iio: buffer: split buffer sysfs creation to take buffer as primary arg

Currently the iio_buffer_{alloc,free}_sysfs_and_mask() take 'indio_dev' as
primary argument. This change splits the main logic into a private function
that takes an IIO buffer as primary argument.

That way, the functions can be extended to configure the sysfs for multiple
buffers.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200917125951.861-1-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index a7d7e5143ed25d41c6aedbf07d9042dc64edf5f0..a4f6bb96d4f42505027f98392b208465ed04e9fa 100644 (file)
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -1264,26 +1264,14 @@ static struct attribute *iio_buffer_attrs[] = {
        &dev_attr_data_available.attr,
 };
 
-int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev)
+static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer,
+                                            struct iio_dev *indio_dev)
 {
        struct iio_dev_attr *p;
        struct attribute **attr;
-       struct iio_buffer *buffer = indio_dev->buffer;
        int ret, i, attrn, attrcount;
        const struct iio_chan_spec *channels;
 
-       channels = indio_dev->channels;
-       if (channels) {
-               int ml = indio_dev->masklength;
-
-               for (i = 0; i < indio_dev->num_channels; i++)
-                       ml = max(ml, channels[i].scan_index + 1);
-               indio_dev->masklength = ml;
-       }
-
-       if (!buffer)
-               return 0;
-
        attrcount = 0;
        if (buffer->attrs) {
                while (buffer->attrs[attrcount] != NULL)
@@ -1367,19 +1355,45 @@ error_cleanup_dynamic:
        return ret;
 }
 
-void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev)
+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;
+
+       channels = indio_dev->channels;
+       if (channels) {
+               int ml = indio_dev->masklength;
+
+               for (i = 0; i < indio_dev->num_channels; i++)
+                       ml = max(ml, channels[i].scan_index + 1);
+               indio_dev->masklength = ml;
+       }
 
        if (!buffer)
-               return;
+               return 0;
+
+       return __iio_buffer_alloc_sysfs_and_mask(buffer, indio_dev);
+}
 
+static void __iio_buffer_free_sysfs_and_mask(struct iio_buffer *buffer)
+{
        bitmap_free(buffer->scan_mask);
        kfree(buffer->buffer_group.attrs);
        kfree(buffer->scan_el_group.attrs);
        iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list);
 }
 
+void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev)
+{
+       struct iio_buffer *buffer = indio_dev->buffer;
+
+       if (!buffer)
+               return;
+
+       __iio_buffer_free_sysfs_and_mask(buffer);
+}
+
 /**
  * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected
  * @indio_dev: the iio device