On 24 March 2018 at 08:08, Giles Orr via talk <[email protected]> wrote: > On 23 March 2018 at 20:01, Scott Sullivan via talk <[email protected]> wrote: >> >> On 2018-03-23 12:50 PM, Giles Orr via talk wrote: >>> >>> A couple days ago I got a Best Buy flyer, and they have this item: >>> >>> >>> https://www.bestbuy.ca/en-ca/product/asus-zenscreen-15-6-fhd-60hz-5ms-gtg-ips-lcd-monitor-mb16ac-dark-grey/10737845.aspx >>> <https://www.bestbuy.ca/en-ca/product/asus-zenscreen-15-6-fhd-60hz-5ms-gtg-ips-lcd-monitor-mb16ac-dark-grey/10737845.aspx>? >>> >>> It's a portable IPS LCD screen from Asus. I have a similar item from >>> about three years ago that has two connectors, one for USB power-only and >>> the other for VGA/HDMI. There were other models at the time that used only >>> one connector, USB for both data and power - but that required a driver (and >>> would have been painfully slow if it was USB2). >>> >>> But now here's this new model: it's one connector only, USB-C. And >>> presumably USB3.1. And USB3.1 can carry video. But at this point I get >>> lost among the standards and their implementations and which one supports >>> what. I have an Asus Zenbook (it's Linux-only at this point) that has a >>> USB-C connector, but I suspect it's USB3.0. So the first question is: how >>> do I check that? Second, does Linux support video-over-USB3.1? Do I need a >>> special cable? Is this "Thunderbolt?" How can I check if my machine would >>> support this? >> >> >> The Spec you linked say it's DisplayLink, which is the software based >> video solution that requires a driver. >> >> https://en.wikipedia.org/wiki/DisplayLink >> >> USB-C is only a specification for a cable and connector, and somewhat >> agnostic about the data communications spec used across it. The cables are >> of high enough quality that they can support multiple data communications >> specs, generally referred to as alt-modes. >> >> https://en.wikipedia.org/wiki/USB-C#Alternate_Mode_partner_specifications >> >> Thunderbolt 3 for example co-oped the USB-C cable spec for it's cables, >> much like in the previous generations it co-oped the mini-displayport cable >> spec. >> >> Intel makes a point that a port carrying Thunderbolt 3 should also be >> cross wired with USB 3.X and Display Port hardware to output those signals >> as well. >> >> So if you want a monitor that uses a Type-C connector, your looking for a >> display-port monitor. Which your not likely to find in the portable market >> yet. >> > > Now that I knew what to look for, re-examination of the text and pictures > shows a couple interesting things: "USB Type-C connectivity with hybrid > signal solution for Type-C and Type-A source compatibility (requires a > DisplayLink driver for Type-A connection)." So it's implying that it > doesn't need a driver for Type-C. And looking at the pictures, there's a > "DisplayPort" icon next to one of the buttons on the front. So ... > > My other questions stand: > > - how can I figure out what USB protocol (3.0 or 3.1) the type-C connector > on my Linux computer supports?
lspci -d ::0c03 -k will display the vendors controller and kernel driver in use. > - (clearer understanding leads to a clearer question here, although I'm > still not sure I'm saying it right) does Linux support DisplayPort video > over USB-C? I think the short answer is yes. If you can hard wire a DisplayPort to HDMI adapter cable you must surely be able to sink to the host connections logically as well. Has somebody done this yet, I don't know. Since kernel 4.12 there has been development on a state machine for hosting sinks. https://www.phoronix.com/scan.php?page=news_item&px=USB-Type-C-Promotion-Linux-4.15 Power management and signalling are all represented, soft-jacking is another issue. https://superuser.com/questions/1192638/whats-up-with-hdmi-and-displayport-over-usb-c *Alternate mode data* https://github.com/torvalds/linux/blob/master/drivers/usb/typec/tcpm.c HTH > > -- > Giles > https://www.gilesorr.com/ > [email protected] > > --- > Talk Mailing List > [email protected] > https://gtalug.org/mailman/listinfo/talk > --- Talk Mailing List [email protected] https://gtalug.org/mailman/listinfo/talk
