Re: [PATCH] drm/mediatek: mtk_dsi: enable hs clock during pre-enable
From: Adam Thiede
Date: Mon Jul 27 2026 - 08:55:30 EST
On 7/27/26 07:48, Gary Bisson wrote:
Hi Thorsten,I'm also happy to try out any patches and report back, too! Just point me to it and let me know which release/RC I should apply it to.
On Mon, Jul 27, 2026 at 02:28:56PM +0200, Thorsten Leemhuis wrote:
[top-posting to facilitate]
Gary, Angelo, what's the status here? It looks like this fell through
the cracks -- or was this issue fixed in between somehow? If yes: great!
If not: Would be good to finally resolve this, as we are long past "fix
within a week" rule of thumb from Linus:
https://www.kernel.org/doc/html/latest/process/handling-regressions.html#on-how-quickly-regressions-should-be-fixed
Not much happened I'm afraid. The status as I see is:
- this patch is necessary to have TI SN65DSI83 working
- this patch also follows the DRM guidelines saying that HS clock must
be enabled during pre_enable (see previous answer / [1])
- this patch has been successfully tested against MIPI-DSI panels (by
Angelo) and LVDS panels via TI bridge (by myself)
- Adam reported an issue with another bridge (PS8640) where resume is
broken
- Esben offered a patch to the TI bridge that would fix the issue we
were seeing in the first place.
But for the last two points, I'm not sure this calls for a revert yet:
- enabling HS clock in pre_enable still is what should be done [1]
- maybe the issue Adam is facing is due to the bridge driver instead as
it could not be reproduced with another setup
- Esben patch would break the SN65DSI83 init sequence, suggesting that
the culprit really is the MIPI bridge for not following the HS clock
requirement in pre_enable instead [2]
So if we agree on the fact that HS clock must be set during pre_enable
then I don't see a reason to revert that commit.
Regards,
Gary
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpu/drm/drm_bridge.c#n169
[2] https://patchwork.kernel.org/project/dri-devel/patch/20260711-ti-sn65dsi83-fixes-v1-2-d85eb5342b98@xxxxxxxxxx/