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Date:   Wed, 3 Feb 2021 17:12:19 +0000
From:   Christoph Hellwig <hch@infradead.org>
To:     Ben Widawsky <ben.widawsky@intel.com>
Cc:     Christoph Hellwig <hch@infradead.org>, linux-cxl@vger.kernel.org,
        linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-nvdimm@lists.01.org, linux-pci@vger.kernel.org,
        Bjorn Helgaas <helgaas@kernel.org>,
        Chris Browy <cbrowy@avery-design.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Ira Weiny <ira.weiny@intel.com>,
        Jon Masters <jcm@jonmasters.org>,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        Rafael Wysocki <rafael.j.wysocki@intel.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Vishal Verma <vishal.l.verma@intel.com>,
        daniel.lll@alibaba-inc.com,
        "John Groves (jgroves)" <jgroves@micron.com>,
        "Kelley, Sean V" <sean.v.kelley@intel.com>
Subject: Re: [PATCH 02/14] cxl/mem: Map memory device registers
Message-ID: <20210203171219.GA4104698@infradead.org>
References: <20210130002438.1872527-1-ben.widawsky@intel.com>
 <20210130002438.1872527-3-ben.widawsky@intel.com>
 <20210202180441.GC3708021@infradead.org>
 <20210202183151.7kwruvip7nshqsc4@intel.com>
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On Tue, Feb 02, 2021 at 10:31:51AM -0800, Ben Widawsky wrote:
> > > +		if (reg_type == CXL_REGLOC_RBI_MEMDEV) {
> > > +			rc = 0;
> > > +			cxlm = cxl_mem_create(pdev, reg_lo, reg_hi);
> > > +			if (!cxlm)
> > > +				rc = -ENODEV;
> > > +			break;
> > 
> > And given that we're going to grow more types eventually, why not start
> > out with a switch here?  Also why return the structure when nothing
> > uses it?
> 
>  We've (Intel) already started working on the libnvdimm integration which does
>  change this around a bit. In order to go with what's best tested though, I've
>  chosen to use this as is for merge. Many different people not just in Intel
>  have tested these codepaths. The resulting code moves the check on register
>  type out of this function entirely.
> 
>  If you'd like me to make it a switch, I can, but it's going to be extracted
>  later anyway.

This was just a suggestion.  No hard feelings, it's just that the code
looks a little odd to me.