[PATCH 2/3] mtdblock: Add comment about UBI block devices

From: Ezequiel Garcia
Date: Sun Aug 01 2021 - 19:45:31 EST

There is a surprisingly large number of tutorials
that suggest using mtdblock to mount SquashFS filesystems
on flash devices, including NAND devices.

Given this approach is suboptimal than using UBI, and given
the UBI block device layer was introduced many years ago
specifically with this use case in mind, add a small
comment inviting users and developers to consider UBI block.

Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
drivers/mtd/Kconfig | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig
index 32bed6c63863..91cdbbd44317 100644
--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -151,6 +151,9 @@ config MTD_BLOCK_RO
You do not need this option for use with the DiskOnChip devices. For
those, enable NFTL support (CONFIG_NFTL) instead.

+comment "Note that in some cases UBI block is preferred. See MTD_UBI_BLOCK."
+ depends on MTD_BLOCK || MTD_BLOCK_RO
config FTL
tristate "FTL (Flash Translation Layer) support"
depends on BLOCK