Re: [PATCH 04/10] regulator: of: switch to using class_find_device_by_fwnode()

From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
To: Mark Brown <broonie@kernel.org>
Cc: Andrew Lunn <andrew+netdev@lunn.ch>,
	 "David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	 Jakub Kicinski <kuba@kernel.org>,
	Paolo Abeni <pabeni@redhat.com>, Vinod Koul <vkoul@kernel.org>,
	 Neil Armstrong <neil.armstrong@linaro.org>,
	Liam Girdwood <lgirdwood@gmail.com>, Lee Jones <lee@kernel.org>,
	 Pavel Machek <pavel@kernel.org>, Peter Rosin <peda@axentia.se>,
	Andrew Lunn <andrew@lunn.ch>,
	 Heiner Kallweit <hkallweit1@gmail.com>,
	Russell King <linux@armlinux.org.uk>,
	 Moritz Fischer <mdf@kernel.org>, Xu Yilun <yilun.xu@intel.com>,
	Tom Rix <trix@redhat.com>,
	 Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	 Danilo Krummrich <dakr@kernel.org>,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	 linux-phy@lists.infradead.org, linux-spi@vger.kernel.org,
	linux-leds@vger.kernel.org,  linux-fpga@vger.kernel.org,
	driver-core@lists.linux.dev
Subject: Re: [PATCH 04/10] regulator: of: switch to using class_find_device_by_fwnode()
Date: Mon, 23 Mar 2026 12:41:59 -0700	[thread overview]
Message-ID: <acGWJf1AGXT1xduM@google.com> (raw)
In-Reply-To: <7d46803e-b285-4e9c-8856-10100fa0ea85@sirena.org.uk>

On Mon, Mar 23, 2026 at 07:05:13PM +0000, Mark Brown wrote:
> On Mon, Mar 23, 2026 at 11:28:27AM -0700, Dmitry Torokhov wrote:
> > On Mon, Mar 23, 2026 at 02:00:43PM +0000, Mark Brown wrote:
> 
> > > The regulator API is very deliberately specifically using the OF APIs,
> > > not the ACPI APIs, since ACPI really doesn't want to model regulators.
> 
> > For now? We also have software nodes and maybe we come up with something
> > else in the future...
> 
> > I think we should use firmware-agnostic APIs as much as possible, and
> > only use OF- or ACPI-specific ones when there is no generic equivalent.
> > This makes the code most flexible.
> 
> I think this is a worrying idea for core code like this, we have
> specific firmware bindings for specific firmware interfaces with the
> different interfaces having very different ideas of how things should be
> modelled.  The chances that firmware agnostic code is going to do the
> right thing seem low, and encouraging the use of generic APIs that might
> happen to run OK raises the risk that we'll get firmware vendors relying
> on them and leaving us with a conceptual mishmash to sort through.
> 
> Software nodes are already a bit of a concern here TBH.

Firmware vendors can introduce incompatible DT bindings and have them in
their devices too and we have to deal with that... 

I think if this pushes closer ACPI and OF schemas for at least some
subsystems closer to each other it would not be a bad thing.

Thanks.

-- 
Dmitry