Mention that this function is also used with a NULL block devices to
access files on the host, when using sandbox.
Update the comment on struct bootflow also.
Signed-off-by: Simon Glass <sjg@chromium.org>
* @glob_node: Points to siblings in the global list (all bootdev)
* @dev: Bootdevice device which produced this bootflow
* @blk: Block device which contains this bootflow, NULL if this is a network
- * device
+ * device or sandbox 'host' device
* @part: Partition number (0 for whole device)
* @fs_type: Filesystem type (FS_TYPE...) if this is fixed by the media, else 0.
* For example, the sandbox host-filesystem bootdev sets this to
* caller before reading the file.
*
* @bflow: Information about file to try
- * @desc: Block descriptor to read from
+ * @desc: Block descriptor to read from (NULL for sandbox host)
* @prefix: Filename prefix to prepend to @fname (NULL for none)
* @fname: Filename to read
* Return: 0 if OK, -ENOMEM if not enough memory to allocate bflow->fname,