forge/linux-pinenote
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

mtd: nand: Add support to use nand_base poi databuf as bounce buffer

Browse source 
nand_base can be passed a kmap()'d buffers from highmem by
filesystems like jffs2. This results in failure to map the
physical address of the DMA buffer on various contoller
driver on different platforms. This change adds a chip option
to use preallocated databuf as bounce buffers used in
nand_do_read_ops() and nand_do_write_ops().
This allows for specific nand controller driver to set this
option as needed.

Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
This commit is contained in:
Kamal Dasu 2014-05-01 20:51:19 -04:00 • committed by Brian Norris
parent 6e5221558d
commit 66507c7bc8
2 changed files with 36 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

5
include/linux/mtd/nand.h
View file

@ -175,6 +175,11 @@ typedef enum {
#define NAND_OWN_BUFFERS 0x00020000
/* Chip may not exist, so silence any errors in scan */
#define NAND_SCAN_SILENT_NODEV 0x00040000
/*
* This option could be defined by controller drivers to protect against
* kmap'ed, vmalloc'ed highmem buffers being passed from upper layers
*/
#define NAND_USE_BOUNCE_BUFFER 0x00080000
/*
* Autodetect nand buswidth with readid/onfi.
* This suppose the driver will configure the hardware in 8 bits mode