<html><body><p> <pre> On Fri, 2025-01-10 at 14:31 +0100, Alexandre Mergnat wrote: > External email : Please do not click links or open attachments until you have verified the sender or the content. > > > Currently, mtk_dsi_lane_ready (which setup the DSI lane) is triggered > before mtk_dsi_poweron. lanes_ready flag toggle to true during > mtk_dsi_lane_ready function, and the DSI module is set up during > mtk_dsi_poweron. > > Later, during panel driver init, mtk_dsi_lane_ready is triggered but does > nothing because lanes are considered ready. Unfortunately, when the panel > driver try to communicate, the DSI returns a timeout. > > The solution found here is to put lanes_ready flag to false after the DSI > module setup into mtk_dsi_poweron to init the DSI lanes after the power / > setup of the DSI module. I'm not clear about what happen. I think this DSI flow has worked for a long time. So only some panel has problem? And another question. Do you mean mtk_dsi_lane_ready() do some setting to hardware, but lane is not actually ready? Or mtk_dsi_lane_ready() configure the hardware and lane is is actually ready, but something make it not ready again, what's the thing which break lane ready? If this is a bug fix, add Fixes tag. Regards, CK > > Signed-off-by: Alexandre Mergnat <amergnat@baylibre.com> > --- > drivers/gpu/drm/mediatek/mtk_dsi.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c > index e61b9bc68e9a..dcf0d93881b5 100644 > --- a/drivers/gpu/drm/mediatek/mtk_dsi.c > +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c > @@ -724,6 +724,8 @@ static int mtk_dsi_poweron(struct mtk_dsi *dsi) > mtk_dsi_config_vdo_timing(dsi); > mtk_dsi_set_interrupt_enable(dsi); > > + dsi->lanes_ready = false; > + > return 0; > err_disable_engine_clk: > clk_disable_unprepare(dsi->engine_clk); > > -- > 2.25.1 > </pre> </p></body></html><pre>************* MEDIATEK Confidentiality Notice ******************** The information contained in this e-mail message (including any attachments) may be confidential, proprietary, privileged, or otherwise exempt from disclosure under applicable laws. It is intended to be conveyed only to the designated recipient(s). Any use, dissemination, distribution, printing, retaining or copying of this e-mail (including its attachments) by unintended recipient(s) is strictly prohibited and may be unlawful. If you are not an intended recipient of this e-mail, or believe that you have received this e-mail in error, please notify the sender immediately (by replying to this e-mail), delete any and all copies of this e-mail (including any attachments) from your system, and do not disclose the content of this e-mail to any other person. Thank you! </pre>