[MTD] OneNAND: Select correct chip's bufferRAM for DDP

OneNAND double-density package (DDP) has two chips, each with
their own bufferRAM.  The driver will skip loading data from
the NAND core if the data can be found in a bufferRAM, however
in that case, the correct chip's bufferRAM must be selected
before reading from bufferRAM.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>

diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index f690c1916d1d03674a8dca560fc039ca9d0a3ec8..779327b845d19e1b83a8867a1e5dac59d6d5df01 100644 (file)
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -577,7 +577,7 @@ static int onenand_write_bufferram(struct mtd_info *mtd, int area,
 static int onenand_check_bufferram(struct mtd_info *mtd, loff_t addr)
 {
        struct onenand_chip *this = mtd->priv;
-       int blockpage;
+       int blockpage, found = 0;
        unsigned int i;
 
        blockpage = (int) (addr >> this->page_shift);
@@ -585,16 +585,24 @@ static int onenand_check_bufferram(struct mtd_info *mtd, loff_t addr)
        /* Is there valid data? */
        i = ONENAND_CURRENT_BUFFERRAM(this);
        if (this->bufferram[i].blockpage == blockpage)
-               return 1;
+               found = 1;
+       else {
+               /* Check another BufferRAM */
+               i = ONENAND_NEXT_BUFFERRAM(this);
+               if (this->bufferram[i].blockpage == blockpage) {
+                       ONENAND_SET_NEXT_BUFFERRAM(this);
+                       found = 1;
+               }
+       }
 
-       /* Check another BufferRAM */
-       i = ONENAND_NEXT_BUFFERRAM(this);
-       if (this->bufferram[i].blockpage == blockpage) {
-               ONENAND_SET_NEXT_BUFFERRAM(this);
-               return 1;
+       if (found && ONENAND_IS_DDP(this)) {
+               /* Select DataRAM for DDP */
+               int block = (int) (addr >> this->erase_shift);
+               int value = onenand_bufferram_address(this, block);
+               this->write_word(value, this->base + ONENAND_REG_START_ADDRESS2);
        }
 
-       return 0;
+       return found;
 }
 
 /**