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Date:   Tue, 29 Sep 2020 23:34:36 -0700
From:   Nicolin Chen <nicoleotsuka@gmail.com>
To:     Dmitry Osipenko <digetx@gmail.com>
Cc:     thierry.reding@gmail.com, joro@8bytes.org, krzk@kernel.org,
        vdumpa@nvidia.com, jonathanh@nvidia.com,
        linux-tegra@vger.kernel.org, iommu@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 2/3] iommu/tegra-smmu: Rework .probe_device and
 .attach_dev
Message-ID: <20200930063435.GC16460@Asurada-Nvidia>
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 <20200930003013.31289-3-nicoleotsuka@gmail.com>
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 <931eb16b-4529-2c20-c696-c57a9138aded@gmail.com>
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On Wed, Sep 30, 2020 at 08:20:50AM +0300, Dmitry Osipenko wrote:
> 30.09.2020 08:10, Dmitry Osipenko пишет:
> > 30.09.2020 03:30, Nicolin Chen пишет:
> >>  static void tegra_smmu_release_device(struct device *dev)
> > 
> > The tegra_get_memory_controller() uses of_find_device_by_node(), hence
> > tegra_smmu_release_device() should put_device(mc) in order to balance
> > back the refcounting.
> > 
> 
> Actually, the put_device(mc) should be right after
> tegra_get_memory_controller() in tegra_smmu_probe_device() because SMMU
> is a part of MC, hence MC can't just go away.

Hmm..I found that there is no put_device() call in tegra20-devfreq.
Should we just put_device(pdev->dev) in tegra_get_memory_controller?