linux-kernel - Re: [PATCH v1 0/2] userspace-consumer: adding is

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

Message-ID: <CAOC4094v+MyrWgbkDJZ5KJhzuTmmgAuS-XacbFt5jHK3aYtOrg@mail.gmail.com>
Date: Wed, 28 May 2025 11:32:19 -0700
From: Daniel Okazaki <dtokazaki@...gle.com>
To: Mark Brown <broonie@...nel.org>
Cc: Liam Girdwood <lgirdwood@...il.com>, Rob Herring <robh@...nel.org>, 
	Krzysztof Kozlowski <krzk+dt@...nel.org>, Conor Dooley <conor+dt@...nel.org>, 
	Zev Weiss <zev@...ilderbeest.net>, kernel-team@...roid.com, 
	linux-kernel@...r.kernel.org, devicetree@...r.kernel.org
Subject: Re: [PATCH v1 0/2] userspace-consumer: adding is_shared flag

> What is the use case here?
The request is for a regulator to be controlled by two different
subsystems. One is a userspace HAL and the other is
a kernel driver.

Alternatively I could expose sysfs nodes in the kernel driver
for the HAL layer to connect to, but it would add coupling
between userspace and the kernel driver that might not
otherwise be necessary. The userspace regulator driver
would add some abstraction between the actual hardware
and the sysfs interface.


On Wed, May 28, 2025 at 11:16 AM Mark Brown <broonie@...nel.org> wrote:
>
> On Wed, May 28, 2025 at 05:44:23PM +0000, Daniel Okazaki wrote:
>
> > Currently this userspace regulator driver requires exclusive control
> > of the regulator to operate. This patch adds an optional flag to
> > remove that constraint, and allow the regulator to be shared by other
> > modules. This allows for userspace to share control over a regulator
> > with kernel space.
>
> What is the use case here?  This is a debug tool intended mainly for
> when you're developing a regulator driver and have something like a
> development board with no consumers at all.