linux-kernel - Re: [PATCH 3/6] dt-bindings: HID: i2c-hid: elan: add 'no-reset-on-power-off' property

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <Zjo7CuT7UyQC57Rr@hovoldconsulting.com>
Date: Tue, 7 May 2024 16:30:34 +0200
From: Johan Hovold <johan@...nel.org>
To: Linus Walleij <linus.walleij@...aro.org>
Cc: Johan Hovold <johan+linaro@...nel.org>, Jiri Kosina <jikos@...nel.org>,
	Benjamin Tissoires <benjamin.tissoires@...hat.com>,
	Dmitry Torokhov <dmitry.torokhov@...il.com>,
	Rob Herring <robh@...nel.org>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>,
	Conor Dooley <conor+dt@...nel.org>,
	Bjorn Andersson <andersson@...nel.org>,
	Konrad Dybcio <konrad.dybcio@...aro.org>,
	Douglas Anderson <dianders@...omium.org>,
	linux-input@...r.kernel.org, devicetree@...r.kernel.org,
	linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/6] dt-bindings: HID: i2c-hid: elan: add
 'no-reset-on-power-off' property

On Mon, May 06, 2024 at 08:29:40AM +0200, Linus Walleij wrote:

> +  no-reset-on-power-off:
> +    type: boolean
> +    description:
> +      Reset line is wired so that it can be left deasserted when the power
> +      supply is off.
> 
> To be nitpicky: *should* be left deasserted rather than *can* be left
> deasserted, right? If the behaviour is desirable but not strictly
> required.

I considered that too, but settled on the above description as it is
pure hardware description and leaving the decision to act on it up to
the OS (e.g. if support is implemented).

On the other hand, the "should" is already implied by the property name
so perhaps there's no reason not to include it also in the description:

+  no-reset-on-power-off:
+    type: boolean
+    description:
+      Reset line is wired so that it can (and should) be left
+      deasserted when the power supply is off.

And "should" (unlike "shall") still leaves room for an OS to ignore it
at the cost of increased power consumption.

Johan