Rob, On Mon, Nov 2, 2015 at 8:12 AM, Rob Herring <robh+dt@xxxxxxxxxx> wrote: > On Fri, Oct 30, 2015 at 3:17 PM, Douglas Anderson <dianders@xxxxxxxxxxxx> wrote: >> From: Doug Anderson <dianders@xxxxxxxxxxxx> >> >> On the rk3288 USB host-only port (the one that's not the OTG-enabled >> port) the PHY can get into a bad state when a wakeup is asserted (not >> just a wakeup from full system suspend but also a wakeup from >> autosuspend). > > I would think re-enumerating means autosuspend is broken. Yes, it is broken on this port. I've been trying to figure out how to disable autosuspend at the driver level. Until then we can do it with udev rules but that's much less ideal. On our current system we have autosuispend turned off for most things via udev and laptop-mode-tools. ...so really the only case we see this reset happen is if an empty hub is plugged in and then you plug something into the hub. The reset isn't terrible and is much better than the device getting stuck. You can also see the reset doing its thing if you fully suspend the system and try to wake up from a keyboard or a mouse attached to the port. Being able to wake up (and then seeing a reset) is still better than not being able to wake up. >> We can get the PHY out of its bad state by asserting its "port reset", >> but unfortunately that seems to assert a reset onto the USB bus so it >> could confuse things if we don't actually deenumerate / reenumerate the >> device. >> >> We can also get the PHY out of its bad state by fully resetting it using >> the reset from the CRU (clock reset unit), which does a more full >> reset. The CRU-based reset appears to actually cause devices on the bus >> to be removed and reinserted, which fixes the problem (albeit in a hacky >> way). > > The reset from the CRU goes to the PHY, correct? Therefore, the > binding should reflect that. Connecting it to the host controller is a > hack. > > So describe the reset connection properly and then add a .phy_reset() > hook to the phy subsystem. Then call that when flag property you added > is set. As per previous email, I disagree. The fact that there may be more than one reset exposed from the PHY and that there is not a tightly coupled relationship between a PHY driver and a USB driver means that we would need to re-invent the reset API on top of the PHY API. In my case I am exposing a single reset at the moment, but there may be reasons to expose additional "PHY" resets in the future. http://www.gossamer-threads.com/lists/linux/kernel/2289780#2289780 ...using the existing reset API seems better. -- 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
