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>
This commit is contained in:
Dmitry Eremin-Solenikov 2011-03-25 22:26:25 +03:00 committed by Artem Bityutskiy
parent 3761a6ddac
commit 1c4c215cbd
2 changed files with 63 additions and 0 deletions

View File

@ -451,6 +451,64 @@ int mtd_device_register(struct mtd_info *master,
}
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.
*

View File

@ -327,6 +327,11 @@ struct mtd_partition;
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);