[PATCH v3] mtd: atmel_nand: use minimum ecc requirements of nand: ecc_{strength, step}_ds

[Josh Wu]

Since ecc_{strength,step}_ds is introduced in nand_chip structure for
minimum ecc requirements. So we can use them directly and remove our
own get_onfi_ecc_param function.

Signed-off-by: Josh Wu <josh.wu at atmel.com>
---
v2 --> v3:
  1. since ecc_{strength,step}_ds is non ONFI specific remove the check code:
        'if (host->nand_chip.onfi_version)'
     use 'if (host->nand_chip.ecc_strength_ds)' instead.
  2. refined the commit message and change the comment since now we are not
     ONFI specific.

v1 --> v2:
  1. updated the refered commit id as it is changed when merged in mainline.
  2. refined the commit message

 drivers/mtd/nand/atmel_nand.c |   46 ++++++++---------------------------------
 1 file changed, 9 insertions(+), 37 deletions(-)

diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
index 5a5d457..46e8794 100644
--- a/drivers/mtd/nand/atmel_nand.c
+++ b/drivers/mtd/nand/atmel_nand.c
@@ -1062,56 +1062,28 @@ static void atmel_pmecc_core_init(struct mtd_info *mtd)
 }
 
 /*
- * Get ECC requirement in ONFI parameters, returns -1 if ONFI
- * parameters is not supported.
- * return 0 if success to get the ECC requirement.
- */
-static int get_onfi_ecc_param(struct nand_chip *chip,
-		int *ecc_bits, int *sector_size)
-{
-	*ecc_bits = *sector_size = 0;
-
-	if (chip->onfi_params.ecc_bits == 0xff)
-		/* TODO: the sector_size and ecc_bits need to be find in
-		 * extended ecc parameter, currently we don't support it.
-		 */
-		return -1;
-
-	*ecc_bits = chip->onfi_params.ecc_bits;
-
-	/* The default sector size (ecc codeword size) is 512 */
-	*sector_size = 512;
-
-	return 0;
-}
-
-/*
- * Get ecc requirement from ONFI parameters ecc requirement.
+ * Get minimum ecc requirements from NAND.
  * If pmecc-cap, pmecc-sector-size in DTS are not specified, this function
- * will set them according to ONFI ecc requirement. Otherwise, use the
+ * will set them according to minimum ecc requirement. Otherwise, use the
  * value in DTS file.
  * return 0 if success. otherwise return error code.
  */
 static int pmecc_choose_ecc(struct atmel_nand_host *host,
 		int *cap, int *sector_size)
 {
-	/* Get ECC requirement from ONFI parameters */
-	*cap = *sector_size = 0;
-	if (host->nand_chip.onfi_version) {
-		if (!get_onfi_ecc_param(&host->nand_chip, cap, sector_size))
-			dev_info(host->dev, "ONFI params, minimum required ECC: %d bits in %d bytes\n",
+	/* Get minimum ECC requirements */
+	if (host->nand_chip.ecc_strength_ds) {
+		*cap = host->nand_chip.ecc_strength_ds;
+		*sector_size = host->nand_chip.ecc_step_ds;
+		dev_info(host->dev, "minimum ECC requirements: %d bits in %d bytes\n",
 				*cap, *sector_size);
-		else
-			dev_info(host->dev, "NAND chip ECC reqirement is in Extended ONFI parameter, we don't support yet.\n");
 	} else {
-		dev_info(host->dev, "NAND chip is not ONFI compliant, assume ecc_bits is 2 in 512 bytes");
-	}
-	if (*cap == 0 && *sector_size == 0) {
 		*cap = 2;
 		*sector_size = 512;
+		dev_info(host->dev, "cannot detect minimum ECC requirements, assume 2-bit correction per 512 bytes");
 	}
 
-	/* If dts file doesn't specify then use the one in ONFI parameters */
+	/* If dts file doesn't specify then use the NAND's minimum ecc parameters */
 	if (host->pmecc_corr_cap == 0) {
 		/* use the most fitable ecc bits (the near bigger one ) */
 		if (*cap <= 2)
-- 
1.7.9.5