[PATCH] drm/panel: simple: Fix Innolux G156HCE-L01 LVDS clock

[PATCH] drm/panel: simple: Fix Innolux G156HCE-L01 LVDS clock

[Luca Ceresoli]

This panel has been implemented in commit 225213f24c79 ("drm/panel-simple:
Add Innolux G156HCE-L01 panel entry") with a higher clock than the typical
one mentioned on the documentation to avoid flickering on the unit
tested. Testing on a different unit shows that the panel actually works
with the intended 70.93 MHz clock and even lower frequencies so the
flickering is likely caused either by a defective unit or by other
different components such as the bridge.

Fixes: 225213f24c79 ("drm/panel-simple: Add Innolux G156HCE-L01 panel entry")
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
---
 drivers/gpu/drm/panel/panel-simple.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index 56854f78441e..ec3a73bbfe30 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -2379,7 +2379,7 @@ static const struct panel_desc innolux_g121x1_l03 = {
 };
 
 static const struct display_timing innolux_g156hce_l01_timings = {
-	.pixelclock = { 120000000, 144000000, 150000000 },
+	.pixelclock = { 120000000, 141860000, 150000000 },
 	.hactive = { 1920, 1920, 1920 },
 	.hfront_porch = { 80, 90, 100 },
 	.hback_porch = { 80, 90, 100 },
-- 
2.34.1

Re: [PATCH] drm/panel: simple: Fix Innolux G156HCE-L01 LVDS clock

[Marek Vasut]

On 8/4/23 17:10, Luca Ceresoli wrote:
> This panel has been implemented in commit 225213f24c79 ("drm/panel-simple:
> Add Innolux G156HCE-L01 panel entry") with a higher clock than the typical
> one mentioned on the documentation to avoid flickering on the unit
> tested. Testing on a different unit shows that the panel actually works
> with the intended 70.93 MHz clock and even lower frequencies so the
> flickering is likely caused either by a defective unit or by other
> different components such as the bridge.
> 
> Fixes: 225213f24c79 ("drm/panel-simple: Add Innolux G156HCE-L01 panel entry")
> Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
> ---
>   drivers/gpu/drm/panel/panel-simple.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
> index 56854f78441e..ec3a73bbfe30 100644
> --- a/drivers/gpu/drm/panel/panel-simple.c
> +++ b/drivers/gpu/drm/panel/panel-simple.c
> @@ -2379,7 +2379,7 @@ static const struct panel_desc innolux_g121x1_l03 = {
>   };
>   
>   static const struct display_timing innolux_g156hce_l01_timings = {
> -	.pixelclock = { 120000000, 144000000, 150000000 },
> +	.pixelclock = { 120000000, 141860000, 150000000 },
>   	.hactive = { 1920, 1920, 1920 },
>   	.hfront_porch = { 80, 90, 100 },
>   	.hback_porch = { 80, 90, 100 },

Odd, now I don't see the flicker anymore.

Tested-by: Marek Vasut <marex@denx.de> # MX8MM with LT9211
Reviewed-by: Marek Vasut <marex@denx.de>

Thanks !

Re: [PATCH] drm/panel: simple: Fix Innolux G156HCE-L01 LVDS clock

[Neil Armstrong]

On 04/08/2023 17:10, Luca Ceresoli wrote:
> This panel has been implemented in commit 225213f24c79 ("drm/panel-simple:
> Add Innolux G156HCE-L01 panel entry") with a higher clock than the typical
> one mentioned on the documentation to avoid flickering on the unit
> tested. Testing on a different unit shows that the panel actually works
> with the intended 70.93 MHz clock and even lower frequencies so the
> flickering is likely caused either by a defective unit or by other
> different components such as the bridge.
> 
> Fixes: 225213f24c79 ("drm/panel-simple: Add Innolux G156HCE-L01 panel entry")

This is the wrong sha, it should be eae7488814b5

Neil

> Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
> ---
>   drivers/gpu/drm/panel/panel-simple.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
> index 56854f78441e..ec3a73bbfe30 100644
> --- a/drivers/gpu/drm/panel/panel-simple.c
> +++ b/drivers/gpu/drm/panel/panel-simple.c
> @@ -2379,7 +2379,7 @@ static const struct panel_desc innolux_g121x1_l03 = {
>   };
>   
>   static const struct display_timing innolux_g156hce_l01_timings = {
> -	.pixelclock = { 120000000, 144000000, 150000000 },
> +	.pixelclock = { 120000000, 141860000, 150000000 },
>   	.hactive = { 1920, 1920, 1920 },
>   	.hfront_porch = { 80, 90, 100 },
>   	.hback_porch = { 80, 90, 100 },

Re: [PATCH] drm/panel: simple: Fix Innolux G156HCE-L01 LVDS clock

[Luca Ceresoli]

Hello Neil,

On Mon, 14 Aug 2023 14:38:51 +0200
Neil Armstrong <neil.armstrong@linaro.org> wrote:

> On 04/08/2023 17:10, Luca Ceresoli wrote:
> > This panel has been implemented in commit 225213f24c79 ("drm/panel-simple:
> > Add Innolux G156HCE-L01 panel entry") with a higher clock than the typical
> > one mentioned on the documentation to avoid flickering on the unit
> > tested. Testing on a different unit shows that the panel actually works
> > with the intended 70.93 MHz clock and even lower frequencies so the
> > flickering is likely caused either by a defective unit or by other
> > different components such as the bridge.
> > 
> > Fixes: 225213f24c79 ("drm/panel-simple: Add Innolux G156HCE-L01 panel entry")  
> 
> This is the wrong sha, it should be eae7488814b5

Ah, good catch, Thank you!

v2 on its way.

Luca

-- 
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com