Re: [PATCH v2 2/3] spi: Add HiSilicon v3xx SPI NOR flash controller driver

[John Garry]

On 10/01/2020 15:12, Mark Brown wrote:
> On Fri, Jan 10, 2020 at 02:58:54PM +0000, John Garry wrote:
> > On 10/01/2020 14:07, Mark Brown wrote:
> > > On Fri, Jan 10, 2020 at 11:55:37AM +0000, John Garry wrote: >

Hi Mark,

> > > OK, so that's just reusing the DT binding in which case everything
> > > that's valid for the DT binding should also be valid for ACPI - I
> > > thought that actually worked automatically without you having to do
> > > anything in the code but ICBW.
>
> > I thought that it would be improper as we could be mixing ACPI methods to
> > describe the serial bus (SPI Serial Bus Connection Resource Descriptor) and
> > also DT properties which could conflict, like CS active high.
>
> Yes, that's one of the issues with importing bits of DT into ACPI
> unfortunately - you will get conflicts, it's not clear it's a good idea
> to be using PRP0001 for SPI stuff given that there's bus level bindings
> for both ACPI and SPI and they don't line up exactly.

Yeah, I'm not entirely comfortable with this yet.

> > However I do see extra properties than "compatible" being added in DSD for
> > PRP0001:
> > https://patchwork.ozlabs.org/patch/662813/ (see EEPROM part)
>
> > And if we were to do this, I think that we would need to add some
> > device_property_read_u32("spi-rx-bus-width", ...), etc calls in the SPI FW
> > parsing for ACPI path - I couldn't see that.
>
> You'd need parsing code, yes.

I'll continue to check the options.

Thanks,
john