On Thu, Jul 06, 2017 at 02:20:04AM +0300, Dmitry Osipenko wrote: > On 06.07.2017 01:54, Stephen Warren wrote: > > On 07/05/2017 04:13 PM, Dmitry Osipenko wrote: > >> On 05.07.2017 23:31, Stephen Warren wrote: > >>> On 07/05/2017 11:19 AM, Dmitry Osipenko wrote: > >>>> Some time ago Thierry Reding sent out patches that enabled UDC on NVIDIA > >>>> Tegra, unfortunately they haven't got enough traction to get into the > >>>> kernel. I've rebased those patches and added a fix for the Ethernet USB > >>>> Gadget on Tegra20, Marc Dietrich tested UDC driver on AC100 and Nicolas > >>>> Chauvet on TK1. Like an original patchset, this series adds support for > >>>> the peripheral mode only. > >>> > >>> Does this mean that the relevant ports no longer support host mode? That's going > >>> to be a user-visible regression, which doesn't sound like a good idea. Isn't OTG > >>> possible instead? > >> > >> We are going to switch only AC100 and TrimSlice to use the UDC driver. > > > > Really? I saw patches in the series for Beaver, Dalmore, and Jetson TK1 too. > > > > Yes, the "PHY" and "EHCI" nodes are disabled on those boards in DT. > > >> Do you > >> know whether that port is working in a host mode with the tegra-ehci driver on > >> these devices? > > > > If any USB port is enabled in the DT, it was certainly validated at some point. > > IIRC, we only have host mode enabled at present. So, yes, I'd expect this port > > to work in host mode currently without any issue. > > > > Okay, so we have to decide whether it's reasonable to switch AC100 and TrimSlice > to the peripheral mode. I think realistically chances that someone uses that > port in a host mode are quite low, while it works fine and probably more useful > in a device mode. Judging by this: http://trimslice.com/download/documentation/trim-slice-man.pdf at least TrimSlice doesn't seem to implement OTG, so we'd have to make a choice to support either host or peripheral mode. I guess technically it would need to be peripheral mode because pin 4 is not connected. Does a similar document exist for AC100? Thierry
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