Re: [PATCH v4 2/9] drm/mediatek: dsi: Fix DSI RGB666 formats and definitions

From: Alexandre Mergnat
Date: Tue Feb 06 2024 - 10:03:35 EST


Reviewed-by: Alexandre Mergnat <amergnat@xxxxxxxxxxxx>

On 06/02/2024 13:07, AngeloGioacchino Del Regno wrote:
The register bits definitions for RGB666 formats are wrong in multiple
ways: first, in the DSI_PS_SEL bits region, the Packed 18-bits RGB666
format is selected with bit 1, while the Loosely Packed one is bit 2,
and second - the definition name "LOOSELY_PS_18BIT_RGB666" is wrong
because the loosely packed format is 24 bits instead!

Either way, functions mtk_dsi_ps_control_vact() and mtk_dsi_ps_control()
do not even agree on the DSI_PS_SEL bit to set in DSI_PSCTRL: one sets
loosely packed (24) on RGB666, the other sets packed (18), and the other
way around for RGB666_PACKED.

Fixing this entire stack of issues is done in one go:
- Use the correct bit for the Loosely Packed RGB666 definition
- Rename LOOSELY_PS_18BIT_RGB666 to LOOSELY_PS_24BIT_RGB666
- Change ps_bpp_mode in mtk_dsi_ps_control_vact() to set:
- Loosely Packed, 24-bits for MIPI_DSI_FMT_RGB666
- Packed, 18-bits for MIPI_DSI_FMT_RGB666_PACKED

--
Regards,
Alexandre