Re: [PATCH v1 1/2] dt-bindings: display: panel: raspberrypi: Add compatible property for waveshare 7inch touchscreen panel

From: Conor Dooley <conor.dooley@microchip.com>
To: Shengyang Chen <shengyang.chen@starfivetech.com>
Cc: Conor Dooley <conor@kernel.org>, <devicetree@vger.kernel.org>,
	<dri-devel@lists.freedesktop.org>, <neil.armstrong@linaro.org>,
	<quic_jesszhan@quicinc.com>, <sam@ravnborg.org>,
	<airlied@gmail.com>, <daniel@ffwll.ch>,
	<maarten.lankhorst@linux.intel.com>, <mripard@kernel.org>,
	<tzimmermann@suse.de>, <robh+dt@kernel.org>,
	<krzysztof.kozlowski+dt@linaro.org>, <conor+dt@kernel.org>,
	<florian.fainelli@broadcom.com>,
	<bcm-kernel-feedback-list@broadcom.com>, <eric@anholt.net>,
	<thierry.reding@gmail.com>, <changhuang.liang@starfivetech.com>,
	<keith.zhao@starfivetech.com>, <jack.zhu@starfivetech.com>,
	<linux-rpi-kernel@lists.infradead.org>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v1 1/2] dt-bindings: display: panel: raspberrypi: Add compatible property for waveshare 7inch touchscreen panel
Date: Thu, 7 Dec 2023 09:34:59 +0000	[thread overview]
Message-ID: <20231207-dullness-deprive-ece2d47ff69d@wendy> (raw)
In-Reply-To: <53b992e8-1b36-4540-a993-fde8e550faf9@starfivetech.com>

[-- Attachment #1.1: Type: text/plain, Size: 2371 bytes --]

On Thu, Dec 07, 2023 at 11:48:56AM +0800, Shengyang Chen wrote:
> Hi, Conor
> 
> thanks for comment
> 
> On 2023/12/6 23:40, Conor Dooley wrote:
> > On Wed, Dec 06, 2023 at 05:43:48PM +0800, Shengyang Chen wrote:
> >> Hi, Conor
> >> 
> >> On 2023/11/24 20:31, Conor Dooley wrote:
> >> > On Fri, Nov 24, 2023 at 06:44:50PM +0800, Shengyang Chen wrote:
> >> >> The waveshare 7inch touchscreen panel is a kind of raspberrypi pi
> >> >> panel
> >> > 
> >> > Can you be more specific about what "is a kind of rpi panel" means?
> >> > Are they using identical chips as controllers or something like that?
> >> > 
> >> 
> >> Wareshare panel has same i2c slave address and registers address with 
> >> the original raspberry pi panel. They both use Atmel firmware and they
> >> got same reg id. It can be operated by using the driver of raspberry pi driver
> >> after some change of the code. So I suppose it may be a kind of raspberry pi panel 
> >> and discribe it in this way. It's my own judgement. Sorry about that.
> >> Maybe just like Dave said, It cloned the behaviour of the raspberri pi panel.
> >> I will change the discribtion in next version to not make other confused.
> >> 
> >> By the way, we will try Stefan's method before next version. 
> >> The method we used in this patch may be abandoned if Stefan's method is verified in our platform.
> >> At that time yaml may also be changed to fit new method.
> > 
> > I don't know what Stefan's approach is, but I do not think that a
> > bindings patch should be dropped. The waveshare might be a clone, but it
> > is a distinct device. If the same driver can control both, then the
> > compatible setups that should be permitted are:
> > compatible = "raspberrypi,7inch-touchscreen-panel";
> > and
> > compatible = "waveshare,7inch-touchscreen-panel", "raspberrypi,7inch-touchscreen-panel";

> If we use Stenfan's method, we can reuse the code of panel-simple.c
> we may submit our patch to
> /Documentation/devicetree/bindings/display/panel/panel-simple.yaml
> /drivers/gpu/drm/panel/panel-simple.c
> as a new panel porting. That may less confuse.

As long as you provide a specific compatible, and not re-use the rpi
one, that's fine. It just sounded like you were intending to reuse that
here, but from this message it seems like I misunderstood.

Thanks,
Conor.

[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

[-- Attachment #2: Type: text/plain, Size: 176 bytes --]

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel