mtd: nand: Update to Linux-5.9

This updates the barebox NAND layer and parts of the mtd layer to
Linux-5.9.

This patch is huge, but the barebox NAND layer is so far away from the
Linux NAND layer that a step by step update would have taken ages.

Unlike Linux barebox has functions to mark a block as good. This feature
has been preserved. Also barebox used to make NAND write support
optional, this feature is lost during the update for the sake of better
compatibility to the Linux NAND layer.

This patch has been tested:

- GPMI aka nand_mxs on i.MX6
- nand_imx on i.MX25
- nand_omap_gpmc on AM335x
- atmel_nand on Atmel sama5d3
- nand_denali on SoCFPGA

Currently untested:

- nand_orion
- nand_mrvl_nfc
- nand_s3c24xx

The nand_denali driver is tested with the update of that driver to
Linux-5.9 following in the next patch.

I could only test the drivers with the NAND chips found on my boards, so
there's still enough room for regressions, especially given that the
NAND drivers themselves are mostly not updated. With the NAND layer
being up-to-date with Linux it should hopefully be easy to update
drivers to their Linux counterpart as well if necessary.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 538 insertions, 29 deletions

diff --git a/drivers/mtd/core.c b/drivers/mtd/core.c
index 8d018fde57..0e77bb69ec 100644
--- a/drivers/mtd/core.c
+++ b/drivers/mtd/core.c
@@ -15,6 +15,7 @@
 #include <common.h>
 #include <linux/mtd/nand.h>
 #include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
 #include <mtd/mtd-peb.h>
 #include <mtd/ubi-user.h>
 #include <cmdlinepart.h>
@@ -252,9 +253,7 @@ int mtd_ioctl(struct cdev *cdev, int request, void *buf)
 	int ret = 0;
 	struct mtd_info *mtd = cdev->priv;
 	struct mtd_info_user *user = buf;
-#if (defined(CONFIG_NAND_ECC_HW) || defined(CONFIG_NAND_ECC_SOFT))
 	struct mtd_ecc_stats *ecc = buf;
-#endif
 	struct region_info_user *reg = buf;
 #ifdef CONFIG_MTD_WRITE
 	struct erase_info_user *ei = buf;
@@ -292,14 +291,12 @@ int mtd_ioctl(struct cdev *cdev, int request, void *buf)
 		user->ecctype	= -1;
 		user->eccsize	= 0;
 		break;
-#if (defined(CONFIG_NAND_ECC_HW) || defined(CONFIG_NAND_ECC_SOFT))
 	case ECCGETSTATS:
 		ecc->corrected = mtd->ecc_stats.corrected;
 		ecc->failed = mtd->ecc_stats.failed;
 		ecc->badblocks = mtd->ecc_stats.badblocks;
 		ecc->bbtblocks = mtd->ecc_stats.bbtblocks;
 		break;
-#endif
 	case MEMGETREGIONINFO:
 		if (cdev->mtd) {
 			unsigned long size = cdev->size;
@@ -377,42 +374,66 @@ int mtd_block_markgood(struct mtd_info *mtd, loff_t ofs)
 }
 
 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
-		u_char *buf)
+             u_char *buf)
 {
-	int ret_code;
-	*retlen = 0;
+	struct mtd_oob_ops ops = {
+		.len = len,
+		.datbuf = buf,
+	};
+	int ret;
 
 	if (from < 0 || from >= mtd->size || len > mtd->size - from)
 		return -EINVAL;
 	if (!len)
 		return 0;
 
-	/*
-	 * In the absence of an error, drivers return a non-negative integer
-	 * representing the maximum number of bitflips that were corrected on
-	 * any one ecc region (if applicable; zero otherwise).
-	 */
-	ret_code = mtd->_read(mtd, from, len, retlen, buf);
-	if (unlikely(ret_code < 0))
-		return ret_code;
-	if (mtd->ecc_strength == 0)
-		return 0;	/* device lacks ecc */
-	return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
+	ret = mtd_read_oob(mtd, from, &ops);
+	*retlen = ops.retlen;
+
+	return ret;
+}
+
+int mtd_write_oob(struct mtd_info *mtd, loff_t to,
+				struct mtd_oob_ops *ops)
+{
+	int ret;
+
+	ops->retlen = ops->oobretlen = 0;
+
+	if (!(mtd->flags & MTD_WRITEABLE))
+		return -EROFS;
+
+	/* Check the validity of a potential fallback on mtd->_write */
+	if (!mtd->_write_oob && (!mtd->_write || ops->oobbuf))
+		return -EOPNOTSUPP;
+
+	if (mtd->_write_oob)
+		ret = mtd->_write_oob(mtd, to, ops);
+	else
+		ret = mtd->_write(mtd, to, ops->len, &ops->retlen,
+				     ops->datbuf);
+
+	return ret;
 }
 
 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
-		const u_char *buf)
+              const u_char *buf)
 {
-	*retlen = 0;
+        struct mtd_oob_ops ops = {
+                .len = len,
+                .datbuf = (u8 *)buf,
+        };
+        int ret;
 
 	if (to < 0 || to >= mtd->size || len > mtd->size - to)
 		return -EINVAL;
-	if (!mtd->_write || !(mtd->flags & MTD_WRITEABLE))
-		return -EROFS;
 	if (!len)
 		return 0;
 
-	return mtd->_write(mtd, to, len, retlen, buf);
+        ret = mtd_write_oob(mtd, to, &ops);
+        *retlen = ops.retlen;
+
+        return ret;
 }
 
 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
@@ -433,15 +454,23 @@ int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops)
 	int ret_code;
 
 	ops->retlen = ops->oobretlen = 0;
-	if (!mtd->_read_oob)
+
+	/* Check the validity of a potential fallback on mtd->_read */
+	if (!mtd->_read_oob && (!mtd->_read || ops->oobbuf))
 		return -EOPNOTSUPP;
+
 	/*
 	 * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics
 	 * similar to mtd->_read(), returning a non-negative integer
 	 * representing max bitflips. In other cases, mtd->_read_oob() may
 	 * return -EUCLEAN. In all cases, perform similar logic to mtd_read().
 	 */
-	ret_code = mtd->_read_oob(mtd, from, ops);
+	if (mtd->_read_oob)
+		ret_code = mtd->_read_oob(mtd, from, ops);
+	else
+		ret_code = mtd->_read(mtd, from, ops->len, &ops->retlen,
+				    ops->datbuf);
+
 	if (unlikely(ret_code < 0))
 		return ret_code;
 	if (mtd->ecc_strength == 0)
@@ -671,11 +700,13 @@ int add_mtd_device(struct mtd_info *mtd, const char *devname, int device_id)
 	if (mtd_can_have_bb(mtd))
 		mtd->cdev_bb = mtd_add_bb(mtd, NULL);
 
-	if (mtd->dev.parent && !mtd->parent) {
+	if (!mtd->parent) {
+		struct device_node *np = mtd_get_of_node(mtd);
+
 		dev_add_param_string(&mtd->dev, "partitions", mtd_partition_set, mtd_partition_get, &mtd->partition_string, mtd);
-		of_parse_partitions(&mtd->cdev, mtd->dev.parent->device_node);
-		if (IS_ENABLED(CONFIG_OFDEVICE) && mtd->dev.parent->device_node) {
-			mtd->of_path = xstrdup(mtd->dev.parent->device_node->full_name);
+		if (IS_ENABLED(CONFIG_OFDEVICE) && np) {
+			of_parse_partitions(&mtd->cdev, np);
+			mtd->of_path = xstrdup(np->full_name);
 			ret = of_partitions_register_fixup(&mtd->cdev);
 			if (ret)
 				goto err1;
@@ -742,3 +773,481 @@ const char *mtd_type_str(struct mtd_info *mtd)
 		return "unknown";
 	}
 }
+
+/**
+ * mtd_ooblayout_ecc - Get the OOB region definition of a specific ECC section
+ * @mtd: MTD device structure
+ * @section: ECC section. Depending on the layout you may have all the ECC
+ *	     bytes stored in a single contiguous section, or one section
+ *	     per ECC chunk (and sometime several sections for a single ECC
+ *	     ECC chunk)
+ * @oobecc: OOB region struct filled with the appropriate ECC position
+ *	    information
+ *
+ * This function returns ECC section information in the OOB area. If you want
+ * to get all the ECC bytes information, then you should call
+ * mtd_ooblayout_ecc(mtd, section++, oobecc) until it returns -ERANGE.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
+		      struct mtd_oob_region *oobecc)
+{
+	memset(oobecc, 0, sizeof(*oobecc));
+
+	if (section < 0)
+		return -EINVAL;
+
+	if (!mtd->ooblayout || !mtd->ooblayout->ecc)
+		return -ENOTSUPP;
+
+	return mtd->ooblayout->ecc(mtd, section, oobecc);
+}
+EXPORT_SYMBOL_GPL(mtd_ooblayout_ecc);
+
+/**
+ * mtd_ooblayout_free - Get the OOB region definition of a specific free
+ *			section
+ * @mtd: MTD device structure
+ * @section: Free section you are interested in. Depending on the layout
+ *	     you may have all the free bytes stored in a single contiguous
+ *	     section, or one section per ECC chunk plus an extra section
+ *	     for the remaining bytes (or other funky layout).
+ * @oobfree: OOB region struct filled with the appropriate free position
+ *	     information
+ *
+ * This function returns free bytes position in the OOB area. If you want
+ * to get all the free bytes information, then you should call
+ * mtd_ooblayout_free(mtd, section++, oobfree) until it returns -ERANGE.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+int mtd_ooblayout_free(struct mtd_info *mtd, int section,
+		       struct mtd_oob_region *oobfree)
+{
+	memset(oobfree, 0, sizeof(*oobfree));
+
+	if (section < 0)
+		return -EINVAL;
+
+	if (!mtd->ooblayout || !mtd->ooblayout->free)
+		return -ENOTSUPP;
+
+	return mtd->ooblayout->free(mtd, section, oobfree);
+}
+EXPORT_SYMBOL_GPL(mtd_ooblayout_free);
+
+/**
+ * mtd_ooblayout_find_region - Find the region attached to a specific byte
+ * @mtd: mtd info structure
+ * @byte: the byte we are searching for
+ * @sectionp: pointer where the section id will be stored
+ * @oobregion: used to retrieve the ECC position
+ * @iter: iterator function. Should be either mtd_ooblayout_free or
+ *	  mtd_ooblayout_ecc depending on the region type you're searching for
+ *
+ * This function returns the section id and oobregion information of a
+ * specific byte. For example, say you want to know where the 4th ECC byte is
+ * stored, you'll use:
+ *
+ * mtd_ooblayout_find_region(mtd, 3, &section, &oobregion, mtd_ooblayout_ecc);
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+static int mtd_ooblayout_find_region(struct mtd_info *mtd, int byte,
+				int *sectionp, struct mtd_oob_region *oobregion,
+				int (*iter)(struct mtd_info *,
+					    int section,
+					    struct mtd_oob_region *oobregion))
+{
+	int pos = 0, ret, section = 0;
+
+	memset(oobregion, 0, sizeof(*oobregion));
+
+	while (1) {
+		ret = iter(mtd, section, oobregion);
+		if (ret)
+			return ret;
+
+		if (pos + oobregion->length > byte)
+			break;
+
+		pos += oobregion->length;
+		section++;
+	}
+
+	/*
+	 * Adjust region info to make it start at the beginning at the
+	 * 'start' ECC byte.
+	 */
+	oobregion->offset += byte - pos;
+	oobregion->length -= byte - pos;
+	*sectionp = section;
+
+	return 0;
+}
+
+/**
+ * mtd_ooblayout_find_eccregion - Find the ECC region attached to a specific
+ *				  ECC byte
+ * @mtd: mtd info structure
+ * @eccbyte: the byte we are searching for
+ * @sectionp: pointer where the section id will be stored
+ * @oobregion: OOB region information
+ *
+ * Works like mtd_ooblayout_find_region() except it searches for a specific ECC
+ * byte.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,
+				 int *section,
+				 struct mtd_oob_region *oobregion)
+{
+	return mtd_ooblayout_find_region(mtd, eccbyte, section, oobregion,
+					 mtd_ooblayout_ecc);
+}
+EXPORT_SYMBOL_GPL(mtd_ooblayout_find_eccregion);
+
+/**
+ * mtd_ooblayout_get_bytes - Extract OOB bytes from the oob buffer
+ * @mtd: mtd info structure
+ * @buf: destination buffer to store OOB bytes
+ * @oobbuf: OOB buffer
+ * @start: first byte to retrieve
+ * @nbytes: number of bytes to retrieve
+ * @iter: section iterator
+ *
+ * Extract bytes attached to a specific category (ECC or free)
+ * from the OOB buffer and copy them into buf.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+static int mtd_ooblayout_get_bytes(struct mtd_info *mtd, u8 *buf,
+				const u8 *oobbuf, int start, int nbytes,
+				int (*iter)(struct mtd_info *,
+					    int section,
+					    struct mtd_oob_region *oobregion))
+{
+	struct mtd_oob_region oobregion;
+	int section, ret;
+
+	ret = mtd_ooblayout_find_region(mtd, start, &section,
+					&oobregion, iter);
+
+	while (!ret) {
+		int cnt;
+
+		cnt = min_t(int, nbytes, oobregion.length);
+		memcpy(buf, oobbuf + oobregion.offset, cnt);
+		buf += cnt;
+		nbytes -= cnt;
+
+		if (!nbytes)
+			break;
+
+		ret = iter(mtd, ++section, &oobregion);
+	}
+
+	return ret;
+}
+
+/**
+ * mtd_ooblayout_set_bytes - put OOB bytes into the oob buffer
+ * @mtd: mtd info structure
+ * @buf: source buffer to get OOB bytes from
+ * @oobbuf: OOB buffer
+ * @start: first OOB byte to set
+ * @nbytes: number of OOB bytes to set
+ * @iter: section iterator
+ *
+ * Fill the OOB buffer with data provided in buf. The category (ECC or free)
+ * is selected by passing the appropriate iterator.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+static int mtd_ooblayout_set_bytes(struct mtd_info *mtd, const u8 *buf,
+				u8 *oobbuf, int start, int nbytes,
+				int (*iter)(struct mtd_info *,
+					    int section,
+					    struct mtd_oob_region *oobregion))
+{
+	struct mtd_oob_region oobregion;
+	int section, ret;
+
+	ret = mtd_ooblayout_find_region(mtd, start, &section,
+					&oobregion, iter);
+
+	while (!ret) {
+		int cnt;
+
+		cnt = min_t(int, nbytes, oobregion.length);
+		memcpy(oobbuf + oobregion.offset, buf, cnt);
+		buf += cnt;
+		nbytes -= cnt;
+
+		if (!nbytes)
+			break;
+
+		ret = iter(mtd, ++section, &oobregion);
+	}
+
+	return ret;
+}
+
+/**
+ * mtd_ooblayout_count_bytes - count the number of bytes in a OOB category
+ * @mtd: mtd info structure
+ * @iter: category iterator
+ *
+ * Count the number of bytes in a given category.
+ *
+ * Returns a positive value on success, a negative error code otherwise.
+ */
+static int mtd_ooblayout_count_bytes(struct mtd_info *mtd,
+				int (*iter)(struct mtd_info *,
+					    int section,
+					    struct mtd_oob_region *oobregion))
+{
+	struct mtd_oob_region oobregion;
+	int section = 0, ret, nbytes = 0;
+
+	while (1) {
+		ret = iter(mtd, section++, &oobregion);
+		if (ret) {
+			if (ret == -ERANGE)
+				ret = nbytes;
+			break;
+		}
+
+		nbytes += oobregion.length;
+	}
+
+	return ret;
+}
+
+/**
+ * mtd_ooblayout_get_eccbytes - extract ECC bytes from the oob buffer
+ * @mtd: mtd info structure
+ * @eccbuf: destination buffer to store ECC bytes
+ * @oobbuf: OOB buffer
+ * @start: first ECC byte to retrieve
+ * @nbytes: number of ECC bytes to retrieve
+ *
+ * Works like mtd_ooblayout_get_bytes(), except it acts on ECC bytes.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf,
+			       const u8 *oobbuf, int start, int nbytes)
+{
+	return mtd_ooblayout_get_bytes(mtd, eccbuf, oobbuf, start, nbytes,
+				       mtd_ooblayout_ecc);
+}
+EXPORT_SYMBOL_GPL(mtd_ooblayout_get_eccbytes);
+
+/**
+ * mtd_ooblayout_set_eccbytes - set ECC bytes into the oob buffer
+ * @mtd: mtd info structure
+ * @eccbuf: source buffer to get ECC bytes from
+ * @oobbuf: OOB buffer
+ * @start: first ECC byte to set
+ * @nbytes: number of ECC bytes to set
+ *
+ * Works like mtd_ooblayout_set_bytes(), except it acts on ECC bytes.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf,
+			       u8 *oobbuf, int start, int nbytes)
+{
+	return mtd_ooblayout_set_bytes(mtd, eccbuf, oobbuf, start, nbytes,
+				       mtd_ooblayout_ecc);
+}
+EXPORT_SYMBOL_GPL(mtd_ooblayout_set_eccbytes);
+
+/**
+ * mtd_ooblayout_get_databytes - extract data bytes from the oob buffer
+ * @mtd: mtd info structure
+ * @databuf: destination buffer to store ECC bytes
+ * @oobbuf: OOB buffer
+ * @start: first ECC byte to retrieve
+ * @nbytes: number of ECC bytes to retrieve
+ *
+ * Works like mtd_ooblayout_get_bytes(), except it acts on free bytes.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf,
+				const u8 *oobbuf, int start, int nbytes)
+{
+	return mtd_ooblayout_get_bytes(mtd, databuf, oobbuf, start, nbytes,
+				       mtd_ooblayout_free);
+}
+EXPORT_SYMBOL_GPL(mtd_ooblayout_get_databytes);
+
+/**
+ * mtd_ooblayout_set_databytes - set data bytes into the oob buffer
+ * @mtd: mtd info structure
+ * @databuf: source buffer to get data bytes from
+ * @oobbuf: OOB buffer
+ * @start: first ECC byte to set
+ * @nbytes: number of ECC bytes to set
+ *
+ * Works like mtd_ooblayout_set_bytes(), except it acts on free bytes.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,
+				u8 *oobbuf, int start, int nbytes)
+{
+	return mtd_ooblayout_set_bytes(mtd, databuf, oobbuf, start, nbytes,
+				       mtd_ooblayout_free);
+}
+EXPORT_SYMBOL_GPL(mtd_ooblayout_set_databytes);
+
+/**
+ * mtd_ooblayout_count_freebytes - count the number of free bytes in OOB
+ * @mtd: mtd info structure
+ *
+ * Works like mtd_ooblayout_count_bytes(), except it count free bytes.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+int mtd_ooblayout_count_freebytes(struct mtd_info *mtd)
+{
+	return mtd_ooblayout_count_bytes(mtd, mtd_ooblayout_free);
+}
+EXPORT_SYMBOL_GPL(mtd_ooblayout_count_freebytes);
+
+/**
+ * mtd_ooblayout_count_eccbytes - count the number of ECC bytes in OOB
+ * @mtd: mtd info structure
+ *
+ * Works like mtd_ooblayout_count_bytes(), except it count ECC bytes.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd)
+{
+	return mtd_ooblayout_count_bytes(mtd, mtd_ooblayout_ecc);
+}
+EXPORT_SYMBOL_GPL(mtd_ooblayout_count_eccbytes);
+
+
+/**
+ * mtd_ecclayout_ecc - Default ooblayout_ecc iterator implementation
+ * @mtd: MTD device structure
+ * @section: ECC section. Depending on the layout you may have all the ECC
+ *	     bytes stored in a single contiguous section, or one section
+ *	     per ECC chunk (and sometime several sections for a single ECC
+ *	     ECC chunk)
+ * @oobecc: OOB region struct filled with the appropriate ECC position
+ *	    information
+ *
+ * This function is just a wrapper around the mtd->ecclayout field and is
+ * here to ease the transition to the mtd_ooblayout_ops approach.
+ * All it does is convert the layout->eccpos information into proper oob
+ * region definitions.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+static int mtd_ecclayout_ecc(struct mtd_info *mtd, int section,
+			     struct mtd_oob_region *oobecc)
+{
+	int eccbyte = 0, cursection = 0, length = 0, eccpos = 0;
+
+	if (!mtd->ecclayout)
+		return -ENOTSUPP;
+
+	/*
+	 * This logic allows us to reuse the ->ecclayout information and
+	 * expose them as ECC regions (as done for the OOB free regions).
+	 *
+	 * TODO: this should be dropped as soon as we get rid of the
+	 * ->ecclayout field.
+	 */
+	for (eccbyte = 0; eccbyte < mtd->ecclayout->eccbytes; eccbyte++) {
+		eccpos = mtd->ecclayout->eccpos[eccbyte];
+
+		if (eccbyte < mtd->ecclayout->eccbytes - 1) {
+			int neccpos = mtd->ecclayout->eccpos[eccbyte + 1];
+
+			if (eccpos + 1 == neccpos) {
+				length++;
+				continue;
+			}
+		}
+
+		if (section == cursection)
+			break;
+
+		length = 0;
+		cursection++;
+	}
+
+	if (cursection != section || eccbyte >= mtd->ecclayout->eccbytes)
+		return -ERANGE;
+
+	oobecc->length = length + 1;
+	oobecc->offset = eccpos - length;
+
+	return 0;
+}
+
+/**
+ * mtd_ecclayout_ecc - Default ooblayout_free iterator implementation
+ * @mtd: MTD device structure
+ * @section: Free section. Depending on the layout you may have all the free
+ *	     bytes stored in a single contiguous section, or one section
+ *	     per ECC chunk (and sometime several sections for a single ECC
+ *	     ECC chunk)
+ * @oobfree: OOB region struct filled with the appropriate free position
+ *	     information
+ *
+ * This function is just a wrapper around the mtd->ecclayout field and is
+ * here to ease the transition to the mtd_ooblayout_ops approach.
+ * All it does is convert the layout->oobfree information into proper oob
+ * region definitions.
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+static int mtd_ecclayout_free(struct mtd_info *mtd, int section,
+			      struct mtd_oob_region *oobfree)
+{
+	struct nand_ecclayout *layout = mtd->ecclayout;
+
+	if (!layout)
+		return -ENOTSUPP;
+
+	if (section >= MTD_MAX_OOBFREE_ENTRIES_LARGE ||
+	    !layout->oobfree[section].length)
+		return -ERANGE;
+
+	oobfree->offset = layout->oobfree[section].offset;
+	oobfree->length = layout->oobfree[section].length;
+
+	return 0;
+}
+
+static const struct mtd_ooblayout_ops mtd_ecclayout_wrapper_ops = {
+	.ecc = mtd_ecclayout_ecc,
+	.free = mtd_ecclayout_free,
+};
+
+/**
+ * mtd_set_ecclayout - Attach an ecclayout to an MTD device
+ * @mtd: MTD device structure
+ * @ecclayout: The ecclayout to attach to the device
+ *
+ * Returns zero on success, a negative error code otherwise.
+ */
+void mtd_set_ecclayout(struct mtd_info *mtd, struct nand_ecclayout *ecclayout)
+{
+	if (!mtd || !ecclayout)
+		return;
+
+	mtd->ecclayout = ecclayout;
+	mtd_set_ooblayout(mtd, &mtd_ecclayout_wrapper_ops);
+}
+EXPORT_SYMBOL_GPL(mtd_set_ecclayout);