Re: [PATCH v2 3/3] dt-bindings: mtd: Document use of nvmem-partitions compatible

On 05.03.2021 23:23, Rob Herring wrote:

On Wed, Mar 03, 2021 at 11:01:55AM +0100, Rafał Miłecki wrote:

quoted

[Rob: please advise]

On 16.02.2021 22:26, Ansuel Smith wrote:

quoted

Document nvmem-partitions compatible used to treat mtd partitions as a
nvmem provider.

Until now we were using "compatible" string in partition node only for
parsers (looking for subpartitions). We need to think if this change can
break anything from DT / Linux perspective.

Compatible strings should be unique, so there is no risk of conflict
between NVMEM and parsers.

Now: can we ever need mtd partition to:
1. Contain subpartitions
2. Provide NVMEM
at the same time?

Let's say:

partition@0 {
	compatible = "vendor,dynamic-firmware-partitions", "nvmem-partitions";

I think you'd want the "vendor,dynamic-firmware-partitions" parser/code
to serve up any nvmem regions. Whether you have a fallback here depends
if an OS could make use of the regions knowing nothing about
"vendor,dynamic-firmware-partitions".

Perfect! I didn't think that driver handling
"vendor,dynamic-firmware-partitions" may also take care of NVMEM.

Thank you.