[PATCH v2 3/6] spi: dw: Add Microchip Sparx5 support

Mark Brown broonie at kernel.org
Mon Jun 22 08:17:06 EDT 2020

On Mon, Jun 22, 2020 at 12:46:33PM +0200, Lars Povlsen wrote:
> On Fri, Jun 19, 2020 at 01:31:18PM +0200, Lars Povlsen wrote:

> >> +	if (!nEnable) {
> >> +		/* Ensure CS toggles, so start off all disabled */
> >> +		regmap_write(dwsmscc->syscon, SPARX5_FORCE_VAL, ~0);
> >> +		/* CS override drive enable */
> >> +		regmap_write(dwsmscc->syscon, SPARX5_FORCE_ENA, 1);

> >This should just be setting the value to whatever the core asked for it
> >to be set to, the driver adding extra toggles is likely to disrupt
> >things.

> I will have a look at this again. But it was added for a reason. The
> issue is that we have two different busses in front of the controller,
> so we might need more settle time when switching interface.

If there's a mux that needs to be handled specially that mux should be
described in DT on the relevant boards, there shouldn't just be
something hard coded in the controller driver.

BTW please do not CC subsystem patches to soc at kernel.org unless there's
a specific reason to do so - there's no need for it, these patches won't
get merged via there unless something is going wrong.  Generally the
subsystem maintainers take patches for a given subsystem.
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