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Subject: Re: [PATCH v4 1/3] iommu/tegra-smmu: Use fwspec in
 tegra_smmu_(de)attach_dev
To:     Nicolin Chen <nicoleotsuka@gmail.com>, thierry.reding@gmail.com,
        joro@8bytes.org
Cc:     vdumpa@nvidia.com, jonathanh@nvidia.com,
        linux-tegra@vger.kernel.org, iommu@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org
References: <20201002060807.32138-1-nicoleotsuka@gmail.com>
 <20201002060807.32138-2-nicoleotsuka@gmail.com>
From:   Dmitry Osipenko <digetx@gmail.com>
Message-ID: <90e4709c-1684-a280-92dc-0a4de2e4457b@gmail.com>
Date:   Fri, 2 Oct 2020 17:26:13 +0300
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02.10.2020 09:08, Nicolin Chen пишет:
>  static void tegra_smmu_detach_dev(struct iommu_domain *domain, struct device *dev)
>  {
> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
>  	struct tegra_smmu_as *as = to_smmu_as(domain);
> -	struct device_node *np = dev->of_node;
>  	struct tegra_smmu *smmu = as->smmu;
> -	struct of_phandle_args args;
>  	unsigned int index = 0;
>  
> -	while (!of_parse_phandle_with_args(np, "iommus", "#iommu-cells", index,
> -					   &args)) {
> -		unsigned int swgroup = args.args[0];
> -
> -		if (args.np != smmu->dev->of_node) {
> -			of_node_put(args.np);
> -			continue;
> -		}
> -
> -		of_node_put(args.np);
> +	if (!fwspec)
> +		return;

When !fwspec could be true?