4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Miquel Raynal <miquel.raynal@xxxxxxxxxxxxxxxxxx>
commit f4c6cd1a7f2275d5bc0e494b21fff26f8dde80f0 upstream.
When the requested ECC strength does not exactly match the strengths
supported by the ECC engine, the driver is selecting the closest
strength meeting the 'selected_strength > requested_strength'
constraint. Fix the fact that, in this particular case, ecc->strength
value was not updated to match the 'selected_strength'.
For instance, one can encounter this issue when no ECC requirement is
filled in the device tree while the NAND chip minimum requirement is not
a strength/step_size combo natively supported by the ECC engine.
Fixes: 1fef62c1423b ("mtd: nand: add sunxi NAND flash controller support")
Suggested-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mtd/nand/sunxi_nand.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
--- a/drivers/mtd/nand/sunxi_nand.c
+++ b/drivers/mtd/nand/sunxi_nand.c
@@ -1835,8 +1835,14 @@ static int sunxi_nand_hw_common_ecc_ctrl
/* Add ECC info retrieval from DT */
for (i = 0; i < ARRAY_SIZE(strengths); i++) {
- if (ecc->strength <= strengths[i])
+ if (ecc->strength <= strengths[i]) {
+ /*
+ * Update ecc->strength value with the actual strength
+ * that will be used by the ECC engine.
+ */
+ ecc->strength = strengths[i];
break;
+ }
}
if (i >= ARRAY_SIZE(strengths)) {