Re: Commit d6e25b3590 breaks external video (HDMI) on mt8173 (chromebook oak)
Chun-Kuang Hu <[email protected]> Thu, 14 Aug 2025 22:38:48 +0800
| Newsgroups | dev.linux.lists.bugs,org.freedesktop.lists.dri-devel,org.infradead.lists.linux-mediatek |
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| Message-ID | <CAAOTY_8L_tJwL77wqBVxrmoMLEGgXue8wW5dz8TLfUg4Ehn4dw@mail.gmail.com> |
Forward to dri-devel and linux-mediatek. Andy Chernyak <[email protected]> =E6=96=BC 2025=E5=B9=B47=E6=9C=882= =E6=97=A5 =E9=80=B1=E4=B8=89 =E4=B8=8B=E5=8D=8811:12=E5=AF=AB=E9=81=93=EF= =BC=9A > > Kernel 6.16 has external video (both hdmi and displayport-over-usbc) brok= en (black screen) on mt8173-based chromebooks (platform codename "oak", dev= ice codename "hana"). Bisect points finger to following commit: > > From d6e25b3590a0679bca1a1becc04e3999f1dfd461 > From: Guillaume Ranquet <[email protected]> > Date: Tue, 15 Apr 2025 12:43:05 +0200 > Subject: drm/mediatek: hdmi: Use regmap instead of iomem for main registe= rs > In preparation for the addition of a new version of the HDMI IP > which will need to share its iospace between multiple subdrivers, > and in preparation for moving out the common bits between the two, > migrate this driver to fully use regmap. > > Reverting d6e25b3590 with "patch -R" on top of 6.16-rc4 fixes this.