mtd: nand: allow drivers to request minimum alignment for passed buffer
In some cases, nand_do_{read,write}_ops is passed with unaligned
ops->datbuf. Drivers using DMA will be unhappy about unaligned
buffer.
The new struct member, buf_align, represents the minimum alignment
the driver require for the buffer. If the buffer passed from the
upper MTD layer does not have enough alignment, nand_do_*_ops will
use bufpoi.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[Linux commit: 477544c62a84d3bacd9f90ba75ffc16c04d78071]
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index be30059..90c6010 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -752,6 +752,7 @@
* setting the read-retry mode. Mostly needed for MLC NAND.
* @ecc: [BOARDSPECIFIC] ECC control structure
* @buffers: buffer structure for read/write
+ * @buf_align: minimum buffer alignment required by a platform
* @hwcontrol: platform-specific hardware control structure
* @erase: [REPLACEABLE] erase function
* @scan_bbt: [REPLACEABLE] function to scan bad block table
@@ -893,6 +894,7 @@
struct nand_ecc_ctrl ecc;
struct nand_buffers *buffers;
+ unsigned long buf_align;
struct nand_hw_control hwcontrol;
uint8_t *bbt;