@purism Glimpse of a driving an external screen via usb-c's -alt-mode:

@purism And here's the connected to a usb-c hub that has a keyboard/mouse connected via usb and driving the external screen via dp-alt-mode. Needs some hacks still but we're getting there:

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@purism …and here's a quick Quake II demo using the docked via usb-c (audio is from L5's built in speaker) - might be a bit more exciting than running (which also works):

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@agx @purism cool! is it LCDIF on the internal output and DCSS on the DP?

@mntmn @purism yes, external uses i.MX8MQ's DCSS so we can use all it's goodies, internal is / LCDIF

@agx @purism nice! you’re not using PCIe in parallel right? would be interesting for me if LCDIF is stable with that

@agx @purism looks promising! Can't wait for evergreen 😀

Awesome to see DisplayPort Alt Mode mode working and in 3D!

I noticed that the i.MX 8M Quad documentation shows a DRM blob for using HDMI, so I was wondering if you found a way around that using DCSS or will we be limiited to DisplayPort Alt Mode?

@amosbatto DisplayPort alt-mode is in fact how most USB-C to HDMI adapters work. HDMI alt-mode, although it exists, is rather rare and not supported that well across various hardware.

@dos, OK, that makes sense, but if DisplayPort Alt Mode is carrying an HDMI signal, we still have the same question for RYF certification.

Does the DCSS driver for the iMX8MQ no longer require the HDMI DRM blob or is the video being converted to HDMI outside the iMX8MQ?

@amosbatto DisplayPort alt-mode is carrying a DisplayPort signal, not HDMI. It's usually the adapter that converts it to HDMI.

@dos, Oh I assumed that DP alt-mode was like normal DP, but I Googled it and found that there is no DP Dual Mode (DP++) over DP alt-mode, so it isn't possible to send an HDMI signal over DP alt-mode. We will need an active adapter to convert from DP to HDMI.
This article explains it:

@amosbatto Yes, I know, and I said that earlier - most USB-C to HDMI adapters use DP alt-mode, which is universally supported, and not HDMI alt-mode, which is rather rare and can't be used together with USB signal at the same time.

@dos, HDMI alt-mode not being common gives me hope for the future. As more devices move to USB-C, we can get rid of HDMI, which requires licensing fees, and just use DisplayPort, which is a freer standard. Nice to find something positive in this dreary world.

@agx @purism Phosh in desktop mode supports tiling already?!

@kyle @purism It tiles left/right via keyboard shortcuts, the rest is yet to come.

@agx @purism So the USB hub can output video, input keyboard and mouse. But can it also charge (or at least power) the phone ?

@lord @purism The blue cable on the picture goes into the wall wart and if that supplies enough power (and wall wart, hub and phone agree on USB PD contracts) it'll also charge the phone. That's one of the tricky parts we're currenlty working on.

@agx @purism very impressive :) can't to have a phone that's usable as a desktop!

@agx @purism Nice! Next time can we a get a bit more playtime? 😆

@Phaserune @purism I need somebody holding the camera, then i can operate keybod and mouse.

@agx @purism

I have a feeling I'm not that far away, and I'd be happy to help!

@agx @purism killing it, looks like literally and figuratively. The Librem 5 running PureOS (running phosh) as a desktop is going to blow peoples minds...

@agx @purism , That's awesome!

Do you have any idea what will be the max resolution supported by DisplayPort alt-mode on the Librem 5? That question came up on the Purism forum last year.

@amosbatto @purism with an adapter that can use all 4 DP lane pairs we should be able to get up to 4k@60Hz , the 'regular' hubs only uses 2 lane pairs (4k@30Hz) - but my screens have way lower resoluiton so that's not tested yet.

@agx @purism, I checked the i.MX 8M Quad data sheet and it says that it only supports DisplayPort 1.3 with a max resolution of 4K at 30fps. Still nice to know that 4K is theoretically possible. I was only expecting 1080p video, so I will be happy if we can get anything higher than that.

@amosbatto @purism my data sheet says @60Hz so looking forward to try that on a suitable screen.

@agx @purism viewing this on librem social iPhone SE crashes the app, not sure how to extract logs

@agx @purism Since we are taking PureOS; a full-blown desktop OS; and putting it on the Librem 5 phone, we have turned the entire market on its head. Android and iOS have been trying (and failing) to make their mobile OS a productivity desktop OS. This is very exciting to show the future already functioning.

@agx @purism will any usb-c hub work or do I have to take something into account?

@pamaca @purism it needs to do dp-alt-mode over usb-c. I expect there to be a recommended list of hubs/adapters at some point since there's lots of variance (number of supported lane pairs, usb 3.0 or not, ...) - it also depends on the screen you want to connect.

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