Re: [RFC PATCH 02/16] dt-bindings: display: rockchip: Add EBC binding

From: Andreas Kemnade <andreas@kemnade.info>
To: Samuel Holland <samuel@sholland.org>
Cc: "David Airlie" <airlied@linux.ie>, "Ondřej Jirman" <x@xff.cz>,
	dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
	"Thierry Reding" <thierry.reding@gmail.com>,
	"Michael Riesch" <michael.riesch@wolfvision.net>,
	"Sam Ravnborg" <sam@ravnborg.org>,
	"Nicolas Frattaroli" <frattaroli.nicolas@gmail.com>,
	linux-rockchip@lists.infradead.org,
	"Geert Uytterhoeven" <geert@linux-m68k.org>,
	"Liang Chen" <cl@rock-chips.com>,
	devicetree@vger.kernel.org,
	"Alistair Francis" <alistair@alistair23.me>,
	"Rob Herring" <robh+dt@kernel.org>,
	"Peter Geis" <pgwipeout@gmail.com>,
	linux-arm-kernel@lists.infradead.org,
	"Sandy Huang" <hjc@rock-chips.com>,
	"Thomas Zimmermann" <tzimmermann@suse.de>,
	"Krzysztof Kozlowski" <krzk+dt@kernel.org>
Subject: Re: [RFC PATCH 02/16] dt-bindings: display: rockchip: Add EBC binding
Date: Fri, 15 Apr 2022 13:45:52 +0200	[thread overview]
Message-ID: <20220415134552.182b49a9@aktux> (raw)
In-Reply-To: <d5bb060e-5964-db0d-ca93-5f73ee9277a3@sholland.org>

On Thu, 14 Apr 2022 22:00:09 -0500
Samuel Holland <samuel@sholland.org> wrote:

> Hi Andreas,
> 
> Thanks for the comments.
> 
> On 4/14/22 3:15 AM, Andreas Kemnade wrote:
> > Hi Samuel,
> > 
> > for comparison, here is my submission for the IMX EPDC bindings:
> > 
> > https://lore.kernel.org/linux-devicetree/20220206080016.796556-2-andreas@kemnade.info/
> > 
> > On Wed, 13 Apr 2022 17:19:02 -0500
> > Samuel Holland <samuel@sholland.org> wrote:
> > 
> > [...]
> > we have sy7636a driver in kernel which should be suitable for powering a EPD
> > and temperature measurement. So I would expect that to be   
> >> +  io-channels:
> >> +    maxItems: 1
> >> +    description: I/O channel for panel temperature measurement
> >> +  
> > so how would I reference the hwmon/thermal(-zone) of the sy7636a here?  
> 
> It seems the consensus is to use a thermal zone for panel temperature, so I will
> need to change this.
> 
I am open to anything here as long as it fits together.

> I think it's best to reference the thermal zone by phandle, not by name, even if
> it requires extending the thermal zone API to support this.
> 
maybe referencing the hwmon might be interesting, or we add a hwmon_iio
adaptor. The other way round it is there. The thermal zone stuff is
only needed because hwmon cannot referenced directly.

Regards,
Andreas