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Message-ID: <2d48e460-e46e-431f-bd7b-e34ebe73a40c@starfivetech.com>
Date:   Wed, 6 Dec 2023 17:43:48 +0800
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Subject: Re: [PATCH v1 1/2] dt-bindings: display: panel: raspberrypi: Add
 compatible property for waveshare 7inch touchscreen panel
Content-Language: en-US
To:     Conor Dooley <conor@kernel.org>
CC:     <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>,
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        <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>,
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References: <20231124104451.44271-1-shengyang.chen@starfivetech.com>
 <20231124104451.44271-2-shengyang.chen@starfivetech.com>
 <20231124-lesser-sinister-7f9cd7b80e35@spud>
From:   Shengyang Chen <shengyang.chen@starfivetech.com>
In-Reply-To: <20231124-lesser-sinister-7f9cd7b80e35@spud>
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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.


>> and it can be drived by panel-raspberrypi-touchscreen.c.
>> Add compatible property for it.
>> 
>> Signed-off-by: Keith Zhao <keith.zhao@starfivetech.com>
>> Signed-off-by: Shengyang Chen <shengyang.chen@starfivetech.com>
>> ---
>>  .../bindings/display/panel/raspberrypi,7inch-touchscreen.yaml | 4 +++-
>>  1 file changed, 3 insertions(+), 1 deletion(-)
>> 
>> diff --git a/Documentation/devicetree/bindings/display/panel/raspberrypi,7inch-touchscreen.yaml b/Documentation/devicetree/bindings/display/panel/raspberrypi,7inch-touchscreen.yaml
>> index 22a083f7bc8e..e4e6cb4d4e5b 100644
>> --- a/Documentation/devicetree/bindings/display/panel/raspberrypi,7inch-touchscreen.yaml
>> +++ b/Documentation/devicetree/bindings/display/panel/raspberrypi,7inch-touchscreen.yaml
>> @@ -22,7 +22,9 @@ description: |+
>>  
>>  properties:
>>    compatible:
>> -    const: raspberrypi,7inch-touchscreen-panel
>> +    enum:
>> +      - raspberrypi,7inch-touchscreen-panel
>> +      - waveshare,7inch-touchscreen-panel
>>  
>>    reg:
>>      const: 0x45
>> -- 
>> 2.17.1
>> 


thanks.

Best Regards,
Shengyang