mtd: rawnand: qcom: Add helper to check last code word

Add the qcom_nandc_is_last_cw() helper which checks if
the input cw index is the last one or not.
Signed-off-by: Md Sadre Alam <mdalam@codeaurora.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/1614109141-7531-2-git-send-email-mdalam@codeaurora.org

drivers/mtd/nand/raw/qcom_nandc.c

@@ -662,6 +662,12 @@ static void nandc_set_reg(struct nand_chip *chip, int offset,
 		*reg = cpu_to_le32(val);
 }
 
+/* Helper to check the code word, whether it is last cw or not */
+static bool qcom_nandc_is_last_cw(struct nand_ecc_ctrl *ecc, int cw)
+{
+	return cw == (ecc->steps - 1);
+}
+
 /* helper to configure address register values */
 static void set_address(struct qcom_nand_host *host, u16 column, int page)
 {
@@ -1629,7 +1635,7 @@ qcom_nandc_read_cw_raw(struct mtd_info *mtd, struct nand_chip *chip,
 	data_size1 = mtd->writesize - host->cw_size * (ecc->steps - 1);
 	oob_size1 = host->bbm_size;
 
-	if (cw == (ecc->steps - 1)) {
+	if (qcom_nandc_is_last_cw(ecc, cw)) {
 		data_size2 = ecc->size - data_size1 -
 			     ((ecc->steps - 1) * 4);
 		oob_size2 = (ecc->steps * 4) + host->ecc_bytes_hw +
@@ -1710,7 +1716,7 @@ check_for_erased_page(struct qcom_nand_host *host, u8 *data_buf,
 	}
 
 	for_each_set_bit(cw, &uncorrectable_cws, ecc->steps) {
-		if (cw == (ecc->steps - 1)) {
+		if (qcom_nandc_is_last_cw(ecc, cw)) {
 			data_size = ecc->size - ((ecc->steps - 1) * 4);
 			oob_size = (ecc->steps * 4) + host->ecc_bytes_hw;
 		} else {
@@ -1770,7 +1776,7 @@ static int parse_read_errors(struct qcom_nand_host *host, u8 *data_buf,
 		u32 flash, buffer, erased_cw;
 		int data_len, oob_len;
 
-		if (i == (ecc->steps - 1)) {
+		if (qcom_nandc_is_last_cw(ecc, i)) {
 			data_len = ecc->size - ((ecc->steps - 1) << 2);
 			oob_len = ecc->steps << 2;
 		} else {
@@ -1869,7 +1875,7 @@ static int read_page_ecc(struct qcom_nand_host *host, u8 *data_buf,
 	for (i = 0; i < ecc->steps; i++) {
 		int data_size, oob_size;
 
-		if (i == (ecc->steps - 1)) {
+		if (qcom_nandc_is_last_cw(ecc, i)) {
 			data_size = ecc->size - ((ecc->steps - 1) << 2);
 			oob_size = (ecc->steps << 2) + host->ecc_bytes_hw +
 				   host->spare_bytes;
@@ -2048,7 +2054,7 @@ static int qcom_nandc_write_page(struct nand_chip *chip, const uint8_t *buf,
 	for (i = 0; i < ecc->steps; i++) {
 		int data_size, oob_size;
 
-		if (i == (ecc->steps - 1)) {
+		if (qcom_nandc_is_last_cw(ecc, i)) {
 			data_size = ecc->size - ((ecc->steps - 1) << 2);
 			oob_size = (ecc->steps << 2) + host->ecc_bytes_hw +
 				   host->spare_bytes;
@@ -2068,7 +2074,7 @@ static int qcom_nandc_write_page(struct nand_chip *chip, const uint8_t *buf,
 		 * itself. For the last codeword, we skip the bbm positions and
 		 * write to the free oob area.
 		 */
-		if (i == (ecc->steps - 1)) {
+		if (qcom_nandc_is_last_cw(ecc, i)) {
 			oob_buf += host->bbm_size;
 
 			write_data_dma(nandc, FLASH_BUF_ACC + data_size,
@@ -2123,7 +2129,7 @@ static int qcom_nandc_write_page_raw(struct nand_chip *chip,
 		data_size1 = mtd->writesize - host->cw_size * (ecc->steps - 1);
 		oob_size1 = host->bbm_size;
 
-		if (i == (ecc->steps - 1)) {
+		if (qcom_nandc_is_last_cw(ecc, i)) {
 			data_size2 = ecc->size - data_size1 -
 				     ((ecc->steps - 1) << 2);
 			oob_size2 = (ecc->steps << 2) + host->ecc_bytes_hw +