4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Brent Taylor <motobud@xxxxxxxxx>
commit 30863e38ebeb500a31cecee8096fb5002677dd9b upstream.
When mtdoops calls mtd_panic_write(), it eventually calls
panic_nand_write() in nand_base.c. In order to properly wait for the
nand chip to be ready in panic_nand_wait(), the chip must first be
selected.
When using the atmel nand flash controller, a panic would occur due to
a NULL pointer exception.
Fixes: 2af7c6539931 ("mtd: Add panic_write for NAND flashes")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Brent Taylor <motobud@xxxxxxxxx>
Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mtd/nand/nand_base.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2663,15 +2663,18 @@ static int panic_nand_write(struct mtd_i
size_t *retlen, const uint8_t *buf)
{
struct nand_chip *chip = mtd->priv;
+ int chipnr = (int)(to >> chip->chip_shift);
struct mtd_oob_ops ops;
int ret;
- /* Wait for the device to get ready */
- panic_nand_wait(mtd, chip, 400);
-
/* Grab the device */
panic_nand_get_device(chip, mtd, FL_WRITING);
+ chip->select_chip(mtd, chipnr);
+
+ /* Wait for the device to get ready */
+ panic_nand_wait(mtd, chip, 400);
+
memset(&ops, 0, sizeof(ops));
ops.len = len;
ops.datbuf = (uint8_t *)buf;