mtd: add new API for handling MTD registration
Lots (nearly all) mtd drivers contain nearly the similar code that
calls parse_mtd_partitions, provides some platform-default values, if
parsing fails, and registers mtd device.
This is an aim to provide single implementation of this scenario:
mtd_device_parse_register() which will handle all this parsing and
defaults.
Artem: amended comments
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index c510aff..1326747 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -452,6 +452,64 @@
EXPORT_SYMBOL_GPL(mtd_device_register);
/**
+ * mtd_device_parse_register - parse partitions and register an MTD device.
+ *
+ * @mtd: the MTD device to register
+ * @types: the list of MTD partition probes to try, see
+ * 'parse_mtd_partitions()' for more information
+ * @origin: start address of MTD device, %0 unless you are sure you need this.
+ * @parts: fallback partition information to register, if parsing fails;
+ * only valid if %nr_parts > %0
+ * @nr_parts: the number of partitions in parts, if zero then the full
+ * MTD device is registered if no partition info is found
+ *
+ * This function aggregates MTD partitions parsing (done by
+ * 'parse_mtd_partitions()') and MTD device and partitions registering. It
+ * basically follows the most common pattern found in many MTD drivers:
+ *
+ * * It first tries to probe partitions on MTD device @mtd using parsers
+ * specified in @types (if @types is %NULL, then the default list of parsers
+ * is used, see 'parse_mtd_partitions()' for more information). If none are
+ * found this functions tries to fallback to information specified in
+ * @parts/@nr_parts.
+ * * If any parititioning info was found, this function registers the found
+ * partitions.
+ * * If no partitions were found this function just registers the MTD device
+ * @mtd and exits.
+ *
+ * Returns zero in case of success and a negative error code in case of failure.
+ */
+int mtd_device_parse_register(struct mtd_info *mtd, const char **types,
+ unsigned long origin,
+ const struct mtd_partition *parts,
+ int nr_parts)
+{
+ int err;
+ struct mtd_partition *real_parts;
+
+ err = parse_mtd_partitions(mtd, types, &real_parts, origin);
+ if (err <= 0 && nr_parts) {
+ real_parts = kmemdup(parts, sizeof(*parts) * nr_parts,
+ GFP_KERNEL);
+ err = nr_parts;
+ if (!parts)
+ err = -ENOMEM;
+ }
+
+ if (err > 0) {
+ err = add_mtd_partitions(mtd, real_parts, err);
+ kfree(real_parts);
+ } else if (err == 0) {
+ err = add_mtd_device(mtd);
+ if (err == 1)
+ err = -ENODEV;
+ }
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(mtd_device_parse_register);
+
+/**
* mtd_device_unregister - unregister an existing MTD device.
*
* @master: the MTD device to unregister. This will unregister both the master
diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
index 2541fb8..d28a241 100644
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -327,6 +327,11 @@
extern int mtd_device_register(struct mtd_info *master,
const struct mtd_partition *parts,
int nr_parts);
+extern int mtd_device_parse_register(struct mtd_info *mtd,
+ const char **part_probe_types,
+ unsigned long origin,
+ const struct mtd_partition *defparts,
+ int defnr_parts);
extern int mtd_device_unregister(struct mtd_info *master);
extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
extern int __get_mtd_device(struct mtd_info *mtd);