staging:iio: rework of attribute registration.

[deliverable/linux.git] / drivers / staging / iio / industrialio-ring.c

diff --git a/drivers/staging/iio/industrialio-ring.c b/drivers/staging/iio/industrialio-ring.c
index 6f14c0d848677ce21edb3ba67a6200df9ac3652d..7a95fbe0eedc0e0707274ad6298bf2e3f3761554 100644 (file)
--- a/drivers/staging/iio/industrialio-ring.c
+++ b/drivers/staging/iio/industrialio-ring.c
@@ -207,10 +207,10 @@ error_ret:
 static int iio_ring_add_channel_sysfs(struct iio_dev *indio_dev,
                                      const struct iio_chan_spec *chan)
 {
-       int ret;
+       int ret, attrcount = 0;
        struct iio_ring_buffer *ring = indio_dev->ring;
 
-       ret = __iio_add_chan_devattr("index", "scan_elements",
+       ret = __iio_add_chan_devattr("index",
                                     chan,
                                     &iio_show_scan_index,
                                     NULL,
@@ -220,8 +220,8 @@ static int iio_ring_add_channel_sysfs(struct iio_dev *indio_dev,
                                     &ring->scan_el_dev_attr_list);
        if (ret)
                goto error_ret;
-
-       ret = __iio_add_chan_devattr("type", "scan_elements",
+       attrcount++;
+       ret = __iio_add_chan_devattr("type",
                                     chan,
                                     &iio_show_fixed_type,
                                     NULL,
@@ -231,9 +231,9 @@ static int iio_ring_add_channel_sysfs(struct iio_dev *indio_dev,
                                     &ring->scan_el_dev_attr_list);
        if (ret)
                goto error_ret;
-
+       attrcount++;
        if (chan->type != IIO_TIMESTAMP)
-               ret = __iio_add_chan_devattr("en", "scan_elements",
+               ret = __iio_add_chan_devattr("en",
                                             chan,
                                             &iio_scan_el_show,
                                             &iio_scan_el_store,
@@ -242,7 +242,7 @@ static int iio_ring_add_channel_sysfs(struct iio_dev *indio_dev,
                                             &indio_dev->dev,
                                             &ring->scan_el_dev_attr_list);
        else
-               ret = __iio_add_chan_devattr("en", "scan_elements",
+               ret = __iio_add_chan_devattr("en",
                                             chan,
                                             &iio_scan_el_ts_show,
                                             &iio_scan_el_ts_store,
@@ -250,6 +250,8 @@ static int iio_ring_add_channel_sysfs(struct iio_dev *indio_dev,
                                             0,
                                             &indio_dev->dev,
                                             &ring->scan_el_dev_attr_list);
+       attrcount++;
+       ret = attrcount;
 error_ret:
        return ret;
 }
@@ -257,66 +259,40 @@ error_ret:
 static void iio_ring_remove_and_free_scan_dev_attr(struct iio_dev *indio_dev,
                                                   struct iio_dev_attr *p)
 {
-       sysfs_remove_file_from_group(&indio_dev->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_dev *indio_dev)
 {
        struct iio_dev_attr *p, *n;
        struct iio_ring_buffer *ring = indio_dev->ring;
-       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(indio_dev, p);
-
-       if (ring->scan_el_attrs)
-               sysfs_remove_group(&indio_dev->dev.kobj,
-                                  ring->scan_el_attrs);
-       else if (anydynamic)
-               sysfs_remove_group(&indio_dev->dev.kobj,
-                                  &iio_scan_el_dummy_group);
 }
 
+static const char * const iio_scan_elements_group_name = "scan_elements";
+
 int iio_ring_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_ring_buffer *ring = indio_dev->ring;
-       int ret, i;
-
-       if (ring->scan_el_attrs) {
-               ret = sysfs_create_group(&indio_dev->dev.kobj,
-                                        ring->scan_el_attrs);
-               if (ret) {
-                       dev_err(&indio_dev->dev,
-                               "Failed to add sysfs scan elements\n");
-                       goto error_ret;
-               }
-       } else if (channels) {
-               ret = sysfs_create_group(&indio_dev->dev.kobj,
-                                        &iio_scan_el_dummy_group);
-               if (ret)
-                       goto error_ret;
-       }
-       if (ring->attrs) {
-               ret = sysfs_create_group(&indio_dev->dev.kobj,
-                                        ring->attrs);
-               if (ret)
-                       goto error_cleanup_dynamic;
-       }
+       int ret, i, attrn, attrcount, attrcount_orig = 0;
+
+       if (ring->attrs)
+               indio_dev->groups[indio_dev->groupcounter++] = ring->attrs;
 
+       if (ring->scan_el_attrs != NULL) {
+               attr = ring->scan_el_attrs->attrs;
+               while (*attr++ != NULL)
+                       attrcount_orig++;
+       }
+       attrcount = attrcount_orig;
        INIT_LIST_HEAD(&ring->scan_el_dev_attr_list);
        if (channels) {
                /* new magic */
@@ -330,7 +306,8 @@ int iio_ring_buffer_register(struct iio_dev *indio_dev,
                        ret = iio_ring_add_channel_sysfs(indio_dev,
                                                         &channels[i]);
                        if (ret < 0)
-                               goto error_cleanup_group;
+                               goto error_cleanup_dynamic;
+                       attrcount += ret;
                }
                if (indio_dev->masklength && ring->scan_mask == NULL) {
                        ring->scan_mask
@@ -339,18 +316,36 @@ int iio_ring_buffer_register(struct iio_dev *indio_dev,
                                          GFP_KERNEL);
                        if (ring->scan_mask == NULL) {
                                ret = -ENOMEM;
-                               goto error_cleanup_group;
+                               goto error_cleanup_dynamic;
                        }
                }
        }
 
+       ring->scan_el_group.name = iio_scan_elements_group_name;
+
+       ring->scan_el_group.attrs
+               = kzalloc(sizeof(ring->scan_el_group.attrs[0])*(attrcount + 1),
+                         GFP_KERNEL);
+       if (ring->scan_el_group.attrs == NULL) {
+               ret = -ENOMEM;
+               goto error_free_scan_mask;
+       }
+       if (ring->scan_el_attrs)
+               memcpy(ring->scan_el_group.attrs, ring->scan_el_attrs,
+                      sizeof(ring->scan_el_group.attrs[0])*attrcount_orig);
+       attrn = attrcount_orig;
+
+       list_for_each_entry(p, &ring->scan_el_dev_attr_list, l)
+               ring->scan_el_group.attrs[attrn++] = &p->dev_attr.attr;
+       indio_dev->groups[indio_dev->groupcounter++] = &ring->scan_el_group;
+
        return 0;
-error_cleanup_group:
-       if (ring->attrs)
-               sysfs_remove_group(&indio_dev->dev.kobj, ring->attrs);
+
+error_free_scan_mask:
+       kfree(ring->scan_mask);
 error_cleanup_dynamic:
        __iio_ring_attr_cleanup(indio_dev);
-error_ret:
+
        return ret;
 }
 EXPORT_SYMBOL(iio_ring_buffer_register);
@@ -358,9 +353,7 @@ EXPORT_SYMBOL(iio_ring_buffer_register);
 void iio_ring_buffer_unregister(struct iio_dev *indio_dev)
 {
        kfree(indio_dev->ring->scan_mask);
-       if (indio_dev->ring->attrs)
-               sysfs_remove_group(&indio_dev->dev.kobj,
-                                  indio_dev->ring->attrs);
+       kfree(indio_dev->ring->scan_el_group.attrs);
        __iio_ring_attr_cleanup(indio_dev);
 }
 EXPORT_SYMBOL(iio_ring_buffer_unregister);