This is unfortunately handled by the Type C controller firmware and not controllable from Linux. It's the same reason why anything Thundebolt doesn't work instead of falling back to USB mode.
True type C cables are always DP compatible if they're USB3 compatible, so as you've found out the only standard fix is to go through a Type A adapter. It would be technically possible to build a type C cables that does the same thing, but then it would be directional (and not standards compliant)!
Asahi Linux /
npub15z…3t7sv
2024-08-12 10:31:37
in reply to nevent1q…37ga
Author Public Key
npub15zxvdefgmppkljpvr6m8cu7pgkv76c7a2dxxlph0z738qx2lq6hql3t7svPublished at
2024-08-12 10:31:37Event JSON
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"content": "This is unfortunately handled by the Type C controller firmware and not controllable from Linux. It's the same reason why anything Thundebolt doesn't work instead of falling back to USB mode.\n\nTrue type C cables are always DP compatible if they're USB3 compatible, so as you've found out the only standard fix is to go through a Type A adapter. It would be technically possible to build a type C cables that does the same thing, but then it would be directional (and not standards compliant)!",
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