Re: [PATCH] drm/mediatek: mtk_dsi: enable hs clock during pre-enable
Adam Thiede <[email protected]>
| Newsgroups | org.infradead.lists.linux-mediatek,dev.linux.lists.regressions,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
On 7/27/26 07:48, Gary Bisson wrote: > Hi Thorsten, > > 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/[email protected]/ 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.