[L] Change in coreboot[main]: soc/mediatek: Add common implementation to configure display

[Yidi Lin (Code Review)]

Attention is currently required from: Hung-Te Lin, Paul Menzel, Yu-Ping Wu.

Yidi Lin has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/79776?usp=email )

Change subject: soc/mediatek: Add common implementation to configure display
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Patch Set 4:

(5 comments)

File src/mainboard/google/geralt/panel.c:

https://review.coreboot.org/c/coreboot/+/79776/comment/7727dc31_6d8e6066 :
PS3, Line 27: if (!panel || panel->disp_path == DISP_PATH_NONE) {
            : 		printk(BIOS_ERR, "%s: Panel %u is not supported.\n", __func__, active_panel_id);
            : 		return NULL;
            : 	}
> I think the check can also be moved to `mtk_display_init()`.

Done

File src/soc/mediatek/common/display.c:

https://review.coreboot.org/c/coreboot/+/79776/comment/f7e26f3d_4d953413 :
PS3, Line 15: void
> Can we return the pointer `&buffer. […]

Done

https://review.coreboot.org/c/coreboot/+/79776/comment/70b07dec_eec2cb37 :
PS3, Line 88: (
> nit: No need for parentheses.

Done

File src/soc/mediatek/common/include/soc/display.h:

https://review.coreboot.org/c/coreboot/+/79776/comment/f324875d_9f270634 :
PS3, Line 20: struct
> const

Done

File src/soc/mediatek/mt8188/include/soc/ddp.h:

https://review.coreboot.org/c/coreboot/+/79776/comment/06687866_7caf202d :
PS3, Line 286: void mtk_ddp_init(void);
             : void mtk_ddp_mode_set(const struct edid *edid, enum disp_path_sel path);
> Since these 2 functions are called from common/display. […]

Done