[MTD] [NAND] S3C2410 Large page NAND support

This adds support for using large page NAND devices
with the S3C24XX NAND controller. This also adds the
file Documentation/arm/Samsung-S3C24XX/NAND.txt to
describe the differences.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 33 insertions, 5 deletions

diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
index 8557c68dbb42..15397e0f3965 100644
--- a/drivers/mtd/nand/s3c2410.c
+++ b/drivers/mtd/nand/s3c2410.c
@@ -472,7 +472,7 @@ static int s3c2440_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u
         ecc_code[1] = ecc >> 8;
         ecc_code[2] = ecc >> 16;
 
-        pr_debug("%s: returning ecc %06lx\n", __func__, ecc);
+        pr_debug("%s: returning ecc %06lx\n", __func__, ecc & 0xffffff);
 
         return 0;
 }
@@ -643,9 +643,6 @@ static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
                 chip->ecc.calculate = s3c2410_nand_calculate_ecc;
                 chip->ecc.correct   = s3c2410_nand_correct_data;
                 chip->ecc.mode      = NAND_ECC_HW;
-                chip->ecc.size      = 512;
-                chip->ecc.bytes     = 3;
-                chip->ecc.layout    = &nand_hw_eccoob;
 
                 switch (info->cpu_type) {
                 case TYPE_S3C2410:
@@ -669,6 +666,34 @@ static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
         }
 }
 
+/* s3c2410_nand_update_chip
+ *
+ * post-probe chip update, to change any items, such as the
+ * layout for large page nand
+ */
+
+static void s3c2410_nand_update_chip(struct s3c2410_nand_info *info,
+                                     struct s3c2410_nand_mtd *nmtd)
+{
+        struct nand_chip *chip = &nmtd->chip;
+
+        printk("%s: chip %p: %d\n", __func__, chip, chip->page_shift);
+
+        if (hardware_ecc) {
+                /* change the behaviour depending on wether we are using
+                 * the large or small page nand device */
+
+                if (chip->page_shift > 10) {
+                        chip->ecc.size      = 256;
+                        chip->ecc.bytes     = 3;
+                } else {
+                        chip->ecc.size      = 512;
+                        chip->ecc.bytes     = 3;
+                        chip->ecc.layout    = &nand_hw_eccoob;
+                }
+        }
+}
+
 /* s3c2410_nand_probe
  *
  * called by device layer when it finds a device matching
@@ -775,9 +800,12 @@ static int s3c24xx_nand_probe(struct platform_device *pdev,
 
                 s3c2410_nand_init_chip(info, nmtd, sets);
 
-                nmtd->scan_res = nand_scan(&nmtd->mtd, (sets) ? sets->nr_chips : 1);
+                nmtd->scan_res = nand_scan_ident(&nmtd->mtd,
+                                                 (sets) ? sets->nr_chips : 1);
 
                 if (nmtd->scan_res == 0) {
+                        s3c2410_nand_update_chip(info, nmtd);
+                        nand_scan_tail(&nmtd->mtd);
                         s3c2410_nand_add_partition(info, nmtd, sets);
                 }