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Wysocki" Cc: linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-tegra@vger.kernel.org References: Content-Language: en-US From: Oliver Neukum In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 03.07.25 12:08, Thierry Reding wrote: > Any thoughts on how to solve this? Is the pm_runtime_{put,get}_sync() > method acceptable? If not, are there other alternatives to achieve the > same thing that I'm not aware of? Would it be useful to add a new set of > APIs to force devices into an idle state (which could be semantically > different from runtime suspend)? Or is this all too specific for any > kind of generic API? Basically what you need is what happens when the system prepares to do a snapshot for S4. However, if you just perform FREEZE and then THAW, devices will assume that user space has been frozen. You need a way to substitute for that assumption. Runtime power management is unlikely to be a fruitful approach to your needs. HTH Oliver