[PATCH V6] mtd: rawnand: qcom: Update code word value for raw read

[Md Sadre Alam]

>From QPIC V2 onwards there is a separate register to read
last code word "QPIC_NAND_READ_LOCATION_LAST_CW_n".

qcom_nandc_read_cw_raw() is used to read only one code word
at a time. If we will configure number of code words to 1 in
in QPIC_NAND_DEV0_CFG0 register then QPIC controller thinks
its reading the last code word, since from QPIC V2 onwards
we are having separate register to read the last code word,
we have to configure "QPIC_NAND_READ_LOCATION_LAST_CW_n"
register to fetch data from controller buffer to system
memory.

Fixes: 503ee5aad430 ("mtd: rawnand: qcom: update last code word register")
Cc: stable at kernel.org
Signed-off-by: Md Sadre Alam <mdalam at codeaurora.org>
---
Changes in V6:

 * Incorporated "commit hash" comment from Miquèl
 * updated commit hash to 12 digits in Fixes tag.

Changes in V5:

 * Incorporated "hash commit" comment from Mani.
 * Updated commit hash

Changes in V4:

 * Incorporated "Change log" comment from Miquèl
 * Updated change log

Changes in V3:
 
 * Incorporated "Fixes tags are missing" comment from Miquèl
 * Added Fixes tag Fixes:503ee5aa ("mtd: rawnand: qcom: update last code word register")


Changes in V2:

 * Incorporated "stable tags are missing" comment from Miquèl
 * Added stable tags Cc:stable at kernel.org

 drivers/mtd/nand/raw/qcom_nandc.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
index ef0bade..04e6f7b 100644
--- a/drivers/mtd/nand/raw/qcom_nandc.c
+++ b/drivers/mtd/nand/raw/qcom_nandc.c
@@ -1676,13 +1676,17 @@ qcom_nandc_read_cw_raw(struct mtd_info *mtd, struct nand_chip *chip,
 	struct nand_ecc_ctrl *ecc = &chip->ecc;
 	int data_size1, data_size2, oob_size1, oob_size2;
 	int ret, reg_off = FLASH_BUF_ACC, read_loc = 0;
+	int raw_cw = cw;
 
 	nand_read_page_op(chip, page, 0, NULL, 0);
 	host->use_ecc = false;
 
+	if (nandc->props->qpic_v2)
+		raw_cw = ecc->steps - 1;
+
 	clear_bam_transaction(nandc);
 	set_address(host, host->cw_size * cw, page);
-	update_rw_regs(host, 1, true, cw);
+	update_rw_regs(host, 1, true, raw_cw);
 	config_nand_page_read(chip);
 
 	data_size1 = mtd->writesize - host->cw_size * (ecc->steps - 1);
@@ -1711,7 +1715,7 @@ qcom_nandc_read_cw_raw(struct mtd_info *mtd, struct nand_chip *chip,
 		nandc_set_read_loc(chip, cw, 3, read_loc, oob_size2, 1);
 	}
 
-	config_nand_cw_read(chip, false, cw);
+	config_nand_cw_read(chip, false, raw_cw);
 
 	read_data_dma(nandc, reg_off, data_buf, data_size1, 0);
 	reg_off += data_size1;
-- 
2.7.4