--- /dev/null
+/* 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/of.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);
+
+
+/*
+ * Remove all map entries associated with the given iio device
+ */
+int iio_map_array_unregister(struct iio_dev *indio_dev)
+{
+ int ret = -ENODEV;
+ struct iio_map_internal *mapi;
+ struct list_head *pos, *tmp;
+
+ mutex_lock(&iio_map_list_lock);
+ list_for_each_safe(pos, tmp, &iio_map_list) {
+ mapi = list_entry(pos, struct iio_map_internal, l);
+ if (indio_dev == mapi->indio_dev) {
+ list_del(&mapi->l);
+ kfree(mapi);
+ ret = 0;
+ }
+ }
+ 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;
+}
+
+#ifdef CONFIG_OF
+
+static int iio_dev_node_match(struct device *dev, void *data)
+{
+ return dev->of_node == data && dev->type == &iio_device_type;
+}
+
+/**
+ * __of_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 __of_iio_simple_xlate(struct iio_dev *indio_dev,
+ const struct of_phandle_args *iiospec)
+{
+ if (!iiospec->args_count)
+ return 0;
+
+ if (iiospec->args[0] >= indio_dev->num_channels) {
+ dev_err(&indio_dev->dev, "invalid channel index %u\n",
+ iiospec->args[0]);
+ return -EINVAL;
+ }
+
+ return iiospec->args[0];
+}
+
+static int __of_iio_channel_get(struct iio_channel *channel,
+ struct device_node *np, int index)
+{
+ struct device *idev;
+ struct iio_dev *indio_dev;
+ int err;
+ struct of_phandle_args iiospec;
+
+ err = of_parse_phandle_with_args(np, "io-channels",
+ "#io-channel-cells",
+ index, &iiospec);
+ if (err)
+ return err;
+
+ idev = bus_find_device(&iio_bus_type, NULL, iiospec.np,
+ iio_dev_node_match);
+ of_node_put(iiospec.np);
+ if (idev == NULL)
+ return -EPROBE_DEFER;
+
+ indio_dev = dev_to_iio_dev(idev);
+ channel->indio_dev = indio_dev;
+ if (indio_dev->info->of_xlate)
+ index = indio_dev->info->of_xlate(indio_dev, &iiospec);
+ else
+ index = __of_iio_simple_xlate(indio_dev, &iiospec);
+ 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 *of_iio_channel_get(struct device_node *np, int index)
+{
+ struct iio_channel *channel;
+ int err;
+
+ if (index < 0)
+ return ERR_PTR(-EINVAL);
+
+ channel = kzalloc(sizeof(*channel), GFP_KERNEL);
+ if (channel == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ err = __of_iio_channel_get(channel, np, index);
+ if (err)
+ goto err_free_channel;
+
+ return channel;
+
+err_free_channel:
+ kfree(channel);
+ return ERR_PTR(err);
+}
+
+static struct iio_channel *of_iio_channel_get_by_name(struct device_node *np,
+ const char *name)
+{
+ struct iio_channel *chan = NULL;
+
+ /* Walk up the tree of devices looking for a matching iio channel */
+ while (np) {
+ 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 of_iio_channel_get()
+ * will fail.
+ */
+ if (name)
+ index = of_property_match_string(np, "io-channel-names",
+ name);
+ chan = of_iio_channel_get(np, index);
+ if (!IS_ERR(chan) || PTR_ERR(chan) == -EPROBE_DEFER)
+ break;
+ else if (name && index >= 0) {
+ pr_err("ERROR: could not get IIO channel %s:%s(%i)\n",
+ np->full_name, name ? name : "", index);
+ return NULL;
+ }
+
+ /*
+ * 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.
+ */
+ np = np->parent;
+ if (np && !of_get_property(np, "io-channel-ranges", NULL))
+ return NULL;
+ }
+
+ return chan;
+}
+
+static struct iio_channel *of_iio_channel_get_all(struct device *dev)
+{
+ struct iio_channel *chans;
+ int i, mapind, nummaps = 0;
+ int ret;
+
+ do {
+ ret = of_parse_phandle_with_args(dev->of_node,
+ "io-channels",
+ "#io-channel-cells",
+ nummaps, NULL);
+ if (ret < 0)
+ break;
+ } while (++nummaps);
+
+ if (nummaps == 0) /* no error, return NULL to search map table */
+ return NULL;
+
+ /* NULL terminated array to save passing size */
+ chans = kcalloc(nummaps + 1, sizeof(*chans), GFP_KERNEL);
+ if (chans == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ /* Search for OF matches */
+ for (mapind = 0; mapind < nummaps; mapind++) {
+ ret = __of_iio_channel_get(&chans[mapind], dev->of_node,
+ 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);
+}
+
+#else /* CONFIG_OF */
+
+static inline struct iio_channel *
+of_iio_channel_get_by_name(struct device_node *np, const char *name)
+{
+ return NULL;
+}
+
+static inline struct iio_channel *of_iio_channel_get_all(struct device *dev)
+{
+ return NULL;
+}
+
+#endif /* CONFIG_OF */
+
+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 == 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);
+}
+
+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 = of_iio_channel_get_by_name(dev->of_node,
+ channel_name);
+ if (channel != NULL)
+ return channel;
+ }
+
+ return iio_channel_get_sys(name, channel_name);
+}
+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(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 == NULL)
+ return ERR_PTR(-EINVAL);
+
+ chans = of_iio_channel_get_all(dev);
+ if (chans)
+ 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 = 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;
+ int vals[INDIO_MAX_RAW_ELEMENTS];
+ int ret;
+ int val_len = 2;
+
+ if (val2 == NULL)
+ 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)
+{
+ 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);
+
+int iio_read_channel_average_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_AVERAGE_RAW);
+err_unlock:
+ mutex_unlock(&chan->indio_dev->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, offset;
+ s64 raw64 = raw;
+ int ret;
+
+ ret = iio_channel_read(chan, &offset, NULL, IIO_CHAN_INFO_OFFSET);
+ 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);
+
+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_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_write(chan, val, 0, IIO_CHAN_INFO_RAW);
+err_unlock:
+ mutex_unlock(&chan->indio_dev->info_exist_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iio_write_channel_raw);
Code Review / kvmfornfv.git / blobdiff