IIO: Move the core files to drivers/iio

Take the core support + the kfifo buffer implentation out of
staging.  Whilst we are far from done in improving this subsystem
it is now at a stage where the userspae interfaces (provided by
the core) can be considered stable.

Drivers will follow over a longer time scale.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 292 insertions, 0 deletions

diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
new file mode 100644
index 000000000000..22ddf62b107c
--- /dev/null
+++ b/drivers/iio/inkern.c
@@ -0,0 +1,292 @@
+/* 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 == false) {
+                        ret = -ENODEV;
+                        goto error_ret;
+                }
+        }
+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_st_channel_get(const char *name,
+                                       const char *channel_name)
+{
+        struct iio_map_internal *c_i = NULL, *c = NULL;
+        struct iio_channel *channel;
+
+        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;
+                get_device(&c->indio_dev->dev);
+                break;
+        }
+        mutex_unlock(&iio_map_list_lock);
+        if (c == NULL)
+                return ERR_PTR(-ENODEV);
+
+        channel = kmalloc(sizeof(*channel), GFP_KERNEL);
+        if (channel == NULL)
+                return ERR_PTR(-ENOMEM);
+
+        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);
+
+        return channel;
+}
+EXPORT_SYMBOL_GPL(iio_st_channel_get);
+
+void iio_st_channel_release(struct iio_channel *channel)
+{
+        put_device(&channel->indio_dev->dev);
+        kfree(channel);
+}
+EXPORT_SYMBOL_GPL(iio_st_channel_release);
+
+struct iio_channel *iio_st_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].channel =
+                        iio_chan_spec_from_name(chans[mapind].indio_dev,
+                                                c->map->adc_channel_label);
+                if (chans[mapind].channel == NULL) {
+                        ret = -EINVAL;
+                        put_device(&chans[mapind].indio_dev->dev);
+                        goto error_free_chans;
+                }
+                get_device(&chans[mapind].indio_dev->dev);
+                mapind++;
+        }
+        mutex_unlock(&iio_map_list_lock);
+        if (mapind == 0) {
+                ret = -ENODEV;
+                goto error_free_chans;
+        }
+        return chans;
+
+error_free_chans:
+        for (i = 0; i < nummaps; i++)
+                if (chans[i].indio_dev)
+                        put_device(&chans[i].indio_dev->dev);
+        kfree(chans);
+error_ret:
+        mutex_unlock(&iio_map_list_lock);
+
+        return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(iio_st_channel_get_all);
+
+void iio_st_channel_release_all(struct iio_channel *channels)
+{
+        struct iio_channel *chan = &channels[0];
+
+        while (chan->indio_dev) {
+                put_device(&chan->indio_dev->dev);
+                chan++;
+        }
+        kfree(channels);
+}
+EXPORT_SYMBOL_GPL(iio_st_channel_release_all);
+
+int iio_st_read_channel_raw(struct iio_channel *chan, int *val)
+{
+        int val2, ret;
+
+        mutex_lock(&chan->indio_dev->info_exist_lock);
+        if (chan->indio_dev->info == NULL) {
+                ret = -ENODEV;
+                goto err_unlock;
+        }
+
+        ret = chan->indio_dev->info->read_raw(chan->indio_dev, chan->channel,
+                                              val, &val2, 0);
+err_unlock:
+        mutex_unlock(&chan->indio_dev->info_exist_lock);
+
+        return ret;
+}
+EXPORT_SYMBOL_GPL(iio_st_read_channel_raw);
+
+int iio_st_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 = chan->indio_dev->info->read_raw(chan->indio_dev,
+                                              chan->channel,
+                                              val, val2,
+                                              IIO_CHAN_INFO_SCALE);
+err_unlock:
+        mutex_unlock(&chan->indio_dev->info_exist_lock);
+
+        return ret;
+}
+EXPORT_SYMBOL_GPL(iio_st_read_channel_scale);
+
+int iio_st_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_st_get_channel_type);