel->channel == NULL) {
3183bac1 KM	148	err = -EINVAL;
b2b79ffa	149	goto error_no_chan;
3183bac1	150	}
b2b79ffa KM	151	}
b2b79ffa KM	152
e27d75d7	153	return channel;
b2b79ffa KM	154
b2b79ffa KM	155	error_no_chan:
b2b79ffa	156	kfree(channel);
801c4b5c KM	157	error_no_mem:
801c4b5c KM	158	iio_device_put(c->indio_dev);
3183bac1	159	return ERR_PTR(err);
e27d75d7	160	}
314be14b	161	EXPORT_SYMBOL_GPL(iio_channel_get);
e27d75d7	162
314be14b	163	void iio_channel_release(struct iio_channel *channel)
e27d75d7	164	{
1875ffd2	165	iio_device_put(channel->indio_dev);
e27d75d7 JC	166	kfree(channel);
e27d75d7 JC	167	}
314be14b	168	EXPORT_SYMBOL_GPL(iio_channel_release);
e27d75d7	169
314be14b	170	struct iio_channel iio_channel_get_all(const char name)
e27d75d7 JC	171	{
	172	struct iio_channel *chans;
	173	struct iio_map_internal *c = NULL;
	174	int nummaps = 0;
	175	int mapind = 0;
	176	int i, ret;
	177
	178	if (name == NULL)
	179	return ERR_PTR(-EINVAL);
	180
	181	mutex_lock(&iio_map_list_lock);
	182	/* first count the matching maps */
	183	list_for_each_entry(c, &iio_map_list, l)
	184	if (name && strcmp(name, c->map->consumer_dev_name) != 0)
	185	continue;
	186	else
	187	nummaps++;
	188
	189	if (nummaps == 0) {
	190	ret = -ENODEV;
	191	goto error_ret;
	192	}
	193
	194	/* NULL terminated array to save passing size */
	195	chans = kzalloc(sizeof(chans)(nummaps + 1), GFP_KERNEL);
	196	if (chans == NULL) {
	197	ret = -ENOMEM;
	198	goto error_ret;
	199	}
	200
	201	/* for each map fill in the chans element */
	202	list_for_each_entry(c, &iio_map_list, l) {
	203	if (name && strcmp(name, c->map->consumer_dev_name) != 0)
	204	continue;
	205	chans[mapind].indio_dev = c->indio_dev;
0464415d	206	chans[mapind].data = c->map->consumer_data;
e27d75d7 JC	207	chans[mapind].channel =
	208	iio_chan_spec_from_name(chans[mapind].indio_dev,
	209	c->map->adc_channel_label);
	210	if (chans[mapind].channel == NULL) {
	211	ret = -EINVAL;
e27d75d7 JC	212	goto error_free_chans;
e27d75d7 JC	213	}
1875ffd2	214	iio_device_get(chans[mapind].indio_dev);
e27d75d7 JC	215	mapind++;
e27d75d7 JC	216	}
e27d75d7 JC	217	if (mapind == 0) {
	218	ret = -ENODEV;
	219	goto error_free_chans;
	220	}
e59b9afe DC	221	mutex_unlock(&iio_map_list_lock);
e59b9afe DC	222
e27d75d7 JC	223	return chans;
	224
	225	error_free_chans:
	226	for (i = 0; i < nummaps; i++)
1875ffd2	227	iio_device_put(chans[i].indio_dev);
e27d75d7 JC	228	kfree(chans);
	229	error_ret:
	230	mutex_unlock(&iio_map_list_lock);
	231
	232	return ERR_PTR(ret);
	233	}
314be14b	234	EXPORT_SYMBOL_GPL(iio_channel_get_all);
e27d75d7	235
314be14b	236	void iio_channel_release_all(struct iio_channel *channels)
e27d75d7 JC	237	{
	238	struct iio_channel *chan = &channels[0];
	239
	240	while (chan->indio_dev) {
1875ffd2	241	iio_device_put(chan->indio_dev);
e27d75d7 JC	242	chan++;
	243	}
	244	kfree(channels);
	245	}
314be14b	246	EXPORT_SYMBOL_GPL(iio_channel_release_all);
e27d75d7	247
48e44ce0 LPC	248	static int iio_channel_read(struct iio_channel chan, int val, int *val2,
	249	enum iio_chan_info_enum info)
	250	{
	251	int unused;
	252
	253	if (val2 == NULL)
	254	val2 = &unused;
	255
	256	return chan->indio_dev->info->read_raw(chan->indio_dev, chan->channel,
	257	val, val2, info);
	258	}
	259
314be14b	260	int iio_read_channel_raw(struct iio_channel chan, int val)
e27d75d7	261	{
48e44ce0	262	int ret;
e27d75d7 JC	263
	264	mutex_lock(&chan->indio_dev->info_exist_lock);
	265	if (chan->indio_dev->info == NULL) {
	266	ret = -ENODEV;
	267	goto err_unlock;
	268	}
	269
48e44ce0	270	ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW);
e27d75d7 JC	271	err_unlock:
	272	mutex_unlock(&chan->indio_dev->info_exist_lock);
	273
	274	return ret;
	275	}
314be14b	276	EXPORT_SYMBOL_GPL(iio_read_channel_raw);
e27d75d7	277
48e44ce0 LPC	278	static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan,
	279	int raw, int *processed, unsigned int scale)
	280	{
	281	int scale_type, scale_val, scale_val2, offset;
	282	s64 raw64 = raw;
	283	int ret;
	284
	285	ret = iio_channel_read(chan, &offset, NULL, IIO_CHAN_INFO_SCALE);
	286	if (ret == 0)
	287	raw64 += offset;
	288
	289	scale_type = iio_channel_read(chan, &scale_val, &scale_val2,
	290	IIO_CHAN_INFO_SCALE);
	291	if (scale_type < 0)
	292	return scale_type;
	293
	294	switch (scale_type) {
	295	case IIO_VAL_INT:
	296	processed = raw64 scale_val;
	297	break;
	298	case IIO_VAL_INT_PLUS_MICRO:
	299	if (scale_val2 < 0)
	300	processed = -raw64 scale_val;
	301	else
	302	processed = raw64 scale_val;
	303	processed += div_s64(raw64 (s64)scale_val2 * scale,
	304	1000000LL);
	305	break;
	306	case IIO_VAL_INT_PLUS_NANO:
	307	if (scale_val2 < 0)
	308	processed = -raw64 scale_val;
	309	else
	310	processed = raw64 scale_val;
	311	processed += div_s64(raw64 (s64)scale_val2 * scale,
	312	1000000000LL);
	313	break;
	314	case IIO_VAL_FRACTIONAL:
	315	processed = div_s64(raw64 (s64)scale_val * scale,
	316	scale_val2);
	317	break;
103d9fb9 LPC	318	case IIO_VAL_FRACTIONAL_LOG2:
	319	processed = (raw64 (s64)scale_val * scale) >> scale_val2;
	320	break;
48e44ce0 LPC	321	default:
	322	return -EINVAL;
	323	}
	324
	325	return 0;
	326	}
	327
	328	int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,
	329	int *processed, unsigned int scale)
	330	{
	331	int ret;
	332
	333	mutex_lock(&chan->indio_dev->info_exist_lock);
	334	if (chan->indio_dev->info == NULL) {
	335	ret = -ENODEV;
	336	goto err_unlock;
	337	}
	338
	339	ret = iio_convert_raw_to_processed_unlocked(chan, raw, processed,
	340	scale);
	341	err_unlock:
	342	mutex_unlock(&chan->indio_dev->info_exist_lock);
	343
	344	return ret;
	345	}
	346	EXPORT_SYMBOL_GPL(iio_convert_raw_to_processed);
	347
	348	int iio_read_channel_processed(struct iio_channel chan, int val)
	349	{
	350	int ret;
	351
	352	mutex_lock(&chan->indio_dev->info_exist_lock);
	353	if (chan->indio_dev->info == NULL) {
	354	ret = -ENODEV;
	355	goto err_unlock;
	356	}
	357
	358	if (iio_channel_has_info(chan->channel, IIO_CHAN_INFO_PROCESSED)) {
	359	ret = iio_channel_read(chan, val, NULL,
	360	IIO_CHAN_INFO_PROCESSED);
	361	} else {
	362	ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW);
	363	if (ret < 0)
	364	goto err_unlock;
	365	ret = iio_convert_raw_to_processed_unlocked(chan, *val, val, 1);
	366	}
	367
	368	err_unlock:
	369	mutex_unlock(&chan->indio_dev->info_exist_lock);
	370
	371	return ret;
	372	}
	373	EXPORT_SYMBOL_GPL(iio_read_channel_processed);
	374
314be14b	375	int iio_read_channel_scale(struct iio_channel chan, int val, int *val2)
e27d75d7 JC	376	{
	377	int ret;
	378
	379	mutex_lock(&chan->indio_dev->info_exist_lock);
	380	if (chan->indio_dev->info == NULL) {
	381	ret = -ENODEV;
	382	goto err_unlock;
	383	}
	384
48e44ce0	385	ret = iio_channel_read(chan, val, val2, IIO_CHAN_INFO_SCALE);
e27d75d7 JC	386	err_unlock:
	387	mutex_unlock(&chan->indio_dev->info_exist_lock);
	388
	389	return ret;
	390	}
314be14b	391	EXPORT_SYMBOL_GPL(iio_read_channel_scale);
e27d75d7	392
314be14b	393	int iio_get_channel_type(struct iio_channel chan, enum iio_chan_type type)
e27d75d7 JC	394	{
	395	int ret = 0;
	396	/* Need to verify underlying driver has not gone away */
	397
	398	mutex_lock(&chan->indio_dev->info_exist_lock);
	399	if (chan->indio_dev->info == NULL) {
	400	ret = -ENODEV;
	401	goto err_unlock;
	402	}
	403
	404	*type = chan->channel->type;
	405	err_unlock:
	406	mutex_unlock(&chan->indio_dev->info_exist_lock);
	407
	408	return ret;
	409	}
314be14b	410	EXPORT_SYMBOL_GPL(iio_get_channel_type);