Re: [Linux-stm32] [PATCH V4] nvmem: add explicit config option to read old syntax fixed OF cells

[Rafał Miłecki]

Hi Ahmad,

On 2023-07-18 11:08, Ahmad Fatoum wrote:
> > diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
> > index 60670b2f70b9..334adbae3690 100644
> > --- a/drivers/mtd/mtdcore.c
> > +++ b/drivers/mtd/mtdcore.c
> > @@ -522,6 +522,7 @@ static int mtd_nvmem_add(struct mtd_info *mtd)
> >  	config.dev = &mtd->dev;
> >  	config.name = dev_name(&mtd->dev);
> >  	config.owner = THIS_MODULE;
> > +	config.add_legacy_fixed_of_cells = of_device_is_compatible(node, 
> > "nvmem-cells");
>
> How does the new binding look like in this situation?
>
> Before it was:
>
> &{flash/partitions} {
> 	compatible = "fixed-partitions";
> 	#address-cells = <1>;
> 	#size-cells = <1>;
>
> 	partition@0 {
> 		compatible = "nvmem-cells";
> 		reg = <0 0x100>;
> 		#address-cells = <1>;
> 		#size-cells = <1>;
>
> 		calib@1 {
> 			reg = <1 1>;
> 		};
> 	}
> };
>
> It it now the same, but s/"nvmem-cells"/"fixed-layout"/ ?

Please take a look at those commits and examples:

bd912c991d2e ("dt-bindings: nvmem: layouts: add fixed-layout")
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=bd912c991d2ef079a32558f057b8663bcf1fb6fc

fa7fbe53ecdc ("dt-bindings: nvmem: convert base example to use NVMEM 
fixed cells layout")
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=fa7fbe53ecdc4e7d549a9f73a40e257b0046b4b9


Basically you need a "nvmem-layout" node with:
compatible = "fixed-layout";

So in your case that would be:

&{flash/partitions} {
	compatible = "fixed-partitions";

	partition@0 {
		reg = <0 0x100>;

		nvmem-layout {
			compatible = "fixed-layout";
			#address-cells = <1>;
			#size-cells = <1>;

			calib@1 {
				reg = <1 1>;
			};
		};
	}
};