Merge tag 'for-linus-20130301' of git://git.infradead.org/linux-mtd

Pull MTD update from David Woodhouse:
 "Fairly unexciting MTD merge for 3.9:

   - misc clean-ups in the MTD command-line partitioning parser
     (cmdlinepart)
   - add flash locking support for STmicro chips serial flash chips, as
     well as for CFI command set 2 chips.
   - new driver for the ELM error correction HW module found in various
     TI chips, enable the OMAP NAND driver to use the ELM HW error
     correction
   - added number of new serial flash IDs
   - various fixes and improvements in the gpmi NAND driver
   - bcm47xx NAND driver improvements
   - make the mtdpart module actually removable"

* tag 'for-linus-20130301' of git://git.infradead.org/linux-mtd: (45 commits)
  mtd: map: BUG() in non handled cases
  mtd: bcm47xxnflash: use pr_fmt for module prefix in messages
  mtd: davinci_nand: Use managed resources
  mtd: mtd_torturetest can cause stack overflows
  mtd: physmap_of: Convert device allocation to managed devm_kzalloc()
  mtd: at91: atmel_nand: for PMECC, add code to check the ONFI parameter ECC requirement.
  mtd: atmel_nand: make pmecc-cap, pmecc-sector-size in dts is optional.
  mtd: atmel_nand: avoid to report an error when lookup table offset is 0.
  mtd: bcm47xxsflash: adjust names of bus-specific functions
  mtd: bcm47xxpart: improve probing of nvram partition
  mtd: bcm47xxpart: add support for other erase sizes
  mtd: bcm47xxnflash: register this as normal driver
  mtd: bcm47xxnflash: fix message
  mtd: bcm47xxsflash: register this as normal driver
  mtd: bcm47xxsflash: write number of written bytes
  mtd: gpmi: add sanity check for the ECC
  mtd: gpmi: set the Golois Field bit for mx6q's BCH
  mtd: devices: elm: Removes <xx> literals in elm DT node
  mtd: gpmi: fix a dereferencing freed memory error
  mtd: fix the wrong timeo for panic_nand_wait()
  ...

1 files changed, 39 insertions, 24 deletions

diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
index e9b1c47e3cf9..717881a3d1b8 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
@@ -94,6 +94,25 @@ static inline int get_ecc_strength(struct gpmi_nand_data *this)
 	return round_down(ecc_strength, 2);
 }
 
+static inline bool gpmi_check_ecc(struct gpmi_nand_data *this)
+{
+	struct bch_geometry *geo = &this->bch_geometry;
+
+	/* Do the sanity check. */
+	if (GPMI_IS_MX23(this) || GPMI_IS_MX28(this)) {
+		/* The mx23/mx28 only support the GF13. */
+		if (geo->gf_len == 14)
+			return false;
+
+		if (geo->ecc_strength > MXS_ECC_STRENGTH_MAX)
+			return false;
+	} else if (GPMI_IS_MX6Q(this)) {
+		if (geo->ecc_strength > MX6_ECC_STRENGTH_MAX)
+			return false;
+	}
+	return true;
+}
+
 int common_nfc_set_geometry(struct gpmi_nand_data *this)
 {
 	struct bch_geometry *geo = &this->bch_geometry;
@@ -112,17 +131,24 @@ int common_nfc_set_geometry(struct gpmi_nand_data *this)
 	/* The default for the length of Galois Field. */
 	geo->gf_len = 13;
 
-	/* The default for chunk size. There is no oobsize greater then 512. */
+	/* The default for chunk size. */
 	geo->ecc_chunk_size = 512;
-	while (geo->ecc_chunk_size < mtd->oobsize)
+	while (geo->ecc_chunk_size < mtd->oobsize) {
 		geo->ecc_chunk_size *= 2; /* keep C >= O */
+		geo->gf_len = 14;
+	}
 
 	geo->ecc_chunk_count = mtd->writesize / geo->ecc_chunk_size;
 
 	/* We use the same ECC strength for all chunks. */
 	geo->ecc_strength = get_ecc_strength(this);
-	if (!geo->ecc_strength) {
-		pr_err("wrong ECC strength.\n");
+	if (!gpmi_check_ecc(this)) {
+		dev_err(this->dev,
+			"We can not support this nand chip."
+			" Its required ecc strength(%d) is beyond our"
+			" capability(%d).\n", geo->ecc_strength,
+			(GPMI_IS_MX6Q(this) ? MX6_ECC_STRENGTH_MAX
+					: MXS_ECC_STRENGTH_MAX));
 		return -EINVAL;
 	}
 
@@ -920,8 +946,7 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
 	dma_addr_t    auxiliary_phys;
 	unsigned int  i;
 	unsigned char *status;
-	unsigned int  failed;
-	unsigned int  corrected;
+	unsigned int  max_bitflips = 0;
 	int           ret;
 
 	pr_debug("page number is : %d\n", page);
@@ -945,35 +970,25 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
 			payload_virt, payload_phys);
 	if (ret) {
 		pr_err("Error in ECC-based read: %d\n", ret);
-		goto exit_nfc;
+		return ret;
 	}
 
 	/* handle the block mark swapping */
 	block_mark_swapping(this, payload_virt, auxiliary_virt);
 
 	/* Loop over status bytes, accumulating ECC status. */
-	failed		= 0;
-	corrected	= 0;
-	status		= auxiliary_virt + nfc_geo->auxiliary_status_offset;
+	status = auxiliary_virt + nfc_geo->auxiliary_status_offset;
 
 	for (i = 0; i < nfc_geo->ecc_chunk_count; i++, status++) {
 		if ((*status == STATUS_GOOD) || (*status == STATUS_ERASED))
 			continue;
 
 		if (*status == STATUS_UNCORRECTABLE) {
-			failed++;
+			mtd->ecc_stats.failed++;
 			continue;
 		}
-		corrected += *status;
-	}
-
-	/*
-	 * Propagate ECC status to the owning MTD only when failed or
-	 * corrected times nearly reaches our ECC correction threshold.
-	 */
-	if (failed || corrected >= (nfc_geo->ecc_strength - 1)) {
-		mtd->ecc_stats.failed    += failed;
-		mtd->ecc_stats.corrected += corrected;
+		mtd->ecc_stats.corrected += *status;
+		max_bitflips = max_t(unsigned int, max_bitflips, *status);
 	}
 
 	if (oob_required) {
@@ -995,8 +1010,8 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
 			this->payload_virt, this->payload_phys,
 			nfc_geo->payload_size,
 			payload_virt, payload_phys);
-exit_nfc:
-	return ret;
+
+	return max_bitflips;
 }
 
 static int gpmi_ecc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
@@ -1668,8 +1683,8 @@ exit_nfc_init:
 	release_resources(this);
 exit_acquire_resources:
 	platform_set_drvdata(pdev, NULL);
-	kfree(this);
 	dev_err(this->dev, "driver registration failed: %d\n", ret);
+	kfree(this);
 
 	return ret;
 }