Re: [PATCH 2/2] drm/panel-simple: Add Innolux G156HCE-L01 panel entry

[Luca Ceresoli <luca.ceresoli@bootlin.com>]

Hi Marek,

On Mon, 31 Jul 2023 23:02:58 +0200
Marek Vasut <marex@denx.de> wrote:

> Add support for Innolux G156HCE-L01 15.6" 1920x1080 24bpp
> dual-link LVDS TFT panel. Documentation is available at [1].

Interesting, I'm bringing up this exact panel right now and found your
patch.

> The middle frequency is tuned slightly upward from 70.93 MHz
> to 72 MHz, otherwise the panel shows slight flicker.

Using 70.93 MHz here does not show any flickering. I even tried going
in the opposite direction and set 70 MHz, and to use different
backlight settings, all without any flickering.

Do you think you might be using a defective device? Would you have a
chance of testing another sample?

> diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
> index 396a22177c674..417dd69054fc1 100644
> --- a/drivers/gpu/drm/panel/panel-simple.c
> +++ b/drivers/gpu/drm/panel/panel-simple.c
> @@ -2377,6 +2377,37 @@ static const struct panel_desc innolux_g121x1_l03 = {
>  	},
>  };
>  
> +static const struct display_timing innolux_g156hce_l01_timings = {
> +	.pixelclock = { 120000000, 144000000, 150000000 },

In case the 144 MHz clock is kept, I'd add a comment here to clarify
the reason for diverging from the datasheet without the need for git
log.

Luca

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