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 for <linuxppc-dev@lists.ozlabs.org>; Sun, 17 Feb 2013 18:43:31 +1100 (EST)
Date: Sun, 17 Feb 2013 15:43:20 +0800
From: Shawn Guo <shawn.guo@linaro.org>
To: Grant Likely <grant.likely@secretlab.ca>
Subject: Re: [PATCH 2/2] of: use platform_device_add
Message-ID: <20130217074317.GB16632@S2101-09.ap.freescale.net>
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Cc: linux-kernel@vger.kernel.org, Rob Herring <rob.herring@calxeda.com>,
 Jason Gunthorpe <jgunthorpe@obsidianresearch.com>,
 Greg Kroah-Hartman <gregkh@linuxfoundation.org>, linuxppc-dev@lists.ozlabs.org,
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On Sun, Feb 17, 2013 at 11:03:35AM +0800, Shawn Guo wrote:
> On Fri, Jan 18, 2013 at 01:40:00AM +0000, Grant Likely wrote:
> > This allows platform_device_add a chance to call insert_resource on all
> > of the resources from OF. At a minimum this fills in proc/iomem and
> > presumably makes resource tracking and conflict detection work better.
> > However, it has the side effect of moving all OF generated platform
> > devices from /sys/devices to /sys/devices/platform/. It /shouldn't/
> > break userspace because userspace is not supposed to depend on the full
> > path (because userspace always does what it is supposed to, right?).
> > 
> > This may cause breakage if either:
> > 1) any two nodes in a given device tree have overlapping & staggered
> >    regions (ie. 0x80..0xbf and 0xa0..0xdf; where one is not contained
> >    within the other). In this case one of the devices will fail to
> >    register and an exception will be needed in platform_device_add() to
> >    complain but not fail.
> 
> Grant,
> 
> The patch introduce a regression on imx6q boot.

It also breaks all of_amba_device users.

of_amba_device_create() --> amba_device_add() --> request_resource()
and fails.

Shawn