From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
To: Maurizio Casciano <mauriziocasciano7@gmail.com>
Cc: linux-input@vger.kernel.org, Liam Girdwood <lgirdwood@gmail.com>,
Mark Brown <broonie@kernel.org>,
David Heidelberg <david@ixit.cz>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] Input: drv260x: Make vbat supply optional
Date: Thu, 27 Aug 2026 03:54:09 -0700 [thread overview]
Message-ID: <apAWXyPRtSe0Uk9_@google.com> (raw)
In-Reply-To: <20260826132211.3341936-2-mauriziocasciano7@gmail.com>
Hi Maurizio,
On Wed, Aug 26, 2026 at 03:22:10PM +0200, Maurizio Casciano wrote:
> The Lenovo Yoga Book YB1-X91L firmware instantiates two DRV2604
> ACPI devices, but does not describe a software-controllable vbat supply
> for either device. The generic regulator lookup therefore creates a
> dummy supply.
Yes, that is how most of the drivers handle supplies on ACPI systems.
>
> Use the optional regulator lookup and skip regulator operations when no
> supply is described. Systems which provide vbat retain the existing
> enable, managed-disable, suspend, resume, and error-unwind behavior.
regulator_get_optional() should only be used in cases where supply can
be left unconnected in normal use. This is different from this case
where supply *is connected* but it is managed by ACPI/board firmware.
IOW this patch is not needed.
Thanks.
--
Dmitry
next prev parent reply other threads:[~2026-08-27 10:54 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-26 13:22 [PATCH 0/2] Input: Add ACPI support needed by Yoga Book DRV2604 Maurizio Casciano
2026-08-26 13:22 ` [PATCH 1/2] Input: drv260x: Make vbat supply optional Maurizio Casciano
2026-08-26 13:36 ` sashiko-bot
2026-08-27 10:54 ` Dmitry Torokhov [this message]
2026-08-27 18:15 ` Maurizio Casciano
2026-08-26 13:22 ` [PATCH 2/2] Input: drv260x: Map ACPI enable GPIO Maurizio Casciano
2026-08-26 13:37 ` sashiko-bot
2026-08-27 10:58 ` Dmitry Torokhov
2026-08-27 18:15 ` Maurizio Casciano
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