mtd: introduce mtd_erase interface

This patch is part of a patch-set which changes the MTD interface
from 'mtd->func()' form to 'mtd_func()' form. We need this because
we want to add common code to to all drivers in the mtd core level,
which is impossible with the current interface when MTD clients
call driver functions like 'read()' or 'write()' directly.

At this point we just introduce a new inline wrapper function, but
later some of them are expected to gain more code. E.g., the input
parameters check should be moved to the wrappers rather than be
duplicated at many drivers.

This particular patch introduced the 'mtd_erase()' interface. The
following patches add all the other interfaces one by one.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 14 insertions, 5 deletions

diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
index 9f5b312af78..201bad55704 100644
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -171,11 +171,8 @@ struct mtd_info {
 	struct mtd_erase_region_info *eraseregions;
 
 	/*
-	 * Erase is an asynchronous operation.  Device drivers are supposed
-	 * to call instr->callback() whenever the operation completes, even
-	 * if it completes with a failure.
-	 * Callers are supposed to pass a callback function and wait for it
-	 * to be called before writing to the block.
+	 * Do not call via these pointers, use corresponding mtd_*()
+	 * wrappers instead.
 	 */
 	int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
 
@@ -274,6 +271,18 @@ struct mtd_info {
 	void (*put_device) (struct mtd_info *mtd);
 };
 
+/*
+ * Erase is an asynchronous operation.  Device drivers are supposed
+ * to call instr->callback() whenever the operation completes, even
+ * if it completes with a failure.
+ * Callers are supposed to pass a callback function and wait for it
+ * to be called before writing to the block.
+ */
+static inline int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
+{
+	return mtd->erase(mtd, instr);
+}
+
 static inline struct mtd_info *dev_to_mtd(struct device *dev)
 {
 	return dev ? dev_get_drvdata(dev) : NULL;