[PATCH v2 04/12] iio: buffer: add index to the first IIO buffer dir and symlink it back

[Alexandru Ardelean]

This change makes it so that the first buffer directory is named 'buffer0'
and moves the 'scan_elements' under it.

For backwards compatibility these folders are symlinked back to the
original folders.

Signed-off-by: Alexandru Ardelean <alexandru.ardel...@analog.com>
---
 drivers/iio/industrialio-buffer.c | 66 +++++++++++++++++++++----------
 1 file changed, 46 insertions(+), 20 deletions(-)

diff --git a/drivers/iio/industrialio-buffer.c 
b/drivers/iio/industrialio-buffer.c
index 0f470d902790..628d78125126 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -1369,7 +1369,8 @@ static void iio_sysfs_del_attrs(struct kobject *kobj, 
struct attribute **ptr)
  * IIO device.
  */
 static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer,
-                                            struct iio_dev *indio_dev)
+                                            struct iio_dev *indio_dev,
+                                            unsigned int idx)
 {
        struct iio_dev_attr *p;
        struct attribute **attr;
@@ -1401,7 +1402,7 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct 
iio_buffer *buffer,
        buffer->buffer_attrs = attr;
 
        ret = kobject_init_and_add(&buffer->buffer_dir, &iio_buffer_dir_ktype,
-                                  &indio_dev->dev.kobj, "buffer");
+                                  &indio_dev->dev.kobj, "buffer%u", idx);
        if (ret)
                goto error_buffer_free_attrs;
 
@@ -1446,7 +1447,7 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct 
iio_buffer *buffer,
        }
 
        ret = kobject_init_and_add(&buffer->scan_el_dir, &iio_scan_el_dir_ktype,
-                                  &indio_dev->dev.kobj, "scan_elements");
+                                  &buffer->buffer_dir, "scan_elements");
        if (ret)
                goto error_free_scan_attrs;
 
@@ -1477,6 +1478,22 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct 
iio_buffer *buffer,
        return ret;
 }
 
+/**
+ * __iio_buffer_free_sysfs_and_mask() - Free sysfs objects for a single IIO 
buffer
+ * @buffer: the iio buffer for which to destroy the objects
+ */
+static void __iio_buffer_free_sysfs_and_mask(struct iio_buffer *buffer)
+{
+       iio_sysfs_del_attrs(&buffer->scan_el_dir, buffer->scan_el_attrs);
+       kobject_put(&buffer->scan_el_dir);
+       kfree(buffer->scan_el_attrs);
+       bitmap_free(buffer->scan_mask);
+       iio_sysfs_del_attrs(&buffer->buffer_dir, buffer->buffer_attrs);
+       iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list);
+       kobject_put(&buffer->buffer_dir);
+       kfree(buffer->buffer_attrs);
+}
+
 /**
  * iio_buffer_alloc_sysfs_and_mask() - Allocate sysfs attributes to attached 
buffers
  * @indio_dev: the iio device for which to create the buffer sysfs attributes
@@ -1492,7 +1509,7 @@ int iio_buffer_alloc_sysfs_and_mask(struct iio_dev 
*indio_dev)
 {
        struct iio_buffer *buffer = indio_dev->buffer;
        const struct iio_chan_spec *channels;
-       int i;
+       int i, ret;
 
        channels = indio_dev->channels;
        if (channels) {
@@ -1506,23 +1523,29 @@ int iio_buffer_alloc_sysfs_and_mask(struct iio_dev 
*indio_dev)
        if (!buffer)
                return 0;
 
-       return __iio_buffer_alloc_sysfs_and_mask(buffer, indio_dev);
-}
+       ret = __iio_buffer_alloc_sysfs_and_mask(buffer, indio_dev, 0);
+       if (ret)
+               return ret;
 
-/**
- * __iio_buffer_free_sysfs_and_mask() - Free sysfs objects for a single IIO 
buffer
- * @buffer: the iio buffer for which to destroy the objects
- */
-static void __iio_buffer_free_sysfs_and_mask(struct iio_buffer *buffer)
-{
-       iio_sysfs_del_attrs(&buffer->scan_el_dir, buffer->scan_el_attrs);
-       kobject_put(&buffer->scan_el_dir);
-       kfree(buffer->scan_el_attrs);
-       bitmap_free(buffer->scan_mask);
-       iio_sysfs_del_attrs(&buffer->buffer_dir, buffer->buffer_attrs);
-       iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list);
-       kobject_put(&buffer->buffer_dir);
-       kfree(buffer->buffer_attrs);
+       ret = sysfs_create_link(&indio_dev->dev.kobj,
+                               &indio_dev->buffer->buffer_dir,
+                               "buffer");
+       if (ret)
+               goto error_free_sysfs_and_mask;
+
+       ret = sysfs_create_link(&indio_dev->dev.kobj,
+                               &indio_dev->buffer->scan_el_dir,
+                               "scan_elements");
+       if (ret)
+               goto error_remove_buffer_dir_link;
+
+       return 0;
+
+error_remove_buffer_dir_link:
+       sysfs_remove_link(&indio_dev->dev.kobj, "buffer");
+error_free_sysfs_and_mask:
+       __iio_buffer_free_sysfs_and_mask(buffer);
+       return ret;
 }
 
 /**
@@ -1538,6 +1561,9 @@ void iio_buffer_free_sysfs_and_mask(struct iio_dev 
*indio_dev)
        if (!buffer)
                return;
 
+       sysfs_remove_link(&indio_dev->dev.kobj, "scan_elements");
+       sysfs_remove_link(&indio_dev->dev.kobj, "buffer");
+
        __iio_buffer_free_sysfs_and_mask(buffer);
 }
 
-- 
2.17.1