[PATCH 0/5] drm/panel: atna33xc20: Fix the Samsung ATNA45AF01 panel

[PATCH 0/5] drm/panel: atna33xc20: Fix the Samsung ATNA45AF01 panel

[Stephan Gerhold]

The backlight of the Samsung ATNA45AF01 panel used in the Qualcomm X1E80100
CRD does not work correctly with the current display panel configuration
and drivers: It works after boot, but once the display gets disabled it is
not possible to get it back on. It turns out that the ATNA45AF01 panel
needs exactly the same non-standard power sequence as implemented for
ATNA33XC20 in the panel-samsung-atna33xc20 driver.

Move the ATNA45AF01 panel from the generic panel-edp driver to the
panel-samsung-atna33xc20 driver and fix the panel configuration in the
x1e80100-crd device tree to make the panel work correctly.

The DT changes are included here for reference and easier testing, I assume
Bjorn or Konrad will pick them up after the DRM panel changes were applied.

Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
---
Stephan Gerhold (5):
      dt-bindings: display: panel: samsung,atna33xc20: Document ATNA45AF01
      drm/panel: samsung-atna33xc20: Add compatible for ATNA45AF01
      Revert "drm/panel-edp: Add SDC ATNA45AF01"
      arm64: dts: qcom: x1e80100-crd: Fix backlight
      arm64: defconfig: Add CONFIG_DRM_PANEL_SAMSUNG_ATNA33XC20

 .../bindings/display/panel/samsung,atna33xc20.yaml      |  6 +++++-
 arch/arm64/boot/dts/qcom/x1e80100-crd.dts               | 17 +++++++++++++++--
 arch/arm64/configs/defconfig                            |  1 +
 drivers/gpu/drm/panel/panel-edp.c                       |  2 --
 drivers/gpu/drm/panel/panel-samsung-atna33xc20.c        |  1 +
 5 files changed, 22 insertions(+), 5 deletions(-)
---
base-commit: 523b23f0bee3014a7a752c9bb9f5c54f0eddae88
change-id: 20240710-x1e80100-crd-backlight-632f9bf936ef

Best regards,
-- 
Stephan Gerhold <stephan.gerhold@linaro.org>

[PATCH 1/5] dt-bindings: display: panel: samsung,atna33xc20: Document ATNA45AF01

[Stephan Gerhold]

The Samsung ATNA45AF01 panel is an AMOLED eDP panel that has backlight
control over the DP AUX channel. While it works almost correctly with the
generic "edp-panel" compatible, the backlight needs special handling to
work correctly. It is similar to the existing ATNA33XC20 panel, just with
a larger resolution and size.

Add a new "samsung,atna45af01" compatible to describe this panel in the DT.

Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
---
 .../devicetree/bindings/display/panel/samsung,atna33xc20.yaml       | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml b/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml
index 765ca155c83a..d668e8d0d296 100644
--- a/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml
+++ b/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml
@@ -14,7 +14,11 @@ allOf:
 
 properties:
   compatible:
-    const: samsung,atna33xc20
+    enum:
+      # Samsung 13.3" FHD (1920x1080 pixels) eDP AMOLED panel
+      - samsung,atna33xc20
+      # Samsung 14.5" WQXGA+ (2880x1800 pixels) eDP AMOLED panel
+      - samsung,atna45af01
 
   enable-gpios: true
   port: true

-- 
2.44.1

Re: [PATCH 1/5] dt-bindings: display: panel: samsung,atna33xc20: Document ATNA45AF01

[Doug Anderson]

Hi,

On Wed, Jul 10, 2024 at 10:05 AM Stephan Gerhold
<stephan.gerhold@linaro.org> wrote:
>
> The Samsung ATNA45AF01 panel is an AMOLED eDP panel that has backlight
> control over the DP AUX channel. While it works almost correctly with the
> generic "edp-panel" compatible, the backlight needs special handling to
> work correctly. It is similar to the existing ATNA33XC20 panel, just with
> a larger resolution and size.
>
> Add a new "samsung,atna45af01" compatible to describe this panel in the DT.
>
> Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
> ---
>  .../devicetree/bindings/display/panel/samsung,atna33xc20.yaml       | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml b/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml
> index 765ca155c83a..d668e8d0d296 100644
> --- a/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml
> +++ b/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml
> @@ -14,7 +14,11 @@ allOf:
>
>  properties:
>    compatible:
> -    const: samsung,atna33xc20
> +    enum:
> +      # Samsung 13.3" FHD (1920x1080 pixels) eDP AMOLED panel
> +      - samsung,atna33xc20
> +      # Samsung 14.5" WQXGA+ (2880x1800 pixels) eDP AMOLED panel
> +      - samsung,atna45af01

Seems OK, but a few thoughts:

1. Is it worth renaming this file? Something like
"samsung,atna-oled-panel.yaml"? I'd be interested in DT maintainer
folks' opinions here.

2. In theory you could make your compatible look like this:

compatible = "samsung,atna45af01", "samsung,atna33xc20"

...which would say "I have a 45af01 but if the OS doesn't have
anything special to do that it would be fine to use the 33xc20
driver". That would allow device trees to work without the kernel
changes and would allow you to land the DT changes in parallel with
the driver changes and things would keep working.

...and, in fact, that would mean you _didn't_ need to add the new
compatible string to the driver, which is nice.


-Doug

Re: [PATCH 1/5] dt-bindings: display: panel: samsung,atna33xc20: Document ATNA45AF01

[Stephan Gerhold]

On Wed, Jul 10, 2024 at 10:35:28AM -0700, Doug Anderson wrote:
> On Wed, Jul 10, 2024 at 10:05 AM Stephan Gerhold
> <stephan.gerhold@linaro.org> wrote:
> >
> > The Samsung ATNA45AF01 panel is an AMOLED eDP panel that has backlight
> > control over the DP AUX channel. While it works almost correctly with the
> > generic "edp-panel" compatible, the backlight needs special handling to
> > work correctly. It is similar to the existing ATNA33XC20 panel, just with
> > a larger resolution and size.
> >
> > Add a new "samsung,atna45af01" compatible to describe this panel in the DT.
> >
> > Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
> > ---
> >  .../devicetree/bindings/display/panel/samsung,atna33xc20.yaml       | 6 +++++-
> >  1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml b/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml
> > index 765ca155c83a..d668e8d0d296 100644
> > --- a/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml
> > +++ b/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml
> > @@ -14,7 +14,11 @@ allOf:
> >
> >  properties:
> >    compatible:
> > -    const: samsung,atna33xc20
> > +    enum:
> > +      # Samsung 13.3" FHD (1920x1080 pixels) eDP AMOLED panel
> > +      - samsung,atna33xc20
> > +      # Samsung 14.5" WQXGA+ (2880x1800 pixels) eDP AMOLED panel
> > +      - samsung,atna45af01
> 
> Seems OK, but a few thoughts:
> 
> 1. Is it worth renaming this file? Something like
> "samsung,atna-oled-panel.yaml"? I'd be interested in DT maintainer
> folks' opinions here.
> 

I think examples for both approaches exist in the kernel tree, so I am
also interested in the opinion of the DT maintainers here. :-)

> 2. In theory you could make your compatible look like this:
> 
> compatible = "samsung,atna45af01", "samsung,atna33xc20"
> 
> ...which would say "I have a 45af01 but if the OS doesn't have
> anything special to do that it would be fine to use the 33xc20
> driver". That would allow device trees to work without the kernel
> changes and would allow you to land the DT changes in parallel with
> the driver changes and things would keep working.
> 
> ...and, in fact, that would mean you _didn't_ need to add the new
> compatible string to the driver, which is nice.
> 

Yeah, I considered this. I mentioned the reason why I decided against
this in patch 2:

> While ATNA45AF01 would also work with "samsung,atna33xc20" as a fallback
> compatible, the original submission of the compatible in commit
> 4bfe6c8f7c23 ("drm/panel-simple: Add Samsung ATNA33XC20") had the timings
> and resolution hardcoded. These would not work for ATNA45AF01.

Basically, it works with the current driver. But if you would run the
kernel at the state of the original submission then it would behave
incorrectly. This is why I considered the resolution and timings to be
part of the "samsung,atna33xc20" "ABI". The new panel would not be
compatible with that.

I don't mind changing it, if there is consensus that we should ignore
this and use the fallback compatible instead.

Thanks,
Stephan

Re: [PATCH 1/5] dt-bindings: display: panel: samsung,atna33xc20: Document ATNA45AF01

[Doug Anderson]

Hi,

On Wed, Jul 10, 2024 at 12:03 PM Stephan Gerhold
<stephan.gerhold@linaro.org> wrote:
>
> > 2. In theory you could make your compatible look like this:
> >
> > compatible = "samsung,atna45af01", "samsung,atna33xc20"
> >
> > ...which would say "I have a 45af01 but if the OS doesn't have
> > anything special to do that it would be fine to use the 33xc20
> > driver". That would allow device trees to work without the kernel
> > changes and would allow you to land the DT changes in parallel with
> > the driver changes and things would keep working.
> >
> > ...and, in fact, that would mean you _didn't_ need to add the new
> > compatible string to the driver, which is nice.
> >
>
> Yeah, I considered this. I mentioned the reason why I decided against
> this in patch 2:
>
> > While ATNA45AF01 would also work with "samsung,atna33xc20" as a fallback
> > compatible, the original submission of the compatible in commit
> > 4bfe6c8f7c23 ("drm/panel-simple: Add Samsung ATNA33XC20") had the timings
> > and resolution hardcoded. These would not work for ATNA45AF01.
>
> Basically, it works with the current driver. But if you would run the
> kernel at the state of the original submission then it would behave
> incorrectly. This is why I considered the resolution and timings to be
> part of the "samsung,atna33xc20" "ABI". The new panel would not be
> compatible with that.

Ah, oops. My eyes totally glazed over the description since the patch
was so simple. :-P Sorry about that.

IMO I'd still prefer using the fallback compatible, but happy to hear
other opinions. In the original commit things were pretty broken still
(sorta like how it's broken for you using "edp-panel") and the
resolution hasn't been hardcoded for a long while...

Re: [PATCH 1/5] dt-bindings: display: panel: samsung,atna33xc20: Document ATNA45AF01

[Stephan Gerhold]

On Wed, Jul 10, 2024 at 12:16:58PM -0700, Doug Anderson wrote:
> On Wed, Jul 10, 2024 at 12:03 PM Stephan Gerhold
> <stephan.gerhold@linaro.org> wrote:
> >
> > > 2. In theory you could make your compatible look like this:
> > >
> > > compatible = "samsung,atna45af01", "samsung,atna33xc20"
> > >
> > > ...which would say "I have a 45af01 but if the OS doesn't have
> > > anything special to do that it would be fine to use the 33xc20
> > > driver". That would allow device trees to work without the kernel
> > > changes and would allow you to land the DT changes in parallel with
> > > the driver changes and things would keep working.
> > >
> > > ...and, in fact, that would mean you _didn't_ need to add the new
> > > compatible string to the driver, which is nice.
> > >
> >
> > Yeah, I considered this. I mentioned the reason why I decided against
> > this in patch 2:
> >
> > > While ATNA45AF01 would also work with "samsung,atna33xc20" as a fallback
> > > compatible, the original submission of the compatible in commit
> > > 4bfe6c8f7c23 ("drm/panel-simple: Add Samsung ATNA33XC20") had the timings
> > > and resolution hardcoded. These would not work for ATNA45AF01.
> >
> > Basically, it works with the current driver. But if you would run the
> > kernel at the state of the original submission then it would behave
> > incorrectly. This is why I considered the resolution and timings to be
> > part of the "samsung,atna33xc20" "ABI". The new panel would not be
> > compatible with that.
> 
> Ah, oops. My eyes totally glazed over the description since the patch
> was so simple. :-P Sorry about that.
> 
> IMO I'd still prefer using the fallback compatible, but happy to hear
> other opinions. In the original commit things were pretty broken still
> (sorta like how it's broken for you using "edp-panel") and the
> resolution hasn't been hardcoded for a long while...

I briefly discussed this with Krzysztof on IRC yesterday and we
concluded that a fallback compatible is better. If one considers just
the non-discoverable part of the interface for the binding (i.e. the
non-standard power sequence), then the two panels are indeed compatible.

I will send a v2 with the fallback compatible on Monday. I think this
can also simplify backporting the backlight fix as you mentioned, since
then no driver change is required to make it work.

Thanks,
Stephan

Re: [PATCH 1/5] dt-bindings: display: panel: samsung,atna33xc20: Document ATNA45AF01

[Krzysztof Kozlowski]

On 10/07/2024 19:35, Doug Anderson wrote:
> Hi,
> 
> On Wed, Jul 10, 2024 at 10:05 AM Stephan Gerhold
> <stephan.gerhold@linaro.org> wrote:
>>
>> The Samsung ATNA45AF01 panel is an AMOLED eDP panel that has backlight
>> control over the DP AUX channel. While it works almost correctly with the
>> generic "edp-panel" compatible, the backlight needs special handling to
>> work correctly. It is similar to the existing ATNA33XC20 panel, just with
>> a larger resolution and size.
>>
>> Add a new "samsung,atna45af01" compatible to describe this panel in the DT.
>>
>> Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
>> ---
>>  .../devicetree/bindings/display/panel/samsung,atna33xc20.yaml       | 6 +++++-
>>  1 file changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml b/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml
>> index 765ca155c83a..d668e8d0d296 100644
>> --- a/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml
>> +++ b/Documentation/devicetree/bindings/display/panel/samsung,atna33xc20.yaml
>> @@ -14,7 +14,11 @@ allOf:
>>
>>  properties:
>>    compatible:
>> -    const: samsung,atna33xc20
>> +    enum:
>> +      # Samsung 13.3" FHD (1920x1080 pixels) eDP AMOLED panel
>> +      - samsung,atna33xc20
>> +      # Samsung 14.5" WQXGA+ (2880x1800 pixels) eDP AMOLED panel
>> +      - samsung,atna45af01
> 
> Seems OK, but a few thoughts:
> 
> 1. Is it worth renaming this file? Something like
> "samsung,atna-oled-panel.yaml"? I'd be interested in DT maintainer
> folks' opinions here.

No, rather keep existing name, because it should be based on compatible.

Best regards,
Krzysztof

Re: [PATCH 1/5] dt-bindings: display: panel: samsung,atna33xc20: Document ATNA45AF01

[Krzysztof Kozlowski]

On 10/07/2024 19:04, Stephan Gerhold wrote:
> The Samsung ATNA45AF01 panel is an AMOLED eDP panel that has backlight
> control over the DP AUX channel. While it works almost correctly with the
> generic "edp-panel" compatible, the backlight needs special handling to
> work correctly. It is similar to the existing ATNA33XC20 panel, just with
> a larger resolution and size.
> 
> Add a new "samsung,atna45af01" compatible to describe this panel in the DT.
> 
> Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
> ---

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

[PATCH 2/5] drm/panel: samsung-atna33xc20: Add compatible for ATNA45AF01

[Stephan Gerhold]

The Samsung ATNA45AF01 panel needs exactly the same non-standard power
sequence as the Samsung ATNA33XC20 panel for backlight to work properly.
Add the new "samsung,atna45af01" compatible to the driver to make it handle
these panels as well.

While ATNA45AF01 would also work with "samsung,atna33xc20" as a fallback
compatible, the original submission of the compatible in commit
4bfe6c8f7c23 ("drm/panel-simple: Add Samsung ATNA33XC20") had the timings
and resolution hardcoded. These would not work for ATNA45AF01.

Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
---
 drivers/gpu/drm/panel/panel-samsung-atna33xc20.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/panel/panel-samsung-atna33xc20.c b/drivers/gpu/drm/panel/panel-samsung-atna33xc20.c
index 9a482a744b8c..fd56fd02df87 100644
--- a/drivers/gpu/drm/panel/panel-samsung-atna33xc20.c
+++ b/drivers/gpu/drm/panel/panel-samsung-atna33xc20.c
@@ -333,6 +333,7 @@ static void atana33xc20_remove(struct dp_aux_ep_device *aux_ep)
 
 static const struct of_device_id atana33xc20_dt_match[] = {
 	{ .compatible = "samsung,atna33xc20", },
+	{ .compatible = "samsung,atna45af01", },
 	{ /* sentinal */ }
 };
 MODULE_DEVICE_TABLE(of, atana33xc20_dt_match);

-- 
2.44.1

Re: [PATCH 2/5] drm/panel: samsung-atna33xc20: Add compatible for ATNA45AF01

[Doug Anderson]

Hi,

On Wed, Jul 10, 2024 at 10:05 AM Stephan Gerhold
<stephan.gerhold@linaro.org> wrote:
>
> The Samsung ATNA45AF01 panel needs exactly the same non-standard power
> sequence as the Samsung ATNA33XC20 panel for backlight to work properly.
> Add the new "samsung,atna45af01" compatible to the driver to make it handle
> these panels as well.
>
> While ATNA45AF01 would also work with "samsung,atna33xc20" as a fallback
> compatible, the original submission of the compatible in commit
> 4bfe6c8f7c23 ("drm/panel-simple: Add Samsung ATNA33XC20") had the timings
> and resolution hardcoded. These would not work for ATNA45AF01.
>
> Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
> ---
>  drivers/gpu/drm/panel/panel-samsung-atna33xc20.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/gpu/drm/panel/panel-samsung-atna33xc20.c b/drivers/gpu/drm/panel/panel-samsung-atna33xc20.c
> index 9a482a744b8c..fd56fd02df87 100644
> --- a/drivers/gpu/drm/panel/panel-samsung-atna33xc20.c
> +++ b/drivers/gpu/drm/panel/panel-samsung-atna33xc20.c
> @@ -333,6 +333,7 @@ static void atana33xc20_remove(struct dp_aux_ep_device *aux_ep)
>
>  static const struct of_device_id atana33xc20_dt_match[] = {
>         { .compatible = "samsung,atna33xc20", },
> +       { .compatible = "samsung,atna45af01", },

As per my response to patch #1, you don't need this change at all if
you just add a fallback compatible. Later if there is anything special
we need to do for this panel we can match against it, but right now
there is no need.


-Doug

[PATCH 3/5] Revert "drm/panel-edp: Add SDC ATNA45AF01"

[Stephan Gerhold]

This reverts commit 8ebb1fc2e69ab8b89a425e402c7bd85e053b7b01.

The panel should be handled through the samsung-atna33xc20 driver for
correct power up timings. Otherwise the backlight does not work correctly.

We have existing users of this panel through the generic "edp-panel"
compatible (e.g. the Qualcomm X1E80100 CRD), but the screen works only
partially in that configuration: It works after boot but once the screen
gets disabled it does not turn on again until after reboot. It behaves the
same way with the default "conservative" timings, so we might as well drop
the configuration from the panel-edp driver. That way, users with old DTBs
will get a warning and can move to the new driver.

Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
---
 drivers/gpu/drm/panel/panel-edp.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-edp.c b/drivers/gpu/drm/panel/panel-edp.c
index 3a574a9b46e7..d2d682385e89 100644
--- a/drivers/gpu/drm/panel/panel-edp.c
+++ b/drivers/gpu/drm/panel/panel-edp.c
@@ -1960,8 +1960,6 @@ static const struct edp_panel_entry edp_panels[] = {
 	EDP_PANEL_ENTRY('L', 'G', 'D', 0x05af, &delay_200_500_e200_d200, "Unknown"),
 	EDP_PANEL_ENTRY('L', 'G', 'D', 0x05f1, &delay_200_500_e200_d200, "Unknown"),
 
-	EDP_PANEL_ENTRY('S', 'D', 'C', 0x416d, &delay_100_500_e200, "ATNA45AF01"),
-
 	EDP_PANEL_ENTRY('S', 'H', 'P', 0x1511, &delay_200_500_e50, "LQ140M1JW48"),
 	EDP_PANEL_ENTRY('S', 'H', 'P', 0x1523, &delay_80_500_e50, "LQ140M1JW46"),
 	EDP_PANEL_ENTRY('S', 'H', 'P', 0x153a, &delay_200_500_e50, "LQ140T1JH01"),

-- 
2.44.1

Re: [PATCH 3/5] Revert "drm/panel-edp: Add SDC ATNA45AF01"

[Doug Anderson]

Hi,

On Wed, Jul 10, 2024 at 10:05 AM Stephan Gerhold
<stephan.gerhold@linaro.org> wrote:
>
> This reverts commit 8ebb1fc2e69ab8b89a425e402c7bd85e053b7b01.
>
> The panel should be handled through the samsung-atna33xc20 driver for
> correct power up timings. Otherwise the backlight does not work correctly.
>
> We have existing users of this panel through the generic "edp-panel"
> compatible (e.g. the Qualcomm X1E80100 CRD), but the screen works only
> partially in that configuration: It works after boot but once the screen
> gets disabled it does not turn on again until after reboot. It behaves the
> same way with the default "conservative" timings, so we might as well drop
> the configuration from the panel-edp driver. That way, users with old DTBs
> will get a warning and can move to the new driver.
>
> Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
> ---
>  drivers/gpu/drm/panel/panel-edp.c | 2 --
>  1 file changed, 2 deletions(-)

Reviewed-by: Douglas Anderson <dianders@chromium.org>

[PATCH 4/5] arm64: dts: qcom: x1e80100-crd: Fix backlight

[Stephan Gerhold]

The backlight does not work correctly with the current display panel
configuration: It works after boot, but once the display gets disabled it
is not possible to get it back on. It turns out that the ATNA45AF01 panel
needs exactly the same non-standard power sequence as implemented by the
panel-samsung-atna33xc20 driver for sc7180-trogdor-homestar.

Switch the panel in the DT to the new compatible and make two more changes
to make it work correctly:

 1. Add the missing GPIO for the panel EL_ON3 line (EDP_BL_EN on CRD and
    enable-gpios in the DT).
 2. Drop the regulator-always-on for the panel regulator. The panel does
    not seem to power off properly if the regulator stays on.

Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
---
 arch/arm64/boot/dts/qcom/x1e80100-crd.dts | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
index 6152bcd0bc1f..7d6800dd9b8a 100644
--- a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
+++ b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
@@ -268,7 +268,6 @@ vreg_edp_3p3: regulator-edp-3p3 {
 		pinctrl-0 = <&edp_reg_en>;
 		pinctrl-names = "default";
 
-		regulator-always-on;
 		regulator-boot-on;
 	};
 
@@ -724,9 +723,13 @@ &mdss_dp3 {
 
 	aux-bus {
 		panel {
-			compatible = "edp-panel";
+			compatible = "samsung,atna45af01";
+			enable-gpios = <&pmc8380_3_gpios 4 GPIO_ACTIVE_HIGH>;
 			power-supply = <&vreg_edp_3p3>;
 
+			pinctrl-0 = <&edp_bl_en>;
+			pinctrl-names = "default";
+
 			port {
 				edp_panel_in: endpoint {
 					remote-endpoint = <&mdss_dp3_out>;
@@ -785,6 +788,16 @@ &pcie6a_phy {
 	status = "okay";
 };
 
+&pmc8380_3_gpios {
+	edp_bl_en: edp-bl-en-state {
+		pins = "gpio4";
+		function = "normal";
+		power-source = <1>; /* 1.8V */
+		input-disable;
+		output-enable;
+	};
+};
+
 &qupv3_0 {
 	status = "okay";
 };

-- 
2.44.1

Re: [PATCH 4/5] arm64: dts: qcom: x1e80100-crd: Fix backlight

[Konrad Dybcio]

On 10.07.2024 7:05 PM, Stephan Gerhold wrote:
> The backlight does not work correctly with the current display panel
> configuration: It works after boot, but once the display gets disabled it
> is not possible to get it back on. It turns out that the ATNA45AF01 panel
> needs exactly the same non-standard power sequence as implemented by the
> panel-samsung-atna33xc20 driver for sc7180-trogdor-homestar.
> 
> Switch the panel in the DT to the new compatible and make two more changes
> to make it work correctly:
> 
>  1. Add the missing GPIO for the panel EL_ON3 line (EDP_BL_EN on CRD and
>     enable-gpios in the DT).
>  2. Drop the regulator-always-on for the panel regulator. The panel does
>     not seem to power off properly if the regulator stays on.
> 
> Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
> ---

[...]

> +		power-source = <1>; /* 1.8V */

Would be nice to get the #defines for this PMIC instead..

> +		input-disable;
> +		output-enable;

LGTM otherwise

Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>

Konrad

[PATCH 5/5] arm64: defconfig: Add CONFIG_DRM_PANEL_SAMSUNG_ATNA33XC20

[Stephan Gerhold]

This is needed for the display panel to work on the Qualcomm
sc7180-trogdor-homestar and x1e80100-crd.

Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
---
 arch/arm64/configs/defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 5c9fcf9ad395..9572c337ec29 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -889,6 +889,7 @@ CONFIG_DRM_PANEL_KHADAS_TS050=m
 CONFIG_DRM_PANEL_MANTIX_MLAF057WE51=m
 CONFIG_DRM_PANEL_NOVATEK_NT36672E=m
 CONFIG_DRM_PANEL_RAYDIUM_RM67191=m
+CONFIG_DRM_PANEL_SAMSUNG_ATNA33XC20=m
 CONFIG_DRM_PANEL_SITRONIX_ST7703=m
 CONFIG_DRM_PANEL_TRULY_NT35597_WQXGA=m
 CONFIG_DRM_PANEL_VISIONOX_VTDR6130=m

-- 
2.44.1