I think it's a bit more complicated with HDMI, but you can access i2c on GPUs just fine (it's used for DDC). I think I only tested this on Intel iGPUs so it's good to know it works on (at least older) AMD APUs as well.
In fact, Google did some cursed stuff in 2013 where they hooked up an input device (either touchscreen or touchpad, I don't remember) to iGPU's i2c bus (I think they did it in LINK)
elly
npub19w…8g8gs
2026-04-08 19:59:26 UTC
in reply to nevent1q…a5de
Author Public Key
npub19wj8tgf5p67elrkz0kgh8n28779aum6cwc838p2rqwaxh4hn4ycq28g8gsSeen on
wss://relay.momostr.pinkPublished at
2026-04-08 19:59:26 UTCEvent JSON
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