From: Rafał Miłecki <[email protected]> MTD subsystem API allows interacting with MTD devices (e.g. reading, writing, handling bad blocks). So far a random driver could get MTD device only by its name (get_mtd_device_nm()). This change allows getting them also by a DT node.
This API is required for drivers handling DT defined MTD partitions in a specific way (e.g. U-Boot (sub)partition with environment variables). Signed-off-by: Rafał Miłecki <[email protected]> Acked-by: Miquel Raynal <[email protected]> --- V3: First introduction of of_get_mtd_device_by_node() V4: Use EPROBE_DEFER Srinivas: in V3 Miquel said it's OK to push this patch through NVMEM --- drivers/mtd/mtdcore.c | 28 ++++++++++++++++++++++++++++ include/linux/mtd/mtd.h | 1 + 2 files changed, 29 insertions(+) diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 9eb0680db312..3613cc142f25 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -1154,6 +1154,34 @@ int __get_mtd_device(struct mtd_info *mtd) } EXPORT_SYMBOL_GPL(__get_mtd_device); +/** + * of_get_mtd_device_by_node - obtain an MTD device associated with a given node + * + * @np: device tree node + */ +struct mtd_info *of_get_mtd_device_by_node(struct device_node *np) +{ + struct mtd_info *mtd = NULL; + struct mtd_info *tmp; + int err; + + mutex_lock(&mtd_table_mutex); + + err = -EPROBE_DEFER; + mtd_for_each_device(tmp) { + if (mtd_get_of_node(tmp) == np) { + mtd = tmp; + err = __get_mtd_device(mtd); + break; + } + } + + mutex_unlock(&mtd_table_mutex); + + return err ? ERR_PTR(err) : mtd; +} +EXPORT_SYMBOL_GPL(of_get_mtd_device_by_node); + /** * get_mtd_device_nm - obtain a validated handle for an MTD device by * device name diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h index 955aee14b0f7..6fc841ceef31 100644 --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -677,6 +677,7 @@ 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); extern void __put_mtd_device(struct mtd_info *mtd); +extern struct mtd_info *of_get_mtd_device_by_node(struct device_node *np); extern struct mtd_info *get_mtd_device_nm(const char *name); extern void put_mtd_device(struct mtd_info *mtd); -- 2.34.1
