Re: [PATCH v4 7/8] soc: starfive: Add socinfo driver for JHB100 SoC

[Changhuang Liang]

Hi ,Conor

Thanks for the review.

> On Wed, Aug 12, 2026 at 10:37:16AM +0000, Changhuang Liang wrote:
> > Hi, Conor
> >
> > Thanks for the review.
> >
> > > On Tue, Aug 11, 2026 at 05:36:19AM +0000, Changhuang Liang wrote:
> > >
> > > > > On Sat, Aug 08, 2026 at 06:50:53PM -0700, Changhuang Liang wrote:
> > >
> > > > > > +static int __init starfive_socinfo_init(void) {
> > > > > > +	struct soc_device_attribute *attrs;
> > > > > > +	struct soc_device *soc_dev;
> > > > > > +	const char *machine = NULL;
> > > > > > +	struct device_node *np;
> > > > > > +	struct regmap *regmap;
> > > > > > +	char rev_char;
> > > > > > +	u32 rev_id;
> > > > > > +	int ret;
> > > > > > +
> > > > > > +	np = of_find_compatible_node(NULL, NULL,
> > > > > > +"starfive,jhb100-sys0-syscon");
> > > > >
> > > > > Remind me again why this is not just probed as an mfd cell from
> > > > > the syscon driver?
> > > > >
> > > > > (Hint: please put this info in the commit message).
> > > >
> > > > The discussion result with Krzysztof at that time is recorded here:
> > > > https://lore.kernel.org/all/20260405-strong-watchful-marmot-fdfad6
> > > > @quo
> > > > ll/
> > > >
> > > > One register should not be treated as a separate device node.
> > >
> > > That's a different question. In the case of an mfd cell probed from
> > > the syscon driver there would be no devicetree modifications
> > > required compared to what you have now. e.g. sg2044-topsys.c
> >
> > This seems feasible, and I can introduce this modification in the next
> version.
> 
> 
> In fact, you don't even need the mfd cell, because your driver is going to be in
> drivers/soc/starfive anyway? You can just bind directly to the
> sys0 syscon I think.

I suddenly realized that I missed one issue: starfive,jhb100-sys0-syscon is already 
bound to the PLL driver by default, I can't use it to bind another device anymore. 

which is why I used 

np = of_find_compatible_node(NULL, NULL, "starfive,jhb100-sys0-syscon"); 

in jhb100-socinfo.c.

So it seems the MFD cell approach isn't really feasible either?

Best Regards,
Changhuang