Re: [PATCH 3/9] powerpc/rcpm: add RCPM driver

[Scott Wood <scottwood@freescale.com>]

On Wed, 2014-03-12 at 11:59 +0800, Chenhui Zhao wrote:
> On Tue, Mar 11, 2014 at 06:42:51PM -0500, Scott Wood wrote:
> > On Fri, 2014-03-07 at 12:57 +0800, Chenhui Zhao wrote:
> > > +int fsl_rcpm_init(void)
> > > +{
> > > +	struct device_node *np;
> > > +
> > > +	np = of_find_compatible_node(NULL, NULL, "fsl,qoriq-rcpm-2.0");
> > > +	if (np) {
> > > +		rcpm_v2_regs = of_iomap(np, 0);
> > > +		of_node_put(np);
> > > +		if (!rcpm_v2_regs)
> > > +			return -ENOMEM;
> > > +
> > > +		qoriq_pm_ops = &qoriq_rcpm_v2_ops;
> > > +
> > > +	} else {
> > > +		np = of_find_compatible_node(NULL, NULL, "fsl,qoriq-rcpm-1.0");
> > > +		if (np) {
> > > +			rcpm_v1_regs = of_iomap(np, 0);
> > > +			of_node_put(np);
> > > +			if (!rcpm_v1_regs)
> > > +				return -ENOMEM;
> > > +
> > > +			qoriq_pm_ops = &qoriq_rcpm_v1_ops;
> > > +
> > > +		} else {
> > > +			pr_err("%s: can't find the rcpm node.\n", __func__);
> > > +			return -EINVAL;
> > > +		}
> > > +	}
> > > +
> > > +	return 0;
> > > +}
> > 
> > Why isn't this a proper platform driver?
> > 
> > -Scott
> 
> The RCPM is not a single function IP block, instead it is a collection
> of device run control and power management. It would be called by other
> drivers and functions. For example, the callback .freeze_time_base()
> need to be called at early stage of kernel init. Therefore, it would be
> better to init it at early stage.

OK, but consider using of_find_matching_node_and_match().

-Scott