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. >> That should be a micro USB port. Since that port is working in a >> device mode by default, I presume that switching it into a host mode would >> require some extra 'dance', otherwise I may drop the AC100 / TrimSlice patches. >> >> The full-featured OTG should be possible, it could be done later if desired. I'm >> leaving it to somebody else to implement. -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
