From 66aaba3a07cb8e53878bbeabe54660a646b55a34 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Sun, 3 May 2020 17:53:41 +0200 Subject: [PATCH] ubi: Relax the 'no MLC' rule and allow MLCs operating in SLC mode The MTD layer provides an SLC mode (purely software emulation of SLC behavior) addressing the paired-pages corruption issue, which was the main reason for refusing attaching MLC NANDs to UBI. Relax this rule and allow partitions that have the MTD_EMULATE_SLC_ON_MLC flag set to be attached. Signed-off-by: Boris Brezillon Signed-off-by: Miquel Raynal Acked-by: Richard Weinberger Link: https://lore.kernel.org/linux-mtd/20200503155341.16712-9-miquel.raynal@bootlin.com --- drivers/mtd/ubi/build.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c index 12c02342149c..e85b04e9716b 100644 --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c @@ -867,8 +867,11 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, * Both UBI and UBIFS have been designed for SLC NAND and NOR flashes. * MLC NAND is different and needs special care, otherwise UBI or UBIFS * will die soon and you will lose all your data. + * Relax this rule if the partition we're attaching to operates in SLC + * mode. */ - if (mtd->type == MTD_MLCNANDFLASH) { + if (mtd->type == MTD_MLCNANDFLASH && + !(mtd->flags & MTD_SLC_ON_MLC_EMULATION)) { pr_err("ubi: refuse attaching mtd%d - MLC NAND is not supported\n", mtd->index); return -EINVAL;