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Date:   Wed, 9 Feb 2022 13:47:18 -0800
From:   Keith Busch <kbusch@kernel.org>
To:     nitirawa@codeaurora.org
Cc:     Vidya Sagar <vidyas@nvidia.com>, rafael.j.wysocki@intel.com,
        keith.busch@intel.com, hch@lst.de, bhelgaas@google.com,
        mmaddireddy@nvidia.com, kthota@nvidia.com, sagar.tv@gmail.com,
        linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: Query related to shutting down NVMe during system suspend
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On Thu, Feb 10, 2022 at 02:47:47AM +0530, nitirawa@codeaurora.org wrote:
> IMO, the NVME driver is not associated with any device tree, Instead PCI
> driver is associated with device tree.

That may be good, though: the idle behavior isn't unqiue to nvme. It may
be fine if PCI is the common layer to own this, as long as drivers can
query it.

> So unlike ACPI based platform where we have platform specific DMI matching,
> we don't have equivalent check for DT based platform.

Is there any existing kernel API a driver can call to uniquely identify
such a platform?

> Do we see any concern if we introduce a module param with default not set to
> quick suspend.

As of now, the idea was proposed and was not accepted.