mtd: ubi: populate ubi volume fwnode

Look for the 'volumes' subnode of an MTD partition attached to a UBI
device and attach matching child nodes to UBI volumes.
This allows UBI volumes to be referenced in device tree, e.g. for use
as NVMEM providers.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Signed-off-by: Richard Weinberger <richard@nod.at>

diff --git a/drivers/mtd/ubi/vmt.c b/drivers/mtd/ubi/vmt.c
index eaf8328f6fc38715998df35d49c6a2c307bccb86..5a3558bbb90356f0e1394b9b882b8992e4c8d019 100644 (file)
--- a/drivers/mtd/ubi/vmt.c
+++ b/drivers/mtd/ubi/vmt.c
@@ -124,6 +124,31 @@ static void vol_release(struct device *dev)
        kfree(vol);
 }
 
+static struct fwnode_handle *find_volume_fwnode(struct ubi_volume *vol)
+{
+       struct fwnode_handle *fw_vols, *fw_vol;
+       const char *volname;
+       u32 volid;
+
+       fw_vols = device_get_named_child_node(vol->dev.parent->parent, "volumes");
+       if (!fw_vols)
+               return NULL;
+
+       fwnode_for_each_child_node(fw_vols, fw_vol) {
+               if (!fwnode_property_read_string(fw_vol, "volname", &volname) &&
+                   strncmp(volname, vol->name, vol->name_len))
+                       continue;
+
+               if (!fwnode_property_read_u32(fw_vol, "volid", &volid) &&
+                   vol->vol_id != volid)
+                       continue;
+
+               return fw_vol;
+       }
+
+       return NULL;
+}
+
 /**
  * ubi_create_volume - create volume.
  * @ubi: UBI device description object
@@ -223,6 +248,7 @@ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req)
        vol->name_len  = req->name_len;
        memcpy(vol->name, req->name, vol->name_len);
        vol->ubi = ubi;
+       device_set_node(&vol->dev, find_volume_fwnode(vol));
 
        /*
         * Finish all pending erases because there may be some LEBs belonging
@@ -614,6 +640,7 @@ int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol)
        vol->dev.class = &ubi_class;
        vol->dev.groups = volume_dev_groups;
        dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
+       device_set_node(&vol->dev, find_volume_fwnode(vol));
        err = device_register(&vol->dev);
        if (err) {
                cdev_del(&vol->cdev);