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Message-ID: <5f2f22f5-340b-fdf7-585d-3665a0e8a087@denx.de>
Date:   Sat, 5 Aug 2023 18:46:18 +0200
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Subject: Re: [PATCH] drm/panel: simple: Fix Innolux G156HCE-L01 LVDS clock
Content-Language: en-US
To:     Luca Ceresoli <luca.ceresoli@bootlin.com>,
        dri-devel@lists.freedesktop.org
Cc:     Neil Armstrong <neil.armstrong@linaro.org>,
        Sam Ravnborg <sam@ravnborg.org>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>, linux-kernel@vger.kernel.org,
        Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
        Paul Kocialkowski <paul.kocialkowski@bootlin.com>
References: <20230804151010.834990-1-luca.ceresoli@bootlin.com>
From:   Marek Vasut <marex@denx.de>
In-Reply-To: <20230804151010.834990-1-luca.ceresoli@bootlin.com>
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Precedence: bulk

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 !