[mythtv-users] Hauppauge HD-PVR trials and tribulations.

[Andrew C. (AFPup) Stadt]

On 14-12-20 11:14 PM, Stephen Worthington wrote:
> <snip>
> I guess that it depends on what USB 3 chip your motherboard has,
> because I have never had any problems with Mythbuntu on my Asus
> M5A97Evo motherboard.  I have been running two hard drives on a dual
> external USB 3 drive mount, and occasionally using a USB 3 stick.  I
> have not tried USB 2 devices on the USB 3 ports.  And similarly on my
> MSI GT70 laptop with Mythbuntu - the only problem I had there was that
> my USB 2 DVB-T tuners did not work on my USB 3 ports in Mythbuntu
> 12.04 the first time I tried them.  I have not tried again with more
> recent kernels.  USB 3 devices on the USB 3 ports work flawlessly.  I
> certainly have never had any problems on the USB 2 ports due to having
> USB 3 working.
>
> The USB 3 ports on the Asus M5A97Evo seem to be an Asmedia ASM1042
> chip, and on the GT70 they seem to be part of the main Intel chipset.
>
My board was a Gigabyte GA-Z87X-D3H, the built-in USB ports were (2x USB 
3/ 6x USB 2) are supplied by the X87 Express chipset and 8 additional 
ports (all USB  3) were supplied by a Renesas controller (currently 
disabled, so not sure the specific chip).  I guess due to the 
architecture of the system, the xhci driver would bind to all the ports 
in the system, even the USB 2 ones, and the HD-PVR driver seem(ed) to 
have some kind of buffer/timeout issue/bug with that driver.  My 
understanding at the time, from a chat I had with one of the xhci devs, 
was the xhci implements a new internal architecture and actually meets 
the specs, but in doing so reveals several flaws in current device 
drivers, unfortunately that dev wasn't able to give me any specifics on 
what to look for.

It is worth noting that a large number of bugs filed against the xhci 
driver turn out to be cable/power issues not the driver itself. I guess 
usb 2 was just so much more forgiving.