Re: [PATCH 1/3] iommu: of: Fix check for returning EPROBE_DEFER

From: Sricharan R <sricharan-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>
To: Bjorn Helgaas <helgaas-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
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Subject: Re: [PATCH 1/3] iommu: of: Fix check for returning EPROBE_DEFER
Date: Thu, 18 May 2017 14:33:57 +0530	[thread overview]
Message-ID: <1c306cf1-f7fb-87b1-1fef-3b08aea04560@codeaurora.org> (raw)
In-Reply-To: <20170517170430.GD31462-1RhO1Y9PlrlHTL0Zs8A6p5iNqAH0jzoTYJqu5kTmcBRl57MIdRCFDg@public.gmane.org>

Hi Bjorn,

On 5/17/2017 10:34 PM, Bjorn Helgaas wrote:
> On Wed, May 17, 2017 at 05:00:07PM +0530, Sricharan R wrote:
>> Now with iommu probe deferral, we return -EPROBE_DEFER
>> for master's that are connected to an iommu which is not
> 
> s/master's/masters/
> 
> s/iommu/IOMMU/ in your English text (changelogs and comments).  That seems
> to be the convention, based on "git log drivers/iommu/of_iommu.c"
> 

ok, will correct those.

Regards,
 Sricharan

>> probed yet, but going to get probed, so that we can attach
>> the correct dma_ops. So while trying to defer the probe of
>> the master, check if the of_iommu node that it is connected
>> to is marked in DT as 'status=disabled', then the iommu is never
>> is going to get probed. So simply return NULL and let the master
>> work without an iommu.
>>
>> Fixes: 7b07cbefb68d ("iommu: of: Handle IOMMU lookup failure with deferred probing or error")
>> Signed-off-by: Sricharan R <sricharan-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>
>> Reported-by: Geert Uytterhoeven <geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org>
>> Tested-by: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
>> Tested-by: Magnus Damn <magnus.damn-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>> Acked-by: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
>> ---
>>  drivers/iommu/of_iommu.c | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
>> index 9f44ee8..e6e9bec 100644
>> --- a/drivers/iommu/of_iommu.c
>> +++ b/drivers/iommu/of_iommu.c
>> @@ -118,6 +118,7 @@ static bool of_iommu_driver_present(struct device_node *np)
>>  
>>  	ops = iommu_ops_from_fwnode(fwnode);
>>  	if ((ops && !ops->of_xlate) ||
>> +	    !of_device_is_available(iommu_spec->np) ||
>>  	    (!ops && !of_iommu_driver_present(iommu_spec->np)))
>>  		return NULL;
>>  
>> -- 
>> QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
>>
>>
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-- 
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