From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Subject: Re: [RFC PATCH 1/2] ACPI / PNP: Don't add "enumeration_by_parent"
 devices
Date: Fri, 20 Apr 2018 16:52:22 +0300
Message-ID: <20180420135222.GY2173@lahna.fi.intel.com>
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To: John Garry <john.garry@huawei.com>
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On Fri, Apr 20, 2018 at 02:24:18PM +0100, John Garry wrote:
> Hi Mika,
> 
> On 20/04/2018 14:07, Mika Westerberg wrote:
> > On Fri, Apr 20, 2018 at 06:07:25PM +0800, John Garry wrote:
> > > +	} else {
> > > +		device->driver_data = dev;
> > 
> > I think this deserves a comment explaining why we (ab)use driver_data
> > like this.
> 
> Sure, could add. I didn't see any other way for the acpi_device structure to
> reference the derived PNP device.
> 
> TBH, This overall approach is not good since we are creating the PNP device
> in the scan, and then leaving the device in limbo, waiting for the parent to
> add it, if at all. There's no rule for this.
> 
> So I'm looking for ideas on how to improve this.

One idea is to make pnpacpi_add_device() available outside of PNP and
call it directly (or some variation) in hisi_lpc.c when it walks over
its children.