[MTD] driver model updates
Update driver model support in the MTD framework, so it fits
better into the current udev-based hotplug framework:
- Each mtd_info now has a device node. MTD drivers should set
the dev.parent field to point to the physical device, before
setting up partitions or otherwise declaring MTDs.
- Those device nodes always map to /sys/class/mtdX device nodes,
which no longer depend on MTD_CHARDEV.
- Those mtdX sysfs nodes have a "starter set" of attributes;
it's not yet sufficient to replace /proc/mtd.
- Enabling MTD_CHARDEV provides /sys/class/mtdXro/ nodes and the
/sys/class/mtd*/dev attributes (for udev, mdev, etc).
- Include a MODULE_ALIAS_CHARDEV_MAJOR macro. It'll work with
udev creating the /dev/mtd* nodes, not just a static rootfs.
So the sysfs structure is pretty much what you'd expect, except
that readonly chardev nodes are a bit quirky.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index 06d5b9d..02ce38f 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -356,6 +356,11 @@
slave->mtd.owner = master->owner;
slave->mtd.backing_dev_info = master->backing_dev_info;
+ /* NOTE: we don't arrange MTDs as a tree; it'd be error-prone
+ * to have the same data be in two different partitions.
+ */
+ slave->mtd.dev.parent = master->dev.parent;
+
slave->mtd.read = part_read;
slave->mtd.write = part_write;
@@ -508,7 +513,9 @@
* This function, given a master MTD object and a partition table, creates
* and registers slave MTD objects which are bound to the master according to
* the partition definitions.
- * (Q: should we register the master MTD object as well?)
+ *
+ * We don't register the master, or expect the caller to have done so,
+ * for reasons of data integrity.
*/
int add_mtd_partitions(struct mtd_info *master,