[PATCH v2 00/12] mtd: nand_bbt: introduce independent nand BBT

[Ezequiel Garcia]

On 29 December 2015 at 06:35, Boris Brezillon
<boris.brezillon at free-electrons.com> wrote:
> Hi,
>
> On Mon, 28 Dec 2015 17:42:50 -0300
> Ezequiel Garcia <ezequiel at vanguardiasur.com.ar> wrote:
>
>> This is looking a lot better, thanks for the good work!
>>
>> On 15 December 2015 at 02:59, Peter Pan <peterpansjtu at gmail.com> wrote:
>> > Currently nand_bbt.c is tied with struct nand_chip, and it makes other
>> > NAND family chips hard to use nand_bbt.c. Maybe it's the reason why
>> > onenand has own bbt(onenand_bbt.c).
>> >
>> > Separate struct nand_chip from BBT code can make current BBT shareable.
>> > We create struct nand_bbt to take place of nand_chip in nand_bbt.c.
>> > Struct nand_bbt contains all the information BBT needed from outside and
>> > it should be embedded into NAND family chip struct (such as struct nand_chip).
>> > NAND family driver should allocate, initialize and free struct nand_bbt.
>> >
>> > Below is mtd folder structure we want:
>> >         mtd
>> >         ├── Kconfig
>> >         ├── Makefile
>> >         ├── ...
>> >         ├── nand_bbt.c
>>
>> Hm.. I'm not sure about having nand_bbt.c in drivers/mtd.
>> What's wrong with drivers/mtd/nand ?
>
> I haven't reviewed the series yet, but I agree. If the BBT code is only
> meant to be used on NAND based devices, it should probably stay in
> drivers/mtd/nand.
>
>>
>> In fact, I  was thinking we could go further and clean up the directories a bit
>> by separating core code, from controllers code, from SPI NAND code:
>>
>> drivers/mtd/nand/
>> drivers/mtd/nand/controllers
>> drivers/mtd/nand/spi
>>
>> Makes any sense?
>
> Actually I had the secret plan of moving all (raw) NAND controller
> drivers into the drivers/mtd/nand/controllers directory, though this
> was for a different reason: I'd like to create another directory for
> manufacturer specific code in order to support some advanced features
> on NANDs that do not implement (or only partially implement) the ONFI
> standard.
>
> The separation you're talking about here is more related to the
> interface used to communicate with the NAND chip.
>
> How about using the following hierarchy?
>
> drivers/mtd/nand/<nand-core-code>
> drivers/mtd/nand/interfaces/raw/<raw-nand-core-code>
> drivers/mtd/nand/interfaces/raw/controllers/<raw-nand-controller-drivers>
> drivers/mtd/nand/interfaces/spi/<spi-nand-code>
> drivers/mtd/nand/interfaces/onenand/<onenand-code>
> drivers/mtd/nand/chips/<manufacturer-spcific-code>
>
> What do you think?
>

I believe we are bikeshedding here, but what the heck.

That seems too involved. A simpler hierarchy could be clear enough,
and seems to follow what other subsystems do:

drivers/mtd/nand/<all-nand-core-code>
drivers/mtd/nand/raw/<raw-nand-controller-drivers>
drivers/mtd/nand/spi/<spi-nand-code>
drivers/mtd/nand/onenand/<onenand-code>
drivers/mtd/nand/chips/<manufacturer-spcific-code>

-- 
Ezequiel García, VanguardiaSur
www.vanguardiasur.com.ar