From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>
Subject: Re: [PATCHv3 01/19] [HACK] of: dev_node has struct device pointer
Date: Fri, 01 Nov 2013 15:44:29 -0600
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To: Hiroshi Doyu <hdoyu-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
Cc: "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" <devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Stephen Warren <swarren-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>, "rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org" <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>, "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" <linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, "iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org" <iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>, "thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org" <thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, "grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org" <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
List-Id: linux-tegra@vger.kernel.org

On 11/01/2013 12:49 AM, Hiroshi Doyu wrote:
> On Thu, 31 Oct 2013 18:53:22 +0100
> Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org> wrote:
> ...
>> We're talking about memory-mapped on-SoC devices here, that generally
>> only exist inside Tegra SoCs.
>>
>> Even ignoring that (i.e. expanding the argument to arbitrary modules),
>> having drivers that perform bus-master transactions call a function
>> of_iommu_attach() or similar, which does nothing if the device isn't
>> behind an IOMMU but otherwise does whatever is required, seems like it
>> isn't much of an imposition.
> 
> Where do you expect of_iommu_attach() to be called?
> I thought something below:

> diff --git a/drivers/base/dd.c b/drivers/base/dd.c

> @@ -278,6 +278,10 @@ static int really_probe(struct device *dev, struct device_driver *drv)
>  	if (ret)
>  		goto probe_failed;
>  
> +	ret = of_iommu_attach(dev);
> +	if (ret)
> +		goto probe_failed;

That sounds reasonable.