3 files changed, 16 insertions, 9 deletions

diff --git a/drivers/mtd/nand/denali.c b/drivers/mtd/nand/denali.c
index 154b033b4e8e..370b9dd7a278 100644
--- a/drivers/mtd/nand/denali.c
+++ b/drivers/mtd/nand/denali.c
@@ -1520,7 +1520,7 @@ int denali_init(struct denali_nand_info *denali)
          * so just let controller do 15bit ECC for MLC and 8bit ECC for
          * SLC if possible.
          * */
-        if (denali->nand.cellinfo & NAND_CI_CELLTYPE_MSK &&
+        if (!nand_is_slc(&denali->nand) &&
                         (denali->mtd.oobsize > (denali->bbtskipbytes +
                         ECC_15BITS * (denali->mtd.writesize /
                         ECC_SECTOR_SIZE)))) {
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 0b39d0c03f1e..6ea66270dbf5 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -3108,8 +3108,7 @@ static void nand_decode_ext_id(struct mtd_info *mtd, struct nand_chip *chip,
          * ID to decide what to do.
          */
         if (id_len == 6 && id_data[0] == NAND_MFR_SAMSUNG &&
-                        (chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
-                        id_data[5] != 0x00) {
+                        !nand_is_slc(chip) && id_data[5] != 0x00) {
                 /* Calc pagesize */
                 mtd->writesize = 2048 << (extid & 0x03);
                 extid >>= 2;
@@ -3141,7 +3140,7 @@ static void nand_decode_ext_id(struct mtd_info *mtd, struct nand_chip *chip,
                         (((extid >> 1) & 0x04) | (extid & 0x03));
                 *busw = 0;
         } else if (id_len == 6 && id_data[0] == NAND_MFR_HYNIX &&
-                        (chip->cellinfo & NAND_CI_CELLTYPE_MSK)) {
+                        !nand_is_slc(chip)) {
                 unsigned int tmp;
 
                 /* Calc pagesize */
@@ -3204,7 +3203,7 @@ static void nand_decode_ext_id(struct mtd_info *mtd, struct nand_chip *chip,
                  * - ID byte 5, bit[7]:    1 -> BENAND, 0 -> raw SLC
                  */
                 if (id_len >= 6 && id_data[0] == NAND_MFR_TOSHIBA &&
-                                !(chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
+                                nand_is_slc(chip) &&
                                 (id_data[5] & 0x7) == 0x6 /* 24nm */ &&
                                 !(id_data[4] & 0x80) /* !BENAND */) {
                         mtd->oobsize = 32 * mtd->writesize >> 9;
@@ -3265,11 +3264,11 @@ static void nand_decode_bbm_options(struct mtd_info *mtd,
          * Micron devices with 2KiB pages and on SLC Samsung, Hynix, Toshiba,
          * AMD/Spansion, and Macronix.  All others scan only the first page.
          */
-        if ((chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
+        if (!nand_is_slc(chip) &&
                         (maf_id == NAND_MFR_SAMSUNG ||
                          maf_id == NAND_MFR_HYNIX))
                 chip->bbt_options |= NAND_BBT_SCANLASTPAGE;
-        else if ((!(chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
+        else if ((nand_is_slc(chip) &&
                                 (maf_id == NAND_MFR_SAMSUNG ||
                                  maf_id == NAND_MFR_HYNIX ||
                                  maf_id == NAND_MFR_TOSHIBA ||
@@ -3745,8 +3744,7 @@ int nand_scan_tail(struct mtd_info *mtd)
         chip->ecc.total = chip->ecc.steps * chip->ecc.bytes;
 
         /* Allow subpage writes up to ecc.steps. Not possible for MLC flash */
-        if (!(chip->options & NAND_NO_SUBPAGE_WRITE) &&
-            !(chip->cellinfo & NAND_CI_CELLTYPE_MSK)) {
+        if (!(chip->options & NAND_NO_SUBPAGE_WRITE) && nand_is_slc(chip)) {
                 switch (chip->ecc.steps) {
                 case 2:
                         mtd->subpage_sft = 1;
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 129548169400..5c05bab0ad89 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -795,4 +795,13 @@ static inline int onfi_get_sync_timing_mode(struct nand_chip *chip)
         return le16_to_cpu(chip->onfi_params.src_sync_timing_mode);
 }
 
+/*
+ * Check if it is a SLC nand.
+ * The !nand_is_slc() can be used to check the MLC/TLC nand chips.
+ * We do not distinguish the MLC and TLC now.
+ */
+static inline bool nand_is_slc(struct nand_chip *chip)
+{
+        return !(chip->cellinfo & NAND_CI_CELLTYPE_MSK);
+}
 #endif /* __LINUX_MTD_NAND_H */