1 files changed, 320 insertions, 267 deletions

diff --git a/drivers/staging/iio/industrialio-ring.c b/drivers/staging/iio/industrialio-ring.c
index bd4373ae066..843eb82a69b 100644
--- a/drivers/staging/iio/industrialio-ring.c
+++ b/drivers/staging/iio/industrialio-ring.c
@@ -18,37 +18,11 @@
 #include <linux/fs.h>
 #include <linux/cdev.h>
 #include <linux/slab.h>
+#include <linux/poll.h>
 
 #include "iio.h"
 #include "ring_generic.h"
 
-int iio_push_ring_event(struct iio_ring_buffer *ring_buf,
-		       int event_code,
-		       s64 timestamp)
-{
-	return __iio_push_event(&ring_buf->ev_int,
-			       event_code,
-			       timestamp,
-			       &ring_buf->shared_ev_pointer);
-}
-EXPORT_SYMBOL(iio_push_ring_event);
-
-int iio_push_or_escallate_ring_event(struct iio_ring_buffer *ring_buf,
-				    int event_code,
-				    s64 timestamp)
-{
-	if (ring_buf->shared_ev_pointer.ev_p)
-		__iio_change_event(ring_buf->shared_ev_pointer.ev_p,
-				   event_code,
-				   timestamp);
-	else
-		return iio_push_ring_event(ring_buf,
-					  event_code,
-					  timestamp);
-	return 0;
-}
-EXPORT_SYMBOL(iio_push_or_escallate_ring_event);
-
 /**
  * iio_ring_open() - chrdev file open for ring buffer access
  *
@@ -62,8 +36,8 @@ static int iio_ring_open(struct inode *inode, struct file *filp)
 	struct iio_ring_buffer *rb = hand->private;
 
 	filp->private_data = hand->private;
-	if (rb->access.mark_in_use)
-		rb->access.mark_in_use(rb);
+	if (rb->access->mark_in_use)
+		rb->access->mark_in_use(rb);
 
 	return 0;
 }
@@ -81,184 +55,316 @@ static int iio_ring_release(struct inode *inode, struct file *filp)
 	struct iio_ring_buffer *rb = hand->private;
 
 	clear_bit(IIO_BUSY_BIT_POS, &rb->access_handler.flags);
-	if (rb->access.unmark_in_use)
-		rb->access.unmark_in_use(rb);
+	if (rb->access->unmark_in_use)
+		rb->access->unmark_in_use(rb);
 
 	return 0;
 }
 
 /**
- * iio_ring_rip_outer() - chrdev read for ring buffer access
+ * iio_ring_read_first_n_outer() - chrdev read for ring buffer access
  *
  * This function relies on all ring buffer implementations having an
  * iio_ring _bufer as their first element.
  **/
-static ssize_t iio_ring_rip_outer(struct file *filp, char __user *buf,
-				  size_t count, loff_t *f_ps)
+static ssize_t iio_ring_read_first_n_outer(struct file *filp, char __user *buf,
+				  size_t n, loff_t *f_ps)
 {
 	struct iio_ring_buffer *rb = filp->private_data;
-	int ret, dead_offset;
 
-	/* rip lots must exist. */
-	if (!rb->access.rip_lots)
+	if (!rb->access->read_first_n)
 		return -EINVAL;
-	ret = rb->access.rip_lots(rb, count, buf, &dead_offset);
+	return rb->access->read_first_n(rb, n, buf);
+}
 
-	return ret;
+/**
+ * iio_ring_poll() - poll the ring to find out if it has data
+ */
+static unsigned int iio_ring_poll(struct file *filp,
+				  struct poll_table_struct *wait)
+{
+	struct iio_ring_buffer *rb = filp->private_data;
+
+	poll_wait(filp, &rb->pollq, wait);
+	if (rb->stufftoread)
+		return POLLIN | POLLRDNORM;
+	/* need a way of knowing if there may be enough data... */
+	return 0;
 }
 
 static const struct file_operations iio_ring_fileops = {
-	.read = iio_ring_rip_outer,
+	.read = iio_ring_read_first_n_outer,
 	.release = iio_ring_release,
 	.open = iio_ring_open,
+	.poll = iio_ring_poll,
 	.owner = THIS_MODULE,
 	.llseek = noop_llseek,
 };
 
-/**
- * __iio_request_ring_buffer_event_chrdev() - allocate ring event chrdev
- * @buf:	ring buffer whose event chrdev we are allocating
- * @id:		id of this ring buffer (typically 0)
- * @owner:	the module who owns the ring buffer (for ref counting)
- * @dev:	device with which the chrdev is associated
- **/
-static inline int
-__iio_request_ring_buffer_event_chrdev(struct iio_ring_buffer *buf,
-				       int id,
-				       struct module *owner,
-				       struct device *dev)
-{
-	int ret;
-
-	snprintf(buf->ev_int._name, sizeof(buf->ev_int._name),
-		 "%s:event%d",
-		 dev_name(&buf->dev),
-		 id);
-	ret = iio_setup_ev_int(&(buf->ev_int),
-			       buf->ev_int._name,
-			       owner,
-			       dev);
-	if (ret)
-		goto error_ret;
-	return 0;
-
-error_ret:
-	return ret;
-}
-
-static inline void
-__iio_free_ring_buffer_event_chrdev(struct iio_ring_buffer *buf)
-{
-	iio_free_ev_int(&(buf->ev_int));
-}
-
-static void iio_ring_access_release(struct device *dev)
+void iio_ring_access_release(struct device *dev)
 {
 	struct iio_ring_buffer *buf
-		= access_dev_to_iio_ring_buffer(dev);
+		= container_of(dev, struct iio_ring_buffer, dev);
 	cdev_del(&buf->access_handler.chrdev);
 	iio_device_free_chrdev_minor(MINOR(dev->devt));
 }
-
-static struct device_type iio_ring_access_type = {
-	.release = iio_ring_access_release,
-};
+EXPORT_SYMBOL(iio_ring_access_release);
 
 static inline int
-__iio_request_ring_buffer_access_chrdev(struct iio_ring_buffer *buf,
-					int id,
-					struct module *owner)
+__iio_request_ring_buffer_chrdev(struct iio_ring_buffer *buf,
+				 struct module *owner,
+				 int id)
 {
-	int ret, minor;
+	int ret;
 
 	buf->access_handler.flags = 0;
+	buf->dev.bus = &iio_bus_type;
+	device_initialize(&buf->dev);
 
-	buf->access_dev.parent = &buf->dev;
-	buf->access_dev.bus = &iio_bus_type;
-	buf->access_dev.type = &iio_ring_access_type;
-	device_initialize(&buf->access_dev);
-
-	minor = iio_device_get_chrdev_minor();
-	if (minor < 0) {
-		ret = minor;
+	ret = iio_device_get_chrdev_minor();
+	if (ret < 0)
 		goto error_device_put;
-	}
-	buf->access_dev.devt = MKDEV(MAJOR(iio_devt), minor);
 
-
-	buf->access_id = id;
-
-	dev_set_name(&buf->access_dev, "%s:access%d",
-		     dev_name(&buf->dev),
-		     buf->access_id);
-	ret = device_add(&buf->access_dev);
+	buf->dev.devt = MKDEV(MAJOR(iio_devt), ret);
+	dev_set_name(&buf->dev, "%s:buffer%d",
+		     dev_name(buf->dev.parent),
+		     id);
+	ret = device_add(&buf->dev);
 	if (ret < 0) {
-		printk(KERN_ERR "failed to add the ring access dev\n");
+		printk(KERN_ERR "failed to add the ring dev\n");
 		goto error_device_put;
 	}
-
 	cdev_init(&buf->access_handler.chrdev, &iio_ring_fileops);
 	buf->access_handler.chrdev.owner = owner;
-
-	ret = cdev_add(&buf->access_handler.chrdev, buf->access_dev.devt, 1);
+	ret = cdev_add(&buf->access_handler.chrdev, buf->dev.devt, 1);
 	if (ret) {
-		printk(KERN_ERR "failed to allocate ring access chrdev\n");
+		printk(KERN_ERR "failed to allocate ring chrdev\n");
 		goto error_device_unregister;
 	}
 	return 0;
 
 error_device_unregister:
-	device_unregister(&buf->access_dev);
+	device_unregister(&buf->dev);
 error_device_put:
-	put_device(&buf->access_dev);
+	put_device(&buf->dev);
 
 	return ret;
 }
 
-static void __iio_free_ring_buffer_access_chrdev(struct iio_ring_buffer *buf)
+static void __iio_free_ring_buffer_chrdev(struct iio_ring_buffer *buf)
 {
-	device_unregister(&buf->access_dev);
+	device_unregister(&buf->dev);
 }
 
 void iio_ring_buffer_init(struct iio_ring_buffer *ring,
 			  struct iio_dev *dev_info)
 {
-	if (ring->access.mark_param_change)
-		ring->access.mark_param_change(ring);
 	ring->indio_dev = dev_info;
-	ring->ev_int.private = ring;
 	ring->access_handler.private = ring;
-	ring->shared_ev_pointer.ev_p = NULL;
-	spin_lock_init(&ring->shared_ev_pointer.lock);
+	init_waitqueue_head(&ring->pollq);
 }
 EXPORT_SYMBOL(iio_ring_buffer_init);
 
-int iio_ring_buffer_register(struct iio_ring_buffer *ring, int id)
+static ssize_t iio_show_scan_index(struct device *dev,
+				   struct device_attribute *attr,
+				   char *buf)
+{
+	return sprintf(buf, "%u\n", to_iio_dev_attr(attr)->c->scan_index);
+}
+
+static ssize_t iio_show_fixed_type(struct device *dev,
+				   struct device_attribute *attr,
+				   char *buf)
+{
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+	return sprintf(buf, "%c%d/%d>>%u\n",
+		       this_attr->c->scan_type.sign,
+		       this_attr->c->scan_type.realbits,
+		       this_attr->c->scan_type.storagebits,
+		       this_attr->c->scan_type.shift);
+}
+
+static ssize_t iio_scan_el_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
 {
 	int ret;
+	struct iio_ring_buffer *ring = dev_get_drvdata(dev);
+
+	ret = iio_scan_mask_query(ring, to_iio_dev_attr(attr)->address);
+	if (ret < 0)
+		return ret;
+	return sprintf(buf, "%d\n", ret);
+}
 
-	ring->id = id;
+static int iio_scan_mask_clear(struct iio_ring_buffer *ring, int bit)
+{
+	if (bit > IIO_MAX_SCAN_LENGTH)
+		return -EINVAL;
+	ring->scan_mask &= ~(1 << bit);
+	ring->scan_count--;
+	return 0;
+}
+
+static ssize_t iio_scan_el_store(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf,
+				 size_t len)
+{
+	int ret = 0;
+	bool state;
+	struct iio_ring_buffer *ring = dev_get_drvdata(dev);
+	struct iio_dev *indio_dev = ring->indio_dev;
+	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+
+	state = !(buf[0] == '0');
+	mutex_lock(&indio_dev->mlock);
+	if (indio_dev->currentmode == INDIO_RING_TRIGGERED) {
+		ret = -EBUSY;
+		goto error_ret;
+	}
+	ret = iio_scan_mask_query(ring, this_attr->address);
+	if (ret < 0)
+		goto error_ret;
+	if (!state && ret) {
+		ret = iio_scan_mask_clear(ring, this_attr->address);
+		if (ret)
+			goto error_ret;
+	} else if (state && !ret) {
+		ret = iio_scan_mask_set(ring, this_attr->address);
+		if (ret)
+			goto error_ret;
+	}
+
+error_ret:
+	mutex_unlock(&indio_dev->mlock);
+
+	return ret ? ret : len;
+
+}
+
+static ssize_t iio_scan_el_ts_show(struct device *dev,
+				   struct device_attribute *attr,
+				   char *buf)
+{
+	struct iio_ring_buffer *ring = dev_get_drvdata(dev);
+	return sprintf(buf, "%d\n", ring->scan_timestamp);
+}
+
+static ssize_t iio_scan_el_ts_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf,
+				    size_t len)
+{
+	int ret = 0;
+	struct iio_ring_buffer *ring = dev_get_drvdata(dev);
+	struct iio_dev *indio_dev = ring->indio_dev;
+	bool state;
+	state = !(buf[0] == '0');
+	mutex_lock(&indio_dev->mlock);
+	if (indio_dev->currentmode == INDIO_RING_TRIGGERED) {
+		ret = -EBUSY;
+		goto error_ret;
+	}
+	ring->scan_timestamp = state;
+error_ret:
+	mutex_unlock(&indio_dev->mlock);
 
-	dev_set_name(&ring->dev, "%s:buffer%d",
-		     dev_name(ring->dev.parent),
-		     ring->id);
-	ret = device_add(&ring->dev);
+	return ret ? ret : len;
+}
+
+static int iio_ring_add_channel_sysfs(struct iio_ring_buffer *ring,
+				      const struct iio_chan_spec *chan)
+{
+	int ret;
+
+	ret = __iio_add_chan_devattr("index", "scan_elements",
+				     chan,
+				     &iio_show_scan_index,
+				     NULL,
+				     0,
+				     0,
+				     &ring->dev,
+				     &ring->scan_el_dev_attr_list);
 	if (ret)
 		goto error_ret;
 
-	ret = __iio_request_ring_buffer_event_chrdev(ring,
-						     0,
-						     ring->owner,
-						     &ring->dev);
+	ret = __iio_add_chan_devattr("type", "scan_elements",
+				     chan,
+				     &iio_show_fixed_type,
+				     NULL,
+				     0,
+				     0,
+				     &ring->dev,
+				     &ring->scan_el_dev_attr_list);
 	if (ret)
-		goto error_remove_device;
+		goto error_ret;
+
+	if (chan->type != IIO_TIMESTAMP)
+		ret = __iio_add_chan_devattr("en", "scan_elements",
+					     chan,
+					     &iio_scan_el_show,
+					     &iio_scan_el_store,
+					     chan->scan_index,
+					     0,
+					     &ring->dev,
+					     &ring->scan_el_dev_attr_list);
+	else
+		ret = __iio_add_chan_devattr("en", "scan_elements",
+					     chan,
+					     &iio_scan_el_ts_show,
+					     &iio_scan_el_ts_store,
+					     chan->scan_index,
+					     0,
+					     &ring->dev,
+					     &ring->scan_el_dev_attr_list);
+error_ret:
+	return ret;
+}
+
+static void iio_ring_remove_and_free_scan_dev_attr(struct iio_ring_buffer *ring,
+						   struct iio_dev_attr *p)
+{
+	sysfs_remove_file_from_group(&ring->dev.kobj,
+				     &p->dev_attr.attr, "scan_elements");
+	kfree(p->dev_attr.attr.name);
+	kfree(p);
+}
+
+static struct attribute *iio_scan_el_dummy_attrs[] = {
+	NULL
+};
+
+static struct attribute_group iio_scan_el_dummy_group = {
+	.name = "scan_elements",
+	.attrs = iio_scan_el_dummy_attrs
+};
+
+static void __iio_ring_attr_cleanup(struct iio_ring_buffer *ring)
+{
+	struct iio_dev_attr *p, *n;
+	int anydynamic = !list_empty(&ring->scan_el_dev_attr_list);
+	list_for_each_entry_safe(p, n,
+				 &ring->scan_el_dev_attr_list, l)
+		iio_ring_remove_and_free_scan_dev_attr(ring, p);
+
+	if (ring->scan_el_attrs)
+		sysfs_remove_group(&ring->dev.kobj,
+				   ring->scan_el_attrs);
+	else if (anydynamic)
+		sysfs_remove_group(&ring->dev.kobj,
+				   &iio_scan_el_dummy_group);
+}
 
-	ret = __iio_request_ring_buffer_access_chrdev(ring,
-						      0,
-						      ring->owner);
+int iio_ring_buffer_register_ex(struct iio_ring_buffer *ring, int id,
+				const struct iio_chan_spec *channels,
+				int num_channels)
+{
+	int ret, i;
 
+	ret = __iio_request_ring_buffer_chrdev(ring, ring->owner, id);
 	if (ret)
-		goto error_free_ring_buffer_event_chrdev;
+		goto error_ret;
 
 	if (ring->scan_el_attrs) {
 		ret = sysfs_create_group(&ring->dev.kobj,
@@ -266,29 +372,39 @@ int iio_ring_buffer_register(struct iio_ring_buffer *ring, int id)
 		if (ret) {
 			dev_err(&ring->dev,
 				"Failed to add sysfs scan elements\n");
-			goto error_free_ring_buffer_event_chrdev;
+			goto error_free_ring_buffer_chrdev;
 		}
+	} else if (channels) {
+		ret = sysfs_create_group(&ring->dev.kobj,
+					 &iio_scan_el_dummy_group);
+		if (ret)
+			goto error_free_ring_buffer_chrdev;
 	}
 
-	return ret;
-error_free_ring_buffer_event_chrdev:
-	__iio_free_ring_buffer_event_chrdev(ring);
-error_remove_device:
-	device_del(&ring->dev);
+	INIT_LIST_HEAD(&ring->scan_el_dev_attr_list);
+	if (channels) {
+		/* new magic */
+		for (i = 0; i < num_channels; i++) {
+			ret = iio_ring_add_channel_sysfs(ring, &channels[i]);
+			if (ret < 0)
+				goto error_cleanup_dynamic;
+		}
+	}
+
+	return 0;
+error_cleanup_dynamic:
+	__iio_ring_attr_cleanup(ring);
+error_free_ring_buffer_chrdev:
+	__iio_free_ring_buffer_chrdev(ring);
 error_ret:
 	return ret;
 }
-EXPORT_SYMBOL(iio_ring_buffer_register);
+EXPORT_SYMBOL(iio_ring_buffer_register_ex);
 
 void iio_ring_buffer_unregister(struct iio_ring_buffer *ring)
 {
-	if (ring->scan_el_attrs)
-		sysfs_remove_group(&ring->dev.kobj,
-				   ring->scan_el_attrs);
-
-	__iio_free_ring_buffer_access_chrdev(ring);
-	__iio_free_ring_buffer_event_chrdev(ring);
-	device_del(&ring->dev);
+	__iio_ring_attr_cleanup(ring);
+	__iio_free_ring_buffer_chrdev(ring);
 }
 EXPORT_SYMBOL(iio_ring_buffer_unregister);
 
@@ -296,14 +412,13 @@ ssize_t iio_read_ring_length(struct device *dev,
 			     struct device_attribute *attr,
 			     char *buf)
 {
-	int len = 0;
 	struct iio_ring_buffer *ring = dev_get_drvdata(dev);
 
-	if (ring->access.get_length)
-		len = sprintf(buf, "%d\n",
-			      ring->access.get_length(ring));
+	if (ring->access->get_length)
+		return sprintf(buf, "%d\n",
+			       ring->access->get_length(ring));
 
-	return len;
+	return 0;
 }
 EXPORT_SYMBOL(iio_read_ring_length);
 
@@ -315,18 +430,19 @@ ssize_t iio_write_ring_length(struct device *dev,
 	int ret;
 	ulong val;
 	struct iio_ring_buffer *ring = dev_get_drvdata(dev);
+
 	ret = strict_strtoul(buf, 10, &val);
 	if (ret)
 		return ret;
 
-	if (ring->access.get_length)
-		if (val == ring->access.get_length(ring))
+	if (ring->access->get_length)
+		if (val == ring->access->get_length(ring))
 			return len;
 
-	if (ring->access.set_length) {
-		ring->access.set_length(ring, val);
-		if (ring->access.mark_param_change)
-			ring->access.mark_param_change(ring);
+	if (ring->access->set_length) {
+		ring->access->set_length(ring, val);
+		if (ring->access->mark_param_change)
+			ring->access->mark_param_change(ring);
 	}
 
 	return len;
@@ -337,14 +453,13 @@ ssize_t iio_read_ring_bytes_per_datum(struct device *dev,
 			  struct device_attribute *attr,
 			  char *buf)
 {
-	int len = 0;
 	struct iio_ring_buffer *ring = dev_get_drvdata(dev);
 
-	if (ring->access.get_bytes_per_datum)
-		len = sprintf(buf, "%d\n",
-			      ring->access.get_bytes_per_datum(ring));
+	if (ring->access->get_bytes_per_datum)
+		return sprintf(buf, "%d\n",
+			       ring->access->get_bytes_per_datum(ring));
 
-	return len;
+	return 0;
 }
 EXPORT_SYMBOL(iio_read_ring_bytes_per_datum);
 
@@ -368,8 +483,8 @@ ssize_t iio_store_ring_enable(struct device *dev,
 		goto done;
 	}
 	if (requested_state) {
-		if (ring->preenable) {
-			ret = ring->preenable(dev_info);
+		if (ring->setup_ops->preenable) {
+			ret = ring->setup_ops->preenable(dev_info);
 			if (ret) {
 				printk(KERN_ERR
 				       "Buffer not started:"
@@ -377,8 +492,8 @@ ssize_t iio_store_ring_enable(struct device *dev,
 				goto error_ret;
 			}
 		}
-		if (ring->access.request_update) {
-			ret = ring->access.request_update(ring);
+		if (ring->access->request_update) {
+			ret = ring->access->request_update(ring);
 			if (ret) {
 				printk(KERN_INFO
 				       "Buffer not started:"
@@ -386,16 +501,16 @@ ssize_t iio_store_ring_enable(struct device *dev,
 				goto error_ret;
 			}
 		}
-		if (ring->access.mark_in_use)
-			ring->access.mark_in_use(ring);
+		if (ring->access->mark_in_use)
+			ring->access->mark_in_use(ring);
 		/* Definitely possible for devices to support both of these.*/
 		if (dev_info->modes & INDIO_RING_TRIGGERED) {
 			if (!dev_info->trig) {
 				printk(KERN_INFO
 				       "Buffer not started: no trigger\n");
 				ret = -EINVAL;
-				if (ring->access.unmark_in_use)
-					ring->access.unmark_in_use(ring);
+				if (ring->access->unmark_in_use)
+					ring->access->unmark_in_use(ring);
 				goto error_ret;
 			}
 			dev_info->currentmode = INDIO_RING_TRIGGERED;
@@ -406,32 +521,31 @@ ssize_t iio_store_ring_enable(struct device *dev,
 			goto error_ret;
 		}
 
-		if (ring->postenable) {
-
-			ret = ring->postenable(dev_info);
+		if (ring->setup_ops->postenable) {
+			ret = ring->setup_ops->postenable(dev_info);
 			if (ret) {
 				printk(KERN_INFO
 				       "Buffer not started:"
 				       "postenable failed\n");
-				if (ring->access.unmark_in_use)
-					ring->access.unmark_in_use(ring);
+				if (ring->access->unmark_in_use)
+					ring->access->unmark_in_use(ring);
 				dev_info->currentmode = previous_mode;
-				if (ring->postdisable)
-					ring->postdisable(dev_info);
+				if (ring->setup_ops->postdisable)
+					ring->setup_ops->postdisable(dev_info);
 				goto error_ret;
 			}
 		}
 	} else {
-		if (ring->predisable) {
-			ret = ring->predisable(dev_info);
+		if (ring->setup_ops->predisable) {
+			ret = ring->setup_ops->predisable(dev_info);
 			if (ret)
 				goto error_ret;
 		}
-		if (ring->access.unmark_in_use)
-			ring->access.unmark_in_use(ring);
+		if (ring->access->unmark_in_use)
+			ring->access->unmark_in_use(ring);
 		dev_info->currentmode = INDIO_DIRECT_MODE;
-		if (ring->postdisable) {
-			ret = ring->postdisable(dev_info);
+		if (ring->setup_ops->postdisable) {
+			ret = ring->setup_ops->postdisable(dev_info);
 			if (ret)
 				goto error_ret;
 		}
@@ -445,6 +559,7 @@ error_ret:
 	return ret;
 }
 EXPORT_SYMBOL(iio_store_ring_enable);
+
 ssize_t iio_show_ring_enable(struct device *dev,
 				    struct device_attribute *attr,
 				    char *buf)
@@ -455,89 +570,27 @@ ssize_t iio_show_ring_enable(struct device *dev,
 }
 EXPORT_SYMBOL(iio_show_ring_enable);
 
-ssize_t iio_scan_el_show(struct device *dev,
-			 struct device_attribute *attr,
-			 char *buf)
-{
-	int ret;
-	struct iio_ring_buffer *ring = dev_get_drvdata(dev);
-	struct iio_scan_el *this_el = to_iio_scan_el(attr);
-
-	ret = iio_scan_mask_query(ring, this_el->number);
-	if (ret < 0)
-		return ret;
-	return sprintf(buf, "%d\n", ret);
-}
-EXPORT_SYMBOL(iio_scan_el_show);
-
-ssize_t iio_scan_el_store(struct device *dev,
-			  struct device_attribute *attr,
-			  const char *buf,
-			  size_t len)
-{
-	int ret = 0;
-	bool state;
-	struct iio_ring_buffer *ring = dev_get_drvdata(dev);
-	struct iio_dev *indio_dev = ring->indio_dev;
-	struct iio_scan_el *this_el = to_iio_scan_el(attr);
-
-	state = !(buf[0] == '0');
-	mutex_lock(&indio_dev->mlock);
-	if (indio_dev->currentmode == INDIO_RING_TRIGGERED) {
-		ret = -EBUSY;
-		goto error_ret;
-	}
-	ret = iio_scan_mask_query(ring, this_el->number);
-	if (ret < 0)
-		goto error_ret;
-	if (!state && ret) {
-		ret = iio_scan_mask_clear(ring, this_el->number);
-		if (ret)
-			goto error_ret;
-	} else if (state && !ret) {
-		ret = iio_scan_mask_set(ring, this_el->number);
-		if (ret)
-			goto error_ret;
-	}
-	if (this_el->set_state)
-		ret = this_el->set_state(this_el, indio_dev, state);
-error_ret:
-	mutex_unlock(&indio_dev->mlock);
-
-	return ret ? ret : len;
-
-}
-EXPORT_SYMBOL(iio_scan_el_store);
-
-ssize_t iio_scan_el_ts_show(struct device *dev,
-			    struct device_attribute *attr,
-			    char *buf)
-{
-	struct iio_ring_buffer *ring = dev_get_drvdata(dev);
-	return sprintf(buf, "%d\n", ring->scan_timestamp);
-}
-EXPORT_SYMBOL(iio_scan_el_ts_show);
-
-ssize_t iio_scan_el_ts_store(struct device *dev,
-			     struct device_attribute *attr,
-			     const char *buf,
-			     size_t len)
+int iio_sw_ring_preenable(struct iio_dev *indio_dev)
 {
-	int ret = 0;
-	struct iio_ring_buffer *ring = dev_get_drvdata(dev);
-	struct iio_dev *indio_dev = ring->indio_dev;
-	bool state;
-	state = !(buf[0] == '0');
-	mutex_lock(&indio_dev->mlock);
-	if (indio_dev->currentmode == INDIO_RING_TRIGGERED) {
-		ret = -EBUSY;
-		goto error_ret;
-	}
-	ring->scan_timestamp = state;
-error_ret:
-	mutex_unlock(&indio_dev->mlock);
+	struct iio_ring_buffer *ring = indio_dev->ring;
+	size_t size;
+	dev_dbg(&indio_dev->dev, "%s\n", __func__);
+	/* Check if there are any scan elements enabled, if not fail*/
+	if (!(ring->scan_count || ring->scan_timestamp))
+		return -EINVAL;
+	if (ring->scan_timestamp)
+		if (ring->scan_count)
+			/* Timestamp (aligned to s64) and data */
+			size = (((ring->scan_count * ring->bpe)
+					+ sizeof(s64) - 1)
+				& ~(sizeof(s64) - 1))
+				+ sizeof(s64);
+		else /* Timestamp only  */
+			size = sizeof(s64);
+	else /* Data only */
+		size = ring->scan_count * ring->bpe;
+	ring->access->set_bytes_per_datum(ring, size);
 
-	return ret ? ret : len;
+	return 0;
 }
-EXPORT_SYMBOL(iio_scan_el_ts_store);
-
+EXPORT_SYMBOL(iio_sw_ring_preenable);