From 65a2c1caa70f71690dcb5afd8fc6afe67fcde599 Mon Sep 17 00:00:00 2001 From: Sekhar Nori Date: Thu, 30 Mar 2017 20:09:30 +0530 Subject: [PATCH] mtd: nand: davinci: add comment on NAND subpage write status on keystone Add a comment clarifying that NAND subpage write on keystone works, but is not being enabled in the interest of backward compatibility. Signed-off-by: Sekhar Nori Signed-off-by: Boris Brezillon --- drivers/mtd/nand/davinci_nand.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/mtd/nand/davinci_nand.c b/drivers/mtd/nand/davinci_nand.c index 27fa8b8..531c519 100644 --- a/drivers/mtd/nand/davinci_nand.c +++ b/drivers/mtd/nand/davinci_nand.c @@ -581,6 +581,17 @@ static struct davinci_nand_pdata "ti,davinci-nand-use-bbt")) pdata->bbt_options = NAND_BBT_USE_FLASH; + /* + * Since kernel v4.8, this driver has been fixed to enable + * use of 4-bit hardware ECC with subpages and verified on + * TI's keystone EVMs (K2L, K2HK and K2E). + * However, in the interest of not breaking systems using + * existing UBI partitions, sub-page writes are not being + * (re)enabled. If you want to use subpage writes on Keystone + * platforms (i.e. do not have any existing UBI partitions), + * then use "ti,davinci-nand" as the compatible in your + * device-tree file. + */ if (of_device_is_compatible(pdev->dev.of_node, "ti,keystone-nand")) { pdata->options |= NAND_NO_SUBPAGE_WRITE; -- 2.7.4