Re: [RESEND v5 09/21] mtd: rawnand: Create a new enumeration to describe properly ECC types

On Wed, 27 May 2020 10:44:30 +0200
Boris Brezillon [off-list ref] wrote:

On Wed, 27 May 2020 10:33:56 +0200
Miquel Raynal [off-list ref] wrote:

quoted

Boris Brezillon [off-list ref] wrote on Wed, 27 May
2020 00:59:28 +0200:
  

quoted

On Tue, 26 May 2020 21:56:21 +0200
Miquel Raynal [off-list ref] wrote:
    

quoted

Now that the misleading mix between ECC engine type and OOB placement
has been addressed, add a new enumeration to properly define ECC types
(also called provider or mode).

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
---
 drivers/mtd/nand/raw/nand_base.c |  7 +++++++
 include/linux/mtd/rawnand.h      | 16 ++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
index 515cd4681660..5c6ab5b93270 100644
--- a/drivers/mtd/nand/raw/nand_base.c
+++ b/drivers/mtd/nand/raw/nand_base.c

@@ -5018,6 +5018,13 @@ static const char * const nand_ecc_modes[] = {
 	[NAND_ECC_ON_DIE]	= "on-die",
 };
 
+static const char * const nand_ecc_engine_providers[] = {      

This table is not used here, are you sure it should be introduced now?
    

quoted

+	[NAND_ECC_ENGINE_NONE] = "none",
+	[NAND_ECC_ENGINE_SOFT] = "soft",
+	[NAND_ECC_ENGINE_CONTROLLER] = "hw",      

					^ "on-controller" ?    

This would break DT backward compatibility, I am afraid I cannot do
that.  

You can always keep a translation table for the old prop
(nand-ecc-mode) and have a new one for the new prop
(nand-ecc-engine-type). But maybe you're not introducing a new property
in this series, in which case the translation table here is just fine.

BTW, this DT prop is more a way to select among several ECC engines when
you have a choice, so maybe it should be named
nand-use-ecc-engine-type/nand-select-ecc-engine-type instead of
nand-ecc-provider/nand-ecc-engine-type.