mtd: nand: kill the the NAND_MAX_PAGESIZE/NAND_MAX_OOBSIZE for nand_buffers{}

The patch converts the arrays to buffer pointers for nand_buffers{}.

The cafe_nand.c is the only NAND_OWN_BUFFERS user which allocates
nand_buffers{} itself.

This patch disables the DMA for nand_scan_ident, and restores the DMA
status after we finish the nand_scan_ident. This way, we can get page
size and OOB size and use them to allocate cafe->dmabuf.

Since the cafe_nand.c uses the NAND_ECC_HW_SYNDROME ECC mode, we do not
allocate the buffers for @ecccalc and @ecccode.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

1 files changed, 6 insertions, 6 deletions

diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 32f8612469d8..520ebca11f5d 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -435,17 +435,17 @@ struct nand_ecc_ctrl {
 
 /**
  * struct nand_buffers - buffer structure for read/write
- * @ecccalc:    buffer for calculated ECC
- * @ecccode:    buffer for ECC read from flash
- * @databuf:    buffer for data - dynamically sized
+ * @ecccalc:    buffer pointer for calculated ECC, size is oobsize.
+ * @ecccode:    buffer pointer for ECC read from flash, size is oobsize.
+ * @databuf:    buffer pointer for data, size is (page size + oobsize).
  *
  * Do not change the order of buffers. databuf and oobrbuf must be in
  * consecutive order.
  */
 struct nand_buffers {
-        uint8_t ecccalc[NAND_MAX_OOBSIZE];
-        uint8_t ecccode[NAND_MAX_OOBSIZE];
-        uint8_t databuf[NAND_MAX_PAGESIZE + NAND_MAX_OOBSIZE];
+        uint8_t *ecccalc;
+        uint8_t *ecccode;
+        uint8_t *databuf;
 };
 
 /**