[PATCH v2 13/11] mtd: assign mtd->dev.of_node when creating partition devices

[Boris Brezillon]

MTD partitions may have been created from a DT definition, and in this case
the ->of_node of the struct device embedded in mtd_info should point to
the DT node that was used to create the partition.

Signed-off-by: Boris Brezillon <boris.brezillon at free-electrons.com>
---
Hi Brian,

Yet another patch that IMO should go into your "mtd: migrate 'of_node'
handling to core, not in mtd_part_parser_data" series.

Best Regards,

Boris

 drivers/mtd/mtdcore.c          | 17 +++++++++++++----
 drivers/mtd/mtdpart.c          |  3 +++
 drivers/mtd/ofpart.c           |  1 +
 include/linux/mtd/partitions.h |  1 +
 4 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index b1eea48..6101288 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -32,6 +32,7 @@
 #include <linux/err.h>
 #include <linux/ioctl.h>
 #include <linux/init.h>
+#include <linux/of.h>
 #include <linux/proc_fs.h>
 #include <linux/idr.h>
 #include <linux/backing-dev.h>
@@ -584,11 +585,13 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
 			      const struct mtd_partition *parts,
 			      int nr_parts)
 {
-	int ret;
+	int ret, i;
 	struct mtd_partition *real_parts = NULL;
 
 	ret = parse_mtd_partitions(mtd, types, &real_parts, parser_data);
-	if (ret <= 0 && nr_parts && parts) {
+	if (ret > 0) {
+		nr_parts = ret;
+	} else if (nr_parts && parts) {
 		real_parts = kmemdup(parts, sizeof(*parts) * nr_parts,
 				     GFP_KERNEL);
 		if (!real_parts)
@@ -604,7 +607,7 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
 		ret = 0;
 	}
 
-	ret = mtd_add_device_partitions(mtd, real_parts, ret);
+	ret = mtd_add_device_partitions(mtd, real_parts, nr_parts);
 	if (ret)
 		goto out;
 
@@ -623,7 +626,13 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
 	}
 
 out:
-	kfree(real_parts);
+	if (real_parts) {
+		for (i = 0; i < nr_parts; i++)
+			of_node_put(real_parts[i].of_node);
+
+		kfree(real_parts);
+	}
+
 	return ret;
 }
 EXPORT_SYMBOL_GPL(mtd_device_parse_register);
diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index f8ba153..95f3a0d 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -29,6 +29,7 @@
 #include <linux/kmod.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/partitions.h>
+#include <linux/of.h>
 #include <linux/err.h>
 #include <linux/kconfig.h>
 
@@ -319,6 +320,7 @@ static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
 
 static inline void free_partition(struct mtd_part *p)
 {
+	of_node_put(mtd_get_of_node(&p->mtd));
 	kfree(p->mtd.name);
 	kfree(p);
 }
@@ -391,6 +393,7 @@ static struct mtd_part *allocate_partition(struct mtd_info *master,
 	slave->mtd.dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) ?
 				&master->dev :
 				master->dev.parent;
+	mtd_set_of_node(&slave->mtd, of_node_get(part->of_node));
 
 	slave->mtd._read = part_read;
 	slave->mtd._write = part_write;
diff --git a/drivers/mtd/ofpart.c b/drivers/mtd/ofpart.c
index f78d2ae..5c64e04 100644
--- a/drivers/mtd/ofpart.c
+++ b/drivers/mtd/ofpart.c
@@ -111,6 +111,7 @@ static int parse_ofpart_partitions(struct mtd_info *master,
 		if (of_get_property(pp, "lock", &len))
 			(*pparts)[i].mask_flags |= MTD_POWERUP_LOCK;
 
+		(*pparts)[i].of_node = of_node_get(pp);
 		i++;
 	}
 
diff --git a/include/linux/mtd/partitions.h b/include/linux/mtd/partitions.h
index 773975a..282644c 100644
--- a/include/linux/mtd/partitions.h
+++ b/include/linux/mtd/partitions.h
@@ -42,6 +42,7 @@ struct mtd_partition {
 	uint64_t offset;		/* offset within the master MTD space */
 	uint32_t mask_flags;		/* master MTD flags to mask out for this partition */
 	struct nand_ecclayout *ecclayout;	/* out of band layout for this partition (NAND only) */
+	struct device_node *of_node;	/* OF node attached to the partition */
 };
 
 #define MTDPART_OFS_RETAIN	(-3)
-- 
2.1.4