dm: blk: Add a way to obtain a block device from its parent
Many devices support a child block device (e.g. MMC, USB). Add a
convenient way to get this device given the parent device.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/include/blk.h b/include/blk.h
index a128ee4..4d60987 100644
--- a/include/blk.h
+++ b/include/blk.h
@@ -616,4 +616,11 @@
*/
int blk_select_hwpart_devnum(enum if_type if_type, int devnum, int hwpart);
+/**
+ * blk_get_from_parent() - obtain a block device by looking up its parent
+ *
+ * All devices with
+ */
+int blk_get_from_parent(struct udevice *parent, struct udevice **devp);
+
#endif