[PATCH v2] mtd: unify mtd partition/device registration

[Mike Frysinger <vapier@gentoo.org>]

Rather than having every map/mtd driver doing the same sequence of
registering partitions and/or devices, implement common parse_mtd().

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
---
v2:
	- ifdef parsers in parse_mtd()
	- add "always_whole" to parse_mtd()
	- add unparse_mtd()

 drivers/mtd/mtdcore.c   |   60 +++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/mtd/mtd.h |    5 ++++
 2 files changed, 65 insertions(+), 0 deletions(-)

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index a9d2469..2e91785 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -292,6 +292,66 @@ void put_mtd_device(struct mtd_info *mtd)
 	module_put(mtd->owner);
 }
 
+#include <linux/mtd/partitions.h>
+
+/**
+ *	parse_mtd - add partitions / devices
+ *
+ *	If partitioning support is enabled, attempt to call parse_mtd_partitions()
+ *	and add_mtd_partitions() with all available parsers.  Otherwise just add
+ *	the MTD device.
+ */
+
+int parse_mtd(struct mtd_info *mtd, const char **probe_types,
+              struct mtd_partition *parts, int nr_parts, bool always_whole)
+{
+	int ret;
+#ifdef CONFIG_MTD_PARTITIONS
+	const char *default_part_probe_types[] = {
+# ifdef CONFIG_MTD_CMDLINE_PARTS
+		"cmdlinepart",
+# endif
+# ifdef CONFIG_MTD_REDBOOT_PARTS
+		"RedBoot",
+# endif
+		NULL
+	};
+
+	if (!probe_types)
+		probe_types = default_part_probe_types;
+
+	ret = parse_mtd_partitions(mtd, probe_types, &parts, 0);
+	if (ret > 0) {
+		ret = add_mtd_partitions(mtd, parts, ret);
+		kfree(parts);
+	} else if (nr_parts)
+		ret = add_mtd_partitions(mtd, parts, nr_parts);
+#else
+	always_whole = true;
+#endif
+
+	if (always_whole)
+		ret = add_mtd_device(mtd);
+
+	return ret;
+}
+EXPORT_SYMBOL(parse_mtd);
+
+/**
+ *	unparse_mtd - remove partitions / devices
+ *
+ *	Undo the parse_mtd() steps -- so unregister all partitions and devices.
+ */
+
+void unparse_mtd(struct mtd_info *mtd)
+{
+#ifdef CONFIG_MTD_PARTITIONS
+	del_mtd_partitions(mtd);
+#endif
+	del_mtd_device(mtd);
+}
+EXPORT_SYMBOL(unparse_mtd);
+
 /* default_mtd_writev - default mtd writev method for MTD devices that
  *			don't implement their own
  */
diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
index eae26bb..68ceaab 100644
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -232,6 +232,11 @@ extern struct mtd_info *get_mtd_device_nm(const char *name);
 
 extern void put_mtd_device(struct mtd_info *mtd);
 
+struct mtd_partition;
+extern int parse_mtd(struct mtd_info *mtd, const char **probe_types,
+                     struct mtd_partition *parts, int nr_parts,
+                     bool always_whole);
+extern void unparse_mtd(struct mtd_info *mtd);
 
 struct mtd_notifier {
 	void (*add)(struct mtd_info *mtd);
-- 
1.6.0.3