1 files changed, 217 insertions, 193 deletions

diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index f971f79103ec..71333140d42c 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -178,6 +178,80 @@ static ssize_t iio_scan_el_show(struct device *dev,
 	return sprintf(buf, "%d\n", ret);
 }
 
+/* Note NULL used as error indicator as it doesn't make sense. */
+static const unsigned long *iio_scan_mask_match(const unsigned long *av_masks,
+					  unsigned int masklength,
+					  const unsigned long *mask)
+{
+	if (bitmap_empty(mask, masklength))
+		return NULL;
+	while (*av_masks) {
+		if (bitmap_subset(mask, av_masks, masklength))
+			return av_masks;
+		av_masks += BITS_TO_LONGS(masklength);
+	}
+	return NULL;
+}
+
+static bool iio_validate_scan_mask(struct iio_dev *indio_dev,
+	const unsigned long *mask)
+{
+	if (!indio_dev->setup_ops->validate_scan_mask)
+		return true;
+
+	return indio_dev->setup_ops->validate_scan_mask(indio_dev, mask);
+}
+
+/**
+ * iio_scan_mask_set() - set particular bit in the scan mask
+ * @indio_dev: the iio device
+ * @buffer: the buffer whose scan mask we are interested in
+ * @bit: the bit to be set.
+ *
+ * Note that at this point we have no way of knowing what other
+ * buffers might request, hence this code only verifies that the
+ * individual buffers request is plausible.
+ */
+static int iio_scan_mask_set(struct iio_dev *indio_dev,
+		      struct iio_buffer *buffer, int bit)
+{
+	const unsigned long *mask;
+	unsigned long *trialmask;
+
+	trialmask = kmalloc(sizeof(*trialmask)*
+			    BITS_TO_LONGS(indio_dev->masklength),
+			    GFP_KERNEL);
+
+	if (trialmask == NULL)
+		return -ENOMEM;
+	if (!indio_dev->masklength) {
+		WARN_ON("Trying to set scanmask prior to registering buffer\n");
+		goto err_invalid_mask;
+	}
+	bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength);
+	set_bit(bit, trialmask);
+
+	if (!iio_validate_scan_mask(indio_dev, trialmask))
+		goto err_invalid_mask;
+
+	if (indio_dev->available_scan_masks) {
+		mask = iio_scan_mask_match(indio_dev->available_scan_masks,
+					   indio_dev->masklength,
+					   trialmask);
+		if (!mask)
+			goto err_invalid_mask;
+	}
+	bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength);
+
+	kfree(trialmask);
+
+	return 0;
+
+err_invalid_mask:
+	kfree(trialmask);
+	return -EINVAL;
+}
+
 static int iio_scan_mask_clear(struct iio_buffer *buffer, int bit)
 {
 	clear_bit(bit, buffer->scan_mask);
@@ -309,115 +383,19 @@ static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev,
 	return ret;
 }
 
-static const char * const iio_scan_elements_group_name = "scan_elements";
-
-int iio_buffer_register(struct iio_dev *indio_dev,
-			const struct iio_chan_spec *channels,
-			int num_channels)
-{
-	struct iio_dev_attr *p;
-	struct attribute **attr;
-	struct iio_buffer *buffer = indio_dev->buffer;
-	int ret, i, attrn, attrcount, attrcount_orig = 0;
-
-	if (buffer->attrs)
-		indio_dev->groups[indio_dev->groupcounter++] = buffer->attrs;
-
-	if (buffer->scan_el_attrs != NULL) {
-		attr = buffer->scan_el_attrs->attrs;
-		while (*attr++ != NULL)
-			attrcount_orig++;
-	}
-	attrcount = attrcount_orig;
-	INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list);
-	if (channels) {
-		/* new magic */
-		for (i = 0; i < num_channels; i++) {
-			if (channels[i].scan_index < 0)
-				continue;
-
-			/* Establish necessary mask length */
-			if (channels[i].scan_index >
-			    (int)indio_dev->masklength - 1)
-				indio_dev->masklength
-					= channels[i].scan_index + 1;
-
-			ret = iio_buffer_add_channel_sysfs(indio_dev,
-							 &channels[i]);
-			if (ret < 0)
-				goto error_cleanup_dynamic;
-			attrcount += ret;
-			if (channels[i].type == IIO_TIMESTAMP)
-				indio_dev->scan_index_timestamp =
-					channels[i].scan_index;
-		}
-		if (indio_dev->masklength && buffer->scan_mask == NULL) {
-			buffer->scan_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength),
-						    sizeof(*buffer->scan_mask),
-						    GFP_KERNEL);
-			if (buffer->scan_mask == NULL) {
-				ret = -ENOMEM;
-				goto error_cleanup_dynamic;
-			}
-		}
-	}
-
-	buffer->scan_el_group.name = iio_scan_elements_group_name;
-
-	buffer->scan_el_group.attrs = kcalloc(attrcount + 1,
-					      sizeof(buffer->scan_el_group.attrs[0]),
-					      GFP_KERNEL);
-	if (buffer->scan_el_group.attrs == NULL) {
-		ret = -ENOMEM;
-		goto error_free_scan_mask;
-	}
-	if (buffer->scan_el_attrs)
-		memcpy(buffer->scan_el_group.attrs, buffer->scan_el_attrs,
-		       sizeof(buffer->scan_el_group.attrs[0])*attrcount_orig);
-	attrn = attrcount_orig;
-
-	list_for_each_entry(p, &buffer->scan_el_dev_attr_list, l)
-		buffer->scan_el_group.attrs[attrn++] = &p->dev_attr.attr;
-	indio_dev->groups[indio_dev->groupcounter++] = &buffer->scan_el_group;
-
-	return 0;
-
-error_free_scan_mask:
-	kfree(buffer->scan_mask);
-error_cleanup_dynamic:
-	iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list);
-
-	return ret;
-}
-EXPORT_SYMBOL(iio_buffer_register);
-
-void iio_buffer_unregister(struct iio_dev *indio_dev)
-{
-	kfree(indio_dev->buffer->scan_mask);
-	kfree(indio_dev->buffer->scan_el_group.attrs);
-	iio_free_chan_devattr_list(&indio_dev->buffer->scan_el_dev_attr_list);
-}
-EXPORT_SYMBOL(iio_buffer_unregister);
-
-ssize_t iio_buffer_read_length(struct device *dev,
-			       struct device_attribute *attr,
-			       char *buf)
+static ssize_t iio_buffer_read_length(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf)
 {
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct iio_buffer *buffer = indio_dev->buffer;
 
-	if (buffer->access->get_length)
-		return sprintf(buf, "%d\n",
-			       buffer->access->get_length(buffer));
-
-	return 0;
+	return sprintf(buf, "%d\n", buffer->length);
 }
-EXPORT_SYMBOL(iio_buffer_read_length);
 
-ssize_t iio_buffer_write_length(struct device *dev,
-				struct device_attribute *attr,
-				const char *buf,
-				size_t len)
+static ssize_t iio_buffer_write_length(struct device *dev,
+				       struct device_attribute *attr,
+				       const char *buf, size_t len)
 {
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct iio_buffer *buffer = indio_dev->buffer;
@@ -428,47 +406,28 @@ ssize_t iio_buffer_write_length(struct device *dev,
 	if (ret)
 		return ret;
 
-	if (buffer->access->get_length)
-		if (val == buffer->access->get_length(buffer))
-			return len;
+	if (val == buffer->length)
+		return len;
 
 	mutex_lock(&indio_dev->mlock);
 	if (iio_buffer_is_active(indio_dev->buffer)) {
 		ret = -EBUSY;
 	} else {
-		if (buffer->access->set_length)
-			buffer->access->set_length(buffer, val);
+		buffer->access->set_length(buffer, val);
 		ret = 0;
 	}
 	mutex_unlock(&indio_dev->mlock);
 
 	return ret ? ret : len;
 }
-EXPORT_SYMBOL(iio_buffer_write_length);
 
-ssize_t iio_buffer_show_enable(struct device *dev,
-			       struct device_attribute *attr,
-			       char *buf)
+static ssize_t iio_buffer_show_enable(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf)
 {
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	return sprintf(buf, "%d\n", iio_buffer_is_active(indio_dev->buffer));
 }
-EXPORT_SYMBOL(iio_buffer_show_enable);
-
-/* Note NULL used as error indicator as it doesn't make sense. */
-static const unsigned long *iio_scan_mask_match(const unsigned long *av_masks,
-					  unsigned int masklength,
-					  const unsigned long *mask)
-{
-	if (bitmap_empty(mask, masklength))
-		return NULL;
-	while (*av_masks) {
-		if (bitmap_subset(mask, av_masks, masklength))
-			return av_masks;
-		av_masks += BITS_TO_LONGS(masklength);
-	}
-	return NULL;
-}
 
 static int iio_compute_scan_bytes(struct iio_dev *indio_dev,
 				const unsigned long *mask, bool timestamp)
@@ -680,6 +639,8 @@ static int __iio_update_buffers(struct iio_dev *indio_dev,
 		indio_dev->currentmode = INDIO_BUFFER_TRIGGERED;
 	} else if (indio_dev->modes & INDIO_BUFFER_HARDWARE) {
 		indio_dev->currentmode = INDIO_BUFFER_HARDWARE;
+	} else if (indio_dev->modes & INDIO_BUFFER_SOFTWARE) {
+		indio_dev->currentmode = INDIO_BUFFER_SOFTWARE;
 	} else { /* Should never be reached */
 		ret = -EINVAL;
 		goto error_run_postdisable;
@@ -755,10 +716,10 @@ out_unlock:
 }
 EXPORT_SYMBOL_GPL(iio_update_buffers);
 
-ssize_t iio_buffer_store_enable(struct device *dev,
-				struct device_attribute *attr,
-				const char *buf,
-				size_t len)
+static ssize_t iio_buffer_store_enable(struct device *dev,
+				       struct device_attribute *attr,
+				       const char *buf,
+				       size_t len)
 {
 	int ret;
 	bool requested_state;
@@ -790,83 +751,146 @@ done:
 	mutex_unlock(&indio_dev->mlock);
 	return (ret < 0) ? ret : len;
 }
-EXPORT_SYMBOL(iio_buffer_store_enable);
 
-/**
- * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected
- * @indio_dev: the iio device
- * @mask: scan mask to be checked
- *
- * Return true if exactly one bit is set in the scan mask, false otherwise. It
- * can be used for devices where only one channel can be active for sampling at
- * a time.
- */
-bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev,
-	const unsigned long *mask)
-{
-	return bitmap_weight(mask, indio_dev->masklength) == 1;
-}
-EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot);
-
-static bool iio_validate_scan_mask(struct iio_dev *indio_dev,
-	const unsigned long *mask)
-{
-	if (!indio_dev->setup_ops->validate_scan_mask)
-		return true;
+static const char * const iio_scan_elements_group_name = "scan_elements";
 
-	return indio_dev->setup_ops->validate_scan_mask(indio_dev, mask);
-}
+static DEVICE_ATTR(length, S_IRUGO | S_IWUSR, iio_buffer_read_length,
+		   iio_buffer_write_length);
+static struct device_attribute dev_attr_length_ro = __ATTR(length,
+	S_IRUGO, iio_buffer_read_length, NULL);
+static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR,
+		   iio_buffer_show_enable, iio_buffer_store_enable);
 
-/**
- * iio_scan_mask_set() - set particular bit in the scan mask
- * @indio_dev: the iio device
- * @buffer: the buffer whose scan mask we are interested in
- * @bit: the bit to be set.
- *
- * Note that at this point we have no way of knowing what other
- * buffers might request, hence this code only verifies that the
- * individual buffers request is plausible.
- */
-int iio_scan_mask_set(struct iio_dev *indio_dev,
-		      struct iio_buffer *buffer, int bit)
+int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev)
 {
-	const unsigned long *mask;
-	unsigned long *trialmask;
+	struct iio_dev_attr *p;
+	struct attribute **attr;
+	struct iio_buffer *buffer = indio_dev->buffer;
+	int ret, i, attrn, attrcount, attrcount_orig = 0;
+	const struct iio_chan_spec *channels;
 
-	trialmask = kmalloc(sizeof(*trialmask)*
-			    BITS_TO_LONGS(indio_dev->masklength),
-			    GFP_KERNEL);
+	if (!buffer)
+		return 0;
 
-	if (trialmask == NULL)
+	attrcount = 0;
+	if (buffer->attrs) {
+		while (buffer->attrs[attrcount] != NULL)
+			attrcount++;
+	}
+
+	buffer->buffer_group.name = "buffer";
+	buffer->buffer_group.attrs = kcalloc(attrcount + 3,
+			sizeof(*buffer->buffer_group.attrs), GFP_KERNEL);
+	if (!buffer->buffer_group.attrs)
 		return -ENOMEM;
-	if (!indio_dev->masklength) {
-		WARN_ON("Trying to set scanmask prior to registering buffer\n");
-		goto err_invalid_mask;
+
+	if (buffer->access->set_length)
+		buffer->buffer_group.attrs[0] = &dev_attr_length.attr;
+	else
+		buffer->buffer_group.attrs[0] = &dev_attr_length_ro.attr;
+	buffer->buffer_group.attrs[1] = &dev_attr_enable.attr;
+	if (buffer->attrs)
+		memcpy(&buffer->buffer_group.attrs[2], buffer->attrs,
+			sizeof(*&buffer->buffer_group.attrs) * attrcount);
+	buffer->buffer_group.attrs[attrcount+2] = NULL;
+
+	indio_dev->groups[indio_dev->groupcounter++] = &buffer->buffer_group;
+
+	if (buffer->scan_el_attrs != NULL) {
+		attr = buffer->scan_el_attrs->attrs;
+		while (*attr++ != NULL)
+			attrcount_orig++;
 	}
-	bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength);
-	set_bit(bit, trialmask);
+	attrcount = attrcount_orig;
+	INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list);
+	channels = indio_dev->channels;
+	if (channels) {
+		/* new magic */
+		for (i = 0; i < indio_dev->num_channels; i++) {
+			if (channels[i].scan_index < 0)
+				continue;
 
-	if (!iio_validate_scan_mask(indio_dev, trialmask))
-		goto err_invalid_mask;
+			/* Establish necessary mask length */
+			if (channels[i].scan_index >
+			    (int)indio_dev->masklength - 1)
+				indio_dev->masklength
+					= channels[i].scan_index + 1;
 
-	if (indio_dev->available_scan_masks) {
-		mask = iio_scan_mask_match(indio_dev->available_scan_masks,
-					   indio_dev->masklength,
-					   trialmask);
-		if (!mask)
-			goto err_invalid_mask;
+			ret = iio_buffer_add_channel_sysfs(indio_dev,
+							 &channels[i]);
+			if (ret < 0)
+				goto error_cleanup_dynamic;
+			attrcount += ret;
+			if (channels[i].type == IIO_TIMESTAMP)
+				indio_dev->scan_index_timestamp =
+					channels[i].scan_index;
+		}
+		if (indio_dev->masklength && buffer->scan_mask == NULL) {
+			buffer->scan_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength),
+						    sizeof(*buffer->scan_mask),
+						    GFP_KERNEL);
+			if (buffer->scan_mask == NULL) {
+				ret = -ENOMEM;
+				goto error_cleanup_dynamic;
+			}
+		}
 	}
-	bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength);
 
-	kfree(trialmask);
+	buffer->scan_el_group.name = iio_scan_elements_group_name;
+
+	buffer->scan_el_group.attrs = kcalloc(attrcount + 1,
+					      sizeof(buffer->scan_el_group.attrs[0]),
+					      GFP_KERNEL);
+	if (buffer->scan_el_group.attrs == NULL) {
+		ret = -ENOMEM;
+		goto error_free_scan_mask;
+	}
+	if (buffer->scan_el_attrs)
+		memcpy(buffer->scan_el_group.attrs, buffer->scan_el_attrs,
+		       sizeof(buffer->scan_el_group.attrs[0])*attrcount_orig);
+	attrn = attrcount_orig;
+
+	list_for_each_entry(p, &buffer->scan_el_dev_attr_list, l)
+		buffer->scan_el_group.attrs[attrn++] = &p->dev_attr.attr;
+	indio_dev->groups[indio_dev->groupcounter++] = &buffer->scan_el_group;
 
 	return 0;
 
-err_invalid_mask:
-	kfree(trialmask);
-	return -EINVAL;
+error_free_scan_mask:
+	kfree(buffer->scan_mask);
+error_cleanup_dynamic:
+	iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list);
+	kfree(indio_dev->buffer->buffer_group.attrs);
+
+	return ret;
+}
+
+void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev)
+{
+	if (!indio_dev->buffer)
+		return;
+
+	kfree(indio_dev->buffer->scan_mask);
+	kfree(indio_dev->buffer->buffer_group.attrs);
+	kfree(indio_dev->buffer->scan_el_group.attrs);
+	iio_free_chan_devattr_list(&indio_dev->buffer->scan_el_dev_attr_list);
+}
+
+/**
+ * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected
+ * @indio_dev: the iio device
+ * @mask: scan mask to be checked
+ *
+ * Return true if exactly one bit is set in the scan mask, false otherwise. It
+ * can be used for devices where only one channel can be active for sampling at
+ * a time.
+ */
+bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev,
+	const unsigned long *mask)
+{
+	return bitmap_weight(mask, indio_dev->masklength) == 1;
 }
-EXPORT_SYMBOL_GPL(iio_scan_mask_set);
+EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot);
 
 int iio_scan_mask_query(struct iio_dev *indio_dev,
 			struct iio_buffer *buffer, int bit)