Re: [PATCH] arm64: dts: imx93-9x9-qsb: Add tianma,tm050rdh03 panel

[Liu Ying <victor.liu@nxp.com>]

On Wed, Apr 08, 2026 at 06:50:31AM -0400, Frank Li wrote:
> On Wed, Apr 08, 2026 at 04:40:37PM +0800, Liu Ying wrote:
>> On Wed, Apr 08, 2026 at 04:28:40AM -0400, Frank Li wrote:
> ...
>>>>>>>
>>>>>>> Is it possible to appply this overlay file and kd50g21-40nt-a1 overlay file
>>>>>>>
>>>>>>> to imx93-9x9-qsb.dtb, so needn't create dtsi.
>>>>>>
>>>>>> I'm sorry, I don't get your question here.
>>>>>> Anyway, the DT overlays are needed, because the 40-pin EXP/PRI interface on
>>>>>> the i.MX93 9x9 QSB board can not only connect to a DPI panel adapter board
>>>>>> but also to an audio hat[2], and maybe more.  The newly introduced .dtsi
>>>>>> file just aims to avoid duplicated code.
>>>>>
>>>>> My means apply two overlay files to dtb
>>>>>
>>>>> imx93-9x9-qsb-tianma-tm050rdh03-dtbs += imx93-9x9-qsb.dtb imx93-9x9-qsb-ontat-kd50g21-40nt-a1.dtbo imx93-9x9-qsb-tianma-tm050rdh03.dtbo
>>
>> This ...
>>
>>>>>
>>>>> In imx93-9x9-qsb-tianma-tm050rdh03.dtbo, only include
>>>>> &{/} {
>>>>> 	panel {
>>>>> 		compatible = "tianma,tm050rdh03";
>>>>> 		enable-gpios = <&pcal6524 8 GPIO_ACTIVE_HIGH>;
>>>>> 	};
>>>>> };
>>>>
>>>> If an user wants to use imx93-9x9-qsb.dtb and the DT overlay blob
>>>> imx93-9x9-qsb-tianma-tm050rdh03.dtbo to enable the tianma,tm050rdh03
>>>> DPI panel, then it won't work unless the user also apply
>>>> imx93-9x9-qsb-ontat-kd50g21-40nt-a1.dtbo, right?
>>>>
>>>>>
>>>
>>> Yes, imx93-9x9-qsb-tianma-tm050rdh03.dtb already created, which already
>>> applied both overlay file.
>>
>> .... indicates that imx93-9x9-qsb-tianma-tm050rdh03.dtb is generated by
>> applying both imx93-9x9-qsb-ontat-kd50g21-40nt-a1.dtbo and
>> imx93-9x9-qsb-tianma-tm050rdh03.dtbo to imx93-9x9-qsb.dtb.
>> While, imx93-9x9-qsb-tianma-tm050rdh03.dtbo(a DT overlay blob) just contains
>> the panel node, which means that an user __cannot_ enable the tianma,tm050rdh03
>> DPI panel by only applying it to imx93-9x9-qsb.dtb, unless the user also
>> applies imx93-9x9-qsb-ontat-kd50g21-40nt-a1.dtbo.  That's why the .dtsi
>> file is needed.
> 
> what's problem if we require user do that? Makefile already create finial
> imx93-9x9-qsb-tianma-tm050rdh03.dtb.

The problem is that the user would apply imx93-9x9-qsb-tianma-tm050rdh03.dtbo
to imx93-9x9-qsb.dtb to enable the tianma,tm050rdh03 DPI panel, say in the
U-boot stage with the 'fdt' command, which is fairly a typical usecase, just
like the user would apply imx93-9x9-qsb-ontat-kd50g21-40nt-a1.dtbo to
imx93-9x9-qsb.dtb to enable the ontat,kd50g21-40nt-a1 DPI panel.  We cannot
ask the user to additionally apply imx93-9x9-qsb-ontat-kd50g21-40nt-a1.dtbo
to enable the tianma,tm050rdh03 DPI panel, because that's very confusing.

Note that imx93-9x9-qsb-tianma-tm050rdh03.dtb certainly can be used to
enable the tianma,tm050rdh03 DPI panel, but in addition to that,
imx93-9x9-qsb.dtb + imx93-9x9-qsb-tianma-tm050rdh03.dtbo can also be
used to enable the panel.

> 
> Any user really apply dtso manaully without use kernel's Makefile?

That's not relevant.
The point is that imx93-9x9-qsb-tianma-tm050rdh03.dtbo would be generated
and applied by the user to imx93-9x9-qsb.dtb to enable the tianma,tm050rdh03
DPI panel.

> 
>>
>>>
>>> can the same board be use for imx91 or other evk boards?
>>
>> Yes, both tianma,tm050rdh03 and ontat,kd50g21-40nt-a1 DPI panels can be
>> connected to i.MX91/93 11x11 EVK and 9x9 QSB boards.
> 
> Is it possible to use one overlay files for all imx91/imx93 boards?

No, that's impossible, because they use GPIO backlight or PWM backlight,
different GPIOs to enable DPI panels and different GPIO hogs.

> 
> Frank
>>
>>>
>>> Frank
>>>
>>>>> Frank
>>>>>>
>>>>>> [2] https://www.nxp.com/design/design-center/development-boards-and-designs/mx93aud-hat-audio-board:MX93AUD-HAT
>>>>>>
>>>>>>>
>>>>>>> Frank
>>>>>>>>
>>>>>>>> ---
>>>>>>>> base-commit: 816f193dd0d95246f208590924dd962b192def78
>>>>>>>> change-id: 20260407-tianma-tm050rdh03-imx93-9x9-qsb-6e4bbbde3d08
>>>>>>>>
>>>>>>>> Best regards,
>>>>>>>> --
>>>>>>>> Liu Ying <victor.liu@nxp.com>
>>>>>>>>
>>>>>>
>>>>>> --
>>>>>> Regards,
>>>>>> Liu Ying
>>>>
>>>> --
>>>> Regards,
>>>> Liu Ying
>>
>> --
>> Regards,
>> Liu Ying

-- 
Regards,
Liu Ying