iio: add support for binary attributes

When a IIO device is registered, the IIO core creates an attribute group on
its own, where it puts the channel attributes, and where it copies the
attributes in indio_dev->info->attrs.

Unfortunately it doesn't take care of binary attributes (i.e. it only
consider indio_dev->info->attrs->attrs, and it ignores
indio_dev->info->attrs->bin_attrs).

Fix this by making the IIO layer take care also of the binary attributes.

Note that while it is necessary to copy the non-binary attributes because
the IIO layer needs more room to add the channels attribute, it should be
enough to assign the bin_attrs pointer to the binary attributes pointed by
indio_dev->info->attrs->bin_attrs.

Signed-off-by: Andrea Merello <andrea.merello@iit.it>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220907132205.28021-8-andrea.merello@iit.it
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 8f12993f87bea2042776f97537ec19655d3f12e2..151ff39933548c73b3362b89e230ad7bb30c807d 100644 (file)
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -1576,7 +1576,7 @@ static int iio_device_register_sysfs(struct iio_dev *indio_dev)
                ret = -ENOMEM;
                goto error_clear_attrs;
        }
-       /* Copy across original attributes */
+       /* Copy across original attributes, and point to original binary attributes */
        if (indio_dev->info->attrs) {
                memcpy(iio_dev_opaque->chan_attr_group.attrs,
                       indio_dev->info->attrs->attrs,
@@ -1584,6 +1584,8 @@ static int iio_device_register_sysfs(struct iio_dev *indio_dev)
                       *attrcount_orig);
                iio_dev_opaque->chan_attr_group.is_visible =
                        indio_dev->info->attrs->is_visible;
+               iio_dev_opaque->chan_attr_group.bin_attrs =
+                       indio_dev->info->attrs->bin_attrs;
        }
        attrn = attrcount_orig;
        /* Add all elements from the list. */