On Thu, May 12, 2022 at 10:49:39AM +0100, Lee Jones wrote:

On Tue, 10 May 2022, Colin Foster wrote:

quoted

On Tue, May 10, 2022 at 04:32:26PM +0100, Lee Jones wrote:

quoted

On Mon, 09 May 2022, Vladimir Oltean wrote:

quoted

On Mon, May 09, 2022 at 04:49:22PM -0700, Colin Foster wrote:

quoted

quoted

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+struct regmap *ocelot_init_regmap_from_resource(struct device *child,
+						const struct resource *res)
+{
+	struct device *dev = child->parent;
+
+	return ocelot_spi_devm_init_regmap(dev, child, res);

So much for being bus-agnostic :-/
Maybe get the struct ocelot_ddata and call ocelot_spi_devm_init_regmap()
via a function pointer which is populated by ocelot-spi.c? If you do
that don't forget to clean up drivers/mfd/ocelot.h of SPI specific stuff.

That was my initial design. "core" was calling into "spi" exclusively
via function pointers.

The request was "Please find a clearer way to do this without function
pointers"

https://lore.kernel.org/netdev/Ydwju35sN9QJqJ%2FP@google.com/ (local)

Yeah, I'm not sure what Lee was looking for, either. In any case I agree
with the comment that you aren't configuring a bus. In this context it
seems more appropriate to call this function pointer "init_regmap", with
different implementations per transport.

FWIW, I'm still against using function pointers for this.

What about making ocelot_init_regmap_from_resource() an inline
function and pushing it into one of the header files?

[As an aside, you don't need to pass both dev (parent) and child]

I see your point. This wasn't always the case, since ocelot-core prior
to v8 would call ocelot_spi_devm_init_regmap. Since this was changed,
the "dev, dev" part can all be handled internally. That's nice.

quoted

In there you could simply do:

inline struct regmap *ocelot_init_regmap_from_resource(struct device *dev,
						       const struct resource *res)
{
	if (dev_get_drvdata(dev->parent)->spi)
		return ocelot_spi_devm_init_regmap(dev, res);

	return NULL;
}

If I do this, won't I have to declare ocelot_spi_devm_init_regmap in a
larger scope (include/soc/mscc/ocelot.h)? I like the idea of keeping it
more hidden inside drivers/mfd/ocelot.h, assuming I can't keep it
enclosed in drivers/mfd/ocelot-spi.c entirely.

Yes, it will have the same scope as ocelot_init_regmap_from_resource().

Have you considered include/linux/mfd?

I hadn't, but that seems to make sense here. I'll try to get all the
suggestions implemented in the next few days and send something back
out.

Thanks for the feedback!

-- 
Lee Jones [李琼斯]
Principal Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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