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From: Mark Hasemeyer <markhas@chromium.org>
Date: Thu, 14 Dec 2023 14:04:45 -0700
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Subject: Re: [PATCH v1 2/6] arm: arm64: dts: Enable cros-ec-spi as wake source
To: Rob Herring <robh@kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>, Raul Rangel <rrangel@chromium.org>, 
	Alim Akhtar <alim.akhtar@samsung.com>, Andre Przywara <andre.przywara@arm.com>, 
	Andy Gross <agross@kernel.org>, 
	AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>, Baruch Siach <baruch@tkos.co.il>, 
	Bjorn Andersson <andersson@kernel.org>, Claudiu Beznea <claudiu.beznea@microchip.com>, 
	Conor Dooley <conor+dt@kernel.org>, Heiko Stuebner <heiko@sntech.de>, 
	Jesper Nilsson <jesper.nilsson@axis.com>, Jisheng Zhang <jszhang@kernel.org>, 
	Jonathan Hunter <jonathanh@nvidia.com>, Konrad Dybcio <konrad.dybcio@linaro.org>, 
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>, 
	Matthias Brugger <matthias.bgg@gmail.com>, Michal Simek <michal.simek@amd.com>, 
	Paul Barker <paul.barker@sancloud.com>, Sudeep Holla <sudeep.holla@arm.com>, 
	Thierry Reding <thierry.reding@gmail.com>, cros-qcom-dts-watchers@chromium.org, 
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, 
	linux-arm-msm@vger.kernel.org, linux-mediatek@lists.infradead.org, 
	linux-rockchip@lists.infradead.org, linux-samsung-soc@vger.kernel.org, 
	linux-tegra@vger.kernel.org
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> If a device knows it is wakeup capable, why do you need a property too?

I'm referencing:
https://www.kernel.org/doc/Documentation/devicetree/bindings/power/wakeup-source.txt
"Nodes that describe devices which has wakeup capability must contain
an "wakeup-source" boolean property."

Currently the driver assumes the device is wake capable without
parsing the device tree, which is an incorrect assumption as wake
capability should not be enabled on some cros_ec systems.

> I haven't looked closely enough, but it smells like after patch 6, these
> properties would be required for wakeup? That would be an ABI break.

Agreed. In this case, the driver is a ChromeOS related driver and DTS
is built from source for each OS update.
For more context, I will make sure to CC you (and everyone else) and
include a cover letter in the next series version.