[PATCH RESEND v4 1/3] dt-bindings: lcdif: Document a imx6sx-lcdif fallback

[PATCH RESEND v4 1/3] dt-bindings: lcdif: Document a imx6sx-lcdif fallback

[Fabio Estevam]

imx6sx.dtsi has the following lcdif entries:

compatible = "fsl,imx6sx-lcdif", "fsl,imx28-lcdif";

This causes the following dt-schema warning:

['fsl,imx6sx-lcdif', 'fsl,imx28-lcdif'] is too long

To keep DT compatibility, document 'fsl,imx28-lcdif' as a possible
'fsl,imx6sx-lcdif' fallback.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 Documentation/devicetree/bindings/display/fsl,lcdif.yaml | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
index 2dd0411ec651..ce31b873fb95 100644
--- a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
+++ b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
@@ -19,7 +19,6 @@ properties:
       - enum:
           - fsl,imx23-lcdif
           - fsl,imx28-lcdif
-          - fsl,imx6sx-lcdif
           - fsl,imx8mp-lcdif
           - fsl,imx93-lcdif
       - items:
@@ -32,6 +31,10 @@ properties:
               - fsl,imx8mn-lcdif
               - fsl,imx8mq-lcdif
           - const: fsl,imx6sx-lcdif
+      - items:
+          - enum:
+              - fsl,imx6sx-lcdif
+          - const: fsl,imx28-lcdif
 
   reg:
     maxItems: 1
@@ -199,7 +202,7 @@ examples:
     #include <dt-bindings/interrupt-controller/arm-gic.h>
 
     display-controller@2220000 {
-        compatible = "fsl,imx6sx-lcdif";
+        compatible = "fsl,imx6sx-lcdif", "fsl,imx28-lcdif";
         reg = <0x02220000 0x4000>;
         interrupts = <GIC_SPI 5 IRQ_TYPE_LEVEL_HIGH>;
         clocks = <&clks IMX6SX_CLK_LCDIF1_PIX>,
-- 
2.34.1

[PATCH RESEND v4 1/3] dt-bindings: lcdif: Document a imx6sx-lcdif fallback

[Fabio Estevam]

imx6sx.dtsi has the following lcdif entries:

compatible = "fsl,imx6sx-lcdif", "fsl,imx28-lcdif";

This causes the following dt-schema warning:

['fsl,imx6sx-lcdif', 'fsl,imx28-lcdif'] is too long

To keep DT compatibility, document 'fsl,imx28-lcdif' as a possible
'fsl,imx6sx-lcdif' fallback.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
Hi Liu Ying,

Could you please help apply patches 1 and 2 to drm-misc?

I got several Reviewed-by/Acked-by tags on this series, but the patches were
not applied during several kernel cycles.

Thanks

 Documentation/devicetree/bindings/display/fsl,lcdif.yaml | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
index 2dd0411ec651..ce31b873fb95 100644
--- a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
+++ b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
@@ -19,7 +19,6 @@ properties:
       - enum:
           - fsl,imx23-lcdif
           - fsl,imx28-lcdif
-          - fsl,imx6sx-lcdif
           - fsl,imx8mp-lcdif
           - fsl,imx93-lcdif
       - items:
@@ -32,6 +31,10 @@ properties:
               - fsl,imx8mn-lcdif
               - fsl,imx8mq-lcdif
           - const: fsl,imx6sx-lcdif
+      - items:
+          - enum:
+              - fsl,imx6sx-lcdif
+          - const: fsl,imx28-lcdif
 
   reg:
     maxItems: 1
@@ -199,7 +202,7 @@ examples:
     #include <dt-bindings/interrupt-controller/arm-gic.h>
 
     display-controller@2220000 {
-        compatible = "fsl,imx6sx-lcdif";
+        compatible = "fsl,imx6sx-lcdif", "fsl,imx28-lcdif";
         reg = <0x02220000 0x4000>;
         interrupts = <GIC_SPI 5 IRQ_TYPE_LEVEL_HIGH>;
         clocks = <&clks IMX6SX_CLK_LCDIF1_PIX>,
-- 
2.34.1

[PATCH RESEND v4 2/3] dt-bindings: lcdif: Expand the imx6sl/imx6sll fallbacks

[Fabio Estevam]

mx6sl.dtsi and imx6sll.dtsi have the following lcdif entries:

compatible = "fsl,imx6sl-lcdif", "fsl,imx28-lcdif";

This causes dt-schema warnings as the current binding only
allow 'fsl,imx6sx-lcdif' as fallback.

['fsl,imx6sl-lcdif', 'fsl,imx28-lcdif'] is too long
['fsl,imx6sll-lcdif', 'fsl,imx28-lcdif'] is too long

The imx6sx-lcdif programming model has more advanced features, such
as overlay plane and the CRC32 support than the imx28-lcdif IP.

Expand the imx6sl/imx6sll lcdif fallbacks to accept a less specific
fsl,imx28-lcdif fallback:

compatible = "fsl,imx6sl-lcdif", "fsl,imx6sx-lcdif", "fsl,imx28-lcdif";

This helps keeping DT compatibility as well as using the more advanced
lcdif features found on imx6sl and imx6sll.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 Documentation/devicetree/bindings/display/fsl,lcdif.yaml | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
index ce31b873fb95..d665f3241e97 100644
--- a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
+++ b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
@@ -23,14 +23,18 @@ properties:
           - fsl,imx93-lcdif
       - items:
           - enum:
-              - fsl,imx6sl-lcdif
-              - fsl,imx6sll-lcdif
               - fsl,imx6ul-lcdif
               - fsl,imx7d-lcdif
               - fsl,imx8mm-lcdif
               - fsl,imx8mn-lcdif
               - fsl,imx8mq-lcdif
           - const: fsl,imx6sx-lcdif
+      - items:
+          - enum:
+              - fsl,imx6sl-lcdif
+              - fsl,imx6sll-lcdif
+          - const: fsl,imx6sx-lcdif
+          - const: fsl,imx28-lcdif
       - items:
           - enum:
               - fsl,imx6sx-lcdif
-- 
2.34.1

[PATCH RESEND v4 3/3] ARM: dts: imx6sl: Provide a more specific lcdif compatible

[Fabio Estevam]

The LCDIF IP on i.MX6SL and i.MX6SLL is compatible with i.MX6SX.

Provide a more specific "fsl,imx6sx-lcdif" compatible and still keep
"fsl,imx28-lcdif" for DT compatibility.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Reviewed-by: Frank Li <Frank.Li@nxp.com
---
 arch/arm/boot/dts/nxp/imx/imx6sl.dtsi  | 3 ++-
 arch/arm/boot/dts/nxp/imx/imx6sll.dtsi | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/nxp/imx/imx6sl.dtsi b/arch/arm/boot/dts/nxp/imx/imx6sl.dtsi
index 7381fb7f8912..074c48b04519 100644
--- a/arch/arm/boot/dts/nxp/imx/imx6sl.dtsi
+++ b/arch/arm/boot/dts/nxp/imx/imx6sl.dtsi
@@ -776,7 +776,8 @@ epdc: epdc@20f4000 {
 			};
 
 			lcdif: lcdif@20f8000 {
-				compatible = "fsl,imx6sl-lcdif", "fsl,imx28-lcdif";
+				compatible = "fsl,imx6sl-lcdif", "fsl,imx6sx-lcdif",
+					     "fsl,imx28-lcdif";
 				reg = <0x020f8000 0x4000>;
 				interrupts = <0 39 IRQ_TYPE_LEVEL_HIGH>;
 				clocks = <&clks IMX6SL_CLK_LCDIF_PIX>,
diff --git a/arch/arm/boot/dts/nxp/imx/imx6sll.dtsi b/arch/arm/boot/dts/nxp/imx/imx6sll.dtsi
index 8c5ca4f9b87f..745f3640e114 100644
--- a/arch/arm/boot/dts/nxp/imx/imx6sll.dtsi
+++ b/arch/arm/boot/dts/nxp/imx/imx6sll.dtsi
@@ -657,7 +657,8 @@ pxp: pxp@20f0000 {
 			};
 
 			lcdif: lcd-controller@20f8000 {
-				compatible = "fsl,imx6sll-lcdif", "fsl,imx28-lcdif";
+				compatible = "fsl,imx6sll-lcdif", "fsl,imx6sx-lcdif",
+					     "fsl,imx28-lcdif";
 				reg = <0x020f8000 0x4000>;
 				interrupts = <GIC_SPI 39 IRQ_TYPE_LEVEL_HIGH>;
 				clocks = <&clks IMX6SLL_CLK_LCDIF_PIX>,
-- 
2.34.1

Re: [PATCH RESEND v4 2/3] dt-bindings: lcdif: Expand the imx6sl/imx6sll fallbacks

[Liu Ying]

On 10/13/2025, Fabio Estevam wrote:
> mx6sl.dtsi and imx6sll.dtsi have the following lcdif entries:
> 
> compatible = "fsl,imx6sl-lcdif", "fsl,imx28-lcdif";
> 
> This causes dt-schema warnings as the current binding only
> allow 'fsl,imx6sx-lcdif' as fallback.
> 
> ['fsl,imx6sl-lcdif', 'fsl,imx28-lcdif'] is too long
> ['fsl,imx6sll-lcdif', 'fsl,imx28-lcdif'] is too long
> 
> The imx6sx-lcdif programming model has more advanced features, such
> as overlay plane and the CRC32 support than the imx28-lcdif IP.

Sorry for the late comment, but the LCDIF chapter in i.MX28 TRM contains
the CRC register too, though I agree that i.MX6SX LCDIF supports overlay
plane while i.MX28 LCDIF doesn't.

> 
> Expand the imx6sl/imx6sll lcdif fallbacks to accept a less specific
> fsl,imx28-lcdif fallback:
> 
> compatible = "fsl,imx6sl-lcdif", "fsl,imx6sx-lcdif", "fsl,imx28-lcdif";

Looking at i.MX6SL TRM, I don't find any register to control overlay plane
in LCDIF chapter, so I don't think i.MX6SL LCDIF supports overlay plane
like i.MX6SX LCDIF does.  So, why not make the DT binding allow
"compatible = "fsl,imx6sl-lcdif", "fsl,imx28-lcdif";" instead?

I'm assuming i.MX6SL LCDIF and i.MX6SLL LCDIF are exactly the same.

> 
> This helps keeping DT compatibility as well as using the more advanced
> lcdif features found on imx6sl and imx6sll.
> 
> Signed-off-by: Fabio Estevam <festevam@gmail.com>
> Acked-by: Rob Herring (Arm) <robh@kernel.org>
> Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> Reviewed-by: Frank Li <Frank.Li@nxp.com>
> ---
>  Documentation/devicetree/bindings/display/fsl,lcdif.yaml | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
> index ce31b873fb95..d665f3241e97 100644
> --- a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
> +++ b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
> @@ -23,14 +23,18 @@ properties:
>            - fsl,imx93-lcdif
>        - items:
>            - enum:
> -              - fsl,imx6sl-lcdif
> -              - fsl,imx6sll-lcdif
>                - fsl,imx6ul-lcdif
>                - fsl,imx7d-lcdif
>                - fsl,imx8mm-lcdif
>                - fsl,imx8mn-lcdif
>                - fsl,imx8mq-lcdif
>            - const: fsl,imx6sx-lcdif
> +      - items:
> +          - enum:
> +              - fsl,imx6sl-lcdif
> +              - fsl,imx6sll-lcdif
> +          - const: fsl,imx6sx-lcdif
> +          - const: fsl,imx28-lcdif
>        - items:
>            - enum:
>                - fsl,imx6sx-lcdif


-- 
Regards,
Liu Ying

Re: [PATCH RESEND v4 1/3] dt-bindings: lcdif: Document a imx6sx-lcdif fallback

[Liu Ying]

On 10/13/2025, Fabio Estevam wrote:
> imx6sx.dtsi has the following lcdif entries:
> 
> compatible = "fsl,imx6sx-lcdif", "fsl,imx28-lcdif";
> 
> This causes the following dt-schema warning:
> 
> ['fsl,imx6sx-lcdif', 'fsl,imx28-lcdif'] is too long
> 
> To keep DT compatibility, document 'fsl,imx28-lcdif' as a possible
> 'fsl,imx6sx-lcdif' fallback.
> 
> Signed-off-by: Fabio Estevam <festevam@gmail.com>
> Acked-by: Rob Herring (Arm) <robh@kernel.org>
> Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> ---
> Hi Liu Ying,

Hi,

> 
> Could you please help apply patches 1 and 2 to drm-misc?

As Marek and Stefan are the two maintainers of "MXSFB DRM DRIVER" according
to MAINTAINERS, they are the first two supposed to conduct apply if needed.
But I can help apply if they don't respond and all my comments are addressed.

> 
> I got several Reviewed-by/Acked-by tags on this series, but the patches were
> not applied during several kernel cycles.
> 
> Thanks
> 
>  Documentation/devicetree/bindings/display/fsl,lcdif.yaml | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
> index 2dd0411ec651..ce31b873fb95 100644
> --- a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
> +++ b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
> @@ -19,7 +19,6 @@ properties:
>        - enum:
>            - fsl,imx23-lcdif
>            - fsl,imx28-lcdif
> -          - fsl,imx6sx-lcdif
>            - fsl,imx8mp-lcdif
>            - fsl,imx93-lcdif
>        - items:
> @@ -32,6 +31,10 @@ properties:
>                - fsl,imx8mn-lcdif
>                - fsl,imx8mq-lcdif
>            - const: fsl,imx6sx-lcdif
> +      - items:
> +          - enum:
> +              - fsl,imx6sx-lcdif
> +          - const: fsl,imx28-lcdif

Strictly speaking, I don't think i.MX6SX LCDIF is compatible with i.MX28 LCDIF
because at least i.MX28 LCDIF has the version and debug{0,1,2} registers(at
0x1c0, 0x1d0, 0x1e0 and 0x1f0) while i.MX6SX LCDIF hasn't.

>  
>    reg:
>      maxItems: 1
> @@ -199,7 +202,7 @@ examples:
>      #include <dt-bindings/interrupt-controller/arm-gic.h>
>  
>      display-controller@2220000 {
> -        compatible = "fsl,imx6sx-lcdif";
> +        compatible = "fsl,imx6sx-lcdif", "fsl,imx28-lcdif";
>          reg = <0x02220000 0x4000>;
>          interrupts = <GIC_SPI 5 IRQ_TYPE_LEVEL_HIGH>;
>          clocks = <&clks IMX6SX_CLK_LCDIF1_PIX>,


-- 
Regards,
Liu Ying

Re: [PATCH RESEND v4 1/3] dt-bindings: lcdif: Document a imx6sx-lcdif fallback

[Fabio Estevam]

Hi Liu,

On Tue, Oct 14, 2025 at 1:12 AM Liu Ying <victor.liu@nxp.com> wrote:

> Strictly speaking, I don't think i.MX6SX LCDIF is compatible with i.MX28 LCDIF
> because at least i.MX28 LCDIF has the version and debug{0,1,2} registers(at
> 0x1c0, 0x1d0, 0x1e0 and 0x1f0) while i.MX6SX LCDIF hasn't.

There are some DT users, such as Barebox that matches against
fsl,imx28-lcdif, so we cannot remove it.

In my first attempt,  I tried removing it:

https://lore.kernel.org/linux-devicetree/20241028180844.154349-2-festevam@gmail.com/

but this was rejected due to potential dtb compatibility breakage:

https://lore.kernel.org/linux-devicetree/4addc413-dd13-4867-8c49-45539af7b45b@pengutronix.de/

Re: [PATCH RESEND v4 1/3] dt-bindings: lcdif: Document a imx6sx-lcdif fallback

[Liu Ying]

On 10/20/2025, Fabio Estevam wrote:
> Hi Liu,

Hi Fabio,

> 
> On Tue, Oct 14, 2025 at 1:12 AM Liu Ying <victor.liu@nxp.com> wrote:
> 
>> Strictly speaking, I don't think i.MX6SX LCDIF is compatible with i.MX28 LCDIF
>> because at least i.MX28 LCDIF has the version and debug{0,1,2} registers(at
>> 0x1c0, 0x1d0, 0x1e0 and 0x1f0) while i.MX6SX LCDIF hasn't.
> 
> There are some DT users, such as Barebox that matches against
> fsl,imx28-lcdif, so we cannot remove it.

Hmmm, it looks like software projects like Barebox don't really follow this DT
binding.  Is it possible to fix Barebox to avoid changing this DT binding by
this patch?  I'm assuming that Uboot has already been fixed.

> 
> In my first attempt,  I tried removing it:
> 
> https://lore.kernel.org/linux-devicetree/20241028180844.154349-2-festevam@gmail.com/
> 
> but this was rejected due to potential dtb compatibility breakage:
> 
> https://lore.kernel.org/linux-devicetree/4addc413-dd13-4867-8c49-45539af7b45b@pengutronix.de/


-- 
Regards,
Liu Ying

Re: [PATCH RESEND v4 1/3] dt-bindings: lcdif: Document a imx6sx-lcdif fallback

[Fabio Estevam]

Hi Ahmad,

On Mon, Oct 20, 2025 at 11:53 PM Liu Ying <victor.liu@nxp.com> wrote:
>
> On 10/20/2025, Fabio Estevam wrote:
> > Hi Liu,
>
> Hi Fabio,
>
> >
> > On Tue, Oct 14, 2025 at 1:12 AM Liu Ying <victor.liu@nxp.com> wrote:
> >
> >> Strictly speaking, I don't think i.MX6SX LCDIF is compatible with i.MX28 LCDIF
> >> because at least i.MX28 LCDIF has the version and debug{0,1,2} registers(at
> >> 0x1c0, 0x1d0, 0x1e0 and 0x1f0) while i.MX6SX LCDIF hasn't.
> >
> > There are some DT users, such as Barebox that matches against
> > fsl,imx28-lcdif, so we cannot remove it.
>
> Hmmm, it looks like software projects like Barebox don't really follow this DT
> binding.  Is it possible to fix Barebox to avoid changing this DT binding by
> this patch?  I'm assuming that Uboot has already been fixed.

What do you think?

Thanks

Re: [PATCH RESEND v4 1/3] dt-bindings: lcdif: Document a imx6sx-lcdif fallback

[Ahmad Fatoum]

Hi,

On 04.11.25 21:44, Fabio Estevam wrote:
> On Mon, Oct 20, 2025 at 11:53 PM Liu Ying <victor.liu@nxp.com> wrote:
>> On 10/20/2025, Fabio Estevam wrote:
>>> On Tue, Oct 14, 2025 at 1:12 AM Liu Ying <victor.liu@nxp.com> wrote:
>>>
>>>> Strictly speaking, I don't think i.MX6SX LCDIF is compatible with i.MX28 LCDIF
>>>> because at least i.MX28 LCDIF has the version and debug{0,1,2} registers(at
>>>> 0x1c0, 0x1d0, 0x1e0 and 0x1f0) while i.MX6SX LCDIF hasn't.

Thanks for pointing this out. In my opinion, these registers are auxiliary
and don't really change the compatibility situation as a functional driver
can be written without their use, evidenced by the Linux driver doing just
fine without using these registers.

>>> There are some DT users, such as Barebox that matches against
>>> fsl,imx28-lcdif, so we cannot remove it.
>>
>> Hmmm, it looks like software projects like Barebox don't really follow this DT
>> binding.  Is it possible to fix Barebox to avoid changing this DT binding by
>> this patch?  I'm assuming that Uboot has already been fixed.
> > What do you think?

I am sorry my prior feedback ended up stalling this series.

There is a lot of regressions happening due to upstream DT changes and I am
just trying to raise awareness. Another example I stumbled over today:
https://lore.kernel.org/all/91f764ab-bec1-4791-b01b-3ba0803ce8f8@pengutronix.de/


I have submitted a patch[1] to barebox adding explicit i.MX6 SoloX support,
so, having expressed my opinion above, please proceed as you see fit.

[1]: https://lore.barebox.org/barebox/20251107210033.2229781-3-a.fatoum@barebox.org/

Cheers,
Ahmad

> 
> Thanks
> 


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Re: [PATCH RESEND v4 1/3] dt-bindings: lcdif: Document a imx6sx-lcdif fallback

[Liu Ying]

On 11/07/2025, Ahmad Fatoum wrote:
> Hi,

Hi,

> 
> On 04.11.25 21:44, Fabio Estevam wrote:
>> On Mon, Oct 20, 2025 at 11:53 PM Liu Ying <victor.liu@nxp.com> wrote:
>>> On 10/20/2025, Fabio Estevam wrote:
>>>> On Tue, Oct 14, 2025 at 1:12 AM Liu Ying <victor.liu@nxp.com> wrote:
>>>>
>>>>> Strictly speaking, I don't think i.MX6SX LCDIF is compatible with i.MX28 LCDIF
>>>>> because at least i.MX28 LCDIF has the version and debug{0,1,2} registers(at
>>>>> 0x1c0, 0x1d0, 0x1e0 and 0x1f0) while i.MX6SX LCDIF hasn't.
> 
> Thanks for pointing this out. In my opinion, these registers are auxiliary
> and don't really change the compatibility situation as a functional driver
> can be written without their use, evidenced by the Linux driver doing just
> fine without using these registers.

DT bindings should after all describe hardwares and in theory they should not
consider software implementation, that's why I said 'strictly speaking'.

People may argue that potential software would access those "auxiliary"
registers and hence i.MX28 LCDIF is not a fallback for i.MX6SX LCDIF.

And, to me, register at 0x1e0, i.e., HW_LCDIF_DEBUG1 is not that "auxiliary"
at least for Linux, because Linux DRM supports getting current display scanout
position to generate accurate vblank timestamp.  HW_LCDIF_DEBUG1 actually
provides the interface to read scanout position.

https://elixir.bootlin.com/linux/v6.18-rc1/source/include/drm/drm_modeset_helper_vtables.h#L448

> 
>>>> There are some DT users, such as Barebox that matches against
>>>> fsl,imx28-lcdif, so we cannot remove it.
>>>
>>> Hmmm, it looks like software projects like Barebox don't really follow this DT
>>> binding.  Is it possible to fix Barebox to avoid changing this DT binding by
>>> this patch?  I'm assuming that Uboot has already been fixed.
>>> What do you think?
> 
> I am sorry my prior feedback ended up stalling this series.
> 
> There is a lot of regressions happening due to upstream DT changes and I am
> just trying to raise awareness. Another example I stumbled over today:
> https://lore.kernel.org/all/91f764ab-bec1-4791-b01b-3ba0803ce8f8@pengutronix.de/
> 
> 
> I have submitted a patch[1] to barebox adding explicit i.MX6 SoloX support,
> so, having expressed my opinion above, please proceed as you see fit.

Fabio, it seems after Barebox is fixed, you can fix the LCDIF compatible
strings in imx6sx.dtsi?  I don't know if there is any other software project
which is taking fsl,imx28-lcdif as a fallback for i.MX6SX LCDIF...

> 
> [1]: https://lore.barebox.org/barebox/20251107210033.2229781-3-a.fatoum@barebox.org/
> 
> Cheers,
> Ahmad
> 
>>
>> Thanks
>>
> 
> 


-- 
Regards,
Liu Ying