[PATCH v7,3/4] drm/mediatek: keep dsi as LP00 before dcs cmds transfer

[Rex-BC Chen]

On Fri, 2022-05-20 at 10:00 +0800, xinlei.lee at mediatek.com wrote:
> From: Jitao Shi <jitao.shi at mediatek.com>
> 
> To comply with the panel sequence, hold the mipi signal to LP00
> before the dcs cmds transmission,
> and pull the mipi signal high from LP00 to LP11 until the start of
> the dcs cmds transmission.
> The normal panel timing is :
> (1) pp1800 DC pull up
> (2) avdd & avee AC pull high
> (3) lcm_reset pull high -> pull low -> pull high
> (4) Pull MIPI signal high (LP11) -> initial code -> send video
> data(HS mode)
> The power-off sequence is reversed.
> If dsi is not in cmd mode, then dsi will pull the mipi signal high in
> the mtk_output_dsi_enable function.
> The delay in lane_ready func is the reaction time of dsi_rx after
> pulling up the mipi signal.
> 
> Fixes: 2dd8075d2185 ("drm/mediatek: mtk_dsi: Use the drm_panel_bridge
> API")
> 
> Cc: <stable at vger.kernel.org> # 5.10.x: b255d51e3967: sched: Modify
> dsi funcs to atomic operations
> Cc: <stable at vger.kernel.org> # 5.10.x: 72c69c977502: sched: Separate
> poweron/poweroff from enable/disable and define new funcs
> Cc: <stable at vger.kernel.org> # 5.10.x
> Signed-off-by: Jitao Shi <jitao.shi at mediatek.com>
> Signed-off-by: Xinlei Lee <xinlei.lee at mediatek.com>
> Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno at collabora.com>
> ---

Reviewed-by: Rex-BC Chen <rex-bc.chen at mediatek.com>