nand: Move the sub-page read support enable to a flag

Use a flag instead of a hard-coded macro so that sub-page reads can be
enabled in other cases (such as on-die ecc).

This is the same as a5ff4f102937a3492bca4a9ff0c341d78813414c in Linux

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index d3b71a50adc00303e8c4d598da15b116d954fdf5..a2d06be99fcf4f3f0882671a514b36b4afecb7a3 100644 (file)
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -1245,7 +1245,8 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
                        if (unlikely(ops->mode == MTD_OOB_RAW))
                                ret = chip->ecc.read_page_raw(mtd, chip,
                                                              bufpoi, page);
-                       else if (!aligned && NAND_SUBPAGE_READ(chip) && !oob)
+                       else if (!aligned && NAND_HAS_SUBPAGE_READ(chip) &&
+                           !oob)
                                ret = chip->ecc.read_subpage(mtd, chip,
                                                        col, bytes, bufpoi);
                        else
@@ -1256,7 +1257,7 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
 
                        /* Transfer not aligned data */
                        if (!aligned) {
-                               if (!NAND_SUBPAGE_READ(chip) && !oob &&
+                               if (!NAND_HAS_SUBPAGE_READ(chip) && !oob &&
                                    !(mtd->ecc_stats.failed - stats.failed))
                                        chip->pagebuf = realpage;
                                memcpy(buf, chip->buffers->databuf + col, bytes);
@@ -3150,6 +3151,10 @@ int nand_scan_tail(struct mtd_info *mtd)
        /* Invalidate the pagebuffer reference */
        chip->pagebuf = -1;
 
+       /* Large page NAND with SOFT_ECC should support subpage reads */
+       if ((chip->ecc.mode == NAND_ECC_SOFT) && (chip->page_shift > 9))
+               chip->options |= NAND_SUBPAGE_READ;
+
        /* Fill in remaining MTD driver data */
        mtd->type = MTD_NANDFLASH;
        mtd->flags = (chip->options & NAND_ROM) ? MTD_CAP_ROM :

diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index f63e04b634d0195313e96801a645653e118ea71c..e9e904523a5acca89277321383521429e33f0930 100644 (file)
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -194,6 +194,9 @@ typedef enum {
 /* Device behaves just like nand, but is readonly */
 #define NAND_ROM               0x00000800
 
+/* Device supports subpage reads */
+#define NAND_SUBPAGE_READ       0x00001000
+
 /* Options valid for Samsung large page devices */
 #define NAND_SAMSUNG_LP_OPTIONS \
        (NAND_NO_PADDING | NAND_CACHEPRG | NAND_COPYBACK)
@@ -203,9 +206,7 @@ typedef enum {
 #define NAND_MUST_PAD(chip) (!(chip->options & NAND_NO_PADDING))
 #define NAND_HAS_CACHEPROG(chip) ((chip->options & NAND_CACHEPRG))
 #define NAND_HAS_COPYBACK(chip) ((chip->options & NAND_COPYBACK))
-/* Large page NAND with SOFT_ECC should support subpage reads */
-#define NAND_SUBPAGE_READ(chip) ((chip->ecc.mode == NAND_ECC_SOFT) \
-                                       && (chip->page_shift > 9))
+#define NAND_HAS_SUBPAGE_READ(chip) ((chip->options & NAND_SUBPAGE_READ))
 
 /* Non chip related options */
 /*