[PATCH v2] mtd: nand: ecc: Rework Kconfig dependencies

[Miquel Raynal]

Unlike "depends on", "select" does not enforce any type (y or m), which
can lead to the following situation:
* SPI_MXIC=y expects the NAND symbols to be built statically
* SPI_MXIC depends on MTD_NAND_ECC
* MTD_NAND_ECC selects MTD_NAND_CORE
In this case MTD_NAND_CORE=m is "valid" but will trigger 'undefined
reference' link errors.

The cleanest way to handle the situation is to use a "depends on"
between MTD_NAND_ECC and MTD_NAND_CORE to avoid such situations.

While at modifying the MTD_NAND_ECC symbol, fix the spacing.

Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
Reviewed-by: Pratyush Yadav <p.yadav at ti.com>
---

Changes in v2:
* Pratyush Ack.
* Stopped quoting a missing error log. Mentioned the 'undefined
  reference' link error instead.

 drivers/mtd/nand/Kconfig | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index 8431292ff49d..1b5f5bac3e6e 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -12,13 +12,13 @@ source "drivers/mtd/nand/spi/Kconfig"
 menu "ECC engine support"
 
 config MTD_NAND_ECC
-       bool
-       select MTD_NAND_CORE
+	bool
+	depends on MTD_NAND_CORE
 
 config MTD_NAND_ECC_SW_HAMMING
 	bool "Software Hamming ECC engine"
+	depends on MTD_NAND_ECC
 	default y if MTD_RAW_NAND
-	select MTD_NAND_ECC
 	help
 	  This enables support for software Hamming error
 	  correction. This correction can correct up to 1 bit error
@@ -37,8 +37,8 @@ config MTD_NAND_ECC_SW_HAMMING_SMC
 
 config MTD_NAND_ECC_SW_BCH
 	bool "Software BCH ECC engine"
+	depends on MTD_NAND_ECC
 	select BCH
-	select MTD_NAND_ECC
 	default n
 	help
 	  This enables support for software BCH error correction. Binary BCH
@@ -48,7 +48,7 @@ config MTD_NAND_ECC_SW_BCH
 
 config MTD_NAND_ECC_MXIC
 	bool "Macronix external hardware ECC engine"
-	select MTD_NAND_ECC
+	depends on MTD_NAND_ECC
 	help
 	  This enables support for the hardware ECC engine from Macronix.
 
-- 
2.27.0