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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/iio/inkern.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/iio/inkern.c')
-rw-r--r--drivers/iio/inkern.c1085
1 files changed, 1085 insertions, 0 deletions
diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
new file mode 100644
index 0000000000..7a1f671331
--- /dev/null
+++ b/drivers/iio/inkern.c
@@ -0,0 +1,1085 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* The industrial I/O core in kernel channel mapping
+ *
+ * Copyright (c) 2011 Jonathan Cameron
+ */
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/minmax.h>
+#include <linux/mutex.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/iio-opaque.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);
+
+static int iio_map_array_unregister_locked(struct iio_dev *indio_dev)
+{
+ int ret = -ENODEV;
+ struct iio_map_internal *mapi, *next;
+
+ list_for_each_entry_safe(mapi, next, &iio_map_list, l) {
+ if (indio_dev == mapi->indio_dev) {
+ list_del(&mapi->l);
+ kfree(mapi);
+ ret = 0;
+ }
+ }
+ return ret;
+}
+
+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)
+ return 0;
+
+ mutex_lock(&iio_map_list_lock);
+ while (maps[i].consumer_dev_name) {
+ mapi = kzalloc(sizeof(*mapi), GFP_KERNEL);
+ if (!mapi) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+ mapi->map = &maps[i];
+ mapi->indio_dev = indio_dev;
+ list_add_tail(&mapi->l, &iio_map_list);
+ i++;
+ }
+error_ret:
+ if (ret)
+ iio_map_array_unregister_locked(indio_dev);
+ mutex_unlock(&iio_map_list_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_map_array_register);
+
+/*
+ * Remove all map entries associated with the given iio device
+ */
+int iio_map_array_unregister(struct iio_dev *indio_dev)
+{
+ int ret;
+
+ mutex_lock(&iio_map_list_lock);
+ ret = iio_map_array_unregister_locked(indio_dev);
+ mutex_unlock(&iio_map_list_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_map_array_unregister);
+
+static void iio_map_array_unregister_cb(void *indio_dev)
+{
+ iio_map_array_unregister(indio_dev);
+}
+
+int devm_iio_map_array_register(struct device *dev, struct iio_dev *indio_dev, struct iio_map *maps)
+{
+ int ret;
+
+ ret = iio_map_array_register(indio_dev, maps);
+ if (ret)
+ return ret;
+
+ return devm_add_action_or_reset(dev, iio_map_array_unregister_cb, indio_dev);
+}
+EXPORT_SYMBOL_GPL(devm_iio_map_array_register);
+
+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;
+}
+
+/**
+ * __fwnode_iio_simple_xlate - translate iiospec to the IIO channel index
+ * @indio_dev: pointer to the iio_dev structure
+ * @iiospec: IIO specifier as found in the device tree
+ *
+ * This is simple translation function, suitable for the most 1:1 mapped
+ * channels in IIO chips. This function performs only one sanity check:
+ * whether IIO index is less than num_channels (that is specified in the
+ * iio_dev).
+ */
+static int __fwnode_iio_simple_xlate(struct iio_dev *indio_dev,
+ const struct fwnode_reference_args *iiospec)
+{
+ if (!iiospec->nargs)
+ return 0;
+
+ if (iiospec->args[0] >= indio_dev->num_channels) {
+ dev_err(&indio_dev->dev, "invalid channel index %llu\n",
+ iiospec->args[0]);
+ return -EINVAL;
+ }
+
+ return iiospec->args[0];
+}
+
+static int __fwnode_iio_channel_get(struct iio_channel *channel,
+ struct fwnode_handle *fwnode, int index)
+{
+ struct fwnode_reference_args iiospec;
+ struct device *idev;
+ struct iio_dev *indio_dev;
+ int err;
+
+ err = fwnode_property_get_reference_args(fwnode, "io-channels",
+ "#io-channel-cells", 0,
+ index, &iiospec);
+ if (err)
+ return err;
+
+ idev = bus_find_device_by_fwnode(&iio_bus_type, iiospec.fwnode);
+ if (!idev) {
+ fwnode_handle_put(iiospec.fwnode);
+ return -EPROBE_DEFER;
+ }
+
+ indio_dev = dev_to_iio_dev(idev);
+ channel->indio_dev = indio_dev;
+ if (indio_dev->info->fwnode_xlate)
+ index = indio_dev->info->fwnode_xlate(indio_dev, &iiospec);
+ else
+ index = __fwnode_iio_simple_xlate(indio_dev, &iiospec);
+ fwnode_handle_put(iiospec.fwnode);
+ if (index < 0)
+ goto err_put;
+ channel->channel = &indio_dev->channels[index];
+
+ return 0;
+
+err_put:
+ iio_device_put(indio_dev);
+ return index;
+}
+
+static struct iio_channel *fwnode_iio_channel_get(struct fwnode_handle *fwnode,
+ int index)
+{
+ struct iio_channel *channel;
+ int err;
+
+ if (index < 0)
+ return ERR_PTR(-EINVAL);
+
+ channel = kzalloc(sizeof(*channel), GFP_KERNEL);
+ if (!channel)
+ return ERR_PTR(-ENOMEM);
+
+ err = __fwnode_iio_channel_get(channel, fwnode, index);
+ if (err)
+ goto err_free_channel;
+
+ return channel;
+
+err_free_channel:
+ kfree(channel);
+ return ERR_PTR(err);
+}
+
+static struct iio_channel *
+__fwnode_iio_channel_get_by_name(struct fwnode_handle *fwnode, const char *name)
+{
+ struct iio_channel *chan;
+ int index = 0;
+
+ /*
+ * For named iio channels, first look up the name in the
+ * "io-channel-names" property. If it cannot be found, the
+ * index will be an error code, and fwnode_iio_channel_get()
+ * will fail.
+ */
+ if (name)
+ index = fwnode_property_match_string(fwnode, "io-channel-names",
+ name);
+
+ chan = fwnode_iio_channel_get(fwnode, index);
+ if (!IS_ERR(chan) || PTR_ERR(chan) == -EPROBE_DEFER)
+ return chan;
+ if (name) {
+ if (index >= 0) {
+ pr_err("ERROR: could not get IIO channel %pfw:%s(%i)\n",
+ fwnode, name, index);
+ /*
+ * In this case, we found 'name' in 'io-channel-names'
+ * but somehow we still fail so that we should not proceed
+ * with any other lookup. Hence, explicitly return -EINVAL
+ * (maybe not the better error code) so that the caller
+ * won't do a system lookup.
+ */
+ return ERR_PTR(-EINVAL);
+ }
+ /*
+ * If index < 0, then fwnode_property_get_reference_args() fails
+ * with -EINVAL or -ENOENT (ACPI case) which is expected. We
+ * should not proceed if we get any other error.
+ */
+ if (PTR_ERR(chan) != -EINVAL && PTR_ERR(chan) != -ENOENT)
+ return chan;
+ } else if (PTR_ERR(chan) != -ENOENT) {
+ /*
+ * if !name, then we should only proceed the lookup if
+ * fwnode_property_get_reference_args() returns -ENOENT.
+ */
+ return chan;
+ }
+
+ /* so we continue the lookup */
+ return ERR_PTR(-ENODEV);
+}
+
+struct iio_channel *fwnode_iio_channel_get_by_name(struct fwnode_handle *fwnode,
+ const char *name)
+{
+ struct fwnode_handle *parent;
+ struct iio_channel *chan;
+
+ /* Walk up the tree of devices looking for a matching iio channel */
+ chan = __fwnode_iio_channel_get_by_name(fwnode, name);
+ if (!IS_ERR(chan) || PTR_ERR(chan) != -ENODEV)
+ return chan;
+
+ /*
+ * No matching IIO channel found on this node.
+ * If the parent node has a "io-channel-ranges" property,
+ * then we can try one of its channels.
+ */
+ fwnode_for_each_parent_node(fwnode, parent) {
+ if (!fwnode_property_present(parent, "io-channel-ranges")) {
+ fwnode_handle_put(parent);
+ return ERR_PTR(-ENODEV);
+ }
+
+ chan = __fwnode_iio_channel_get_by_name(fwnode, name);
+ if (!IS_ERR(chan) || PTR_ERR(chan) != -ENODEV) {
+ fwnode_handle_put(parent);
+ return chan;
+ }
+ }
+
+ return ERR_PTR(-ENODEV);
+}
+EXPORT_SYMBOL_GPL(fwnode_iio_channel_get_by_name);
+
+static struct iio_channel *fwnode_iio_channel_get_all(struct device *dev)
+{
+ struct fwnode_handle *fwnode = dev_fwnode(dev);
+ struct iio_channel *chans;
+ int i, mapind, nummaps = 0;
+ int ret;
+
+ do {
+ ret = fwnode_property_get_reference_args(fwnode, "io-channels",
+ "#io-channel-cells", 0,
+ nummaps, NULL);
+ if (ret < 0)
+ break;
+ } while (++nummaps);
+
+ if (nummaps == 0)
+ return ERR_PTR(-ENODEV);
+
+ /* NULL terminated array to save passing size */
+ chans = kcalloc(nummaps + 1, sizeof(*chans), GFP_KERNEL);
+ if (!chans)
+ return ERR_PTR(-ENOMEM);
+
+ /* Search for FW matches */
+ for (mapind = 0; mapind < nummaps; mapind++) {
+ ret = __fwnode_iio_channel_get(&chans[mapind], fwnode, mapind);
+ if (ret)
+ goto error_free_chans;
+ }
+ return chans;
+
+error_free_chans:
+ for (i = 0; i < mapind; i++)
+ iio_device_put(chans[i].indio_dev);
+ kfree(chans);
+ return ERR_PTR(ret);
+}
+
+static struct iio_channel *iio_channel_get_sys(const char *name,
+ const char *channel_name)
+{
+ struct iio_map_internal *c_i = NULL, *c = NULL;
+ struct iio_channel *channel;
+ int err;
+
+ if (!(name || channel_name))
+ 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)
+ return ERR_PTR(-ENODEV);
+
+ channel = kzalloc(sizeof(*channel), GFP_KERNEL);
+ if (!channel) {
+ 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) {
+ 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);
+}
+
+struct iio_channel *iio_channel_get(struct device *dev,
+ const char *channel_name)
+{
+ const char *name = dev ? dev_name(dev) : NULL;
+ struct iio_channel *channel;
+
+ if (dev) {
+ channel = fwnode_iio_channel_get_by_name(dev_fwnode(dev),
+ channel_name);
+ if (!IS_ERR(channel) || PTR_ERR(channel) != -ENODEV)
+ return channel;
+ }
+
+ return iio_channel_get_sys(name, channel_name);
+}
+EXPORT_SYMBOL_GPL(iio_channel_get);
+
+void iio_channel_release(struct iio_channel *channel)
+{
+ if (!channel)
+ return;
+ iio_device_put(channel->indio_dev);
+ kfree(channel);
+}
+EXPORT_SYMBOL_GPL(iio_channel_release);
+
+static void devm_iio_channel_free(void *iio_channel)
+{
+ iio_channel_release(iio_channel);
+}
+
+struct iio_channel *devm_iio_channel_get(struct device *dev,
+ const char *channel_name)
+{
+ struct iio_channel *channel;
+ int ret;
+
+ channel = iio_channel_get(dev, channel_name);
+ if (IS_ERR(channel))
+ return channel;
+
+ ret = devm_add_action_or_reset(dev, devm_iio_channel_free, channel);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return channel;
+}
+EXPORT_SYMBOL_GPL(devm_iio_channel_get);
+
+struct iio_channel *devm_fwnode_iio_channel_get_by_name(struct device *dev,
+ struct fwnode_handle *fwnode,
+ const char *channel_name)
+{
+ struct iio_channel *channel;
+ int ret;
+
+ channel = fwnode_iio_channel_get_by_name(fwnode, channel_name);
+ if (IS_ERR(channel))
+ return channel;
+
+ ret = devm_add_action_or_reset(dev, devm_iio_channel_free, channel);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return channel;
+}
+EXPORT_SYMBOL_GPL(devm_fwnode_iio_channel_get_by_name);
+
+struct iio_channel *iio_channel_get_all(struct device *dev)
+{
+ const char *name;
+ struct iio_channel *chans;
+ struct iio_map_internal *c = NULL;
+ int nummaps = 0;
+ int mapind = 0;
+ int i, ret;
+
+ if (!dev)
+ return ERR_PTR(-EINVAL);
+
+ chans = fwnode_iio_channel_get_all(dev);
+ /*
+ * We only want to carry on if the error is -ENODEV. Anything else
+ * should be reported up the stack.
+ */
+ if (!IS_ERR(chans) || PTR_ERR(chans) != -ENODEV)
+ return chans;
+
+ name = dev_name(dev);
+
+ 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 = kcalloc(nummaps + 1, sizeof(*chans), GFP_KERNEL);
+ if (!chans) {
+ 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) {
+ 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 void devm_iio_channel_free_all(void *iio_channels)
+{
+ iio_channel_release_all(iio_channels);
+}
+
+struct iio_channel *devm_iio_channel_get_all(struct device *dev)
+{
+ struct iio_channel *channels;
+ int ret;
+
+ channels = iio_channel_get_all(dev);
+ if (IS_ERR(channels))
+ return channels;
+
+ ret = devm_add_action_or_reset(dev, devm_iio_channel_free_all,
+ channels);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return channels;
+}
+EXPORT_SYMBOL_GPL(devm_iio_channel_get_all);
+
+static int iio_channel_read(struct iio_channel *chan, int *val, int *val2,
+ enum iio_chan_info_enum info)
+{
+ int unused;
+ int vals[INDIO_MAX_RAW_ELEMENTS];
+ int ret;
+ int val_len = 2;
+
+ if (!val2)
+ val2 = &unused;
+
+ if (!iio_channel_has_info(chan->channel, info))
+ return -EINVAL;
+
+ if (chan->indio_dev->info->read_raw_multi) {
+ ret = chan->indio_dev->info->read_raw_multi(chan->indio_dev,
+ chan->channel, INDIO_MAX_RAW_ELEMENTS,
+ vals, &val_len, info);
+ *val = vals[0];
+ *val2 = vals[1];
+ } else {
+ ret = chan->indio_dev->info->read_raw(chan->indio_dev,
+ chan->channel, val, val2, info);
+ }
+
+ return ret;
+}
+
+int iio_read_channel_raw(struct iio_channel *chan, int *val)
+{
+ struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
+ int ret;
+
+ mutex_lock(&iio_dev_opaque->info_exist_lock);
+ if (!chan->indio_dev->info) {
+ ret = -ENODEV;
+ goto err_unlock;
+ }
+
+ ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW);
+err_unlock:
+ mutex_unlock(&iio_dev_opaque->info_exist_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_read_channel_raw);
+
+int iio_read_channel_average_raw(struct iio_channel *chan, int *val)
+{
+ struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
+ int ret;
+
+ mutex_lock(&iio_dev_opaque->info_exist_lock);
+ if (!chan->indio_dev->info) {
+ ret = -ENODEV;
+ goto err_unlock;
+ }
+
+ ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_AVERAGE_RAW);
+err_unlock:
+ mutex_unlock(&iio_dev_opaque->info_exist_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_read_channel_average_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;
+ int offset_type, offset_val, offset_val2;
+ s64 raw64 = raw;
+
+ offset_type = iio_channel_read(chan, &offset_val, &offset_val2,
+ IIO_CHAN_INFO_OFFSET);
+ if (offset_type >= 0) {
+ switch (offset_type) {
+ case IIO_VAL_INT:
+ break;
+ case IIO_VAL_INT_PLUS_MICRO:
+ case IIO_VAL_INT_PLUS_NANO:
+ /*
+ * Both IIO_VAL_INT_PLUS_MICRO and IIO_VAL_INT_PLUS_NANO
+ * implicitely truncate the offset to it's integer form.
+ */
+ break;
+ case IIO_VAL_FRACTIONAL:
+ offset_val /= offset_val2;
+ break;
+ case IIO_VAL_FRACTIONAL_LOG2:
+ offset_val >>= offset_val2;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ raw64 += offset_val;
+ }
+
+ scale_type = iio_channel_read(chan, &scale_val, &scale_val2,
+ IIO_CHAN_INFO_SCALE);
+ if (scale_type < 0) {
+ /*
+ * If no channel scaling is available apply consumer scale to
+ * raw value and return.
+ */
+ *processed = raw * scale;
+ return 0;
+ }
+
+ switch (scale_type) {
+ case IIO_VAL_INT:
+ *processed = raw64 * scale_val * scale;
+ 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)
+{
+ struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
+ int ret;
+
+ mutex_lock(&iio_dev_opaque->info_exist_lock);
+ if (!chan->indio_dev->info) {
+ ret = -ENODEV;
+ goto err_unlock;
+ }
+
+ ret = iio_convert_raw_to_processed_unlocked(chan, raw, processed,
+ scale);
+err_unlock:
+ mutex_unlock(&iio_dev_opaque->info_exist_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_convert_raw_to_processed);
+
+int iio_read_channel_attribute(struct iio_channel *chan, int *val, int *val2,
+ enum iio_chan_info_enum attribute)
+{
+ struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
+ int ret;
+
+ mutex_lock(&iio_dev_opaque->info_exist_lock);
+ if (!chan->indio_dev->info) {
+ ret = -ENODEV;
+ goto err_unlock;
+ }
+
+ ret = iio_channel_read(chan, val, val2, attribute);
+err_unlock:
+ mutex_unlock(&iio_dev_opaque->info_exist_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_read_channel_attribute);
+
+int iio_read_channel_offset(struct iio_channel *chan, int *val, int *val2)
+{
+ return iio_read_channel_attribute(chan, val, val2, IIO_CHAN_INFO_OFFSET);
+}
+EXPORT_SYMBOL_GPL(iio_read_channel_offset);
+
+int iio_read_channel_processed_scale(struct iio_channel *chan, int *val,
+ unsigned int scale)
+{
+ struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
+ int ret;
+
+ mutex_lock(&iio_dev_opaque->info_exist_lock);
+ if (!chan->indio_dev->info) {
+ 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);
+ if (ret < 0)
+ goto err_unlock;
+ *val *= scale;
+ } 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,
+ scale);
+ }
+
+err_unlock:
+ mutex_unlock(&iio_dev_opaque->info_exist_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_read_channel_processed_scale);
+
+int iio_read_channel_processed(struct iio_channel *chan, int *val)
+{
+ /* This is just a special case with scale factor 1 */
+ return iio_read_channel_processed_scale(chan, val, 1);
+}
+EXPORT_SYMBOL_GPL(iio_read_channel_processed);
+
+int iio_read_channel_scale(struct iio_channel *chan, int *val, int *val2)
+{
+ return iio_read_channel_attribute(chan, val, val2, IIO_CHAN_INFO_SCALE);
+}
+EXPORT_SYMBOL_GPL(iio_read_channel_scale);
+
+static int iio_channel_read_avail(struct iio_channel *chan,
+ const int **vals, int *type, int *length,
+ enum iio_chan_info_enum info)
+{
+ if (!iio_channel_has_available(chan->channel, info))
+ return -EINVAL;
+
+ return chan->indio_dev->info->read_avail(chan->indio_dev, chan->channel,
+ vals, type, length, info);
+}
+
+int iio_read_avail_channel_attribute(struct iio_channel *chan,
+ const int **vals, int *type, int *length,
+ enum iio_chan_info_enum attribute)
+{
+ struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
+ int ret;
+
+ mutex_lock(&iio_dev_opaque->info_exist_lock);
+ if (!chan->indio_dev->info) {
+ ret = -ENODEV;
+ goto err_unlock;
+ }
+
+ ret = iio_channel_read_avail(chan, vals, type, length, attribute);
+err_unlock:
+ mutex_unlock(&iio_dev_opaque->info_exist_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_read_avail_channel_attribute);
+
+int iio_read_avail_channel_raw(struct iio_channel *chan,
+ const int **vals, int *length)
+{
+ int ret;
+ int type;
+
+ ret = iio_read_avail_channel_attribute(chan, vals, &type, length,
+ IIO_CHAN_INFO_RAW);
+
+ if (ret >= 0 && type != IIO_VAL_INT)
+ /* raw values are assumed to be IIO_VAL_INT */
+ ret = -EINVAL;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_read_avail_channel_raw);
+
+static int iio_channel_read_max(struct iio_channel *chan,
+ int *val, int *val2, int *type,
+ enum iio_chan_info_enum info)
+{
+ const int *vals;
+ int length;
+ int ret;
+
+ ret = iio_channel_read_avail(chan, &vals, type, &length, info);
+ if (ret < 0)
+ return ret;
+
+ switch (ret) {
+ case IIO_AVAIL_RANGE:
+ switch (*type) {
+ case IIO_VAL_INT:
+ *val = vals[2];
+ break;
+ default:
+ *val = vals[4];
+ if (val2)
+ *val2 = vals[5];
+ }
+ return 0;
+
+ case IIO_AVAIL_LIST:
+ if (length <= 0)
+ return -EINVAL;
+ switch (*type) {
+ case IIO_VAL_INT:
+ *val = max_array(vals, length);
+ break;
+ default:
+ /* TODO: learn about max for other iio values */
+ return -EINVAL;
+ }
+ return 0;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+int iio_read_max_channel_raw(struct iio_channel *chan, int *val)
+{
+ struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
+ int ret;
+ int type;
+
+ mutex_lock(&iio_dev_opaque->info_exist_lock);
+ if (!chan->indio_dev->info) {
+ ret = -ENODEV;
+ goto err_unlock;
+ }
+
+ ret = iio_channel_read_max(chan, val, NULL, &type, IIO_CHAN_INFO_RAW);
+err_unlock:
+ mutex_unlock(&iio_dev_opaque->info_exist_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_read_max_channel_raw);
+
+static int iio_channel_read_min(struct iio_channel *chan,
+ int *val, int *val2, int *type,
+ enum iio_chan_info_enum info)
+{
+ const int *vals;
+ int length;
+ int ret;
+
+ ret = iio_channel_read_avail(chan, &vals, type, &length, info);
+ if (ret < 0)
+ return ret;
+
+ switch (ret) {
+ case IIO_AVAIL_RANGE:
+ switch (*type) {
+ case IIO_VAL_INT:
+ *val = vals[0];
+ break;
+ default:
+ *val = vals[0];
+ if (val2)
+ *val2 = vals[1];
+ }
+ return 0;
+
+ case IIO_AVAIL_LIST:
+ if (length <= 0)
+ return -EINVAL;
+ switch (*type) {
+ case IIO_VAL_INT:
+ *val = min_array(vals, length);
+ break;
+ default:
+ /* TODO: learn about min for other iio values */
+ return -EINVAL;
+ }
+ return 0;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+int iio_read_min_channel_raw(struct iio_channel *chan, int *val)
+{
+ struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
+ int ret;
+ int type;
+
+ mutex_lock(&iio_dev_opaque->info_exist_lock);
+ if (!chan->indio_dev->info) {
+ ret = -ENODEV;
+ goto err_unlock;
+ }
+
+ ret = iio_channel_read_min(chan, val, NULL, &type, IIO_CHAN_INFO_RAW);
+err_unlock:
+ mutex_unlock(&iio_dev_opaque->info_exist_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_read_min_channel_raw);
+
+int iio_get_channel_type(struct iio_channel *chan, enum iio_chan_type *type)
+{
+ struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
+ int ret = 0;
+ /* Need to verify underlying driver has not gone away */
+
+ mutex_lock(&iio_dev_opaque->info_exist_lock);
+ if (!chan->indio_dev->info) {
+ ret = -ENODEV;
+ goto err_unlock;
+ }
+
+ *type = chan->channel->type;
+err_unlock:
+ mutex_unlock(&iio_dev_opaque->info_exist_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_get_channel_type);
+
+static int iio_channel_write(struct iio_channel *chan, int val, int val2,
+ enum iio_chan_info_enum info)
+{
+ return chan->indio_dev->info->write_raw(chan->indio_dev,
+ chan->channel, val, val2, info);
+}
+
+int iio_write_channel_attribute(struct iio_channel *chan, int val, int val2,
+ enum iio_chan_info_enum attribute)
+{
+ struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
+ int ret;
+
+ mutex_lock(&iio_dev_opaque->info_exist_lock);
+ if (!chan->indio_dev->info) {
+ ret = -ENODEV;
+ goto err_unlock;
+ }
+
+ ret = iio_channel_write(chan, val, val2, attribute);
+err_unlock:
+ mutex_unlock(&iio_dev_opaque->info_exist_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_write_channel_attribute);
+
+int iio_write_channel_raw(struct iio_channel *chan, int val)
+{
+ return iio_write_channel_attribute(chan, val, 0, IIO_CHAN_INFO_RAW);
+}
+EXPORT_SYMBOL_GPL(iio_write_channel_raw);
+
+unsigned int iio_get_channel_ext_info_count(struct iio_channel *chan)
+{
+ const struct iio_chan_spec_ext_info *ext_info;
+ unsigned int i = 0;
+
+ if (!chan->channel->ext_info)
+ return i;
+
+ for (ext_info = chan->channel->ext_info; ext_info->name; ext_info++)
+ ++i;
+
+ return i;
+}
+EXPORT_SYMBOL_GPL(iio_get_channel_ext_info_count);
+
+static const struct iio_chan_spec_ext_info *
+iio_lookup_ext_info(const struct iio_channel *chan, const char *attr)
+{
+ const struct iio_chan_spec_ext_info *ext_info;
+
+ if (!chan->channel->ext_info)
+ return NULL;
+
+ for (ext_info = chan->channel->ext_info; ext_info->name; ++ext_info) {
+ if (!strcmp(attr, ext_info->name))
+ return ext_info;
+ }
+
+ return NULL;
+}
+
+ssize_t iio_read_channel_ext_info(struct iio_channel *chan,
+ const char *attr, char *buf)
+{
+ const struct iio_chan_spec_ext_info *ext_info;
+
+ ext_info = iio_lookup_ext_info(chan, attr);
+ if (!ext_info)
+ return -EINVAL;
+
+ return ext_info->read(chan->indio_dev, ext_info->private,
+ chan->channel, buf);
+}
+EXPORT_SYMBOL_GPL(iio_read_channel_ext_info);
+
+ssize_t iio_write_channel_ext_info(struct iio_channel *chan, const char *attr,
+ const char *buf, size_t len)
+{
+ const struct iio_chan_spec_ext_info *ext_info;
+
+ ext_info = iio_lookup_ext_info(chan, attr);
+ if (!ext_info)
+ return -EINVAL;
+
+ return ext_info->write(chan->indio_dev, ext_info->private,
+ chan->channel, buf, len);
+}
+EXPORT_SYMBOL_GPL(iio_write_channel_ext_info);